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Plant food wastes generated through the food chain have attracted increasing attention over the last few years not only due to critical environmental and economic issues but also as an available source of valuable components such as dietary fibers. However, the exploitation of plant waste remains limited due to the lack of appropriate processing technologies to recover and tailor fiber functionalities. Among the different technologies developed for waste valorization, mechanical techniques were suggested to be a promising and sustainable strategy to extract fibers with improved functionalities. In this context, the present review describes different mechanical technologies (conventional and innovative) with potential applications to produce micro/nanofibers from various plant residues, highlighting the operating principle as well as the main advantages and pitfalls. The impact on the structural, technological, and functional properties of fibrous materials is comprehensively discussed. The extent of fiber modification not only highly depended on the technology and operation conditions used but also on fiber composition and the application of posttreatments such as dehydration. Other variables, including economic and environmental issues such as equipment cost, energy demand, and eco‐friendly features, are also reviewed. The outputs of this review can be used by both the industrial sector and academia to select a suitable combination of fiber and processing technology for designing novel foods with improved functionalities that fulfill market trends and consumer needs. [ABSTRACT FROM AUTHOR]

Restoration goals in fire‐prone conifer forests include mitigating fire hazard while restoring forest structural components linked to disturbance resilience and ecological function. Restoration of overstory spatial pattern in forests often falls short of management objectives due to complexities in implementation, regulation, and available data. When historical data is available, it is often collected at plots too small to inform coarse‐scale metrics like gap size and structure of tree patches (e.g., 1 ha). Principles of ecological forestry typically emphasize overstory removal patterns that emulate those of natural disturbances. So, low‐ and moderate‐severity portions of contemporary wildfires may serve as a guide to restoration treatments where mixed‐severity fires occur. Here, we compare forest spatial pattern and configuration in 15 mechanical restoration treatments and low‐ and moderate‐severity portions of three wildfires in ponderosa pine‐dominated forests to determine how they differ in spatial pattern. We obtained satellite imagery of restoration treatments and wildfires and used supervised classification to differentiate canopy and openings. We assessed elements of landscape structure including canopy and gap cover, gap attributes, and landscape heterogeneity for each disturbance type. We found that both mechanical restoration treatments and low‐ and moderate‐severity portions of wildfires reduced forest cover, increased gap cover, and altered pattern and arrangement of gaps relative to undisturbed areas, though the magnitude of changes were greatest in the burned sites. Low‐ and moderate‐severity wildfire consistently increased landscape heterogeneity, but mechanical treatments did not. This suggests that a greater emphasis on increasing gap and patch spatial structure may make mechanical treatments more congruent with natural disturbances. Outcomes of low‐ and moderate‐severity portions of wildfires may provide important information upon which to base management prescriptions where reference data on landscape patterns is unavailable. [ABSTRACT FROM AUTHOR]

The encroachment of woody plants into grasslands, woodland, and savanna has increased markedly over the past century, prompting the use of different physical methods to remove woody plants and restore grasses. Roller‐chopping is used extensively in the Americas, but little is known about its long‐term effectiveness for restoration, and whether its effectiveness varies with the intensity of encroachment. We compared the effects of roller‐chopping, under three treatment intensities (control, single treatment, double treatment), on woody plant density, ground cover, and groundstorey plants at sites of low, moderate, and high woody plant density in a semi‐arid eastern Australian woodland over 10 years. Both single and double treatment significantly altered the size distribution of Dodonaea viscosa, which comprised more than 85% of woody plants at all sites. Thus, roller‐chopping changed the size distribution of the community from an even‐size distribution to one dominated by shorter plants, irrespective of initial encroachment level. The effectiveness of roller‐chopping was strongly site‐specific, with significant reductions in density at low‐ and high‐density sites, but no clear trend in relation to the intensity of treatment (i.e. single cf. double treatment). The effectiveness of roller‐chopping was unsustained over the long term, with the suppressive effect on woody density diminishing over time. Grass cover increased with increasing intensity of woody removal, but only at the low‐density site and with some ill‐defined, variable, and short‐term effects on plant composition. Managers should consider that the short‐term effects may not adequately reflect the long‐term results of woody plant removal using the roller‐chopper. [ABSTRACT FROM AUTHOR]

Summary: Plant architecture plasticity determines the efficiency at harvesting and plays a major role defining biomass and seed yield. We observed that several previously described transgenic genotypes exhibiting increased seed yield also show wider stems and more vascular bundles than wild‐type plants. Here, the relationship between these characteristics and seed yield was investigated. Hanging weight on the main stem of Arabidopsis plants provoked significant stem widening. Such widening was accompanied by an increase in the number of vascular bundles and about 100% of yield increase. In parallel, lignin deposition diminished. Vascular bundle formation started in the upper internode and continued downstream. AUX/LAX carriers were essential for this response. The increase of vascular bundles was reverted 3 weeks after the treatment leading to an enlarged xylem area. Aux1, lax1, and lax3 mutant plants were also able to enlarge their stems after the treatment, whereas lax2 plants did not. However, none of these mutants exhibited more vascular bundles or seed yield compared with untreated plants. Weight‐induced xylem area enhancement and increased seed yield were also observed in sunflower plants. Altogether these results showed a strong correlation between the number of vascular bundles and enhanced seed yield under a long‐day photoperiod. Furthermore, changes in the levels of auxin carriers affected both these processes in the same manner, suggesting that there may be an underlying causality. Significance Statement: The transient formation of additional vascular bundles can be induced by a short hanging weight treatment triggering the expansion of xylem area and ultimately seed yield. [ABSTRACT FROM AUTHOR]

Overabundance of woody plants in semiarid ecosystems can degrade understory herbaceous vegetation and often requires shrub reduction and seeding to recover ecosystem services. We used meta‐analysis techniques to assess the effects of fire and mechanical shrub reduction over two post‐treatment timeframes (1–4 and 5–10 years) on changes in cover and frequency of 15 seeded species at 63 restoration sites with high potential for recovery. Compared to mechanical treatments, fire resulted in greater increases in seeded species. Native shrubs did not increase, and forbs generally declined over time; however, large increases in perennial grasses were observed, suggesting that seeding efforts contributed to enhanced understory herbaceous conditions. We found greater increases in a few non‐native species than native species across all treatments, suggesting the possibility that interference among seeded species may have influenced results of this regional assessment. Differences among treatments and species were likely driven by seedbed conditions, which should be carefully considered in restoration planning. Site characteristics also dictated seeded species responses: while forbs showed greater increases in cover over the long term at higher elevation sites considered to be more resilient to disturbance, surprisingly, shrubs and grasses had greater increases in cover and frequency at lower elevation sites where resilience is typically much lower. Further research is needed to understand the causes of forb mortality over time, and to decipher how greater increases of non‐native relative to native seeded species will influence species diversity and successional trajectories of restoration sites. [ABSTRACT FROM AUTHOR]

Vegetation management practices have been applied worldwide to enhance habitats for a variety of wildlife species. Big sagebrush (Artemisia tridentata spp.) communities, iconic to western North America, have been treated to restore herbaceous understories through chemical, mechanical, and prescribed burning practices thought to improve habitat conditions for greater sage-grouse (Centrocercus urophasianus) and other species. Although the response of structural attributes of sagebrush communities to treatments is well understood, there is a need to identify how treatments influence wildlife population dynamics. We investigated the influence of vegetation treatments occurring in Wyoming, United States, from 1994 to 2012 on annual sage-grouse population change using yearly male sage-grouse lek counts. We investigated this response across 1, 3, 5, and 10-year post-treatment lags to evaluate how the amount of treated sagebrush communities and time since treatment influenced population change, while accounting for climate, wildfire, and anthropogenic factors. With the exception of chemical treatments exhibiting a positive association with sage-grouse population change 11 years after implementation, population response to treatments was either neutral or negative for at least 11 years following treatments. Our work supports a growing body of research advocating against treating big sagebrush habitats for sage-grouse, particularly in Wyoming big sagebrush (A. t. wyomingensis). Loss and fragmentation of sagebrush habitats has been identified as a significant threat for remaining sage-grouse populations. Because sagebrush may take decades to recover following treatments, we recommend practitioners use caution when designing projects to alter remaining habitats, especially when focused on habitat requirements for one life stage and a single species. [ABSTRACT FROM AUTHOR]

Changes to fire regimes have resulted in excessive shrub growth and declines in the species rich herbaceous ground layer of pyric savanna and grassland systems worldwide, including the pine flatwoods of the Southern Coastal Plain of the United States. Prescribed burning and roller chopping during growing (April-October) and dormant (November-March) seasons are management practices promoted to reduce shrub invasion and increase herbaceous plant growth in flatwoods. However, relatively little is known about the seasonal effects these activities have on shrubs and herbaceous vegetation. We assessed the effects of prescribed burning and roller chopping on herbaceous and shrub characteristics in pine flatwoods and explored how grazing may mediate these treatments. We used a paired design, with comparison made between sampling locations randomly located within treated (e.g. burned) and adjacent untreated areas. Growing season burning was more effective at reducing shrub cover and height than dormant season burning. However, shrub re-growth occurred the second year post-burn. Roller chopping and roller chopping/burning combinations led to decreases in shrub cover and height for 2 years post-treatment. Decreases in shrub density were seen on sites subject to growing season roller chopping and grazing. Decreases in herbaceous vegetation were observed following all treatments, possibly the result of grazing. If reductions in shrub density are required, growing season roller chopping in combination with grazing may be the only effective treatment. However, initial deferment from grazing following burning and roller chopping treatments may be necessary to permit re-establishment and growth of forbs and graminoids. [ABSTRACT FROM AUTHOR]

The article evaluates the effects of Fire and Fire Surrogates Network treatments on forest soil properties in the U.S. The researchers observed that pretreatment soils varied from 3.7 to 7.1 in pH and ten-fold in total inorganic N (TIN). At network scale, they found out mineral soil exposure was greater in fire-only and mechanical+fire treatments than in controls during the first posttreatment year. Based on the results, they concluded that network-wide effects of the FFS treatments on soil properties appear to have been transient and modest.

Abstract Aim: The aim of the present study was to investigate the long-term results of periodontal supportive therapy in HIV-seropositive and HIV-seronegative patients. Material and methods: Baseline examination of 18 HIV-seropositive patients (14 males and four females, median age of 29.7 years) revealed the following periodontal diagnoses: eight patients with linear gingival erythema, four patients with necrotizing periodontitis, five patients with conventional gingivitis and one patient with chronic periodontitis. In the HIV-seronegative group, out of 16 patients (12 males and four females, median age 35.5 years), one patient presented with conventional gingivitis and 15 patients with chronic periodontitis. Periodontal therapy and maintenance care consisted of supra- and subgingival removal of plaque and calculus and instruction in oral hygiene. Based on the individual patient's needs, the mechanical therapy was repeated. Results: In the test group, the mean maintenance period was 22.7 ± 9.4 months (range 11.0–37.4) and in the control group, 48.9 ± 32.0 months (range 9.3–110.8). In the test group, the mean PlI (1.1 ± 0.8) remained at the same level (1.1 ± 0.5; p = 0.73, Wilcoxon sign rank test, p < 0.05) throughout the observation period, the mean GI was reduced from 1.6 ± 0.5 to 1.4 ± 0.4 (p = 0.18), the mean PPD was reduced from 2.9 ± 0.3 to 2.8 ± 0.2 (p = 0.15) and the mean PAL (3.1 ± 0.5) remained unaltered as well (3.1 ± 0.4; p = 0.83). None of these differences was statistically significant. In the control group, PPD (3.0 ± 0.4) and PAL (3.0 ± 0.5) were significantly reduced: PPD = 2.7 ± 0.2 (p = 0.0003) and PAL = 2.9 ± 0.5 (p = 0.0034). Conclusion: In HIV-seropositive patients, attachment level can be maintained. However, oral hygiene and compliance are the key factors for this. [ABSTRACT FROM AUTHOR]