PR-10 is a member of pathogenesis-related (PR) genes elicited by the plant’s defense mechanism during pathogen attack.
Elevated expression of PR-10 upon different pathogen invasions has been observed in many plant species suggesting
its role as an anti-bacterial, anti-viral and anti-fungal gene. However, the effect of PR-10 in mitigating the infection of
Fusarium oxysporum f. sp. cubense (Foc), the causal agent of Fusarium wilt in banana has not been reported. In this
study, the coding sequences of PR-10 gene isolated from Foc resistant Musa acuminata ssp. malaccensis (MaPR-10)
were integrated into a local Foc susceptible commercial banana cultivar, Berangan via co-cultivation of embryogenic
cell suspension and Agrobacterium tumefaciens. Out of 17 putative transgenic lines established, 11 of them positively
harbored MaPR-10. Among these, Line-19 plantlets showed the most rapid in-vitro propagation and successfully overexpressed the transgene. Following a nursery challenge experiment with a virulent Foc race 4 (CI HIR) isolate, about 30%
of Line-19 plants showed a one-week delay in disease progression when compared to the untransformed controls. From
the final evaluation performed in the 5th week-post-inoculation, the leaf symptoms index (LSI) and rhizome discoloration
index (RDI) of Line-19 was 3.4 and 6.1, respectively, indicating the disease had progressed. The findings of this study
enrich the current existing knowledge on the roles of PR-10 in combating fungal disease in plants.
X-ray computed tomography (XCT) became an important instrument for quality assurance in industry products as a
non-destructive testing tool for inspection, evaluation, analysis and dimensional metrology. Thus, a high-quality image
is required. Due to the polychromatic nature of X-ray energy in XCT, this leads to errors in attenuation coefficient
which is generally known as beam hardening artifact. This leads to a distortion or blurring-like cupping and streak in
the reconstruction images, where a significant decrease in imaging quality is observed. In this paper, recent research
publications regarding common practical correction methods that were adopted to improve an imaging quality have been
discussed. It was observed from the discussion and evaluation, that a problem behind beam hardening reduction for the
multi-materials object, especially in the absence of prior information about X-ray spectrum and material characterizations
would be a significant research contribution, if the correction could be achieved without the need to perform forward
projections and multiple reconstructions.
In order to understand the characteristics of acoustic wave propagation in rocks within seismic frequency band (<100
Hz), the velocities of longitudinal and transverse waves of four different types of rocks were tested using low-frequency
stress-strain method by means of the physical testing system of rock at low frequency and the experimental data of acoustic
velocities of four different types of rocks at this frequency band were obtained. The experimental results showed that the
acoustic velocities of four different types of rocks increased with the increase of temperature and pressure within the
temperature and pressure ranges set by the experiment. The acoustic velocity of fine sandstone at 50% water saturation
was smaller than that of dry sample. The acoustic velocities of four different types of rocks were different and the velocities
of longitudinal waves of gritstone, fine sandstone, argillaceous siltstone and mudstone increased in turn under similar
conditions and were smaller than those at ultrasonic frequency. Few of existing studies focus on the acoustic velocity at
seismic frequency band, thus, further understanding of the acoustic characteristics at this seismic frequency band still
requires more experimental data.
It is well-known that the characteristics of hardness and drillability are influenced by microstructure of rock. In this study, rock properties were analyzed on grain size and grain content. Coarse-grain and fine-grain sandstones were tested under successive indentation condition. Eighteen groups of sandstone and shale were employed for the drillability test. Indentation tests results showed that grain size influenced the low point of residual hardness, the crushing depth and volume and grain content influenced the peak point of hardness. The drillability values of shale increased with increasing contents of clay and quartz. Meanwhile, drillability values of sandstone increased with increasing content of quartz, but decreased with increasing content of clay. Therefore, these preliminary studies show great potential applications for selecting suitable bit type and formulating drilling program as a function of rock microstructure and crushing rock method for bit in the oil drilling.
Based on the hydraulic fracture width gradually narrows along the fracture length, with consideration of the mutual influences of fracture, non-uniform inflow of fractures segments and variable mass flow in the fracture comprehensively, a spatial separation method and time separation method were used to establish fracture horizontal well’s dynamic coupling model of reservoir seepage and fracture flow. The results showed that the calculation productivity of variable width model is higher than that of the fixed width model, while the difference becomes smaller as time increase. Due to mutual interference of the fractures, the production of outer fracture is higher than that of the inner fracture. When the dimensionless fracture conductivity is 0.1, the middle segment of the fracture dominates the productivity and local peak emerges near the horizontal well. The flow in the fracture is with the ‘double U’ type distribution. As the dimensionless fracture conductivity increase, the fractures productivity mainly through the tips and the flow in the fractures with the ‘U’ type distribution. Using the established fracture width variable productivity prediction model, one can achieve the quantitative optimization of fracture shape.
Following rapid technological and industrial development, factories have been equipped with a great deal of machines.
The blend of industrial and residential areas in turn resulted in many environmental problems. In particular, machine
operation causes noise pollution that easily causes physiological and psychological discomfort for the human body thus
makes noise abatement a crucial and urgent issue. In this study, vermiculite functional fillers were added to polyurethane
(PU) foam mixtures in order to form sound absorbent PU foams. The correlations between the contents of functional fillers
and the sound absorption of flexible and rigid PU foams were then examined. The optimal PU foams were combined with
PET/carbon fiber matrices in order to yield the electromagnetic shielding effectiveness. The sound absorption, noise
reduction coefficient (NRC), electromagnetic shielding effectiveness and resilience rate of the composite boards were
finally evaluated. The test results indicated that rigid PU foam composites can reach a sound absorption coefficient of
0.8 while the flexible PU foam composites have higher mechanical properties.
The rock of gas tight reservoir is more heterogeneous than that of conventional sandstone reservoir and is more prone to water-blockage because of the invasion of operation fluid. This paper presented a new approach for the analysis of the capillary pressure curve for tight gas reservoir. Herein, the saturation equation with fractal dimension proved the previous observation that the log-log plot of capillary pressure against water saturation is a straight line, which is quite different from the popular observation by Corey’s correlation. How to transform the capillary pressure curve to relative permeability curve was also discussed with fractal dimension. The fractal dimension of capillary pressure, which is not only an indication of heterogeneity, can also reveal the potential water blocks in tight gas wells. If the rock has higher fractal dimension, being at the same water saturation, the capillary pressure will be higher and the relative permeability of water will be smaller, which means higher injection pressure is required to displace the trapped water in reservoir. It is suggested that for the tight gas pay zone with higher fractal dimension, more precautions should be taken to prevent the water trapping during drilling or stimulating operation.
A series of ester compounds derived from ricinoleic acid to be used as biolubricants base stock have been synthesized. The resulting products were confirmed by FTIR and NMR analyses. The synthesis was carried out in three stages: epoxidation of ricinoleic acid; synthesis of 10,12-dihydroxy-9-acyloxystearic acid from epoxidized ricinoleic acid with various fatty acids and esterification of the acyloxystearic acid products with octanol to yield octyl-10,12-dihydroxy-9-acyloxystearate. The viscosities, flash points and pour points (PP) behavior of the products were measured. The resulting esters had an increased in molar weight and viscosity and decreased in pour points as compared to ricinoleic acid.
Aloi Fe-Cr (Cr: 9-30 brt%) telah dikenakan pengoksidaan berkitar dalam Ar-20%O2, Ar-20%O2-5%H2O dan Ar-10%H2-5%H2O (tekanan separa oksigen, pO2 = 1.1 × 10-16atm), pada suhu 950oC. Pengukuran perubahan berat pengoksidaan menunjukkan secara umunnya bahawa peningkatan kandungan Cr dalam aloi akan mengurangkan kadar pengoksidaan. Untuk aloi Cr≤17%, ‘pengoksidaan pemecahan’ telah dapat diperhatikan. Untuk aloi Cr≥25%, penambahan berat adalah sangat rendah disebabkan oleh pembentukan lapisan Cr2O3. Penambahan 5%H2O kepada Ar-20%O2 dapat mempercepatkan lagi kadar pengoksidaan pada aloi yang mempunyai Cr≤20%. Walau bagaimanapun, kesan pencepatan ini tidak berlaku pada aloi yang mempunyai kandungan Cr yang tinggi. Analisis XRD menunjukkan aloi yang mempunyai kandungan Cr≤20%, wustit dan spinel terbentuk pada pO2 yang rendah, manakala pada pO2 yang tinggi, hematit, oksida besi dan spinel didapati terbentuk. Untuk aloi yang mempunyai kandungan Cr yang tinggi, hanya Cr2O3 dapat dikesan. Analisis keratan rentas menunjukkan bahawa spinel terbentuk melalui pengoksidaan dalaman. Ketebalan dan saiz zon oksida dalaman bertambah dengan bertambahnya kandungan Cr. Lapisan kromium oksida tunggal yang tumpat dapat diperhatikan apabila kandungan Cr melebihi 25%. Kerak oksida yang terbentuk di dalam wap air adalah lebih poros dan kurang padat berbanding kerak yang terbentuk dalam keadaan oksigen kering. Kesan wap air ke atas peningkatan pengoksidaan aloi Fe-Cr telah dibincangkan daripada aspek interaksi gas-pepejal.
It has not been well known how climate and habitat variables will influence the distribution of plant species to some extents at mesoscales. In this report, by using the distribution of aquatic plants in Western Ghats, a biodiversity hotspot in tropical Asian region, I quantify the relative importance of climate and habitat variables on structuring spatially species richness and taxonomic diversity patterns using structural equation modeling. All the sampling qudrats in the region used for the study has a spatial resolution of 0.5 latitude × 0.5 longitude. The results showed that species richness is high in both northern and southern part of the region, while low in the middle part. In contrast, taxonomic distinctiveness is relatively homogeneous over all the sampling quadrats in the region. Structural equation modeling suggested that taxonomic distinctiveness patterns of aquatic plants in the region follow temperature (partial regression coefficient=0.31, p<0.05) and elevational (partial regression coefficient=0.31, p<0.05) gradients, while richness patterns cannot be explained by any of the currently used variables. In conclusion, environmental variables that are related to taxonomic distinctiveness would not be related to richness, given the fact that these two quantities are orthogonal more or less. Both climate and habitat are equally influential on taxonomic distinctiveness patterns for aquatic plants in Western Ghats of India.
Proses pergerakan gigi semasa rawatan ortodontik boleh dikelaskan kepada empat fasa iaitu pengaktifan (berkait inflamasi terhadap tisu serta kematian sel), penyerapan, proses berbalik dan pembentukan tulang. Pergerakan gigi ini berkait rapat dengan perubahan metabolik di sekitar mulut. Objektif kajian ini adalah untuk menentukan profil penanda biologi enzim di dalam air liur individu yang menerima rawatan ortodontik iaitu laktat dehidrogenas (LDH) bagi proses inflamasi, asid fosfatase rintang tartarat (TRAP) bagi proses penyerapan tulang dan alkali fosfatase (ALP) bagi proses pembentukan tulang. Sampel air liur diambil daripada 6 individu yang menerima rawatan ortodontik. Aktiviti kesemua enzim diambil sebelum pendakap dipasang (aktiviti normal) diikuti dengan hari ke-3, 7, 10, 14, 17, 21, 24, 28 dan 31 selepas pengaktifan. Hasil kajian mendapati kesemua enzim (LDH, TRAP and ALP) menunjukkan peningkatan yang signifikan (p≤0.05) selepas rawatan diberikan berbanding aktiviti normal. LDH didapati meningkat pada peringkat awal rawatan (hari ke-3,7 dan 10), TRAP pada hari ke 14 dan 17 diikuti dengan ALP pada hari ke-17, 21 dan 24. Sebagai kesimpulan, profil enzim sepanjang rawatan ortodontik menunjukkan proses inflamasi berlaku di peringkat awal rawatan diikuti proses penyerapan dan pembentukan tulang. Selain itu, keseluruhan fasa inflamasi, penyerapan dan pembentukan tulang ortodontik didapati mengambil masa 24 hari.
Suar suria merujuk kepada aktiviti matahari yang ditafsirkan sebagai cahaya terang yang meletus secara tiba-tiba
dari permukaan matahari. Ia mampu menjejaskan sistem ionosfera bumi justeru mengganggu mana-mana arus yang
mengalir di lapisan tersebut. Kejadian ini dapat diperhatikan melalui pemerhatian data magnetometer yang dicerap
di bumi. Kesan umum suar suria adalah peningkatan kekonduksian ionosfera seterusnya meningkatkan keamatan arus
namun didapati terdapat beberapa suar suria mampu memberikan kesan sebaliknya. Terdapat kajian yang melaporkan
bahawa satu suar suria mampu meningkatkan keamatan arus di sesetengah kawasan dan pengurangan keamatan
pada kawasan yang lain. Kajian lepas pula lebih tertumpu kepada kesan suar suria pada kawasan sektor tertentu atau
setempat. Walau bagaimanapun, kajian ini mengambil pendekatan untuk menganalisis sifat suar suria dan kesannya
menggunakan taburan data yang lebih meluas iaitu melibatkan stesen magnetometer yang dipasang di lima sektor. Data
yang digunakan adalah daripada jaringan Magnetic Data Acquisition System/Circum Pan Magnetometer Network Pacific
(MAGDAS/CPMN) dan suar suria dikenal pasti melalui data fluks sinar-X yang dicerap daripada satelit Geostationary
Operational Environmental Satellite 15 (GOES 15). Keputusan kajian menunjukkan kesan suar suria yang tidak pernah
ditemui sebelum ini iaitu pengurangan keamatan arus pada semua data cerapan di khatulistiwa magnetik dan punca
yang dicadangkan adalah kewujudan arus elektrojet berlawanan. Selain itu, keputusan kajian turut mendapati bahawa
suar suria tersebut berlaku pada fasa pemulihan ribut geomagnet semasa soltis Jun dalam fasa suria menaik.
In this paper, four types of circular probability distribution were used to evaluate which circular probability distribution gives the best fitting for southwesterly Malaysian wind direction data, namely circular uniform distribution, von Mises distribution, wrapped-normal distribution and wrapped-Cauchy distribution. The four locations chosen were Alor Setar, Langkawi, Melaka and Senai. Two performance indicators or goodness of fit tests which are mean circular distance and chord length were used to test which distribution give the best fitting.
Forecasting a multiple seasonal data is differ from a usual seasonal data since it contains more than one cycle in a
data. Multiple linear regression (MLR) models have been used widely in load forecasting because of its usefulness in the
forecast a linear relationship with other factors but MLR has a disadvantage of having difficulties in modelling a nonlinear
relationship between the variables and influencing factors. Neural network (NN) model, on the other hand, is a good
model for modelling a nonlinear data. Therefore, in this study, a combination of MLR and NN models has proposed this
combination to overcome the problem. This hybrid model is then compared with MLR and NN models to see the performance
of the hybrid model. RMSE is used as a performance indicator and a proposed graphical error plot is introduce to see the
error graphically. From the result obtained this model gives a better forecast compare to the other two models.
The shoot tip explants of the tillered onion line Z-018 were used as experimental materials. The effects of colchicine
and pendimethalin on the induction of polyploid tillered onion were studied in vitro with different concentrations and
treatment time. Treatment with 250 μmol/L colchicine for 4 days caused a variant rate of 42.22% and a mortality rate
of 36.67%, whereas treatment with 30 μmol/L pendimethalin for 6 days caused a variant rate of 41.11% and a mortality
rate of 24.44%. Subsequent cytological identification showed that tetraploid plants were successfully induced by both
mutagens. Compared with the diploid plants, the tetraploid plants exhibited slower growth, thicker leaves, stems and
roots, larger stomatal apparatus and increased number of chloroplasts. In addition, the obtained tetraploid plants have
thicker tubular leaves, decreased number of tillers, larger bulbs and increased yield of the products. This provides the
basis for future research on tillered onion germplasm resources.
The Hibiscus sabdariffa var. UMKL (Roselle) investigated here may potentially be used as an alternative fibre source. To
the best of our knowledge, there was no study focusing on the genetics underlying the cellulose biosynthesis machinery
in Roselle thus far. This paper presents the results of the first isolation of the cellulose synthase gene, HsCesA1 from this
plant, which is fundamental for working towards understanding the functions of CesA genes in the cellulose biosynthesis
of Roselle. A full-length HsCesA1 cDNA of 3528 bp in length (accession no: KJ608192) encoding a polypeptide of 974
amino acid was isolated. The full-length HsCesA1 gene of 5489 bp length (accession no: KJ661223) with 11-introns
and a promoter region of 737 bp was further isolated. Important and conserved characteristics of a CesA protein were
identified in the HsCesA1 deduced amino acid sequence, which strengthened the prediction that the isolated gene being
a cellulose synthase belonging to the processive class of the 2-glycosyltransferase family 2A. Relative gene expression
analysis by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) on young leaf and stem tissues
found that HsCesA1 had similar levels of gene expression in both tissues. Phylogenetic and Blast analyses also supported
the prediction that the isolated HsCesA1 may play roles in the cell wall depositions in both leaf and stem tissues.
This study describes the development of a multimedia environmental fate and transport model of dichlorodiphenyltrichloroethane (DDT) at Sungai Sayong watershed. Based on the latest estimated DDT emission, the DDT concentrations in air, soil, water and sediment as well as the transfer processes were simulated under the equilibrium and steady-state assumption. Model predictions suggested that soil and sediment was the dominant sink of DDT. The results showed that the model predicted was generally good agreement with field data. Compared with degradation reaction, advection outflow was more important processes occurred in the model. Sensitivities of the model estimates to input parameters were tested. The result showed that vapour pressure (Ps) and organic carbon water partition coefficient (KOC) were the most influential parameters for the model output. The model output-concentrations of DDT in multimedia environment is very important as it can be used in future for human exposure and risk assessment of organochlorine pesticides (OCPs) at Sungai Sayong Basin.
Various natural biological conduits have been investigated to bridge peripheral nerve injury especially in critical
gap (greater than 3 cm in human). Autograft, the current gold standard, has several drawbacks including limited
availability of donor graft, donor-site morbidity and mismatch in size in clinical practices. The aim of this study was
to analyze the development of nerve conduit using decellularized human umbilical cord (HUC) artery seeded with
neurodifferentiated human MSCs (ndMSCs) in bridging peripheral nerve gap. Artery conduits obtained from HUC were
decellularized to remove native cells (n=3), then characterized by Hematoxylin and Eosin (H&E) staining and nuclei
counterstaining with DAPI. The decellularized artery conduit was measured for every 2 weeks until 12 weeks. Next,
mesenchymal stem cells (MSCs) were differentiated into neural lineage using 400 µg/mL of Centella asiatica. Then,
1.5×106
of MSCs or ndMSCs were seeded into decellularized artery conduit to study cell attachment. H&E staining
and nuclei counterstaining with DAPI showed that all cellular components were removed from the HUC arteries. The
decellularized artery conduit did not collapse and the lumen remained rigid for 12 weeks. Immunocytochemistry
analysis with neural markers namely S100β, P75 NGFR, MBP and GFAP showed that MSCs had differentiated into
neural lineage cells. H&E staining showed that the seeded MSCs and ndMSCs attached to the lumen of the conduits
as early as 2 days. In conclusion, this study showed that nerve conduit using decellularized HUC artery seeded with
neurodifferentiated human MSCs was successfully developed and have the potential to bridge critical nerve gap.
The suction between soil particles is the basis and core problem in the study of unsaturated soil. However, is the suction between soil particles just the matrix suction (which has been widely used since the discipline of unsaturated soil mechanics was established). In fact, the concept of matrix suction is from soil science and reflects the water-absorbing capacity of the soil. Matrix suction characterizes the interaction between soil particles and pore water rather than the interactions between soil particles, which were not in conformity with the principle of effective stress of soils. The suction of unsaturated soil, in essence, is the intergranular suction composed of absorbed suction and structural suction. In this paper, first, the basic concepts of absorbed suction and structural suction were briefly introduced. Then, with soil mechanics, powder science, crystal chemistry, granular material mechanics and other related disciplines of knowledge for reference, the quantitative calculation formulas were theoretically deduced for the absorbed suction for equal-sized and unequal-sized unsaturated soil particles with arbitrary packing and the variable structural suction for equal-sized unsaturated soil particles with arbitrary packing and unequal-sized unsaturated soil particles with close tetrahedral packing. The factors that influence these equations were discussed. Then, the shear strength theory of unsaturated soil was established based on the theory of intergranular suction through the analysis of the effective stress principle of unsaturated soil. This study demonstrates that the shear strength of unsaturated soil consists of three parts: The effective cohesive force, the additional strength caused by external loads and the strength caused by intergranular suction. The contribution of the three parts to the shear strength of unsaturated soil depends on the following influence factors: Soil type, confining pressure, water content and density. Therefore, these factors must be comprehensively considered when determining the strength of an unsaturated soil.
Formation lithology identification is an indispensable link in oil and gas exploration. Precision of the traditional recognition method is difficult to guarantee when trying to identify lithology of particular formation with strong heterogeneity and complex structure. In order to remove this defect, multivariate membership function discrimination method is proposed, which regard to lithology identification as a linear model in the fuzzy domain and obtain aimed result with the multivariate membership function established. It is indicated by the test on lower carboniferous Bachu group bioclastic limestone section and Donghe sandstone section reservoir on T Field H area that satisfactory accuracy can be achieved in both clastic rock and carbonate formation and obvious advantages are unfold when dealing with complex formations, which shows a good application prospect and provides a new thought to solve complex problems on oilfield exploration and development with fuzzy theory.