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Objectives: Audiometric testing typically does not include frequencies above 8 kHz. However, recent research suggests that extended high-frequency (EHF) sensitivity could affect hearing in natural communication environments. Clinical assessment of hearing often employs pure tones and frequency-modulated (FM) tones interchangeably regardless of frequency. The present study was designed to evaluate how the stimulus chosen to measure EHF thresholds affects estimates of hearing sensitivity., Design: The first experiment used standard audiometric procedures to measure 8- and 16-kHz thresholds for 5- to 28-year olds with normal hearing in the standard audiometric range (250 to 8000 Hz). Stimuli were steady tones, pulsed tones, and FM tones. The second experiment tested 18- to 28-year olds with normal hearing in the standard audiometric range using psychophysical procedures to evaluate how changes in sensitivity as a function of frequency affect detection of stimuli that differ with respect to bandwidth, including bands of noise. Thresholds were measured using steady tones, pulsed tones, FM tones, narrow bands of noise, and one-third-octave bands of noise at a range of center frequencies in one ear., Results: In experiment 1, thresholds improved with increasing age at 8 kHz and worsened with increasing age at 16 kHz. Thresholds for individual participants were relatively similar for steady, pulsed, and FM tones at 8 kHz. At 16 kHz, mean thresholds were approximately 5 dB lower for FM tones than for steady or pulsed tones. This stimulus effect did not differ as a function of age. Experiment 2 replicated this greater stimulus effect at 16 kHz than at 8 kHz and showed that the slope of the audibility curve accounted for these effects., Conclusions: Contrary to prior expectations, there was no evidence that the choice of stimulus type affected school-age children more than adults. For individual participants, audiometric thresholds at 16 kHz were as much as 20 dB lower for FM tones than for steady tones. Threshold differences across stimuli at 16 kHz were predicted by differences in audibility across frequency, which can vary markedly between listeners. These results highlight the importance of considering spectral width of the stimulus used to evaluate EHF thresholds., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

The fundamental parameters of majority and minority charge carriers-including their type, density and mobility-govern the performance of semiconductor devices yet can be difficult to measure. Although the Hall measurement technique is currently the standard for extracting the properties of majority carriers, those of minority carriers have typically only been accessible through the application of separate techniques. Here we demonstrate an extension to the classic Hall measurement-a carrier-resolved photo-Hall technique-that enables us to simultaneously obtain the mobility and concentration of both majority and minority carriers, as well as the recombination lifetime, diffusion length and recombination coefficient. This is enabled by advances in a.c.-field Hall measurement using a rotating parallel dipole line system and an equation, Δμ H  = d(σ 2 H)/dσ, which relates the hole-electron Hall mobility difference (Δμ H ), the conductivity (σ) and the Hall coefficient (H). We apply this technique to various solar absorbers-including high-performance lead-iodide-based perovskites-and demonstrate simultaneous access to majority and minority carrier parameters and map the results against varying light intensities. This information, which is buried within the photo-Hall measurement 1,2 , had remained inaccessible since the original discovery of the Hall effect in 1879 3 . The simultaneous measurement of majority and minority carriers should have broad applications, including in photovoltaics and other optoelectronic devices.

High nonradiative recombination, low diffusion length and band tailing are often associated with a large open circuit voltage deficit, which results in low efficiency of Cu 2 ZnSnS 4 (CZTS) solar cells. Recently, cation substitution in CZTS has gained interest as a plausible solution to suppress these issues. However, the common substitutes, Ag and Cd, are not ideal due to their scarcity and toxicity. Other transition-metal candidates (e.g., Mn, Fe, Co, or Ni) are multivalent, which may form harmful deep-level defects. Magnesium, as one of the viable substitutes, does not have these issues, as it is very stable in +2 oxidation state, abundant, and nontoxic. In this study, we investigate the effect of Mg incorporation in sulfur-based Cu 2 ZnSnS 4 to form Cu 2 Mg x Zn 1- x SnS 4 by varying x from 0.0 to 1.0. These films were fabricated by chemical spray pyrolysis and the subsequent sulfurization process. At a high Mg content, it is found that Mg does not replace Zn to form a quaternary compound, which leads to the appearance of the secondary phases in the sample. However, a low Mg content (Cu 2 Mg 0.05 Zn 0.95 SnS 4 ) improves the power conversion efficiency from 5.10% (CZTS) to 6.73%. The improvement is correlated to the better carrier-transport properties, as shown by a lesser amount of the ZnS secondary phase, higher carrier mobility, and shallower acceptor defects level. In addition, the Cu 2 Mg 0.05 Zn 0.95 SnS 4 device also shows better charge-collection property based on the higher fill factor and quantum efficiency despite having lower depletion width. Therefore, we believe that the addition of a small amount of Mg is another viable route to improve the performance of the CZTS solar cell.

In cavity quantum electrodynamics, optical emitters that are strongly coupled to cavities give rise to polaritons with characteristics of both the emitters and the cavity excitations. We show that carbon nanotubes can be crystallized into chip-scale, two-dimensionally ordered films and that this material enables intrinsically ultrastrong emitter-cavity interactions: Rather than interacting with external cavities, nanotube excitons couple to the near-infrared plasmon resonances of the nanotubes themselves. Our polycrystalline nanotube films have a hexagonal crystal structure, ∼25-nm domains, and a 1.74-nm lattice constant. With this extremely high nanotube density and nearly ideal plasmon-exciton spatial overlap, plasmon-exciton coupling strengths reach 0.5 eV, which is 75% of the bare exciton energy and a near record for room-temperature ultrastrong coupling. Crystallized nanotube films represent a milestone in nanomaterials assembly and provide a compelling foundation for high-ampacity conductors, low-power optical switches, and tunable optical antennas., Competing Interests: The authors declare no conflict of interest.

Selenium was used in the first solid state solar cell in 1883 and gave early insights into the photoelectric effect that inspired Einstein's Nobel Prize work; however, the latest efficiency milestone of 5.0% was more than 30 years ago. The recent surge of interest towards high-band gap absorbers for tandem applications led us to reconsider this attractive 1.95 eV material. Here, we show completely redesigned selenium devices with improved back and front interfaces optimized through combinatorial studies and demonstrate record open-circuit voltage (V OC ) of 970 mV and efficiency of 6.5% under 1 Sun. In addition, Se devices are air-stable, non-toxic, and extremely simple to fabricate. The absorber layer is only 100 nm thick, and can be processed at 200 ˚C, allowing temperature compatibility with most bottom substrates or sub-cells. We analyze device limitations and find significant potential for further improvement making selenium an attractive high-band-gap absorber for multi-junction device applications.Wide band gap semiconductors are important for the development of tandem photovoltaics. By introducing buffer layers at the front and rear side of solar cells based on selenium; Todorov et al., reduce interface recombination losses to achieve photoconversion efficiencies of 6.5%.

A summary and analysis have been carried out on data from over 6000 instances of flystrike in sheep in NZ, over a 16-year period, using a self-referral system where farmers submitted larvae and related information. The study covered a period of establishment and subsequent countrywide spread of the exotic blowfly, Lucilia cuprina. Comparisons are drawn between flystrike as it was perceived by surveys carried out before the 1940s, and the current situation with L. cuprina as an added major impediment. Briefly, the main differences are an increase in the prevalence of flystrike, changes in the representation and relative influence of individual primary blowfly species, an extension of the flystrike 'season', and an apparent increase in the importance of footrot as a factor predisposing to flystrike. Otherwise, flystrike is still primarily a disease of ewe lambs that are struck predominantly around the tail and perineum, mainly because of faecal staining.

Based on the Ehrenfest theorem, an equation of motion that takes relaxation into account has been presented in wave-function theory, and the resulting response functions are nondivergent in the off-resonant as well as the resonant regions of optical frequencies. The derivation includes single- and multideterminant reference states. When applied to electric dipole properties, the response functions correspond to the phenomenological sum-over-states expressions of Orr and Ward [Mol. Phys. 20, 513 (1971)] for polarizabilities and hyperpolarizabilities of an isolated system. A universal dispersion formula is derived for the complex second-order response function. Response theory calculations are performed on lithium hydride and para-nitroaniline for off-resonant and resonant frequencies in the electro-optical Kerr effect and second-harmonic generation.

It has been proposed that specific language impairment (SLI) is caused by an impairment of auditory processing, but it is unclear whether this problem affects temporal processing, frequency discrimination (FD), or both. Furthermore, there are few longitudinal studies in this area, making it hard to establish whether any deficit represents a developmental lag or a more permanent deficit. To address these issues, the authors retested a group of 10 children with SLI and 12 control children first tested 42 months previously. At Time 1, the children with SLI (between 9 and 12 years of age) had significantly elevated FD thresholds compared to the matched controls. At Time 2, the thresholds of both groups had improved, but the children with SLI still had poorer FD thresholds than those of the controls. To assess temporal resolution, auditory backward masking was measured and it was found that most of the children with SLI performed as well as the controls, but 2 children had exceptionally high thresholds. There was also greater variability among the children with SLI compared to that measured among the controls on the FD task. These studies indicate considerable heterogeneity in auditory function among children with SLI and suggest that, as with auditory temporal deficits, difficulties in FD discrimination are important in this population.

Our new simple method for calculating accurate Franck-Condon factors including nondiagonal (i.e., mode-mode) anharmonic coupling is used to simulate the C2H4+X2B3u<--C2H4X1A(g) band in the photoelectron spectrum. An improved vibrational basis set truncation algorithm, which permits very efficient computations, is employed. Because the torsional mode is highly anharmonic it is separated from the other modes and treated exactly. All other modes are treated through the second-order perturbation theory. The perturbation-theory corrections are significant and lead to a good agreement with experiment, although the separability assumption for torsion causes the C2D4 results to be not as good as those for C2H4. A variational formulation to overcome this circumstance, and deal with large anharmonicities in general, is suggested.

An efficient new procedure for calculating Franck-Condon factors, based on the direct solution of an appropriate set of simultaneous equations, is presented. Both Duschinsky rotations and anharmonicity are included, the latter by means of second-order perturbation theory. The critical truncation of basis set is accomplished by a build-up procedure that simultaneously removes negligible vibrational states. A successful test is carried out on ClO2 for which there are experimental data and other theoretical calculations., ((c) 2004 American Institute of Physics)

Purpose: To determine the weighted average sensitivity of magnetic resonance (MR) imaging in the prospective detection of acute neck injury and to compare these findings with those of a comprehensive conventional radiographic assessment., Materials and Methods: Conventional radiography and MR imaging were performed in 199 patients presenting to a level 1 trauma center with suspected cervical spine injury. Weighted sensitivities and specificities were calculated, and a weighted average across eight vertebral levels from C1 to T1 was formed. Fourteen parameters indicative of acute injury were tabulated., Results: Fifty-eight patients had 172 acute cervical injuries. MR imaging depicted 136 (79%) acute abnormalities and conventional radiography depicted 39 (23%). For assessment of acute fractures, MR images (weighted average sensitivity, 43%; CI: 21%, 66%) were comparable to conventional radiographs (weighted average sensitivity, 48%; CI: 30%, 65%). MR imaging was superior to conventional radiography in the evaluation of pre- or paravertebral hemorrhage or edema, anterior or posterior longitudinal ligament injury, traumatic disk herniation, cord edema, and cord compression. Cord injuries were associated with cervical spine spondylosis (P < .05), acute fracture (P < .001), and canal stenosis (P < .001)., Conclusion: MR imaging is more accurate than radiography in the detection of a wide spectrum of neck injuries, and further study is warranted of its potential effect on medical decision making, clinical outcome, and cost-effectiveness.

Groups of ten louse-naive lambs were infested with one, ten or 100 female Bovicola ovis and killed 84 days later when an examination of their pelts was made to detect cockle. In a second experiment groups of ten lambs were infested with ten or 100 female B. ovis and groups of lambs were killed every fortnight up to 84 days post-infestation. The pelts were examined in order to detect the earliest time at which cockle could be detected following a louse infestation. Cockle is a nodular condition of the skin arising in response to infestation with B. ovis and is possibly a hypersensitivity on the part of some sheep to antigens of louse origin. In the first experiment cockle did not develop in lambs that had remained louse free or which had been initially infested with one louse. However, five of ten lambs that had been infested with ten lice and all lambs that had been infested with 100 lice developed cockle. In general cockle severity was positively related to the size of the terminal louse population. Group mean louse counts only slightly exceeded the initial infestation in the lambs infested with either ten or 100 lice, and were less than the initial infestation in lambs given only one louse. In the second experiment cockle was first seen 54 days post-infestation, but only in sheep infested initially with 100 lice.

Between 1920 and 1930, four species of parasitoid Hymenoptera (Tachinaephagus zealandicus, Alysia manducator, Nasonia vitripennis and Brachymeria ucalegon) were imported to New Zealand as an aid in the control of the blowflies causing myiasis in sheep (flystrike). Their long-term effects have never been investigated and the extent to which they were successful in establishing and enlarging their ranges has been given scant regard over the last 60 years. A long-term epidemiological study of flystrike in New Zealand between 1984 and 1996 obtained 4061 samples of blowfly larvae from flystruck sheep and carrion and overall 1.1% of these larval samples (most from the North Island) were found to be parasitized. Tachinaephagus zealandicus and A.manducator were present in field strikes, together with the endemic Aphaereta aotea recently found to be a parasite of calliphorids. The endemic species Phaenocarpa antipoda was found in association with carrion but not flystrike. Neither N.vitripennnis nor B.ucalegon were isolated from larvae in field strikes, the former because it parasitizes only pupae and the latter may be extinct as it has not been sighted since its introduction in 1919. It is concluded that if parasitoid wasps are able to locate and parasitize blowfly larvae on struck sheep, then their parasitism rate on more accessible larvae on carcases may be correspondingly greater. For this reason their scope for use in integrated management of flystrike could be increased by culturing and field release.

Pelts from lambs submitted to an abattoir were obtained at monthly intervals from December to August. One half of each freshly flayed pelt was examined for cockle, lice (Bovicolu ovis) and dermatophilosis, and the observations compared with defects attributable to cockle and dermatophilosis in the corresponding pickled half-pelts. Formalin-fixed samples from pelts identified as having cockle were examined microscopically. Cockle was not detected macroscopically in flayed half-pelts despite being obvious in 4% of the pelts after pickling. Lice were detected in 17% of the flayed half-pelts. Dermatophilosis occurred in 12% of flayed half-pelts, presenting most commonly as small lesions in the dorsal midline regions of the lambs. However, only 4% of pickled half-pelts showed defects attributable to dermatophilosis. In other groups of lambs, cockle was detected in vivo by examining the skin over the upper shoulder region after close shearing of the wool. This method of detection showed sensitivity of 80% and specificity of 100%. The results of this work provide a basis for the monitoring of dermatophilosis and cockle in live lambs.

Sheep naturally infested with the biting louse, Bovicola ovis were treated with a range of organophosphorus and synthetic pyrethroid dip formulations. The sheep were killed 42 days after treatment and the pelts examined for evidence of cockle, a nodular condition that appears in some sheep as a response to the presence of lice. Sheep treated to saturation with dip formulations produced more high quality pelts than did sheep treated with low volume, pour-on or spray-on dips. These differences are suspected to arise because louse populations decline more slowly after treatment with pour-ons or spray-ons than with saturation dips. The removal of lice and regression of cockle resulted in a high percentage of first grade pickled pelts. However, processing through to the dyed crust leather stage highlighted lesions in the same pelts that were not apparent at the pickle stage and lead to a substantial increase in the number of downgraded pelts.

The prevalence and severity of cockle, a sheep pelt defect characterised by raised lumps, was assessed on lambs that were either louse-infested (Bovicola ovis) or louse-free at birth. Assessments were made on pickled pelts, 10 months after the lambs had entered the trial. Lambs kept free of lice did not develop cockle, whereas the defect was common in lambs (about 90%) that were infested with lice. There was a direct correlation between louse scores and cockle, high louse scores being associated with a more severe degree of cockle. The results give support to the strong causal relationship between B. ovis and cockle, but questions such as the minimum number of lice needed to cause cockle and the time required for cockle to develop still need to be answered.

Purpose: To reexamine the blood patch technique in a laboratory model of lung biopsy free of confounding clinical variables., Materials and Methods: An equine model of lung biopsy was developed with an excised lobe connected to an insufflation bulb and pressure monitor. Patched and control unpatched punctures were made in the lung surface, and the pressure within the lung was raised to the maximum achievable. Whether air leakage from the puncture sites could be induced was determined and, if so, at what pressure it occurred., Results: At statistical analysis with the Kaplan-Meier test and the Cox proportional hazards regression model, the difference between failure of the patched and unpatched punctures was statistically significant (P < .0001)., Conclusion: The blood patch technique is effective in the laboratory setting and deserves reevaluation in a clinical series with updated biopsy techniques.

Purpose: To develop a neural network to calculate skeletal age based on measurements taken from digitized hand radiographs., Materials and Methods: From a database of 521 hand radiographs obtained in healthy patients, four parameters were calculated from seven linear measurements and were used to train a neural network, with use of the jackknife method, to calculate skeletal age. The results were compared with those of an experienced pediatric radiologist using a standard pediatric skeletal atlas., Results: The mean difference from biologic age for the neural network was -0.261 years +/- 1.82 (standard deviation) and for the radiologist, -0.232 years +/- 1.54; this difference was not significantly different (P = .67, Wilcoxon signed rank test). Skeletal age determined by the neural network was closer to the biologic age than that assigned by the radiologist in 243 of 521 cases (47%)., Conclusion: A simple neural network may assist radiologists in the assessment of skeletal age.

A defect of sheep pelts known as cockle, detectable after depilation, but usually first noted only in the pickled pelt or tanned stage of processing, was studied to establish causal factor(s) and effective treatments. In addition, data on the histology and seasonal prevalence of the disease were obtained. Samples collected soon after slaughter from pelts identified at the pickled pelt stage as having cockle, had a superficial dermatitis with infiltration of eosinophils. This may represent an immediate hypersensitivity reaction of the sheep to lice. Treatments of sheep with either insecticides, disinfectants or shearing showed that where biting lice (Bovicola ovis) were removed, cockle lesions had either disappeared or regressed on pickled pelts. In Trial 1 diazinon reduced cockle prevalence and severity substantially; cypermethrin had a less pronounced effect. In Trial 2 diazinon, cypermethrin, Hibitane and Savlon were equally effective in reducing biting louse numbers as shown by counts of lice at 35 and 63 days post-treatment. Reduction of cockle on pelts from sheep slaughtered at 39 days post-treatment was achieved best by both diazinon and shearing. Examination of other pelts at 67 days post-treatment showed diazinon and Hibitane to be equally effective in reducing cockle. Furthermore, shearing in the absence of insecticides reduced the severity and extent of lesions on cockled pelts. The diazinon excipient and zinc sulphate were consistently poor at removing lice and reducing cockle prevalence and severity. The results have important implications for the leather industry in that shearing and good dipping practice with appropriate chemicals at the right time can lead to improved pelt quality. However, an incentive scheme for farmers, and a means of identifying individual pelts to the farms or origin, are both necessary before a marked improvement is likely to occur.

The comparative efficacy of 13 of the sheep dips currently registered in New Zealand was investigated using sheep infested with the louse Bovicola ovis and carrying wool which was about 10 cm long at the shoulder. With the exception of one synthetic pyrethroid pour-on formulation, all products were able to effect a significant reduction in louse populations, relative to untreated controls, for 37 days after treatment. Only four products proved capable of eradicating lice and preventing their re-establishment up to 37 days after treatment. Variations in manufacturers' recommendations relating to the length of wool at dipping, and mode of application of dips are discussed in relation to the results.

Two synthetic pyrethroid (cypermethrin) based pour-on insecticide formulations, with high cis/trans isomer ratios (80:20) but differing in their respective active ingredient concentrations and solvent component(s), were applied to sheep infested with the biting-louse, Bovicola ovis. All treated sheep were penned with louse-infested sheep 9,12 and 15 weeks after the insecticide was applied. The 2% cypermethrin formulation achieved a higher level of control than the 1.25% cypermethrin formulation at each challenge interval when applied 12 weeks after shearing. The 2% cypermethrin formulation provided 97-100% control of lice from 4 to 16 weeks after application on sheep shorn 6 or 12 weeks prior to treatment. The 1.25% cypermethrin formulation provided 85% control of lice 4 weeks after application on sheep shorn 12 weeks prior to treatment, the level of control increasing to a maximum of 100% by week 9, and declining thereafter. The 2% cypermethrin formulation may provide a better level of control in long-woolled sheep than 1.25% cypermethrin, by compensating for the diluent effect of lipid.

A single, artificially-induced fly-strike with Lucilia sericata larvae was associated with a rapid (decline in food intake in sheep, with a consequent reduction in liveweight. Loss of weight ranged from 0.5 to 5.5 kg over four to six days and recovery to pre-infestation liveweight took three to 36 days. Pair-fed, uninfested partners of these sheep also showed a reduction in liveweight, whereas uninfested sheep in some experiments fed ad libitum showed either little change or a gain in liveweight over the same period. In general, maggot infested sheep took less time to regain weight than did their pair-fed partners although the weight lost as a proportion of initial weight was similar in both groups. Loss of appetite alone would appear to account for these events.

Between October 1976 and January 1980 a total of 368 feral goats was examined in New Zealand for the presence of Chorioptes bovis and 434 for the presence of Psoroptes cuniculi. The seasonal pattern of C. bovis infestation in feral goats was similar to that seen in sheep and cattle. The prevalence of infestation reached 100% in July and August (winter) and declined to 27% in February and March (summer). Fewer goats were infested with P. cuniculi and prevalence of infestation reached a maximum of 41% in July. No goats were found infested in the December and January samples. Chorioptes bovis infestation was independent of the age and sex of hosts. Infestation with P. cuniculi was independent of the sex of the hosts, but older goats were more frequently infested (16%) than younger goats (8.6%). Unilateral infestation with P. cuniculi was more common (74.5%) than bilateral infestation. No severe lesions were associated with C. bovis, but 21.3% of goats with P. cuniculi had the external auditory meatus blocked by waxy material and 12.8% had scabby encrustations on the ears. The importance of goats as a possible source of infestation to domestic animals is discussed.

Goats and sheep were pastured together and held in close contact in yards twice a month for 21 months. The goats had a high prevalence of both the rabbit ear canker mite, Psoroptes cuniculi and the chorioptic mange mite, Chorioptes bovis. The sheep were not infested with P. cuniculi at the beginning of the study and viable C. bovis could not be detected. At no time during the study did P. cuniculi establish in the ears of sheep, despite a maximum prevalence of >95% P. cuniculi in goats. This may have been related to the viscous nature of sheep cerumen. Levels of cerumen in goats' ears increased with increasing prevalence of the mite in the flock. The prevalence of C. bovis in the sheep flock did not exceed 10%, despite a maximum prevalence of >90% infested goats. The difficulty of detecting light infestations of mites means that it was not clear whether the C. bovis infestation of sheep was derived from goats or was present when the study began. Whatever the source, close contact with goats with an active and extensive C. bovis infestation seems unlikely to seriously influence populations of the ectoparasite in sheep. Psoroptes cuniculi was found to he established in goats as young as five days and post-mortem examination of goats' ears was more successful at revealing P. cuniculi than was use of an otoscope during life.