Wooden Cubes Research Articles

Different grasping experiences affect mapping effects but not correspondence effects between stimulus size and response location.

The so-called spatial-size association of response codes (SSARC) effect denotes that humans respond faster and more accurately with a left response to physically small stimuli and a right response to physically large stimuli, as compared to the opposite mapping. According to an application of the CORE principle to the SSARC effect, the habit to grasp larger/heavier objects with one's dominant hand and smaller/lighter objects with one's non-dominant hand creates spatial-size associations. We investigated if grasping habits play a causal role in the formation of spatial-size associations by testing if the mapping of a preceding object-grasping task affects the size of the SSARC effect in subsequent choice-response tasks with keypress responses. In the object-grasping task, participants were instructed to grasp wooden cubes of variable size either according to a compatible (small-left; large-right) or according to an incompatible (small-right; large-left) mapping. In the choice-response tasks, participants responded with left or right keypresses to the size or color of a small or large stimulus. The results showed that participants with the compatible mapping in the object-grasping task showed a larger SSARC effect in the size discrimination task, but not in the color discrimination task, than participants with the incompatible mapping in the object-grasping task. Results suggest that a short period of practice with different size-location mappings can modulate size-location links used for controlled S-R translation, but not links underlying automatic S-R translation. In general, the results support the hypothesis that grasping habits play a causal role in the formation of spatial-size associations.

Assessment of Flavor Compounds in Blended Malt Whisky Aged with Acacia, Cedar and Oak Wood Using Liquid Chromatography Hyphenated to Electrospray Ionization and Tandem Mass Spectrometry (LC-ESI-MS/MS)

Selected flavor compounds from wood were quantified, with liquid chromatography hyphenated to electrospray ionization and tandem mass spectrometry (LC-ESI-MS/MS), in four samples of base spirit matured with acacia, cedar, virgin oak, and used port wine oak wood cubes and the results were used to describe and differentiate their different wood congener profiles. ESI-MS/MS parameters were optimized in terms of capillary voltage, cone- and desolvation gas flow, source- and desolvation temperature, cone voltage, and collision energy. The method was validated in terms of linearity (R2 > 0.995), limit of detection, limit of quantification, recovery, and repeatability. One-way analysis of variance (ANOVA) showed that for most compounds there were no significant differences (α = 0.05) between seven to 30 days of aging plus a heat treatment at 40 °C, but wood type did significantly influence the wood congener profile. Principal component analysis discriminated the spirits based on relative amounts of wood congeners extracted, and the chemical profile. Aging with cedar wood led to a less pronounced chemical profile, not very distinct from the base spirit. Aging with acacia and virgin oak wood produced a second chemical profile with relatively higher levels of synapaldehyde, syringaldehyde, scopoletin, and coniferyl aldehyde. Aging with port oak wood produced a third chemical profile with relatively higher levels of 5-HMF, gallic acid, furfural, vanillic acid, and syringic acid.

Physicochemical and Biochemical Changes in Cocoa during the Fermentation Step

The physicochemical and biochemical changes during the fermentation of four clones and two native varieties of Theobroma cacao L. were studied. Fermentation was performed in traditional wood cubes. During fermentation, the cotyledon pH decreased, and the temperature increased to more than 10 °C above the ambient temperature (47 °C). The fermentation index (FI) increased in the clones C1, C4, C8, C9, and Guayaquil (G) to close to one at 120 h of fermentation. For the FI of the cocoa Criollo (Cr), a value of 2.5 was proposed according to the spectrophotometric scan performance. The total polyphenol content increased in all the samples from 21 (C8) to 70 (Cr) % in a comparison of the TPC at T0 and T120, respectively. The total flavonoid content increased from 16 (C8) to 51% in Guayaquil (G) during the fermentation period. In the case of the methylxanthines, such as theobromine and caffeine, both quantities decreased. The theobromine content decreased in all the samples from 6 (G) to 31% (C8). The caffeine content decreased in all the samples from 3% in Cr to 25% in C1 and G after fermentation. The antioxidant capability did not change after 120 h of fermentation, and the amount of methylxanthines did not affect the antioxidant potential of the fermented cocoa. The FTIR scan of the fat-free cocoa showed significant differences between the unfermented and fermented beans, and several peaks assigned to carbohydrates and proteins decreased.

Inter‐basin comparison of wood flux using random forest modelling and repeated wood extractions in unmonitored catchments

AbstractPredicting wood flux (i.e., wood piece number per time interval) or discharge (metre cubes of wood per second) in rivers is crucial for adequate integrated river management that balances risk assessment and ecological improvement. To enhance our understanding of the transport mechanisms of wood and assess their effects in various geographical contexts, it is necessary to conduct inter‐basin comparative studies and preliminary modelling. The wood flux of two river basins was analysed using video monitoring and random forest predictions based on hydrological drivers. The wood flux dynamics of the Ain and Allier rivers were both compared and contrasted. Although there was shared wood transport hysteresis, hourly wood flux, relative critical flow discharges of wood transport and certain hydrological factors exhibited differences between the two river basins. As a next step, the two random forest models, which were trained previously, were applied to predict wood flux and then wood discharge in a third river (the Rhône), in order to estimate a wood volume export, which can be compared with the wood volumes extracted over a series of a few monthly periods in the Génissiat reservoir. By using the random forest modelling, it is possible to estimate the volume of wood on the Rhône river. Despite the absence of any training data, there is a noticeable correlation, however, the estimated volumes were significantly overestimated. To resolve this issue, a correction factor was applied, accounting for disparities in wood recruitment dynamics between the Rhône basin and the training river basins. It was found that high flow events are underestimated, emphasizing the importance of incorporating local annotations and additional parameters in training the random forest model. Accurately predicting wood flux is important for integrated watershed management, but field observations are still lacking for validation and process‐based understanding.

Sulfuryl Fluoride Fumigation as a Quarantine Treatment for the Control of Reticulitermes speratus Kolbe (Blattodea: Rhinotermitidae) in Wood.

High-risk termites in wood imported to the Republic of Korea are currently treated with methyl bromide (MB), which has ozone-depleting properties and is highly toxic. This study evaluated the effectiveness of sulfuryl fluoride (SF) as a quarantine treatment against Reticulitermes speratus Kolbe (Blattodea: Rhinotermitidae) in wood, along with its wood sorption and penetration capacity. The LCt50 and LCt99 values for SF were 30.87 and 42.53 mg h/L at 23 °C and 151.62 and 401.9 mg h/L at 5 °C, respectively. The SF Ct values did not significantly differ between dry and wet wood at loading ratios of 10%, 30%, and 50% at both 5 °C and 23 °C (p > 0.05). In a closed wooden cube, the LCt50 and LCt99 for SF for R. speratus were 31.59 and 53.34 mg h/L, respectively, indicating an excellent wood penetration ability. SF caused 100% termite mortality with a 90% loading ratio in the scale-up trials (500 L). The SF concentration during ventilation decreased below the threshold limit value (TLV) of 5 ppm within 30 min, confirming that the working conditions were safe. This study provides a basis for the use of SF as an alternative to MB for the treatment of termites in wood.

The BE-UJI hand function activity set: a reduced set of activities for the evaluation of the healthy and pathological hand

BackgroundHand kinematics during hand function tests based on the performance of activities of daily living (ADLs) can provide objective data to determine patients’ functional loss. However, they are rarely used during clinical assessments because of their long duration. Starting with the 20 Sollerman Hand Function Test (SHFT) tasks, we propose identifying a reduced set of ADLs that provides similar kinematic information to the original full set in terms of synergies, ranges of motion and velocities.MethodsWe followed an iterative method with the kinematics of 16 hand joints while performing the 20 ADLs of the SHFT. For each subject, ADLs were ordered according to their influence on the synergies obtained by means of a principal component analysis, the minimum number of ADLs that represented the original kinematic synergies (maximum angle of 30° between synergies), and the maintained ranges of joint movements (85% of the original ones) were selected for each subject. The set of the most frequently selected ADLs was verified to be representative of the SHFT ADLs in terms of motion strategies, ranges of motion and joint velocities when considering healthy subjects and Hand Osteoarthritis patients.ResultsA set of 10 tasks, the BE-UJI activity set, was identified by ensuring a certain (minimum) similarity in synergy (maximum mean angle between synergies of 25.5°), functional joint ranges (maximum differences of 10°) and joint velocities (maximum differences of 15°/s). The obtained tasks were: pick up coins from purses, lift wooden cubes, pick up nuts and turn them, write with a pen, cut with a knife, lift a telephone, unscrew jar lids and pour water from a cup, a jar and a Pure-Pak. These activities guarantee using the seven commonest handgrips in ADLs.ConclusionThe BE-UJI activity set for the hand function assessment can be used to obtain quantitative data in clinics as an alternative to the SHFT. It reduces the test time and allows clinicians to obtain objective kinematic data of the motor strategies, ranges of motion and joint velocities used by patients.

Evaluating the viscoelastic shear properties of clear wood via off-axis compression testing and digital-image correlation

AbstractHighly anisotropic materials like wood and unidirectional polymer composite structures are sensitive to shear deformations, in particular close to fixed joints. Large wooden structures in buildings and, e.g. wind-turbine blades, are designed to last for decades, and hence are susceptible to unwanted creep deformations. For improved structural design, the shear-creep properties of the material are needed. These are rarely available in the literature, possibly because of technical difficulties to achieve a well-defined shear-stress state in test specimens. For cost-efficient testing, this goal of a pure stress state necessarily needs to be compromised. In the present study, we propose a simple test method based on uniaxial compression on wooden cubes, but is equally applicable for fibre composites. The viscoelastic shear properties of Norway spruce (Picea abies) under off-axis creep compression tests have been characterised in all three directions. The tests are performed in a controlled climate chamber and the creep strains are captured using digital-image correlation.

3D Printed Prosthetic Robot Arm with Grasping Detection System for Children

Prosthetic robot arms have been an alternative replacement for upper limb-related disability, especially among children as it helps them perform regular activities such as holding tools, eating, and drinking. This research aims to develop a 3D prosthetic robot arm using SolidWorks and 3D printer, using a low-cost and straightforward mechanism for children. This paper proposes a close loop control system with position control for the prosthetic robot arm to achieve an appropriate grasping force focusing on solid-shaped objects using PID control. The PID controller controls the system's response to perform in the most efficient path. Force-sensitive resistors (FSR) are attached to all fingers to measure the grasping force acting on objects with different surfaces, dimensions, and weights. The controller results showed improvement in the overshoot percentage of 0.902%, as overshoot is essential in preventing the grasped object's deformations. The analysis of the experiment shows that the mean grasping force and static coefficient friction of each object are different regardless of the material the object is made of and the object's mass. For example, a cube-shaped object made of wood requires 0.5288 N of grasping force to grasp the object firmly compared to a plastic-made cube that only requires 0.3245 N to hold the cube. On the other hand, the static coefficient friction for the wood cube is 3.1708 and 0.4725 for the plastic cube. Further research can be done by designing the prosthetic robot arm with independent motorized and multi-degree movement of fingers.

How to pretest non-psychometric tools: A field research example of exploring the acceptability, face validity and utility of Emotioncubes: A novel tool to support therapeutic working with emotions

Working with emotion is central to therapeutic approaches. However, there are few appropriately tested creative tools designed for this purpose. There is also no evidence-based testing guidance for counseling tools available outside of the psychometric field. Therefore, this study combined cognitive pretesting with in-depth qualitative interviews to explore the acceptability, face validity and utility of Emotioncubes -12, three-dimensional wooden cubes that support the therapeutic exploration of emotion. This testing approach revealed performance insights that would not be established via alternative methods such as premature case studies or randomized trial. The findings also offer guidance for others seeking to test such tools.

Experimental and numerical study on the withdrawal behaviour of lag screws on wood side-grain

In wood connections using lag screws as mechanical fasteners, the tension force transfer mechanisms occur through the interaction between the screw threads and the wood surface. It is necessary to understand the screw withdrawal behaviour in order to make a simple but representative interaction model instead of modeling the geometry of the screw threads. This study aims to evaluate experimentally and numerically the withdrawal failure modes, stiffnesses, and capacities of lag screws on wood side-grain. The experiment is conducted on the withdrawal of lag screws with different diameters and penetration lengths in Meranti wood cubes. The numerical analysis is carried out using ABAQUS finite element program and compared with the experimental results. Both experimental test and numerical analysis results show that the failure of all specimens occurred in the wood around the hole, not due to the slip between the lag screw and the wood's surface, which validates the proposed interaction model between the screw and the wood’s surfaces. The wood's effective material stiffness and strength in numerical models are obtained by matching the load-displacement curves with the experiment results. The effective Fy value range is between 18.5 MPa - 24 MPa, while the effective E value range is between 115 MPa - 680 MPa.

Influence of size and temperature on the auto-ignition characteristics of solid beech and spruce wood

The influence of size and temperature on the heating and auto-ignition of beech (fagus sylvatica) and spruce (picea abies) wood cubes were studied. Experiments were conducted in a furnace at five isothermal temperatures (240 °C, 270 °C, 300 °C, 330 °C and 360 °C) with four cube sizes (5 mm, 10 mm, 15 mm and 20 mm). Temperatures inside the cubes were recorded with thermocouples (TC). Arising temperatures from the experiments were compared to mass-losses and exothermic reactions measured with simultaneous thermal analysis (STA). While heating up isothermal phases at approx. 360 °C can be seen in the temperature curves due to ongoing pyrolysis. After pyrolysis, a combination of internal heating and heterogenous oxidation reactions on the surface lead to ignition and combustion. Differences in chemical composition between beech and spruce are the cause for exothermic reactions at lower temperatures. Bigger samples tend to ignite at lower temperatures due to lower surface to volume ratio and a larger reactive surface.

Investigating the effect of preheating conditions and size effect on asphalt blending in recycled asphalt mixture: New approach based on artificial aggregate and laser scanning confocal microscopy

• The influence of preheating conditions and size effect on the blending phenomena were evaluated through 3D-FIT method. • The difference of asphalt blending between virgin and RAP aggregate were also investigated. • The longer curing time does not mean better blending, which exists a limited value and an optimal storage time. • Smaller sizes of virgin aggregate can mobilize more active reclaimed asphalt from RAP aggregate. The blending phenomena between virgin and reclaimed asphalt is a significant concern in asphalt paving, which play a crucial role in the final performance of the recycled asphalt mixture. Although past studies broadly discussed the asphalt blending by various test methods, the blending process holds 3D features due to the different aging degrees of reclaimed asphalt and different dispersity of virgin asphalt. The three-dimensional observation in the asphalt blending is still limited. Simultaneously, many factors (e.g., preheating temperature and time, transportation temperature, storage time, and aggregate gradation) will affect the blending process. The relationships between those factors and the blending phenomena are still unknown. To overcome this problem, this paper proposed a 3D fluorescence image method by laser scanning confocal microscopy and artificial aggregate. The artificial aggregate in the wooden cube form was used to analyze the blending process of virgin and RAP aggregate in three-dimension, respectively. Meanwhile, preheating conditions and size effect on the blending phenomena were also evaluated. The results indicate that temperature presents a more significant influence on the blending than the curing time. A longer curing time does not mean better blending, which exists a limited value and an optimal storage time. Compared to RAP aggregate, more homogeneous blending occurred on virgin aggregate after 2 h curing time at 180 °C, so the blending process on virgin aggregate should also be considered by researchers. This study may help to explain the production of recycled asphalt mixture and understand the blending phenomena in asphalt paving.

Product distribution from pyrolysis of large biomass particle: Effects of intraparticle secondary reactions

Thermochemical conversion provides promising approaches for utilization of agroforestry residues as energy sources in rural areas, such as decentralized biomass combustion and gasification. Understanding of the pyrolysis characteristics are crucial for the design of reactors and optimization of working conditions, but in these scenarios, utilization of centimeter-sized large fuel particles will bring challenges in predicting the evolution of pyrolytic products owing to the intraparticle secondary reactions. In this work, the product distribution of biomass pyrolysis was investigated in wide ranges of temperatures and particle sizes, and special attention was paid to the pyrolysis of centimeter-sized fuel particles under medium to high temperatures (500 °C – 900 °C). The yields of solid/liquid/gas-phase products were quantified, and the composition of tar and gas products were qualitatively and quantitatively evaluated, aiming at illustrating the effects of intraparticle secondary reactions. The results have shown that the differences between the product distribution of sawdust (<1 mm) and centimeter-sized wood cubes were significant over the whole temperature range, but the differences between wood cubes with varying sizes (1 cm, 1.5 cm and 2 cm) were dependent with the external temperature, indicating that the extent of intraparticle secondary reactions was simultaneously determined by external temperature and particle size. The evolution of tar composition indicated that the intraparticle secondary reactions could be divided into two distinctive steps. Increasing the particle size would firstly result in fast consumption of primary tar species and emergence of secondary tar species, while the second step would lead to the formation of simple phenols and aromatics, and large quantities of PAHs were released for centimeter-sized fuel particle under high temperatures (≥800 °C). Kinetic analysis further revealed that the first step was mainly transport controlled and sensitive to particle size, while the second step was jointly controlled by kinetics and transport, which appeared to be significant only if the particle size was large and simultaneously the temperature was sufficiently high.

Effects of spacing on flaming and smoldering firebrands in wildland–urban interface fires

Firebrand (ember) attack has been shown to be one of the key mechanisms of wildfire spread into wildland–urban interface communities. After the firebrands land on a substrate material, the ignition propensity of the material depends on not only the attributes (e.g. shape, size, and numbers) but also the distribution of the firebrands. To help characterize this process, this study aims to investigate the effects of gap spacing on the burning behaviors of a group of wooden samples. Experiments are conducted using nine wooden cubes, 19 mm on each side. These samples are arranged in a 3 × 3 square pattern on suspension wires and are ignited by hot coils from the bottom surface. The gap spacing (s) between the samples varies in each test (ranging from 0 to 30 mm). After ignition, the samples are left to burn to completion. The burning process is recorded using video cameras. Sample mass loss and temperatures are monitored during the flaming and smoldering processes. The results show that the flame height and the sample mass loss rate have non-monotonic dependencies on the gap spacing. When the gap spacing reduces, the flame height and the mass loss rate first increase due to enhanced heat input from the adjacent flames to each sample. When s ≤ 10 mm, flames from individual samples are observed to merge into a single large fire. As s further decreases, the air entrainment at the flame bottom decreases and the flame lift-off distance at the flame center increases, resulting in an increased flame height, decreased flame heat feedback to the solid samples, and a decreased mass loss rate. The decreased mass loss rate eventually leads to a decrease in the flame height as well. The gaseous flame height is correlated to the solid burning rate. The correlation generally follows previous empirical equations for continuous fire sources. For the smoldering combustion, compared to a single burning sample, the smoldering temperature and duration significantly increase due to the thermal interactions between adjacent burning samples. To help interpret the results of the burning experiments, thermogravimetric analysis is also performed in air and nitrogen, resulting in heating rates ranging from 10 to 100 K/min.

Experiments on snowdrifts around two adjacent cube models based on a combined snow-wind facility

This study conducted experiments on the wind-induced snow drifting around two adjacent cube models, using artificial snow in an open air snow-wind combined experimental facility constructed at the Harbin Institute of Technology (HIT). In particular, 20 experiments were conducted on two adjacent cubes with three different wind directions, three different wind speeds, and four different spacings. They were compared with contrast experiments with a single cube under the same inflow condition. The cube models were two wooden cubes having dimensions of 0.5 × 0.5 × 0.5 m. The drift process of natural snowfall was simulated by scattering snow particles. After snowfall for 25 min in each experiment, the snowdrifts were measured by surveying approximately 300 points around the cubes. Contour maps of the normalized snow depths were drawn and analyzed. The experiments show that the wind direction and speed have a certain influence on a snowdrift. Based on the wind-snow movement mechanism, the relationship between the snowdrift pattern around two cubes and the snowdrift pattern around a single cube was explored. Under the same condition, the snowdrift pattern around the multiple cubes can be deduced from the snowdrift pattern around the single cube. The snowdrift pattern around the downstream cube depends on its spatial position relative to the upstream cube. Moreover, the snowdrift between two adjacent cubes seems to be dependent on a funneling effect.

Bioefficacy of plant oils applied through wooden cube impregnation against pulse beetle, Callosobruchus maculatus (F.) in green gram

Aim: To assess the bioefficacy of plant oils against pulse beetle, Callosobruchus maculatus (F.) in green gram through wooden cube impregnation. Methodology: Bioefficacy of plant oils viz; clove, sweet flag, eucalyptus, orange, cedar wood and neem at two doses, i.e., 0.5 ml and 1.0 ml dispensed through a small wooden cube was assessed against the pulse beetle in green gram. The oils except neem are essential oils. A wooden cube impregnated with plant oil was placed over the grain surface and ten pairs of adult insects were released into each treatment. Data on oviposition, adult emergence and grain damage was recorded in each treatment. Insect mortality due to fumigant effect of plant oil at 0.5 ml per cube was also observed. Results: There was no oviposition by pulse beetles in clove, sweet flag, and eucalyptus oil treatments at 0.5 ml against the untreated control which recorded 14 eggs/100 grains. Consequently, no population buildup was observed in clove, sweet flag, eucalyptus and orange oil treatments after 120 days. A total of 2313.33 adults emerged from the untreated green gram inflicting 46.67 percent grain damage. In fumigant toxicity test, hundred per cent mortality of pulse beetle adults was observed with orange oil in 48 hr of treatment and with eucalyptus oil in 72 hr at 0.5 ml. The results indicated that the plant oils showed strong oviposition deterrence as well as insecticidal activity against the pulse beetle. Thus, application of essential oils through a wooden cube was found highly effective to keep away the pulse beetles. Interpretation: Essential oils of clove, sweet flag, eucalyptus and orange when applied through wooden cube impregnation at a dose as low as 0.5 ml showed strong oviposition deterrence and insecticidal activity against pulse beetle. The insecticidal activity of oils can be attributed to the fumigant action and can be used effectively to prevent pulse beetle infestation in grain legumes.

Effect of lignocellulosic materials and chlorpyrifos pesticide on secretion of ligninolytic enzymes by the white rot fungus – Stereum ostrea

The present study compared the effect of chlorpyrifos on secretion of ligninolytic enzyme by the white rot fungus – Stereum ostrea grown in the presence and the absence of Tectona grandis cubes under submerged liquid conditions. Significantly higher yields of laccase and manganese peroxidase to the extent of 164.30 and 59.28 U/ml were registered in control containing only teak wood cubes than in the culture on combination of cubes and chlorpyrifos with 111.65 and 47.24 U/ml, respectively on 10th day of incubation. Reversed pattern in lignin peroxidase secretion with peak values on 6th day of incubation was noticed in the culture of S. ostrea immobilized on Tectona grandis cubes under influence of chlorpyrifos. Under free state conditions, significantly higher secretions of laccase (125.33 U/ml) and manganese peroxidase (53.60 U/ml) occurred in chlorpyrifos-amended medium than in the medium devoid of chlorpyrifos on 10th day incubation. Under moderate shaking conditions, supplementation of wheat bran alone at 3% level to the medium resulted in enhanced (3–5 folds) secretions of laccase, manganese peroxidase and lignin peroxidase by S. ostrea in medium free of wheat bran on 12th and 10th day of incubations. The presence of chlorpyrifos in addition to wheat bran in the medium further raised production of ligninolytic enzymes – laccase, MnP and LiP to the level of 311.78, 130 and 3 U/ml respectively on the 12th (higher LAC and MnP secretions) and 10th (higher LiP secretions) day of incubations. Our data in the present study suggest that secretion of ligninolytic enzymes by the culture is dependent on the nature of lignocellulosic material used in the study and secretion of higher titers of ligninolytic enzymes on cubes of Tectona grandis in the absence of chlorpyrifos rather in the presence of chlorpyrifos occurred. For executing microbial applications, it is critical to understand how lignocellulosic materials and toxic xenobiotic pesticides interact with white rot fungi and possible role of ligninolytic enzymes in the bioremediation process.

Method for maintaining adult solitary bee Centris analis under laboratory conditions

Abstract Although solitary bees represent at least 70% of bee species, most ecotoxicological studies on bees focus on social species and there are only a few species of solitary bees. One of the challenges in developing toxicological studies on solitary bees is the lack of protocols for maintaining these species under laboratory conditions. This study aimed to develop a method to maintain adult individuals of the solitary bee Centris analis under controlled conditions. Six models of cages with adaptations for food identification and resting areas were tested based on cages used for Apis mellifera and Osmia bicornis. With this in mind, we placed one individual of Centris analis in each cage and set the temperature at 28°C. Cage models with survival higher than 50% of individuals were used to measure the influence of photoperiod, training and concentration of food in bee adaptation and longevity. Cages containing a wood cube and an artificial fabric flower supported the survival of 75% of captive bees for longer than 30 days at 28°C. Bee survival rate was higher in the absence of photoperiod. This work showed the importance of an acclimatization period of 3 days for C. analis and described a feasible method for future studies evaluating the effects of pesticide effects on solitary bees under laboratory conditions.

High Permeability of Boron along the Transverse Direction of Wood under High-Voltage Electrostatic Field (HVEF) Treatment

Permeability of wood preservative is one of the most significant factors for protection of wood construction. Anisotropic flow permeability was involved in different directions of wood with higher flow resistance in the transverse and lower longitudinal directions. In this study, boron acid solution was brushed onto the tangential section of air-dried wood cubes and boron penetration along wood transverse direction was investigated under free diffusion, vacuum and HVEF treatments. Multi-scale boron distribution, FTIR measurement, leaching property, mechanical properties and fungistatic characteristic were investigated for free diffusion, vacuum and HVEF treated samples respectively. The results revealed that boron exhibited high permeability along the transverse direction with the penetration depth of ≈35 mm for HVEF treated samples and ≈1 mm for free diffusion and vacuum treated samples. For HVEF treated samples, no significant decrease of hardness, compression modulus of elasticity and strength were found in the treated samples. Better fungistatic characteristic was showcased in HVEF treated samples exposed to white rot fungi. Thus, HVEF treatment has a positive effect on boron permeability and the improvement of penetration depth of preservatives hence playing a significant role in wood protection and prolonging the service life of wood construction.

Field Demonstration of Heat Technology to Mitigate Heat Sinks for Drywood Termite (Blattodea: Kalotermitidae) Management.

Simple SummaryThe West Indian drywood termite, Cryptotermes brevis poses a significant economic threat in Hawaii, the southeast portion of continental United States, and throughout tropical and subtropical regions worldwide. Heat treatment is among the nonchemical options to manage them. A typical heat treatment may not be able to provide a complete kill of drywood termites due to the presence of difficult-to-heat areas. To mitigate this effect, studies were conducted in drywood termite-infested condominiums in Honolulu, Hawaii, where either a standard heat treatment performed by a heat remediation company or improved heat treatment methods were used. For improved treatments, heated air was directed into the drilled bases of infested cabinets for better heat penetration. Eight temperature sensors showed that sufficiently high heat was recorded at difficult-to-heat areas, including inside thick wooden cubes, for 120 min, with target temperatures of above 46 °C or 50 °C capable of killing drywood termites. A pre-treatment and a 6-month posttreatment inspection were performed to monitor termite inactivity using visual observations and by recording the numbers of spiked peaks on a termite detection device. The data showed no termite activity in improved heat treatment condominiums at 6-month posttreatment. Guidelines for the improved heat treatment are proposed.With heat treatments to control drywood termites (Blattodea: Kalotermitidae), the presence of heat sinks causes heat to be distributed unevenly throughout the treatment areas. Drywood termites may move to galleries in heat sink areas to avoid exposure to lethal temperatures. Our studies were conducted in Crytotermes brevis-infested condominiums in Honolulu, Hawaii to reflect real-world condominium scenarios; either a standard heat treatment performed by a heat remediation company, or an improved heat treatment was used. For improved treatments, heated air was directed into the toe-kick voids of C. brevis infested cabinets to reduce heat sink effects and increase heat penetration into these difficult-to-heat areas. Eight thermistor sensors placed inside the toe-kick voids, treatment zone, embedded inside cabinets’ sidewalls, and in a wooden cube recorded target temperatures of above 46 °C or 50 °C for 120 min. Pre-treatment and follow-up inspections were performed at 6 months posttreatment to monitor termite inactivity using visual observations and by recording the numbers of spiked peaks on a microwave technology termite detection device (Termatrac). In improved treatment condominiums, significantly higher numbers of spiked peaks were recorded at pre-treatment as compared to 6 months posttreatment. Efficacious heat treatment protocols using the improved methods are proposed.