The improvement of the edge screw connection in OSB and conventional particleboard

This work presents the method for improvement of direct screw connection performance in conventional particleboard (PB) and oriented strand board (OSB). It is conceived on adhesive insertion into the pilot hole prior to embedment of the screw. The tests were carried out on the PB and OSB, both presenting interior boards and with the same nominal thickness of 18 mm. Particleboard screws of the 5 mm in diameter were inserted in the edge of the board. Pilot hole diameters were 2,5 mm and 3,0 mm and the depth of embedment was 30 mm for all tests. The chosen PVAc adhesive (type 3) with the addition of wood flour as consolidator in the range from 3-10% was inserted into pilot-hole. Tests were also obtained after consequent reassembly of the screw connection in order to examine the ratio of loss in withdrawal forces in such case. It was found that the insertion of PVAc adhesive into the pilot hole and the addition of wood flour have the positive effects on the screw withdrawal force in the tested boards.

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Edge screw withdrawal resistance in conventional particleboard and OSB: Influence of the particles type

Glasnik Sumarskog fakulteta ◽

10.2298/gsf0795109m ◽

2007 ◽

pp. 109-117

Author(s):

Jovan Miljkovic ◽

Mladjan Popovic ◽

Milanka Djiporovic-Momcilovic ◽

Ivana Gavrilovic-Grmusa

Keyword(s):

Oriented Strand Board ◽

Layer Structure ◽

Middle Layer ◽

Root Diameter ◽

Mean Values ◽

Pilot Hole ◽

Wood Particles ◽

Screw Withdrawal ◽

Insight Into

This research was based on presumption that the changes in size and shape of wood particles are expected to have certain impact on the particleboard quality in general. Since the conventional particleboard (PB) and oriented strand board (OSB) were built of the quite diverse wood particles, they present interesting specimens in the comparison tests. In this work, the influence of the wood particles type on the edge screw holding performance of conventional particleboard and OSB was investigated. Those tests were obtained with the screw diameters of 4.0 mm, 4.5 mm and 5 mm. Depth of embedment was 30 mm for all tests and with the pilot-hole diameter kept in the range of 80-90% in respect of the screw root diameter. Additional tests of the thickness density profile and tensile strength perpendicular to the surface of the board were conducted. Since the middle layer structure of the particleboard embeds the screw body, both mentioned parameters are considered important in the aspect of the quality of the edge screw holding performance. In order to have further insight into the conformation of the middle layer the image survey was obtained on the split board section presenting the surface of the middle layer. Significant differences in the SWR performance of OSB and PB was recorded at all screw diameters. For the screw withdrawal tests parameters OSB samples showed 56-73% superior mean values then conventional PB. On the other hand, the OSB showed wider dispersions of measured withdrawal forces at all screw diameters, which might present some of the problems in certain engineering and project calculations.

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Development of Oriented Strand Board (OSB) Using Phenol Formaldehyde Adhesive

Indian Journal of Forestry ◽

10.54207/bsmps1000-2014-9f64h2 ◽

2014 ◽

Vol 37 (2) ◽

pp. 157-160

Author(s):

Sagrika Behera ◽

Seema Bhatt ◽

Sneha Dobhal

Keyword(s):

Bonding Strength ◽

Oriented Strand Board ◽

Phenol Formaldehyde ◽

Solid Wood ◽

Resin Content ◽

Modulus Of Rupture ◽

Internal Bonding ◽

Poplar Wood ◽

Screw Withdrawal ◽

Internal Bonding Strength

Oriented strand board (OSB) was prepared using poplar wood with different resin content of phenol formaldehyde. It was observed that modulus of rupture and screw withdrawal of face and edge was more in oriented strand board as compare to solid wood. Internal bonding strength was very less in oriented strand board as compare to solid wood. It was also observed that most of the properties improve with increase in resin content.

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Karyopherin α-3 is a key protein in the pathogenesis of spinocerebellar ataxia type 3 controlling the nuclear localization of ataxin-3

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1716071115 ◽

2018 ◽

Vol 115 (11) ◽

pp. E2624-E2633 ◽

Cited By ~ 19

Author(s):

Anna Sergeevna Sowa ◽

Elodie Martin ◽

Inês Morgado Martins ◽

Jana Schmidt ◽

Reinhard Depping ◽

...

Keyword(s):

Spinocerebellar Ataxia ◽

Nuclear Localization ◽

Neurodegenerative Disorder ◽

Nucleocytoplasmic Transport ◽

Spinocerebellar Ataxia Type ◽

Nuclear Pore ◽

Spinocerebellar Ataxia Type 3 ◽

Nuclear Localization Signals ◽

Positive Effects ◽

Type 3

Spinocerebellar ataxia type 3 (SCA3) is a neurodegenerative disorder caused by a CAG expansion in the ATXN3 gene leading to a polyglutamine expansion in the ataxin-3 protein. The nuclear presence and aggregation of expanded ataxin-3 are critical steps in disease pathogenesis. To identify novel therapeutic targets, we investigated the nucleocytoplasmic transport system by screening a collection of importins and exportins that potentially modulate this nuclear localization. Using cell, Drosophila, and mouse models, we focused on three transport proteins, namely, CRM1, IPO13, KPNA3, and their respective Drosophila orthologs Emb, Cdm, and Kap-α3. While overexpression of CRM1/Emb demonstrated positive effects in Drosophila, KPNA3/Kap-α3 emerged as the most promising target, as knockdown via multiple RNAi lines demonstrated its ability to shuttle both truncated and full-length expanded ataxin-3, rescue neurodegeneration, restore photoreceptor formation, and reduce aggregation. Furthermore, KPNA3 knockout in SCA3 mice resulted in an amelioration of molecular and behavioral disturbances such as total activity, anxiety, and gait. Since KPNA3 is known to function as an import protein and recognize nuclear localization signals (NLSs), this work unites ataxin-3 structure to the nuclear pore machinery and provides a link between karyopherins, NLS signals, and polyglutamine disease, as well as demonstrates that KPNA3 is a key player in the pathogenesis of SCA3.

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Morphology and mechanical properties of polypropylene-wood flour composites

BioResources ◽

10.15376/biores.1.2.209-219 ◽

2006 ◽

Vol 1 (2) ◽

pp. 209-219 ◽

Cited By ~ 5

Author(s):

D. Dobreva ◽

S. Nenkova ◽

St. Vasileva

Keyword(s):

Mechanical Properties ◽

Wood Flour ◽

Tensile Tests ◽

Mechanical Tests ◽

Monochloroacetic Acid ◽

X Ray Diffraction ◽

Physical Strength ◽

Positive Effects ◽

Crystallization Degree ◽

Modified Wood

The microstructure and mechanical properties of polymer composites based on polypropylene and wood flour modified with monochloroacetic acid were investigated. Scanning electron microscopy and wide-angle X-ray diffraction were used as methods to probe the composite microstructures, while the tensile test was used to measure the physical strength. The wood flour modification was performed at different levels of monochloroacetic acid, ranging from 0.01 to 1 mol, while the modified wood flour was used as filler for polypropylene at 10, 20 and 30 wt.-%. It was found that increasing the monochloroacetic acid fraction influences the microstructure of the composites and leads to more homogeneous products. The introduction of non-modified wood flour decreases the polypropylene crystallization degree, but it improves after introduction of monochloroacetic acid. Physical-mechanical tests showed positive effects on tensile tests and Charpy notched impact strength. The new composites appear to be promising materials for construction purposes.

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Scanning Electron Microscopy of the Red Pulp of the Spleen

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006653x ◽

1971 ◽

Vol 29 ◽

pp. 496-497

Author(s):

Masayuki Miyoshi

Keyword(s):

Electron Microscope ◽

Ringer Solution ◽

Conclusive Evidence ◽

Sinus Wall ◽

Transmission Electron ◽

Type 3 ◽

Cytoplasmic Processes ◽

Splenic Red Pulp ◽

Scanning Electron ◽

Red Pulp

In spite of various attempts, conclusive evidence to explain blood passage in the splenic red pulp does not seem to have been presented. Scanning electron microscope (SEM) observations on the rabbit spleen, originally performed by us, revealed that the sinus was lined by a perforated lattice composed of longitudinally extended rod cells and transverse cytoplasmic processes, and that perforations in the lattice were continuous to the spaces among the stellate reticulum cells of the cord. In the present study the observation was extended to the dog and rat spleens, in which the cord is more developed than in the rabbit in order to clarify the possible differences in the fine structure of the sinus wall. An attempt was also made to examine the development and distribution of macrophage in the blood passage of the red pulp.Spleens were washed and fixed by perfusion with Ringer solution and then with buffered glutaraldehyde. Small tissue cubes were dehydrated with acetone, dried in air and heated with gold. Observations were made by a JEOL SEM Type-3. One air dried tissue cube was cut into small pieces and post fixed with buffered OsO4 for examination under the transmission electron microscope (TEM).

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Effects of a 6-Week Straw Phonation in Water Exercise Program on the Aging Voice

Journal of Speech Language and Hearing Research ◽

10.1044/2020_jslhr-19-00124 ◽

2020 ◽

Vol 63 (4) ◽

pp. 1018-1032

Author(s):

Chia-Hsin Wu ◽

Roger W. Chan

Keyword(s):

Acoustic Analysis ◽

Vocal Tract ◽

Exercise Program ◽

Analysis Of Covariance ◽

Elderly Subjects ◽

Control Group ◽

Perceptual Evaluation ◽

Positive Effects ◽

Aging Voice ◽

Before And After

Purpose Semi-occluded vocal tract (SOVT) exercises with tubes or straws have been widely used for a variety of voice disorders. Yet, the effects of longer periods of SOVT exercises (lasting for weeks) on the aging voice are not well understood. This study investigated the effects of a 6-week straw phonation in water (SPW) exercise program. Method Thirty-seven elderly subjects with self-perceived voice problems were assigned into two groups: (a) SPW exercises with six weekly sessions and home practice (experimental group) and (b) vocal hygiene education (control group). Before and after intervention (2 weeks after the completion of the exercise program), acoustic analysis, auditory–perceptual evaluation, and self-assessment of vocal impairment were conducted. Results Analysis of covariance revealed significant differences between the two groups in smoothed cepstral peak prominence measures, harmonics-to-noise ratio, the auditory–perceptual parameter of breathiness, and Voice Handicap Index-10 scores postintervention. No significant differences between the two groups were found for other measures. Conclusions Our results supported the positive effects of SOVT exercises for the aging voice, with a 6-week SPW exercise program being a clinical option. Future studies should involve long-term follow-up and additional outcome measures to better understand the efficacy of SOVT exercises, particularly SPW exercises, for the aging voice.

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Clinical Success Using the Audio-Visual Feedback Training for Cluttering

Perspectives of the ASHA Special Interest Groups ◽

10.1044/2019_pers-sig17-2019-0018 ◽

2019 ◽

Vol 4 (6) ◽

pp. 1589-1594

Author(s):

Yvonne van Zaalen ◽

Isabella Reichel

Keyword(s):

Visual Feedback ◽

Clinical Success ◽

Pause Duration ◽

Digital Audio ◽

Male Adolescents ◽

Feedback Training ◽

Positive Effects ◽

Speech Monitoring ◽

Adolescents And Adults

Purpose Among the best strategies to address inadequate speech monitoring skills and other parameters of communication in people with cluttering (PWC) is the relatively new but very promising auditory–visual feedback (AVF) training ( van Zaalen & Reichel, 2015 ). This study examines the effects of AVF training on articulatory accuracy, pause duration, frequency, and type of disfluencies of PWC, as well as on the emotional and cognitive aspects that may be present in clients with this communication disorder ( Reichel, 2010 ; van Zaalen & Reichel, 2015 ). Methods In this study, 12 male adolescents and adults—6 with phonological and 6 with syntactic cluttering—were provided with weekly AVF training for 12 weeks, with a 3-month follow-up. Data was gathered on baseline (T0), Week 6 (T1), Week 12 (T2), and after follow-up (T3). Spontaneous speech was recorded and analyzed by using digital audio-recording and speech analysis software known as Praat ( Boersma & Weenink, 2017 ). Results The results of this study indicated that PWC demonstrated significant improvements in articulatory rate measurements and in pause duration following the AVF training. In addition, the PWC in the study reported positive effects on their ability to retell a story and to speak in more complete sentences. PWC felt better about formulating their ideas and were more satisfied with their interactions with people around them. Conclusions The AVF training was found to be an effective approach for improving monitoring skills of PWC with both quantitative and qualitative benefits in the behavioral, cognitive, emotional, and social domains of communication.

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