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Genetic variation in feed efficiency may have a significant impact on sheep production in integrated crop livestock farming systems in dry areas, where the shortage and poor quality of feed is widespread. Thus, the present study was carried out to investigate the effects of sheep genotype and feed source on liveweight gain, feed conversion efficiency and dry matter (DM) intake in feedlot lambs finished on diets based on low-cost forages or a high-cost concentrated feed as a means of assessing the efficiency of this feeding system. Early weaned lambs of the purebred fat-tailed Akkaraman breed were compared with synthetic Anatolian Merino (0·80 German Mutton Merino×0·20 Native Akkaraman) breed. The lambs were kept in individual pens for 8 weeks and fed four diets: daily harvested forages of triticale (T), Hungarian vetch (HV), a triticale-Hungarian vetch mixture (T+HV), and a concentrate-based feed (CF). Lamb liveweight gain (LWG) was monitored during the early (18 April–16 May) and late (17 May–13 June) spring periods. Diet×period and diet×breed interactions were detected in LWG of the lambs. Lambs from both genotypes on the concentrate-based diet had higher liveweight gains, DM intakes and better feed conversion ratios compared with lambs finished on the forage-based diets. The LWG of lambs offered triticale forage decreased from 177 g/head/day in the early spring to 95 g/head/day in the late spring period, as plant maturity increased. Liveweight gains did not change for the other forage rations during the same period. The LWG of Akkaraman lambs were similar for both the early (189 g/head/day) and the late (183 g/head/day) spring periods, whereas Anatolian Merino lambs gained 41 g/head/day less LW and had 3·8 higher feed conversion rate for the late spring period compared with the early spring period. The present study showed that fat-tailed Akkaraman lambs were better able to utilize forages with low nutritive value compared to Anatolian Merino lambs, and may be better suited to semi-arid areas, where crop and livestock are highly integrated in the farming system.
Deafness may be one of the factors that leads to a change in sexual function. This study aimed to assess sexual function, in particular erectile dysfunction, in male patients with hearing loss.
Materials and methods:
We studied two groups: (1) adult men with acquired, bilateral, sensorineural hearing loss, and (2) healthy, adult, married men demonstrated to have normal hearing levels, as the control group. Sexual function was assessed using the International Index of Erectile Functions questionnaire, and quality of life using the 36-Item Short-Form Health Survey.
There was a statistically significant difference between the groups regarding the International Index of Erectile Functions questionnaire results (p <0.001), both for each of the five questionnaire domain scores and for the total score.
Our results indicate that men with mild or moderate sensorineural hearing loss have poorer sexual health.
To compare mucosal and bony measurements in patients with congenital and traumatic nasal septum deviation and compensatory inferior turbinate hypertrophy.
The study examined 50 patients with nasal septum deviation (25 congenital and 25 traumatic) and compensatory inferior turbinate hypertrophy in the contralateral nasal cavity, confirmed by computed tomography.
The study compared inferior turbinate measurements on the concave and convex sides of the septum, in the congenital and traumatic groups. Measurements comprised: the shortest distance from the median line to the medial border of the conchal bone; the distances from the most medial part of the conchal mucosa and the conchal bone to the lateral line; the projection angle of the inferior turbinate; and the widest parts of the whole inferior turbinate and the inferior turbinate conchal bone. The differences between the concave and convex side measurements were compared in the congenital group versus the traumatic group; for three measurements, the difference between these two groups was statistically significant (p < 0.05).
The present study findings suggest that the conchal bone has a marked influence on nasal patency in patients with congenital septal deviation. These findings supported the decision to excise the inferior turbinate bone at the time of septoplasty, especially when treating congenital septal deviation.
Sweet cherries can be grafted on a wide range of rootstocks belonging to Prunus avium, Prunus cerasus, Prunus mahaleb, Prunus angustifolia or hybrids of different Prunus species. Identification of Prunus rootstocks using morphological traits is almost impossible particularly during the dormant season. However, molecular analysis carried out on actively growing shoot tips, leaves or dormant buds provides good opportunity to reliably distinguish rootstocks. In this study, DNA was extracted from the leaves of a total of 184 sweet cherry rootstock candidates belonging to P. avium L., P. cerasus L., P. mahaleb L. and P. angustifolia L. previously selected from the north-western part of Turkey. The rootstock candidates were tested with ten simple sequence repeat (SSR) primers, developed for the Prunus genus. The primers successfully identified all rootstock candidates. The results showed that the number of alleles per locus ranged from 10 (UDAp-401, UCD-CH21 and CPSCT010) to 20 (UCD-CH31) with an average of 13.3 alleles per locus, indicating that the SSRs were highly informative. Unweighted Pair-Group Method with Arithmetic mean analysis demonstrated that P. avium accessions are closely related to P. cerasus. The reference rootstocks were clustered with their associated botanical species.
The position of the dark fermi level in hydrogenated amorphous silicon (a-Si:H) is important in determining its electrical properties and is a key parameter in the detailed modelling of materials and devices. The activation energies of conductivities have been investigated on intrinsic a-Si:H films from various laboratories where the slopes of the Arrhenius plots have ranged from 0.27 eV to 0.87 eV. In many cases, marked differences are found between the results obtained from two and four probe measurements, highlighting the importance of the four probe configuration. Results are presented which help to explain the scatter in the measured activation energies between intrinsic films of a-Si:H. Differences in the activation energies are discussed in terms of current limiting processes which act in series with the material bulk resistance. It will be shown that the conductivity of the film and the contact are key factors in assessing whether the position of the fermi level can be accurately determined from a two contact measurement.
Dark J-V characteristics of Ni Schottky diodes on a-Si:H films of various thicknesses were measured as a function of device temperature. Room-temperature photoconductivity and sub-bandgap absorption v. wavelength measurements of the intrinsic layers were also performed. Detailed numerical modelling was employed to determine the nature, density and energy distribution of sub- bandgap states. Best-fit modelling of photoconductivity, sub-bandgap absorption and dark JR-VR indicates that Nc=Nv=2.5×1020 cm-3, vR=2×106 cm/s, μn=33 cm2/V-s and μp=0.15 cm2/V-s for these films. It is found that a joint thermionic emission-drift/diffusion mechanism, as envisaged by Crowell and Sze, appears to be the most accurate picture of electron transport in Schottky diodes on intrinsic a-Si:H films.
The optical properties of solar cell grade hydrogenated amorphous silicon (a-Si:H), silicon germanium (a-SiGe:H) and silicon carbon (a-SiC:H) alloy thin films have been investigated over a wide photon energy range (0.8–4.8 eV) using a combination of subgap photoconductivity, reflection and transmission, and spectroscopie ellipsometry techniques in order to obtain accurate optical functions for solar cell modelling. Studies on films with thicknesses ranging from a few hundred Å to a few microns show that the optical spectra obtained by the different techniques agree closely over the energy ranges of overlap and display no thickness dependence from the Urbach tail energies and above. Thus, the results appear to be free of measurement and sample related artifacts. Three different methods provide a common value for the optical gap within ±0.02 eV and the result for a-Si:H is ∼0.1 eV below the mobility gap.
The flame retardancy of nylon 6/laponite and nylon 6/montmorillonite nanocomposites was investigated. The pronounced effect of layered silicates on heat release and mass loss rates of nylon 6 was examined. We found that nylon 6/laponite has 46 % and nylon 6/montmorillonite has 52.5 % lower peak heat release rates than that of neat nylon 6. The 6.5 % difference between the peak heat release rates of laponite- and montmorillonite-based nanocomposites was attributed to differences in aspect ratio and surface charge density of the nanoparticles.
The barrier properties of nanocomposite chars was evaluated by examining the peak heat release and mass loss rate reductions of stacks of layers, with the bottom layer being neat nylon 6 polymer and the top layers being nanocomposites that formed chars during the experiments. We observed that the peak heat release rate of a 10×10×0.3 cm neat nylon 6 slab was reduced by about 45 % when protected with a char-forming nylon 6/montmorillonite slab of same dimensions. The dramatic reduction of the peak heat release rate of neat nylon 6 when covered with a nanocomposite char was consistent with the notion that the flame retardancy of polymer/clay nanocomposites is affected by the (thermal and/or mass) barrier properties of the char. In order to test the thermal insulation of the char, temperature profiles of the layered samples were measured during cone calorimeter experiments. We observed that the nanocomposite char that brought about a 44.5 % reduction in peak heat release and mass loss rates reduced the heating rate of the same neat nylon 6 by about 31.2 %. The reduction in the heating rate increased with the amount of nanocomposite char formed.
The dependence of electrical resistivity on specimen temperature and imposed tensile strains was determined for shape memory polyurethane (SMPU) composites of carbon nanofiber (CNF), oxidized carbon nanofiber (ox-CNF), and carbon black (CB). The SMPU composites with crystalline soft segments were synthesized from diphenylmethane diisocyanate, 1,4-butanediol, and poly(caprolactone)diol in a low-shear chaotic mixer and in an internal mixer. The materials synthesized in the chaotic mixer showed higher soft segment crystallinity and lower electrical percolation thresholds. The soft segment crystallinity reduced in the presence of CNF and ox-CNF; although the reduction was lower in the case of ox-CNF. The composites of CB showed pronounced positive temperature coefficient (PTC) effects which in turn showed a close relationship with non-linear thermal expansion behavior. The composites of CNF and ox-CNF did not exhibit PTC effects due to low levels of soft segment crystallinity. The resistivity of composites of CNF and ox-CNF showed weak dependence on strain, while that of composites of CB increased by several orders of magnitude with imposed tensile strain. A corollary of this study was that a high level of crystallinity may cause a PTC effect and prevent any actuation through resistive heating. However, a carefully tailored compound which has reduced crystallinity and which requires minimum amount of filler may prevent PTC phenomenon and could supply necessary electrical conductivity over the operating temperature range, while offering enough soft segment crystallinity and rubberlike properties for excellent shape memory function.
Electron mobilities were studied as a function of thin-film growth conditions in hot wall epitaxially grown C60 based field-effect transistors. Mobilities in the range of ∼ 0.5 to 6 cm2/Vs are obtained depending on the thin-film morphology arising from the initial growth conditions. Moreover, the field-effect transistor current is determined by the morphology of the film at the interface with the dielectric, while the upper layers are less relevant to the transport. At high electric fields, a non-linear transport has been observed. This effect is assigned to be either because of the dominance of the contact resistance over the channel resistance or because of the gradual move of the Fermi level towards the band edge as more and more empty traps are filled due to charge injection.
We have fabricated heterojunction solar cells comprising active layers of
perylene diimide (PDI) or perylene bisbenzimidazole (CONPER, conjugated
perylene dye) as electron acceptor and ZnPC as donor. Bilayer solar cells
were produced by successive evaporation of zinc phthalocyanine (ZnPC) and
perylene diimide (PDI) or perylene bisbenzimidazole (CONPER) on glass
substrates coated with indium doped tin oxide. Active layers with
different thickness were evaporated. The bilayer cells were characterized
under simulated AM 1.5 illumination (100 mW/cm2). The best results were
obtained for the device structure of ITO/PEDOT/ZnPC (40 nm)/perylene
bisbenzimidazole (60 nm)/Al (70 nm).
In this work low bandgap thienylenevinylene and phenylene
vinylene copolymers, which possess either 3,4-ethylenedioxylthiophene (EDOT)
groups (Polymer 1) or long alkyl side chains (Polymer 2)
were investigated and compared in photoinduced electron transfer properties
and photovoltaic performance. The results show that the interaction of the
photoexcited polymers with an electron acceptor ([6,6]-phenyl C61 – butyric
acid methyl ester (PCBM)) leads to charge generation and transfer for both
polymers. We found that the long alkyl side chain in Polymer 2
instead of the EDOT group in Polymer 1 enhances the open circuit
but lowers the short circuit current (
. On the
other hand the long alkyl side chain in Polymer 2 significantly
improves the solubility and enhances processability for solar cells
fabrication. Optimization of the chemical structure of these low bandgap
polymers could lead to a spectral improvement of photocurrent generation in
organic solar cells.
Background: In this prospective, randomized, double-blind, controlled study, we investigated the sensory, motor and analgesic block characteristics of S(+) ketamine, fentanyl and saline given intrathecally (IT) in addition to 0.5% plain bupivacaine (10 mg) for spinal analgesia. Methods: Ninety ASA I or II adult patients undergoing Caesarean section were randomly allocated to receive 1.0 mL of 0.9% saline in Group S (n = 30), 0.05 mg kg−1 of S(+) ketamine (1.0 mL) in Group K (n =30) or 25 μg (1.0 mL) of fentanyl in Group F (n =30) following 10 mg of plain bupivacaine 0.5% IT. We recorded onset and duration of sensory and motor block, time to reach the maximal dermatomal level of sensory block and duration of spinal analgesia. Results: The onset time of sensory and motor block was significantly shorter in Groups K and F than in Group S (P < 0.014). Their duration was significantly longer in Group F than in Groups K and S (P < 0.009). The time to reach the maximal dermatomal level of sensory block was significantly shorter in Groups K and F than in Group S (P < 0.001). The duration of spinal analgesia was significantly longer in Group F than in Groups K and S (P < 0.001). Conclusion: In patients undergoing Caesarean section with spinal analgesia, the addition of S(+) ketamine (0.05 mg kg−1) IT to 10 mg of spinal plain bupivacaine (0.5%) led to rapid onset of both sensory and motor blockade and enhanced the segmental spread of spinal block without prolonging the duration of spinal analgesia, whereas fentanyl provided prolonged analgesia.
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