Time-lapsed graphene moir\'e superlattice on Cu(111)

The detailed study of the graphene (gr) moir\'e superlattices emerging due to the mismatch between the substrate's and gr-overlayer crystal lattices is inevitable because of its high technological relevance. However, little is known about the dynamics of moir\'e superstructures on gr. Here, we report the first classical molecular dynamics simulation (CMD) of the moir\'e superlattice of graphene on Cu(111) using a new parameterized Tersoff-potential for the graphene/Cu(111) interface fitted in this paper to nonlocal van der Waals density functional theory (DFT) calculations. The interfacial force field with time-lapsed CMD provides superlattices in good quantitative agreement with the available experimental results. The long range coincidence supercells of $2 \times 2$ and $3 \times 3$ with nonequivalent moir\'e hills have also been identified and analyzed. The moir\'e superlattice exhibits a pattern which is dynamical rather than statically pinned to the support and can be observed mostly via time lapsing. The instantaneous snapshots of the periodic moir\'e pattern already at low temperature are weakly disordered lacking the apparent sharpness of the time averaged pattern and scanning tunneling microscopy images. This suggests the existence of competing orders between a static (1st order) and a dynamical (2nd order) moir\'e superstructures.The revealed random height fluctuations may limit the important electronic properties of supported graphene such as the mobility of charge carriers.Comment: 14 pages, 8 figures, supplementary material included. arXiv admin note: text overlap with arXiv:1401.171

Rotation misorientated graphene moire superlattices on Cu(111): classical molecular dynamics simulations and scanning tunneling microscopy studies

Graphene on copper is a system of high technological relevance, as Cu is one of the most widely used substrates for the CVD growth of graphene. However, very little is known about the details of their interaction. One approach to gain such information is studying the superlattices emerging due to the mismatch of the two crystal lattices. However, graphene on copper is a low-corrugated system making both their experimental and theoretical study highly challenging. Here, we report the observation of a new rotational Moire superlattice of CVD graphene on Cu (111), characterized by a periodicity of $1.5 \pm 0.05$ nm and corrugation of $0.15 \pm 0.05$ $\hbox{\AA}$ , as measured by Scanning Tunneling Microscopy. To understand the observed superlattice we have developed a newly parameterized Tersoff-potential for the graphene/Cu (111) interface fitted to nonlocal van der Waals density functional theory (DFT) calculations. The interfacial force field with time-lapsed CMD provides superlattices in good quantitative agreement with the experimental results, for a misorientation angle of $10.4 \pm 0.5,^{\circ}$ without any further parameter adjustment. Furthermore, the CMD simulations predict the existence of two non-equivalent high-symmetry directions of the Moir\'e pattern that could also be identified in the experimental STM images.Comment: 7 pages, 2 figures, 2 table

The classical molecular dynamics simulation of graphene on Ru(0001) using a fitted Tersoff interface potential

The accurate molecular dynamics simulation of weakly bound adhesive complexes, such as supported graphene, is challenging due to the lack of an adequate interface potential. Instead of the widely used Lennard-Jones potential for weak and long-range interactions we use a newly parameterized Tersoff-potential for graphene/Ru(0001) system. The new interfacial force field provides adequate moir$\acute{e}$ superstructures in accordance with scanning tunnelling microscopy images and with DFT results. In particular, the corrugation of $\xi \approx 1.0 \pm 0.2$ $\hbox{\AA}$ is found which is somewhat smaller than found by DFT approaches ($\xi \approx 1.2$ $\hbox{\AA}$) and is close to STM measurements ($\xi \approx 0.8 \pm 0.3$ $\hbox{\AA}$).The new potential could open the way towards large scale simulations of supported graphene with adequate moir$\acute{e}$ supercells in many fields of graphene research. Moreover, the new interface potential might provide a new strategy in general for getting accurate interaction potentials for weakly bound adhesion in large scale systems in which atomic dynamics is inaccessible yet by accurate DFT calculations.Comment: 7 pages, 3 figures, 2 tables, + supplementary materia

Effect of hair shearing on live performance and carcass traits of growing rabbits under hot ambient temperature

[EN] The aim of the study was to examine the effect of hair shearing in growing rabbits reared at high ambient temperature. The live performance and carcass traits of growing rabbits reared at 20°C (not sheared, C, n=50) or at 28°C (not sheared, H, n=50, or sheared at 5, 7 and 9 wk, HS, n=50) were compared. The ambient temperature and relative humidity were 20.5±1.1°C and 54±11% in the 20°C room and 28.8±0.2°C and 35±8% in 28°C room, respectively. Feed intake of H and HS groups decreased by 29.0 and 20.4%, respectively, compared to C rabbits (P<0.001). The same data for weight gain were 24.6 and 16.9% (P<0.001), and for body weight at 12 wk were 16.8 and 11.5% (P<0.001). At the same time, the feed conversion ratio improved (C: 3.53, HS: 3.34, H: 3.31; P<0.001). Nevertheless, the mortality rate of rabbits was not affected by the studied treatment and was overall low (0-4%). No differences were observed in dressing out percentages either (ratio of chilled carcass (CC) to the slaughter weight: 61.6-61.9%). The ratio of liver to CC differed among the experimental groups, with the highest value recorded in C group and the lowest in H group; HS rabbits showed intermediate results (C: 4.86%, HS: 4.27%, H: 3.91%; P<0.001). Lower ratios of fat deposits to reference carcass were also observed in rabbits kept at high ambient temperature (perirenal fat: C: 2.59%, HS: 1.82%, H: 1.60%; P<0.001; scapular fat: C: 0.89%, HS: 0.66%, H: 0.51%; P<0.001). It can be concluded that the negative effect of higher ambient temperature (28 vs. 20°C) on production in growing rabbits can be reduced significantly by hair shearing.En este agradecimieento: "The work was supported by the GINOP-2.3.4-15-2016-00005 project. Publication was supported by the EFOP-3.6.3-VEKOP-16–2017–00008 project. The project is co-funded by the European Union and the European Social Fund"Matics, Z.; Kasza, R.; Gerencsér, Z.; Radnai, I.; Dalle Zotte, A.; Cullere, M.; Szendrő, Z. (2020). Effect of hair shearing on live performance and carcass traits of growing rabbits under hot ambient temperature. World Rabbit Science. 28(3):161-167. https://doi.org/10.4995/wrs.2020.13164OJS161167283Balnave D. 1972. The effect of temperature and length of exposure on liver composition and hepatic lipogenic enzyme activity in the immature male chick (Gallus domesticus). Comp. Biochem. Physiol., 438: 999-1007. https://doi.org/10.1016/0305-0491(72)90244-1Blasco A., Ouhayoun J. 1996. Harmonization of criteria and terminology in rabbit meat research. Revised proposal. World Rabbit Sci., 4: 93-99. https://doi.org/10.4995/wrs.1996.278Chiericato G.M., Rizzi C., Rostellato V. 1993. Effect of genotype and environmental temperature on performance of the young meat rabbit. World Rabbit Sci., 1: 119-125. https://doi.org/10.4995/wrs.1993.204Chiericato G.M., Ravarotto L., Rizzi R. 1994. Study of the metabolic profile of rabbits in relation to two different environmental temperatures. World Rabbit Sci., 2: 153-160. https://doi.org/10.4995/wrs.1994.232Chiericato G.M., Rizzi C., Rostellato V. 1996. Growth and slaughtering performance of three rabbit genotypes under different environmental conditions. Ann. Zootech., 45: 311-318. https://doi.org/10.1051/animres:19960403Deltoro J., López A.M. 1986. Development of commercial characteristics of rabbit carcasses during growth. Livest. Prod. Sci., 15: 271-283. https://doi.org/10.1016/0301-6226(86)90034-5EC 2010. Directive 2010/63/EU of the European Parliament and of the Council of 22 September 2010 on the protection of animals used for scientific purposes. Official Journal of the European Union L276: 33-79.Fernández-Carmona J., Cervera C., Sabater C., Blas E. 1995. Effect of diet composition on the production of rabbit breeding does housed in a traditional building and at 30°C. Anim. Feed Sci. Technol., 52: 289-297. https://doi.org/10.1016/0377-8401(94)00715-LFinzi A., Morera P., Kuzminsky G. 1992. Effect of shearing on rabbit bucks performances in hot ambient conditions. J. Appl. Rabbit Res., 15: 489-494.Fuquay J.W. 1981. Heat stress as it affects animal production. J. Anim. Sci., 52: 164-174. https://doi.org/10.2527/jas1981.521164xHermes I.H., Ahmed B.M., Khalil M.H., Salah M.S., Al-Homidan A.A. 1999. Growth performance, nutrients utilization and carcass traits of growing Californian rabbits raised under different ambient temperatures. Egypt. J. Rabbit Sci., 9: 117-138.Jackson R., Rogers A.D, Lukefahr S.D. 2006. Effects of the naked gene on postweaning performance and thermotolerance characters in fryer rabbits: Final results. World Rabbit Sci., 14: 147-155. https://doi.org/10.4995/wrs.2006.559Kovitvadhi A., Chundang P., Thongprajukaew K., Tirawattanawanich C. 2019. Effects of different ambient temperatures on growth performances, digestibility, carcass traits and meat chemical components in fattening rabbits. J. Agriculture, 35: 495-502.Lebas F., Ouhayoun J. 1987. Incidence du niveau protéique de l'aliment, de milieu d'élevage et de la saison sur la croissance et les qualités bouchéres du lapin. Ann. Zootech., 36: 421-432. https://doi.org/10.1051/animres:19870406Lebas F., Coudert P., de Rochambeau H., Thébault R.G. 1997. The rabbit: husbandry, health and production. FAO Anim. Prod. and Health Series No. 21Lukefahr S.D., Ruiz-Feria C.A. 2003. Rabbit growth performance in a subtropical and semi-arid environment: Effects of fur clipping, ear length, and body temperature. Livest. Res. Rural Devel. 15: 2. Available at http://www.cipav.org.co/lrrd/lrrd15/2/luke152.htm Accessed October 2019.Marai I.F.M., Habeeb A.A.M., Gad A.E. 2002. Rabbits' productive, reproductive and physiological performance traits as affected by heat stress: a review. Livest. Prod. Sci., 78: 71-90. https://doi.org/10.1016/S0301-6226(02)00091-XMaya-Soriano M.J., Taberner E., Sabes-Alsina M., Ramon J., Rafel O., Tusell L., Piles M., López-Béjar M. 2015. Daily exposure to summer temperatures affects the motile subpopulation structure of epididymal sperm cells but not male fertility in an in vivo rabbit model. Theriogenology, 84: 384-389. https://doi.org/10.1016/j.theriogenology.2015.03.033Metzger Sz. 2006. Examination on carcass traits and meat quality of rabbit. (in Hung.) Doctoral (Ph.D.) dissertation. pp. 135.NASA https://climate.nasa.gov/Perez J.M., Lebas F., Gidenne T., Maertens L., Xiccato G., Parigi-Bini R., Dalle Zotte A., Cossu M.E., Carazzolo A., Villamide M.J., Carabaño R., Fraga M.J., Ramos M.A., Cervera C., Blas E., Fernández J., Falcão-e-Cunha L., Bengala Freire J. 1995. European reference method for in vivo determination of diet digestibility in rabbits. World Rabbit Sci. 3: 41-43. https://doi.org/10.4995/wrs.1995.239Renaudeau D., Collin A., Yahav S., de Basilio V., Gourdine J.L., Collier R.J. 2012. Adaptation to hot climate and strategies to alleviate heat stress in livestock production. Animal, 6: 707-728. https://doi.org/10.1017/S1751731111002448SAS Version 9.4. 2014. SAS Institute Inc; Cary, NC. Schlolaut W. 1995. Das grosse Buch vom Kaninchen. DLG-Verlag, Frankfurt am Main.Stephan E. 1980. The influence of environmental temperatures on meat rabbits of different breeds. Commercial Rabbit, 8: 12-15.Szendrő Zs., Rashwan R.R., Biró-Németh E., Radnai I., Orova Z. 2007. Effect of shearing of hair in summer on production of rabbit does. Acta Agr. Kapos., 11: 37-42.Szendrő Zs., Papp Z., Kustos K. 2018. Effect of ambient temperature and restricted feeding on the production of rabbit does and their kits. Acta Agr. Kapos., 22: 1-17. https://doi.org/10.31914/aak.2272Verga M., Luzi F., Carenzi C., 2007. Effects of husbandry and management systems on physiology and behaviour of farmed and laboratory rabbits. Horm. Behav., 52, 122-129. https://doi.org/10.1016/j.yhbeh.2007.03.024Zeferino P.C., Moura T.M.A.S.A., Fernandes S., Kanayama S.J., Scapinello C., Sartori R.J. 2011. Genetic group × ambient temperature interaction effects on physiological responses and growth performance of rabbits. Livest. Sci., 140: 177-183. https://doi.org/10.1016/j.livsci.2011.03.02

EFFECTS OF DIVERGENT SELECTION FOR HIND LEG MUSCLE VOLUME ON ITS LIPID PEROXIDE AND GLUTATHIONE REDOX STATUS, AND FATTY ACID COMPOSITION IN GROWING RABBITS

ABSTRACT: Pannon White bucks were selected divergently using CT method by the volume of the hind leg muscle. Animals showed the highest and lowest muscle volumes were selected as minus and plus-selected variants. The male progenies of the minus and plus-selected parents were slaughtered as fi rst generation which was selected again by CT method and the male progenies of the parents were slaughtered. Results in the fi rst and second generation suggest that selection, as a genetic effect did not affect the rate of lipid peroxidation, as was measured by malondialdehyde content and glutathione redox status, as was measured by the reduced glutathione content and glutathione peroxidase activity of the hind leg muscle. However, there were some differences in the fatty acid composition. Signifi cant (P<0.05) difference was found in palmitoleic acid content which was higher in the minus as compared to the plus variants in the second generation, in eicosadienoic acid which was higher in the fi rst as compared to the second generation of minus variants, and total monounsaturated fatty acids which was higher in the minus as compared to the plus variants in the second generation. It means that selection for higher hind leg volume would not causes marked in changes in the rabbit meat quality as measured by lipid peroxide and glutathione status as well as fatty acid composition

Dietary supplementation of Digestarom® herbal formulation: effect on apparent digestibility, faecal and caecal microbial counts and live performance of growing rabbits

[EN] The experiment aimed to study the effect of Digestarom® dietary inclusion (herbal formulation containing a mixture of essential oils, herbs, spices and extracts) on apparent digestibility and digestive ecosystem of growing rabbits, as well as the effects of its supplementation before and after weaning on growth performance. At kindling, rabbit does and litters were divided into 2 dietary groups (51 does/group) and fed either a control diet (C) or a diet supplemented with 300 mg Digestarom®/kg diet (D) until weaning, which occurred at 35 d (before weaning supplementation). Each group was further divided into 3 dietary groups: CC received the control diet and DD received the D diet from 5 to 12 wk of age, and DC were fed with D (from 5 to 8 wk of age) and C diets (from 8 to 12 wk of age) (after weaning supplementation; 54 kits/group). An in vivo digestibility trial and a faecal microbial count were carried out on growing rabbits that received only the C or D diets during the trial. The C group showed higher DM intake than D group (215 vs. 196 g/d; P<0.05). The faecal digestibility of ether extract (75.9 vs. 59.8%; P<0.001), cellulose (25.9 vs. 20.6%; P<0.05) and gross energy (51.8 vs. 49.1%; P<0.05) was higher for C than for D group, whereas that of starch (98.9 vs. 98.8%; P<0.001) and the digestible protein to digestible energy ratio (13.9 vs. 13.2 g digestible protein/MJ digestible energy; P<0.01) was the highest for rabbits fed D diet. Stomach and caecal pH, caecal and faecal microbial counts were independent of the dietary treatment. The only exception was the stomach pH in 8 wk-old rabbits, which had the lowest value in C rabbits (P<0.05). The D supplementation before weaning improved feed conversion ratio throughout the growing phase (4.3 vs. 4.4 for D and C, respectively; P<0.05), whereas significant differences in daily weight gain, feed conversion ratio and mortality were observed only in the first period after weaning. Based on the results obtained, dietary supplementation with Digestarom® does not seem to confirm the positive results previously reported for growing rabbits.Celia, C.; Cullere, M.; Gerencsér, Z.; Matics, Z.; Giaccone, V.; Kovács, M.; Bónai, A.... (2016). Dietary supplementation of Digestarom® herbal formulation: effect on apparent digestibility, faecal and caecal microbial counts and live performance of growing rabbits. World Rabbit Science. 24(2):129-138. doi:10.4995/wrs.2016.406912913824

Carcass traits and meat quality of growing rabbits in pens with and without different multilevel platforms

[EN] The aim of this trial was to determine the effect of the presence of wire or plastic mesh elevated platforms on carcass traits and meat quality characteristics, with particular attention to the oxidative status of growing rabbits. A total of 174 five-week old rabbits were randomly divided into 3 groups with 2 replications (6 pens; 29 rabbits/pen): pens without platforms (NoP) with a stocking density of 16 rabbits/m2 and pens with wire-mesh platforms (WP) or plastic-mesh platforms (PP) that were placed on 2 levels, with a stocking density of 16 rabbits/m2 on the floor or 9.14 rabbits/m2 when the platform were included. At 84 d rabbits were slaughtered. The slaughter traits and Longissimus lumborum (LL) physical and chemical compositition were not affected by treatments. Rabbits from the PP group showed the highest retinol and γ-tocotrienol content on LL muscle, whereas the NoP ones showed a higher α-tocotrienol and α-tocopherol level. The absence of platforms led to decreased (P<0.001) thiobarbituric acid-reactive substances values and induced an improvement in n-3 polyunsaturated fatty acids. Levels of linoleic, linolenic and docosahexaenoic acids were equal to those of the WP group (23.45, 3.75, 0.64% in NoP and 22.6, 4.14, 0.53% in WP, respectively) but higher than in PP rabbits (20.86, 3.05, 0.45%, respectively). It can be concluded that the pens with elevated platforms provide greater possibilities for movement, which is beneficial from the viewpoint of animal welfare. However, this greater activity influences the oxidative status of the meat, decreasing the antioxidant content and worsening the lipid oxidation of rabbit meat.This research was supported by the GOP-1.3.1-11/B-2011-0045 project and by the János Bolyai Research Scholarship (BO/00373/14/4) of the Hungarian Academy of Sciences.138Martino, M.; Mattioli, S.; Farkas, P.; Szendrő, Z.; Dal Bosco, A.; Ruggeri, S.; Matics, Z.... (2016). Carcass traits and meat quality of growing rabbits in pens with and without different multilevel platforms. World Rabbit Science. 24(2). https://doi.org/10.4995/wrs.2016.392212924

Effect of different weaning age (21, 28 or 35 days) on production, growth and certain parameters of the digestive tract in rabbits

The effect of different weaning ages, that is, 21 (G21), 28 (G28) or 35 (G35) days, on growth and certain parameters of the digestive tract was examined in rabbits to assess the risk of early weaning attributable to the less-developed digestive system. On days 35 and 42, G35 rabbits had 10% to 14% and 10% higher BW, respectively ( P,0.05), than those weaned at days 21 and 28. In the 4th week of life, early weaned animals had 75% higher feed intake than G28 and G35 rabbits ( P,0.05). The relative weight of the liver increased by 62% between 21 and 28 days of age, and thereafter it decreased by 76% between 35 and 42 days of age ( P,0.05), with G21 rabbits having 29% higher weight compared with G35 animals on day 35 ( P,0.05). The relative weight of the whole gastrointestinal (GI) tract increased by 49% and 22% after weaning in G21 and G28 rabbits, respectively ( P,0.05). On day 28, the relative weight of the GI tract was 19% higher in G21 than in G28 rabbits, whereas on day 35 G21 and G28 animals had a 12% heavier GI tract compared with G35 rabbits ( P,0.05). Age influenced the ratio of stomach, small intestine and caecum within the GI tract; however, no effect of different weaning age was demonstrated. The pH value of the stomach and caecum decreased from 5.7 to 1.6 and from 7.1 to 6.3, respectively, whereas that of the small intestine increased from 6.8 to 8.4 ( P,0.05); the differences between groups were not statistically significant. Strictly anaerobic culturable bacteria were present in the caecum in high amounts (108), already at 14 days of age; no significant difference attributable to weaning age was demonstrable. The concentration of total volatile fatty acids (tVFA) was higher in G21 than in G28 and G35 throughout the experimental period ( P,0.05). The proportion of acetic and butyric acid within tVFA increased, whereas that of propionic acid decreased, resulting in a C3 : C4 ratio decreasing with age. Early weaning (G21) resulted in higher butyric acid and lower propionic acid proportions on day 28 ( P,0.05). No interaction between age and treatment was found, except in relative weight of the GI tract and caecal content. In conclusion, early weaning did not cause considerable changes in the digestive physiological parameters measured, but it resulted in 10% lower growth in rabbits