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The failure pattern in slate tested under diametral compression is strongly influenced by the contact angle created in the loaded area. A small angle is created throughout the contact between the jaws (or platens) and the disc by adopting flat platens (ASTM standard) or curved jaws (suggested method by ISRM) load configurations, inducing failures due to shear stresses in the limit of the load rim. This causes failure patterns that do not exactly match the central diameter when the material is tested with the load direction parallel and perpendicular to foliation, which contradicts the failure by pure tensile typically assumed in the test for these orientations. In the present work, a new interpretation of the failure pattern in slate samples tested with the Brazilian method is established, playing the contact angle a significant role. Brazilian tests with the loading direction along and across foliation were carried out in the laboratory, by using the load configurations of ASTM standard and the ISRM recommendation. Furthermore, an analytical study allowed the estimation of the point in the whole of the disc in which a critical stress state is firstly reached by taking into account both the foliation and the intact rock failure criteria, hence justifying the experimental failure patterns. Finally, regarding the initial failure the influence of the strength properties in order to satisfy the classic hypothesis of the Brazilian test in rocks with multiple weak planes was analysed. An appropriate interpretation of the failure pattern can be an important indicator in order to reveal the true failure mechanism of rocks; this may help to improve the characterization and prediction of the initial failure of this material, which is widely used as an industrial rock or in dam foundations, underground excavations and slope engineering.

Slate is a natural stone widely used for building, for which is subjected to regulations and standards in order to be commercialized. As far as the influence of water is considered, only detailed studies are compulsory when the water absorption is higher than 0.60%. However, the mechanical behavior of this layered material depends on water content, which is function of the relative humidity of the environment, and not considered in existing standards. In order to investigate its influence on foliation tensile strength, an experimental study was performed, which consists on carrying out Brazilian tests in slate samples with known water content, applied and controlled by using vapor equilibrium technique. This technique allows controlling the relative humidity of the environment surrounding the material and that of the air on its pores. Relative humidities between 55% and 92% were applied during the tests and defined considering climate data from the north of Spain. Despite the maximum water content tested in the slates was low (0.10%) in comparison with its saturation content (0.57%), the experimental results show a decreasing of the foliation tensile strength that reaches up to three times less with an increment of the environmental relative humidity of 37%. The results achieved can be important in order to quantify the layering weakness due to a natural alteration factor such as the environmental relative humidity. Moreover, the procedure employed is proposed as a convenient method for adequating each variety of slate stone to different climates according to its vulnerability to water.

Pedigree information among individuals has become a key factor in the correct management and conservation of wild populations, as well as captive stocks. Despite the growing interest in the identification and application of single nucleotide polymorphism (SNP) markers, to date, microsatellite loci continues to be considered as the genetic marker par excellence to establish the degree of relationship among individuals. In fact, although high-density SNP panels are a highly accurate tool for inferring kinship relationships, at small-scale, with only a reduced number of SNPs involved, it is difficult to preserve that accuracy due to the bi-allelic nature of this genetic marker. The present study has evaluated the accuracy of SNP-haplotypes (genotypic combination of single SNPs located in the same gene) as parentage and relatedness tool in gilthead sea bream (Sparus aurata). Initially, by direct sequencing of 11 genes in a set of 30 unrelated individuals with heterogeneous origin, a total of 398 putative SNPs were identified and, by means of a filtering procedure to remove false positive and SNPs in a very low frequency, 164 SNPs were selected for the final panel. Using the iPLEX Gold MassARRAY technology, a subset of 58 SNPs located in 7 genes were genotyped in 424 individuals organized into two broodstocks (54 breeders and 370 offspring with pedigree previously inferred by microsatellite loci). From the obtained genotype data, a SNP-haplotype reconstruction was carried out for each gene. According to this approach, 58 biallelic single SNPs were turned into 7 multi-allelic markers (1 gene = 1 marker) whose allele (haplotype) number ranged from 3 to 41. This SNP-haplotypes resolved parentage assignment with an accuracy higher than 99%, resulting in a 10.5% and 3.5% more accuracy than the set of 58 SNPs and 9 microsatellite loci, respectively. Likewise, under a scenario in which ancestral information was not available, SNP-haplotypes showed an accuracy similar than microsatellite loci for discriminating unrelated individuals. Using this approach, a proportion close to 94% of unrelated individuals correctly classified for the coefficient of relationship equal to zero (theoretically expected relatedness value between unrelated individuals) was achieved. The 6% of individuals, misclassified as unrelated, were largely half-sibs since the full-sibs did not exceed 0.03%. In conclusion, we report herein that SNP-haplotypes approach represents a highly efficient alternative to microsatellite loci to infer parentage and assess relatedness.

Published correction to this article: Giutiérrez-Moizant, R., et al.: Correction to "Computational verification of the optimum boundary condition of the Brazilian tensile test". In: Rock mechanics and rock engineering, vol. 51(12), Dec. 2018, pp. 3983-3984 The present research analyses the configuration of jaws to avoid the premature failure of the disc in the Brazilian test. The objective is to depict the loading device configuration that most likely produces results comparable to the Hondros' analytical stress solution. To this end, several numerical analyses have been carried out for different contact angles with the finite element method. It was deduced that the final contact angle plays an important part in the success of the Brazilian test and that the Griffith criterion can be fulfilled if the equivalent stress is calculated. Additionally, the orientation of the forces in the contact between the loading device and the disc has been studied for different friction conditions. According to the numerical results, it was found that a loading arc configuration of 20 degrees shows the best agreement with the probable values given by the analytical stress model when the uncertainty of its magnitudes is taken into account. The study also demonstrates that the friction in the contact between the optimal loading configuration and the disc does not seem to significantly affect the theoretical predictions in the centre of the disc. The authors of this paper acknowledge the financial support of the PhD fellowship Severo Ochoa Program of the Government of the Principality of Asturias (PA-14-PF-BP14-067).

The location of the failure initiation in the Brazilian test is strongly influenced by the contact angle created in the loaded area. As this angle increases, the position of the initial failure point is closer to the center of the disc, which is a result of both: uniform radial pressure and sinusoidal radial pressure; as well as adopting different failure criteria and materials. Moreover, the frictional stresses throughout the contact between the jaw (or platens) and the disc cannot be considered as a critical failure parameter for failures initiated from the origin to a radial distance of 0.8 R. In this paper, firstly, the influence of the above mentioned parameters in the location of the initial failure point was analytically studied. Secondly, the analytical results have been proven through experimental tests. Finally, once the importance of the contact angle in the location of the initiation point was checked, a procedure is suggested in order to increase the contact angle with the same load applied to one specific sample, by using various jaw curvatures. The location of failure initiation does not cause great disturbances in the determination of the indirect tensile strength. However, the position is important in order to adjust the failure criteria in the tension region. According to the location of the initial failure, the stress field in terms of principal stresses ( σ 1 and σ 3 ) will be different. So by knowing this position, the precise failure criteria could be established in σ 1 - σ 3 , specifically in the tension region. Meaning that as well as the triaxial test is mostly used to calculate the failure criteria in the compression region, the Brazilian test could be used to obtain the limiting stress states in the tension region.

The implementation of any sustainable breeding program requires a maximization of effective size (Ne) to maintain inbreeding rate at minimum levels. However, the control of Ne remains a major challenge for those species whose reproduction in captivity is based on a spawning strategy where there is no control over the established matings. The present study aims to assess the spawning dynamic of gilthead sea bream (Sparus aurata) at different dates from two mini-broodstocks (4 ♀ and 4 ♂). Here we report the use of a simple protocol based on the genotyping of fertilized eggs from a reduced set of microsatellite loci which provides a quick evaluation of daily spawning in terms of family structuring (number of active breeders and number and family size). According to our results, the daily spawning dynamics is characterized by a fluctuation in the number of active breeders, reaching maximum values (until 100%) during peak production phase. However, the proportion of possible mating (families) in a single daily spawning never exceeded more than 81%. Unbalanced parental contributions were highly frequent, with extreme cases involving the assignment of 50%–90% of the offspring to a single family. Therefore, the use of mini-broodstocks and the grouping of spawning harvested at different dates are proposed as strategies to minimize the inbreeding risk by providing a more optimal pattern of family structuring (increase in the number of families obtained and a more balanced parental contributions) that entails a more conservative Ne/N ratio.

European Conference on Unsaturated Soils (E-UNSAT) (4th. 2020. Lisboa, Portugal), The authors acknowledge the financial support of the PhD fellowship Severo Ochoa Program of the Government of the Principality of Asturias (PA-14-PF-BP14-067). C.C. GarciaFernandez is also grateful to Banco Santander for his Movility Programme for researchers of the University of Oviedo.

This research study presents a new theoretical model to calculate the indirect tensile strength for the Brazilian disk with loading arcs, based on numerical simulations, two-dimensional elasticity theory, and Griffith failure criterion. The new expression incorporates a no uniform contact pressure distribution determined by the results of the simulations with the finite element method. A computational experiment design has been developed to test the accuracy of the predictions made with the proposed model. This study demonstrates that the stresses predicted with the new model are closer to those determined by the finite element models than other theoretical solutions available in the literature. Additionally, a comparative analysis with experimental results obtained by other authors also indicates that the new model provides a more accurate magnitude of the indirect tensile strength. The authors of this paper acknowledge the financial support of the PhD fellowship of the Severo Ochoa Program of the Government of the Principality of Asturias (PA-14-PF-BP14-067).

A new method is proposed in order to estimate the shear strength of schistosity planes in slate in terms of Mohr-Coulomb cohesion and internal friction angle. The procedure consists in carrying out the Brazilian method under different loading-foliation angles, for which experimental tests were achieved in slates from the northwest of the Iberian Peninsula (Spain). The experimental fracture patterns were analytically studied and justified by simulating the stress field in the discontinuity planes contained in the whole sample, taking into account the first failure registered in the tests. By combining experimental and analytical studies and a procedure based on the representation of the threshold state of stressesin the elastic regimein the failure plane, it is possible to estimate the foliation's strength envelope through a lineal adjustment according to the Mohr-Coulomb criterion and, thus, to characterize the layering. Finally, the proposed procedure was validated by the direct shear test. The cohesion and the internal friction angle obtained with this convenctional test were very close to that calculated by the proposed method, verifying the methodology developed by the authors. This procedure may be interesting in various engineering applications, either in the study of the properties of cleavage in slate, which is commonly used as an industrial rock, or in dam foundations, underground excavations and slope engineering, since one of the main failures in civil engineering is due to sliding along weak planes. The authors of this paper would like to acknowledge the financial support of the PhD fellowship Severo Ochoa Program of the Government of the Principality of Asturias (PA-14-PF-BP14-067). Also, the authors are grateful to editors and reviewers for their suggestions and help us to improve this manuscript.

A new method is developed in order to determine the stress state inside a disk subjected to arbitrary radial compressive distributions along its boundary, obtaining both numerical and closed-form solutions, which is analytically verified through accepted formulations; additionally, alternative expressions for uniform, sinusoidal and parabolic distributions are proposed. Based on the hypothesis of a smooth stress transition along the loaded and unloaded part of the rim, two new distributions (spline and new cosine) are proposed and analysed. Even if closed-form solutions were not feasible, the latter may be accurately solved numerically since the error committed is that of the numerical technique used. Main differences are observed in radial and shear components, whereas hoop ones are relevant on the vicinity of the load application area and the vertical axis. Special attention is paid to the centre of the sample, of which stress state depends on the distribution shape and the contact angle. Finally, it is concluded that there is always a deviation from the values predicted due to the concentrated load as a consequence of the deformation induced by the jaw, which is especially significant in the uniform stress distribution and also influences the determination of the tensile strength in the material.

An erratum has been detected in the units of the Young’s modulus of Tables 5 and 6. The units should be in GPa and not in MPa.

In hospitalized diabetic patients, the recommended insulin therapy is basal bolus plus correction-dose regimen instead of sliding-scale insulin. The purpose of this study was to evaluate the effect of the implementation of a new protocol based on basal bolus therapy on managing diabetes in a university hospital setting. We performed a cross-sectional study before and 12 months after a 4-month intervention period to implement a basal bolus regimen in hospitalized patients. Non-critical patients admitted into the hospital for at least 72 h were included. Changes in prescribing habits, glucose control and incidence of hypoglycemia were evaluated. An increase in the use of the new protocol and a decrease in sliding scale were observed after the intervention. In the pre-intervention group, a total of 59.2% glucose readings were between 70 and 180 mg/dL versus 57.1% after the intervention, without observing statistical differences. Significant reductions in hypoglycemia between pre- and post-intervention (13.04 vs. 4.08%, p = 0.0215) were observed. The percentage of hospitalized diabetic patients who had HbA1c was 10.43 and 4.08% in pre- and post-intervention phases, respectively. The protocol showed beneficial outcomes in terms of fewer hypoglycemia episodes and reflected a change in prescription habits, but it did not improve glycemic control. Furthermore, the percentage of patients who had an HbA1c test during their hospitalization remained very low after the intervention. This fact may seriously limit the correct management of hyperglycemia after the hospital discharge.

First-principle calculations have been performed to characterize the interaction of chlorinated species (HCl and Cl) with large polycyclic aromatic hydrocarbon (PAH) molecules and radicals. Whereas the characterization of the interaction process on the face of the PAH molecules requires taking into account long-range dispersion interactions in the calculations, trapping at the edge of PAH radicals involves stronger interactions that lead to the dissociation of the HCl molecule. Then, the first steps of water adsorption on the corresponding chlorinated species has been characterized, showing that chlorine may act as an efficient nucleation center for water molecules on such aromatic systems mimicking part of the carbonaceous surfaces that are likely present in soot. These results represent a first but necessary step for a better understanding of soot behavior in industrial or domestic fire situations.

Molecular tools to assist breeding programs in the gilthead sea bream (Sparus aurata L.) are scarce. A new multiplex PCR technique (OVIDORPLEX), which amplifies nine known microsatellite markers, was developed in this work. This multiplex system showed a high mean heterozygosity (>0.800) and a high mean number of alleles per marker (>14) when tested in two sea bream broodstocks (A: 40 breeders and B: 38 breeders). We tested this multiplex PCR for inferring parentage in a Spanish hatchery that graded the animals by size as part of their management procedure. The progeny of the broodstock were divided into fast- and slow-growth groups. Parentage studies revealed that this management procedure entailed a global reduction of the breeders' representation in progeny and that breeders' contributions were significantly unequal. Due to this, effective sample sizes fell to N ê¿13-14 for fast- and N ê¿18-24 for slow-growth progeny groups. These results imply a 3 to 4% rate of inbreeding per generation in the fast-growth group, which is more important to hatchery managers than the slow group. Not all the progeny were evaluated in this experiment (due to the discarding steps), and thus it is difficult to know if the phenotypic performance showed by the fast-growing progeny will be heritable. However, there were genetic differences between the differentiated growth progeny groups (fast vs. slow, F ST values=0.016 to 0.023; P, This work was carried out in collaboration with the fish farm Granja Marina Safor, S.L. (Gandia, Valencia, Spain) and the hatchery Piscicultura Marina Mediterranea, S.L. (Burriana, Castellon, Spain). It was financed by JACUMAR (the PROGENSA project) and the Spanish Ministry of Science and Innovation (MICINN; National Program of Resources and Food and Agriculture Technologies, AGL2006-13411-C03-00, SELECTSPARUS, and AGL2007-64040-C03-00, SELECTBREAM, including European Regional Development Funds). V. Gallego was supported by a FPI scholarship financed by MICINN; C. Garcia-Fernandez was supported by a FPU scholarship financed by MICINN; and I. Mazzeo was supported by a FPI scholarship financed by Generalitat Valenciana. We are indebted to three anonymous referees and the journal editor for valuable comments.

STUDY DESIGN A prospective, randomized, controlled, multicenter clinical study. OBJECTIVE To evaluate the safety and feasibility of osteogenic protein (OP)-1 in 1-level lumbar spine instrumented posterolateral fusions. SUMMARY OF BACKGROUND DATA Instrumented posterolateral fusion with the use of autograft is a commonly performed procedure for a variety of spinal disorders. However, harvesting of bone from the iliac crest is associated with complications. A promising alternative for autograft are bone morphogenetic proteins. METHODS As part of a larger prospective, randomized, multicenter study, 36 patients were included, who received a 1-level instrumented posterolateral fusion of the lumbar spine. All patients had a degenerative or isthmic spondylolisthesis with symptoms of neurologic compression. There were 2 treatment arms: OP-1 combined with locally available bone from laminectomy (OP-1 group) or iliac crest autograft (autograft group). The primary outcome was the fusion rate based on a computed tomography scan after 1-year follow-up. The clinical outcome was measured using the Oswestry Disability Index. Additionally, the safety of OP-1 was evaluated by comparing the number and severity of adverse events that occurred between both groups. RESULTS Using strict criteria, fusion rates of 63% were found in the OP-1 group and 67% in the control group (P = 0.95). There was a decrease in Oswestry scores at subsequent postoperative time points compared with preoperative values (P > 0.001). There were no significant differences in the mean Oswestry scores between the study group and control group at any time point (P = 0.56). No product-related adverse events occurred. CONCLUSION The results demonstrate that OP-1 combined with locally obtained autograft is a safe and effective alternative for iliac crest autograft in instrumented single-level posterolateral fusions of the lumbar spine. The main advantage of OP-1 is that it avoids morbidity associated with the harvesting of autogenous bone grafts from the iliac crest.

Transferrin (Tf) is a multi-function protein with a central role in iron metabolism, and it is this function that is associated with a role in the innate immune system response. The clear link between Tf and immune defense mechanism lead to propose Tf as a candidate gene for disease resistance. In this study, genomic and cDNA sequences of Tf gene in gilthead seabream (Sparus aurata L.) (SaTf gene), were identified and characterized. SaTf gene structure consists of a coding region of 2076 nucleotides divided into 17 exons and a no-coding region that includes 16 introns and spans 5495 nucleotides. The deduced Tf protein for gilthead seabream is composed of 691 amino acids and consists of an initial peptide and two lobes (N- and C-lobes). This gene structure is similar to that of previously described Tf genes in other fish species. RT-PCR analyses carried out in different tissues and two developmental stages showed tissue-and stage-specific Tf expression in gilthead seabream. Finally, by sequencing the transferrin genomic sequences of 20 unrelated seabreams, 31 SNPs were identified. These data allowed the estimation of the frequency of nucleotide substitution in the SaTf gene as 1SNP per 253 bp. SNPs were detected in different regions of the genomic sequence but they were mainly localized in non-coding regions, specifically, SNP frequency in non-coding regions was fifteen-fold higher than within coding regions.

Purpose To use immunohistochemical techniques to identify and localize the structural macromolecules of the extracellular matrix (ECM) of the normal adult equine lamina cribrosa in order to make comparisons to the extracellular matrix of the lamina cribrosa of horses with glaucoma. Methods Normal eyes of five adult horses between 5 and 10 years of age were fixed in 10% neutral buffered formalin and embedded in paraffin. Polyclonal rabbit-derived antibodies against human elastin, laminin, fibrillin-1, and collagen types I, III and IV, and polyclonal goat-derived antibodies against collagen type VI were used as primary antibodies. Transverse and longitudinal histologic sections of the optic nerve head and lamina cribrosa were stained using several dilutions of the primary antibodies, biotinylated link antibody, horseradish peroxidase-labeled streptavidin, and 3,3′-diaminobenzidine as a chromogen. The immunohistochemical staining patterns were qualitatively interpreted. Results The normal adult horse lamina cribrosa labeled positively for collagen types I, III and VI, laminin, elastin and fibrillin. Collagen type VI staining of the laminar ECM was most intense, followed by labeling for collagen types III and I, respectively. Laminar blood vessels were weakly positive for laminin and slightly positive for type IV collagen. The scleral ECM of the laminar insertion zone had more intense labeling for collagen types I and VI than did the laminar plates. Conclusions The extracellular matrix of the laminar plates of the adult equine lamina cribrosa is similar to the dog as it consists of elastic and collagen fibers (with collagen types VI, III and I). Both the normal dog and horse lamina display more intense staining of collagen type VI than is found in the ECM of the normal human lamina cribrosa. The macromolecular structure of the equine lamina cribrosa suggests that it is a very resilient structure that may provide some protection to the optic nerve axons during episodes of elevated intraocular pressure.

A retrospective study is presented of 14 patients with pathologic fractures of the humerus (12 established, two impending) treated with Seidel nailing from 1988 through 1995 in the authors' institution. There were nine women and five men whose average age was 59.5 years. Breast, prostate, and kidney hypernephroma accounted for the majority of the primary lesions. All but one lesion were located in the middle shaft of the humerus. Ten lesions were considered large (> 5 cm long). In five cases an open curettage and allografting were done. Early pain relief was successful in 85% of the patients. The worst complication found was definite nerve palsy in two (14.28%) patients. Ten fractures healed and two failed to heal. Two thirds of the patients had good functional results. The average survival was 12 months. Intramedullary fixation of pathologic fractures improves the quality of life by controlling pain for most patients.

IN previous papers1–4 we showed that different metabolites, both in vivo and in vitro, produce insulin secretion which we measured by the method of the epididymal fat of the rat. In view of some of these results we decided to ascertain whether the intravenous injection of ATP was a stimulant to insulin secretion; although we are aware that the point of view actually held is that the metabolic processes affected by this nucleotide are intracellular.