Development of palladium nanoparticles based catalysts for aerobic oxidation of 5-hydroxymethylfurfural and glycerol

Palladium nanoparticles were synthesized by the polyol method. The prepared NPs were deposited onto supports and applied in 5-hydroxymethylfurfural (HMF) and glycerol (GLY) oxidation. A high yield of 2,5-furandicarboxylic acid > 90 % connected with a relatively stable catalytic performance was obtained by HMF oxidation on a Pd/ZrO2/La2O3. A lactic acid yield of 75 % was obtained by GLY oxidation on a Pd-Ag/TiO2 which showed also a stable catalytic performance when the catalyst was recycled. The prepared catalysts were characterized by various methods before and after the oxidation reactions

The comprehensive rural development programme as a vehicle for enhancing stakeholder participation in rural governance: a case study of Dysselsdorp in the Western Cape Province, South Africa

Magister Philosophiae (Land and Agrarian Studies) - MPhil(LAS)The thesis seeks to investigate the extent to which the Comprehensive Rural Development Programme (CRDP) has succeeded in creating a platform for rural people, including marginalised groups, to be effectively involved in their development. Dysselsdorp was used as a case study in a qualitative approach in order to get an understanding of the experience, views and perceptions of stakeholders, particularly residents and government officials. Data was collected through qualitative research. In-depth interviews were held with relevant government officials, local leaders and ordinary residents and focus groups were held with residents, including local leaders. The research revealed that the involvement of residents in CRDP was limited to needs identification through information giving while needs prioritisation and decisions on implementation were done by government officials. Further, the research suggests that members of the local elite (those who had political connections and social status) captured most of the benefits (i.e. tenders and jobs). Therefore, CRDP in Dysselsdorp had failed to ensure that residents, especially the marginalised, participate fully in their own development. Instead, the status quo remains, where government officials and the elites as representatives of the people make decisions. This corresponds with mere tokenism, as illustrated in Arnstein’s Ladder of Participation Model. A number of factors contributed to the failure to ensure genuine stakeholder participation, including unrealistic expectations of job creation, the assumption of ‘collectivism’, political dynamics in the area and poor institutional design

The Independence of South African Judges: A Constitutional and Legislative Perspective

Judicial independence is fundamental to democracy. It is in that context that this paper considers whether the existing constitutional and legislative mechanisms provide sufficient judicial independence to South African judges. In so doing, the paper focuses on impartiality, judicial appointments and security of tenure. It also discusses the sensitive matter of complaints and disciplinary proceedings against judges and their removal from office. The issue of the remuneration of judges is also explored. In discussing the challenges facing judicial independence some incidents that have appeared to compromise such independence are highlighted. These include the controversial appointments of Advocate Mpshe as an acting judge in the North West Province in 2010 and Judge Heath as the Head of the Special Investigative Unit (SIU) in 2011. The never-ending controversy surrounding the Cape Judge President John Hlophe and his alleged attempts to improperly influence two Constitutional Court judges in a case involving President Jacob Zuma is also highlighted. Another issue that has brought judicial independence into sharp focus is the June 2015 visit to South Africa of Sudan's President Omar al-Bashir, who was on a warrant of arrest from the International Criminal Court (ICC) for genocide and war crimes in the Darfur region of Sudan. A decision by the North Gauteng High Court on his presence in South Africa and the attacks on the judiciary made by various government officials as a result are discussed. Several conclusions are drawn but in the main, it is generally concluded that the constitutional and legislative framework adopted by South Africa sufficiently insulates judges from improper influence. However, there have been several notable challenges that particularly relate to judicial appointments and how the JSC has handled certain matters. Irresponsible and uninformed political statements by politicians and unwarranted political attacks on the judiciary by government are also a source of great concern. These challenges could and should be construed as threats to judicial independence, and need to be comprehensively and properly addressed.   

Isolation of phytochemical constituents from hunteria umbellata k. Schum

Hunteria umbellata K. Schum has been reported for the treatment of diabetes in Nigeria. In the present study, the ethanolic extract of dried leaves of Hunteria umbellata K. Schum was investigated for the chemical principles. The isolated pure compounds were characterized by NMR, IR and Mass spectral studies. Ursolic acid (1), oleanolic acid (2) and squalene (3) were the main constituents isolated from the extract

دراسة تأثير ريزين الكومارون على لاصق مطاطي بأساس كلوروبرين

في هذا البحث تم تحضير لاصق مطاطي أساس كلوروبرين (لاصق تماس) ودراسة النسبة المثلى لتحقيق أفضل توافق (compatibility) بين ريزين الكومارون ومطاط الكلوروبرينCR  بهدف الوصول الى أفضل قوة قشر، حيث تم اختيار عدة نسب لريزين الكومارون ودراسة قوة القشر لركيزة مطاط/معدن، وتبين أن أفضل نسبة تحقق أعلى قوة قشر 4.2 N/mm هي 25 Phr، كما أعطت لزوجة 1164 C.P وهذه القيمة هي اللزوجة المناسبة لتطبيق اللاصق بطريقة الدهن بالفرشاة. تم إجراء الاختبارات السابقة باستخدام جهاز الاختبارات الميكانيكية العامة (FRANK) وجهاز اللزوجة   BROOKFIELD

EXPLORING THE ANTIDIABETIC AND ANTIOXIDANT POTENTIAL OF NEPETA ADENOPHYTA HEDGE IN HEPG2 CELLS AND ITS PHYTOCHEMICAL STUDIES

The current study is based on the phytochemical isolation and biological activity evaluation of Nepeta adenophyta Hedge. This plant species is traditionally used for abdominal pain, kidney pain, stomach problems, urine problems, and diarrhea and is examined to control bleeding. Five compounds were isolated using column chromatography over normal silica gel from the ethanolic crude extract of Nepeta adenophyta and their structures were characterized with the help of spectroscopic techniques. In addition, the crude extract was evaluated for its antioxidant and antidiabetic potential in a human hepatoma cell line HepG2 cells and the crude extract showed good activities. The phytochemical isolation studies and the biological activities are conducted for the first time on the study sample

The Cytotoxicity of the Ajoene Analogue BisPMB in WHCO1 Oesophageal Cancer Cells Is Mediated by CHOP/GADD153

Garlic is a food and medicinal plant that has been used in folk medicine since ancient times for its beneficial health effects, which include protection against cancer. Crushed garlic cloves contain an array of small sulfur-rich compounds such as ajoene. Ajoene is able to interfere with biological processes and is cytotoxic to cancer cells in the low micromolar range. BisPMB is a synthetic ajoene analogue that has been shown in our laboratory to have superior cytotoxicity to ajoene. In the current study we have performed a DNA microarray analysis of bisPMB-treated WHCO1 oesophageal cancer cells to identify pathways and processes that are affected by bisPMB. The most significantly enriched biological pathways as assessed by gene ontology, KEGG and ingenuity pathway analysis were those involving protein processing in the endoplasmic reticulum (ER) and the unfolded protein response. In support of these pathways, bisPMB was found to inhibit global protein synthesis and lead to increased levels of ubiquitinated proteins. BisPMB also induced alternate splicing of the transcription factor XBP-1; increased the expression of the ER stress sensor GRP78 and induced expression of the ER stress marker CHOP/GADD153. CHOP expression was found to be central to the cytotoxicity of bisPMB as its silencing with siRNA rendered the cells resistant to bisPMB. The MAPK proteins, JNK and ERK1/2 were activated following bisPMB treatment. However JNK activation was not critical in the cytotoxicity of bisPMB, and ERK1/2 activation was found to play a pro-survival role. Overall the ajoene analogue bisPMB appears to induce cytotoxicity in WHCO1 cells by activating the unfolded protein response through CHOP/GADD153.Peer reviewe

Influence of Carbon Supports on Palladium Nanoparticle Activity toward Hydrodeoxygenation and Aerobic Oxidation in Biomass Transformations

[EN] Three palladium catalysts at similar loadings supported on few-layers graphene (FLG), carbon nanotubes (CNT) and carbon nanofibers (CNF) have been prepared by wet impregnation of palladium nitrate with the purpose of determine the influence of the support on Pd catalytic activity. The supports and catalysts have been characterized by chemical analysis, Raman spectroscopy, XRD, electron microscopy and XPS. The average Pd particle size depends on the carbon support, ranging from 1.6 nm for CNF to 2.6 nm for FLG. The catalytic activity of these catalysts was evaluated for two different reactions of interest for biomass transformations, namely hydrodeoxygenation of vanillin to 2-methoxy-4-methyl-phenol (creosol) that requires a bifunctional catalyst with hydrogenating and Lewis acid sites, and aerobic oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid. Both compounds have application either as food flavouring additive and polyester co-monomer. For the two reactions the activity order of the fresh catalyst was Pd/FLG > Pd/CNF > Pd/CNT, indicating that FLG contributes favorably to the activity in spite of the larger Pd size of the nanoparticles on this support, a fact that has been attributed to the interaction with the prismatic planes on where Pd nanoparticles are located.Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa GTQ2015-65163-C02-R1 and CTQ2014-53292-R) is gratefully acknowledged. Generalidad Valenciana is also thanked for funding (Prometeo 2017/063). S. N. thanks financial support by the Fundacion Ramon Areces (XVIII Concurso Nacional para la Adjudicacion de Ayudas a la Investigacion en Ciencias de la Vida y de la Materia, 2016). C. R. C. thanks CONICYT for the financial support (Becas de doctorado en el extranjero "Becas Chile" - no 72170200). 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Molecular mechanisms involved in the anticancer activity of BISPMB in oesophageal cancer cells

BisPMB (E, Z)-1,8-(Bis-p-methoxyphenyl)-2,3,7-trithiaocta-4-ene 7-oxide) is a synthetic analogue of the garlic compound ajoene. It is 12 times more active at inhibiting the growth of oesophageal squamous cell carcinoma WHCO1 cells and displays selectivity for cancer cells over normal cells. BisPMB is therefore attractive as a potential cancer therapeutic. In this study, bisPMB was found to inhibit WHCO1 cancer cell proliferation in a time and concentration dependent manner with 24 hour IC50's between 6.7 - 8.1 μM against a range of oesophageal cancer cell lines including WHCO1, KYSE30 and WHCO6. The normal oesophageal epithelial cell line, HET1A was found to be five times less responsive to bisPMB. Furthermore, bisPMB was found to induce apoptosis and G2/M cell cycle arrest in WHCO1 cells. Gene expression data obtained from the microarray analysis showed that bisPMB primarily targets the unfolded protein response (UPR) in WHCO1 cells. We also found that bisPMB deregulated the ER stress genes involved in protein processing in the endoplasmic reticulum and also deregulated MAPK pathways in WHCO1 cells. At a protein level, bisPMB was found to induce an increase in protein ubiquitination and in the expression of ER stress and UPR genes ATF4, Grp78 and CHOP in WHCO1 cells. We also observed a decrease in ATF6 90 kDa protein and transient XBP-1 mRNA splicing. The activation of p38, JNK and ERK MAPK pathways in bisPMB treated WHCO1 cells was also observed. Furthermore siRNA mediated knock-down of CHOP abolished the anti-proliferative effect of bisPMB in WHCO1 cells. However, inhibition of JNK and p38 MAPK by chemical inhibitors, SP600125 and SB 203580 respectively, had no effect on bisPMB antiproliferative activity against WHCO1 cells. On the other hand, inhibition of ERK1/2 MAPK by U0126 enhanced the anti-proliferative effect of bisPMB in WHCO1 cells. These results support the hypothesis that ER stress and MAPK signalling pathways are essential for bisPMB induced cytotoxicity in oesophageal cancer cells

ANALISIS PENGARUH KUALITAS PELAYANAN RELATIONSHIP MARKETING TERHADAP KEPUASAN KONSUMEN YANG BERDAMPAK PADA LOYALITAS PELANGGAN PT. CAHAYA LESTARI

ANALISIS PENGARUH KUALITAS PELAYANAN RELATIONSHIP MARKETING TERHADAP KEPUASAN KONSUMEN YANG BERDAMPAK PADA LOYALITAS PELANGGAN PT. CAHAYA LESTARI