Summary
This study analyzed elderly women who had chest radiograph and chest CT with indications other than spine disorders. Using CT images as reference, the study demonstrates that radiograph can ...miss a high portion of mild endplate depression. Detection of endplate depression is confounded by the limitation of projectional overlay for radiograph.
Introduction
The definition of radiographic OVF (osteoporotic vertebral fracture) remains controversial. Some authors suggest all OVFs should demonstrate endplate fracture/depression on radiograph. Using CT image as the reference, our study tests the hypothesis that a considerable portion of endplate depressions not seen on radiograph can be detected on CT.
Methods
We retrospectively analyzed 46 female cases (age: 67–94 years) who had both chest radiography and chest CT with indications other than spine disorders. Sixty-six “vertebrae of interest” were identified on radiograph; then, CT images were read side-by-side with lateral chest radiograph.
Results
Thirty-eight vertebrae (38/66) had anterior wedging deformity with height loss of < 20% while without radiographic endplate depression. Among them, 28 vertebrae had endplate depression and 8 vertebrae had no endplate depression on CT, while 2 vertebrae with “very” minimal deformity were read as normal on CT. In 9 vertebrae (9/66) with anterior wedging and height loss of ≥ 20%, all had additional endplate depression seen on CT. Five vertebrae (5/66) had ambiguous endplate depression on radiograph, 3 had endplate depression on CT while the other 2 vertebrae in one patient were false positive due to X-ray projection. There were 14 short height vertebrae (14/66) where middle and anterior heights were reduced to the same extent while did not show apparent anterior wedging or bi-concaving. Four cases each had one short height vertebra, and all had endplate depression on CT. Another 4 cases had 2, 2, 3, and 3 adjacent short height vertebrae, respectively, and all did not show endplate depression on CT. In addition, inspection of spine CT showed 10 vertebrae in 9 cases appeared normal on radiograph while demonstrated endplate depression on CT.
Conclusion
With CT images as reference, radiograph can miss a high portion of mild endplate depressions.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A Nationwide Nitrogen Deposition Monitoring Network (NNDMN) containing 43 monitoring sites was established in China to measure gaseous NH3, NO2, and HNO3 and particulate NH4+ and NO3− in air and/or ...precipitation from 2010 to 2014. Wet/bulk deposition fluxes of Nr species were collected by precipitation gauge method and measured by continuous-flow analyzer; dry deposition fluxes were estimated using airborne concentration measurements and inferential models. Our observations reveal large spatial variations of atmospheric Nr concentrations and dry and wet/bulk Nr deposition. On a national basis, the annual average concentrations (1.3–47.0 μg N m−3) and dry plus wet/bulk deposition fluxes (2.9–83.3 kg N ha−1 yr−1) of inorganic Nr species are ranked by land use as urban > rural > background sites and by regions as north China > southeast China > southwest China > northeast China > northwest China > Tibetan Plateau, reflecting the impact of anthropogenic Nr emission. Average dry and wet/bulk N deposition fluxes were 20.6 ± 11.2 (mean ± standard deviation) and 19.3 ± 9.2 kg N ha−1 yr−1 across China, with reduced N deposition dominating both dry and wet/bulk deposition. Our results suggest atmospheric dry N deposition is equally important to wet/bulk N deposition at the national scale. Therefore, both deposition forms should be included when considering the impacts of N deposition on environment and ecosystem health.
Atmospheric reactive nitrogen (N
r
) has been a cause of serious environmental pollution in China. Historically, China used too little N
r
in its agriculture to feed its population. However, with the ...rapid increase in N fertilizer use for food production and fossil fuel consumption for energy supply over the last four decades, increasing gaseous N
r
species (e.g. NH
3
and NO
x
) have been emitted to the atmosphere and then deposited as wet and dry deposition, with adverse impacts on air, water and soil quality as well as plant biodiversity and human health. This paper reviews the issues associated with this in a holistic way. The emissions, deposition, impacts, actions and regulations for the mitigation of atmospheric N
r
are discussed systematically. Both NH
3
and NO
x
make major contributions to environmental pollution but especially to the formation of secondary fine particulate matter (PM
2.5
), which impacts human health and light scattering (haze). In addition, atmospheric deposition of NH
3
and NO
x
causes adverse impacts on terrestrial and aquatic ecosystems due to acidification and eutrophication. Regulations and practices introduced by China that meet the urgent need to reduce N
r
emissions are explained and resulting effects on emissions are discussed. Recommendations for improving future N management for achieving ‘win-win’ outcomes for Chinese agricultural production and food supply, and human and environmental health, are described.
This article is part of a discussion meeting issue ‘Air quality, past present and future’.
Multilocular cystic renal neoplasm of low malignant potential (MCRNLMP) might be benefited from nephron-sparing surgery. Contrast-enhanced computed tomography is used for the diagnosis of MCRNLMP but ...contrast-enhanced ultrasound has lack of nephrotoxicity and several advantages over contrast-enhanced computed tomography and contrast-enhanced magnetic resonance. The purpose of the study was to compare diagnostic parameters of preoperative contrast-enhanced ultrasound against contrast-enhanced computed tomography for the detection of MCRNLMP in patients who faced curative surgery for complex cystic renal mass.Data regarding contrast-enhanced ultrasound, contrast-enhanced computed tomography, and clinicopathological results of 219 patients who underwent curative surgery for complex cystic renal mass (Bosniak classification III or IV) were retrospectively collected and analyzed. Bosniak classification for imaging modality and the 2016 WHO criteria for clinic pathology were used for detection of MCRNLMP.Contrast-enhanced ultrasound, contrast-enhanced computed tomography, and clinicopathology were detected 68, 66, and 67 as a MCRNLMP respectively. Contrast-enhanced ultrasound and contrast-enhanced computed tomography had 30.37% and 29.27% sensitivities for the detection of MCRNLMP. While 60% and 50% specificities respectively. Bosniak classification III (P = .045) and lower mean Hounsfield unit (P = .049) were associated with the prevalence of MCRNLMP. Contrast-enhanced computed tomography was detected 6 and 7, while contrast-enhanced ultrasound detected 3 and 2 complex cystic renal mass as false positive and false negative MCRNLMP respectively. A contrast-enhanced ultrasound had 0.011 to 1.0 diagnostic confidence and contrast-enhanced computed tomography had 0.045 to 0.983 diagnostic confidence for decision making of nephron-sparing surgeries.Contrast-enhanced ultrasound may have better visualization of MCRNLMP than contrast-enhanced computed tomography.Level of Evidence: III.
Vigilance in ungulates is considered to have a predominantly antipredator function, with the frequency and duration of scans per individual decreasing with increasing group size. Social influences on ...vigilance scans have been overlooked in studies on ungulates, although studies in primates and birds show that conspecific scans are important determinants of vigilance behaviour. We investigated group size effects in giraffes and examined social influences on their scanning behaviour, as well as the influence of feeding posture. We found that group size has little effect on scanning behaviour in either bulls or cows, which may be attributable to our inability to measure a group as perceived by a giraffe. Time spent scanning by lone cows did not differ from that of cows in any other group type, but time spent scanning by bulls when alone was less than that in groups. The presence of calves in a group did not influence scanning behaviour. Predation risk does not appear to be a significant modifier of vigilance behaviour, although a constant level of antipredator vigilance is probably maintained. Social factors were a significant modifier of vigilance scanning. Bulls scanned the most when they were in groups with larger bulls, and least when they were with smaller bulls. A similar pattern was seen with nearest-neighbour identity, and the identity of individuals within 10
m of a focal animal. Cows were significantly more vigilant when an adult bull was close, or was the nearest neighbour. Finally, vigilance advantages have been postulated as a determinant of sexual segregation in giraffe foraging heights but we found that the posture associated with high foraging heights imposes a vigilance cost, not an advantage. We therefore conclude that differential vigilance requirements are not a determinant of feeding height segregation between giraffe bulls and cows.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Scat analysis is one of the most frequently used methods to assess carnivoran diets, and global positioning system (GPS) cluster methods are increasingly being used to locate feeding sites for large ...carnivorans. However, both methods have inherent biases that limit their use. GPS methods to locate kill sites are biased towards large carcasses, while scat analysis overestimates the biomass consumed from smaller prey. We combined carcass observations and scats collected along known movement routes, assessed using GPS data from four African lion Panthera leo prides in the Kruger National Park, South Africa, to determine how a combination of these two datasets change diet estimates. As expected, using carcasses alone underestimated the number of feeding events on small species, primarily impala Aepyceros melampus and warthog Phacochoerus africanus, in our case, by more than 50%, and thus significantly underestimated the biomass consumed per pride per day in comparison with when the diet was assessed using carcass observations alone. We show that an approach that supplements carcass observations with scats that enables the identification of potentially missed feeding events increases the estimates of food intake rates for large carnivorans, with possible ramifications for predator–prey interaction studies dealing with biomass intake rate.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Aims: To investigate the early pattern of longitudinal change in forced expiratory volume in 1 second (FEV1) among new Chinese coal miners, and the relation between coal mine dust exposure and the ...decline of lung function. Methods: The early pattern of lung function changes in 317 newly hired Chinese underground coal miners was compared to 132 referents. This three year prospective cohort study involved a pre-employment and 15 follow up health surveys, including a questionnaire and spirometry tests. Twice a month, total and respirable dust area sampling was done. The authors used a two stage analysis and a linear mixed effects model approach to analyse the longitudinal spirometry data, and to investigate the changes in FEV1 over time, controlling for age, height, pack years of smoking, mean respirable dust concentration, the room temperature during testing, and the group×time interaction terms. Results: FEV1 change over time in new miners is non-linear. New miners experience initial rapid FEV1 declines, primarily during the first year of mining, little change during the second year, and partial recovery during the third year. Both linear and quadratic time trends in FEV1 change are highly significant. Smoking miners lost more FEV1 than non-smokers. Referents, all age less than 20 years, showed continued lung growth, whereas the miners who were under age 20 exhibited a decline in FEV1. Conclusion: Dust and smoking affect lung function in young, newly hired Chinese coal miners. FEV1 change over the first three years of employment is non-linear. The findings have implications for both methods and interpretation of medical screening in coal mining and other dusty work: during the first several years of employment more frequent testing may be desirable, and caution is required in interpreting early FEV1 declines.
Full text
Available for:
BFBNIB, CMK, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Measurements of 81Kr/Kr in deep groundwater from the Nubian Aquifer (Egypt) were performed by a new laser‐based atom‐counting method. 81Kr ages range from ∼2 × 105 to ∼1 × 106 yr, correlate with ...36Cl/Cl ratios, and are consistent with lateral flow of groundwater from a recharge area near the Uweinat Uplift in SW Egypt. Low δ2H values of the 81Kr‐dated groundwater reveal a recurrent Atlantic moisture source during Pleistocene pluvial periods. These results indicate that the 81Kr method for dating old groundwater is robust and such measurements can now be applied to a wide range of hydrologic problems.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Freestanding nanowires have ultrahigh elastic strain limits (4 to 7%) and yield strengths, but exploiting their intrinsic mechanical properties in bulk composites has proven to be difficult. We ...exploited the intrinsic mechanical properties of nanowires in a phase-transforming matrix based on the concept of elastic and transformation strain matching. By engineering the microstructure and residual stress to couple the true elasticity of Nb nanowires with the pseudoelasticity of a NiTi shape-memory alloy, we developed an in situ composite that possesses a large quasi-linear elastic strain of over 6%, a low Young's modulus of ∼28 gigapascals, and a high yield strength of ∼1.65 gigapascals. Our elastic strain-matching approach allows the exceptional mechanical properties of nanowires to be exploited in bulk materials.
Full text
Available for:
BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
PDF
