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International Journal of Organic Chemistry 2014年第5期4卷 339-346页

作者： Adnan A. S. El Khaldy Florence okafor Alaa M. Abu Shanab Department of Physics Chemistry and Mathematics College of Engineering Technology and Physical Sciences Alabama A&M University Normal AL USA Department of Biological & Environmental Sciences College of Agricultural Life and Natural Sciences Alabama A&M University Normal AL USA Chemistry Department Al-Aqsa University Gaza Palestine

A new complexes of Cp2Ti[S2P(OR)2]2 (where R = Et, Pr-n, Pr-i, Bu-i and Ph) and Cp2Ti[S2POGO]2 (where G = -CH2CMe2CH2-, -CH2CEt2CH2- and -CMe2CMe2-) were prepared by the dropwise addition of the appropriate O,O’-dialkyl or -alkylenedithiophosphoric acid to biscyclopentadienyl titanium dichloride in 1:2 molar ratio and refluxed in benzene solution. These novel deep red colored complexes were characterized by elemental analyses, molecular weight measurements and spectroscopic techniques (IR., nMR 1H, 13C and 31P nMR). These titanium (IV) dithio complexes have also been screened for their antibacterial activities.

关键词： Titanium (IV) Dialkyl and Alkylenedithiophosphate Complexes

Long term oncological outcome of laparoscopic techniques in pancreatic cancer

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World Journal of Gastrointestinal Endoscopy 2018年第12期10卷 383-391页

作者： Trond Buanes Bjorn edwin Department of Gastroenterological Surgery Division of CancerSurgery and TransplantationInstitute of Clinical MedicineFaculty of MedicineOslo University HospitalOslo N-0424Norway the Intervention Centre and Department of Hepato-Pancreatico-Biliary Surgery Institute of Clinical MedicineFaculty of MedicineOslo University HospitalOslo N-0424Norway

The laparoscopic technique in distal pancreatic resection(LDP) has been widely accepted, and outcome data support the hypothesis that survival is improved,partly due to improved postoperative safety and recovery, thus optimizing treatment with adjuvant chemotherapy. But laparoscopic pancreaticoduodenectomy(LPD or Whipple-procedures) has spread more slowly, due to the complexity of the procedure. Surgical safety has been a problem in hospitals with low patient volume, resulting in raised postoperative mortality, requiring careful monitoring of outcome during the surgical learning curve. Robotic assistance is expected to improve surgical safety, but data on long term oncological outcome of laparoscopic Whipple procedures with or without robotic assistance is scarce. Future research should still focus surgical safety, but most importantly long term outcome, recorded as recurrence at maximal follow up or-at best-overall long term survival(OS). Available data show median survival above 2.5 years, five year OS more than 30% after LDP even in series with suboptimal adjuvant chemotherapy. Also after LPD, long term survival is reported equal to or longer than open resection. However, surgical safety during the learning curve of LPD is a problem, which hopefully can be facilitated by robotic assistance. Patient reported outcome should also be an endpoint in future trials, including patients with pancreatic ductal adenocarcinoma.

关键词： Chemotherapy Endpoint Imaging Laparoscopic surgery Long term outcome Overall survival Pancreatic cancer Robotic assistance

Petroleum Source-Rock Evaluation and Hydrocarbon Potential in Montney Formation Unconventional Reservoir, northeastern British Columbia, Canada

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natural Resources 2017年第11期8卷 716-756页

作者： edwin I. Egbobawaye Department of Earth and Atmospheric Sciences University of Alberta Edmonton Canada

Source-rock characteristics of Lower Triassic Montney Formation presented in this study shows the total organic carbon (TOC) richness, thermal maturity, hydrocarbon generation, geographical distribution of TOC and thermal maturity (Tmax) in Fort St. John study area (T86n, R23W and T74n, R13W) and its environs in northeastern British Columbia, Western Canada Sedimentary Basin (WCSB). TOC richness in Montney Formation within the study area is grouped into three categories: low TOC ( 3.5 wt%), and high TOC (>3.5 wt% %). Thermal maturity of the Montney Formation source-rock indicates that >90% of the analyzed samples are thermally mature, and mainly within gas generating window (wet gas, condensate gas, and dry gas), and comprises mixed Type II/III (oil/gas prone kerogen), and Type IV kerogen (gas prone). Analyses of Rock-Eval parameters (TOC, S2, Tmax, HI, OI and PI) obtained from 81 samples in 11 wells that penetrated the Montney Formation in the subsurface of northeastern British Columbia were used to map source rock quality across the study area. Based on total organic carbon (TOC) content mapping, geographical distribution of thermal maturity (Tmax) data mapping, including evaluation and interpretation of Rock-Eval parameters in the study area, the Montney Formation kerogen is indicative of a pervasively matured petroleum system in the study area.

关键词： Petroleum Source-Rock Rock-Eval Oil and Gas Kerogen Vitrinite Reflectance Hydrocarbon Reservoir Montney Formation Geology TOC Tmax Pyrolysis Hydrocarbon Generation British Columbia Western Canada Sedimentary Basin WCSB

The Frequency of Survivorship in Heterozygous Diploids of Cdc13-1exo1Δ Mutants of S. cerevisiae Is One Survivor Cell in 72 Cells/Generation at 36°C

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Advances in Bioscience and Biotechnology 2022年第11期13卷 469-478页

作者： Sixtus A. okafor Patrick U. Agbasi Oladimeji T. Azeez Samuel C. Iwuji Luvia U. Ezeamaku Felicity n. Arukalam Ebere O. Eziefuna Department of Biomedical Technology Federal University of Technology Owerri Nigeria Department of Prosthetic and Orthortic Federal University of Technology Owerri Nigeria Department of Polymer & Textile Engineering Federal University of Technology Owerri Nigeria

Telomeres cap ends of eukaryotic chromosomes prevent them from degradation and ensure genomic stability. Cdc13 is an essential telomere recruitment and maintenance protein. A temperature-sensitive point mutation in cdc13 gene leads to telomere impairment, giving rise to cdc13-1 mutants that suffer lethality at enhanced temperatures. Deleting Exo1 gene from these mutants, however, leads to the emergence of temperature-tolerant mutants called survivors. Yeasts are known to exist as either diploids or haploids. These yeast genotypes generate survivors. The frequency of survivorship in the haploid genotype is one cell in 104 cells/generation at 36°C, however, the frequency at which they emerge in their diploid counterparts at the same temperature is not known. In this study, we investigated the frequency of Survivorship in heterozygous diploids of cdc13-1exo1Δ mutants of S. cerevisiae at 36°C. Diploids were constructed by mating haploid strains of opposite mating type cdc13-1 exo1:LEU strains with strains of cdc13-1 exo1:HIS. The crosses were 1296 × 3181, 2561 × 3182, 1296 × 3182 and 2561 × 3181. Genetic markers and phenotypic appearance were considered while mating the mutant cells. Using a stick, a smear of one haploid strain was made on each YEPD plate labelled C2, C8, C9, D1, D14, and D15. A smear of another opposite mating type was made on the previous strain. They were mixed and allowed to mate overnight, before culturing on media lacking Luecine and Histidine (-L and -H). Survivors were generated by culturing these diploids at 36°C. Using SPSS 20.0 software for windows SPSS, 2011, the frequency was determined as one Survivor cell in 72 cells/generation, as their frequency of survivorship averaged 5.9 × 10-5 ± 0.04.

关键词： Telomere Diploids Haploids Mutation Survivors Frequency Cdc13

n-acetyl proline-glycine-proline: implications for neurological disorders

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neural Regeneration Research 2016年第6期11卷 898-899页

作者： Jeff W.Hill edwin M.nemoto Department of neurosurgery University of New Mexico Health Sciences Center

n-acetyl proline-glycine-proline（ac-PGP）is a matrix-derived chemoattractant,or matrikine,produced by the degradation of ***-PGP was first identified in studies of alkali eye injury in rabbits（Pfister et al.,1995）.

关键词： proline glycine acetyl neurological neuronal collagen neutrophil alkali potent chemokine

Mild Steel Corrosion Mitigation in Sulphuric Acid via Benign Isolated Phytochemicals from <I>Viscum album</I>

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Journal of Materials Science and Chemical Engineering 2018年第4期6卷 132-146页

作者： n. E. nya A. I. Ikeuba P. C. okafor B. U. Ugi V. M. Bassey A. I. Obike Corrosion and Electrochemistry Research Group Department of Pure and Applied Chemistry University of Calabar Calabar Nigeria Department of Chemistry Abia State University Uturu Nigeria

We present the evaluation of four Eco-friendly corrosion inhibitors for the corrosion mitigation of mild steel in acid media. The corrosion inhibition of mild steel by ethanol extracts from Viscum album (EEVA) and some of its isolated phytochemical components;phytates extract (PEVA), saponins extract (SEVA), and flavonoids extracts (FEVA) have been studied using gravi-metric and gasometric techniques. The results of the study reveal that these ecofriendly and benign extracts function as good inhibitors for mild steel corrosion in sulphuric acid. Inhibition efficiency of the extracts increases with inhibitor concentration and temperature rise. The trend of inhibition efficiency in lower inhibitor concentration is EEVA > PEVA > SEVA > FEVA and at higher concentration, the order was SEVA > PEVA > EEVA > FEVA. The presence of the plant extracts decreases the corrosion activation energy in the solution which indicates chemical adsorption mechanism. The adsorption of the components of the extracts is consistent with Temkin isotherm. The interaction between the isolated extracts is synergistic at lower inhibitor concentration and antagonistic at higher concentrations. The Kads values for PEVA and SEVA are higher than those of EEVA and FEVA. This implies that PEVA and SEVA are more efficiently adsorbed on the mild steel surface.

关键词： Acid Corrosion Mild Steel Viscum album Corrosion Inhibition Phytochemicals

Any Hamiltonian System Is Locally Equivalent to a Free Particle

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World Journal of Mechanics 2012年第5期2卷 246-252页

作者： Elizabeth Galindo-Linares Esperanza navarro-Morale Gilberto Silva-Ortigoza Román Suárez-Xique Magdalena Marciano-Melchor Ramón Silva-Ortigoza edwin Román-Hernández CIDETEC-IPn. Departamento de Posgrado. área de Mecatrónica. Unidad Profesional Adolfo López Mateos. C.P. México D.F. México Facultad de Ciencias Físico Matemáticas de la Benemérita Universidad Autónoma de Puebla Apartado Postal Puebla Pue. México Universidad del Istmo Departamento de Matemáticas Aplicadas Cd. Universitaria Tehuantepec Oax. México

In this work we use the Hamilton-Jacobi theory to show that locally all the Hamiltonian systems with n degrees of freedom are equivalent. That is, there is a canonical transformation connecting two arbitrary Hamiltonian systems with the same number of degrees of freedom. This result in particular implies that locally all the Hamiltonian systems are equivalent to that of a free particle. We illustrate our result with two particular examples;first we show that the one-dimensional free particle is locally equivalent to the one-dimensional harmonic oscillator and second that the two-dimensional free particle is locally equivalent to the two-dimensional Kepler problem.

关键词： Hamiltonian System Canonical Transformation

First Serological Evidence of Borna Disease Virus in Healthy Horses from Yucatan, Mexico

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Advances in Microbiology 2016年第7期6卷 489-494页

作者： Marco Torres-Castro Henry noh-Pech edwin Gutiérrez-Ruiz Julián García-Rejón Carlos Machain-Williams Jorge Zavala-Castro Fernando I. Puerto Centro de Investigaciones Regionales “Dr. Hideyo noguchi” Universidad Autónoma de Yucatán Mérida México Campus de Ciencias Biológicas y Agropecuarias Universidad Autónoma de Yucatán Mérida México

Borna Disease Virus (BDV) causes a progressive non-suppurative meningoencephalitis that sometimes occurs in mortality;this disease has been reported for over two centuries ago in horses, sheep and cats in Central Europe and some regions of Asia. Currently, it is known that it causes neurological symptoms in various species of vertebrates including human beings. In Yucatan, Mexico, there is a single serological report about the circulation of BDV in schizophrenia patients;however, nothing is known about the circulation in animals. We obtained serum samples of 100 horses without apparent clinical signs caused by BDV infection, from various sites in the region. Antibodies against BDV were detected by electrochemiluminescence immunoassay (ECLIA) method with three recombinant proteins: BDV p24, BDV p40 and BDV p10 as antigens;obtaining a high seroprevalence of 44% (44/100). This study generates the first report of the probable activity of the BDV in healthy horses in Mexico and has expanded the infiltration area of BDV in the world. nevertheless, several molecular investigations are required to detect BDV-RnA circulating and find sequences for clarification of the origin of BDV in Mexican horses.

关键词： Borna Disease Virus Electrochemiluminescence Immunoassay Healthy Horses Yucatan Mexico

Household Waste Management;Voices of Residents of Anaocha Local Government Area of Anambra State, nigeria

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Journal of Environmental Protection 2015年第12期6卷 1394-1401页

作者： E. C. Azuike S. A. nwabueze P. E. Onyemachi B. n. Egenti K. C. okafor R. C. Aniemena I. n. Udedibia J. O. nwodo Department of Community Medicine Nnamdi Azikiwe University Teaching Hospital Nnewi Nigeria Foundation for Health and Development in nigeria Department of Community Medicine Abia State University Aba Nigeria Department of Community Medicine University of Abuja Abuja Nigeria Department of Public Health Federal Medical Centre Keffi Nigeria Faculty of Medicine Nnamdi Azikiwe University Awka Nigeria

Background: Waste management is the generation, prevention, characterization, monitoring, treatment, handling, reuse and residual disposition of social waste. The various methods of waste disposal include: recycling, composting, barging, burying, landfills method, incineration, and the use of mechanical destructors. Objective: The aim of this study was to assess the knowledge, attitude and practice of house hold waste management among the respondents and the factors affecting their choice of method. Methodology: This was a cross sectional descriptive study. There were 270 respondents. The study was carried out among households in Anaocha LGA of Anambra state. The study made use of a semi-structured interviewer administered questionnaire. Result: Majority had good knowledge of waste management and portrayed good attitude towards waste management practices. The commonest method of waste disposal practiced by the community was burning and majority practiced the various methods because the methods were convenient for them. Conclusion: The study showed that people, despite having good knowledge and attitude towards waste management still practiced wrong methods.

关键词： Household Waste Management

Survival after resection of colorectal liver metastases in octogenarians and sexagenarians compared to their respective age-matched national population

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Hepatobiliary Surgery and nutrition 2018年第4期7卷 234-241页

作者： Kristoffer Watten Brudvik Bard Rosok Usha naresh Sheraz Yaqub Asmund Avdem Fretland Knut Jorgen Labori Bjorn edwin Bjorn Atle Bjornbeth Department of Hepato-Pancreato-Biliary Surgery Oslo University HospitalOsloNorway The Intervention Centre Oslo University HospitalOsloNorway Institute for Clinical Medicine University of OsloOsloNorway

Background: The aim of the current study was to investigate survival after resection of colorectal liver metastases (CLM) in octogenarians. The survival of octogenarian patients was compared to the survival of the national population of octogenarians and the survival of sexagenarians, the latter representing the average-age patient undergoing resection of CLM. Methods: Octogenarian and sexagenarian were defined as person 80–89 and 60–69 years of age, respectively. Survival analyses of patients who underwent resection of CLM between 2002 and 2014 were performed. Data from Statistics norway were used to estimate the survival of the age-matched national population of octogenarians (ageM-Octo) and the age-matched national population of sexagenarians (ageM-Sexa). Results: During the study period, 59 octogenarians underwent resection of CLM. The majority of patients underwent a minor liver resection (n=50). In octogenarians, the 5-year survival was 32.5% and 66.3%[difference, 33.8 percentage points (pp)] in patients and ageM-Octo, respectively. The 10-year survival was 14.1% and 31.2% (difference, 17.1 pp) in patients and ageM-Octo, respectively. In sexagenarians, the 5-year survival was 50.9% and 96.2% (difference, 45.3 pp) in patients and ageM-Sexa, respectively. The 10-year survival was 35.7% and 90.3% (difference, 54.6 pp) in patients and ageM-Sexa, respectively. The 5-year cancer-specific survival and 5-year recurrence-free survival (RFS) after resection of CLM in octogenarians were 43.1% and 32.9%, respectively. Conclusions: After resection of CLM, the survival was poorer in octogenarians than in sexagenarians. However, the difference between the survival curves of patients and their age-matched population was smaller in octogenarians. In practice, this finding may indicate a greater benefit of resection in the elderly than the survival rates alone would suggest.

关键词： Liver resection elderly octogenarians colorectal liver metastases (CLM) survival