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Ipoacusia e infezione congenita da citomegalovirus: i risultati di uno studio retrospettivo di 11 anni basato sui dati di laboratorio.Il citomegalovirus è la più comune causa di infezione congenita nei paesi industrializzati, con una prevalenza stimata intorno allo 0.3-2% dei nati vivi. Di questi, il 10-15% presenta sequele tardive tra cui deficit visivi, uditivi, ritardo mentale. La infezione congenita da citomegalovirus, ad oggi, è ancora ritenuta la principale causa di ipoacusia neurosensoriale infantile su base non genetica. Sebbene tale correlazione sia stata descritta più di 50 anni fa, la storia naturale del coinvolgimento dell’orecchio interno non è stata ancora completamente definita. La ipoacusia neurosensoriale è la sequela più frequente ed in una percentuale variabile, a seconda delle casistiche fino al 30%, la soglia è caratterizzata da fluttuazioni o deterioramento progressivo. Lo scopo di questo studio è stato quello di valutare la prevalenza della ipoacusia nei casi di infezione congenita da CMV della provincia di Modena, partendo dal data base del laboratorio di Microbiologia e Virologia, centro di riferimento per la intera provincia. Inoltre, ci si è proposti di valutare la entità della ipoacusia come sequela tardiva. Sono stati arruolati tutti i bambini sottoposti ad esame delle urine per sospetta infezione da CMV o mediante ricerca del DNA virale su Guthrie Card, nel periodo compreso tra gennaio 2004 e dicembre 2014. Mediante il contributo dei pediatri di famiglia e del servizio di Audiologia di Modena sono state accolte le informazioni cliniche sulla eventuale presenza alla nascita o insorgenza successiva di ipoacusia, escludendo dallo studio i casi in cui ciò non è stato possibile. I risultati hanno dimostrato una prevalenza annuale di infezione congenita da citomegalovirus stabile nel tempo nonostante l’aumento progressivo dei nati sottoposti al test. La prevalenza della ipoacusia nei casi di infezione congenita è in linea con la letteratura mentre non sono emersi, nel lungo periodo, casi con ipoacusia media/severa bilaterale ad insorgenza tardiva. La introduzione dello screening audiologico neonatale nella nostra regione (2012) ha permesso una diagnosi precoce della ipoacusia in quanto i nati con esito fail alle TEOAE venivano sottoposti anche al test per la ricerca del virus nelle urine. Pur con tutti i limiti di uno studio basato su revisione di casistica, possiamo concludere che permane la necessità di studi epidemiologici europei che consentano di definire meglio la relazione tra infezione congenita da CMV e patologia dell’orecchio interno in quanto l’impatto dei fattori ambientali e genetici non è ancora del tutto chiarito. La sinergia tra screening audiologico neonatale ed esecuzione del test per la ricerca del virus nelle urine si è dimostrata molto proficua.Congenital cytomegalovirus infection is considered the main cause of infantile non-genetic neurosensory hearing loss. Although this correlation was described more than 50 years ago, the natural history of internal ear involvement has not yet been fully defined. Hearing loss is the most frequent sequela and is seen in a variable percentage up to 30%; the hearing threshold is characterised by fluctuations or progressive deterioration. The purpose of this study was to evaluate the prevalence of hearing loss in cases of congenital CMV infection from Modena county, starting from the database of the microbiology and virology reference laboratory. All children undergoing urine testing for suspected CMV infection or viral DNA testing on Guthrie Card in the period between January 2004 and December 2014 were enrolled in the study. Family paediatricians were contacted and asked about clinical information on the possible presence at birth or subsequent occurrence of hearing loss, excluding cases where this was not possible. The results showed an annual prevalence of congenital cytomegalovirus infection among suspected cases that was stable over time despite the progressive increase in subjects tested. The prevalence of hearing loss was in line with the literature, whereas in long-term follow-up cases of moderate, medium-to-severe hearing loss with late onset were not detected. The introduction of newborn hearing screening in the county has allowed early diagnosis of hearing loss at birth as non-TEOAE-born births underwent a urine virus test. Moreover, despite all the limitations of the study, we can conclude that European epidemiological studies are needed to better define the relationship between congenital CMV infection and internal ear disease as the impact of environmental and genetic factors is still not entirely clarified.

The ICARUS T600 liquid argon (LAr) time projection chamber (TPC) underwent a major overhaul at CERN in 2016–2017 to prepare for the operation at FNAL in the Short Baseline Neutrino (SBN) program. This included a major upgrade of the photo-multiplier system and of the TPC wire read-out electronics. The full TPC wire read-out electronics together with the new wire biasing and interconnection scheme are described. The design of a new signal feed-through flange is also a fundamental piece of this overhaul whose major feature is the integration of all electronics components onto the signal flange. Initial functionality tests of the full TPC electronics chain installed in the T600 detector at FNAL are also described. The ICARUS T600 liquid argon (LAr) time projection chamber (TPC) underwent a major overhaul at CERN in 2016-2017 to prepare for the operation at FNAL in the Short Baseline Neutrino (SBN) program. This included a major upgrade of the photo-multiplier system and of the TPC wire read-out electronics. The full TPC wire read-out electronics together with the new wire biasing and interconnection scheme are described. The design of a new signal feed-through flange is also a fundamental piece of this overhaul whose major feature is the integration of all electronics components onto the signal flange. Initial functionality tests of the full TPC electronics chain installed in the T600 detector at FNAL are also described.

The EXPADES (EXotic PArticle DEtection System) detector array consists of 16 Double Side Silicon Strip Detectors (DSSSD) with active areas of 64 × 64 mm 2 , arranged in 8 ΔE (40/50 μm)–E (300 μm) telescopes. All detector faces are segmented into 32 × 2-mm wide strips, ensuring a 2 × 2 mm 2 pixel configuration. Eight ionization chambers can be alternatively used as ΔE stages or, if needed, as an additional third layer for more complex triple telescopes. The signals from silicon ΔE layers and from ionization chambers are read by standard electronics, while innovative 32-channel ASIC chips are employed for the readout of the E stages. The results of off-line tests with alpha sources and from the first in-beam experiment with a 17 O beam are presented.

Background and purpose: Sporadic amyotrophic lateral sclerosis (sALS) is a disease with a focal clinical onset and contiguous spread. We examined patterns of disease spread following symptoms onset in sALS and whether the pattern of spread predicted survival. Methods: Review of medical records (2003–2009) at London Ontario and Buenos Aires clinic cohorts retrieved 318 patients with sporadic sALS. According to patient self-report, we determined eight spread patterns: rostro-caudal, caudo-rostral, crossed, circular, superior interposed, middle interposed, inferior interposed and isolated. The variables studied were as follows: age, gender, sALS phenotypes, time from onset to diagnosis and time and direction of the spreading to the first region. Survival from symptoms onset was analysed by Kaplan–Meier, Tarone-Ware and Cox proportional hazards methods. Results: The direction of first spread was horizontal in 33%, rostral to caudal in 32% and caudal to rostral in 21%, whereas spread to remote regions was observed in 14% of patients. Survival curves and 3- and 5-year survival rates favoured patients with an isolated and caudo-rostral pattern of spread compared to patients progressing to distant regions without involvement in the intervening region, or superior and inferior interposed patterns (Tarone-Ware P = 0.001, v 2 = 0.002 and v 2 = 0.006, respectively). Factors affecting survival were gender, time to diagnosis, flail arm phenotype and age at diagnosis. Conclusions: We have provided evidence that not all spread in ALS is contiguous and that the nature of symptom progression influences survival. Patients with sALS with interposed patterns had a worse prognosis, whereas patients with caudo-rostral pattern fared better than the rest.

Objective To evaluate the effects of methadone, administered alone or in combination with acepromazine or xylazine, on sedation and on physiologic values in dogs. Study design Randomized cross-over design. Animals Six adult healthy mixed-breed dogs weighing 13.5 ± 4.9 kg. Methods Dogs were injected intramuscularly with physiologic saline (Control), or methadone (0.5mg kg−1) or acepromazine (0.1 mg kg−1) or xylazine (1.0 mg kg−1), or acepromazine (0.05 mg kg−1) plus methadone (0.5 mg kg−1) or xylazine (0.5 mg kg−1) plus methadone (0.5 mg kg−1) in a randomized cross-over design, with at least 1-week intervals. Sedation, pulse rate, indirect systolic arterial pressure, respiratory rate (RR), body temperature and pedal withdrawal reflex were evaluated before and at 15-minute intervals for 90 minutes after treatment. Results Sedation was greater in dogs receiving xylazine alone, xylazine plus methadone and acepromazine plus methadone. Peak sedative effect occurred within 30 minutes of treatment administration. Pulse rate was lower in dogs that received xylazine either alone or with methadone during most of the study. Systolic arterial pressure decreased only in dogs receiving acepromazine alone. When methadone was administered alone, RR was higher than in other treatments during most of the study and a high prevalence of panting was observed. In all treatments body temperature decreased, this effect being more pronounced in dogs receiving methadone alone or in combination with acepromazine. Pedal withdrawal reflex was absent in four dogs receiving methadone plus xylazine but not in any dog in the remaining treatments. Conclusions and clinical relevance Methadone alone produces mild sedation and a high prevalence of panting. Greater sedation was achieved when methadone was used in combination with acepromazine or xylazine. The combination xylazine–methadone appears to result in better analgesia than xylazine administered alone. Both combinations of methadone/sedative were considered effective for premedication in dogs.

We describe the experimental set-up of the Radioactive Ion Beam (RIB) in-flight facility EXOTIC consisting of: (a) two position-sensitive Parallel Plate Avalanche Counters (PPACs), dedicated to the event-by-event tracking of the produced RIBs and to time of flight measurements and (b) the new high-granularity compact telescope array EXPADES (EXotic PArticle DEtection System), designed for nuclear physics and nuclear astrophysics experiments employing low-energy light RIBs. EXPADES consists of eight Δ E – E res telescopes arranged in a cylindrical configuration around the target. Each telescope is made up of two Double Sided Silicon Strip Detectors (DSSSDs) with a thickness of 40/60 μm and 300 μm for the Δ E and Eres layer, respectively. Additionally, eight ionization chambers were constructed to be used as an alternative Δ E stage or, in conjunction with the entire DSSSD array, to build up more complex triple telescopes. New low-noise multi-channel charge-sensitive preamplifiers and spectroscopy amplifiers, associated with constant fraction discriminators, peak-and-hold and Time to Amplitude Converter circuits were developed for the electronic readout of the Δ E stage. Application Specific Integrated Circuit-based electronics was employed for the treatment of the Eres signals. An 8-channel, 12-bit multi-sampling 50 MHz Analog to Digital Converter, a Trigger Supervisor Board for handling the trigger signals of the whole experimental set-up and an ad hoc data acquisition system were also developed. The performance of the PPACs, EXPADES and of the associated electronics was obtained offline with standard α calibration sources and in-beam by measuring the scattering process for the systems 17O+58Ni and 17O+208Pb at incident energies around their respective Coulomb barriers and, successively, during the first experimental runs with the RIBs of the EXOTIC facility.

Distillation is a process of heating a substance until the most volatile constituents change into the vapor phase, and then cooling the vapors to recover the constituents in liquid form by condensation. The main purpose of distillation is to separate a mixture into individual components by taking advantage of their different level of volatilities. Distillation is one of the main methods of extracting essential oils from plants. The percentage of each constituent inCONTENTS7.1 Introduction 199 7.1.1 Steam Distillation 200 7.1.2 Simple Distillation and Fractional Distillation 201 7.1.3 Vacuum Fractional Distillation 2017.1.3.1 Signicant Reduction of Thermal Hazard 202 7.1.3.2 Greater Fractionation Efciency 202 7.1.3.3 Enhanced Purity of Distillate 2027.2 Industrial Scale Purication of Orange Peel Oil 203 7.2.1 Citrus Industry 203 7.2.2 Sweet Orange Oil 2037.2.2.1 Purication of Orange Peel Oil 203 7.2.2.2 Method of Deterpenation-VacuumFractional Distillation 204 7.2.2.3 Folded Oils 204 7.2.2.4 Uses and Applications 205 7.2.2.5 Experimental Results 2067.3 Conclusions 213 References 215the vapor phase usually depends on its vapor pressure at a certain temperature. The principle of vacuum distillation may be applied to substances such as oils that would be damaged by overheating by the conventional method (Ahmad, 2004). There are different methods of distillation, depending on the desired product; some of these processes are described below.

The Silicon Vertex Trigger (SVT) is a processor developed at CDF experiment to perform online fast and precise track reconstruction. SVT is made of two pipelined processors, the Associative Memory, finding low precision tracks, and the Track Fitter, refining the track quality whith high precision fits. We will describe the architecture and the performances of a next generation track fitter, the GigaFitter, developed to reduce the degradation of the SVT efficiency due to the increasing instantaneous luminosity. The GigaFitter reduces the track parameter reconstruction to a few clock cycles and can perform many fits in parallel, thus allowing high resolution tracking at very high rate. The core of the GigaFitter is implemented in a modern Xilinx Virtex-5 FPGA chip, rich in powerful DSP arrays. The FPGA is housed on a mezzanine board which receives the data from a subset of the tracking detector and transfers the fitted tracks to a Pulsar motherboard for the final corrections. Instead of the current 12 boards, one per sector of the detector, the final system will be much more compact, consisting of a single GigaFitter Pulsar board equipped with four mezzanine cards receiving the data from the entire tracking detector. Moreover, the GigaFitter modular structure is adequate to scale for much better performances and is general enough to be easily adapted to future High Energy Physics (HEP) experiments and applications outside HEP.

Sporadic amyotrophic lateral sclerosis (sALS) is a disease with a focal clinical onset and contiguous spread. We examined patterns of disease spread following symptoms onset in sALS and whether the pattern of spread predicted survival.Review of medical records (2003-2009) at London Ontario and Buenos Aires clinic cohorts retrieved 318 patients with sporadic sALS. According to patient self-report, we determined eight spread patterns: rostro-caudal, caudo-rostral, crossed, circular, superior interposed, middle interposed, inferior interposed and isolated. The variables studied were as follows: age, gender, sALS phenotypes, time from onset to diagnosis and time and direction of the spreading to the first region. Survival from symptoms onset was analysed by Kaplan-Meier, Tarone-Ware and Cox proportional hazards methods. The direction of first spread was horizontal in 33%, rostral to caudal in 32% and caudal to rostral in 21%, whereas spread to remote regions was observed in 14% of patients. Survival curves and 3- and 5-year survival rates favoured patients with an isolated and caudo-rostral pattern of spread compared to patients progressing to distant regions without involvement in the intervening region, or 'superior and inferior interposed patterns' (Tarone-Ware P = 0.001, χ(2) = 0.002 and χ(2) = 0.006, respectively). Factors affecting survival were gender, time to diagnosis, flail arm phenotype and age at diagnosis. We have provided evidence that not all spread in ALS is contiguous and that the nature of symptom progression influences survival. Patients with sALS with 'interposed patterns' had a worse prognosis, whereas patients with caudo-rostral pattern fared better than the rest.

Background/aims: We have previously shown that aquaporin-2 (AQP2) is down-regulated in the renal medulla of rats made hypertensive by chronic inhibition of nitric oxide synthase (NOS). It has been shown that AQP2 expression is regulated by the calcineurin/ nuclear factor of activated T cells (NFATc). Nitric oxide (NO) regulates the activity of NFATc via c-Jun-N-terminal kinase 2 (JNK2). Therefore, we hypothesized that increases in NO enhance NFATc-mediated up-regulation of AQP2 promoter activity. Methods: AQP2 mRNA and protein expression were detected in mouse renal papilla. AQP2-promoter-luciferase reporter and NFAT-luciferase reporter transfected MDCK cells were used to determine AQP2 promoter activity and NFATc activity, respectively. Cells were incubated with classic activators and inhibitors of NFATc and NO pathway. Results: Our results demonstrate that both Ca2+ and NO have a synergistic effect in increasing AQP2 mRNA and protein in mouse papilla, and in activating the AQP2 promoter in kidney-derived cells. In addition, NO enhances Ca2+-induced NFATc activation. The underlying mechanism involves increased NFATc nuclear import and decreased export via PKG-mediated inhibition of JNK1/2. Conclusions: This is the first study defining novel regulatory roles for NO and NFATc in the control of AQP2 expression, which is an important renal protein. Fil: Albertoni Borghese, Maria Florencia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Biología Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina Fil: Bettini, Layne M.. University Of New Mexico. School Of Medicine. Departament Of Cell Biology And Phisiology; Estados Unidos Fil: Nitta, Carlos H.. University Of New Mexico. School Of Medicine. Departament Of Cell Biology And Phisiology; Estados Unidos Fil: de Frutos, Sergio. University Of New Mexico. School Of Medicine. Departament Of Cell Biology And Phisiology; Estados Unidos Fil: Majowicz, Mónica. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Biología Celular y Molecular; Argentina Fil: González Bosc, Laura Veronica. University Of New Mexico. School Of Medicine. Departament Of Cell Biology And Phisiology; Estados Unidos

Real time event reconstruction plays a fundamental role in High Energy Physics experiments. The CDF experiment at the Tevatron collider performs a fast online reconstruction of high-resolution tracks using the Silicon Vertex Trigger (SVT). We will describe the architecture, the performance and the impact on CDF physics program of a next generation online track fitter, the GigaFitter, developed to improve the SVT track reconstruction efficiency as the Tevatron instantaneous luminosity increases. The core of the GigaFitter is implemented in a modern Xilinx Virtex-5 FPGA chip, rich in powerful DSP arrays. The higher computation power allows to perform many tasks in parallel, reducing the track parameter reconstruction to a few clock cycles: as a result, the GigaFitter can perform more than one fit per nanosecond. The Gigafitter installation and commissioning were successfully completed in February 2010: 12 Track Fitter boards, one per each azimuthal sector of the silicon detector, have been replaced by a single Gigafitter board receiving the data from the entire tracking detector. Besides being much more compact and robust than the previous system, the Gigafitter increases the SVT track reconstruction efficiency and acceptance and copes more effectively with the high-occupancy events that occur frequently at the high luminosities the Tevatron currently delivers. Moreover, its architecture is general enough to be adapted to different experimental environments: the experience gained with the Gigafitter upgrade will be essential for future SVT-like tracking processor such as FTK at Atlas experiment.

The Silicon-Vertex-Trigger (SVT) is a processor developed at CDF experiment to perform online fast and precise track reconstruction. SVT is made of two pipelined processors: the Associative Memory finds low precision tracks looking for coincidences between hits from the tracking detectors and track candidates (roads) stored in memory; the Track Fitter refines the track quality whith high precision fits. The GigaFitter is a next generation track fitter, developed to reduce the degradation of the SVT efficiency due to the increasing instantaneous luminosity. It reduces the track parameter reconstruction to a few clock cycles and can perform many fits in parallel, thus allowing high resolution tracking at very high rate. The core of the GigaFitter is implemented in a modern Xilinx Virtex-5 FPGA chip, rich of powerful DSP arrays. With respect to the current Track Fitter, the GigaFitter is faster and provided of much more memory to store a greater number of roads to be used in the fit; this results in an increased SVT efficiency as more track candidates can be reconstructed. The GigaFitter has been installed in parasitic mode at CDF and has been tested against the current Track Fitter. We will describe the GigaFitter architecture, the parasitic installation at CDF and the performances with respect to the current system.

Little research has focused on the communicative functions of intergenerational friendship. This exploratory study was guided by one major research question: Is there a difference between friendships within the same generation and friendships between individuals in different generations? Twenty elderly individuals and twenty undergraduate students were surveyed about their intergenerational friendships. The data were analyzed to determine similarities and differences between the two types of friendships. Implications and suggestions for future research are offered.

This 2×3 factorial design was employed to test the relationship between communication apprehension and cognitive learning. The results of this quasi‐experimental study indicate that highly apprehensive students scored higher on an objective (written) test than they scored on an equivalent oral test. Scores on the objective exam did not differ across levels of communication apprehension. In addition, a small negative correlation between communication apprehension and learning was observed in the oral testing condition. The expected curvilinear relationship between communication apprehension and learning under the oral testing condition was not observed. A negative linear relationship between communication apprehension and learning was observed.

The silicon-vertex-trigger (SVT) at CDF is made of two pipelined processors: the associative-memory, AM, finding low precision tracks (roads) and the track-fitter, TF, refining the track quality with high-precision fits. We describe a next generation track fitter, the GigaFitter, that performs more than a fit per nanosecond. This device is based on modern FPGA technology, rich of powerful DSP arrays, to reduce the track parameter reconstruction to few clock cycles and to perform many fits in parallel. The reduction to virtually zero of the time necessary for the fit is the goal to be achieved in order to maximize the computing power for high resolution tracking at very high rate. The GigaFitter will enhance the SVT capabilities during the high luminosity CDF final data taking and could be used in future experiments as well.

Aim: Neutrophil migration in the intestine depends on chemotaxis of neutrophils to CXC chemokines produced by epithelial cells. The goal of this project was to determine if acute induction of a CXC chemokine gradient originating from intestinal epithelial cells is sufficient to induce neutrophil influx into intact intestinal tissue. Methods and results: The authors developed a double transgenic mouse model with doxycycline induced human IL-8 expression restricted to intestinal epithelial cells. Doxycycline treatment of double transgenic mice for three days resulted in a 50-fold increase in the caecal IL-8 concentration and influx of neutrophils into the lamina propria. Although neutrophils entered the paracellular space between epithelial cells, complete transepithelial migration was not observed. Doxycycline treatment also increased the water content of the caecal and colonic stool, indicating dysfunctional water transport. However, the transmural electrical resistance was not decreased. Neutrophils recruited to the intestinal epithelium did not show evidence of degranulation and the epithelium remained intact as judged by histology. Conclusions: This conditional transgenic model of chemokine expression provides evidence that acute induction of IL-8 in the intestinal epithelium is sufficient to trigger neutrophil recruitment to the lamina propria, but additional activation signals are needed for full activation and degranulation of neutrophils, mucosal injury, and complete transepithelial migration.

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We discuss the method to classify raw material sports videos for broadcasting. Because the raw material sports videos sometimes do not edited, we cannot use the knowledge on edited videos. We use the color and edge features and evaluate whether we can classify the sports videos with those features. We also introduce “player” and “audience” class apart from each sport class to improve the classification results.

Strong scientific motivation are pushing the second generation of ground base Cherenkov telescopes to lower as much as possible their energy threshold. MAGIC will be the biggest single telescope, in terms of collection area (250 m 2 ), foreseen for the second-half of 2001. The large collection area, the newphotodetector and the electronic design will allow the telescope to lower the energy threshold below 30 GeV. For this telescope a two-level pattern trigger is designed to work in severe high pixel rate. The MAGIC trigger architecture and its implementation is presented. # 2001 Elsevier Science B.V. All rights reserved. PACS: 95.55.Ka

Mass gatherings are special situations for which mass medical care must be preplanned. Acute emergencies occur at public gatherings and medical coverage on site has proven benefit. Responsibility of general plan, management of specific problems, transport planning, communications system, guidelines and protocols, special situations management, ancillary supports, sources of extra help for unforeseen needs are the most important items to consider. In mass gatherings the whole emergency medical service (EMS) planning and management has to depend on the emergency department direction, with its authority on all aspects of patient care in the EMS system. This report concerns the planning of EMS and of medical care in a situation at risk for mass casualties at the Formula I Grand Prix-Championship Racing 'San Marino' of Imola.

Raman scattering and reststrahl measurements are presented on single crystals of the chalcopyrite CdSiP2, grown from the vapour phase by iodine transport. The spectra of the zone centered phonons from 60 to 520 cm−1 show a strong similarity to those of ZnSiP2. The mode distribution of the spectra can be completely interpreted by considering that the Γ-phonons of the chalcopyrites derive from the zincblende modes of the Γ, X, and W points. A qualitative comparison of the simpler modes in CdSiP2, to those in ZnSiP2, shows that the force constants do not deviate much from those of the corresponding binary and elemental semiconductors. Die Ergebnisse von Raman-Streuexperimenten und Reststrahlmessungen an CdSiP2,-Einkristallen mit Chalkopyritstruktur, hergestellt aus der Gasphase durch Jodtransport, werden dargelegt. Die Spektren der Γ-Phononen von 60 bis 520 cm−1 sind denen von ZnSiP2, sehr ahnlich. Die Verteilung der Moden in den Spektren ist vollig zu verstehen, wenn man berucksichtigt, das die Γ-Phononen in der Chalkopyritstruktur von den Moden am Γ-, X-und W-Punkt der Zinkblende hergeleitet werden konnen. Ein qualitativer Vergleich der einfachen Moden in CdSiP2, und ZnSiP2, zeigt, das die Kraftkonstanten nicht stark von denen der binaren Verbindungen oder Elementhalbleiter abweichen sollten.

The crystal quality of CdTe layers grown on single‐crystalline CdS by chemical vapor deposition is evaluated. Different x‐ray techniques have been applied to investigate the crystal perfection and defects. Good CdTe layers grow in the sphalerite phase with strong twinning about the [111] growth direction. No mixture of cubic and hexagonal phases, polytypes, stacking faults, and fiber texture are observed. Imperfect layers contain polycrystalline areas.

CdS/InP heterojunctions are grown by chemical vapor deposition of CdS on InP in an open‐tube H2S/H2 flow system. The importance of H2S admixture for the etching and cleaning of the InP surface is demonstrated. The solar cell has an open‐circuit voltage of 0.78 V, fill factor of 0.75, and a power conversion efficiency of 13.5% for AM2 conditions.

The spectra of the zone-centered phonons in five compounds of the AIBIIIS2 chalcopyrite (ch) family are completed by IR absorption and Raman scattering measurements. The ch extended Keating model is applied to these phonons. The experiments and calculations clarify the assignments of the Γ3-modes and the low-energy modes which originate from the transverse acoustic zincblende (zb) phonons. The central force constants between nearest neighbours αBS of the homopolar bonds are very large corresponding to the small bond lengths. On the other hand, the strong heteropolar A–S bonds yield very low αAS-values. The model parameters, which are determined by optical phonon fitting, also reproduce in a zb approximation the elastic moduli of AgGaS2. Die Spektren der langwelligen optischen Phononen in funf Verbindungen der AIBIIIS2-Chalkopyritfamilie (ch) werden durch IR-Absorptions- und Ramanmessungen vervollstandigt. Das ch-erweiterte Keating-Modell wird auf diese Phononen angewendet. Die Experimente und Berechnungen klaren die Bestimmungen der Γ3-Moden und der niederenergetischen Moden, die von den transversal-akustischen Zinkblendephononen (zb) abgeleitet werden. Die zentralen Kraftkonstanten αBS zwischen nachsten Nachbarn der homopolaren Bindungen sind sehr gros, was mit den kurzen Bindungslangen ubereinstimmt. Auf der anderen Seite liefern die stark heteropolaren A–S-Bindungen sehr niedrige αAS-Werte. Die Modellparameter, die durch Anpassung der optischen Phononen bestimmt werden, geben die Elastizitatskoeffizienten von AgGaS2 in der zb-Naherung richtig wieder.

The phonon spectra of ZnGeP2 and CdGeP2, determined by Raman scattering on single crystals at room and liquid nitrogen temperature, are presented. The close coincidence of the zone center phonon energies of ZnGeP2 with the corresponding τ, X, and W modes of its isoelectronic analogue, GaP, bears out the expected similarity of lattice vibrations in ternary chalcopyrite compounds and binary zincblende materials. Differences between ZnGeP, and CdGeP2 can be attributed to mass and force constant differences when Zn is substituted by the heavier Cd atom.

XPS and LEED measurements of the oxidation in air and thermal desorption on PbTe, SnTe and Pb 0.8 Sn 0.2 Te surfaces are presented. The initial cleaning of the surface for the oxidation experiments by Ar sputtering (3 kV) yields immediately a perfect, unreconstructed Pb 1− x -Sn x Te surface. The oxidation process is determined by the preferential oxidation of Sri. The surface is strongly depleted of tellurium and enriched with lead and especially tin. During thermal desorption tellurium oxide is lost first from the surface. Lead and tin oxide are too stable to become thermally desorbed during our heat treatment (350°C, 30 min). The oxidation and thermal desorption can be understood as a competing chemical reaction between the stable SnO 2 and the unstable TeO 2 .

The Gruneisen parameters γ τ of the most prominent τ phonons in CdSiP 2 , CuAlS 2 are presented. Concerning the sign and magnitude of γ τ , a separation into three groups of phonons can be observed. This result is compared with the γ values of the corresponding phonon branches of the analogue binaries in the zincblende structure. In addition, the τ phonon spectrum of CuGaS 2 is given.