Prifysgol Bangor

  1. Erthygl › Ymchwil › Adolygwyd gan gymheiriaid
  2. Cyhoeddwyd

    Low molecular weight organic acid adsorption in forest soils: effects on soil solution concentrations and biodegradation rates.

    Van Hees, P. A., Vinogradoff, S. I., Edwards, A. C., Godbold, D. L. & Jones, D. L., 1 Awst 2003, Yn: Soil Biology and Biochemistry. 35, 8, t. 1015-1026

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  3. Cyhoeddwyd

    Low repopulation of poor districts in New Orleans proves little.

    Hockley, N., 15 Medi 2010, Yn: Nature. 467, 7313, t. 271

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  4. Cyhoeddwyd

    Low temperature bioremediation of oil-contaminated soil using biostimulation and bioaugmentation with a Pseudomonas sp from maritime Antarctica.

    Stallwood, B., Shears, J., Williams, P. A. & Hughes, K. A., 1 Hyd 2005, Yn: Journal of Applied Microbiology. 99, 4, t. 794-802

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  5. Cyhoeddwyd

    Low temperature induced systems failure in Escherichia coli: Insights from rescue by cold-adapted chaperones.

    Golyshin, P., Strocchi, M., Ferrer, M., Timmis, K. N. & Golyshin, P. N., 1 Ion 2006, Yn: Proteomics. 6, 1, t. 193-206

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  6. Cyhoeddwyd

    Low temperature sintering of binder-containing TiO2/metal peroxide pastes for dye-sensitized solar cells

    Al Husenawi, D. K., Holliman, P. J., Muslem, D. K., Jones, E. W., Connell, A., Davies, M. L., Charbonneau, C., Carnie, M. J. & Worsley, D. A., 2 Mai 2014, Yn: Journal of Materials Chemistry A. 29, 2, t. 11134-11143

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  7. Cyhoeddwyd

    Low thermal sensitivity grating devices based on ex-45° tilting structure capable of forward-propagating cladding modes coupling

    Zhou, K., Zhang, L., Chen, X. & Bennion, I., Rhag 2006, Yn: Journal of Lightwave Technology. 24, 12, t. 5087-5094

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  8. Cyhoeddwyd

    Low threshold gain metal coated laser nanoresonators

    Mizrahi, A., Lomakin, V., Slutsky, B. A., Nezhad, M. P., Feng, L. & Fainman, Y., 1 Meh 2008, Yn: Optics Letters. 33, 11, t. 1261-1263 3 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  9. Cyhoeddwyd

    Low-Intensity Guided Help Through Mindfulness (LIGHTMIND): study protocol for a randomised controlled trial comparing supported mindfulness-based cognitive therapy self-help to supported cognitive behavioural therapy self-help for adults experiencing depression.

    Strauss, C., Arbon, A., Barkham, M., Byford, S., Crane, R., de Visser, R., Heslin, M., Jones, A-M., Jones, F., Lea, L., Parry, G., Rosten, C. & Cavanagh, K., 4 Mai 2020, Yn: Trials. 21, 1, 374.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  10. Cyhoeddwyd

    Low-complexity modulation format identification based on am- 2 plitude histogram distributions for digital coherent receivers

    Hao, M., Jiang, X., Xiong, X., Giddings, R., He, W. & Tang, J., 20 Ebr 2023, Yn: Photonics.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  11. Cyhoeddwyd

    Low-threshold organic laser based on an oligofluorene truxene with low optical losses.

    Tsiminis, G., Wang, Y., Shaw, P. E., Kanibolotsky, A. L., Perepichka, I. F., Dawson, M. D., Skabara, P. J., Turnbull, G. A. & Samuel, I. D., 15 Meh 2009, Yn: Applied Physics Letters. 94, 24, t. 243304

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  12. Cyhoeddwyd

    Lower left temporal-frontal connectivity characterizes expert and accurate performance: High-alpha T7-Fz connectivity as a marker of conscious processing during movement

    Gallicchio, G., Cooke, A. & Ring, C., Chwef 2016, Yn: Sport, Exercise, and Performance Psychology. 5, 1, t. 14-24

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  13. Cyhoeddwyd

    Low‐cost tools mitigate climate change during reproduction in an endangered marine ectotherm

    Clarke, L., Elliot, R. L., Abella-Perez, E., Jenkins, S., Marco, A. & Hawkes, L. A., 1 Gorff 2021, Yn: Journal of Applied Ecology. 58, 7, t. 1466-1476

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  14. Cyhoeddwyd

    Lumen pressure within obliquely insonated absorbent solid cylindrical shells with application to Doppler flow phantoms.

    Fish, P., Steel, R. & Fish, P. J., 1 Chwef 2002, Yn: IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control. 49, 2, t. 271-280

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  15. Cyhoeddwyd

    Lunacy and the 'Islands in the British Seas'.

    Hirst, J. D. & Hirst, D., 1 Rhag 2007, Yn: History of Psychiatry. 18, 4, t. 411-433

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  16. Cyhoeddwyd

    Lutispora saccharofermentans sp. nov., a mesophilic, non-spore-forming bacterium isolated from a lab-scale methanogenic landfill bioreactor digesting anaerobic sludge, and emendation of the genus Lutispora to include species which are non-spore-forming and mesophilic

    El Houari, A., Carpenter, M., Chaplin, D., Golyshin, P. & McDonald, J. E., Chwef 2023, Yn: International Journal of Systematic Evolutionary Microbiology. 73, 1, 005683.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  17. Cyhoeddwyd

    Lymphoedema and chronic oedema in an aging population

    Jones, J., 3 Ion 2015, Yn: Nursing and Residential Care. 17, 1, t. 26-29 4 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  18. Cyhoeddwyd

    Lymphoedema and chronic oedema: what's the difference?

    Jones, J., 1 Rhag 2014, Yn: Nursing and Residential Care. 16, 12, t. 684-686 3 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  19. Cyhoeddwyd

    Lyra-viol Ecclesiastica: A neglected manuscript source in Archbishop Marsh’s Library, Dublin

    Cunningham, J., 2009, Yn: The Viola da Gamba Society Journal. 3, t. 1-54 54 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  20. Cyhoeddwyd

    L’Islam et l’humour: un rire communautaire ou un rire universel?

    Ervine, J., 31 Mai 2017, Yn: Le Temps des médias. 28, t. 144-157

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  21. Cyhoeddwyd

    L’immagine del turista in Avventure in Africa di Gianni Celati.

    Rorato, L., 1 Ion 2007, Yn: Italica. 84, t. 262-273

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  22. Cyhoeddwyd

    MEDEX 2015: Heart Rate Variability Predicts Development of Acute Mountain Sickness

    Sunderland, A., Freer, J., Evans, L., Dolci, A., Crotti, M. & Macdonald, J., 1 Medi 2017, Yn: High Altitude Medicine and Biology. 18, 3, t. 199-208

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  23. Cyhoeddwyd

    MEDEX 2015: Prophylactic effects of positive expiratory pressure in trekkers at very high altitude.

    Rupp, T., Maufrais, C., Walther, G., Esteve, F., Macdonald, J., Bouzat, P. & Verges, S., 21 Medi 2021, Yn: Frontiers in Physiology. 12, 710622.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  24. Cyhoeddwyd

    MEDEX2015: Greater sea-level fitness is associated with lower sense of effort during Himalayan trekking without worse Acute Mountain Sickness

    Rossetti, G., Macdonald, J., Smith, M., Jackson, A., Callender, N., Newcombe, H. K., Storey, H., Willis, S., van den Beukel, J., Woodward, J., Pollard, J., Wood, B., Newton, V., Virian, J., Haswell, O. & Oliver, S., 1 Meh 2017, Yn: High Altitude Medicine and Biology. 18, 2, t. 152-162

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  25. Cyhoeddwyd

    MHC adaptice divergence between closely related and sympatric african cichlids.

    Blais, J., Rico, C., Van Oosterhout, C., Cable, J., Turner, G. F. & Bernatchez, L., 15 Awst 2007, Yn: PLoS ONE. 2, 8, t. e734

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  26. Cyhoeddwyd

    MIMO generalized predictive control for a hydroelectric power station.

    Jones, D. I., Munoz-Hernandez, G. A. & Jones, D., 1 Ion 2006, Yn: IEEE Transactions on Energy Conversion. 21, 4, t. 921-929

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  27. Cyhoeddwyd

    MIR and NIR nonlinear optical processing using intersubband x(3) in triple quantum well structures.

    Banerjee, S. & Shore, K. A., 1 Gorff 2003, Yn: Semiconductor Science and Technology. 18, 7, t. 655-660

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  28. Cyhoeddwyd

    MOCVD of highly conductive CdO thin films.

    Ellis, D. M. & Irvine, S. J., 1 Meh 2004, Yn: Journal of Materials Science: Materials in Electronics. 15, 6, t. 369-372

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  29. Cyhoeddwyd

    MODELLING THE EFFECTS OF GLOBAL TEMPERATURE INCREASE ON THE GROWTH OF SALT MARSH PLANTS

    Couto, T., Martins, I., Duarte, B. & Cacador, I., 1 Awst 2014, Yn: Applied Ecology and Environmental Research. 12, 3, t. 753-764

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  30. Cyhoeddwyd

    MRNIP is a replication fork protection factor

    Bennett, L., Wilkie, A., Antonopoulou, E., Ceppi, I., Sanchez, A., Vernon, E., Gamble, A., Myers, K. N., Collis, S. J., Cejka, P. & Staples, C., 10 Gorff 2020, Yn: Science Advances. 6, 28, 10 t., eaba5974.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  31. Cyhoeddwyd

    MRNIP/C5orf45 Interacts with the MRN Complex and Contributes to the DNA Damage Response

    Staples, C. J., Barone, G., Myers, K. N., Ganesh, A., Gibbs-Seymour, I., Patil, A. A., Beveridge, R. D., Daye, C., Beniston, R., Maslen, S., Ahel, I., Skehel, J. M. & Collis, S. J., 6 Medi 2016, Yn: Cell. 16, 10, t. 2565-75 11 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  32. Cyhoeddwyd

    Machine bundles woodfuel bales from the residue of clear-fell sites

    Walmsley, J. D., 1 Ion 2007, Yn: Gwlad. 61, t. 15

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  33. Cyhoeddwyd

    Machine learning for ecosystem services

    Willcock, S., Martinez-Lopez, J., Hooftman, D., Bagstad, K., Balbi, S., Marzo, A., Prato, C., Sciandrello, S., Signorello, G., Voigt, B., Villa, F., Bullock, J. & Athanasiadis, I., Hyd 2018, Yn: Ecosystem Services. 33 pt B, t. 165-174 19 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  34. Cyhoeddwyd

    Machine learning in marine ecology an overview of techniques and applications

    Rubbens, P., Brodie, S., Cordier, T., Destro Barcellos, D., Devos, P., A Fernandes-Salvador, J., I Fincham, J., Gomes, A., Olav Handegard, N., Howell, K. L., Jamet, C., Heldal Kartveit, K., Moustahfid, H., Parcerisas, C., Politikos, D., Sauzède, R., Sokolova, M., Uusitalo, L., Van den Bulcke, L., TM van Helmond, A., T Watson, J., Welch, H., Beltran-Perez, O., Chaffron, S., S Greenberg, D., Kühn, B., Kiko, R., Lo, M., M Lopes, R., Ove Möller, K., Michaels, W., Pala, A., Romagnan, J-B., Schuchert, P., Seydi, V., Villasante, S., Malde, K. & Irisson, J-O., 1 Medi 2023, Yn: ICES Journal of Marine Science. 80, 7

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  35. Cyhoeddwyd

    Macro- and micro-geographic variation in pantophysin (Panl) allele frequencies in NE Atlantic cod Gadus morhua

    Case, R. A., Hutchinson, W. F., Hauser, L., Van Oosterhout, C. & Carvalho, G. R., 11 Hyd 2005, Yn: Marine Ecology Progress Series. 301, t. 267-278

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  36. Cyhoeddwyd

    Macro- and microplastic accumulation in soil after 32 years of plastic film mulching

    Li, S., Ding, F., Flury, M., Wang, Z., Xu, L., Li, S., Jones, D. L. & Wang, J., 1 Mai 2022, Yn: Environmental Pollution. 300

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  37. Cyhoeddwyd

    Macro-nutrient concentrations in Antarctic pack ice: Overall patterns and overlooked processes

    Fripiat, F., Meiners, K. M., Vancoppenolle, M., Papadimitriou, S., Thomas, D. N., Ackley, S. F., Arrigo, K. R., Carnet, G., Cozzi, S., Delille, B., Dieckmann, G. S., Dunbar, R. B., Fransson, A., Kattner, G., Kennedy, H., Lannuzel, D., Munro, D. R., Nomura, D., Rintala, J-M., Schoemann, V., Stefels, J., Steiner, N. & Tison, J-L., 29 Maw 2017, Yn: Elementa: Science of the Anthropocene. 5

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  38. Cyhoeddwyd

    Macroalgae exhibit diverse responses to human disturbances on coral reefs

    Cannon, S., Donner, S., Liu, A., Gonzalez Espinosa, P., Baird, A., Baum, J., Bauman, A., Beger, M., Benkwitt, C., Birt, M., Chancerelle, Y., Cinner, J., Crane, N., Denis, V., Depczynski, M., Fadli, N., Fenner, D., Fulton, C., Golbuu, Y., Graham, N., Guest, J., Harrison, H., Hobbs, J-P., Hoey, A., Holmes, T., Houk, P., Januchowski-Hartley, F., Jompa, J., Kuo, C-Y., Valentino Limmon, G., Lin, Y., McClanahan, T., Muenzel, D., Paddack, M., Planes, S., Pratchett, M., Radford, B., Reimer, J., Richards, Z., Ross, C., Rulmal Jr., J., Sommer, B., Williams, G. J. & Wilson, S., 1 Meh 2023, Yn: Global Change Biology. 29, 12, t. 3318-3330

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  39. Cyhoeddwyd

    Macroalgal responses to experimental nutrient enrichment in shallow coastal waters: growth, internal nutrient pools, and isotopic signatures.

    Teichberg, M., Fox, S. E., Aguila, C., Olsen, Y. S. & Valiela, I., 25 Medi 2008, Yn: Marine Ecology Progress Series. 368, t. 117-126

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  40. Cyhoeddwyd

    Macrofaunal communities associated with chemosynthetic habitats from the US Atlantic margin: A comparison among depth and habitat types

    Bourque, J. R., Robertson, C. M., Brooke, S. & Demopoulos, A. W. J., Maw 2017, Yn: Deep Sea Research Part II: Topical Studies in Oceanography. 137, t. 42-55

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  41. Cyhoeddwyd

    Macrofaunal patterns and animal–sediment relationships in Uruguayan estuaries and coastal lagoons (Atlantic coast of South America)

    Gimenez, L., Venturini, N., Kandratavicius, N., Hutton, M., Lanfranconi, A., Rodriguez, M., Brugnoli, E. & Muniz, P., 1 Maw 2014, Yn: Journal of Sea Research. 87, t. 46-55

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  42. Cyhoeddwyd

    Macrophage inflammatory protein-1 alpha receptors are present on cells enriched for CD34 expression from patients with chronic myeloid leukemia.

    RC, C., GS, L., PJ, O-L., A, P. & AD, W., 1 Rhag 1995, Yn: Blood. 86, 11, t. 4270-4277

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  43. Cyhoeddwyd

    Macroprudential policy and bank risk

    Altunbas, Y., Binici, M. & Gambacorta, L., 1 Maw 2018, Yn: Journal of International Money and Finance. 81, March, t. 203-220

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  44. Cyhoeddwyd

    Macroscopic 'acid streamer' growths in acidic, metal-rich mine waters in north Wales consist of novel and remarkably simple bacterial communities

    Hallberg, K., Coupland, K., Kimura, S. & Johnson, D. B., 1 Maw 2006, Yn: Applied and Environmental Microbiology. 72, 3, t. 2022-2030

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  45. Cyhoeddwyd

    Macrotidal rip current experiment : circulation and dynamics

    Austin, M. J., Scott, T. M., Brown, J. W., Brown, J. A. & Macmahan, J. H., 2009, Yn: Journal of Coastal Research. 2009, 56, t. 24-28

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  46. Cyhoeddwyd

    Madagascar's extraordinary biodiversity: Evolution, distribution, and use

    Antonelli, A., Smith, R. J., Perrigo, A. L., Crottini, A., Hackel, J., Testo, W., Farooq, H., Torres Jiménez, M. F., Andela, N., Andermann, T., Andriamanohera, A. M., Andriambololonera, S., Bachman, S. P., Bacon, C. D., Baker, W. J., Belluardo, F., Birkinshaw, C., Borrell, J. S., Cable, S., Canales, N. A., Carrillo, J. D., Clegg, R., Clubbe, C., Cooke, R. S. C., Damasco, G., Dhanda, S., Edler, D., Faurby, S., de Lima Ferreira, P., Fisher, B. L., Forest, F., Gardiner, L. M., Goodman, S. M., Grace, O. M., Guedes, T. B., Henniges, M. C., Hill, R., Lehmann, C. E. R., Lowry, P. P., Marline, L., Matos-Maraví, P., Moat, J., Neves, B., Nogueira, M. G. C., Onstein, R. E., Papadopulos, A. S. T., Perez-Escobar, O. A., Phelps, L. N., Phillipson, P. B., Pironon, S., Przelomska, N. A. S., Rabarimanarivo, M., Rabehevitra, D., Raharimampionona, J., Rajaonah, M. T., Rajaonary, F., Rajaovelona, L. R., Rakotoarinivo, M., Rakotoarisoa, A. A., Rakotoarisoa, S. E., Rakotomalala, H. N., Rakotonasolo, F., Ralaiveloarisoa, B. A., Ramirez-Herranz, M., Randriamamonjy, J. E. N., Randriamboavonjy, T., Randrianasolo, V., Rasolohery, A., Ratsifandrihamanana, A. N., Ravololomanana, N., Razafiniary, V., Razanajatovo, H., Razanatsoa, E., Rivers, M., Sayol, F., Silvestro, D., Vorontsova, M. S., Walker, K., Walker, B. E., Wilkin, P., Williams, J., Ziegler, T., Zizka, A. & Ralimanana, H., 2 Rhag 2022, Yn: Science. 378, 6623, eabf0869.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  47. Cyhoeddwyd

    Madness explained: Why we must reject the Kraepelinian paradigm and replace it with a 'complaint-orientated' approach to understanding mental illness.

    Bentall, R. P., 1 Ion 2006, Yn: Medical Hypotheses. 66, 2, t. 220-233

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  48. Cyhoeddwyd

    Mae Kinnock yn ddieuog - yn y bôn.

    Edwards, A. C., 1 Maw 2009, Yn: Barn. 554, t. 17-18

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  49. Cyhoeddwyd

    Mae gennyf gred, mae gennyf gân': Rhai themâu ym marddoniaeth Pennar Davies.

    Morgan, D. D., 1 Gorff 2005, Yn: Llên Cymru. 28, t. 160-177

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  50. Cyhoeddwyd

    Magical ideation and its relation to lateral preference.

    Nicholls, M. E., Orr, C. A. & Lindell, A. K., 1 Tach 2005, Yn: Laterality. 10, 6, t. 503-515

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  51. Cyhoeddwyd

    Magnetic Functionalized Nanoparticles for Biomedical, Drug Delivery and Imaging Applications

    Anderson, S., Gwenin, V. & Gwenin, C., 30 Mai 2019, Yn: Nanoscale Research Letters. 14, 1, 16 t., 188.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid