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Domestic pigs and wild boars have undergone frequent interspecies crossbreeding; therefore, the presence of hybrids makes it challenging to find genetic markers that distinguish both subspecies. The aim of this research is to identify the DNA regions that underwent strong selection during the domestication of the pig and to give an insight into the genetic diversity of the Polish wild boar and domestic pigs by implementing the genotyping-by-sequencing (GBS) technique. We studied two groups of animals: one consisted of domestic pigs (Landrace, Large White, Duroc, Puławska and Pietrain), while the second group included wild boars from Poland. The filtered single nucleotide polymorphisms (SNP) panel used in this study included 7,298 markers that were spread across 18 porcine autosomes and unmapped contigs. The maximum-likelihood phylogenetic trees and multidimensional scaling (MDS) clearly separated the populations of pigs from the wild boars. We also detected genome regions that demonstrated the most significant genetic differences between the domestic pigs and wild boars. These regions were distributed on eight different autosomes and overlapped with 48 different pig RefSeq genes. The KEGG pathway, Reactome and GO terms were further used to assign a functional significance to the identified genes that were associated with inter alia muscle development (MYOG, MEOX2), pre-weaning mortality stress (MYO7A) and sensory perception (TAS1R3).

The importance of social and spatial structuring of wildlife populations for disease spread, though widely recognized, is still poorly understood in many host-pathogen systems. In particular, system-specific kin relationships among hosts can create contact heterogeneities and differential disease transmission rates. Here, we investigate how distance-dependent infection risk is influenced by genetic relatedness in a novel host-pathogen system: wild boar (Sus scrofa) and African swine fever (ASF). We hypothesized that infection risk would correlate positively with proximity and relatedness to ASF-infected individuals but expected those relationships to weaken with the distance between individuals due to decay in contact rates and genetic similarity. We genotyped 323 wild boar samples (243 ASF-negative and 80 ASF-positive) collected in north-eastern Poland in 2014-2016 and modelled the effects of geographic distance, genetic relatedness and ASF virus transmission mode (direct or carcass-based) on the probability of ASF infection. Infection risk was positively associated with spatial proximity and genetic relatedness to infected individuals with generally stronger effect of distance. In the high-contact zone (0-2 km), infection risk was shaped by the presence of infected individuals rather than by relatedness to them. In the medium-contact zone (2-5 km), infection risk decreased but was still associated with relatedness and paired infections were more frequent among relatives. At farther distances, infection risk further declined with relatedness and proximity to positive individuals, and was 60% lower among un-related individuals in the no-contact zone (33% in10-20 km) compared among relatives in the high-contact zone (93% in 0-2 km). Transmission mode influenced the relationship between proximity or relatedness and infection risk. Our results indicate that the presence of nearby infected individuals is most important for shaping ASF infection rates through carcass-based transmission, while relatedness plays an important role in shaping transmission rates between live animals.

The probative value of animal forensic genetic evidence relies on laboratory accuracy and reliability. Inter-laboratory comparisons allow laboratories to evaluate their performance on specific tests and analyses and to continue to monitor their output. The International Society for Animal Genetics (ISAG) administered animal forensic comparison tests (AFCTs) in 2016 and 2018 to assess the limitations and capabilities of laboratories offering forensic identification, parentage and species determination services. The AFCTs revealed that analyses of low DNA template concentrations (≤300 pg/µL) constitute a significant challenge that has prevented many laboratories from reporting correct identification and parentage results. Moreover, a lack of familiarity with species testing protocols, interpretation guidelines and representative databases prevented over a quarter of the participating laboratories from submitting correct species determination results. Several laboratories showed improvement in their genotyping accuracy over time. However, the use of forensically validated standards, such as a standard forensic short tandem repeat (STR) kit, preferably with an allelic ladder, and stricter guidelines for STR typing, may have prevented some common issues from occurring, such as genotyping inaccuracies, missing data, elevated stutter products and loading errors. The AFCTs underscore the importance of conducting routine forensic comparison tests to allow laboratories to compare results from each other. Laboratories should keep improving their scientific and technical capabilities and continuously evaluate their personnel’s proficiency in critical techniques such as low copy number (LCN) analysis and species testing. Although this is the first time that the ISAG has conducted comparison tests for forensic testing, findings from these AFCTs may serve as the foundation for continuous improvements of the overall quality of animal forensic genetic testing. Key PointsComparison tests allow laboratories to evaluate their analyses for accuracy and reliability.Two forensic identification, parentage and species determination comparison tests were performed.The study showed that the LCN DNA analysis represented a significant challenge to most laboratories.Lacking familiarity with species tests curbed most laboratories from reporting accurately.A reliance on forensically validated testing standards may have prevented some of the common errors.

Canine DNA is widely used in forensic investigations, particularly in cases of dog attacks on humans. Nowadays, STR markers are employed worldwide in forensic laboratories to test human and animal genotypes. In the study we analysed the effectiveness of 18 STR panel as previously recommended by ISAG and the same panel with three additional markers – 21 STR, which has been recommended by ISAG as the core panel for dog identification since 2016. We calculated the PD, PID for these sets of panels and estimated RMP based on the DNA profile obtained during an investigation of a woman bitten by a dog. The high combined CPD value for 18 and 21 STRs showed values close to 1.0. The CPID value for theses panels was 5.2 × 10−10 to 6.4 × 10−14. Statistical analysis estimated the random DNA match, in the case of the woman bitten by a dog, with a probability of 4.3×1019 and 2.8×1022, using 18 and 21 STR panels respectively, and that the canine DNA profile from the crime scene originated from the suspected dog and not from another random dog. Our results show that both STR panels can be used effectively for individual identification and forensic casework.

Swine DNA profiling is highly important for animal identification and parentage verification and also increasingly important for meat traceability. This work aimed to analyze the genetic structure and genetic diversity in selected Polish pig breeds. The study used a set of 14 microsatellite (STR) markers recommended by ISAG for parentage verification in the native Puławska pig (PUL, n = 85) and three commercial pig breeds: Polish Large White (PLW, n = 74), Polish Landrace (PL, n = 85) and foreign breed Duroc (DUR, n = 84). Genetic differentiation among breeds accounted for 18% of the total genetic variability (AMOVA). Bayesian structure analysis (STRUCTURE) indicated that the four distinct genetic clusters obtained corresponded to the four breeds studied. The genetic Reynolds distances (Ɵw) showed a close relationship between PL and PLW breeds and the most distant for DUR and PUL pigs. The genetic differentiation values (FST) were lower between PL and PLW and higher between PUL and DUR. The principal coordinate analysis (PCoA) supported the classification of the populations into four clusters.

The aim of the study was to determine the degree of relatedness between individuals in the Polish Hunting Dog population and to assess the genetic variability of the population based on pedigree analysis and molecular DNA testing. Pedigree data on Polish Hunting Dogs provided by the Polish Kennel Club was used. In total, data on 2783 individuals were obtained. DNA was obtained from cheek swabs taken from 177 dogs of the tested breed. A panel of 21 markers (Short Tandem Repeat - STR) was used. On the basis of genotypes in microsatellite loci, assessment of the Hardy-Weinberg genetic equilibrium was also carried out in the analyzed dog population using the χ2 test. The pedigree data contributed to identification of 26 founders. The Founder Genome Equivalent was 4.17, Founder Genomes Surviving was 17.03 and effective population size (Mean Ne) was estimated at 28.51. The gene diversity was 0.8802, the population mean kinship was 0.1198, and the mean inbreeding was 0.1151. Studies of STR markers revealed polymorphic information content – PIC = 0.56, and the estimated values of expected heterozygosity were generally close to the observed heterozygosity values and on average amounted to 0.6050 and 0.6142, respectively. The calculated average inbreeding coefficient (FIS) value was negative −0.012, which suggests a low level of inbreeding in the examined breed as well as avoidance of related animals in mates.

Background: Mastitis is one of the most serious diseases of dairy cattle, causing substantial financial losses. While predisposition to reduced somatic cell count in milk has been considered for in cattle breeding programs as the key indicator of udder health status, scientists are seeking genetic markers of innate immune response, which could be helpful in selecting cows with improved immunity to mastitis. Lipocalin-2 (LCN2) is a protein involved in the response of the immune system by eliminating iron ions which are necessary for the growth of pathogenic bacteria, so LCN2 may be considered as a natural bacteriostatic agent and could become a marker of infection. Results: A total of five SNPs were identified in LCN2 gene (one in the promoter, three in exon 1, and one in intron 1). A single haplotype block was identified. The locus g.98793763G>C was found to have a significant impact on protein levels in milk, and alleles of this locus were identified to have a significant positive dominance effect on this trait. None of the four analysed loci had a statistically significant impact on the milk yield, fat levels in milk or the somatic cell score. LCN-2 gene had no significant impact on the incidence of mastitis in the cows. Conclusions: Although the identified SNPs were not found to have any impact on the somatic cell count or the incidence of mastitis in cows, it seems that further research is necessary, covering a larger population of cattle, to confirm the association between lipocalin-2 and milk production traits and mastitis.How to cite: Pokorska J, Piestrzyńska-Kajtoch A, Kułaj D, et al. Polymorphism of bovine lipocalin-2 gene and its impact on milk production traits and mastitis in Holstein Friesian cattle. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.04.004 Keywords: Alleles, Breeding, Cattle, Gene polymorphism, Haplotype, Lipocalin-2, Mastitis, Milk, SNP, Somatic cell score, Udder

Swine DNA profiling is of high importance for animal identification and parentage verification. The aim of this study was to test a set of 14 microsatellite (STR) markers recommended by ISAG for parentage verification in Polish Landrace (PL, n = 900), Polish Large White (PLW, n = 482), Pulawska (PUL, n = 127), and Duroc pigs (DU n = 108). The studied breeds showed a medium level of genetic differentiation. The average value of heterozygosity and degree of polymorphism (PIC) were above 0.5 for the studied breeds, except for the DU breed (PIC = 0.477). The population inbreeding coefficient indicates an absence of inbreeding in the studied breeds (an average value of FIS = 0.007). The cumulative power of discrimination for all breeds reached high values close to 1.0, while the probability of identity (PID) was low, with PID values ranging between 10−9 (for DU) and 10−12 (for PLW). The cumulative exclusion probability for PE1 and PE2 showed that the parentage can be confirmed with a probability of from 92.75% to 99.01% and from 99.49% to 99.97%, respectively.

The aim of the study was to assess the genetic variability of the Polish Greyhound population based on pedigree analysis and molecular DNA testing and to determine the degree of relatedness among individuals in the population. Pedigree data of 912 Polish Greyhounds recorded in pedigree books since they were opened for this breed were analyzed. For molecular testing, DNA was obtained from cheek swabs taken from 235 dogs of the tested breed. A panel of 21 markers (Short Tandem Repeat&mdash, STR) was used. The mean inbreeding determined for the Polish Greyhound population based on pedigree analyses was low and amounted to 11.8%, but as many as 872 individuals of the 912 dogs in the studied population were inbred. A total of 83 founders (at least one unknown parent) were identified, among which 27 founders had both unknown parents. Full-sibling groups consisted of 130 individuals, with a minimum and maximum litter size of 2 and 16, respectively. The average litter size was 5.969. Gene diversity calculated based on the mean kinship matrix was 0.862 and the population mean kinship was 0.138. The founder genome equivalent based on the mean kinship matrix was 3.61, the founder genome surviving level was 12.34, the mean Ne was estimated at 21.76, and the Ne/N ratio was 0.135. The FIS inbreeding coefficient for 21 STR was negative, and the mean FIS value for all loci had a low negative value (&minus, 0.018). These values suggest a low level of inbreeding in the examined breed as well as the avoidance of mating related animals.

Pigeons played a major role in communication before the invention of the telephone and the telegraph, as well as in wars, where they were used to carry information and orders over long distances. Currently, numerous sports competitions and races are held with their participation, and their breeding is demanding not only for breeders, but also for the birds themselves. Therefore, an analysis of the genetic structure of racing pigeons kept in Poland was undertaken on the basis of 16 microsatellite markers, as well as the evaluation of the microsatellite panel recommended by ISAG. For this purpose, Bayesian clustering, a dendrogram, and Principal Coordinate Analysis were conducted. In addition, statistical analysis was performed. Based on this research, it was observed that racing pigeons are genetically mixed, regardless of their place of origin. Moreover, genetic diversity was estimated at a relatively satisfactory level (Ho = 0.623, He = 0.684), and no alarmingly high inbreeding coefficient was observed (F = 0.088). Moreover, it was found that the panel recommended by ISAG can be successfully used in Poland for individual identification and parentage testing (PIC = 0.639, CE-1P = 0.9987233, CE-2P = 0.9999872, CE-PP = 0.99999999).

The tortoiseshell coat colour is characteristic to female cats, and its occurrence in tomcats is very rare and associated with chromosome abnormalities (additional copy of X chromosome). The aim of this study was identification of the genetic basis of a case of tortoiseshell colour in a fertile Maine coon tomcat. Cytogenetic and molecular genetic studies were carried out with painting molecular probes (WCPP) specific to the X and Y sex chromosomes as well as a DNA microsatellite panel for the parentage verification of cats. Cytogenetic analysis revealed only a single set of sex chromosomes typical for male - 38,XY. The results of the microsatellite polymorphism obtained from DNA showed three alleles in locus FCA201 and four alleles in loci FCA149 and FCA441 in different tissues (blood, hair roots and testicles). Based on these results, the case was diagnosed as a true chimerism 38,XY/38,XY. To the best of our knowledge, this is the first case of a 38,XY/38,XY chimera diagnosed in cats, confirmed by genetic analysis.

The Tatra Shepherd Dog is one of five Polish native breeds of dogs originating from the Polish Tatra Mountains. The objective of the study was to determine genetic variation in a population of 60 dogs of this breed, based on polymorphism of 18 microsatellite (STR) markers, recommended by ISAG for canine parentage testing. The analysis showed considerable genetic variability in the studied loci. The 100 alleles identified in the test material were used to determine the polymorphism of the discussed markers. The highest polymorphism was found in the locus AHT171, in which 8 alleles were identified and PIC and HO values exceeded 0.8. The lowest polymorphism was detected for AHTk211, in which 3 alleles were determined, and PIC and HO values were 0.233 and 0.281, respectively. Average FIS had a low negative value, which suggests zero inbreeding of the studied breed. The probability of parentage exclusion estimated for the 18 markers totalled 99.996%.

The aim of this study was to determine a match between DNA recovered from evidence material, such as knocked down red deer, and from comparative material in form of two brown traces on the bonnet of a car driven by a person suspected of knocking down the animal. The spots coming from the car provided no DNA profile, which questioned that they originated from a red deer and ruled out performance of a comparative DNA analysis. For this reason, the material obtained from the blood smear was analyzed for species identification. The method applied can discriminate between cattle, red deer and roe deer based on restriction analysis (Tsp509I) of PCR product (195bp), obtained by amplifying a fragment of the cytochrome b coding gene. Because the obtained restriction profile confirmed the match with red deer DNA for one trace, and in the second case ruled out that the biological traces originated from the species mentioned above, the PCR products were subjected to sequencing. In both cases, 195bp PCR products that were 98% homologous with red deer DNA sequence-NC_007704.2-trace1 and with the gene coding for the human ryanodine receptor-NC_008799.2-trace2. The quantity and quality of DNA obtained from the traces collected from the car bonnet did not allow confirmation of the involvement of a specific animal in the event, but the applied method made it possible to determine the species from which the obtained traces originated. Furthermore, the applied method, which was used earlier to determine cervine DNA, was successfully used to detect human DNA.

There is growing concern that extreme breed standardization contributes to a reduction of the effective population size and high levels of inbreeding, resulting in the loss of genetic diversity in many breeds. This study examined genetic diversity among eight popular dog breeds in Poland and evaluated the effectiveness of a 21-microsatellite (STR) panel recommended by the International Society for Animal Genetics (ISAG) for parent verification. The following breeds were characterized: German Shepherd, Maltese, Irish Wolfhound, Yorkshire Terrier, Biewer Yorkshire Terrier, Golden Retriever, Labrador Retriever, and French Bulldog. STRUCTURE analysis showed breed distinctiveness among all the dog breeds under study. Reynold’s distance ranged between θw = 0.634 and θw = 0.260. The studied breeds showed a medium level of genetic differentiation, the mean number of alleles per locus ranged from 3.4 to 6.6, and the effective number of alleles from 2.1 to 3.5. The mean degree of heterozygosity varied from 49% to 69% and from 47% to 68% for HO and HE, respectively. The population inbreeding coefficient (FIS) indicated an absence of inbreeding in the studied breeds. The average polymorphism information content (PIC) values for most of the breeds were higher than 0.5. The cumulative power of discrimination (PD) for all the markers in all breeds reached high values (close to 1.0), while the probability of identity (PID) was low, ranging between 10−11 and 10−19. The cumulative exclusion probability when the genotypes of one (PE1) and both parents (PE2) are known and showed that the parentage can be confirmed with a probability of 94.92% to 99.95% and 99.78% to 99.9999%, respectively.

Ferromagnets are commonly magnetized by either external magnetic fields or spin polarized currents. The manipulation of magnetization by spin-current occurs through the spin-transfer-torque effect, which is applied, for example, in modern magnetoresistive random access memory. However, the current density required for the spin-transfer torque is of the order of 1 × 106 A·cm−2, or about 1 × 1025 electrons s−1 cm−2. This relatively high current density significantly affects the devices' structure and performance. Here we demonstrate magnetization switching of ferromagnetic thin layers that is induced solely by adsorption of chiral molecules. In this case, about 1013 electrons per cm2 are sufficient to induce magnetization reversal. The direction of the magnetization depends on the handedness of the adsorbed chiral molecules. Local magnetization switching is achieved by adsorbing a chiral self-assembled molecular monolayer on a gold-coated ferromagnetic layer with perpendicular magnetic anisotropy. These results present a simple low-power magnetization mechanism when operating at ambient conditions., Spin manipulation in memory devices typically requires large electrical currents, limiting performance. Here the authors demonstrate magnetization switching in ferromagnetic films by depositing chiral molecules, making use of a proximity effect without needing magnetic or electric fields.

In the recent years, antioxidant properties of food products have become an important aspect for consumers. Milk is a very good source of easily absorbable proteins and minerals, as well as a valuable source of antioxidants. Lipocalin-2 (LCN2), given that, inter alia, it is produced in large quantities by various types of cells in response to oxidative stress caused by physical or chemical factors, it can be considered a protein that determines the total antioxidant capacity of milk. The main objective of this study was to analyze polymorphisms within the lipocalin-2 gene and to determine their impact on antioxidant activity of milk from Holstein-Friesian cows. The genotyping was carried out by sequencing of PCR products. To determine the antioxidant activity of milk, the Trolox equivalent antioxidant capacity (TEAC) method was used. A total of four polymorphic sites were identified in the examined segment of the bovine lipocalin-2 gene. It was shown that cows of the CC genotype at the locus g.98793763G&gt, C produced milk of significantly higher antioxidant capacity. The antioxidant capacity of milk also varied according to the age of cows, their daily milk yield, and SCC in milk.

Summary A total of 181 Romanov lambs, including 84 pairs of twins, three litters of triplets and one litter of quadruplets, were investigated. Erythrocyte antigens belonging to six blood group systems were determined with 16 reagents. Six microsatellite loci BMS360, INRA123, McM42, CSSM66, ETH225 and TGLA53 were used to genotype the lambs with automated DNA sizing technology. For cytogenetic diagnosis of leucocyte chimerism, the fluorescence in situ hybridization (FISH) was applied using bovine X and Y chromosome painting probes. The blood-group typing of lambs from twin and multiple pregnancies allowed us to detect nine cases of erythrocyte chimerism in the investigated population. The analysis of microsatellite DNA sequences showed the presence of cell chimerism in 13 animals. The hybridization of a bovine X and Y chromosome-specific probe resulted in two yellow brightly luminescent signals in 54,XX cells, and one yellow and one blue signal in 54,XY cells helped us diagnose chromosomal chimerism in seven animals. Zusammenfassung Es wurden insgesamt 181 Lammer der Rasse Romanov untersucht, unter denen sich 84 Zwillingspaare, drei Drillingswurfe und ein Vierlingswurf befanden. Erythrozytenantigene von 6 Blutgruppensystemen wurden mit 16 Reagenzien bestimmt. Zur Genotypisierung der Lammer durch automatisierte DNA-Langenanalyse wurden die 6 Mikrosatellite BMS360, INRA123, McM42, CSSM66, ETH225 und TGLA53 herangezogen. Zum zytogenetischen Nachweis von Leukozyten-Chimarismus durch Fluoreszenz- in situ-Hybridisierung (FISH) wurden zur Markierung Proben eingesetzt, die fur das bovine X- und Y-Chromosom spezifisch waren. Die Blutgruppentypisierung von Zwillings- und Drillingslammern fuhrte zur Identifizierung von 9 Fallen von Erythrozyten-Chimarismus in der untersuchten Population. Die Mikrosatelliten-Analyse zeigte das Vorhandensein von Zell-Chimarismus bei 13 Tieren. Die Hybridisierung mit einer fur das bovine X- und Y-Chromosom spezifischen Probe resultierte in zwei gelben, stark lumineszenten Signalen in 54,XX-Zellen und einem gelben sowie einem blauen Signal in 54,XY-Zellen, was uns auf Chromosomen-Chimarismus bei 7 Tieren schliesen lies.

Recently, there has been considerable interest in genetic differentiation in the Cervidae family. A common tool used to determine genetic variation in different species, breeds and populations is DNA analysis, which allows for direct determination of the differences and changes within a group of animals. Because the analysis of microsatellite polymorphism in different Cervidae populations revealed considerable genetic variability in individual populations, it was important to test a set of markers in animals from these populations.The study was performed with muscle tissue and blood samples collected from a total of 793 red deer. Six groups (subpopulations) of red deer were defined according to region: Masurian (330 animals), Bieszczady (194 animals), Małopolska (80 animals), Sudety (76 animals), Lower Silesian (62 animals) and Lubusz (51 animals). The analysis involved 12 STR markers (BM1818, OarAE129, OarFCB5, OarFCB304, RM188, RT 1, RT 13, T26, T156, T193, T501, TGLA53), for which conditions for simultaneous amplification were established.Based on this study, it is concluded that the chosen set of 12 microsatellite markers could be used to evaluate the genetic structure and to monitor changes in Poland's red deer population.

Near-field optics using force sensing cantilevered optical fibers and micropipettes is used to investigate the chemical distribution of protein complexing dyes in chromosomes and the sensing and chemical imaging of surfaces and near- surface regions. These results are put in the context of what presently can be considered as a broad picture of near-field optical chemical applications.

Superresolution reflection near-field scanning optical microscopy (NSOM) of ultra-large-scale integrated circuits (ULSI) that have been subjected to chemical mechanical polishing (CMP) are presented. These NSOM images are rich in contrast, unlike simultaneously recorded atomic force microscopy (AFM) images. The NSOM data are compared to reflection confocal far-field optical microscopy using ultraviolet radiation with a wavelength of 248 nm, which has a resolution close to 0.2 /spl mu/m. Even though there is a significant thickness of oxide between the tip and the layer being imaged the data recorded with visible light clearly exhibits higher resolution than those ultraviolet confocal images that have undergone computer deconvolution. The AFM images exhibit no topography representing circuit features because the CMP operation that these static random access memory chips (SRAMs) have been subjected to produces flat topographic free surfaces. In terms of NSOM imaging, this is most interesting since the contribution of topography is totally removed and index of refraction variations are the only source for these rich NSOM images. Clearly, these NSOM images with cantilevered NSOM elements are free from topographic artifacts. Furthermore, simultaneous imaging of NSOM, normal force topography, and functional electrical characteristics such as capacitance and resistance are presented on these SRAMs. This demonstrates the ability of NSOM to act as a tool that provocatively integrates the best of far-field, optical imaging on the one hand with the most advanced scanned probe electrical imaging of circuit function on the other.

Near-field optics has produced the highest optical resolution that has ever been achieved. The methods involved lie at the interface of far-field optical microscopy and scanned probe microscopy. This article describes the principles behind near-field scanning optical microscopy (NSOM) and highlights its potential in cell biology.

A novel approach of patterning graphene on conductive surfaces based on local electrochemical reduction of graphene oxide is reported. Graphene is “written” from typical graphene oxide dispersion by applying negative potential on conductive surfaces vs. a micrometer-sized counter electrode “pen” with scanning electrochemical microscopy (SECM). Micrometer scaled patterns are successfully generated on gold and stainless steel surfaces.

The electrochemically assisted codeposition of sol–gel thin films on stainless steel is described. Specifically, electrodeposition of films based on aminopropyltriethoxysilane (APTS), and its codeposition with propyltrimethoxysilane (PrTMOS) and phenyltrimethoxysilane (PhTMOS) has been accomplished by applying negative potentials. The latter increases the concentration of hydroxyl ions on the stainless steel surface and thus catalyzes the condensation and deposition of the sol–gel films. The films were characterized by profilometry, electrochemical impedance spectroscopy (EIS), alternating current voltammetry (ACV), goniometry, atomic force microscopy (AFM) and scanning electron microscopy (SEM). AFM and SEM analysis of codeposited APTS ∶ PrTMOS films disclosed the structural changes induced by altering the deposition solution composition and the applied potential. Codeposited APTS ∶ PhTMOS did not show any structural differences from their electrodeposited homopolymers, while Nano Scratch Test clearly revealed the changes in the elastic and adhesion properties, suggesting the formation of an APTS ∶ PhTMOS composite. EIS of the films showed good resistance towards penetration of hydrophilic species, such as hexacyanoferrate. ACV measurements of the homo and codeposits showed the decrease of the interfacial capacity as a result of the electrochemical deposition. In essence, controllable sol–gel films with tunable chemical and physical properties based on controlling the combination of the precursors, pH and electrochemical properties can be electrodeposited on conducting surfaces. The application of this approach has been demonstrated by coating a stainless steel coronary stent.

The present study attempts to analyse sequences of the X- and Y-chromosome specific regions of the amelogenin (AMEL) gene in red deer. To this end, primers specific for each form of the gene (AMELX and AMELY) were designed based on bovine genomic sequences and the homologous regions of the genes were sequenced. The obtained sequence of AMELX gene showed high similarity with the corresponding region in cattle (91%) and humans (77%), but this similarity was slightly lower among AMELY genes and showed 87 and 73% of identical nucleotides, respectively. In addition, three single nucleotide polymorphisms (SNPs) were found in the AMELX gene of the female red deer investigated. Comparative analysis of the homologous fragments of the red deer AMELX and AMELY genes confirmed the deletion of an AMELY gene fragment in relation to AMELX. Homology of both sequences was 82% of identical nucleotides in the coding region and 74% in 3′ non-coding sequence. The sequences studied showed considerable similarity to homologous fragments of the human and bovine gene, but the structural differences observed lead us to design PCR-based method for sex identification in red deer, based on the presented sequences.

In this report we demonstrate a general method for affecting chemical reactions with a high degree of spatial control that has potentially wide applicability in science and technology. Our technique is based on complexing the delivery of liquid or gaseous materials through a cantilevered micropipette with an atomic force microscope that is totally integrated into a conventional optical microscope. Controlled etching of chrome is demonstrated without detectable effects on the underlying glass substrate. This simple combination allows for the nanometric spatial control of the whole world of chemical reactions in defined regions of surfaces. Applications of the technique in critical areas such as mask repair are likely.

Objectives: This study was carried out to evaluate the extent of differences in mineralization of inner and outer enamel of the lower primary second molars of children with Down syndrome (DS) and Cerebral Palsy (CP) as revealed by acid treatment of exfoliated teeth. The results were compared to those obtained from a control group of healthy children. Methods: The sample included 4 mandibular second molars from each group. On each tooth, a thin section was cut, bisecting the mesial cusps. The analysis was carried out on the mesio-buccal cusps. Atomic force microscopy (AMF) was used to analyze the morphological structure of the dental enamel after 10 sec of 0.1 mol% citric acid treatment. The measurements were performed on 3 points in the enamel close to the outer surface and 3 points in the enamel close to the dentin. The differences between groups were analyzed using Mann Whitney tests. Results: In controls and CP teeth the outer enamel was more resistant to etching than the inner enamel. In DS teeth both outer and inner enamel showed similar results for all parameters. Between group comparisons showed that roughness values were significantly higher (P Conclusions: The higher values obtained for DS enamel reflect increased solubility of the enamel to acid relative to controls and CP teeth together with irregularity of the organic matrix. The practical importance of the results is that DS primary molars needs reduced etching time when prepared for pit and fissure sealants or composite/compomer restorations.

Genetic variation of endangered Biłgoraj horses and two common Polish horse breeds was compared with the use of 12 microsatellite loci (AHT4, AHT5, ASB2, HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, HTG10, VHL20). Lower allelic diversity was detected in all investigated populations in comparison to other studies. Large differences in the frequencies of microsatellite alleles between Biłgoraj horses and two other horse breeds were discovered. In all polymorphic loci all investigated breeds were in the Hardy-Weinberg equilibrium. Mean Fis values and the results of a test for the presence of a recent bottleneck were non-significant in all studied populations. Comparable values of observed and expected gene diversity indicate no substantial loss of genetic variation in the Biłgoraj population and two other breeds. The lowest variability observed in the investigated group of Thoroughbred horses was confirmed. About 10% of genetic variation are explained by differences between breeds. Values of pairwise Fst and two measures of genetic distance demonstrated that Biłgoraj horses are distantly related to both common horse breeds.

Polymorphism of 11 microsatellite DNA loci was analysed in Polish Red (PR), Hereford and Holstein-Friesian (HF) cattle raised in Poland and genetic distance among these breeds was determined. At the 11 loci (TGLA227, BM2113, TGLA53, ETH10, SPS115, TGLA126, TGLA122, INRA23, ETH3, ETH225 and BM1824) analysed with automated DNA sizing technology, a total of 213 alleles were identified: 76 in PR, 76 in HF, and 61 in Hereford. All the microsatellite DNA markers showed high polymorphism. Polymorphism information content (PIC) calculated for each marker exceeded 0.5, except for the ETH3 locus in Hereford cattle (PIC=0.475), and heterozygosity (H) ranged from 54.1% to as much as 85.2%. The coefficient of genetic distance was 0.354 between PR and Hereford, 0.414 between HF and Hereford, and 0.416 between PR and HF cattle.

We demonstrate that near-field optical and atomic force microscopy data can be used for super-resolution 3D image restoration in optical sectioning fluorescence microscopy. A crucial feature in this approach is the full integration of such data sets with digital far-field images. The scanned probe data is used to provide modalities for boundary constraints which define surface optical information and spatial domains of optical alterations in a sample with a spatial precision that has been unachievable in the past. A restoration algorithm that can use such a complex of data for 3D image deconvolution is presented. It uses a Tikhonov- Miller regularization scheme and allows for the imposition of different types of constraints to obtain super-resolution deconvolved images. Performance was tested by using simulated 3D imaging. An example is given of the restoration of a 3D wide field optical image of a biological specimen in the presence of atomic force constraints.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Simultaneous near-field scanning optical and atomic force imaging of bacteria is presented. The bacteria imaged in these studies were unstained. The near-field optical images had excellent signal-to-noise and showed excellent contrast even in these unstained specimens. The images obtained were interpreted in terms of the images that have been obtained by transmission electron microscopy and X-ray imaging. The results show that bacterial near-field optical imaging is going to be a very important tool in the arsenal of the bacteriologist both in terms of understanding the fundamental processes in the life cycle of bacteria with and without cytochemical staining and in terms of clinical diagnostic applications.

A methodology is described for phase restoration of an object function from differential interference contrast (DIC) images. The methodology involves collecting a set of DIC images in the same plane with different bias retardation between the two illuminating light components produced by a Wollaston prism. These images, together with one conventional bright-field image, allows for reduction of the phase deconvolution restoration problem from a highly complex nonlinear mathematical formulation to a set of linear equations that can be applied to resolve the phase for images with a relatively large number of pixels. Additionally, under certain conditions, an on-line atomic force imaging system that does not interfere with the standard DIC illumination modes resolves uncertainties in large topographical variations that generally lead to a basic problem in DIC imaging, i.e., phase unwrapping. Furthermore, the availability of confocal detection allows for a three-dimensional reconstruction with high accuracy of the refractive-index measurement of the object that is to be imaged. This has been applied to reconstruction of the refractive index of an arrayed waveguide in a region in which a defect in the sample is present. The results of this paper highlight the synergism of far-field microscopies integrated with scanned probe microscopies and restoration algorithms for phase reconstruction.