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Journal articles on the topic 'Spröde'

Author: Grafiati

Published: 4 June 2021

Last updated: 11 February 2022

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1

Scheffels, Gerald. "Ein Werkstoff mit besonderen Eigenschaften." Konstruktion 70, no. 01-02 (2018): IW14—IW16. http://dx.doi.org/10.37544/0720-5953-2018-01-02-68.

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Technische Keramik, die schlagzäh statt spröde ist, erschließt dieser Werkstoffgruppe ganz neue Eigenschaften – zum Beispiel in der Schweißtechnik, im Textilmaschinenbau, in der Mess- und Prüftechnik und in der Montage- und Handhabungstechnik. Neben rein keramischen Bauteilen stehen dem Konstrukteur auch Verbundkonstruktionen zur Verfügung.

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2

Jeltsch-Fricker, R., and S. Meckbach. "Parabolische Mohrsche Bruchbedingung in Invariantendarstellung für spröde isotrope Werkstoffe." ZAMM 79, no. 7 (July 1999): 465–71. http://dx.doi.org/10.1002/(sici)1521-4001(199907)79:7<465::aid-zamm465>3.0.co;2-3.

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3

Heuer, Claudia. "Haifischbecken Hamburg." kma - Klinik Management aktuell 11, no. 04 (April 2006): 36–43. http://dx.doi.org/10.1055/s-0036-1573701.

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Tor zur Welt, Werbung, Medien auf der einen Seite. Hanseatische Arroganz und Spröde auf der anderen. Das Image der Hafenstadt wird sehr kontrovers diskutiert. Die meisten glauben, München sei größer und andere Städte freundlicher. Doch Hamburg ist eine der wenigen wachsenden Städte Deutschlands und dabei, sich zu einer Medizin-Metropole zu entwickeln.

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4

Buehler, Markus J., and Huajian Gao. "Biegen und Brechen im Supercomputer: Duktile Verformungen und spröde Brüche von Kristallen." Physik in unserer Zeit 35, no. 1 (January 2004): 30–37. http://dx.doi.org/10.1002/piuz.200401026.

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5

Itin and Düggelin. "Hair shaft disorders." Therapeutische Umschau 59, no. 5 (May 1, 2002): 228–32. http://dx.doi.org/10.1024/0040-5930.59.5.228.

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Haarschaftanomalien sind klinisch gekennzeichnet durch vermehrte Brüchigkeit und schlechte Kämmbarkeit der Haare. Die Haare sind trocken und spröde mit fehlendem Glanz. Haarschafterkrankungen können lokalisiert oder diffus auftreten und sind entweder anlagebedingt oder erworben. Für die Praxis ist neben Anamnese und Klinik die lichtmikroskopische Betrachtung der Haarschäfte die diagnostisch wichtigste Untersuchungsmethode. Die Behandlung von Haarschafterkrankungen sollte möglichst die Ursache beeinflussen. Praktisch bedeutsam ist eine Vermeidung wiederholter Traumatisierung der Haare. Warmlufttrocknung, Frottieren der Haare, Dauerwellen und aggressive Färbeprozeduren sind bei bestehenden Haarschafterkrankungen ungeeignet. Kosmetisch sind kurze Frisuren günstiger als das Tragen von langen, schütteren Haaren.

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6

Sommer, Nicole Gabriele, and Annelie-Martina Weinberg. "Die Rolle von Magnesium bei Knochenbrüchen in übergewichtigen Kindern und Jugendlichen." Journal für Mineralstoffwechsel & Muskuloskelettale Erkrankungen 28, no. 2 (May 31, 2021): 39–46. http://dx.doi.org/10.1007/s41970-021-00151-z.

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ZusammenfassungDie Inzidenz von Adipositas nimmt dramatisch zu, vor allem bei Kindern und Jugendlichen. Adipositas ist der erste Schritt zum metabolischen Syndrom, welches mit Hypomagnesiämie in Verbindung gebracht wird. Dieses Magnesium (Mg2+)-Defizit und prominente Akteure des metabolischen Syndroms einschließlich Insulinresistenz, Hyperglykämie und Entzündung wurden vor kurzem mit erhöhtem Knochenbruchrisiko bei Erwachsenen assoziiert. Speziell beim Wachstum spielt die richtige Ernährung eine wesentliche Rolle. Mg2+ ist dabei ein essenzieller Schlüsselfaktor, speziell hinsichtlich der skelettalen Reifung von Kindern und Jugendlichen. Hypomagnesiämie führt unweigerlich zu einer reduzierten Knochenmasse, der Knochen wird spröde und das Frakturrisiko steigt. Das höhere Frakturrisiko bei adipösen Kindern und Jugendlichen ist jedoch nach wie vor umstritten: einerseits liegen meist zu niedrige Patientenzahlen in pädiatrischen, klinischen Studien vor, andererseits ist unklar, ob weniger Körperstabilisierung und Koordination infolge geringerer körperlicher Aktivität bei adipösen Kindern und Jugendlichen eine Hauptrolle für die erhöhte Häufigkeit von Knochenbrüchen spielt. Ob die Hypomagnesiämie die Knochenstruktur beeinflusst und eine Schlüsselrolle in der Osteoimmunologie bei Kindern und Jugendlichen darstellt, ist somit noch unzureichend geklärt. Man weiß, dass sich Hypomagnesiämie auch auf die systemische Immunität in einem späteren Lebensabschnitt bei Erwachsenen auswirkt. Veränderungen bei Kindern und Jugendlichen müssen bewertet werden und sollten im Fokus weiterer Untersuchungen stehen.

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7

Spiegl, M., R. Walkner, H. Axmann, E. Pilch, A. Schön, and J. Feix. "Betonschrauben als Durchstanzertüchtigung für statisch und zyklisch belastete Platten/Concrete screws as punching shear strengthening for static and cyclic loaded plates." Bauingenieur 93, no. 07-08 (2018): 274–85. http://dx.doi.org/10.37544/0005-6650-2018-07-08-40.

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Der Durchstanzwiderstand im Bereich des Stützenanschlusses ist heute bei bestehenden Plattenbrücken und Flachdecken im Vergleich zu den rechnerisch anzusetzenden Einwirkungen oft zu gering. Dies ist sowohl durch geänderte Nutzungsbedingungen wie zum Beispiel höhere Lasten als auch durch restriktivere Bemessungsansätze begründet. Herkömmliche Methoden der nachträglichen Durchstanzverstärkung gehen mit hohem Aufwand und hohen Kosten einher, da sie in der Regel bedingen, dass das Tragwerk von der Unter- und Oberseite aus zugänglich sein muss. Das führt zu massiven Nutzungseinschränkungen während der Arbeiten und erfordert zum Beispiel bei Brücken kostenintensive Detaillösungen zur Wiederherstellung der Tragwerksabdichtung. Am Arbeitsbereich Massivbau und Brückenbau der Universität Innsbruck wurde ein technisch innovatives, ressourcenschonendes und wirtschaftliches Verfahren zur nachträglichen Erhöhung des Durchstanzwiderstandes entwickelt, bei dem aus der Verankerungstechnik bekannte Betonschrauben als Verstärkungselemente eingesetzt werden. In diesem Beitrag werden die Ergebnisse von zwei durchgeführten Versuchsserien, bestehend aus elf Versuchsplatten, vorgestellt und miteinander verglichen. Um den möglichen Einsatz des Systems bei Brücken zu verifizieren und die Ermüdungsresistenz des Systems zu untersuchen wurden auch Durchstanzversuche unter zyklischer Belastung durchgeführt. Es zeigt sich, dass mit dem Verstärkungssystem Betonschraube eine signifikante Erhöhung des Durchstanzwiderstandes erzielt wird, das Versagen weniger spröde eintritt und eine zyklische Vorbelastung auf Gebrauchslastniveau keinen negativen Einfluss auf die Verstärkungswirkung des Systems hat.

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8

Mardakheh, Faraz K., Mona Yekezare, Laura M. Machesky, and John K. Heath. "Spred2 interaction with the late endosomal protein NBR1 down-regulates fibroblast growth factor receptor signaling." Journal of Cell Biology 187, no. 2 (October 12, 2009): 265–77. http://dx.doi.org/10.1083/jcb.200905118.

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The potential for modulation of growth factor signaling by endocytic trafficking of receptors is well recognized, but the underlying mechanisms are poorly understood. We examined the regulation of fibroblast growth factor (FGF) signaling by Sprouty related with EVH1 (Ena/VASP homology 1) domain (Spred), a family of signaling inhibitors with proposed tumor-suppressive functions. The inhibitory activity of Spreds has been linked to their N-terminal EVH1 domain, but the molecular mechanism is unknown. In this study, we identify a novel late endosomal protein that directly binds to the EVH1 domain of Spred2. Neighbor of BRCA1 (NBR1) is a highly conserved multidomain protein that interacts and colocalizes with Spred2 in vivo. Attenuation of FGF signaling by Spred2 is dependent on the interaction with NBR1 and is achieved by redirecting the trafficking of activated receptors to the lysosomal degradation pathway. Our findings suggest a critical function for NBR1 in the regulation of receptor trafficking and provide a mechanism for down-regulation of signaling by Spred2 via NBR1.

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9

Hartbrich, Iestyn. "Spröder Charme." VDI nachrichten 75, no. 04 (2021): 22. http://dx.doi.org/10.51202/0042-1758-2021-04-22.

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10

Wazin, Fatima, and Frank J. Lovicu. "The negative regulatory Spred1 and Spred2 proteins are required for lens and eye morphogenesis." Experimental Eye Research 191 (February 2020): 107917. http://dx.doi.org/10.1016/j.exer.2020.107917.

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11

Chen, Yi, Abhidnya A. Deshpande, and Ramazan S. Aygüun. "Sprite generation using sprite fusion." ACM Transactions on Multimedia Computing, Communications, and Applications 8, no. 2 (May 2012): 1–24. http://dx.doi.org/10.1145/2168996.2169002.

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12

Yan, Qiben, Jianzhi Lou, Mehmet C. Vuran, and Suat Irmak. "Scalable Privacy-preserving Geo-distance Evaluation for Precision Agriculture IoT Systems." ACM Transactions on Sensor Networks 17, no. 4 (July 22, 2021): 1–30. http://dx.doi.org/10.1145/3463575.

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Precision agriculture has become a promising paradigm to transform modern agriculture. The recent revolution in big data and Internet-of-Things (IoT) provides unprecedented benefits including optimizing yield, minimizing environmental impact, and reducing cost. However, the mass collection of farm data in IoT applications raises serious concerns about potential privacy leakage that may harm the farmers’ welfare. In this work, we propose a novel scalable and private geo-distance evaluation system, called SPRIDE, to allow application servers to provide geographic-based services by computing the distances among sensors and farms privately. The servers determine the distances without learning any additional information about their locations. The key idea of SPRIDE is to perform efficient distance measurement and distance comparison on encrypted locations over a sphere by leveraging a homomorphic cryptosystem. To serve a large user base, we further propose SPRIDE+ with novel and practical performance enhancements based on pre-computation of cryptographic elements. Through extensive experiments using real-world datasets, we show SPRIDE+ achieves private distance evaluation on a large network of farms, attaining 3+ times runtime performance improvement over existing techniques. We further show SPRIDE+ can run on resource-constrained mobile devices, which offers a practical solution for privacy-preserving precision agriculture IoT applications.

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13

Spreeuwenberg, Lotte. "Liefde aan de basis van moraliteit." Algemeen Nederlands Tijdschrift voor Wijsbegeerte 112, no. 4 (October 1, 2020): 421–24. http://dx.doi.org/10.5117/antw2020.4.011.spre.

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14

Lister, J. M. D., E. J. Divall, S. W. Downes, C. B. Edwards, G. J. Hirst, C. J. Hooker, M. H. Key, I. N. Ross, M. J. Shaw, and W. T. Toner. "Sprite." Journal of Modern Optics 41, no. 6 (June 1994): 1203–15. http://dx.doi.org/10.1080/09500349414551141.

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15

Woldt, D., G. Schubert, and H. G. Jäckel. "Zerkleinerung nicht-spröder Stoffe in Rotorscheren." Chemie Ingenieur Technik 75, no. 12 (December 11, 2003): 1860–63. http://dx.doi.org/10.1002/cite.200303258.

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16

Vedernikov, E. A. "STAGE CUT EFFECT IN SPRUCE SPRUCE FOREST." VESTNIK OF THE BASHKIR STATE AGRARIAN UNIVERSITY 44, no. 4 (December 1, 2017): 97–101. http://dx.doi.org/10.31563/1684-7628-2017-44-4-97-101.

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17

Murtha, P. A. "Photo Interpretation of Spruce Beetle-Attacked Spruce." Canadian Journal of Remote Sensing 11, no. 1 (July 1985): 93–102. http://dx.doi.org/10.1080/07038992.1985.10855081.

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18

Berthiaume, Richard, Christian Hébert, Alain Dupont, Martin Charest, and Éric Bauce. "The spruce budworm, a potential threat for Norway spruce in eastern Canada?" Forestry Chronicle 96, no. 01 (May 2020): 71–76. http://dx.doi.org/10.5558/tfc2020-009.

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Norway spruce, an exotic tree species in North America, was largely used in reforestation programs in the province of Québec between 1972 and 1990. Several of these plantations are now reaching their commercial maturity and the resurgence of spruce budworm outbreak is a reminder that the potential threat of this damaging defoliator for Norway spruce still remains unknown. We used two life-history traits, pupal weight and overwintered larval (L2) weight, to compare spruce budworm biological performance on Norway spruce, white spruce and black spruce. Pupae collected on Norway spruce and overwintered larvae produced by parents that fed on Norway spruce were heavier than those coming from black spruce. Spruce budworm performance was similar on Norway and white spruce, showing similar suitability and suggesting that it can represent a potential threat for Norway spruce plantations established after the last spruce budworm outbreak in eastern North America.

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19

Evans, Nicola. "Spruce app." Nursing Standard 28, no. 49 (August 6, 2014): 33. http://dx.doi.org/10.7748/ns.28.49.33.s40.

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20

Kachuba, John B., and David Long. "Blue Spruce." Antioch Review 53, no. 3 (1995): 372. http://dx.doi.org/10.2307/4613182.

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21

Waddle, Paul Raymond. "Blue Spruce." Theology Today 52, no. 3 (October 1995): 396. http://dx.doi.org/10.1177/004057369505200311.

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22

Parent, Geneviève J., Claudia Méndez‐Espinoza, Isabelle Giguère, Melissa H. Mageroy, Martin Charest, Éric Bauce, Joerg Bohlmann, and John J. MacKay. "Hydroxyacetophenone defenses in white spruce against spruce budworm." Evolutionary Applications 13, no. 1 (December 20, 2019): 62–75. http://dx.doi.org/10.1111/eva.12885.

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23

Perron, M., and J. Bousquet. "Natural hybridization between black spruce and red spruce." Molecular Ecology 6, no. 8 (August 1997): 725–34. http://dx.doi.org/10.1046/j.1365-294x.1997.00243.x.

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24

Reiner-Drehwald, M. Elena. "Las Lejeuneaceae (Hepaticae) de Misiones, Argentina VI. Lejeunea y Taxilejeunea." Bryophyte Diversity and Evolution 19, no. 1 (December 31, 2000): 81–131. http://dx.doi.org/10.11646/bde.19.1.14.

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Fifteen species of Lejeunea and three species of Taxilejeunea (Lejeuneaceae, subfam. Lejeuneoideae) occurring in Misiones, Argentina are described and illustrated: Lejeunea cancellata Nees & Mont., L. filipes Spruce, L. flava (Sw.) Nees, L. geophila Spruce, L. grossitexta (Steph.) E.Reiner & Goda, L. laetevirens Nees & Mont., L. lepida Lindenb. & Gottsche, L. monimiae (Steph.) Steph., L. phyllobola Nees & Mont., L. ptosimophylla C.Massal., L. puiggariana Steph., L. quinqueumbonata Spruce, L. setiloba Spruce, L. tapajosensis Spruce, L. trinitensis Lindenb., Taxilejeunea obtusangula (Spruce) A.Evans, T. pterigonia (Lehm. & Lindenb.) Schiffn. and T. terricola (Spruce) Steph. Five new synonyms (Lejeunea flava (Sw.) Nees [syn. nov.: L. symphoreta Spruce], L. lepida Lindenb. & Gottsche [syn. nov.: L. cladobola Spruce] and L. phyllobola Nees & Mont. [syn. nov.: L. cephalandra Spruce, L. polycephala Spruce and L. brittoniae (A.Evans) Grolle]) and four lectotypifications (L. lepida Lindenb. & Gottsche, L. monimiae (Steph.) Steph., L. phyllobola Nees & Mont. and L. quinqueumbonata Spruce) are proposed. Keys for identification of the species are also provided.

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25

SINGH, S. K. "New combinations in Lejeunea with a new name to Otigoniolejeunea indica." Phytotaxa 96, no. 1 (April 26, 2013): 63. http://dx.doi.org/10.11646/phytotaxa.96.1.3.

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The subgenus Otigoniolejeunea Spruce (1884: 77) of Lejeunea Lib. (1820: 372) was initially described with five species, viz. L. acanthotis Spruce (1884: 227), L. cyrtotis Spruce (1884: 227), L. quinqueumbonata Spruce (1884: 227), L. schizotis Spruce (1884: 227) and L. xiphotis Spruce (1884: 227), all from South America. A few years later, the subgenus was upgraded to genus level by Schiffner (1895) who made the combinations Otigoniolejeunea xiphotis (Spruce) Schiffn. (1895: 125) and O. schizotis (Spruce) Schiffn. (1895: 125). The former species was designated as the lectotype of Otigoniolejeunea by Vanden Berghen (1948).

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26

Holsten, Edward H., and Richard A. Werner. "Comparison of white, Sitka, and Lutz spruce as hosts of the spruce beetle in Alaska." Canadian Journal of Forest Research 20, no. 3 (March 1, 1990): 292–97. http://dx.doi.org/10.1139/x90-043.

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When white spruce is infested with spruce beetle broods, Dendroctonusrufipennis (Kirby), more beetles are produced than when Lutz and Sitka spruce are infested. In spite of host suitability differences, outbreaks of the spruce beetle have been more frequent and severe in stands of Lutz spruce than in white or Sitka spruce. Host suitability may be as important as host susceptibility and weather conditions in the development of spruce beetle outbreaks in south central Alaska. Cool summer temperatures and high precipitation limit the rate of development and growth of beetles in maritime Sitka spruce stands of southeast Alaska, but in white spruce stands of interior Alaska, cold winter temperatures usually help to maintain endemic levels. When these environmental factors are ameliorated, however, spruce beetle populations increase rapidly to epidemic levels.

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27

Keller, H. P. "Ermittlung bruchmechanischer Kennwerte im duktil-spröden Übergang." Materials Testing 32, no. 7-8 (July 1, 1990): 232–37. http://dx.doi.org/10.1515/mt-1990-327-818.

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28

Spur, G., and H. Engel. "Kennwerte des Werkzeugeingriffs beim Läppen spröder Werkstoffe." Zeitschrift für wirtschaftlichen Fabrikbetrieb 92, no. 6 (June 1, 1997): 273–77. http://dx.doi.org/10.1515/zwf-1997-920607.

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29

Rajora, Om P., and Bruce P. Dancik. "Population genetic variation, structure, and evolution in Engelmann spruce, white spruce, and their natural hybrid complex in Alberta." Canadian Journal of Botany 78, no. 6 (June 1, 2000): 768–80. http://dx.doi.org/10.1139/b00-054.

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Genetic variation, structure, and evolution of 12 populations of putative Engelmann spruce (Picea engelmanii Parry), white spruce (Picea glauca (Moench) Voss), and Engelmann - white spruce natural hybrids from the sympatric areas and two populations of white spruce from the allopatric areas in Alberta were examined using 23 allozyme loci coding for 13 enzymes in needles. Although most of the alleles were widespread, unique alleles were found in 9 of the 14 populations. No species-specific allele was observed. However, allele frequency differences were observed between the putative Engelmann and white spruce populations at a number of loci. Frequencies of 13 alleles showed significant correlation with altitude, those of 11 alleles showed correlation with latitude, and those of 3 alleles showed correlation with longitude. On average, 66.2% (99% criterion) of the loci were polymorphic, the number of alleles per locus was 1.88, the number of alleles per polymorphic locus was 2.88, and the observed and expected heterozygosities were 0.063 and 0.184, respectively. Genetic variability of allopatric white spruce, putative Engelmann, sympatric white spruce, and hybrid populations was quite comparable. The mean FST estimate was 0.123 for the total populations. Canonical discriminant functions separated four putative Engelmann spruce populations from the fifth putative Engelmann spruce population and from the allopatric and sympatric white spruce and sympatric putative hybrid populations. A cluster analysis from genetic distances generally separated allopatric and sympatric white spruce populations from the putative Engelmann spruce and hybrid populations. A Wagner tree of the 14 populations produced two main branches; one branch consisting of two allopatric and two sympatric white spruce and one putative hybrid populations, and another branch consisting of the remaining nine spruce populations representing putative Engelmann spruce, putative hybrids, and sympatric white spruce. Putative hybrids showed lower distances to white spruce from the canonical discriminant analysis, whereas they showed lower distances to putative Engelmann spruce from the genetic distance analysis. High allozyme genetic identities between putative Engelmann and white spruce and allelic differentiation related to altitude in Alberta suggest that Engelmann spruce could at best be considered as a subspecies of Picea glauca, with white spruce named as Picea glauca ssp. glauca and Engelmann spruce named as Picea glauca ssp. engelmannii.Key words: Picea glauca, Picea engelmannii, biosystematics, natural hybridization, species differentiation, genetic divergence.

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30

Bobola, Michael S., Denis Guenette, Robert T. Eckert, Anita S. Klein, Karen Stapelfeldt, and Dirk E. Smith. "Using nuclear and organelle DNA markers to discriminate among PicearubensPiceamariana, and their hybrids." Canadian Journal of Forest Research 26, no. 3 (March 1, 1996): 433–43. http://dx.doi.org/10.1139/x26-049.

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The pattern of nuclear ribosomal alleles in controlled-cross black spruce × red spruce hybrids was compared with that of samples from provenance tests of the entire range of red spruce (Picearubens Sarg.) and the eastern complex of black spruce (Piceamariana (Mill.) BSP). In addition, restriction fragment length polymorphisms were identified for the organelle genomes of red spruce and black spruce. Organelle haplotypes were closely associated with species, but were not species specific. Data from controlled-cross hybrids suggest that mitochondria are maternally inherited and chloroplasts are paternally inherited in these spruce species. Organelle markers were combined with restriction fragment length polymorphism data from the nuclear rDNA repeat to derive a simple three-character index capable of identifying red spruce, black spruce, and hybrids of the two species.

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31

Ivanchina, Ludmila A., and Sergei V. Zalesov. "The effect of spruce plantation density on resilience of mixed forests in the Perm Krai." Journal of Forest Science 65, No. 7 (July 31, 2019): 263–71. http://dx.doi.org/10.17221/14/2019-jfs.

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Over the course of the last few decades, many countries across the globe have experienced mass desiccation of spruce plantations. The subject of our research was the spruce forests of the Russian Perm Krai’s mixed forest zone. Spruce is a shade–tolerant tree species and low plantation density may adversely affect the spruce health. The aim of this research is to establish how influential the spruce stand density is on causing desiccation in mixed zones in the Perm Krai. The results of an on-site survey which had recorded spruce desiccation in 2017 were analysed. Within the boundaries of the aforementioned forest areas, 2017 saw the desiccation of spruce trees in 301 forest allotments covering an area of 5,343.7 ha. The value of the weighted average category of spruce forest health in Prikamye varies from 2.7 (severely weakened) to 4.2 (desiccating), and the percentage of the volume of spruce deadwood varies from 17% to 59.5%. When the spruce stand density rises from 0.4 to 0.8, spruce stand resilience to desiccation increases.

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32

Hulme, Michael A., and Allan F. Dawson. "Serbian Spruce is as Vulnerable as Sitka Spruce to Damage by the Sitka Spruce Weevil." Western Journal of Applied Forestry 7, no. 1 (January 1, 1992): 5–6. http://dx.doi.org/10.1093/wjaf/7.1.5.

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Abstract Serbian spruce (Picea omorika) was first damaged naturally by the Sitka spruce weevil (Pissodes strobi) at about 15 years of age in an area on Vancouver Island where this weevil commonly attacks Sitka spruce (Picea sitchensis). By about 20 years of age, all 35 trees in the observation group had been damaged at least once. Serbian spruce cannot therefore be considered a suitable replacement for Sitka spruce in areas where attack by the Sitka spruce weevil is a forest management concern. West. J. Appl. For. 7(1):5-6.

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33

Rangen, Sheila A., Alex W. L. Hawley, and Robert J. Hudson. "Relationship of snowshoe hare feeding preferences to nutrient and tannin content of four conifers." Canadian Journal of Forest Research 24, no. 2 (February 1, 1994): 240–45. http://dx.doi.org/10.1139/x94-035.

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The relative preferences of snowshoe hares for native and exotic tree species and the relationship of these preferences to nutritional constituents and phenols have important forestry management implications. Thus, feeding preferences of confined snowshoe hares (Lepusamericanus Erxleben) for Siberian larch (Larixsibericus (Endl.) Sabine ex Trautv.), Norway spruce (Piceaabies (L.) Karst.), white spruce (Piceaglauca (Moench) Voss), and black spruce (Piceamariana (Mill.) B.S.R) were examined under two experimental ad libitum feeding conditions. At the end of experiment 1, two-year-old Siberian larch and Norway spruce were equally selected by hares. Twigs and stems of Siberian larch, however, were browsed almost exclusively during the first few days of the experiment, while white spruce was browsed very little at all. Siberian larch was richer in crude protein and lower in fiber than white spruce and Norway spruce, whereas Norway spruce was lower in condensed tannins and total phenols than the other two species. In experiment 2, twigs and stems of 4-year-old black spruce were preferred to those of white spruce. Black spruce contained significantly higher concentrations of crude protein, calcium, and phosphorus and lower concentrations of cellulose and total phenols than white spruce. Overall, white spruce was most resistant to hare damage, though the lack of preference was not reflected in either low nutrient or high tannin values. In fact, concentrations of condensed tannins and total phenols had no antifeedant effects.

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Savidge, Rodney Arthur. "Porsild spruce in Canada – an update." Forestry Chronicle 90, no. 01 (January 2014): 105–7. http://dx.doi.org/10.5558/tfc2014-016.

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Several new developments are noted since publication of “Porsild spruce in Canada” in The Forestry Chronicle in January 2013. Firstly, Porsild spruce has been found in northeastern Quebec. Secondly, although researchers were unaware of the fact until now, the Porsild spruce phenotype has been found to be a common component in the New Brunswick tree improvement program’s second-generation seed orchard in support of reforestation. Thirdly, a wild tree discovered in New Brunswick displays morphological features of Engelmann spruce and, based on observed similarities between Yukon Beringia Porsild spruce phenotypes and the accepted Engelmann spruce phenotype, it is possible that the New Brunswick Engelmann spruce tree was derived from the local Porsild spruce population.

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Berthiaume, Richard, Christian Hébert, Martin Charest, Alain Dupont, and Éric Bauce. "Host Tree Species Affects Spruce Budworm Winter Survival." Environmental Entomology 49, no. 2 (March 11, 2020): 496–501. http://dx.doi.org/10.1093/ee/nvaa020.

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Abstract With current trends in global warming, it has been suggested that spruce budworm outbreaks may spread to northern parts of the boreal forest. However, the major constraints for a northward expansion are the availability of suitable host trees and the insect winter survival capacity. This study aimed to determine the effect of larval feeding on balsam fir, white spruce and black spruce on various spruce budworm life history traits of both the parental and the progeny generations. Results indicated that the weight of the overwintering larval progeny and their winter survival were influenced by host tree species on which larvae of the parental generation fed. White spruce was the most suitable host for the spruce budworm, producing the heaviest pupae and the heaviest overwintering larvae while black spruce was the least suitable, producing the smallest pupae and the smallest overwintering progeny. Overwintering larvae produced by parents that fed on black spruce also suffered higher winter mortality than individuals coming from parents that fed on balsam fir or white spruce. With current trends in global warming, spruce budworm is expected to expand its range to northern boreal forests where black spruce is the dominant tree species. Such northern range expansion might not result in outbreaks if low offspring winter survival on black spruce persist.

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Spies III, Charles J., and J. B. Dimond. "SEPARATING EARLY LARVAE OF SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE) AND SPRUCE CONEWORM, DIORYCTRIA RENICULLELOIDES (LEPIDOPTERA: PYRALIDAE) IN SURVEYS OF OVERWINTERING LARVAE." Canadian Entomologist 117, no. 2 (February 1985): 261–63. http://dx.doi.org/10.4039/ent117261-2.

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The spruce coneworm, Dioryctria reniculleloides (Mut. and Mun.), is often associated with the spruce budworm on spruce host trees and sometimes approaches or equals the spruce budworm, Choristoneura fumiferana (Clem.), in numbers (Spies and Dimond 1985). The coneworn is probably~responsiblefo r some of the damage on spruce attributed to the budworm, and with much balsam fir in eastern North America now dead from defoliation or harvested, there is increasing interest in spruce as the major resource to protect.

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Page, Wesley G., Michael J. Jenkins, and Justin B. Runyon. "Spruce Beetle-Induced Changes to Engelmann Spruce Foliage Flammability." Forest Science 60, no. 4 (August 19, 2014): 691–702. http://dx.doi.org/10.5849/forsci.13-050.

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Schumacker, R., C. Cortini Pedrotti, A. Von HÜBschmann, R. Düll, and G. Schwab. "Scopelophila ligulata (Spruce) Spruce (Pottiaceae, Bryophytina), nouveau pour l'Italie." Webbia 43, no. 1 (January 1989): 139–44. http://dx.doi.org/10.1080/00837792.1989.10670450.

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Li, Dan, Rebecca A. Jackson, Permeen Yusoff, and Graeme R. Guy. "Direct Association of Sprouty-related Protein with an EVH1 Domain (SPRED) 1 or SPRED2 with DYRK1A Modifies Substrate/Kinase Interactions." Journal of Biological Chemistry 285, no. 46 (August 24, 2010): 35374–85. http://dx.doi.org/10.1074/jbc.m110.148445.

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40

Matsuoka, Steven M., Colleen M. Handel, and Daniel R. Ruthrauff. "Densities of breeding birds and changes in vegetation in an Alaskan boreal forest following a massive disturbance by spruce beetles." Canadian Journal of Zoology 79, no. 9 (September 1, 2001): 1678–90. http://dx.doi.org/10.1139/z01-130.

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We examined bird and plant communities among forest stands with different levels of spruce mortality following a large outbreak of spruce beetles (Dendroctonus rufipennis (Kirby)) in the Copper River Basin, Alaska. Spruce beetles avoided stands with black spruce (Picea mariana) and selectively killed larger diameter white spruce (Picea glauca), thereby altering forest structure and increasing the dominance of black spruce in the region. Alders (Alnus sp.) and crowberry (Empetrum nigrum) were more abundant in areas with heavy spruce mortality, possibly a response to the death of overstory spruce. Grasses and herbaceous plants did not proliferate as has been recorded following outbreaks in more coastal Alaskan forests. Two species closely tied to coniferous habitats, the tree-nesting Ruby-crowned Kinglet (Regulus calendula) and the red squirrel (Tamiasciurus hudsonicus), a major nest predator, were less abundant in forest stands with high spruce mortality than in low-mortality stands. Understory-nesting birds as a group were more abundant in forest stands with high levels of spruce mortality, although the response of individual bird species to tree mortality was variable. Birds breeding in stands with high spruce mortality likely benefited reproductively from lower squirrel densities and a greater abundance of shrubs to conceal nests from predators.

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Иванчина, Людмила, Lyudmila Ivanchina, Сергей Залесов, Sergey Zalesov, Алексей Кожевников, and Aleksey Kozhevnikov. "DIVERSITY OF SPRUCE SELECTIVE FORMS ACCORDING TO THEIR BARK IN PRIKAMYE." Vestnik of Kazan State Agrarian University 14, no. 3 (October 30, 2019): 37–42. http://dx.doi.org/10.12737/article_5db8561af22296.43255366.

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Lately in many countries of the world there has been a massive drying up of spruce stands. Bark form testifies to trees stability to environmental unfavorable factors. Investigations were underway in the central part of Russia, in the zone of coniferous-broadleaved (mixed) forests of Permsky kray. Above scientists established that in the Permsky kray spruce trees with smooth, scaled and longitudinally fissured fracture bark types can be found. The purpose is to determine spruce selective forms the most stable for drying off according to their bark structure. Based on the materials of 9 sample plots, it was established that the sanitary condition of the spruce trees in all the investigated spruce stands was unsatisfactory. According to investigation data in all the SP stands there are dried off trees whose number a varied from 28.4 to 69.6 %. The results of investigations have shown that in stands of all sample plots specimen of spruce with scaled bark form are prevailed. The number of spruce trees with scaled bark varies from 83.1 to 98.9%. Rarely are spruce trees with longitudinally fissured and smooth bark types. We succeeded in singling out a new spruce form according bark structure – smooth warty form too. Share of spruce trees with this bark type does not exceed 4.2 % on stocking. Spruce trees of all the bark forms are subjected significantly to drying off, except the trees with smooth warty form. The conservation of spruce trees with a smooth warty bark form is 100 % on all SP within which specimens of spruce of this bark form were found.

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Ledig, F. Thomas, Paul D. Hodgskiss, and David R. Johnson. "The structure of genetic diversity in Engelmann spruce and a comparison with blue spruce." Canadian Journal of Botany 84, no. 12 (December 2006): 1806–28. http://dx.doi.org/10.1139/b06-106.

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Genetic diversity and genetic structure in Engelmann spruce (Picea engelmannii Parry ex Engelm.) were interpreted with respect to the effects of glacial and interglacial displacement and compared with patterns in blue spruce (Picea pungens Engelm.), which occupies a range well south of the last glacial front. On average, Engelmann spruce populations were polymorphic at 80% of 24 isozyme loci, with 2.4 alleles per locus and expected heterozygosity of 0.255. The respective means for four populations of blue spruce were 42.7%, 1.6 alleles, and 0.138. Of total diversity, 14.7% was among populations in Engelmann spruce and 8.6% in blue spruce. In Engelmann spruce, numbers of alleles increased from south to north. Recent bottlenecks were indicated in the three southernmost populations of Engelmann spruce and in the northernmost population of blue spruce. Cluster analysis divided Engelmann spruce into a northern group and a Southwestern group; however, populations from Utah were distributed among both clusters. Genetic distance was correlated with geographic distance between northern populations but not between Southwestern populations, where drift predominated over gene flow. In two Engelmann spruce populations from Utah, multilocus outcrossing rates were 0.951 (±0.016) and 0.940 (±0.071). At Flys Peak, Arizona, the southernmost location of Engelmann spruce, outcrossing was also high, 0.899 (±0.017). Thus, inbreeding coefficients observed for parental (–0.104 to 0.047) and filial (0.011 to 0.026) generations were low. Although Engelmann spruce seemed genetically robust, the evidence of bottlenecks in the southern extreme of its range suggested future problems in an era of global warming.

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Modlinger, Roman, and Jan Liška. "Review of Lepidoptera with trophic relationships to Picea abies (L.) in the conditions of Czechia." Forestry Journal 62, no. 4 (December 1, 2016): 178–94. http://dx.doi.org/10.1515/forj-2016-0015.

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Abstract Trophic relationships of Lepidoptera (Insecta) occurring in the territory of Czechia to the Norway spruce (Picea abies L.) was evaluated on the basis of the excerption and critical evaluation of literature. Each species was classified into the following categories – spruce as the host plant, regular development on spruce, narrow trophic relationship, indirect relationship and episodical occurrence. The particular taxa were also characterized according to their distribution and the form of larval life was specified. The development on spruce was documented in 96 species of Lepidoptera, which represented less than 3% of taxa belonging to this group and being reported from Czechia. Of that, spruce was a common host plant for 67 species, 23 species were polyphagous and might develop on spruce, and 6 species belonged to soil species damaging spruce roots, mainly in forest nurseries. Among the species of Lepidoptera, which regularly develop on spruce in the Czech conditions, 55 species were classified. As narrow specialists with special trophic relationship to spruce, 33 taxa could be considered. There were 15 spruce species with forestry importance, which were able to outbreak their populations regularly or irregularly. Among spruce species it was possible to classify 16 taxa as rare. The provided information on Lepidoptera with trophic relationship to spruce is applicable also for other Central European areas. Besides the species with importance for forest pest management, also rare taxa, which can become endangered by climate change or by forest management, were indicated.

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44

Fogal, W. H., S. M. Lopushanski, H. O. Schooley, and D. A. Winston. "Reproductive development and insect damage on white and black spruce seed trees treated with ammonium nitrate and carbofuran." Canadian Journal of Forest Research 23, no. 9 (September 1, 1993): 1786–92. http://dx.doi.org/10.1139/x93-226.

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Granular ammonium nitrate and carbofuran were applied to soil beneath white spruce (Piceaglauca (Moench) Voss) and black spruce (Piceamariana (Mill.) B.S.P.) seed trees to stimulate reproductive development and protect them from defoliating and cone-feeding insects. Rates of carbofuran application were 0, 10.8, or 21.6 g/cm DBH for white spruce, and 0, 5, or 10 g/cm DBH for black spruce. Both species received 0,224, or 448 kg N/ha of ammonium nitrate. Trees were assessed for defoliation by the eastern spruce budworm (Choristoneurafumiferana Clem.), cone insect damage, seed-cone bud production, cone production, seed yields, and needle senescence for 3 years in white spruce, and 2 years in black spruce. On white spruce, carbofuran reduced defoliation and number of spruce budworm at both application rates in the year of treatment and at the high rate in the second year; no protection was observed in the third year. Seed-cone bud production was stimulated by carbofuran for 3 years following treatment. Needle senescence was increased by carbofuran. Ammonium nitrate decreased needle senescence but had no effects on other assessment variables. On black spruce, carbofuran did not reduce spruce budworm numbers or protect cones in the year of application but, in the year after treatment, both foliage and cones were protected. Defoliation was reduced by the low rate of applied ammonium nitrate. Treatments did not influence the number of seed-cone buds or cones or amount of needle senescence in black spruce.

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45

Simard, Martin, and Serge Payette. "Reduction of black spruce seed bank by spruce budworm infestation compromises postfire stand regeneration." Canadian Journal of Forest Research 35, no. 7 (July 1, 2005): 1686–96. http://dx.doi.org/10.1139/x05-083.

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In the southern boreal forest of eastern Canada, black spruce (Picea mariana (Mill.) BSP) is subjected to both defoliating insect and fire disturbances. As black spruce depends on its aerial seed bank for postfire regeneration, reduction of cone crop during a spruce budworm (Choristoneura fumiferana (Clem.)) outbreak opens a vulnerability window during which stand regeneration could be hindered in the event of a fire. To assess the long-term effect of spruce budworm outbreak on black spruce reproductive potential, cone production and viable seed bank were estimated using cone crop surveys and germination trials in black spruce lichen woodland stands that sustained different levels of defoliation during the 1980s. Black spruce cone crop was significantly related to the defoliation history of the stands (R2 = 0.89), but not to stand age, basal area, or tree density. Black spruce stands damaged by severe defoliation showed a smaller number of cones, a higher incidence of insect-damaged cones, and a viable seed bank 3 to 17 times smaller than a lightly defoliated stand. The vulnerability window for black spruce regeneration following a spruce budworm outbreak may be as long as 20 years in the study area because black spruce seed bank in heavily defoliated stands has not yet replenished. Our work supports conclusions from stand reconstruction studies that suggest closed-crown sprucemoss stands convert to open lichen woodlands as a result of weak postfire regeneration caused by successive insect and fire disturbances.

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46

Skosyreva, I. G., and A. I. Grigoriev. "VARIABILITY OF CONES AND SEEDSCALESIN PICEA SPECIES AND THEIR FORMS IN CONDITIONS OF THE CITY OF OMSK." Bulletin of Nizhnevartovsk State University, no. 2 (June 15, 2019): 37–43. http://dx.doi.org/10.36906/2311-4444/19-2/05.

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The study addressedthe morphometric indicators of cones and seed scales, such as length, width, and weight (before opening and after drying). Similarly, seed scales were measured, the marginal lines were described, and the number of seed scales in the cones was counted. The summary tables showed significant differences in the length and width of cones (Student's criterion). The correlation analysis was used to quantify the association between various indicators and the seed scale size. The samples were collected in the Genze Dendrological Garden, a natural landmark of regional significance. The study was carried out usingMolchanov and Smirnov’s (1967) method in the summer-autumn period. Siberian spruce (both blue and green forms), Serbian spruce, Colorado spruce (green form), and Canadian spruce had medium and large cones, which indicates a high adaptive capacity of these species. The length of cones in blue-grey and golden forms of Colorado spruce was below the average, indicating a low adaptive ability of the introduced species in the West Siberian foreststeppe. The correlation analysis showed a moderate dependence of the weight of seed scales and the weight of cones after drying (K = 0.60). A small dependence was found between the weight of seed scales and the length of cone after drying (K = 0.39). The size of seed scales strongly correlated with the size of cones (K ˃ 0.8). Student's t-test did not reveal significant differences in the width of cones in the studied species and forms of spruce, except for green form of Colorado spruce as compared to Serbian spruce and Canadian spruce, and blue-grey form of Colorado spruce as compared to Canadian spruce , showing notable differences at 1% significance point. By the length of cones, the studied species can be categorized into twoessentially different groups, the first one including all forms of Siberian spruce and Colorado spruce and the second one including Serbian spruce and Canadian spruce .

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47

Pukinskaya, M. Yu. "Tree Change in Nemoral Spruce Forests of the Central Forest Reserve." Povolzhskiy Journal of Ecology, no. 4 (January 13, 2021): 459–76. http://dx.doi.org/10.35885/1684-7318-2020-4-459-476.

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The paper discusses changes in forest-forming species in the nemoral spruce forests of the Central Forest Reserve (Tver Region, the Russian Federation). A comparison is made of the characterization of vegetation in the reserve spruce forests, carried out during the first survey of the reserve by Ya. Ya. Alekseev in 1931 (Alekseev, 1935) with the descriptions of vegetation made by the author from 2011 to 2019. It is shown that the coverage of nemoral herbs in the spruce forests of the reserve has increased over the past 90 years. In addition, three types of broadleaf trees (Tilia cordata Mill., Acer platanoides L. and Ulmus scabra Mill.) have greatly increased their abundance in the stand, most notably the linden. In recent decades, the decay of nemoral spruce forests has been taking place in the Central Forest Reserve. The birch-aspenspruce stand is not replenished with spruce renewal but is replaced by linden-maple forests. The vitality of spruce undergrowth is deteriorating. After the decay of a spruce forest, a change of the tree dominants occurs on 74% of the trial plots and the stand continues with a spruce forest on 26%. The largest part of the reserve's nemoral spruce forests arose after major disturbances 100–150 years ago (on the site of burned-out areas, hurricane windblows and cuttings). Old nemoral spruce forests were formed during the period when severe frosts prevented linden and maple from entering the stand. Currently, the coincidence of climate warming with the aging of the spruce stand and the removal of anthropogenic influence contributed to the release of maple and linden from the undergrowth into the stand and change to a spruce-deciduous forest. Under the prevailing climatic conditions, a return to the spruce forest is possible in the event of a burning out or when the climate becomes cold. The nemoral spruce forest is an ecotone type and, depending on conditions, becomes a spruce or broad-leaved forest.

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48

Wang, G. Geoff, J. Aurea Siemens, Vince Keenan, and Daniel Philippot. "Survival and growth of black and white spruce seedlings in relation to stock type, site preparation and plantation type in southeastern Manitoba." Forestry Chronicle 76, no. 5 (October 1, 2000): 775–82. http://dx.doi.org/10.5558/tfc76775-5.

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Differences in survival and growth of black and white spruce seedlings planted on boreal mixedwood sites were tested for stock types (transplant versus container), site preparation (Donaren disc trenching versus no trenching), and plantation types (open versus sheltered) in southeastern Manitoba after eight or nine growing seasons. Mortality of open plantation (32.3%) and container stock (32.5%) were significantly higher than sheltered plantation (23.7%) and transplant stock (22.8%), respectively. Donaren trenching slightly reduced the mortality of black spruce but significantly increased the mortality of white spruce. Seedlings of container stock (110 cm) were significantly shorter than transplant stock (157 cm). Significant difference in height was found between open and sheltered plantations for black spruce but not for white spruce. Root collar diameter of container stock (15.6 mm) was significantly smaller than transplant stock (23.1 mm). Root collar diameter in sheltered plantations was significantly larger than that in open plantations for black spruce but not for white spruce. Black spruce open plantation had significantly smaller volume (97 cm3) compare to black spruce sheltered (210 cm3) and white spruce open (175 cm3) and sheltered (229 cm3) plantations. White spruce open plantations also had smaller volume than white spruce sheltered plantations. Container stock had smaller volume (89 cm3) than transplant stock (267 cm3). For transplant stock, strip plantations had a significantly higher volume (329 cm3) than open plantations (204 cm3). Based on above results, we recommend that (1) transplant stock should be used, (2) sheltered plantation site preparation should be used on boreal mixedwood sites, and (3) Donaren disc-trenching is not necessary for planting white spruce. Key words: silviculture, boreal mixedwood site, plantation

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Иванчина, Людмила, Lyudmila Ivanchina, Сергей Залесов, Sergey Zalesov, Евгения Залесова, and Evgeniya Zalesova. "The Influence of the Composition of the Forest on Spruce Drying." Forestry Engineering Journal 7, no. 3 (November 1, 2017): 66–74. http://dx.doi.org/10.12737/article_59c22283397940.25025127.

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Plantions of pleurocarpous moss spruce forest type are dominant in the area of coniferous-deciduous (mixed) forests of the European part of the Russian Federation in Perm region. The problem of drying of spruce forests has aggravated dramatically in recent years. However, among scientists there is no consensus on the causes of the drying of spruce forests, which hinders the development of recommendations on improvement of forest management in spruce forests. In this regard spruce plantations in Perm region are not exceptions. On the basis of acts of forest pathology survey, drying of pleurocarpous moss spruce forest with different composition of forest stands is analyzed. The drying area for the period from 2010 to 2016 at Ocherskoe forestry in Perm region (forest area of coniferous-deciduous (mixed) forests of the European part of the Russian Federation) is mapped to a planted area of pleurocarpous moss spruce forest of different species composition. It was found that there was no drying out spots for the analyzed period in plantings of pleurocarpous moss spruce forest with a mixture of softwood species. As well as stands with admixture of fir and birch are characterized by high resistance. Among the identified drying out spots of spruce the most represented are plantations which contain of spruce, fir and pine (28.1 % of the total area of drying out spots), as well as spruce, fir, pine and birch (22.56 % of the total area of drying out spots). Data on the influence of the composition of the forest on mortality of spruce in the conditions of pleurocarpous moss spruce forest can be used in forming thinnings, as well as creation of forest crops.

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50

Grossnickle, Steven C. "Influence of flooding and soil temperature on the water relations and morphological development of cold-stored black spruce and white spruce seedlings." Canadian Journal of Forest Research 17, no. 8 (August 1, 1987): 821–28. http://dx.doi.org/10.1139/x87-130.

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Fall-lifted, cold-stored black spruce (Piceamariana (Mill.) B.S. P.) and white spruce (Piceaglauca (Moench) Voss) seedlings [Formula: see text] were planted in a controlled environmental chamber with an air temperature of 20 °C, soil temperatures of 10 or 20 °C, and flooded or nonflooded soil treatments. Stomatal conductance (gwv) was lower in flooded seedlings compared with nonflooded seedlings for both black spruce and white spruce seedlings. Black spruce seedlings drained after 14 days of flooding showed gwv similar to nonflooded seedlings, while drained white spruce seedlings had gwv patterns greater than nonflooded seedlings. White spruce seedlings had diurnal xylem pressure potential (ψx) patterns slightly more negative in the flooded treatment compared with the nonflooded treatment. Measured predawn ψx was found to be more negative in flooded seedlings compared with nonflooded seedlings in both black spruce and white spruce. In both species, flooded seedlings 1 day out of cold storage had a greater resistance to water flow through the soil–plant–atmosphere continuum (RSPAC) compared with non-flooded seedlings. After 21 days out of cold storage, rspac decreased in nonflooded seedlings of both species, while flooded seedlings of both species had high RSPAC values. For both black spruce and white spruce seedlings, flooded soils inhibited root growth, while low soil temperatures resulted in a reduction in root growth in nonflooded seedlings. Shoot growth of white spruce seedlings was not influenced by 21 days of flooding or low soil temperature, while the combination of 21 days of flooding and low soil temperature in black spruce seedlings resulted in less shoot development compared with nonflooded seedlings.

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