Melanosome diversity and convergence in the evolution of iridescent avian feathers—Implications for paleocolor reconstruction

Some of the most varied colors in the natural world are created by iridescent nanostructures in bird feathers, formed by layers of melanin‐containing melanosomes. The morphology of melanosomes in iridescent feathers is known to vary, but the extent of this diversity, and when it evolved, is unknown. We use scanning electron microscopy to quantify the diversity of melanosome morphology in iridescent feathers from 97 extant bird species, covering 11 orders. In addition, we assess melanosome morphology in two Eocene birds, which are the stem lineages of groups that respectively exhibit hollow and flat melanosomes today. We find that iridescent feathers contain the most varied melanosome morphologies of all types of bird coloration sampled to date. Using our extended dataset, we predict iridescence in an early Eocene trogon (cf. Primotrogon) but not in the early Eocene swift Scaniacypselus, and neither exhibit the derived melanosome morphologies seen in their modern relatives. Our findings confirm that iridescence is a labile trait that has evolved convergently in several lineages extending down to paravian theropods. The dataset provides a framework to detect iridescence with more confidence in fossil taxa based on melanosome morphology.     

Basketball Shot Types and Shot Success in Different Levels of Competitive Basketball

The purpose of our research was to investigate the relative frequencies of different types of basketball shots (above head, hook shot, layup, dunk, tip-in), some details about their technical execution (one-legged, two-legged, drive, cut, …), and shot success in different levels of basketball competitions. We analysed video footage and categorized 5024 basketball shots from 40 basketball games and 5 different levels of competitive basketball (National Basketball Association (NBA), Euroleague, Slovenian 1^st Division, and two Youth basketball competitions). Statistical analysis with hierarchical multinomial logistic regression models reveals that there are substantial differences between competitions. However, most differences decrease or disappear entirely after we adjust for differences in situations that arise in different competitions (shot location, player type, and attacks in transition). Differences after adjustment are mostly between the Senior and Youth competitions: more shots executed jumping or standing on one leg, more uncategorised shot types, and more dribbling or cutting to the basket in the Youth competitions, which can all be attributed to lesser technical and physical ability of developing basketball players. The two discernible differences within the Senior competitions are that, in the NBA, dunks are more frequent and hook shots are less frequent compared to European basketball, which can be attributed to better athleticism of NBA players. The effect situational variables have on shot types and shot success are found to be very similar for all competitions.     

The Croatian model of university education for health professionals

In all European countries healthcare professions are regulated by law. In Croatia, the legally--regulated professions are: medicine, dentistry, pharmacy, nursing, physiotherapy and midwifery, as well as radiographers, occupational therapists and medical laboratory technicians. Current education of health professionals in Croatia is traditional, inadequate and poorly harmonized with current educational trends, as well as with requirements and directives of European Commission. This Croatian model for education of health professionals at university level follows the recommendations specified in Croatian Qualification Framework: (i) learning outcomes are competency-based; (ii) mobility of students and faculty is encouraged; (iii) the means of quality assurance are anticipated. The Croatian model of university education for health professionals will make sure that all procedures, specified in the European and Croatian Qualification Framework addressing recognizability of study programs, mobility, learning outcomes, quality assurance and reliability of required qualifications are successfully completed.     

Incorporation of crystallographic temperature factors in the statistical analysis of protein tertiary structures

A method to identify statistically significant differences between equivalent atoms in two closely related protein X-ray crystallographic structures is described. This method uses the linear relationship found between the logarithm of the distance between equivalent atoms and their mean temperature factor to determine, by linear regression, the expected difference and variance.     

Derivation of human embryonic stem cells in defined conditions

We have previously reported that high concentrations of basic fibroblast growth factor (bFGF) support feeder-independent growth of human embryonic stem (ES) cells, but those conditions included poorly defined serum and matrix components. Here we report feeder-independent human ES cell culture that includes protein components solely derived from recombinant sources or purified from human material. We describe the derivation of two new human ES cell lines in these defined culture conditions.     

Speed and agility of 12- and 14-year-old elite male basketball players

The aims of this study were (a) to identify and compare the speed and agility of 12- and 14-year-old elite male basketball players and (b) to investigate relations between speed and agility for both age groups of basketball players, to help coaches to improve their work. Sixty-four players aged 12 (M = 11.98 years, SD = 0.311) and 54 players aged 14 (M = 14.092 years, SD = 0.275) were tested. Three agility tests: agility t-test, zigzag agility drill, and agility run 4 × 15 m and 3 speed tests: 20-m run, 30-m run, and 50-m run were applied. Fourteen-year-old players achieved significantly better results in all speed and agility tests compared with 12-year-old players. The correlation coefficient (r = 0.81, p = 0.001) showed that 12-year-old players have the same ability in the 30- and 50-m runs. The other correlation coefficient (r = 0.59, p = 0.001) indicated that 20- and 30-m runs had inherently different qualities. The correlation coefficients between agility tests were <0.71, and therefore, each test in this group represents a specific task. In 14-year-old players, the correlation coefficients between the speed test results were <0.71. In contrast, the correlation coefficients between the agility tests were >0.71, which means that all the 3 tests represent the same quality. During the speed training of 12-year-old players, it is advisable to focus on shorter running distances, up to 30 m. During the agility training of the same players, it is useful to apply exercises with various complexities. In speed training of the 14-year-old players, the 30- and 50-m runs should be applied, and agility training should include more specific basketball movements and activities.     

Molecular and chemical characterization of the most widespread Ocimum species

DNA fingerprinting (AFLP) and chemical analyses of essential oils were utilized to define the extent of variation existing in the genus Ocimum. Research was carried out on 22 Ocimum accessions representing seven species. Concerning the essential oil composition of all investigated accessions, 115 compounds were identified. UPGMA cluster analysis, based on Euclidian distances of essential oil constituents between all pairs of accessions, showed four well-supported clusters (O. tenuiflorum, O. basilicum/O. africanum, O. basilicum, and O. americanum/O. africanum). Relating to the essential oil composition of all of the investigated accessions, 17 compounds were identified as the main ones, and according to them 13 chemotypes were determined. AFLP relationships were determined by neighbor-joining (NJ) cluster analysis based on Dice??s distance matrix and by maximum parsimony (MP) analysis. O. basilicum, O. americanum/O. africanum, O. tenuiflorum, and O. gratissimum represented four clusters supported with high bootstrap values. A neighbor-net diagram allowed the visualization of apparently conflicting data by revealing relationships between genotypes and chemotypes. Concerning the O. africanum species, two distinct chemotypes, geranial/neral (accession 11) and estragol (accession 10), have been established, while all the studied O. americanum accessions belong to the geranial/neral chemotype. This could be additional evidence that O. americanum is one of the parents of O. africanum. Furthermore, the fact that the O. africanum accession (10) as well as O. basilicum ??Purpurascens?? and O. basilicum ??Erevanskii?? accessions belong to the estragol chemotype supports the theory that O. africanum is one of the parents of these two O. basilicum accessions.     

Chemical characterization and genetic relationships among Ocimum basilicum L. cultivars

Twenty-seven Ocimum basilicum cultivars were subjected to a chemical characterization of essential oil components by gas chromatography/mass spectrometry (GC/MS) and a genetic characterization using the amplified fragment-length polymorphism (AFLP) technique. Since the same 27 accessions had previously been classified into six morphotypes, these analyses allowed us to make detailed comparisons of chemistry, genetics, and morphology. The chemical composition and morphology of the studied cultivars appeared to have a strong genetic component. The AFLP analysis revealed a distinction between the green and purple morphotypes. The green morphotypes predominantly utilized the terpene biosynthetic pathway, while most purple morphotypes primarily utilized the phenylpropene biosynthetic pathway. The GC/MS analysis led to identification of 87 volatiles. Among the 27 cultivars, five chemotypes were identified. A detailed characterization of the essential oil constituents indicated the existence of both specific combinations of compounds and 'private' compounds with the potential to be used in many aspects of human life. The established relationship between a genetic profile, chemical composition, and morphology represents an important step in future breeding programs and in the cultivation of this species.     

Neuropeptide Y is expressed by osteocytes and can inhibit osteoblastic activity

Osteocytes are the most abundant osteoblast lineage cells within the bone matrix. They respond to mechanical stimulation and can participate in the release of regulatory proteins that can modulate the activity of other bone cells. We hypothesize that neuropeptide Y (NPY), a neurotransmitter with regulatory functions in bone formation, is produced by osteocytes and can affect osteoblast activity. To study the expression of NPY by the osteoblast lineage cells, we utilized transgenic mouse models in which we can identify and isolate populations of osteoblasts and osteocytes. The Col2.3GFP transgene is active in osteoblasts and osteocytes, while the DMP1 promoter drives green fluorescent protein (GFP) expression in osteocytes. Real‐time PCR analysis of RNA from the isolated populations of cells derived from neonatal calvaria showed higher NPY mRNA in the preosteocytes/osteocytes fraction compared to osteoblasts. NPY immunostaining confirmed the strong expression of NPY in osteocytes (DMP1GFP⁺), and lower levels in osteoblasts. In addition, the presence of NPY receptor Y1 mRNA was detected in cavaria and long bone, as well as in primary calvarial osteoblast cultures, whereas Y2 mRNA was restricted to the brain. Furthermore, NPY expression was reduced by 30–40% in primary calvarial cultures when subjected to fluid shear stress. In addition, treatment of mouse calvarial osteoblasts with exogenous NPY showed a reduction in the levels of intracellular cAMP and markers of osteoblast differentiation (osteocalcin, BSP, and DMP1). These results highlight the potential regulation of osteoblast lineage differentiation by local NPY signaling. J. Cell. Biochem. 108: 621–630, 2009. © 2009 Wiley‐Liss, Inc.