Footwall refrigeration along a detachment fault: implications for the thermal evolution of core complexes

Oxygen isotope compositions of epidote and quartz from chloritic breccias that underlie the detachment fault in the metamorphic core complex of the Whipple Mountains yielded quartz-epidote fractionations that range from 4.1 to 6.4 per mil and increase systematically toward the fault. These fractionations give mean temperatures that decrease from approximately 432 degrees C at 50 meters below the fault to approximately 350 degrees C at 12 meters below the fault. This extreme thermal gradient of 82 degrees C over 38 meters (2160 degrees C per kilometer) is best explained by advective heat extraction by means of circulating surface-derived fluids. Models of lithospheric extension consider only conductive cooling resulting from tectonic denudation and thus require revision to include fluid-induced fault-zone refrigeration.     

Balibalosides,an Original Family of Glucosylated Sesterterpenes Produced by the Mediterranean Sponge Oscarella balibaloi

The chemical investigation of the recently described Mediterranean Homoscleromorpha sponge Oscarella balibaloi revealed an original family of five closely related glucosylated sesterterpenes 1–4, named balibalosides. Their structure elucidation was mainly inferred from NMR and HRMS data analyses. Balibalosides differ by the pattern of acetyl substitutions on the three sugar residues linked to the same aglycone sesterterpenoid core. From a biosynthetic perspective, these compounds may represent intermediates in the pathways leading to more complex sesterterpenes frequently found in Dictyoceratida, a sponge Order belonging to Demospongiae, a clade which is phylogenetically distinct from the Homoscleromorpha. While steroid and triterpenoid saponins were already well known from marine sponges, balibalosides are the first examples of glycosilated sesterterpenes.     

Muscle strain injuries of the hindlimb in eight horses: diagnostic imaging,management and outcomes

Objective To describe the clinical presentation, ultrasound findings, management and outcome in horses with muscle tear injuries of the hindlimbs. Design Retrospective case series Procedure Medical records of eight horses were reviewed and information on signalment, history, presenting complaint, physical examination findings and further diagnostic tests were recorded. Diagnosis of muscle injury was determined by the presence of abnormal ultrasound findings, compared with the contralateral limb, and, when required, nuclear scintigraphy. Follow-up information was obtained via telephone interviews with owners, trainers and referring veterinarians. Results Muscle tears causing lameness were identified in the middle gluteal (3), semitendinosus (1), semimembranosus (2) and gracilis (2) muscles. Tears were classified by ultrasound imaging as partial (6) or complete (2). The degree of lameness did not appear to be indicative of the extent of injury or of completion of healing. Long-term follow-up was available for seven horses and the outcome was favourable in six cases. Conclusions and clinical relevance Ultrasonography is useful in the diagnosis and assessment of moderate to severe muscle strain injuries. The prognosis appears to be favourable in most cases, although recurrence of injury and lameness can delay the return to athletic activity and an inferior outcome with persistent gait abnormality may occur.     

Preliminary Study in Immature Canine Oocytes Stained with Brilliant Cresyl Blue and Obtained From Bitches with Low and High Progesterone Serum Profiles

This study was conducted: (i) to observe the features and levels of blue colour impregnation in morphologically selected immature canine cumulus oocyte complexes (COCs) stained with the brilliant cresyl blue (BCB) dye, as indicators of quality, and integrity of nuclear oocyte chromatin configuration before in vitro maturation (IVM); (ii) to observe the relationship between the influence of serum progesterone (SP) concentrations from ovary donors and BCB staining of immature dog oocytes. The results showed that out of 138 canine COCs, germinal vesicle (GV) stage prevailed in BCB+ oocytes at percentages of 67.4% (60/89), which were statistically higher than those observed in BCB+/− (52.2%; 23/44) and BCB− (20%; 1/5) oocytes (p = 0.023). Oocytes BCB+ were interpreted as those having completed their growth and therefore possessing the capacity to mature and develop in vitro . Ooplasm and cumulus cells (CCs) of canine oocytes were BCB staining independent. Ooplasm blue colour staining reaction varied between grown oocytes, revealing different levels of glucose-6-phosphate dehydrogenase activity among and within oocytes. Additionally, SP profile of ovary donors was not a relevant indicator for selection of oocytes screened with the BCB stain. Similar numbers of high quality oocytes were observed to be BCB+, BCB+/− and BCB− between groups of females with SP varying from 0 to 2.5 ng/ml (n = 5), and those with SP varying from 2.6 to 16.7 ng/ml (n = 4) (p = 0.680). It may be inferred that bitches with low and high SP profiles have grown oocytes in their ovaries, as determined by the BCB absorbance in their ooplasms.     

Effects of blast on components of wheat physiology and grain yield as influenced by fungicide treatment and host resistance

Two field experiments (Exp. 1 and Exp. 2) were carried out to assess the physiological performance and grain yield of wheat cultivars BR‐18 (moderately resistant) and Guamirim (susceptible) inoculated with Pyricularia oryzae in plots treated or untreated with Ópera (fungicide 13.3% epoxiconazole + 5% pyraclostrobin). Results from regression analyses indicated that spike and leaf blast severity at 10–14 days after inoculation (dai) were associated with greater yield losses (highest negative slope) than severity at 18–22 dai. Relative to untreated Guamirim, there were 0.3% and 16% increases in Exp. 1 and 2, respectively, for untreated BR‐18 (resistance alone). For fungicide treatment alone, the mean yield of Guamirim increased by 20% and 61% in Exp. 1 and 2, respectively, relative to the untreated fungicide control, whereas for the fungicide treated BR‐18, the mean yield increased by 26% and 83% in Exp. 1 and 2, respectively. Fungicide application and cultivar resistance resulted in higher measures of leaf health and photosynthetic performance in both spikes and leaves than in the untreated susceptible reference treatment. The results from this study may be useful in future efforts to develop crop loss models and management guidelines for wheat blast.     

Alteration of photosynthetic performance and source–sink relationships in wheat plants infected by Pyricularia oryzae

Two experiments were carried out to assess the changes associated with photoassimilate production and partitioning in the source–sink relationship of flag leaves and spikes of wheat plants infected with Pyricularia oryzae, the causal agent of blast. Flag leaves and spikes were inoculated at 10 and 20 days after anthesis (daa) with a conidial suspension of P. oryzae. Analysis of chlorophyll a fluorescence using maximal photosystem II quantum efficiency (F_v?F_m), fraction of energy absorbed that is used in photochemistry (YII), quantum yield of non‐regulated energy dissipation (Y(NO)) and quantum yield of regulated energy dissipation (Y(NPQ)), showed an impairment of the photosynthetic performance in both infected flag leaves and spikes, coupled with reduced concentrations of chlorophyll a  + b and carotenoids. Compared to non‐inoculated controls, there was lower capacity for CO₂ fixation by RuBisCO in the infected flag leaves. Similarly, in the infected flag leaves and grains (obtained from infected spikes), there were lower concentrations of soluble sugars, while the hexoses‐to‐sucrose ratio increased in infected flag leaves. Compared to non‐inoculated controls, infected flag leaves showed lower sucrose phosphate synthase (SPS) activity and lower expression of the sucrose synthesis (SuSy) gene, while higher expression and activity of acid invertases also occurred. At the advanced stages of fungal infection, the concentration of starch in grains decreased but remained high for the infected flag leaves. There were reductions in ADP‐glucose pyrophosphorylase activity and the expression of ADP‐glucose pyrophosphorylase genes and a down‐regulation of β‐ and α‐amylase expression at the advanced stages of fungal infection on flag leaves and spikes. In conclusion, the effect of blast on both grain quality and yield can be associated with alterations in both production and partitioning of carbohydrates during the grain filling process.