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The beam stability factor (CL) is applied in construction practices to adjust the reference bending design value (Fb) of sawn lumber to consider the lateral-torsional buckling. Bending tests were carried out on 272 specimens of four wood species, namely, red meranti (Shorea sp.), mahogany (Swietenia sp.), pine (Pinus sp.), and agathis (Agathis sp.), to analyze a simply supported beam subjected to concentrated loads at several points. The empirical CL value is a ratio of the modulus of rupture (SR) of a specimen to the average SR of the standard-size specimens. The non-linear regression estimated the Euler buckling coefficient for sawn lumber beam (KbE) in this study as 0.413, with 5% lower and 5% upper values of 0.338 and 0.488. Applying the 2.74 factor, which represents an approximately 5% lower exclusion value on the pure bending modulus of elasticity (Emin) and a factor of safety, the adjusted Euler buckling coefficient (KbE′) value for a timber beam was 1.13 (0.92–1.34), which is within the range approved by the NDS (KbE′ = 1.20). This study harmonizes the NDS design practices of CL computation with the empirical results. Because agathis has the lowest ductility (μ), most natural defects (smallest strength ratio, S), and highest E/SR ratio, the agathis beam did not twist during the bending test; instead, it failed before twisting could occur, indicating inelastic material failure. Meanwhile the other specimens (pinus, mahogany, and red meranti), which have smaller E/SR ratio, higher ductility, and less natural defects, tended to fail because of lesser beam stability. This phenomenon resulted in the CL curve of agathis being the highest among the others. The CL value is mathematically related to the beam slenderness ratio (RB) and the E/SR ratio. Because the strength ratio (S) and ductility ratio (μ) have significant inverse correlations with the E/SR ratio, they are correlated with the CL value. Applying the CL value to adjust the characteristic bending strength is safe and reliable, as less than 5% of the specimens' SR data points lie below the curve of the adjusted characteristics values. [ABSTRACT FROM AUTHOR]

The mechanical properties of the structural components (i.e., columns and beams produced from engineered bamboo products), such as, bamboo scrimber (also known as parallel bamboo strand lumber, PBSL) and Laminated Bamboo Lumber (LBL), have attracted considerable attention from researchers in recent years. In previous studies, researchers reported on the stress-strain behaviour of bamboo scrimber, LBL and glue laminated bamboo under compression and proposed some empirical and semi-empirical models, based on their individual studies. However, a generic constitutive model for engineered bamboo products is still not available. The compressive stress-strain curves of bamboo scrimber and LBL are reported to show a similar behaviour with three distinct stages i.e., a linear elastic stage followed by a nonlinear plastic stage and a plateau. As part of the current study, the previously proposed models for bamboo scrimber were carefully studied and all available material test results on engineered bamboo were used to develop a generic constitutive model, based on the Ramberg-Osgood (RO) formulation considering its suitability to capture its material nonlinearity. Based on the test results, it was observed that 1% proof stress can be used in a compound RO model to predict an accurate material response for bamboo scrimber. The proposed modelling technique has also been applied to predict the compressive behaviour of LBL. This paper proposes the RO coefficients for both bamboo scrimber and LBL that can be used to develop accurate nonlinear models for engineered bamboo products. [ABSTRACT FROM AUTHOR]

Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This review critically examines the various ways in which the mechanical properties of wood have been understood. Despite the immense global importance of wood in construction, most understanding of its elastic and inelastic properties is based on models developed for other materials. Such models neglect wood's cellular and fibrous nature. This review thus questions how well models that were originally developed for homogeneous and effectively continuous materials can describe wood's mechanical properties. For example, the elastic moduli of wood have been found by many authors to depend on the size of the test specimen. Such observations are incompatible with classical elasticity theory. There is also much uncertainty about how well elastic moduli can be defined for wood. An analysis of different models for size effects of various inelastic properties of wood shows that these models only approximate the observed behaviour, and do not predict or explain the scatter in the results. A more complete understanding of wood's mechanical properties must take account of it being in some sense intermediate between a material and a structure. [ABSTRACT FROM AUTHOR]

This paper presents the first experimental study of the load-slip behaviour of aluminium-timber composite bolted connections reinforced with toothed plates. The effectiveness of the strengthening was evaluated in laboratory push-out tests. The push-out test samples consisted of laminated veneer lumber panels, aluminium alloy I-beams, and bolts (grade 8.8 10 mm × 125 mm and 12 mm × 135 mm bolts, grade 5.8 10 mm × 125 mm and 12 mm × 135 mm bolts). A group of 16 specimens had toothed plates as additional reinforcement, while 16 specimens had no reinforcement. The impact of the bolt diameter (10 and 12 mm) and bolt grade (5.8 and 8.8) on the behaviour of the connections was also analysed. The values of the ultimate load and the slip modulus for the bolted connections with grade 8.8 10 mm and 12 mm bolts and with grade 5.8 12 mm bolts reinforced by toothed-plate connectors were comparable to the values for the non-reinforced connections. This was because, in the case of grade 8.8 10 mm × 125 mm and 12 mm × 135 mm bolts and grade 5.8 12 mm × 135 mm bolts, the laminated veneer lumber (LVL) slabs split both in the reinforced and non-reinforced connections. The toothed-plate connectors reduced timber destruction in the bearing zones in the LVL slabs. However, they did not protect the LVL slabs against splitting. Therefore, the impact of the toothed plate connectors on the stiffness and strength of the bolted connections with grade 8.8 10 mm and 12 mm bolts and with grade 5.8 12 mm bolts analysed in this paper was found to be negligible. In the case of grade 5.8 10 mm bolts, the LVL slabs did not split. The mean slip modulus k0.6 of the connections with grade 5.8 10 mm bolts reinforced with toothed plate connectors was 2.9 times higher than that of the non-reinforced connections. However, the strength of the connections with grade 5.8 10 mm bolts was 1.2 times lower after reinforcing. This was because the shanks of the bolts were sheared faster in the reinforced connections than in the non-reinforced connections as a result of the bolt shanks being under the bearing pressure of the aluminium flange, the LVL slab, and the toothed-plate flange. This situation did not occur for the remaining connections because they had a higher strength (grade 8.8 bolts) or a larger diameter (12 mm), and their bolts were less prone to cutting off. The investigated load–slip curves of the reinforced bolted connections can be used for designing and numerical modelling of aluminium-timber composite beams with this type of connection. [ABSTRACT FROM AUTHOR]

Partially threaded screws are essential fasteners in timber structures, and their use in combination with hardwoods is promising in order to obtain high-performance connections. Depending on the used wood species, the load-displacement behaviour and failure mechanisms of connections change, and, in particular for high-density species, brittle failures may occur more frequently with rather low ductility of the connection. Consequently, a good understanding of the mechanical behaviour of connections at different displacement levels helps to assess where previous rules reach their limits for hardwoods. The determination of all input parameters serves as a basis for a subsequent test programme on single-shear timber-to-timber connections using beech laminated veneer lumber, birch, spruce glulam and predrilled and non-predrilled partially threaded screws. Tests on connections with one screw and groups of screws are conducted, stopped at predefined displacement stages of 5, 10 and 25 mm, and opened. A comparison of the screw deformation at the different displacement stages reveals that non-linear connection behaviour is quite different in softwood and hardwood. Essential aspects of the analysis are particularities of the load-displacement behaviour, fastener spacing, ductility of connections and the progressive plasticising of the fasteners. [ABSTRACT FROM AUTHOR]

This review aimed to analyze plastic lumber manufacturing in Brazil, a country with a large amount of natural wood, and devise strategies to boost production. No studies were found on the development and application of plastic wood in a natural wood producing country that has been significantly affected by deforestation. Wood-plastic composite lumber was used in the present study. The methodology consisted of a bibliographic review, questionnaire, SWOT and TOWS analyses. The questionnaire was completed by plastic lumber manufacturers in order to better understand the positive and negative points of the plastic wood market and production. Information on environmental, economic and technical aspects was collected to support analyses. Brazil has 11 plastic lumber producers with a production capacity of 11 × 103 metric tons, a very small amount when compared to the natural wood market. Established companies are seeking to expand domestic and foreign markets for plastic lumber, which is largely composed of polyethylene with several lignocellulosic fibers, especially wood residue for civil construction applications. According to SWOT analysis, Brazil is developing plastic lumber with several strengths (opportunities). TOWS analysis showed that in order to boost plastic lumber production, make it more competitive and reach international markets, wood and plastic residue should be aimed at manufacturing WPC. Brazil produced around 37 × 106 metric tons of wood residue and discarded approximately 16 × 106 metric tons of plastic waste in landfills, materials that could potentially be used to produce plastic lumber. There are other raw material alternatives for plastic lumber production in the agricultural sector, such as straws and grain husks. However, the country urgently needs to develop a reverse a logistics network and residue collection, as well as conduct research to channel residues to plastic lumber production. Thus, there is a greater likelihood of continued development and, consequently, attracting new markets. There is an attempt to overcome weaknesses (plastic lumber is not used for structural applications), demonstrating the need for strategies that foster technical development for structural applications. Threats (high prices and lack of fiscal incentives) require coping strategies to increase production, thereby reducing its cost. These measures could increase plastic lumber production, making it competitive enough to replace natural wood, and lead to a decline in deforestation. [ABSTRACT FROM AUTHOR]

To improve the color and surface properties of blue-stained radiata pine, heat treatment was carried out at different temperatures and times. The color change, wettability, and dynamic moisture sorption of the wood were investigated. The results showed that, as the treatment temperature and duration time increased, the surface brightness of specimens gradually decreased, and the surface color became more reddish and blueish. In addition, the contact angle of distilled water at 0 s and 18 s gradually increased as the treatment temperature and time increased, which indicated a decrease in the surface wettability. The color of the bluestained wood became more uniform with reduced surface wettability and hygroscopicity but increased sorption hysteresis after the treatment. [ABSTRACT FROM AUTHOR]

This study elucidated the mechanical performance of different connections used in orthogonal ribbed beams made of poplar laminated veneer lumber (LVL). Three types of connections (namely, U-, T-, and L-shape) were fabricated and used to connect the second beam and the middle part of a main beam to form an orthogonal rib beam. A concentrated load was applied to the intersection between the main beam and the second beam. The results showed: (1) all three types of ribbed beam connection specimens showed good connecting performance and the ductile failure, including the pull-out of partial self-tapping screws, crushing of LVL at the end of the ribbed beam, and connection failure; (2) the variation of load capacity of JD2-type specimens was approximately 3.2%, which was smaller than that of the JD1- and JD3-type specimens, slightly less than 10%; (3) the ultimate bearing capacity of a connection specimen was proportional to the number of self-tapping screws; and (4) the mechanical performance of the U-shaped connection specimens was worse than that of the L-and T-shaped connection specimens. The L-shaped connection was recommended due to its better mechanical performance, simpler configuration, and more convenient fabrication. [ABSTRACT FROM AUTHOR]

Black spruce is widely used for lumber production in Eastern Canada, and it has the potential to replace trembling aspen and paper birch for oriented strand board (OSB) manufacturing. This study evaluated the bending modulus of elasticity (MOE) and modulus of rupture (MOR), the internal bond (IB), and the thickness swelling (TS) of OSB panels made from black spruce and trembling aspen strands and how they were affected by strand geometry. All the panels met the CSA O437 (1993) standard for class O-2 properties except for the TS. The strand thickness had a significantly negative effect on the bending properties but a significantly positive effect on the IB and TS properties. The strand length had a significantly positive effect on the parallel bending properties but a significantly negative effect on the perpendicular bending properties and the IB, except for the TS. The OSB panels made from aspen obtained better bending properties, while the IB and TS properties were lower than those of the OSB black spruce panels. The results indicate that black spruce strands obtained from the Eastern Canadian softwood lumber industry are suitable for OSB production, but more work is required to reduce the TS. [ABSTRACT FROM AUTHOR]

In response to global Sustainable Development Goals (SDGs), the Chinese government has pledged to curtail increased carbon dioxide emissions beyond 2030 and to achieve carbon neutrality by 2060, thus achieving a status of an ecological civilization. Reconstituted decorative lumber, with rotary-cut (or planed) veneer from plantation or common species timber as the main raw material, has beneficial development opportunities for forestry from the perspective of an ecological civilization. This paper first discusses China's current state of ecological civilization, then researches the various life cycles of reconstituted decorative lumber using the life cycle theory and provides a reference for the Chinese reconstituted decorative lumber industry's development by analyzing progress in related fields. The eco-friendliness of reconstituted decorative lumber is explained via systematic combing, and proposals for the use and promotion of reconstituted decorative lumber in the new period are presented. Research and analysis findings show that it is necessary to comprehensively regulate the production chain of reconstituted decorative lumber based on life cycle. Research on the development and utilization of reconstituted decorative lumber needs to be strengthened. The promotion and marketing of reconstituted decorative lumber can be promoted by emphasizing its ecological significance. [ABSTRACT FROM AUTHOR]

Purpose: Polyetheretherketone (PEEK) is used to manufacture biomedical implants because it has a high strength-to-weight ratio and high strength and is biocompatible. However, the use of fused deposition modeling to print a PEEK results in low strength and crystallinity. This study aims to use the Taguchi method to optimize the printing factors to obtain the highest tensile strength of the printed PEEK object. The annealing effect on printed PEEK object and crystallinity are also investigated. Design/methodology/approach: This study determines the printing factors including the printing speed, layer thickness, printing temperature and extrusion width. Taguchi experimental design with a L9 orthogonal array is used to print the tensile specimen and carried out the tensile test to compare the tensile strength and porosity. Analysis of variance (ANOVA) is used to determine the experimental error and to determine the optimization printing parameters to obtain the highest tensile strength. A multivariate linear regression analysis is used to obtain the linear regression equation for predicting the theoretical tensile strength. An X-ray analysis is achieved to evaluate the crystalline of printed object. The effect of annealing is investigated to improve the tensile strength of printed part. An intervertebral lumber device is printed to demonstrate the feasibility of the obtained optimization parameters for practical application. Findings: Taguchi experiment designs nine sets of parameters to print the PEEK tensile specimen. The experimental results and the ANOVA present that the order in which the factors affect the tensile strength for printed PEEK parts is the layer thickness, the extrusion width, the printing speed and the printing temperature. The optimized printing parameters are a printing speed of 5 mm/s, a layer thickness of 0.1 mm, a printing temperature of 395 °C and an extrusion strand width of 0.44 mm. The average tensile strength of printed specimen with the optimized printing parameters is 91.48 MPa, which is slightly less than the theoretical predicted value of 94.34 MPa. After annealing, the tensile strength increases to 98.85 MPa, which is comparable to that for molded PEEK and the porosity decreases to 0.3 from 3.9%. X-ray diffraction results show that all printed and annealed specimens have a high degree of crystallinity. The printed intervertebral lumber device has ultimate compressive load of 13.42 kN. Originality/value: The optimized printing parameters is suitable for low-price fused deposition modeling machine because it does not involve a table at high temperature and can print the PEEK object with high tensile strength and good crystalline. Annealing parameters offer a good solution for tensile strength improvement. [ABSTRACT FROM AUTHOR]

Lumbar canal stenosis is the most common cause of lumbar spine diseases in patients over 65 years of age. This case study presents the effectiveness of prone traction, Surged Faradic current, Phonopheresis, and Core strengthening exercises on a patient with LCS (Lumbar canal stenosis). A 72-year-old male, suffering from low back pain (pain intensity -8 on Numerical pain rating scale-NPRS) and neurological claudication (symptoms appear after 2 minutes of walking was the subject of this study. Investigation revealed Ligamentum flavum (LF) hypertrophy at the lumbar level. On palpation, we found a spasm of para spinal muscles. Manual muscle testing ( MMT) of the Gluteus Maximus was grade 3. A reduced range of lumbar flexion was found. The researchers gave the patient traction in the prone position. Also worked on abdominal muscle and gluteus maximus muscle strengthening, which is generally ignored. Along with that Surged Faradic (SF) current on paraspinal muscles and phonophoresis at the site of LF thickness was also given. It was found that the patient was able to walk for 15 minutes without experiencing any symptoms after following this 8- day intervention strategy, and the level of pain was reduced to a 4 on the Numeric pain rating scale (NPRS). Based on present findings it may be concluded that the prone traction, core muscle strengthening exercises, phonophoresis for LF hypertrophy, and SF for paraspinal muscle spasm all together had tremendous effects on our patient with LCS. [ABSTRACT FROM AUTHOR]

Acetylation with acetic anhydride is well known to improve the dimensional stability and durability of wood. Veneer is appealing for acetylation because of its thin thickness, which supports a complete and even impregnation of difficult-to-treat wood species, such as beech (Fagus sylvatica L.). Unlike resin-based veneer impregnation, acetylated veneer does not require any additional curing. As a result, veneer properties are already altered prior to bonding. The compression thickness reduction in acetylated beech veneer during the manufacturing of laminated veneer lumber (LVL) utilizing 1, 3, and 6 MPa at 150 °C for 30 min is investigated in this study. The results show that acetylated beech veneer is considerably less compressible than the references. Moreover, the density of acetylated LVL at low pressure (1 MPa) is similar to the one of references, even though the compressibility is much lower. This is due to the added acetyl groups after acetylation. The reduction in compressibility is most likely caused due to a decrease in moisture content (MC) and its accompanied mechanisms. [ABSTRACT FROM AUTHOR]

Copyright of ACTA Scientiarum Polonorum Silvarum Colendarum Ratio et Industria Lignaria is the property of Poznan University of Life Sciences Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper presents the results of an experimental research performed with eight 25-mm thick oak (Quercus robur L.) lumber boards, dried in a conventional kiln. The research mainly envisaged the determination of the drying rate within different moisture content intervals, covering both the removal of free water and of bound water from wood. After drying them down to a final moisture content of 10%, all boards were subjected to a quality control procedure, where the uniformity of the final moisture content, the casehardening degree, cracks, deformations and colorations were evaluated. The results showed that, for a drying schedule with drying rates varying between 0.34%/h and 0.08%/h, no cracks occurred, but moderate/severe casehardening was present. Correlating the results from the two perspectives (drying time and drying quality) is a good instrument for evaluating the performance of a drying schedule, and further, for process optimization. [ABSTRACT FROM AUTHOR]

Although small solar photovoltaic (PV) systems avoid most soft costs, they still have a relatively high $/W value due to racking costs. In order to fulfill the promise of small-scale plug-and-play solar, a do-it-yourself PV rack design is provided and analyzed here for six criteria: (1) made from locally-accessible renewable materials, (2) 25-year lifetime to match PV warranties, (3) able to be fabricated by average consumers, (4) able to meet Canadian structural building codes, (5) low cost and (6) that it is shared using an open-source license. The open-source wood-based fixed-tilt ground-mounted bifacial photovoltaic rack design evaluated here was found to be appropriate throughout North America. Economic analysis of the bill of materials showed the racking system ranges from 49% to 77% less expensive compared to commercial proprietary racking in Canada. The racking design, however, is highly dependent on the cost of lumber that varies widely throughout the world. Even for an absolute lower-cost design in Togo due to a lower fixed tilt angle and lower loads from lack of snow, it was not found to be economic because of the relatively high cost of wood. The recent volatile lumber market warrants local evaluation from those considering the use of the open-source design. This design, however, provides for a PV rack that can be manufactured with distributed means throughout most of the world enabling more equitable access to solar energy to support a circular bioeconomy. [ABSTRACT FROM AUTHOR]

This paper presents a model for the efficiency evaluation of decision-making units comprising a network structure with undesirable intermediate measures. This model is then generalised to evaluate the efficiency of network decision-making units with triangular fuzzy data and undesirable intermediate measures. In this study, data envelopment analysis (DEA) models with fuzzy network structures and undesirable intermediate measures are considered and solved as linear triangular fuzzy planning problems. With numerical results, the application of the proposed model in the chipboard industry of wood lumber has been shown. [ABSTRACT FROM AUTHOR]

Objective: To compare the effects of lumbar sustained natural apophyseal glide and Mechanical Traction in patients with discogenic lumbosacral radiculopathy. Study Design: Quasi experimental study. Place and Duration of Study: Kanaan Physiotherapy and Spine Clinic, from Mar to Sep 2020. Methodology: A total of 44 patients were included in study in 2 groups of 22 each. Patients between ages 30-60 years having chronic radiating pain in one or both legs, patients with minimum of 25 score out of 100, on low back pain index and patients having radiculopathy were included. Exclusion criteria were history of low back pain treatment in last 90. Complications such as cancer, spine pathology and joint disease. Dice roll method was used for group allocation. Group classification was as group 1, sustained natural apophyseal glide group, and group 2, mechanical traction group. NPRS and oswestry disability index were used. Data analysis was done with SPSS version 21. Results: There is statistically significant improvement in pain as mean post treatment value for sustained natural apophyseal glide group is 2.55 ± 1.503 and for mechanical traction group is 4.05 ± 1.864, oswestry disability index and shober test results in sustained natural apophyseal glide group were also significant as compared to mechanical traction with p-value

Abstract Background One-handed backhand (OB) and two-handed backhand (TB) styles are commonly used in tennis, but only TB generates loadings on the non-dominant arm and a greater extension torque on the rear leg, leading to a greater axial torque involving rotation of the hip and trunk. The current study investigated whether those effects can further affect bone area (BA), bone mineral content (BMC) and density (BMD) in postmenopausal recreational tennis players. Methods BA, BMC and BMD of the lumbar spine, hip and distal radius were assessed using dual-energy X-ray absorptiometry in TB, OB, and swimmers’ group as a control (SG) (all participants self-reported for at least 5 years of exercise history, n = 14 per group). Muscular strength was assessed with a hand dynamometer. Among these three groups, the BA, BMC and BMD of distal radius and muscle strength were assessed using one-way ANOVA, and those of the lumbar region and the hip joint were tested by one-way ANCOVA. Results TB showed higher BMC and BMD for both lumbar spine and femoral neck than SG (all, p

In rural, isolated areas, sawmills are often equipped with one or more small-capacity hand-fed band saws. Even in this situation, the productivity of the band saw must be viewed through the factors that influence it, namely the characteristics of logs and the optimization of the stages and activities carried out. Therefore, time consumption, the structure of working time and the recovery rate in sawing logs into lumber provide important information for users. The structure of the sawing operation for a work team made up of an operator and an assistant was divided into six work stages. The sawing pattern used involves sawing the log up to approximately half of the diameter, then rolling the log with 180° and continuing the sawing, aiming to obtain lumber with a thickness of 40 and 50 mm from the central part of the log. The productivity was 2.45 m3·h−1, the recovery rate was 70.84% and the working time real-use coefficient was 0.37. Research has highlighted the positive correlation between working time and the middle diameter of the logs (R2 = 0.84). The feeding speed was also determined along with the quality of cuts, which was expressed by the thickness uniformity of the lumber and the presence of cutting teeth traces on the newly created surfaces.

To further understand the rolling shear (RS) failure of cross-laminated timber (CLT), acoustic emission (AE) technology was employed to evaluate the RS strength of CLT transverse layer, which includes three wood species (spruce-pine-fir dimension lumber, fast-growing poplar and Chinese fir). The steel-wood-steel (SWS) specimens were prepared and tested under out-of-plane bending shear and in-plane compression shear tests. By means of characteristic parameter and clustering analysis, the relevance of AE parameters and crack during RS failure was further studied. The results suggested that species had great influence on the RS strength and the fast-growing poplar had the highest RS strength. The effect of testing methods was not significant, although the mean RS strength by compression shear test was 15 %-21 % higher than that tested by bending shear test. The energy release process of RS failure could generally be divided into "gentle period", "steady period" and "steep period". Based on ring-down counting, "fracture precursor characteristic area" could be identified before failure. In addition, the cluster analysis combined with risetime/amplitude and average frequency (RA-AF) analysis shown that the signal cluster of low amplitude in most specimens mainly represented tensile cracks, while the signal clusters of middle and high amplitude represented the cracks of tensile-shear composite. The failure in bending shear specimens was mainly caused by tensile cracks. The shear cracks, however, dominated in compression shear specimens. • The process of acoustic energy release can be generally divided into three stages. • Cluster 1 and 2 represent appearing and developing of cracks, respectively. • Failure mode in bending and compression shear specimens is tensile-shear composite. • The dominant types of failure are different under two different test methods. [ABSTRACT FROM AUTHOR]