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High-resolution mapping of tropical forest carbon stocks can assist forest management and improve implementation of large-scale carbon retention and enhancement programs. Previous high-resolution approaches have relied on field plot and/or light detection and ranging (LiDAR) samples of aboveground carbon density, which are typically upscaled to larger geographic areas using stratification maps. Such efforts often rely on detailed vegetation maps to stratify the region for sampling, but existing tropical forest maps are often too coarse and field plots too sparse for highresolution carbon assessments. We developed a top-down approach for high-resolution carbon mapping in a 16.5 million ha region (> 40%) of the Colombian Amazon - a remote landscape seldom documented. We report on three advances for large-scale carbon mapping: (i) employing a universal approach to airborne LiDAR-calibration with limited field data; (ii) quantifying environmental controls over carbon densities; and (iii) developing stratification- and regression-based approaches for scaling up to regions outside of LiDAR coverage. We found that carbon stocks are predicted by a combination of satellite-derived elevation, fractional canopy cover and terrain ruggedness, allowing upscaling of the LiDAR samples to the full 16.5 million ha region. LiDAR-derived carbon maps have 14% uncertainty at 1 ha resolution, and the regional map based on stratification has 28% uncertainty in any given hectare. High-resolution approaches with quantifiable pixel-scale uncertainties will provide the most confidence for monitoring changes in tropical forest carbon stocks. Improved confidence will allow resource managers and decision makers to more rapidly and effectively implement actions that better conserve and utilize forests in tropical regions. [ABSTRACT FROM AUTHOR]

High-resolution mapping of tropical forest carbon stocks can assist forest management and improve implementation of large-scale carbon retention and enhancement programs. Previous high-resolution approaches have relied on field plot and/or Light Detection and Ranging (LiDAR) samples of aboveground carbon density, which are typically upscaled to larger geographic areas using stratification maps. Such efforts often rely on detailed vegetation maps to stratify the region for sampling, but existing tropical forest maps are often too coarse and field plots too sparse for high resolution carbon assessments. We developed a top-down approach for high-resolution carbon mapping in a 16.5 million ha region (>40 %) of the Colombian Amazon -- a remote landscape seldom documented. We report on three advances for large-scale carbon mapping: (I) employing a universal approach to airborne LiDAR-calibration with limited field data; (ii) quantifying environmental controls over carbon densities; and (iii) developing stratification- and regression-based approaches for scaling up to regions outside of LiDAR coverage. We found that carbon stocks are predicted by a combination of satellite-derived elevation, fractional canopy cover and terrain ruggedness, allowing upscaling of the LiDAR samples to the full 16.5 million ha region. LiDAR-derived carbon mapping samples had 14.6% uncertainty at 1 ha resolution, and regional maps based on stratification and regression approaches had 25.6% and 29.6% uncertainty, respectively, in any given hectare. High-resolution approaches with reported local-scale uncertainties will provide the most confidence for monitoring changes in tropical forest carbon stocks. Improved confidence will allow resource managers and decisionmakers to more rapidly and effectively implement actions that better conserve and utilize forests in tropical regions. [ABSTRACT FROM AUTHOR]

AbstractObjective:To evaluate the role of vestibular assessment in the management of the dizzy patient.Materials and methods:A retrospective review of case notes and vestibular assessment reports of 100 consecutive patients referred for vestibular assessment.Results:Sixty of the 100 patients had an abnormal vestibular assessment. Eleven patients had benign paroxysmal positional vertigo as the sole diagnosis, of whom nine had not had a Dix?Hallpike manoeuvre performed before referral. Of patients referred for vestibular rehabilitation, 76 per cent had an abnormal electrophysiological assessment. After vestibular assessment, 35 patients were discharged with no further follow-up appointments in the ENT department.Conclusions:All patients should have a Dix?Hallpike manoeuvre performed prior to referral for vestibular assessment. The majority of our patients undergoing vestibular rehabilitation had abnormal test results, although a significant number did not. Prior to referral, it is worth considering the implication of a ?normal? and ?abnormal? result for the management of the patient. Careful consideration should be given to the development of dedicated dizziness clinics run by practitioners with a specialist interest in balance disorders, in order to ensure appropriate requests for vestibular assessment. [ABSTRACT FROM AUTHOR]

Sheep and cattle are frequently subjected to feed and water deprivation (FWD) for about 12?h before, and then during, transport to reduce digesta load in the gastrointestinal tract. This FWD is marked by weight loss as urine and faeces mainly in the first 24?h but continuing at a reduced rate subsequently. The weight of rumen contents falls although water loss is to some extent masked by saliva inflow. FWD is associated with some stress, particularly when transportation is added. This is indicated by increased levels of plasma cortisol that may be partly responsible for an observed increase in the output of water and N in urine and faeces. Loss of body water induces dehydration that may induce feelings of thirst by effects on the hypothalamus structures through the renin?angiotensin?aldosterone system. There are suggestions that elevated cortisol levels depress angiotensin activity and prevent sensations of thirst in dehydrated animals, but further research in this area is needed. Dehydration coupled with the discharge of Na in urine challenges the maintenance of homeostasis. In FWD, Na excretion in urine is reduced and, with the reduction in digesta load, Na is gradually returned from the digestive tract to the extracellular fluid space. Control of enteropathogenic bacteria by normal rumen microbes is weakened by FWD and resulting infections may threaten animal health and meat safety. Recovery time is required after transport to restore full feed intake and to ensure that adequate glycogen is present in muscle pre-slaughter to maintain meat quality. [ABSTRACT FROM AUTHOR]

Interfacing of ferroelectric and semiconductor materials provides a means of coupling unique properties associated with ferroelectric materials to high performance semiconductor devices. In this work we report the electronic properties of ferroelectric/ZnO heterostructures, where (Pb,Zr)TiO3(PZT) is used as a prototypical ferroelectric oxide. Metal-PZT-metal structures demonstrate ferroelectric hysteresis with remanent polarization of 28?µC?cm?2and coercive field of 75?kV?cm?1for a loop of 15?V. The metal-PZT-ZnO capacitor structures demonstrate a characteristic metal-insulator-semiconductor capacitance-voltage (C-V) behaviour with a hysteretic memory window of approximately 4?V. The heterostructure C-Vcharacteristics do not change significantly with varying frequency. Metal-PZT-ZnO capacitors are also used as part of a simple RLC circuit to demonstrate the ability to shift resonant frequency of the circuit with switching ferroelectric polarization. [ABSTRACT FROM AUTHOR]

Surveys of spiny lobster (Panulirus cygnus) populations in shallow waters surrounding Rottnest Island in Western Australia revealed much higher levels of density, biomass and egg production in no-take than in fished areas. Density of lobsters was ~34 times higher in the sanctuary, and density of lobsters above minimum legal size around 50 times higher than in other areas around the island where recreational fishing is allowed. Mean carapace length (CL), total biomass and egg production of lobsters in the sanctuary zone were significantly higher than in adjacent fished areas. Large individuals (?100 mm CL), especially large males, were found almost exclusively within the sanctuary. The abundance of mature animals in these shallow waters indicates that not all P. cygnus migrate to deep water and that shallow water habitats may currently be well below carrying capacity in terms of biomass and egg production. If implemented in a systematic way, unfished areas such as the Kingston Reefs could also provide a useful fisheries-independent tool for assessing trophic interactions and the structure and density of unfished populations, and for estimating parameters such as growth of larger individuals that may be rare or absent in more widely fished populations. [ABSTRACT FROM AUTHOR]

Chronic idiopathic subjective tinnitus is a common condition affecting around one in ten of the population at any given time. For the majority of people it is an annoyance rather than a major health issue but for approximately 0.5 per cent of the population tinnitus interferes with their ability to pursue a normal life. Modern theories of the pathogenesis of the condition concentrate on the central auditory system although the peripheral auditory system can be a trigger or ignition site for tinnitus. Although a cure remains elusive there are several good treatment strategies based on psychological and neurophysiological models of tinnitus that promote habituation to the symptom. [ABSTRACT FROM AUTHOR]

Photoconductivity is observed in ZnO epilayers due to photoexcitation in the visible spectral region of 400–700 nm, below the ZnO bandgap energy of 3.4 eV. Photoconductive transients due to visible photoexcitation have time constants in the order of minutes. Treatment of the ZnO surface with SiO2 passivation layers results in a significant reduction in the photoconductive signal and photoconductive time constant. The photoconductive response is attributed to hole traps in ZnO, where a rate equation model is presented to describe the photoconductive characteristics. A method of extracting the hole trap density spectrum is presented on the basis of the rate equation model and assumptions for hole capture lifetime and carrier recombination lifetime that are validated by experimental time-resolved photoluminescence measurements of the material under study. Traps are found to be distributed near 0.75 eV and 0.9 eV from the valence band edge for SiO2 passivated and unpassivated ZnO epilayers, respectively. [ABSTRACT FROM AUTHOR]

An A-loop is a loop in which every inner mapping is an automorphism. A problem which had been open since 1956 is settled by showing that every diassociative A-loop is Moufang. [ABSTRACT FROM AUTHOR]

A split-plot experiment was conducted in southern Chile to study the effects of tree cover and level of fertilizer application at establishment on the morphology and development of the legumes Lotus uliginosus and Trifolium subterraneum, when sown in conjunction with Festuca arundinacea as the companion grass. Trees were 13-year-old Pinus radiata, spaced at 4 × 12.5 m intervals and with a mean canopy diameter of 4.8 m. At 150 days after sowing the total area of Lotus leaves and length of Lotus stems/plant were not affected by tree cover. Individual plants had fewer stems but they were longer. For Trifolium, despite large increases in individual petiole length and leaf area, total petiole length and leaf area/plant were reduced by tree cover because of a reduced number of petioles/plant. At 275 days after sowing, the number and weight of Lotus components/ha was not affected by tree cover, although companion grass development was reduced. By 640 days the number and weight of Lotus components/ha was reduced but only to the same degree as the companion grass. Trifolium plant development, and in particular seed yield, was affected by tree cover at 275 and 640 days and to a greater extent than Lotus or the companion grass. A high level of fertilizer application at establishment induced a greater development of both legumes at 275 days, but by 640 days the effects were much reduced. It is concluded that both Lotus uliginosus and Trifolium subterraneum respond to tree cover by increasing stem length and leaf area, but that in situations with low soil fertility, the development of Lotus is less affected by tree cover than Trifolium. [ABSTRACT FROM AUTHOR]

An experiment was conducted in southern Chile to study the effect of tree cover (0 or 200 stems of 13-year-old Pinus radiata/ha), grazing severity (8 or 12 cm height at commencement of grazing by sheep) and fertilizer application rate (low or high) on the establishment and growth of Lotus uliginosus and Trifolium subterraneum, when sown in conjunction with Festuca arundinacea. The establishment of both legumes was greater in the agroforestry than the open field, and the percentage of viable seeds that were established was greater for Trifolium than Lotus. Festuca established better when sown in conjunction with Lotus in the open field. During the two years after stand establishment there was a greater reduction in the ground cover and dry matter (DM) yield of both legumes, but in particular Trifolium, in the agroforestry than in the open field. In the second year of grazing Trifolium contributed less than 9% of total DM yield in the agroforestry, compared with 22% for Lotus. The ground cover of Lotus was increased by a tall grazing height in the agroforestry, whereas Trifolium increased its cover when the grazing height was short. Additional fertilizer at establishment had a greater effect in increasing herbage yield in the open field than in agroforestry. It is concluded that both Lotus and Trifolium establishments are greater in agroforestry than in an open field, but that in agroforestry there is a reduction in legume yield over time, particularly of Trifolium. [ABSTRACT FROM AUTHOR]

The yield of Sc3N@C80 metallofullerene and fullerene extract is dramatically increased via filling cored graphite rods with copper and Sc2O3 only; when compared to 100% Sc2O3 packed rods, improvements of factors of ∼3 and ∼5 have been achieved for Sc3N@C80 and fullerene extract produced, respectively, with the weight percent of Cu added to the rod affecting the type and amount of fullerene produced. [ABSTRACT FROM AUTHOR]

Basal cell adenocarcinoma is a rare and relatively recently characterised malignant salivary gland tumour. It accounts for 5 per cent of parotid gland tumours and 1 per cent of salivary gland malignancies. It is very rarely documented in anatomical sites other than the major salivary glands. Basal cell adenocarcinoma has only been described once before in the ethmoid sinus.We report a case of basal cell adenocarcinoma in the ethmoid sinus, extending into the right orbit and anterior cranial fossa. We describe the clinical aspects of the patient's management and detail the histopathological features of this very rare diagnosis. [ABSTRACT FROM AUTHOR]

We present the case of a 71-year-old man with anaplastic thyroid cancer. On presentation, his thyroid function was normal, but he subsequently developed sudden, rapid thyrotoxicosis. Thyrotoxicosis in anaplastic thyroid carcinoma is very rare, but in all previously reported cases the patient was thyrotoxic at presentation. Our case is unusual as our patient presented euthyroid, and thyrotoxicosis developed subsequently. We challenge current ideas regarding the biochemical pathophysiology of rapid thyrotoxicosis in anaplastic thyroid carcinoma and provide an alternative explanation. [ABSTRACT FROM AUTHOR]

Colonic carcinoma metastasis to the thyroid is rare. Here the authors present the case of an 81-year-old lady who presented with metastatic colonic adenocarcinoma in her thyroid gland. This case is unique as it is the first to demonstrate metastasis from the colon to the thyroid with no other site involvement. The use of cytokeratin immunohistochemical staining is reviewed along with the current perspectives on the concept of skip metastasis. [ABSTRACT FROM AUTHOR]

In this note we show that the commutant of a Bol loop of odd order is a subloop. [ABSTRACT FROM AUTHOR]

X-ray lines of helium-like calcium (Ca xix) between 3.17 and 3.21 Å and associated Ca xviii dielectronic satellites have previously been observed in solar flare spectra, and their excitation mechanisms are well established. Dielectronic satellites of lower-ionization stages (Ca xvii–Ca xv) are not as well characterized. Several spectra during a large solar flare in 2001 by the DIOGENESS X-ray spectrometer on the CORONAS-F spacecraft show the Ca xvii and Ca xvi satellites, as well as lines of ionized argon (Ar xvii, Ar xvi), including dielectronic satellites. The DIOGENESS spectra are compared with spectra from a synthesis code developed here based on an isothermal assumption with various atomic sources including dielectronic satellite data from the Cowan Hartree–Fock code. Best-fit comparisons are made by varying the temperature as the code’s input (Ar/Ca abundance ratio fixed at 0.33); close agreement is achieved, although with adjustments to some ion fractions. The derived temperature is close to that derived from the two GOES X-ray channels, TGOES. Some lines are identified for the first time. Similar spectra from the P78-1 spacecraft and the Alcator C-Mod tokamak have also been analyzed and similar agreements were obtained. The importance of blends of calcium and argon lines is emphasized, affecting line ratios used for temperature diagnostics. This analysis will be applied to the Solar Maximum Mission Bent Crystal Spectrometer archive and to X-ray spectra expected from the ChemiX instrument on the Sun-orbiting Interhelioprobe spacecraft, while the relevance to X-ray spectra from non-solar sources is indicated. [ABSTRACT FROM AUTHOR]

This case report presents profound unremitting hearing loss in a 76-year-old man after having a bilateral knee replacement. There have been no other cases of permanent post-operative deafness after joint replacement in the world literature. Sudden post-operative deafness is rare. We conclude that this man's deafness is due to a fat embolism in his auditory circulation. [ABSTRACT FROM AUTHOR]

Recent work by Bulbul et al. and Boyarsky et al. has suggested that a line feature at ∼3.5 keV in the X-ray spectra of galaxy clusters and individual galaxies seen with XMM-Newton is due to the decay of sterile neutrinos, a dark matter candidate. This identification has been criticized by Jeltema & Profumo on the grounds that model spectra suggest that atomic transitions in helium-like potassium (K xviii) and chlorine (Cl xvi) are more likely to be the emitters. Here it is pointed out that the K xviii lines have been observed in numerous solar flare spectra at high spectral resolution with the RESIK crystal spectrometer and also appear in Chandra HETG spectra of the coronally active star σ Gem. In addition, the solar flare spectra at least indicate a mean coronal potassium abundance, which is a factor between 9 and 11 higher than the solar photospheric abundance. This fact, together with the low statistical quality of the XMM-Newton spectra, completely account for the ∼3.5 keV feature and there is therefore no need to invoke a sterile neutrino interpretation of the observed line feature at ∼3.5 keV. [ABSTRACT FROM AUTHOR]

Solar X-ray spectra from the REntgenovsky Spektrometr s Izognutymi Kristalami (RESIK) crystal spectrometer on the CORONAS-F spacecraft (spectral range 3.3–6.1 Å) are analyzed for 33 flares using a method to derive abundances of Si, S, Ar, and K, emission lines of which feature prominently in the spectra. For each spectrum, the method first optimizes element abundances and then derives the differential emission measure as a function of temperature based on a procedure given by Sylwester et al. and Withbroe. This contrasts with our previous analyses of RESIK spectra in which an isothermal assumption was used. The revised abundances (on a logarithmic scale with ) averaged for all the flares in the analysis are (previously 7.89 ± 0.13), (7.16 ± 0.17), (6.45 ± 0.07), and (5.86 ± 0.20), with little evidence for time variations of abundances within the evolution of each flare. Our previous estimates of the Ar and K flare abundances are thus confirmed by this analysis, but those for Si and S are reduced. This suggests that the flare abundances of Si and Ar are very close to the photospheric abundance or solar proxies, while S is significantly less than photospheric and the K abundance is much higher than photospheric. These estimates differ to some extent from those in which a single enhancement factor applies to elements with first ionization potential less than 10 eV. [ABSTRACT FROM AUTHOR]

X-ray spectra in the range 1.5–8.5 keV have been analyzed for 526 large flares detected with the Solar Assembly for X-rays (SAX) on the Mercury MESSENGER spacecraft between 2007 and 2013. For each flare, the temperature and emission measure of the emitting plasma were determined from the spectrum of the continuum. In addition, with the SAX energy resolution of 0.6 keV (FWHM) at 6 keV, the intensities of the clearly resolved Fe-line complex at 6.7 keV and the Ca-line complex at 3.9 keV were determined, along with those of unresolved line complexes from S, Si, and Ar at lower energies. Comparisons of these line intensities with theoretical spectra allow the abundances of these elements relative to hydrogen to be derived, with uncertainties due to instrument calibration and the unknown temperature distribution of the emitting plasma. While significant deviations are found for the abundances of Fe and Ca from flare to flare, the abundances averaged over all flares are found to be enhanced over photospheric values by factors of 1.66 ± 0.34 (Fe), 3.89 ± 0.76 (Ca), 1.23 ± 0.45 (S), 1.64 ± 0.66 (Si), and 2.48 ± 0.90 (Ar). These factors differ from previous reported values for Fe and Si at least. They suggest a more complex relation of abundance enhancement with the first ionization potential (FIP) of the element than previously considered, with the possibility that fractionation occurs in flares for elements with an FIP of less than ∼7 eV rather than ∼10 eV. [ABSTRACT FROM AUTHOR]

In order to further understand the contribution of venous and arterial effects to the photoplethysmographic (PPG) signal, recordings were made from 20 healthy volunteer subjects during an exercise in which the right hand was raised and lowered with reference to heart level. Red (R) and infrared (IR) PPG signals were obtained from the right index finger using a custom-made PPG processing system. Laser Doppler flowmetry (LDF) signals were also recorded from an adjacent fingertip. The signals were compared with simultaneous PPG signals obtained from the left index finger. On lowering the hand to 50 cm below heart level, both ac and dc PPG amplitudes from the finger decreased (e.g. 18.70 and 63.15% decrease in infrared dc and ac signals respectively). The decrease in dc amplitude most likely corresponded to increased venous volume, while the decrease in ac PPG amplitude was due to regulatory adjustments on the arterial side in response to venous distension. Conversely, ac and dc PPG amplitudes increased on raising the arm above heart level. Morphological changes in the ac PPG signal are thought to be due to vascular resistance changes, predominately venous, as the hand position is changed. [ABSTRACT FROM AUTHOR]

An abstract of the article "Rapid Bedside Consultation in the Pediatric Setting: From Conception to Implementation," by P. Schriver, J. Vaupel-Phillips, J. Cappon, P. Huddleson and N. Ryan is presented.

Objectives: To compare the noise and vibration levels associated with three hand-held rock drills (pneumatic, hydraulic and electric) currently used in South African mines, and a prototype acoustically shielded self-propelled rock drill. Methods: Equivalent A-weighted sound pressure levels were recorded on a geometrical grid, using Rion NL-11 and NL-14 sound level meters. Vibration measurements were conducted on the pneumatic, hydraulic and electric drills in accordance with the ISO5349-1 (2001) international standard on human exposure to hand-transmitted vibration, using a Brϋel and Kjær UA0894 hand adaptor. PCB Piezo accelerometers were used to measure vibration in three orthogonal directions. No vibration measurements were conducted on the self-propelled drill. Results: All four drills emitted noise exceeding 85 dB(A). The pneumatic drill reached levels of up to 114 dB(A), while the shielded self-propelled drill almost complied with the 85 dB(A) 8 h exposure limit. Vibration levels of up to 31 m s−2 were recorded. These levels greatly exceed recommended and legislated levels. Conclusions: Significant engineering advances will need to be made in the manufacture of rock drills to impact on noise induced hearing loss and hand arm vibration syndrome. Isolating the operator from the drill, as for the self-propelled drill, addresses the problems of both vibration and noise exposure, and is a possible direction for future development. [ABSTRACT FROM AUTHOR]