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Background: The purpose of this 6‐week, single‐blinded, randomized clinical trial was to determine if the use of an interproximal brush, with or without a tracking device, is more effective than an oral irrigator in improving interproximal probing depth (PD), clinical attachment level (CAL), plaque index (PI), gingival index (GI), bleeding on probing (BOP), and inflammatory markers. Methods: Seventy‐six patients with Stages III–IV, Grade B periodontitis and a 5–7 mm posterior interproximal PD with BOP were randomized: (1) interproximal brush alone (IB; n = 26), (2) interproximal brush with tracking device (TD; n = 23), (3) oral irrigator (OI; n = 27). Participants used devices once daily for 6 weeks. Clinical measurements (PD, CAL, PI, BOP, GI) and gingival crevicular fluid (GCF) samples were collected at baseline and 6 weeks. Results: All groups showed a significant reduction in PD and CAL (≥1.1 mm, p < 0.0001) and improvement in BOP (≥56%, p < 0.0001) and GI (≥82%, p < 0.001) at the experimental site with no differences among groups. The IB and IB+TD groups showed a significant reduction in PI (≥0.9, p ≤ 0.01). Interleukin (IL)‐1β was reduced in all groups (p = 0.006), but IB+TB more than OI (p ≤ 0.05). IL‐10 was reduced among all groups (p = 0.01), while interferon‐gamma significantly increased (p = 0.01) in all groups. Conclusions: IB and OI improved clinical parameters of PD and CAL and reduced inflammatory markers (BOP, GI, GCF IL‐1β). IB had better interproximal plaque reduction. Tracking did not significantly improve clinical parameters compared with the IB and OI groups, suggesting future modifications are needed. [ABSTRACT FROM AUTHOR]

Fire scars are initiated by cambial necrosis caused by localized lethal heating of the tree stem. Scars develop as part of the linked survival processes of compartmentalization and wound closure. The position of scars within dated tree ring series is the basis for dendrochronological reconstruction of fire history. Macroanatomical features were described for western larch (Larix occidentalis Nutt.), ponderosa pine (Pinusponderosa Douglas ex P. Lawson & C. Lawson), and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) injured by fire in 2003 and harvested in 2011 at the Lolo National Forest near Missoula, Montana, USA. Bark scorch did not necessarily indicate the formation of a scar. Wound-initiated discoloration inward from the scar face was bounded tangentially by reaction zones. In western larch, the transition between earlywood and latewood was much less abrupt in woundwood rings than in rings formed the same year but not associated with a scar. Wood formed the year after injury contained tangential rows of resin ducts in the earlywood. Compartmentalization plays a key role in resisting the spread of infection and the loss of healthy sapwood and heartwood. Wound closure restores some degree of circumferential continuity of the vascular cambium and reinforces stem structure. The terminology presented here should facilitate communication among tree pathologists, wound anatomists, and dendrochronologists. Key words: fire injury, fire history, dendrochronology, wound pathology, reaction zone, barrier zone, bluestain, conifer defense. Les cicatrices de feu resultent de la necrose du cambium causee par une chaleur letale localisee sur le tronc des arbres. Elles font partie des processus de survie inter-relies que sont le compartimentage et la fermeture de la blessure. La position des cicatrices dans les series dendrochronologiques datees constitue les fondements de la reconstitution dendrochronologique de l'historique des feux. Les caracteristiques macroanatomiques ont ete decrites chez le meleze occidental (Larix occidentalis Nutt.), le pin ponderosa (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) et le douglas de Menzies bleu (Pseudotsuga menziesii (Mirb.) Franco) endommages par le feu en 2003 et recoltes en 2011 a la foret nationale de Lolo pres de Missoula dans l'Etat du Montana, aux Etats-Unis. De fa^on generale nous avons observe que la presence d'une roussissure de l'ecorce n'entrainait pas necessairement la formation d'une cicatrice. La coloration du bois causee par la blessure derriere la cicatrice etait limitee tangentiellement par les zones de reaction. Chez le meleze occidental, la transition entre le bois initial et le bois final etait beaucoup moins abrupte dans les cernes annuels associes a la blessure que dans les cernes annuels formes la meme annee mais distants de la blessure. Le bois forme l'annee suivant la blessure contenait des rangees tangentielles de canaux resiniferes dans le bois initial. Le pin ponderosa completait la differenciation duxyleme plus tard que le meleze occidental et que le douglas de Menzies bleu. Le compartimentage joue un role cle dans la resistance a la propagation de l'infection et la perte de bois d'aubier et de bois de creur sains et fonctionnels. La fermeture de la blessure restaure un certain degre de continuite circonferentielle du cambium vasculaire et assure le renforcement structural du tronc endommage. La terminologie coherente presentee dans cet article devrait faciliter la communication entre les phytopathologistes, les anatomistes du bois et les dendrochronologistes. [Traduit par la Redaction] Mots-cles : blessure causee par le feu, historique des feux, dendrochronologie, pathologie des blessures, zone de reaction, zone barriere, bleuissement, mecanismes de defense des coniferes., Introduction The dendrochronological record of fire scars provides the primary evidence of the timing, geographic extent, and other properties of forest fire regimes across scales of space and time (Swetnam [...]

Fungi in the Agaricomycetes (Basidiomycota) are the primary decomposers in temperate forests of dead wood on and in the forest soil. Through the use of isolation techniques selective for saprotrophic Agaricomycetes, a variety of wood decay fungi were isolated from a northern hardwood stand in the Bartlett Experimental Forest, New Hampshire, USA. In particular, Hypholoma lateritium (Schaeff.: Fr.) P. Kumm. was isolated from basidiocarps, decaying Acer rubrum L. logs, the Oe organic soil horizon, and the E and BC mineral soil horizons. Identification was confirmed by sequence analysis of the internal transcribed spacer region of nuclear ribosomal DNA. All isolates had identical sequences in this region to previously published sequences for the species; some were monokaryotic and simple-septate and others were dikaryotic, with clamp connections. Isolates were further characterized by banding patterns (DNA fingerprints) produced with PCR primers based in simple repetitive sequences and the minisatellite M13. Nine dikaryotic isolates from basidiocarps and from soil horizons Oe, E, and BC had identical fingerprint patterns with all primers tested. The confirmed presence of H. lateritium suggests that this fungus could form a mycelial translocation network that bridges mineral and organic soil horizons and decaying logs. Key words: Hypholoma sublateritium, DNA fingerprinting, nutrient recycling, coarse woody debris, DAPI. Les champignons appartenant aux Agaricomycetes (Basidiomycota) venant sur le bois mort et les sols forestiers representent les decomposeurs primaires des forets temperees. A l'aide d'une technique d'isolement selective pour les Agaricomycetes, les auteurs ont obtenu une variete de champignons decomposeurs du bois, dans un peuplement nordique de bois feuillus de la Foret experimentale de Bartlett, dans l' etat du New Hampshire aux Etats-Unis. Ils ont obtenu en particulier l'Hypholoma lateritium (Schaeff. : Fr.) P. Kumm, a partir de basidiocarpes, de billes d Acer rubrum L. en decomposition, ainsi que de l horizon organique Oe et des horizons mineraux E et BC du sol. Ils en ont confirme l identification par l analyse des sequences de la region de l espaceur interne transcrit de l ADN ribosomal nucleique. Tous les isolats montrent pour cette region des sequences identiques aux sequences deja publiees pour cette espece; on y trouve des isolats a monocaryons avec septations simples et d autres a dicaryons avec anses d anastomose. Les auteurs ont poursuivi la caracterisation a partir de patrons de bandes (empreintes ADN) produits avec des amorces et PCR basees sur des sequences repetitives simples et du microsatellite M13. Neuf isolats dicaryotiques provenant de basidiocarpes et des horizons Oe, E, et BC du sol montrent des empreintes identiques, avec toutes les amorces. La presence confirmee du H. lateritius suggere que ce champignon pourrait former un reseau mycelien de translocation, faisant le pont entre les horizons mineraux et organiques du sol, avec le bois en decomposition. Mots-cles : Hypholoma sublateritium, empreinte ADN, recyclage des elements, debris ligneux grossiers, DAPI. [Traduit par la Redaction], Introduction Coarse woody debris (CWD), defined as fallen limbs and tree boles having a diameter greater than 10 cm (Harmon et al. 1986), is a major element of the carbon [...]

The depletion of root-available Ca in northern forest soils exposed to decades of increased acid deposition adversely affects forest health and productivity. Laboratory studies indicated the potential of wood-decay fungi to restore lost Ca. This study presents changes in concentration of Ca, Mg, and K in sapwood of red spruce (Picea rubens Sarg.), red maple (Acer rubrum L.), eastern hemlock (Tsuga canadensis (L.) Carriere), and paper birch (Betula papyrifera Marshall) during the decay process at two experimental forests for 12 years and to compare concentrations of exchangeable Ca, Mg, and Al in decayed wood residues at 10 and 12 years with those in the forest floor. Significant loss of mass indicated by decreasing wood density occurred after 2-8 years in conifers and after only 2 years in hardwoods. A significant gain in wood K was observed at 2 years followed by a significant loss at 8 years. A negligible gain in Ca concentration occurred at 2 years and a substantial gain at 8 years. Observed changes in Mg concentration were variable. No significant difference in exchangeable Ca concentration was observed between decayed wood residue of spruce and maple and the forest floor. However, decayed wood residue had a much lower Al concentration and molar Al/Ca ratio, a condition characteristic of sites with high root-available Ca. Resume: La diminution du Ca disponible pour les racines dans les sols des forets nordiques exposees a plusieurs decennies de depots acides accrus affecte la sante et la productivite de la foret. Des etudes en laboratoire ont montre que les champignons de carie du bois avaient la capacite de restaurer le Ca perdu. Cette etude presente l'evolution de la concentration de Ca, Mg et K dans le bois d'aubier de l'epinette rouge (Picea rubens Sarg.), de l'erable rouge (Acer rubrum L.), de la pruche du Canada (Tsuga canadensis (L.) Carriere) et du bouleau a papier (Betula papyrifera Marshall) durant le processus de decomposition dans deux forets experimentales pendant 12 ans et compare les concentrations de Ca, Mg et Al echangeables dans les debris ligneux apres 10 et 12 ans a celles qu'on retrouve dans la couverture morte. Une perte importante de masse, comme le revele la diminution de la densite du bois, est survenue apres 2 a 8 ans chez les coniferes et apres seulement deux ans chez les feuillus. Un gain important en K dans le bois a ete observe apres 2 ans suivi par une perte importante apres 8 ans. Un gain negligeable dans la concentration de Ca est survenu apres 2 ans suivi d'un gain substantiel apres 8 ans. Les changements observes dans la concentration de Mg etaient variables. Aucune difference significative n'a ete observee dans la concentration de Ca echangeable entre les debris ligneux caries d'epinette, d'erable et la couverture morte. Cependant, les debris ligneux caries avaient une concentration en Al et un rapport molaire Al/Ca beaucoup plus faibles, une situation caracteristique des stations ou la disponibilite de Ca pour les racines est elevee. [Traduit par la Redaction], Introduction Calcium is the fifth most abundant element in the earth's crust. Other than N, Ca is considered the most important essential mineral for managing plant diseases (Rahman and Punja [...]

Abstract: The decay of coarse woody debris is a key component in the formation of forest soil and in the biogeochemical cycles of Ca and Mg. We tracked changes in [...]

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