Significant influence of lignin on axial elastic modulus of poplar wood at low microfibril angles under wet conditions

Abstract Wood is extensively used as a construction material. Despite increasing knowledge of its mechanical properties, the contribution of the cell-wall matrix polymers to wood mechanics is still not well understood. Previous studies have shown that axial stiffness correlates with lignin content only for cellulose microfibril angles larger than around 20°, while no influence is found for smaller angles. Here, by analysing the wood of poplar with reduced lignin content due to down-regulation of CAFFEOYL SHIKIMATE ESTERASE, we show that lignin content also influences axial stiffness at smaller angles. Micro-tensile tests of the xylem revealed that axial stiffness was strongly reduced in the low-lignin transgenic lines. Strikingly, microfibril angles were around 15° for both wild-type and transgenic poplars, suggesting that cellulose orientation is not responsible for the observed changes in mechanical behavior. Multiple linear regression analysis showed that the decrease in stiffness was almost completely related to the variation in both density and lignin content. We suggest that the influence of lignin content on axial stiffness may gradually increase as a function of the microfibril angle. Our results may help in building up comprehensive models of the cell wall that can unravel the individual roles of the matrix polymers.

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Pengaruh Kecerdasan Emosional Dan Ethical Sensitivity Terhadap Persepsi Etis Mahasiswa Sebagai Calon Akuntan

JURNAL EKSPLORASI AKUNTANSI ◽

10.24036/jea.v2i4.322 ◽

2020 ◽

Vol 2 (4) ◽

pp. 3840-3857

Author(s):

Ridho Irmas Ferdian ◽

Mayar Afriyenti

Keyword(s):

Emotional Intelligence ◽

Linear Regression Analysis ◽

Sampling Technique ◽

Multiple Linear Regression Analysis ◽

Accounting Students ◽

Ethical Sensitivity ◽

Ethical Perceptions ◽

City College ◽

The Individual ◽

Positive Effect

This study wanted to determine the ethical perceptions of students from the individual side of accounting students at FE UNP, namely from the emotional intelligence and ethical sensitivity of students. The author makes students the object of research because an accountant's ethical perceptions can also be influenced by several factors. One of them is external factors, namely the environment. The environment affects the formation of a person's character so that it affects their behavior. This research is classified as a causative research. The population used in this study were accounting students at the Padang City College. Samples were taken using purposive stratified sampling technique. Where is the sampling by taking samples of people selected by the author according to specific characteristics and certain characters. The analysis used in this study is multiple linear regression analysis used in this study is to use the SPSS 21 computer program. . The results of this study are that emotional intelligence has a positive effect on students' ethical perceptions as prospective accountants and ethical sensitivity has a positive effect on students' ethical perceptions as prospective accountants.

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ANALISIS PERSEPSI PETANI TERHADAP PROGRAM KAWASAN RUMAH PANGAN LESTARI DI KAMPUNG DOSAI DISTRIK SENTANI BARAT KABUPATEN JAYAPURA PROVINSI PAPUA

SEPA Jurnal Sosial Ekonomi Pertanian dan Agribisnis ◽

10.20961/sepa.v15i2.26092 ◽

2019 ◽

Vol 15 (2) ◽

pp. 128

Author(s):

Edison Ayakeding ◽

Keppi Sukesi ◽

Yayuk Yuliati

Keyword(s):

Linear Regression Analysis ◽

Multiple Linear Regression Analysis ◽

Individual Characteristics ◽

Influential Factors ◽

Community Empowerment ◽

Program Testing ◽

Food Research ◽

Food And Nutrition ◽

Observation Method ◽

The Individual

Papua is one of the provinces in Indonesia which has the characteristics of a different man in the business of fulfilling the needs of the family. The program of the Ministry of agriculture through community empowerment efforts to optimize the benefits of the grounds as a source of food family. Jayapura Regency is one of the areas that are also experiencing food security problems. Adequacy of food and nutrition is one of the most influential factors in producing quality human resources. The purpose of this research is to analyze the perceptions and the factors that influence the perception of farmers against the program Area Homes Preserved Food. Research conducted in the Western County of Sentani Dosai district of Jayapura of Papua by engaging 25 respondents who implement programs KRPL in 2013. The technique of collecting data through observation method, Now as well as granting interviews specifically. Type a descriptive quantitative data. The measurement of perception of farmers using likert scale gauge. The results of the measurements indicate that the level of perception of farmers against very low KRPL program. Testing free variables using multiple linear regression analysis. The results of the analysis showed that the fulfillment of the needs and knowledge of the real effect, While the individual characteristics, experience factor farmer KRPL and support agencies have no effect on real. The value of R-sq (adj) indicates the magnitude of the influence of variables against the perception that is free of 46.83%, While the 53.17% influenced by other factors outside of this research.Abstrak: Papua merupakan salah satu provinsi di Indonesia yang memiliki karakteristik manusia yang berbeda-beda dalam usaha pemenuhan kebutuhan keluarga. Program Kementerian Pertanian melalui upaya pemberdayaan masyarakat untuk mengoptimalkan manfaat pekarangan sebagai sumber pangan keluarga. Kabupaten Jayapura merupakan salah satu daerah yang juga mengalami masalah ketahanan pangan. Kecukupan pangan dan gizi merupakan salah satu faktor yang berpengaruh dalam menghasilkan sumber daya manusia yang berkualitas. Tujuan penelitian ini adalah menganalisis persepsi dan faktor-faktor yang mempengaruhi persepsi petani terhadap program Kawasan Rumah Pangan Lestari. Penelitian dilakukan di Kampung Dosai Distrik Sentani Barat Kabupaten Jayapura Papua dengan melibatkan 25 responden yang melaksanakan program KRPL pada tahun 2013. Teknik Pengumpulan data melalui metode observasi, pemberian angket serta wawancara secara spesifik. Jenis data deskriptif kuantitatif. Pengukuran persepsi petani menggunakan alat ukur skala likert. Hasil pengukuran menunjukkan bahwa tingkat persepsi petani terhadap program KRPL sangat rendah. Pengujian variabel bebas menggunakan alat analisis regresi linier berganda. Hasil analisis menunjukkan bahwa faktor pemenuhan kebutuhan dan pengetahuan berpengaruh nyata sedangkan faktor karakteristik individu, pengalaman usaha tani KRPL dan dukungan instansi tidak berpengaruh nyata. Nilai R-sq(adj) menunjukan besarnya pengaruh variabel bebas terhadap persepsi yaitu sebesar 46,83%, sedangakan 53,17% dipengaruhi faktor-faktor lain diluar dari pada penelitian ini.

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Negative gravitropism of Ginkgo biloba: growth stress and reaction wood formation

Holzforschung ◽

10.1515/hf-2015-0005 ◽

2016 ◽

Vol 70 (3) ◽

pp. 267-274 ◽

Cited By ~ 6

Author(s):

Tatsuya Shirai ◽

Hiroyuki Yamamoto ◽

Miyuki Matsuo ◽

Mikuri Inatsugu ◽

Masato Yoshida ◽

...

Keyword(s):

Ginkgo Biloba ◽

Lignin Content ◽

Linear Regression Analysis ◽

Multiple Linear Regression Analysis ◽

Wood Formation ◽

Growth Stress ◽

Reaction Wood ◽

Cellulose Content ◽

S2 Layer ◽

Negative Gravitropism

Abstract Ginkgo (Ginkgo biloba L.) forms thick, lignified secondary xylem in the cylindrical stem as in Pinales (commonly called conifers), although it has more phylogenetic affinity to Cycadales than to conifers. Ginkgo forms compression wood-like (CW-like) reaction wood (RW) in its inclined stem as it is the case in conifers. However, the distribution of growth stress is not yet investigated in the RW of ginkgo, and thus this tissue resulting from negative gravitropism is still waiting for closer consideration. The present study intended to fill this gap. It has been demonstrated that, indeed, ginkgo forms RW tissue on the lower side of the inclined stem, where the compressive growth stress (CGS) was generated. In the RW, the micorofibril angle in the S2 layer, the air-dried density, and the lignin content increased, whereas the cellulose content decreased. These data are quite similar to those of conifer CWs. The multiple linear regression analysis revealed that the CGS is significantly correlated by the changes in the aforementioned parameters. It can be safely concluded that the negative gravitropism of ginkgo is very similar to that of conifers.

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Microfibril Angle: Measurement, Variation and Relationships – A Review

IAWA Journal ◽

10.1163/22941932-90000192 ◽

2008 ◽

Vol 29 (4) ◽

pp. 345-386 ◽

Cited By ~ 154

Author(s):

Lloyd Donaldson

Keyword(s):

Cell Wall ◽

Large Scale ◽

Juvenile Wood ◽

Microfibril Angle ◽

Basic Density ◽

Angle Measurement ◽

Axial Stiffness ◽

Timber Species ◽

Increment Core ◽

X Ray

Microfibril angle (MFA) is perhaps the easiest ultrastructural variable to measure for wood cell walls, and certainly the only such variable that has been measured on a large scale. Because cellulose is crystalline, the MFA of the S2 layer can be measured by X-ray diffraction. Automated X-ray scanning devices such as SilviScan have produced large datasets for a range of timber species using increment core samples. In conifers, microfibril angles are large in the juvenile wood and small in the mature wood. MFA is larger at the base of the tree for a given ring number from the pith, and decreases with height, increasing slightly at the top tree. In hardwoods, similar patterns occur, but with much less variation and much smaller microfibril angles in juvenile wood. MFA has significant heritability, but is also influenced by environmental factors as shown by its increased values in compression wood, decreased values in tension wood and, often, increased values following nutrient or water supplementation. Adjacent individual tracheids can show moderate differences in MFA that may be related to tracheid length, but not to lumen diameter or cell wall thickness. While there has been strong interest in the MFA of the S2 layer, which dominates the axial stiffness properties of tracheids and fibres, there has been little attention given to the microfibril angles of S1 and S3 layers, which may influence collapse resistance and other lateral properties. Such investigations have been limited by the much greater difficulty of measuring angles for these wall layers. MFA, in combination with basic density, shows a strong relationship to longitudinal modulus of elasticity, and to longitudinal shrinkage, which are the main reasons for interest in this cell wall property in conifers. In hardwoods, MFA is of more interest in relation to growth stress and shrinkage behaviour.

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Molecular xylem cell wall structure of an inclined Cycas micronesica stem, a tropical gymnosperm

IAWA Journal ◽

10.1163/22941932-90000001 ◽

2010 ◽

Vol 31 (1) ◽

pp. 3-11 ◽

Cited By ~ 6

Author(s):

Clemens M. Altaner ◽

Michael C. Jarvis ◽

Jack B. Fisher ◽

Thomas E. Marler

Keyword(s):

Cell Wall ◽

Compression Wood ◽

Lignin Content ◽

Microfibril Angle ◽

Picea Sitchensis ◽

Wall Structure ◽

Crystalline Cellulose ◽

Cellulose Structure ◽

Molecular Features ◽

Cellulose Fibrils

The molecular structure of tracheid walls of an inclined eccentrically grown stem of Cycas micronesica K.D. Hill did not differ between the upper and lower side. The absence the typical molecular features of compression wood tracheids, i.e. an increased galactose and lignin content as well as an increased microfibril angle, indicated that cycads do not have the ability to form even very mild forms of compression wood, which lacks anatomical features commonly observed in compression wood. Analysis of the sugar monomers in Cycas micronesica tracheids did reveal a rather unique composition of the non-cellulosic polysaccharides for a gymnosperm. The low mannose and high xylose content resembled a cell wall matrix common in angiosperms. The crystalline cellulose structure in Cycas micronesica tracheids closely resembled those of secondary cell walls in Picea sitchensis (Bong.) Carr. tracheids. However, the spacing between the sheets of cellulose chains was wider and the cellulose fibrils appeared to form larger aggregates than in Sitka spruce tracheids.

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Comparing Mechanical Properties of Normal and Compression Wood in Norway Spruce: The Role of Lignin in Compression Parallel to the Grain

Holzforschung ◽

10.1515/hf.2002.062 ◽

2002 ◽

Vol 56 (4) ◽

pp. 395-401 ◽

Cited By ~ 26

Author(s):

W. Gindl

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Cell Wall ◽

Mechanical Testing ◽

Cell Walls ◽

Compression Wood ◽

Lignin Content ◽

Microfibril Angle ◽

Compression Failure

Summary Cell-wall lignin content and composition, as well as microfibril angle of normal and compression wood samples were determined prior to mechanical testing in compression parallel to the grain. No effect of increased lignin content on the Young's modulus in compression wood was discernible because of the dominating influence of microfibril angle. In contrast, compressive strength of compression wood was not negatively affected by the high microfibril angle. It is proposed that the observed high lignification in compression wood increases the resistance of the cell walls to compression failure. An increased percentage of p-hydroxyphenylpropane units observed in compression wood lignin may also contribute to the comparably high compressive strength of compression wood.

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Infrared photo-induced force microscopy unveils nanoscale features of Norway spruce fibre wall

Cellulose ◽

10.1007/s10570-021-04006-2 ◽

2021 ◽

Author(s):

Kavindra Kumar Kesari ◽

Padraic O’Reilly ◽

Jani Seitsonen ◽

Janne Ruokolainen ◽

Tapani Vuorinen

Keyword(s):

Cell Wall ◽

Chemical Composition ◽

Norway Spruce ◽

Spatial Resolution ◽

Lignin Content ◽

Force Microscopy ◽

Transmission Electron ◽

High Resolution Images ◽

The Individual ◽

20 Nm

AbstractInfrared photo-induced force microscopy (IR PiFM) was applied for imaging ultrathin sections of Norway spruce (Picea abies) at 800–1885 cm−1 with varying scanning steps from 0.6 to 30 nm. Cell wall sublayers were visualized in the low-resolution mode based on differences in their chemical composition. The spectra from the individual sublayers demonstrated differences in the orientation of cellulose elementary fibrils (EFs) and in the content and structure of lignin. The high-resolution images revealed 5–20 nm wide lignin-free areas in the S1 layer. Full spectra collected from a non-lignified spot and at a short distance apart from it verified an abrupt change in the lignin content and the presence of tangentially oriented EFs. Line scans across the lignin-free areas corresponded to a spatial resolution of ≤ 5 nm. The ability of IR PiFM to resolve structures based on their chemical composition differentiates it from transmission electron microscopy that can reach a similar spatial resolution in imaging ultrathin wood sections. In comparison with Raman imaging, IR PiFM can acquire chemical images with ≥ 50 times higher spatial resolution. IR PiFM is also a surface-sensitive technique that is important for reaching the high spatial resolution in anisotropic samples like the cell wall. All these features make IR PiFM a highly promising technique for analyzing the recalcitrant nature of lignocellulosic biomass for its conversion into various materials and chemicals. Graphic abstract

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The effect of audit opinions, implementation of audit recommendations, and findings of state losses on corruption levels in the ministries and institutions of the Republic of Indonesia

Jurnal Tata Kelola & Akuntabilitas Keuangan Negara ◽

10.28986/jtaken.v7i1.471 ◽

2021 ◽

Vol 7 (1) ◽

pp. 113-129

Author(s):

Muhamad Agung Budiman ◽

Firdaus Amyar

Keyword(s):

Linear Regression Analysis ◽

National Development ◽

Secondary Data ◽

Multiple Linear Regression Analysis ◽

Public Confidence ◽

Financial Reports ◽

Audit Opinions ◽

The Republic ◽

The Individual ◽

Combined Impact

The prevalence of corruption in Indonesia is increasing every year. This fact has further undermined public confidence to strengthen governance and is a critical barrier to national development. This study aims to empirically examine the individual and combined impact of audit opinions, the implementation of audit recommendations, and findings of state losses by the Indonesian Supreme Audit Board (BPK) on the prevalence of corruption in ministries and institutions in the Republic of Indonesia. Using multiple linear regression analysis, this study used a purposive sampling method and investigated 72 ministries using secondary data from 2014 to 2017 obtained from BPK and the Corruption Eradication Commission of the Republic of Indonesia (KPK). This study indicates that audit opinions and the implementation of audit recommendations do not affect corruption in Indonesian ministries and institutions. In contrast, findings of state losses do have an influence. The combination of audit opinions, implementation of audit recommendations, and findings of simultaneous state losses do not affect corruption cases in Indonesian ministries and institutions. BPK can use the results of this study to formulate approaches and recommendations for auditing government financial reports that have a strong correlation with corruption eradication. Moreover, KPK needs to be more vigorous in its efforts to eradicate corruption, including establishing closer cooperation with BPK because the results of this research show that findings of state losses by BPK are closely related to corruption cases.

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Turn Fast and Win: The Importance of Acyclic Phases in Top-Elite Female Swimmers

Sports ◽

10.3390/sports9090122 ◽

2021 ◽

Vol 9 (9) ◽

pp. 122

Author(s):

Dennis-Peter Born ◽

Joris Kuger ◽

Marek Polach ◽

Michael Romann

Keyword(s):

Regression Analysis ◽

Linear Regression ◽

Multiple Linear Regression ◽

Linear Regression Analysis ◽

Multiple Linear Regression Analysis ◽

Race Time ◽

Short Course ◽

Mechanistic Analysis ◽

The Individual ◽

Event Based

The aim of the study was to investigate the effect of start and turn performances on race times in top-elite female swimmers and provide benchmarks for all performance levels, all swimming strokes, and all race distances of the European Short-Course Championships (EC). The individual races (n = 798) of all female competitors (age: 20.6 ± 3.9 years, FINA points: 792 ± 78) were video-monitored for subsequent analysis of start and turn performances. Benchmarks were established across all competitors of each event based on the 10th, 25th, 50th, 75th, and 90th percentiles. Start and turn performances contributed up to 27.43% and 56.37% to total race time, respectively. Mechanistic analysis revealed that the fastest swimmers had the lowest contribution of the acyclic phases to race time. Therefore, relative to their faster race times, these swimmers were even faster during starts and turns. Multiple linear regression analysis showed large effects of turn performance on 50, 100, 200, 400, and 800 m race times (β = 0.616, 0.813, 0.988, 1.004, and 1.011, respectively), while the effect of start performance continuously decreased the longer the race distance. As turn performance may be the distinguishing factor in modern short-course races, benchmarks should be used to set goals and establish training guidelines depending on the targeted race time.

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Economic value analysis of Simarjarunjung Nature Tourism Area, Simalungun Regency, North Sumatera

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/912/1/012050 ◽

2021 ◽

Vol 912 (1) ◽

pp. 012050

Author(s):

A Purwoko ◽

S Latifah ◽

C Siahaan

Keyword(s):

Linear Regression Analysis ◽

Economic Value ◽

Multiple Linear Regression Analysis ◽

Travel Cost ◽

Travel Cost Method ◽

Economic Potential ◽

Value Analysis ◽

Nature Tourism ◽

Tourism Potential ◽

The Individual

Abstract Indonesia’s natural potential is very diverse, one of which is the natural tourism potential of the provinces in Indonesia. Sumatra, especially North Sumatra, is currently developing its natural potential, namely the Simarjarunjung Nature Tourism Area. This area is a magnet for tourists, because the hill is one of the ideal locations to see the landscape of Lake Toba. This study is aimed to analyze the total economic value with the travel method (Travel Cost Method) and the factors that influence tourists’ visits to the Simarjarunjung Natural Tourism Area. The method used to estimate the economic potential of tourism activities in the Simarjarunjung Nature Tourism Area is the individual travel cost method, while to determine the factors that affect the intensity of tourist visits to the Simarjarunjung Nature Tourism Area, it is determined by multiple linear regression analysis. The research data were obtained by asking questions on the questionnaire to the visitors. The results showed that the economic potential of the Simarjarunjung Nature Tourism Area reached IDR. 6,207,894,000/year, and the variables that had a significant effect on the intensity of tourists’ visits to the Simarjarunjung Nature Tourism Area were travel costs, age, and distance variables.

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