Abstract

A sampling rule and a stopping rule were developed for a sequential procedure used in point estimation. This sequential estimation method was applied to line and point transect sampling using the negative exponential key function. The results showed that the sequential estimation method was better than the conventional method in the following cases: accuracy for line transects at lower cost and accuracy for point transects; precision for both transects at lower cost; sample size for both transects at higher cost; the precision for point transects was also consistently better than the standard acceptable value. The convergence rate of the sequential estimation method was faster for line transects than for point transects in terms of accuracy and precision.

Index Terms

sequential estimation, distance sampling, line transects, point transects, negative exponential

Abstract

Preliminary investigation on the methanol extract of Shorea contorta bark exhibited an antibacterial activity against Staphylococcus aureus (17.3 mm zone of inhibition) and Mycobacterium phlei (24.3 mm zone of inhibition) using the agar-disk diffusion method. The methanolic extract also exhibited an antitubercular activity with 95% inhibition against Mycobacterium tuberculosis H37Rv strain at 128 μg/mL using the Microplate Alamar Blue Assay (MABA). Following a bioassay-guided fractionation approach, the methanolic extract was further fractionated and subjected to a series of chromatographic purification leading to the isolation and identification canaliculatol (1), a polyphenolic compound containing a resveratrol trimer.

Index Terms

Antimicrobial, Dipterocarpaceae, Polyphenol, Shorea contorta

Abstract

The study is conducted primarily to investigate the effect of steel shavings on the shear strength of RC beams; secondly, to identify at what specific percentage by weight of concrete mix will the steel shavings make a significant effect on the shear strength of RC beams; to learn about crack characteristics of RC beams with steel shavings focusing on crack width; and lastly, to derive an empirical formula and develop a nomogram that could be used to approximate the shear strength of the RC beams.

An experiment is conducted where twenty-five beam specimens are tested by applying a single point load until failure. Five sets of specimens are cast with 0%, 0.50%, 1.00%, 1.50% and 2.00% steel shavings by weight of concrete mix consisting of cement, fine and course aggregates and water.

The results of the experiments reveal that steel shavings at 1.00% increase the shear strength of RC beams; the addition of steel shavings, particularly at 0.50%, 1.50% and 2.00%, has a detrimental effect on the shear strength of RC beams; the formation of multiple short cracks are observed in the specimens with steel shavings which is an indication of the redistribution of stresses within the effective phase of the RC beams; the crack width of the RC beams with steel shavings is wider than that of the specimens without the steel shavings; the empirical formula (8), based on the cubic spline interpolation of mean shear strength, yields reliable approximation of the shear strength of RC beams at less than 1% error; the empirical formula (9) yields a reliable approximation of the shear value when compared to the actual shear at failure, with a mean percentage error of 2.35%; and the resulting nomogram from empirical equation (9) also yields a reliable approximation of shear as compared to the actual shear value with a mean percentage error of -4.22%.

Abstract

Oil spills are accidental releases of liquid petroleum hydrocarbon into the environment due to human activities, and it is a form of pollution. Rice hulls are agricultural wastes that can be used to absorb oil. Thus, becomes the aim of this study.

Silica powder is extracted and synthesized from rice hull using the precipitation method. SEM-EDX and FTIR were used to characterize the derive silica sample. To test the efficiency of the silica powder in oil absorption, motor gear oil was used. Five milliliter was placed in a dish and was carefully added with silica powder until it forms in lumps and with no traces of oil in the container. The Silica powder and oil mixture were weighed and divided in to 3. Using hexane extraction, the oil was removed from the silica powder. The supernatant solution was left to stand for a few hours to let the hexane evaporate. The mass of oil left was measured.

SEM confirmed the spongy and porous structure of silica powder from rice hull. Silicon and Oxygen show dominance in the EDX analysis which was probably due to silica. The FTIR results confirm the presence of the silica noting peaks at 467.96 and 1095.36 cm-1.

The total mass of silica powder carefully added to 5 ml of oil was 3.02449 g. The average holding capacity of the silica powder turned out to be 58.23%.

This study has shown that the silica powder from rice hull can be good oil absorbent. It is however recommended that studies be conducted for silica powder be chemically treated to become oleiphillic and hydrophobic and conduct further oil absorbency test in water.

Index Terms

rice hull ash, SEM, FTIR, silica

Abstract

Mixing of varieties of rice is rampant on our market today. This study motivates in determination of mixed rice based on the spectrum generated, in comparison with the unmixed to the mixed one. Samples used in this experiment are Young Master of Variety V10, Masipag and NFA. Samples are then mixed with other samples characterized using KBr pellet/ Disk technique, implored in Fourier Transform Infrared Spectroscopy. FTIR Spectrum gives almost the same spectrum, manifested by almost same peaks but different transmittance. However, samples are of different variety, there are wavenumbers that are significantly not seen from sample to sample.

Index Terms

Frequency, FTIR, Rice, Spectrum

Abstract

When tropical storm Washi (Sendong) hit Cagayan de Oro it leaves multitude of damages not only to properties but also to several thousands of lives. That weather event was considered rare in CDO but today some people panicked even with a minimal increase in precipitation or wind speed intensity. This study aims to analyze how the predictability of wind speed changes during tropical storm Washi. It also aims to determine how wind direction varies in that weather event. The results will give us a better understanding of the pattern of this weather element during normal and stormy days and thus may help us in finding relevant precautionary measures. The data were taken from the weather station of Xavier University – Ateneo de Cagayan (XUADC) through the Engineering Research Center (ERC). Wind speed and wind direction data for the whole month of December 2011 were used for the analysis. The predictability of wind speeds were measured by calculating the prediction error of the data on daily basis. This was done by making a prediction, and then calculating the difference between that prediction and the real output value then taking the mean of the absolute value of this difference for all the predictions. The prediction error is the ratio of that mean to the standard deviation of the data. Larger prediction error means lesser predictability while smaller prediction error means greater predictability. For wind direction variability, the 16 directions of the 16 point compass rose were converted to numerical values of 1 to 16 and then 0 was assigned for still wind. Then the data were plotted in SCILAB before being analyzed. Result on the wind speed predictability shows that wind speed is most predictable during the tropical storm. On the other hand, results on wind direction variability shows that during fair weather, wind is deflected at maximum angles of 22.50 to 900while on stormy day the maximum angle of deflection reaches 157.50. These results show that a change in wind pattern is evident during tropical storms.

Index Terms

Predictability, Tropical storm Washi, Wind direction, Wind speed

Abstract

Angiogenesis is a process involving the formation of new blood capillaries, which occurs in both physiological and pathological processes in animals and in humans. It is an important factor in wound healing, growth of adipose tissue, and as a component of the female menstrual cycle. In tumor progression, angiogenesis is a requirement for neoplastic growth and survival.

Angiogenic modulating substances were obtained from the bracket fungus Ganoderma applanantum through fractional polysaccharide (FPS) and supercritical carbon dioxide extraction (SF-CO2) protocols. Four crude polysaccharide extracts from the FPS and one polar extract from the SFE using high pressure CO2 (300 atm) at 40ºC, were tested for angiogenic modulation using the chick embryo chorioallantoic membrane (CAM) assay.

Three out of four crude polysaccharide residues showed significant inhibition on angiogenesis, whereas significant angiogenic stimulation was observed with the polar residue. This was statistically confirmed using a CRD factorial analysis of data obtained from the CAM assay.

This is the first study reported in the Philippines and elsewhere in the use of the CAM assay for determining the angiogenic modulating effects of Ganoderma applanatum extracts. It is possible that the elucidation of the chemical nature of the three polysaccharide residues exhibiting anti-angiogenic properties, may reveal a new class of anti-neoplastic natural products. On the other hand, the angiogenesis-promoting polar residue may find its practical medical application in the stimulation of organ survival after transplantation and as an adjunct treatment in paralysis, such as in cerbrovascular accidents (CVA).

Index Terms

chorioallantoic, Ganoderma, angiogenic

Abstract

Technological development in building construction is fast changing in response to concerns on urban sprawl, resource conservation and sustainable development. As such, this study is envisioned to develop a low-cost housing material utilizing solid waste-polystyrene (food packaging foam) and rice hulls. The concept is drawn from the commercial 3D panel in which mixed polystyrene and rice hulls are glued together to make an infill in lieu of the Styrofoam used in commercial boards.

The infill material is then sandwiched with welded wire and is plastered with concrete on all sides resulting to a modified 3D panel. After 28 days of curing, it is then tested under compressive and flexural loading.

Findings show that panels with wire gage #16 reveal an average flexural strength of 7.13 MPa which is 18.25 % greater than the commercial EVG 3D panel (control). Furthermore, under compressive loading, the prototypes with wire gage #16, likewise, exceeds at about 6.58% of its compressive strength compared to the control which is 4.27 MPa only.

Flexural test results show that CPF0001 obtained the highest value of deflection at about 60.07 mm at failure and 47.02 mm for CPF0002. On the other hand, under compressive test, CPC0001, CPC0002 and CPC0003 have mean vertical deflections at failure of 52.33 mm, 11.12 mm, and 14.87 mm, respectively and mean lateral deflections at failure of 0.12 mm, 7.74 mm and 0.35 mm, respectively. Further, the panels exhibit a critical buckling strength of 187212.439 kN.

The empirical formula, Equation 4.1 based on LAB Fit Curve Fitting V9.0.59, reveals a mean percentage error of –0.83% in approximating the flexural strength from the actual value, and Equations 4.2 and 4.3 show an average percentage error of -14.42% and -15.25%, respectively, in approximating compressive strength compared to the actual value.

The modified 3D panel costs Php 1080.86, which is Php 519.14 cheaper than the commercial 3D panel.

Index Terms

flexural, deflection, styrofoam

Abstract

Digital frontal face images of ninety-six (96) hypertensive and ninety-six (96) non-hypertensive adults were compared in this study. Each group was composed of fifty-four (54) females and forty-two (42) males. Forty-one (41) landmarks were manually positioned on the ventral part of the face. Using the software, SAGE, Procrustes superimposition, Procrustes ANOVA and Principal Component Analysis were applied to extract comparable shape information. Results of Procrustes ANOVA show that while individual variation is higher among non-hypertensive individuals, fluctuating asymmetry (FA) is very high in hypertensives. Principal Component Analysis specified the landmark displacements and the scatter plot from the first 2 principal components show the complete separation of the male and female hypertensive from the non-hypertensive male and female.

Index Terms

Procrustes, ANOVA, SAGE, morphometrics

Abstract

The study of a two cubic meter biogas digester using recycled high density polyethylene drums was carried out for household use. Hog manure of 1:2 (manure to water) proportion was used as a substrate. The digestion of the slurry was undertaken in a semi-continuous type of feeding. The biogas plant was designed and constructed to determine its performance daily on basis of gas production. Thus, important parameters that were monitored are: mass flow rate, optimum utilization time, gas analysis and financial analysis.

The daily gas production was obtained using a volume displacement method. The results showed that the average gas production was 444.33 liters per day at an average gas temperature and pressure of 27.30 0C and 13.41 cm of water (1.314 KPa), respectively. It was disclosed that the conditions within the digester suitable for the anaerobic microbes where under mesophillic temperature .

Optimum time utilization of the gas was tested for cooking in three consecutive days and it was found out that the average utilization per day lasted for three hours and forty two minutes.

Gas analysis showed that reaches as high as 69% and drops to 26.6%. These were obtained by using Orsat gas analyzer.

The mass flow rate was determined using the ideal gas equation and it was found to be equal to 0.437 kg/m3.

Financial analysis revealed that the total cost of investment can be recovered in 3.94 years with an expected return of investment about 25.38%.

Index Terms

biogas, polyethylene, portagas, displacement