Properties of hydroxyapatite synthesize by wet chemical method

S. Ramesh,S. Adzila,C.K.L. Jeffrey,C.Y. Tan,J. Purbolaksono,A.M. Noor,M.A. Hassan,I. Sopyan,W.D. Teng 한양대학교 세라믹연구소 2013 Journal of Ceramic Processing Research Vol.14 No.4

The sintering behavior of a commercial HA and synthesized HA was investigated over the temperature range of 700 o C to 1400 o C in terms of phase stability, bulk density, Young’s modulus and Vickers hardness. In the present research, a wet chemical precipitation reaction was successfully employed to synthesize a submicron, highly crystalline, high purity and single phase stoichiometric HA powder that is highly sinteractive particularly at low temperature regimes below 1100 o C. It has been revealed that the sinterability of the synthesized HA was significantly greater than that of the commercial HA. The temperature for the onset of sintering and the temperature required to achieve densities above 98% of theoretical value were approximately 150 o C lower for the synthesized HA than the equivalent commercial HA. Nevertheless, decomposition of HA phase upon sintering was not observed in the present work for both powders.

Strength loss contributions during stages of heating, retention and cooling regimes for concretes

Yaragal, Subhash C.,Warrier, Jishnu,Podila, Ramesh Techno-Press 2015 Advances in materials research Vol.4 No.1

Concrete suffers strength loss when subjected to elevated temperatures during an accidental event such as fire. The loss in strength of concrete is mainly attributed to decomposition of C-S-H gel and release of chemically bound water, which begins when the temperature exceeds $500^{\circ}C$. But it is unclear about how much strength loss occurs in different stages of heating, retention and cooling regimes. This work is carried out to separate the total strength loss into losses during different stages of heating, retention and cooling. Tests were carried out on both Ordinary Portland Cement (OPC) based concrete and Ground Granulated Blast Furnace Slag (GGBFS) blended concrete for $200^{\circ}C$, $400^{\circ}C$, $600^{\circ}C$ and $800^{\circ}C$ with a retention period of 1 hour for each of these temperature levels. Furnace cooling was adopted throughout the experiment. This study reports strength loss contribution during heating, retention and cooling regimes for both OPC based and GGBFS based concretes.

Principal Component Analysis and Molecular Characterization of Reniform Nematode Populations in Alabama

Nyaku, Seloame T.,Kantety, Ramesh V.,Cebert, Ernst,Lawrence, Kathy S.,Honger, Joseph O.,Sharma, Govind C. The Korean Society of Plant Pathology 2016 Plant Pathology Journal Vol.32 No.2

U.S. cotton production is suffering from the yield loss caused by the reniform nematode (RN), Rotylenchulus reniformis. Management of this devastating pest is of utmost importance because, no upland cotton cultivar exhibits adequate resistance to RN. Nine populations of RN from distinct regions in Alabama and one population from Mississippi were studied and thirteen morphometric features were measured on 20 male and 20 female nematodes from each population. Highly correlated variables (positive) in female and male RN morphometric parameters were observed for body length (L) and distance of vulva from the lip region (V) (r = 0.7) and tail length (TL) and c' (r = 0.8), respectively. The first and second principal components for the female and male populations showed distinct clustering into three groups. These results show pattern of sub-groups within the RN populations in Alabama. A one-way ANOVA on female and male RN populations showed significant differences ($p{\leq}0.05$) among the variables. Multiple sequence alignment (MSA) of 18S rRNA sequences (421) showed lengths of 653 bp. Sites within the aligned sequences were conserved (53%), parsimony-informative (17%), singletons (28%), and indels (2%), respectively. Neighbor-Joining analysis showed intra and inter-nematodal variations within the populations as clone sequences from different nematodes irrespective of the sex of nematode isolate clustered together. Morphologically, the three groups (I, II and III) could not be distinctly associated with the molecular data from the 18S rRNA sequences. The three groups may be identified as being non-geographically contiguous.

Principal Component Analysis and Molecular Characterization of Reniform Nematode Populations in Alabama

Seloame T. Nyaku,Ramesh V. Kantety,Ernst Cebert,Kathy S. Lawrence,Joseph O. Honger,Govind C. Sharma 한국식물병리학회 2016 Plant Pathology Journal Vol.32 No.2

U.S. cotton production is suffering from the yield losscaused by the reniform nematode (RN), Rotylenchulusreniformis. Management of this devastating pest is ofutmost importance because, no upland cotton cultivarexhibits adequate resistance to RN. Nine populationsof RN from distinct regions in Alabama and onepopulation from Mississippi were studied and thirteenmorphometric features were measured on 20 male and20 female nematodes from each population. Highly correlatedvariables (positive) in female and male RN morphometricparameters were observed for body length(L) and distance of vulva from the lip region (V) (r = 0.7)and tail length (TL) and c’ (r = 0.8), respectively. Thefirst and second principal components for the femaleand male populations showed distinct clustering intothree groups. These results show pattern of sub-groupswithin the RN populations in Alabama. A one-wayANOVA on female and male RN populations showedsignificant differences (p ≤ 0.05) among the variables.Multiple sequence alignment (MSA) of 18S rRNA sequences(421) showed lengths of 653 bp. Sites within thealigned sequences were conserved (53%), parsimonyinformative(17%), singletons (28%), and indels (2%),respectively. Neighbor-Joining analysis showed intraand inter-nematodal variations within the populationsas clone sequences from different nematodes irrespectiveof the sex of nematode isolate clustered together. Morphologically, the three groups (I, II and III) couldnot be distinctly associated with the molecular datafrom the 18S rRNA sequences. The three groups maybe identified as being non-geographically contiguous.

서비스 산업의 네팔 경제에 대한 기여도

( Ramesh C Chitrakar ) 전남대학교 지역개발연구소 2014 지역개발연구 Vol.46 No.1

네팔 경제에서 서비스 산업의 중요도는 갈수록 증가하고 있다. 다른 국가들과 마찬가지로, 서비스 산업은 국내 총 생산, 고용, 국제 무역, 외국인 투자 등에서 큰 비중을 차지한다. 본 연구는 위에 언급한 다양한 네팔의 경제 지표들에 대한 서비스산업의 역할을 분석했다. 또한 본 연구는 네팔의 빈곤 감퇴와 고용 창출, 그리고 성장과 개발에 대한 역할을 분석했다. 본 연구는 국가 발표 자료와 국제 발표 자료에 기초해서 진행되었다. 국내 총 생산에 대한 1차, 2차 3차 서비스 산업의 기여도는 각각 35.3%, 14.4%, 그리고 50.3%이며 이 기여도 총합은 국내 총 생산의 50%를 상회하는 수치이다. 건설 산업은 WTO 분류에 따라 서비스 산업에 포함되지 않았다. 관광 산업에서도 호텔 숙박업과 요식업만 포함되어 과소 추정되었다고 할 수 있다. 서비스 무역 산업에 대해서는, 네팔의 서비스 산업은 2004년까지는 수출이 수입을 초과하였으며, 2005년부터 2010년까지는 반대의 상황이 발생했으나 다시 2011년부터 개선되었다. 서비스 산업에 의해 네팔의 최대 수출 산업은 여행 산업이고 그 뒤를 통신과 타 산업 수출이 뒤를 잇고 있다. 수입에서도 역시 여행 산업이 가장 큰 비중을 차지하고 수송 서비스가 그 다음을 잇고 있다. 네팔의 서비스 무역은 재화 무역보다 훨씬 더 균형을 보이고 있다. 서비스 산업의 중요성에도 불구하고, 서비스 산업에는 몇 가지 장벽이 있다. 국내서비스 산업에 대한 규제가 심각한 것으로 드러났다. 그리고 많은 고려해야 할 교차이슈들이 존재한다. 서비스 산업의 기여는 이러한 장벽들이 제거될 때 더 개선될 수 있을 것이다. The importance of service sector in Nepal has increased over the years. The sector, as in other countries, has emerged as a major contributor to GDP, employment, international trade, foreign investment and also balance of payments. The present article examines and analyses the role the service sector is playing in the development of Nepal in terms these various indicators mentioned above. The article also examines the role of the sector in terms of poverty reduction, employment generation and growth and development of the country. The article is based on the review of literatures available nationally and internationally. The data source is derived both through printed source and internet search. The study found a gradual change in the economic structure of Nepal. The contribution of primary, secondary, and tertiary sectors stood at 35.3 percent, 14.4 percent, and 50.3 percent respectively which has clearly shown the contribution to GDP exceeding 50 percent. The construction sector is not kept under service sector though the WTO classification has. In tourism also, only the contribution of hotels and restaurants is included implying the under estimation of this sector. In terms of contribution to trade, Nepal`s services exports exceeded imports until 2004 with a reverse situation for 2005 to 2010, but improved again from 2011 onwards. By services categories, the country`s highest export is in travel followed by export of communication and other business services. In imports, highest import is travel, followed by transport services. Nepal`s service trade is found to be more balanced than commodity trade. The labour service (‘remittance’) has remained important in Nepal`s export basket. Nepal has been in positive balance of payments due in no small part by the fast-growing remittances of temporary Nepalese migrant. In terms of the service sector contribution to industrial development, majority of industries obtaining license from the GoN are service oriented though the government`s classification is not as per international practice. Foreign investment in Nepal is also contributing in terms of employment in the country; with an employment of 106 services oriented and 64 tourism firms in the FY 2011/12. The employment contribution of these two services sectors is 5662 persons out of the total employment of 9050 generated by foreign investment. In spite of the importance of the service sector, there are some barriers to service sector. The domestic service legislation and regulations are found to be most critical. There are also a number of cross-cutting issues. The contribution of the service sector could be improved if such barriers can be removed.

Effect of Feeding Grape Pomace on Selected Metabolic Parameters Associated with High Fructose Feeding in Growing Sprague–Dawley Rats

Ramesh C. Khanal,Luke R. Howard,Theodore J. Rogers,Samuel E. Wilkes,Ishwori B. Dhakal,Ronald L. Prior 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.12

The effect of feeding grape pomace on certain metabolic parameters associated with high fructose (HF)feeding was studied. Forty male growing Sprague–Dawley rats were randomly assigned into groups: (1) control; (2) HF; (3)HF with low-level (1.5% of diet) grape pomace (HF + LP), and (4) HF with high-level (5.0% of diet) grape pomace (HF + HP). The HF + LP and HF + HP diets provided 115 and 218 mg of procyanidins/kg, respectively. Compared with the controls, HFfed animals consumed less and were smaller, whereas animals in the HF + LP and HF + HP groups were in between. A similar trend was observed for abdominal fat and abdominal fat as a percentage of body weight. No change in heart or kidney weight occurred. Liver weight as a percentage of body weight was higher for animals when fructose was included in the diet compared with those on control diet, and inclusion of grape pomace had no effect. Fasting plasma glucose, insulin, and triglyceride levels tended to be higher in animals fed HF diet, and grape pomace reduced their levels to values similar to the control animals. Compared with control animals, HF-fed animals had higher weekly postprandial plasma triglycerides, which were reduced by feeding grape pomace, but no change in plasma cholesterol was observed. Glucose intolerance was observed in animals fed HF diet and was accompanied by a 25% increase in homeostatic model assessment (HOMA) of insulin resistance. Inclusion of grape pomace increased glucose tolerance and insulin sensitivity. No significant change (P > .1) in HOMA of β-cell function or Quantitative Insulin-Sensitivity Check Index was observed. Overall, HF diet did not produce as strong a response of metabolic syndrome as has been shown in the literature. The inclusion of grape pomace in the diet was effective in modulating some aspects of metabolic parameters associated with metabolic syndrome, and the higher level of grape pomace in the diet produced a slightly better response than the lower level.

Evaluation of Polyvoltine Hybrids Based on Silk Productivity in Silkworm, Bombyx mori L.

C. G. P. Rao,Chandrashekaraiah,C. Ramesh,K. Ibrahim Basha,S. V. Seshagiri,H. Nagaraju 한국잠사학회 2004 International Journal of Industrial Entomology Vol.8 No.2

Polyvoltine silkworm breeds/hybrids play an important role in tropical sericulture. In the process of synthesizing more potential polyvoltine hybrids (polyvoltine ´ bivoltine) of superior quantity and quality, the Andhra Pradesh State Sericulture Research and Development Institute (APSSRDI) has developed 8 promising polyvoltine breeding lines (SDMG2, APM16, APM15, APM14, APM5, RM2, APM3, APM13). In order to study their hybrid vigour and performance, these breeds were crossed with 4 potential bivoltine testers (SDD1, SDD2, SDD3, APS8), and 32 different hybrid combinations were prepared and evaluated for their mid parent heterosis (MPH) and better parent heterosis (BPH) of silk productivity. Since silk is the ultimate product required for commercial purpose, based on silk productivity and its heterosis, three superior polyvoltine hybrid combinations namely RM2 ´ APS8 (24.3%), APM3 ´ APS8 (12.4%) and APM15 ´ SDD2 (10.8%) were adjudicated as potential heterotic hybrid combinations of superior silk yield and hence recommended for further large scale field trails and commercial exploitation.

Low-temperature sintering and prolonged holding time on the densification and properties of zirconia ceramic

C.H. Ting,S. Ramesh,C.Y. Tan,N.I. Zainal Abidin,W.D. Teng,I. Urriés,L.T. Bang 한양대학교 세라믹연구소 2017 Journal of Ceramic Processing Research Vol.18 No.8

In the present work, the effect of low temperature sintering, focusing on varying the sintering holding times on the mechanicalproperties, microstructure and low temperature degradation behavior of undoped and MnO2-doped Y-TZP ceramics wereinvestigated. Green samples were sintered at temperatures ranging from 1100 to 1250 oC at varying holding times rangingfrom 12 min. to 480 min. The sintered bodies were characterized in terms of bulk density, Vickers hardness, fracturetoughness, phase stability and grain size. The results indicated that the relative density of above 95%, Vickers hardness of 14GPa and fracture toughness of 5 MPam1/2 were obtained when sintered at lower sintering temperature (below 1250 oC) andlonger sintering times for MnO2-doped Y-TZP samples. Grain growth was marginal and the average grain size of all samplesranged between 0.14 and 0.28 µm. The results indicated that the grain growth kinetics was influenced mainly by the sinteringtemperature and not by the sintering holding time. The addition of MnO2 was found to be beneficial in enhancing densificationand mechanical properties of Y-TZP particularly at low sintering temperature of 1100 oC and low holding time of 12 min. Thelow-temperature degradation experiment conducted in superheated steam indicated that all the samples did not transformedto the monoclinic symmetry, attributed mainly to the lower grain size sintered at relatively low sintering temperatures

Effect of Dietary Blueberry Pomace on Selected Metabolic Factors Associated with High Fructose Feeding in Growing Sprague–Dawley Rats

Ramesh C. Khanal,Luke R. Howard,Samuel E. Wilkes,Theodore J. Rogers,Ronald L. Prior 한국식품영양과학회 2012 Journal of medicinal food Vol.15 No.9

An experiment was conducted to study the protective effect of feeding extruded and unextruded blueberry pomace (BBP) on selected metabolic parameters associated with metabolic syndrome in a model of high fructose (HF)-fed growing Sprague–Dawley rats. Treatments were as follows: (1) control (modified AIN-based diet); (2) HF diet (AIN diet with 58% fructose); (3) HF diet with 1.5% unextruded BBP; (4) HF diet with 1.5% extruded BBP; (5) HF diet with 3% unextruded BBP; and (6) HF diet with 3% extruded BBP. Compared with the control, HF feeding increased fasting plasma insulin and fasting and postprandial plasma triglycerides as well as homeostatic scores of insulin resistance and β-cell function, but not weight gain, diet intake and efficiency, abdominal fat, oral glucose tolerance, and fasting and postprandial plasma glucose, cholesterol, and leptin levels. Inclusion of unextruded or extruded BBP was effective in minimizing or ameliorating the fructose-induced metabolic anomalies, except postprandial plasma triglycerides, especially at 3% of the diet. In addition, unextruded or extruded BBP at 3% of the diet was also able to reduce plasma cholesterol and abdominal fat relative to the HF control, which may impart additional health benefits. Compared with the control, inclusion of unextruded or extruded BBP at both 1.5% and 3% resulted in lower total fat weight, and animals fed a diet supplemented with 3% unextruded BBP in fasting state or 3% unextruded BBP in fed state had lower leptin levels than the control. This is the first study demonstrating the beneficial effects of feeding blueberry pomace on health.

Analyzing Survival Data by Proportional Reversed Hazard Model

Ramesh C. Gupta,Han Wu 한국신뢰성학회 2001 International Journal of Reliability and Applicati Vol.2 No.1