The evolution of the modern avian digestive system: insights from paravian fossils from the Yanliao and Jehol biotas

The avian digestive system, like other aspects of avian biology, is highly modified relative to other reptiles. Together these modifications have imparted the great success of Neornithes, the most diverse clade of amniotes alive today. It is important to understand when and how aspects of the modern avian digestive system evolved among neornithine ancestors in order to elucidate the evolutionary success of this important clade and to understand the biology of stem birds and their closest dinosaurian relatives: Mesozoic Paraves. Although direct preservation of the soft tissue of the digestive system has not yet been reported, ingested remains and their anatomical location preserved in articulated fossils hint at the structure of the digestive system and its abilities. Almost all data concerning direct evidence of diet in Paraves comes from either the Upper Jurassic Yanliao Biota or the Lower Cretaceous Jehol Biota, both of which are known from deposits in north-eastern China. Here, the sum of the data gleaned from the thousands of exceptionally well-preserved fossils of paravians is interpreted with regards to the structure and evolution of the highly modified avian digestive system and feeding apparatus. This information suggests intrinsic differences between closely related stem lineages implying either strong homoplasy or that diet in each lineage of non-ornithuromorph birds was highly specialized. Regardless, modern digestive capabilities appear to be limited to the Ornithuromorpha, although the complete set of derived feeding related characters is restricted to the Neornithes.     

Effect of Preparation Methods on Mechanical Properties of PVA/HA Composite Hydrogel

##正## Poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) composite hydrogel specimens were prepared with 15% PVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel. The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation properties, higher relaxation ratio, lower stress equilibrium value andpresented better properties of creep and recovery. The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the PVA/HA compositehydrogel with 3% HA.     

Mineral and trace element research in goats: A review

The long term studies with dairy goats on the effects of deficient semisynthetic feeding rations in one of 16 elements as reported in the annual proceedings of the Workshops on Minerals and Trace Elements and the International Trace Element Symposia by the University of Jena, Germany, since 1975 until today were reviewed. The development of the complex semisynthetic ration system was particularly important as it enabled to produce significant deficiencies of single elements in long term replicated studies and their interactions with other elements. The studies focused mainly on determining deficiency levels for each of the 16 elements, identifying deficiency symptoms and reasons for them, and establishing evidence for essentiality of the elements according to 7 criteria. Large amounts of analytical data were accumulated showing the changes in organ and tissue contents of the elements under study at normal and deficient levels, and their relation to impaired reproductive efficiency, growth, milk production, health, and mortality of goats and their kids. Histological sections of organs also showed their ultrastructural changes due to the elemental deficiencies. Most element deficiencies caused reproductive failures, reduced growth and milk production, but high mortality, while the control goats thrived on their semisynthetic but sufficient ration, attesting to its completely correct biological value. The identification of the reliable “indicator” organs and tissues for the diagnosis and detection of deficiency status of the specific elements in goats is of particular value to veterinary medicine and animal nutrition.     

The role of chromium and nickel on the thermal and mechanical properties of FeNiCr austenitic stainless steels under high pressure and temperature: a molecular dynamics study

The effect of Cr and Ni content on thermo-mechanical properties of FeNiCr austenitic stainless steel under ambient and high pressure and temperature were investigated by MD simulations. The FCC structure was selected as optimum structure for FeNiCr system based on obtained MD results from Bonny EAM potential and valid experimental results. The structural and mechanical properties of pure Fe, Ni, and Cr were also estimated based on this potential, indicating good agreement with experimental results. These properties were computed for four experimental case studies which showed less than 10% error. Moreover, the elastic constants of the Fe–(8–18)Ni–(18–25)Cr systems were estimated. Results showed that bulk modulus increases by increasing the Ni and Cr contents, which can be connected to the changes in bonding electrons. The thermal properties of FeNiCr were calculated in ambient and high pressure. Although thermo-mechanical properties confirm good agreement with experimental results at the ambient condition, however, they indicate that FeNiCr Bonny potential is not applicable at high pressure. In order to tackle this issue, a hybrid potential was used at high Pressure/Temperature. The results illustrate enhanced mechanical properties, increase of melting point and reduction of LTE in high pressure and deteriorated mechanical properties at high temperature.     

The effect of insulin and glucose on fructose-2,6-P2 in hepatocytes

When rats were kept on a riboflavin-deficient diet, NADPH-cytochrome c and NADPH-ferricyanide reductase activities of the liver microsomes (deficient microsomes) decreased to 27% and 40% of the corresponding controls. To elucidate the unbalanced decrease of these activities in deficient microsomes, enzymological and immunochemical properties of the NADPH-cytochrome P-450 reductase in the liver microsomes of riboflavin-deficient rats were compared with those of control rats. Judging from quantitative immunoprecipitation, the amount of the reductase protein in the deficient microsomes was 67% of control, whereas the FAD and FMN contents in the immunoprecipitates were 110% and 59% of control, respectively. When the reductase was purified from the deficient microsomes, it contained 18.0 and 10.9 nmoles of FAD and FMN, respectively, per mg of protein, while the control enzyme contained 14.5 and 14.3 nmoles of the flavins, respectively. These and other lines of evidence suggest the existence of an abnormal NADPH-cytochrome P-450 reductase, having unbalanced contents of FAD and FMN, in deficient microsomes.     

First Report about Mineral Content,Fatty Acids Composition and Biological Activities of Four Wild Edible Mushrooms

The goal of this research was a comprehensive analysis of four wild edible mushroom species, Cantharellus cinereus, Clavariadelphus pistillaris, Clitocybe nebularis and Hygrocybe punicea, which have not been analyzed so far. Extracts of different polarities have been prepared and evaluated for their antioxidant activities by DPPH, ABTS, FRAP, TRP and CUPRAC methods. For all extracts, total phenolic content was determined. Based on the analysis, it was shown that solvent type had a significant effect on the antioxidant capacities of mushroom extracts, so water extracts showed the highest activity. Furthermore, the analysis includes determination of mineral composition, fatty acid profiles and antimicrobial activity. Unsaturated fatty acids, which are very important for human health, are dominant in the studied mushroom species. Linoleic and oleic acid consist of over 50 % of the total fatty acid composition. Seventeen biologically important and toxic elements have been analyzed by ICP‐OES and ICP‐MS and results showed that the element concentrations were species‐dependent. Also, it has been found that analyzed mushrooms did not show any antimicrobial activity. Chemometric analysis was used to understand the connection between the extracts of different polarities.     

Integrated Use of Organic and Bio-fertilizers to Improve Yield and Fruit Quality of Olives Grown in Low Fertility Sandy Soil in an Arid Environment

Olive productivity should be improved through stimulating nutrition, particularly under poor fertility soils. Consequently, the objective of this study was to assess the efficacy of applying organic and bio-fertilizers on the physiological growth, yield and fruit quality of olive trees under newly reclaimed poor-fertility sandy soil in an arid environment. During a field experiment carried out at El-Qantara, North Sinai, Egypt over two consecutive seasons (2019–2020 and 2020–2021), olive Kalamata trees were evaluated under three organic fertilizer treatments alone or in combination with three bio-fertilizers treatments. Organic fertilizer was applied as goat manure (16.8 kg/tree/year), or olive pomace (8.5 kg/tree/year) in mid-December of each season vs. untreated trees. The bio-fertilizers were applied as N-fixing bacteria (150 g/tree) was inculated in early March of each season, or amino acid mixture (1.5%) was applied three times, at 70% of full bloom, 21 days after full bloom, and a month later in comparison to a non-fertilized trees (control). The cultivar used was Kalamata, a dual-purpose cultivar for oil and table olives whose value increases when processed as table olives. The results indicated that the goat manure followed by olive pomace significantly enhanced photosynthetic pigments (chlorophyll a, b, and carotenoids), leaf mineral contents (N, P, K, Ca, Mg and Fe), tree canopy volume, number of flowers per inflorescence, number of inflorescences per shoot, initial fruit set, fruit retention. For fruit quality, fruit length and width, fruit weight, and total fruit yield was increased compared to the non-fertilized control. Likewise, The bio-fertilizer N-fixing bacteria followed by the amino acid mixture significantly improved all of the aforementioned parameters. Accordingly, it is recommended, both environmentally and economically to utilize organic and bio-fertizers, particularly goat manure combined with N-fixing bacteria, in low-fertility soil to sustain olive production as well as reducing mineral fertilization.     

Water and electrolyte balance in protoscoleces of Echinococcus granulosus incubated in vitro: Effect of metabolic inhibitors

Reisin I.L., Rabito C.A. and Cantiello H.F. 1981. Water and electrolyte balance in protoscoleces of Echinococcus granulosus incubated in vitro: effect of metabolic inhibitors. International Journal for Parasitology 11: 405–410. The effects of metabolic inhibitors on the Na⁺, K⁺, Cl^? and water balance of protoscoleces of Echinococcus granulosus (sheep strain) were studied in vitro. The protoscoleces were incubated at 37°C in Ringer Krebs solution for 3 h in the presence of iodoacetate, 3 mM (IA); potassium cyanide, 3 mm (KCN); 2?4 dinitrophenol, 0.2 mm (DNP); ouabain, 10^?M or ethacrynic acid 0.5 mm. The effects of IA and/or KCN on the water and electrolyte balance were tested at high (0.95 × 10⁵Pa) and low (0.05 × 10⁵ Pa) oxygen tensions. Inhibitors produced a decrease in K⁺ as well as an increase in Na⁺ contents. At both high and low O₂ tensions the Na⁺ balance was greatly altered by IA, the action of which could be already observed during the first hour of treatment. The cations did not reach a steady state balance during 3 h of incubation. At high oxygen tension Na⁺ and K⁺ balance was also altered by KCN or DNP though their actions were not as marked as that of IA. Ouabain affected the Na⁺ and K⁺ contents that reached new steady state distribution between 1.5 and 3 h of treatment while water and electrolyte contents were not modified by ethacrynic acid. In all the experiments no changes in Cl^? and water contents were observed. It is concluded that the energy required to maintain the Na?K balance mechanisms within protoscoleces is largely provided by the anaerobic glycolytic pathway and that the aerobic oxidative pathway contribution to the energy balance is only accessory.     

DNA-based identification of larval cod in stomach contents of predatory fishes

Predator-prey interactions play an influential role in determining the demographics of a population or species. In the Northwest Atlantic, Atlantic cod, Gadus morhua, once the basis of a lucrative commercial fishery, have not recovered despite regulations imposed on the fishery to reduce harvest rates. One possible reason for the lack of recovery is that high predation pressure on juvenile and larval stages, particularly from species such as herring and mackerel, may regulate the abundance of cod. However, traditional methods used to identify larval cod and haddock often fail when applied to partially digested remains. Here, we described a DNA-based assay to identify the presence of digested cod remains from the stomachs of predatory fish species. After development, the assay was tested on two sets of field samples. Larval and juvenile cod were successfully detected in both tests.