Cluster analysis applied to the exploratory analysis of commercial spanish olive oils by means of excitation-emission fluorescence spectroscopy

Olive oil fluorescence is related to oil composition. Here it is shown that the natural clustering of different types of commercial Spanish olive oils depends on their fluorescence excitation-emission matrices (EEMs). Fifty-six commercial samples of olive oil (29 virgin olive oils, 20 pure olive oils, and 7 olive-pomace oils) were used. The clustering method was hierarchical agglomerative clustering using the Euclidean distance as a similarity measure and the average linkage. Two spectral ranges were considered (which either contained the fluorescence peak of the chlorophylls or did not), and various methods for preprocessing the fluorescence spectra were compared. The oils were clearly distinguished using the unfolded EEMs measured between lambda(ex) = 300-400 nm and lambda(em) = 400-600 nm. The optimal preprocessing was normalization of the unfolded spectra followed by column autoscaling. Also shown are the advantages of using second-order data (EEMs) instead of first-order data (a single fluorescence spectrum) for each sample.     

Natural emissions of oxidant precursors

This paper provides an overview of the sources, the estimation methodology, and the relative amounts of natural hydrocarbon and NO_x emissions. The most recent estimate of natural nonmethane hydrocarbon (NMHC) emissions for the United States is 28 Tg yr^?1. This compares with 20 Tg yr^?1 for anthropogenic NMHC sources. The southeastern and southcentral portions of the United States account for approximately 43% of the annual U.S. natural NMHC estimate. These emissions exhibit strong diurnal and seasonal dependencies related to temperature, solar radiation, and active biomass. Forests are the primary vegetative source of hydrocarbons. The major sources of natural NO_X emissions in North America are biomass burning, lightning, and microbial activity in soil. We present a comparison of hourly gridded NO_X emissions from lightning, soil, and man-made sources for the northeastern United States. We also provide results from preliminary investigations of the sensitivity of O₃ predictions from the U.S. Environmental Protection Agency's Regional Oxidant Model to natural NMHC and nitric oxide emissions.     

Factors involved in alleviating water stress by partial crop removal in pear trees

We studied the relief of water stress associated with fruit thinning in pear (Pyrus communis L.) trees during drought to determine what mechanisms, other than stomatal adjustment, were involved. Combinations of control irrigation (equal to crop water use less effective rainfall) and deficit irrigation (equal to 20% of control irrigation), fruit load (unthinned and thinned to 40 fruits per tree) and root pruning (pruned and unpruned) treatments were applied to pear (cv. 'Conference') trees during Stage II of fruit development. Daily patterns of midday stem water potential (Psi(stem)) and leaf conductance to water vapor (g(l)) of deficit-irrigated trees differed after fruit thinning. In response to fruit thinning, gl progressively declined with water stress until 30 days after fruit thinning and then leveled off, whereas the effects of decreased fruit load on Psi(stem) peaked 30-40 days after fruit thinning and then tended to decline. Soil water depletion was significantly correlated with fruit load during drought. Our results indicate that stomatal adjustment and the resulting soil water conservation were the factors determining the Psi(stem) response to fruit thinning. However, these factors could not explain differences in daily patterns between g(l) and Psi(stem) after fruit thinning. In all cases, effects of root pruning treatments on Psi(stem) in deficit-irrigated trees were transitory (Psi(stem) recovered from root pruning in less than 30 days), but the recovery of Psi(stem) after root pruning was faster in trees with low fruit loads. This behavior is compatible with the concept that the water balance (reflected by Psi(stem) values) was better in trees with low fruit loads compared with unthinned trees, perhaps because more carbon was available for root growth. Thus, a root growth component is hypothesized as a mechanism to explain the bimodal Psi(stem) response to fruit thinning during drought.     

A KCNJ10 mutation previously identified in the Russell group of terriers also occurs in Smooth-Haired Fox Terriers with hereditary ataxia and in related breeds

Background

Hereditary ataxias with similar phenotypes were reported in the Smooth-Haired Fox Terrier, the Jack Russell Terrier and the Parson Russell Terrier. However, segregation analyses showed differing inheritance modes in these breeds. Recently, molecular genetic studies on the Russell group of terriers found independent mutations in KCNJ10 and CAPN1, each associated with a specific clinical subtype of inherited ataxia. The aim of this study was to clarify whether or not Smooth-Haired Fox Terriers with hereditary ataxia and dogs of other related breeds harbor either of the same mutations. A sub goal was to update the results of KCNJ10 genotyping in Russell group terriers.

Findings

Three Smooth-Haired Fox Terriers with hereditary ataxia and two Toy Fox Terriers with a similar phenotype were all homozygous for the KCNJ10 mutation. The same mutation was also found in a heterozygous state in clinically unaffected Tenterfield Terriers (n = 5) and, in agreement with previous studies, in Jack Russell Terriers, Parson Russell Terriers, and Russell Terriers.

Conclusions

A KCNJ10 mutation, previously associated with an autosomal recessive spinocerebellar ataxia in Jack Russell Terriers, Parson Russell Terriers, and Russell Terriers segregates in at least three more breeds descended from British hunting terriers. Ataxic members of two of these breeds, the Smooth-Haired Fox Terrier and the Toy Fox Terrier, were homozygous for the mutation, strengthening the likelihood that this genetic defect is indeed the causative mutation for the disease known as “hereditary ataxia” in Fox Terriers and “spinocerebellar ataxia with myokymia, seizures or both” in the Russell group of terriers.     

Fecal steroid analysis for evaluating ovarian function in the greater kudu (Tragelaphus strepsiceros) and lesser kudu (Tragelaphus imberbis)

Seasonal reproductive-endocrine norms have not been described for the genus Tragelaphus, which consists of seven species of African antelope. Longitudinal patterns of progesterone metabolite excretion were assessed by radioimmunoassays in fecal samples collected noninvasively (three to seven samples per week) from greater kudu (Tragelaphus strepsiceros, n = 4) and lesser kudu (Tragelaphus imberbis, n = 4). Progesterone metabolite excretion patterns revealed seasonal estrous cycles in both species, and discrimination of pregnant versus nonpregnant females was achieved in lesser kudu. These data reveal the value of fecal progesterone metabolites for establishing reproductive-endocrine norms in both zoo-maintained and free-living antelopes of the genus Tragelaphus.     

The distribution of volatile isoprenoids in the soil horizons around Pinus halepensis trees

We measured the terpene concentration in pentane and water extracts from soil horizons (litter, organic, top and low mineral) and from roots growing in top and low mineral horizons on a distance gradient from Pinus halepensis L. trees growing alone on a grassland. Terpene concentrations in pentane were higher than in water extracts, although β-caryophyllene showed relatively high solubility in water. The litter and roots were important sources of terpenes in soil. Alpha-pinene dominated in roots growing in both “top” (A1) and “low” (B) mineral horizons (123 ± 36 μg g⁻¹ or 14 ± 5 mg m⁻²) and roots in low mineral horizon (270 ± 91 μg g⁻¹ or 7 ± 2 mg m⁻²). Beta-caryophyllene dominated in litter (1469 ± 331 μg g⁻¹ or 2004 ± 481 mg m⁻²). Terpene concentration in soil decreased with increasing distance to the trunk. This is likely to be related to changes in litter and roots type on the distance gradient from pine to grass and herbs. The relative contributions of all compounds, except α-pinene, were similar in the mineral soils and litter. This suggests that litter of P. halepensis is probably the main source of major terpene compounds. However, long-term emissions of α-pinene from P. halepensis roots might also contribute to α-pinene concentrations in rhizosphere soils.     

CAUDAL VENOUS RETURN THROUGH A LEFT AZYGOS VEIN IN A DOG

The Clinical, radiologic and echocardiographic findings in a one-year old dog with mild subvalvular aortic stenosis and aberrant caudal vena circulation are described. Aberrant systemic venous return to the right side of the heart usually has little clinical significance, but the unusual features in survey radiographs, contrast angiograms and contrast echocardiograms constitute the reasons for this report.     

COLOR DOPPLER AND DOPPLER SPECTRAL ANALYSIS IN THE SPINAL CORD OF NORMAL DOGS

Doppler ultrasonography of the spinal cord was performed in 34 normal, anesthetized dogs following hemilaminectomy. This study was part of an investigation to evaluate the efficacy of a 21-aminosteroid compound and high dose methylprednisolone for the treatment of spinal cord trauma. Grey-scale images of the canine spinal cord were similar to those described for the spinal cord of people. Doppler waveforms of intraparenchymal spinal arteries exhibited high end diastolic blood flow velocities, indicating low resistance to flow. Doppler values (mean ± SD) for arteries immediately ventrolateral to the central canal were: Peak Systolic Velocity = 5.78 ± 2.5 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Systolic/Diastolic ratio = 169 ± 0.19, Pulsatility Index = 0.53 ± 0.09, and Resistance Index = 0.4 ± 0.06.     

Myasthenia gravis and hypothyroidism in a dog with meningomyelitis

A 12-year-old, spayed female miniature poodle was evaluated because of a 4-day history of paraparesis, dysuria, and tenesmus. Neurological assessment suggested peripheral nervous system dysfunction, predominantly pelvic limb weakness with a possible concurrent sixth lumbar (L(6)) to second sacral (S(2)) myelopathy. Further studies supported the diagnoses of myasthenia gravis, hypothyroidism, and meningomyelitis. To the authors' knowledge, this is the first reported case of concurrent myasthenia gravis and meningomyelitis in the dog. It was unclear whether the identified conditions evolved from a shared etiopathogenesis or were merely coincidental.