Effect of various pre-treatments on the seedling growth performance of Tamarindus indica L.

ABSTRACT

Pre-treatment of seeds of Tamarindus indica L. with 95% sulphuric acid for 5, 10 or 15 min, methanol, ethanol, iso-propanol or butanol for 10 or 20 min, or boiling water for 10, 15, 20 or 30 min, was used to determine the effect of the various treatments on the development and vigour of the resultant seedlings. Seeds immersed in methanol, ethanol and sulphuric acid for 10 min produced seedlings with high vigour     

Protein Turnover in Brain of the Rat Fetus

Protein synthesis in vivo was studied in whole brain of rat fetuses using continuous intravenous infusion of L-[U-14C]tyrosine into unrestrained pregnant rats at 19 and 21 days gestation. Protein degradation (KD) was calculated by subtracting fractional growth rate of brain protein (KG) from the fractional synthesis rate (KS). KS was high at both gestational ages (0.42 +/- 0.03 days-1 at day 19, 0.47 +/- 0.029 days-1 at 21 days), comparable to values previously reported for newborn rat cerebral hemispheres, and threefold higher than is seen in adult animals. KD was similar at both 19 and 21 days gestation (0.19-0.24) and lower than that reported in neonatal rat brain using similar techniques. Protein accretion during the most rapid phase of brain growth (fetus) is accomplished by similar rates of protein synthesis, but decreased rates of degradation when compared with a slower growth phase (newborn). KD in the brain of the rapidly growing fetus is slightly higher than in adult cerebral hemispheres.     

Radial growth of the Sahara’s oldest trees : Cupressus dupreziana A. Camus

The radial growth of Duprez’ cypress (Cupressus dupreziana A. Camus), a tree endemic to the Tassili n’Ajjer in the Central Sahara, was measured from cores taken in 1967 and 1997 from the same trees. A comparison of these cores, spanning 30 years, reveals that even in this hyper-arid climate, this species has a juvenile vigour comparable to other Mediterranean Cupressaceae. Wide individual variability was found, however, which was induced by the strong influence of microhabitat factors. Traditional dendrochronological methods of cross-dating are impossible to apply in the case of these trees. Ages of eight individuals were estimated with the help of radiocarbon dating, yielding an age range from 600 to 2400 years for trees of the most usual girths.     

Life history and population dynamics of the Japanese Yam,Dioscorea japonica Thunb.

The adaptive significance of the emergence mode ofDioscorea japonica was studied with respect to initial plant size (seed, bulbil and tuber) and light intensity, using mathematical simulation based on Yokoi's (1976) model. Under 1.5% full sunlight conditions, plants emerging with only one leaf did not develop a shoot system throughout the growing period (Hori and Oshima, 1986). Simulation indicated that, for this species of plant under poor productive conditions, the optimal time for switch-over from the vegetative to reproductive growth phase to maximize the tuber weight at the end of the growing period, occurred immediately following the start of autotrophic growth. By means of shoot growth patterns, small and large size plants acquired the ability of shade tolerance and shade avoidance, respectively. Further, the life history ofD. japonica could be expressed as a flow chart based on plant size and light intensity data.     

Simplicissin,a New Pollen Growth Inhibitor Produced by the Fungus,Penicillium cf. simplidssimum (Oudemans) Thorn No. 410

A new pollen growth inhibitor, named simplicissin, was isolated from Penicillium cf. simplicissimum (Oudemans) Thorn No. 410, and its structure was established by spectroscopic methods including 2D NMR. The biological activities of the compound were examined by the bioassay methods involving tea pollen together with lettuce seedlings. The compound inhibited the growth of the tea pollen tube by 45% at a concentration of 3 mg/liter and showed complete inhibition at 10mg/liter.     

Effect of the anisotropic permeability in the frequency dependent properties of the superficial layer of articular cartilage

Abstract

Articular cartilage is a tissue of fundamental importance for the mechanics of joints, since it provides a smooth and lubricated surface for the proper transfer of loads. From a mechanical point of view, this tissue is an anisotropic poroviscoelastic material: its characteristics at the macroscopic level depend on the complex microscopic architecture. With the ability to probe the local microscopic features, dynamic nanoindentation test is a powerful tool to investigate cartilage mechanics. In this work we focus on a length scale where the time dependent behaviour is regulated by poroelasticity more than viscoelasticity and we aim to understand the effect of the anisotropic permeability on the mechanics of the superficial layer of the articular cartilage. In a previous work, a finite element model for the dynamic nanoindentation test has been presented. In this work, we improve the model by considering the presence of an anisotropic permeability tensor that depends on the collagen fibers distribution. Our sensitivity analysis highlights that the permeability decreases with increasing indentation, thus making the tissue stiffer than the case of isotropic permeability, when solicited at the same frequency. With this improved model, a revised identification of the mechanical and physical parameters for articular cartilage is provided. To this purpose the model was used to simulate experimental data from tests performed on bovine tissue, giving a better estimation of the anisotropy in the elastic properties. A relation between the identified macroscopic anisotropic permeability properties and the microscopic rearrangement of the fiber/matrix structure during indentation is also provided.     

A combination of genome-wide association study and selection signature analysis dissects the genetic architecture underlying bone traits in chickens

The bones of chicken play an important role in supporting and protecting the body. The growth and development of bones have a substantial influence on the health and production performance in chickens. However, genetic architecture underlying chicken bone traits is not well understood. The objectives of this study are to dissect the genetic basis of bone traits in chickens and to identify valuable genes and genetic markers for chicken breeding. We performed a combination of genome-wide association study (GWAS) and selection signature analysis (fixation index values and nucleotide diversity ratios) in an F₂ crossbred experimental population with different genetic backgrounds (broiler × layer) to identify candidate genes and significant variants related to femur, shank, keel length, chest width, metatarsal claw weight, metatarsal length, and metatarsal circumference. A total of 545 individuals were genotyped based on the whole genome re-sequencing method (26 F₀ individuals were re-sequenced at 10 × coverage; 519 F₂ individuals were re-sequenced at 3 × coverage). A total of 2 028 112 single-nucleotide polymorphisms (SNPs) remained to carry out analysis after quality control and imputation. The integration of GWAS and selection signature analysis indicated that all significant SNPs responsible for bone traits were mainly localized on chicken chromosomes 1, 4, and 27. Finally, we identified 21 positional candidate genes that might regulate chicken bone growth and development, including LRCH1, RB1, FNDC3A, MLNR, CAB39L, FOXO1, LHFP, TRPC4, POSTN, SMAD9, RBPJ, PPARGC1A, SLIT2, NCAPG, NKX3-2, CPZ, SPOP, NGFR, SOST, ZNF652, and HOXB3. Additionally, an array of uncharacterized genes was identified. The findings provide an in-depth understanding of the genetic architecture of chicken bone traits and offer a molecular basis for applying genomics in practical chicken breeding.     

Insulin-Like Growth Factor I Receptor Binding in Brains of Alzheimer''s and Alcoholic Patients

Patients with chronic alcoholism and/or Alzheimer's disease show degenerative changes in the cerebral cortex and hippocampus. To investigate possible changes in insulin-like growth factor I receptor binding sites in brain tissue of patients with these pathological conditions, the number of 125I-insulin-like growth factor I binding sites was determined in tissues obtained from control patients and those with Alzheimer's and/or with a history of alcoholism. The four experimental groups examined consisted of patients from similar age groups. Postmortem histology and a clinical history were used for the diagnosis of Alzheimer's disease and alcoholism, respectively. Careful clinical records were kept concerning other variables such as immediate cause of death and medications administered before death. Specific binding of 125I-insulin-like growth factor I to homogenates prepared from cerebral cortex of Alzheimer's, alcoholic, alcoholic Alzheimer's, and age-matched control patients was similar, although Alzheimer's patients tended to have slightly higher binding values. No significant differences in insulin-like growth factor I binding in cerebral cortex were found with regard to age of patients, the interval between death and autopsy, and CNS-active medications. No statistical differences in 125I-insulin-like growth factor I binding were noted in hippocampal tissue from the four patient groups. Thus, human insulin-like growth factor I binding sites in cerebral cortex and hippocampus appear unaffected by several variables.