Australian Journal of Basic and Applied Sciences
         [ Home ] [ Instructions ] [ Contact us ]

May 2018


Cavitation and embolism in plants: literature review

Thayllane de Campos Siega, Edson Bertoldo, Lilian de Souza Vismara, Cleiton Nicareta, Américo Wagner Junior

Abstract Background: The appearance and formation of air bubbles in xylem conducting vessels can drastically reduce the hydraulic capacity of the plants, since this problem is pointed out as one of the main mechanisms that cause the mortality of the woody plants, mainly due to the water deficit and, in smaller degree, due to the freezing-thawing events of the water, during the cold. Plants have mechanisms to minimize the effects of cavitation and embolism, but these vary between plants and even within the same species. Objective: In order to better understand the "cavitation and embolism" theme, this research was carried out based on a literature review, in which the articles of higher quality and relevance regarding the theme were selected.

[ FULL TEXT PDF 1-4 ] DOI: 10.22587/ajbas.2018.12.5.1


Potential of phosphite products in the control of Sclerotinia sclerotiorum in vitro

Stheffani Lucca, Joanilson Vieira Prestes Junior, Thayllane de Campos Siega, Fabíola Mundstock, Sérgio Miguel Mazaro

Abstract Background: The pathogen Sclerotinia sclerotiorum is a soil fungus that causes serious damage to several crops of economic interest. Objective: The objective of this study was to evaluate the potential of phosphite products in the control of Sclerotinia sclerotiorum under in vitro conditions. The experiment was carried out in the Phytosanitary laboratory of the Universidade Tecnológica Federal do Paraná, Dois Vizinhos campus. The products used in the experiment were potassium phosphite, manganese phosphite and copper phosphite. The experimental design was completely randomized with four replicates, an experimental unit consisting of a Petri® plate. The mycelial growth assays were at 12, 24, 48, 72 and 96 hours after incubation of the plates in BOD, and the evaluations were stopped as soon as the control plate reached full growth. Results: The results showed that both products had potential to inhibit mycelial growth of the pathogen S. sclerotiorum and at the dose of 60 μL there was complete inhibition of fungus growth. Conclusion: At the end of the study, we concluded that there is potential of phosphite based products in the control of S. sclerotiorum in vitro. However future work should consider the pipeline(pathosystem) of interest, and field trials on the desired crops, to demonstrate the behavior of the plants in relation to the products.

[ FULL TEXT PDF 5-7 ] DOI: 10.22587/ajbas.2018.12.5.2


Identification of Grip Profile for Hand Tool – A Preliminary Ergonomics Study

Mohd H Ibrahim, Nor A Said, Ummi N Roslan and Aaina N Mohd A.

Abstract The use of tools is still widely valued in industries at various levels. The range of hand tools application varies from a simple task of filing tool to a complicated, complex and precision-demanding tasks such as that of surgical scalpels. Hence, it becomes highly essential to design the tool for ‘comfort’ from the perspective of user. The aim of this study is to perform a preliminary study of hand grip profile. Plastesine was used in order to mould hand profile prior to systematically dimensioning into CAD. Preliminary sample of 5 males and females were considered. It was noted that male grip profiles are larger than female grip profile. However, female grip profiles tend to show more variation. Further works is recommended by takings more samples that could provide more accurate statistical analysis in designing future hands tool.

[ FULL TEXT PDF 8-11 ] DOI: 10.22587/ajbas.2018.12.5.3


The Impact of Resettlement on Livelihood of the Bajo Tribe Community (A Case in Tomini Bay, Indonesia)

Muhammad Obie

Abstract The resettlement to remote communities became the new order governmental instrument to control the economic and political stability. It was designed in such a way as to exclude locally long-lasting communities fostering social, cultural, and economic integration with their natural environment, had created instability and loss of economic assets for the local communities. This research was to analyze the impact of resettlement on livelihood of the Bajo tribe community in Tomini bay. This research used the critical theory paradigm, qualitative approach, and ethnographic method. The data collection was done through indepth interview, an observation, and library research. The result of research stated that the Bajo tribe community was originally united to live on the sea surface, faced the reality of split life, along with the weakening of social capital. Similarly, indigenous institution is shaken because some of the custom figures follow the resettlement program. The Bajo tribe who followed the resettlement program lost the natural capital, sea-based livelihood after their difficult accessed to coastal and marine resources. The removal of the Bajo tribe in the resettlement program forced them to abandon their hereditary roots that were built up from generation to generation along with the coastal and marine environments. As a result, access of the Bajo tribe on coastal and marine resources eventually disrupted and even abandoned altogether. The Bajo tribe should lose its hereditary livelihood bases on coastal and marine outcomes. Meanwhile, in the depressed life on land, the Bajo tribe was forced to undergo a livelihood bases that was not its cultural roots. They are even forced to farm in unlikely smallholdings since the government-provided land for every family head is not sufficient even to produce family food. As the result they had to accept the reality of life in the shackles of poverty. They are difficult in fulfilling their daily needs since the government forces them to pursue lives that are historically not theirs. Finally, this research concluded that the resettlement program as implemented under pressure and coercion has a negative impact on the Bajo tribe community. The Bajo tribe who hereditary livelihood hangs on coastal and marine resources, the coercion of resettlement program has deprived the cultural roots of Bajo tribe attached to the coast and sea.

[ FULL TEXT PDF 12-16 ] DOI: 10.22587/ajbas.2018.12.5.4


Dye-Sensitized Solar Cell Using Natural Vegetable Dyes Based On Anatase Phase

Hesham Ibrahim Saleh

Abstract: Background: The performance of dye sensitized solar cells (DSSCs) is mainly based on the dye as a sensitizer. The use of natural dyes extracted from vegetables as sensitizers for the conversion of solar energy into electricity is very interesting because it improves the economical aspect and makes important profit from the environmental. Objective: The objective of the present study was to prepare a natural dye (extracted from purple cabbage, purple carrots and a mixture of them) available easily, low cost, easy to prepare, non-toxic and friendly to the environment for use as a sensitizer in the solar cell. Also we attempt to take advantage of the proposed synthetic route of anatase-TiO2- nanoparticles phase in a simple way so as to prepare photo anodes for the fabrication of the cell. Thus DSSCs device were fabricated using TiO2 nanoparticles for the three sensitizers and their photovoltaic performance were determined Results: The IR spectra of using natural extracts contain bands that can be assigned to the coloring components found in the dye of anthocyanin compound. Microscope (SEM) and X-Ray Diffractometer (XRD) were used to characterize the morphology and structure of the TiO2. The dyes have shown absorption in broad range of the visible region (524–561 nm) of the solar spectrum and appreciable adsorption on to the semiconductor (a-TiO2) surface. The DSSCs made using the extracted dyes have shown that the open circuit voltages (Voc) varied from 0.585 to 0.66 V, short circuit photocurrent densities (Jsc) ranged from 1.96 to 3.16 mA cm−2 and energy conversion efficiency (η%) ranged from 0.538 to 1.29. Conclusions: anatase-TiO2 nano-crystalline powder was successfully synthesized by using the chemical hydrolysis technique with some modifications. By controlling the conditions properly, nano-TiO2 powders of anatase form with the grain size of 44 nm could be obtained. Natural dyes prepared from the vegetables, purple cabbage and purple carrots were successfully extracted by using ethanol acidified with 0.01% acetic acid (as solvent). The highest conversion efficiency was obtained for the DSSC fabricated using a mixture from purple cabbage and purple

[ FULL TEXT PDF 17-23 ] DOI: 10.22587/ajbas.2018.12.5.5


The anatomic response of Urochloa P. Beauv. cultivars to different sources of nitrogen fertilization

Odair de Souza Fagundes, Norberto Gomes Ribeiro Júnior, Antonio Carlos Silveiro Silva, Soraia Olivastro Teixeira, Oscar Mitsuo Yamashita, Ivone Vieira da Silva

Abstract Background: Nitrogen is an essential element widely used as fertilizer to enable the development of tropical forage species. However, high doses of nitrogen fertilizers may change plant anatomy and reduce the digestibility of forage. Objective: The aim of the current study is to assess possible changes in the proportion of leaf tissues in two forage species - Urochloa brizantha cv. Marandu and Urochloa hibrida cv. Mulato II - subjected to nitrogen fertilization. Results: The herein applied treatments and doses did not lead to histological differences in plant tissues or in plant tissue proportions. They remained proportional to the fibrous fractions of the analyzed material. Similar to the histological behavior, nitrogen substrates did not lead to sharp group differentiation based on the herein analyzed variables. Fertilization with urea led to significant increase in the fibrous proportions and only had significant influence on midrib. This fertilization type showed more relevant results in the Mulato II cultivar, which was subjected to the application of 100 kg ha-1 of urea. Fertilization with ammonium sulfate was the source presenting less influence on crude fiber proportions; it did not influence forage digestibility. Conclusion: The treatments with nitrogen fertilizers evaluated generate few changes in the proportion of leaf tissue in the tested cultivars. The dose of 150 kg ha-1 of ammonium sulfate (AS) causes the lowest changes in the ratio of crude fibers, which indicates the best cost-benefit for the production of animal feed and animal production. Future studies with in vitro digestibility tests for these cultivars are necessary to confirm the maintenance or alteration of the characteristics of these fibers.

[ FULL TEXT PDF 24-30 ] DOI: 10.22587/ajbas.2018.12.5.6


BER Vs Eb/N0 BPSK Modulation over Different Types of Channel

Mustafa Maad Hamdi and Mohammed Jabbar Mohammed

Abstract This paper derives a brief comparison using MATLAB simulation between the response of BPSK over different type of channels. The first one is when the transmitting signal affected by AWGN channel, the second one is when the channel is Rayleigh flat fading, and the last one is when the BPSK simulated over Rician fading channel. This simulation is used to determine the bit error rate (BER) which is the number of bit errors divided by the total number of transmitted bits over a channel. The result shows a good agreement between the simulated and theoretical plots for BPSK modulation that there is no difference between the BER performance of BPSK over Additive White Gaussian Noise (AWGN) channel and the theoretical Energy per Bit to Noise Power (Eb/No) this is due to the 180o phase shift between the two bits (symbols). The result also shows that the BER response with Eb/No over Rayleigh channel is also the same but with slow response compared with AWGN. With AWGN, the BER performance reaches 10-02 at 4dB, but with Rayleigh it takes 13dB to reach the same value. That is there is 9dB difference as an example for the BER to reach 10-02.

[ FULL TEXT PDF 31-38 ] DOI: 10.22587/ajbas.2018.12.5.7


Economic viability of different management regimes for Eucalyptus grandis W. Hillstands

Gabriel Paes Marangon, Paulo Renato Schneider, Emanuel Arnoni Costa, Terezinha Bezerra Albino Oliveira, Jorge Antônio de Farias, César Augusto Guimarães Finger

Abstract Background:The economic viability of different management regimes of forest stands is one of the most adequate alternatives to assess the risk of investments in forestation. Objective:We evaluate the ideal management regime for consolidated commercial stands of Eucalyptus grandislocalized in Rio Grande do Sul, Brazil.Methods:The measured forest stands are located in the Central-Western regionof Rio Grande do Sul and the Metropolitan region of Porto Alegre. The economic viability has been considered according to the Internal Rate of Return (IRR), Net Present Value (NPV), Annualized Net Present Value (ANPV), Benefit-Cost Ratio (BCR), and Profitability Index (PI) criteria. Three management regimes were simulated: I) trees with no thinning and clear-cutting at 52.8 months; II) trees with one thinning at 53.0 months and clear-cutting at 85.0 months; and III) trees with two thinnings (52.8 and 85.4 months) and clear-cutting at 121.8 months.Results:Investments in reforestation with Eucalyptus grandis under different management regimes provided economic returns, with emphasis to regime III, which was the most attractive.Conclusion:By according with the viability results that consider the variation of capital value along the management regimes, it was possible to identify the ideal occupation of the site, with control of production and competition levels in line with the maximization of economic profitability.

[ FULL TEXT PDF 39-46 ] DOI: 10.22587/ajbas.2018.12.5.8


International Migrant Labors in Tourism and Hospitality: Developing a Framework of Motivational Pull Factors

Nurhazani Mohd. Shariff, Azlan Zainol Abidin, Nur Syafiqah Abd. Ghani, Titing Kartika

Abstract Background: International migrant labors play essential roles in the service industry particularly for tourism and hospitality. Their arrivals in the industry have contributed to the gap of fulfilling employment issues. Most sectors within the industry for instance restaurant, accommodation and transportation are recruiting the international migrant labors to fulfill several positions including the unskilled, semi-skilled and professionals. Objective: There is lack of study on international migrant labors in the tourism and hospitality industry particularly relating to motivational factors. Hence, the main objective of the paper is to identify the pull factors which motivate international migrant labors to work in the tourism and hospitality industry. The study involved exploratory research where significant literature on pull factors motivating the international migrant labors to work within the industry were reviewed. Results: Based from previous studies, the framework highlights several factors namely high wages, better employment, better facilities, opportunity for career growth and job security as five major pull factors motivating the international migrant labors to work in the tourism and hospitality industry. Conclusion: The framework is considered as an advance contribution to the industry in terms of understanding the most vital motivational factors which pull the international migrant labors to work in the industry. These identified factors would also contribute to further research in determining whether they significantly motivate the international migrant labors to work in the industry. Further, taking these factors into account would assist the human resource managers in the industry to plan for effective positions to be fulfilled by the international migrant labors.

[ FULL TEXT PDF 47-51 ] DOI: 10.22587/ajbas.2018.12.5.9


Germination potential of Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz var. ferrea) seeds in contact with petroleum hydrocarbons

Danielle Marie Macedo Sousa, Elis Regina Costa de Morais, Celsemy Eleutério Maia, Maria Valdete da Costa

Abstract Background: Libidibia ferrea belongs to the Fabaceae family, an early secondary species known as jucá, its propagation occurs mainly through the seeds. Several vital functions of the plants are affected by the pollutants and due to these, visible damages can occur, depending on the influence of both the environment and the characteristics of the species itself, oil is one of the pollutants that has been causing impacts to nature, mainly in areas destined to the planting of tree seeds, affecting the germination and emergence of these species. Objetive: The objective of this study was to evaluate the germination of L. ferrea seeds over time when subjected to contact with petroleum, based on the following treatments: witness (intact seed), intact and scarified seeds, submerged in oil for 1 h and 24 hours.It is important to emphasize that there are no previous experimental studies on the germination of Caatinga tree species submitted to contamination by petroleum hydrocarbons, and the species presenting good results in this investigation could be used for phytoremediation studies and possibly be a alternative in the use in productive soils contaminated by petroleum, which are generally characterized by having a low productivity. Results: The submerged oil seeds, followed or not by scarification, showed differences in the germination curves and the germinative behavior over time. The maximum germination (Gmax)estimated for the witness was 69%, followed by the intact seeds in contact with oil for 1 h of 54% and 24 h of 66%, whereas for seeds physically scarified, the Gmax estimated was lower for exposure times of 1 h (47%) and 24 h (47%). Conclusions: There were differences in germination of the seeds over time between the evaluated treatments, with each treatment having a faster initial growth phase, followed by stabilization. Scarified seeds at both oil contact times showed slower germination over time, but at the end of the process the values were higher when compared to mechanically scarified seeds.

[ FULL TEXT PDF 52-56 ] DOI: 10.22587/ajbas.2018.12.5.10


Geometric Correction of High Resolution Satellite Imagery Using Hybrid Non-parametric Model

Ahmed Habib, Zainab Weshahy, Mohamed El-Ghazaly, Ayman El-Shehaby.

Abstract: Updating geographic information using high resolution satellite images has become a major competitor to the traditional photogrammetric works. This research presents a new technique to achieve geometric correction, starting with automatic satellite imagery matching with digital photogrammetric data, after outliers' exclusion. Matched points are ortho-corrected using DDTM. A downward Multi-layer perceptron neural networks technique will be used in the process of network training, instead of using the classic upward technique. In the new training process image coordinates were used as inputs and their corresponding ground coordinates were used as outputs. The trained network was used in predicting ground coordinates of a set of new regularized image points in the same space domain of the matched point dataset. Rational function model (RFM) will be implemented using regularized ortho-corrected points as GCPs in order to reach the final relationship parameters between satellite imagery and the 3D object coordinates. The new technique led to an improvement of the accuracy by damping down the error to 0.67 the error resulting from the conventional RFM model.

[ FULL TEXT PDF 57-61 ] DOI: 10.22587/ajbas.2018.12.5.11