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To determine cochlear duct mid-scalar length in normal cochleae and its role in selecting the correct peri-modiolar and mid-scalar implant length.
The study included 40 patients with chronic otitis media who underwent high-resolution computed tomography of the temporal bone. The length and height of the basal turn, mid-modiolar height of the cochlea, mid-scalar and lateral wall length of the cochlear duct, and the ‘X’ line (the largest distance from mid-point of the round window to the mid-scalar point of the cochlear canal) were measured.
Cochlear duct lateral wall length (28.88 mm) was higher than cochlear duct mid-scalar length (20.08 mm) (p < 0.001). The simple linear regression equation for estimating complete cochlear duct length was: cochlear duct length = 0.2 + 2.85 × X line.
Using the mid-scalar point as the reference point (rather than the lateral wall) for measuring cochlear duct mid-scalar length, when deciding on the length of mid-scalar or peri-modiolar electrode, increases measurement accuracy. Mean cochlear duct mid-scalar length was compatible with peri-modiolar and mid-scalar implant lengths. The measurement method described herein may be useful for pre-operative peri-modiolar or mid-scalar implant selection.
A massive die-off of benthic suspension feeders (BSF) covered by large amounts of sediments was observed along Prince Islands coasts (north-eastern Sea of Marmara) in August 2015. Alcyonarians, pennatulaceans, bivalves and sponges were severely affected. Many BSF probably died from burial and clogging of their feeding and respiratory apparatus. Of the gorgonian colonies, 66 ± 34% (mean ± SD) were dead, while 15 ± 16% (mean ± SD) displayed recent necrosis on the colony surface. In addition, histopathological and microbial examinations of the affected gorgonians and gold corals (Savalia savaglia) suggest that stress caused by sedimentation made them vulnerable to exploitation by consistently isolated opportunistic microorganisms. We isolated Vibrio splendidus and Vibrio neptunius from diseased gold coral colonies, but the bacterial isolates obtained from gorgonians could only be identified to genus Vibrio level. The presumably artificially introduced fungus Mucor circinelloides was common on both gold coral and gorgonians. This mould and opportunistic bacteria may have colonized BSF by taking advantage of low oxygen levels leading to impaired coral immune responses and thereby exacerbated the BSF mortality. Construction and landfill operations at Yassıada seem to be the greatest contributor to the observed sedimentation, as shown by silicate concentrations in nearby waters. These observations imply that preventive measures are necessary when construction operations take place in the vicinity of sensitive marine habitats.
The temporal change in soil organic carbon (SOC) was analysed over an 80-year period based on climate change predictions of four regional circulation models under the International Panel on Climate Change (IPCC) A1B emission scenario in the 21st century. A 20-year (1991–2010) set of observed climate data was used to form the baseline, and generate synthetic data for future scenario analyses. With increasing carbon dioxide (CO2) levels, and under continuous winter wheat production with conventional tillage at different nitrogen (N) input rates, three crop-soil models were used to study the temporal changes of SOC. Results indicated that soil carbon (C) generally decreased over the simulation period. In addition, increased N losses through leaching and denitrification were estimated. Decline in soil C under continuous mono-cropping systems indicated increased focus on N fertilization strategies. The results also suggested significant interactive effect of N input rate and climate variables on soil C and denitrification in response to climate change. The uncertainty was addressed by including the crop-soil models in a mixed-effect analysis so that the contribution of the models to the total variance of random variation was quantified. Statistical analysis showed that the crop-soil models are the main source for uncertainty in analysing soil C and N responses to climate change.
The response of grain yield, grain nitrogen (N), phenological development and evapotranspiration of winter wheat to climate change was analysed over an 80-year period based on climate change predictions of four regional circulation models (RCMs) under the IPCC (International Panel on Climate Change) A1B emission scenario for the 21st century using three process-based models; A 20-year set (1991–2010) of observed daily climate data from Aarslev, Denmark was used to form the baseline, from which the RCM data were generated. The simulation of crop growth was performed with increasing carbon dioxide (CO2) levels and under continuous mono-cropping system at different N input rates. Results indicated that grain yield and grain N will be reduced in the future despite increased CO2 concentration in the atmosphere. While the increased N input may increase yield, it will not increase grain N. The present study suggested that in Denmark, alternative strategies for organic N acquisition of plants must be developed. Statistical analyses showed that while the crop models were the main source of uncertainty in estimating crop performance indicators in response to climate change, the choice of RCM was the main source of uncertainty in relation to baseline estimations.
Healthcare workers (HCWs) lack familiarity with evidence-based guidelines for the prevention of healthcare-associated infections (HAIs). There is good evidence that effective educational interventions help to facilitate guideline implementation, so we investigated whether e-learning could enhance HCW knowledge of HAI prevention guidelines.
We developed an electronic course (e-course) and tested its usability and content validity. An international sample of voluntary learners submitted to a pretest (T0) that determined their baseline knowledge of guidelines, and they subsequently studied the e-course. Immediately after studying the course, posttest 1 (T1) assessed the immediate learning effect. After 3 months, during which participants had no access to the course, a second posttest (T2) evaluated the residual learning effect.
A total of 3,587 HCWs representing 79 nationalities enrolled: 2,590 HCWs (72%) completed T0; 1,410 HCWs (39%) completed T1; and 1,011 HCWs (28%) completed T2. The median study time was 193 minutes (interquartile range [IQR], 96–306 minutes)
The median scores were 52% (IQR, 44%–62%) for T0, 80% (IQR, 68%–88%) for T1, and 74% (IQR, 64%–84%) for T2. The immediate learning effect (T0 vs T1) was +24% (IQR, 12%–34%; P<.001), and a residual effect (T0 vs T2) of +18% (IQR 8–28) remained (P<.001). A 200-minute study time was associated with a maximum immediate learning effect (28%). A study time >300 minutes yielded the greatest residual effect (24%).
Moderate time invested in e-learning yielded significant immediate and residual learning effects. Decision makers could consider promoting e-learning as a supporting tool in HAI prevention.
Drought risk is considered to be among the main limiting factors for maize (Zea mays L.) production in the Northeast Farming Region of China (NFR). Maize yield data from 44 stations over the period 1961–2010 were combined with data from weather stations to evaluate the effects of climatic factors, drought risk and irrigation requirement on rain-fed maize yield in specific maize growth phases. The maize growing season was divided into four growth phases comprising seeding, vegetative, flowering and maturity based on observations of phenological data from 1981 to 2010. The dual crop coefficient was used to calculate crop evapotranspiration and soil water balance during the maize growing season. The effects of mean temperature, solar radiation, effective rainfall, water deficit, drought stress days, actual crop evapotranspiration and irrigation requirement in different growth phases were included in the statistical model to predict maize yield. During the period 1961–2010, mean temperature increased significantly in all growth phases in NFR, while solar radiation decreased significantly in southern NFR in the seeding, vegetative and flowering phases. Effective rainfall increased in the seeding and vegetative phases, reducing water deficit over the period, whereas decreasing effective rainfall over time in the flowering and maturity phases enhanced water deficit. An increase in days with drought stress was concentrated in western NFR, with larger volumes of irrigation needed to compensate for increased dryness. The present results indicate that higher mean temperature in the seeding and maturity phases was beneficial for maize yield, whereas excessive rainfall would damage maize yield, in particular in the seeding and flowering phases. Drought stress in any growth stage was found to reduce maize yield and water deficit was slightly better than other indicators of drought stress for explaining yield variability. The effect of drought stress was particularly strong in the seeding and flowering phases, indicating that these periods should be given priority for irrigation. The yield-reducing effects of both drought and intense rainfall illustrate the importance of further development of irrigation and drainage systems for ensuring the stability of maize production in NFR.
Crop production in the Northeast Farming Region of China (NFR) is affected considerably by variation in climatic conditions. Data on crop yield and weather conditions from a number of agro-meteorological stations in NFR were used in a mixed linear model to evaluate the impacts of climatic variables on the yield of maize (Zea mays L.), rice (Oryza sativa L.), soybean (Glycine max L. Merr.) and spring wheat (Triticum aestivum L.) in different crop growth phases. The crop growing season was divided into three growth phases based on the average crop phenological dates from records covering 1981 and 2010 at each station, comprising pre-flowering (from sowing to just prior to flowering), flowering (20 days around flowering) and post-flowering (10 days after flowering to maturity). The climatic variables were mean minimum temperature, thermal time (which is used to indicate changes in the length of growth cycles), average daily solar radiation, accumulated precipitation, aridity index (which is used to assess drought stress) and heat degree-days index (HDD) (which is used to indicate heat stress) were calculated for each growth phase and year. Over the 1961–2010 period, the minimum temperature increased significantly in each crop growth phase, the thermal time increased significantly in the pre-flowering phase of each crop and in the post-flowering phases of maize, rice and soybean, and HDD increased significantly in the pre-flowering phase of soybean and wheat. Average solar radiation decreased significantly in the pre-flowering phase of all four crops and in the flowering phase of soybean and wheat. Precipitation increased during the pre-flowering phase leading to less aridity, whereas reduced precipitation in the flowering and post-flowering phases enhanced aridity. Statistical analyses indicated that higher minimum temperature was beneficial for maize, rice and soybean yields, whereas increased temperature reduced wheat yield. Higher solar radiation in the pre-flowering phase was beneficial for maize yield, in the post-flowering phase for wheat yield, whereas higher solar radiation in the flowering phase reduced rice yield. Increased aridity in the pre-flowering and flowering phases severely reduced maize yield, higher aridity in the flowering and post-flowering phases reduced rice yield, and aridity in all growth phases reduced soybean and wheat yields. Higher HDD in all growth phases reduced maize and soybean yield and HDD in the pre-flowering phase reduced rice yield. Such effects suggest that projected future climate change may have marked effects on crop yield through effects of several climatic variables, calling for adaptation measures such as breeding and changes in crop, soil and agricultural water management.
The use of cold nasal packs on the nose and nape of the neck is currently recommended for patients with epistaxis as this is thought to induce reflex nasal vasoconstriction, which decreases the bleeding. There have been a few investigations on the effect of cold compress application to the nose, but none of these focused specifically on nasal cooling of the skin of the nose.
Acoustic rhinometry was performed to obtain baseline measurements. Nasal dorsal skin was then cooled with two ice packs that were held on the left and right side of the nose for a total of 10 minutes by the subjects. The rhinometry measurements were taken at the time of initial application (baseline), and after 5 and 10 minutes of ice pack application.
Comparisons of the first and second minimal cross-sectional area values, and total nasal cavity volume measurements revealed no statistical differences.
The results of this study indicate that one should be sceptical about the efficiency of cold compress application, which is frequently used in clinical practice in cases with epistaxis.
The organogenesis of the digestive system was described in the Amazonian pimelodid catfish species Pseudoplatystoma punctifer from hatching (3.5 mm total length, TL) to 41 days post-fertilization (dpf) (58.1 mm TL) reared at 28°C. Newly hatched larvae showed a simple digestive tract, which appeared as a straight undifferentiated and unfolded tube lined by a single layer of columnar epithelial cells (future enterocytes). During the endogenous feeding period, comprised between 20 and 96 h post-fertilization (3.5 to 6.1 mm TL), the larval digestive system experienced a fast transformation with the almost complete development and differentiation of most of digestive organs (buccopahrynx, oesophagus, intestine, liver and exocrine pancreas). Yolk reserves were not completely depleted at the onset of exogenous feeding (4 dpf, 6.1 mm TL), and a period of mixed nutrition was observed up to 6 to 7 dpf (6.8 to 7.3 mm TL) when yolk was definitively exhausted. The stomach was the organ that latest achieved its complete differentiation, characterized by the development of abundant gastric glands in the fundic stomach between 10 and 15 dpf (10.9 to 15.8 mm TL) and the formation of the pyloric sphincter at the junction of the pyloric stomach and the anterior intestine at 15 dpf (15.8 mm TL). The above-mentioned morphological and histological features observed suggested the achievement of a digestive system characteristic of P. punctifer juveniles and adults. The ontogeny of the digestive system in P. punctifer followed the same general pattern as in most Siluriform species so far, although some species-specific differences in the timing of differentiation of several digestive structures were noted, which might be related to different reproductive guilds, egg and larval size or even different larval rearing practices. According to present findings on the histological development of the digestive system in P. punctifer, some recommendations regarding the rearing practices of this species are also provided in order to improve the actual larval rearing techniques of this fast-growing Neotropical catfish species.
The Istanbul Strait (Bosphorus) is a part of the Turkish Straits System, connecting the Aegean Sea and the Black Sea. There are three cetacean species in the Strait, namely the harbour porpoise (Phocoena phocoena), the common dolphin (Delphinus delphis), and the bottlenose dolphin (Tursiops truncatus). To monitor the presence of the cetaceans, a fixed stereo passive acoustic monitoring system (A-tag) was deployed in the middle of the Strait from July 2009 to September 2010. In total 26,814 click trains were detected. Presence, direction and inter-click intervals of phonating cetaceans were measured. Most click trains were detected during the night time. Diel presence pattern was prominent in March and April. In spring, the cetaceans were concentrated in one specific direction from the fixed monitoring system. In contrast, they were found in all directions for the rest of the year. Short range sonar (inter-click intervals (ICIs) less than 50 ms) was commonly detected in spring. During the rest of the year ICIs could reach up to 150 ms. All these findings suggest that they were feeding or socializing in spring and mostly travelling in the other seasons. It is well known that pelagic fish such as sprat and bluefish start their migration from the Aegean Sea to the Black Sea in spring. This study suggests that the cetaceans use the middle part of the Strait for feeding on the pelagic fish in spring when the fish migration has just started.
In this paper we present results on solid state reactions between Ti and Si1−xGex alloys selectively deposited onto Si (100) substrates using rapid thermal annealing (RTA) for contact applications in novel device structures. Germanium concentrations of 0%, 30%, 50%, and 100% within the reacting Si1−xGex alloy are investigated. The Si1−xGex alloys (approximately 2500 ° thick) are deposited using rapid thermal chemical vapor deposition (RTCVD). Titanium is then deposited by evaporation. Sheet resistance measurements as a function of RTA temperature (10 second anneals) provide indications of various phases that occur during the reactions through the formation of constant sheet resistance plateaus. The RTA temperature required for the formation of a minimum resistivity phase is observed to increase for increasing Ge concentrations within the reacting Si1−xGex alloy. Using x-ray diffraction we have determined that for the reactions of Ti with Si the C49 TiSi2 metastable phase forms prior to the minimum resistivity C54 TiSi2 phase. For the reactions between Ti and Ge a minimum resistivity TiGe2 phase also with the C54 structure forms, however, this phase is preceeded not by a C49 TiGe2 structure, but by a Ti6Ge5 phase. The minimum resistivity phases for Ti reactions with 30% and 50% Ge Si1−xGex, alloy reactions also have a C54 structure with unit cell dimensions varying from that of TiSi2) to TiGe2 as the Ge concentration is increased. The grain structures for the reactions are investigated by cross-sectional transmission electron microscopy (XTEM). As the Ge concentration within the reacting alloy decreases the lateral grain size for the C54 structures increases. A self-aligned germanosilicide process is identified and used to fabricate raised, ultrashallow junctions with Ti(SiGe)2 (germanosilicide) contacts. Forward and reverse bias characterization of the junctions indicate that leakage current induced during silicidation can be eliminated using raised junctions with germanosilicide contacts.
To analyse patients with cholesteatoma undergoing canal wall down mastoidectomy together with ossicular reconstruction with a titanium prosthesis, in order to identify factors associated with hearing outcomes.
Retrospective review of 97 cases undergoing single-stage surgical management.
All patients underwent canal wall down mastoidectomy. Kurz titanium ossicular prostheses were used for ossicular chain reconstruction. Pre-operative and post-operative air conduction and bone conduction hearing thresholds were obtained at 500, 1000, 2000 and 3000 Hz.
The mean pure tone average improved from 46.02 ± 14.54 dB pre-operatively to 29.32 ± 14.64 dB post-operatively, for both total and partial ossicular replacement prosthesis groups combined. The mean air–bone gap improved from 30.38 ± 11.12 dB pre-operatively to 15.62 ± 9.65 dB post-operatively, for both groups combined.
Reconstruction with a titanium prosthesis offers good functional results when performed during canal wall down surgery for advanced cholesteatoma, as a single-stage procedure.
Mucormycosis is an opportunist, often lethal fungal infection which occurs in immunocompromised patients. We present our experience in 14 patients with this condition.
Patients and methods:
A retrospective chart review was conducted for 14 patients treated for rhinocerebral mucormycosis.
Nine patients had diabetes mellitus and six had a haematological malignancy. Nine patients had cutaneous and/or palatal necrosis. Eleven patients were treated with amphotericin B and five with liposomal amphotericin B. Endoscopic sinus surgery was performed in five patients with disease limited to the sinonasal cavity; nine patients underwent more extensive surgery. Five patients with disease limited to the sinonasal cavity survived, while nine patients with widely disseminated disease died. Five of the nine diabetic patients died, as did five of the six patients with haematological malignancy.
Patients with rhinocerebral mucormycosis spreading outside the sinonasal cavity have a poor prognosis.
In this work, low pressure chemical vapor deposition (LPCVD) of pure Ge and SixGe1-x on Si and SiO2 has been considered for new applications in future ultra large scale integration (ULSI) technologies. Depositions were performed in a lamp heated cold-wall rapid thermal processor (rapid thermal chemical vapor deposition -RTCVD) using thermal decomposition of GeH4 and SiH2Cl2 in a carrier gas of H2. It is shown that RTCVD of Ge on Si is highly selective with no deposition occuring on SiO2. The selectivity of Ge/Si depends on the amount of germane in the gas phase. The processes are relatively low temperature/high throughput processes suitable to single wafer manufacturing. In this paper, we review potential applications of Ge and SixGe1−x in future MOS processes. Specifically, Ge and SixGe1−x have been considered for three new applications: i) fabrication of raised source/drain structures where selective Ge or SixGe1−x is used as a sacrificial layer to eliminate silicon consumption during silicide formation (by forming a germanide), ii) Formation of ultra-shallow junctions in silicon using selectively deposited and implanted polycrystalline SixGe1−x as a diffusion source, iii) Formation of MOS gate structures with SixGe1−x gate electrodes for lower dopant activation temperatures and better threshold control.
In this study, we present characterization of Metal-Oxide-Semiconductor (MOS) capacitors fabricated on carbon (C14) implanted silicon substrates. Carbon was implanted at an energy of 50 keV with doses ranging from 1 × 1012 cm−2 to 4.1×1015 cm−2. Metal-Oxide-Silicon (MOS) capacitors were fabricated and used to determine the MOS capacitance-voltage (C-V) and capacitance-time (C-t) behavior. These measurements revealed a strong correlation between carrier lifetime and the carbon dose. Degradation in lifetime was observed for carbon dose levels as low as 4 × l012 cm−2. At carbon doses equal to and above 6.4 × l013 cm−2, extremely low generation lifetimes were obtained (∼ 10−7 sec). On the other hand, degradation in C-V characteristics was observed only for carbon doses above 2.7 × l014 cm−2. Below this dose, both flatband voltage and interface trap density of the carbon implanted samples were comparable to those of the monitors. Analysis of the samples by cross sectional transmission electron microscopy revealed the absence of extended defects even in samples with high carbon dose levels.
The low-temperature (20K) photoluminescence of InxGa1-xAs and InxGal-xAs - GaAs strained-layer superlattices (SLS's) grown by molecular beam epitaxy (MBE) is investigated. Data are presented for thick (bulk) epitaxial layers grown directly on GaAs and for relatively-thin (˜600Å) InxGa1-xAs layers under biaxial compression. Data are also presented for two series of SLS's. In the two series of SLS's, the InxGa1-xAs layer thickness (Lz) is held constant while only the GaAs layer thickness (LB) is varied. The photoluminescence (PL) spectra of the crystals are useful in analyzing the effects of biaxial strain, carrier confinement, and barrier layer thicknesses in SLS's. Results are compared with calculations based upon a modified Kronig-Penney model which incorporates the appropriate deformation potentials for SLS analysis. This type of analysis, in agreement with experimental data, suggests that the electron-to-light-hole transition can be lower in energy than the electron-to-heavy-hole transition in SLS's, depending upon layer thickness and crystal composition.
Various surface pre-cleaning processes for rapid thermal in-situ polysilicon/oxide/silicon stacked gate formation have been evaluated. MOS capacitors have been fabricated to assess the effects of surface pre-cleaning on the quality of both Rapid Thermal Oxide (RTO) and Rapid Thermal Chemical Vapor Deposition (RTCVD) oxide. Measurement results have shown that, 1) High temperature (≥ 900 °C) rapid thermal cleaning in Ar, H2 or high vacuum (10−8 Torr) ambients can lead to MOS gates with high leakage current if RTO is used to form the gate oxide, 2) The standard Huang clean and ultra-violet ozone (UV/O3) treatments can improve the film quality for both deposited and thermally grown oxide, and 3) Compared with RTO, the breakdown field of the RTCVD oxide is less dependent on the surface pre-cleaning treatment. These results indicate that silicon wafer surface cleaning techniques typically used for silicon epitaxial processes are not necessarily applicable to oxide film formation in RTP reactors.