Secondary Industries for Tropical Africa

Africa ◽  
1943 ◽  
Vol 14 (4) ◽  
pp. 170-176 ◽  
Author(s):  
Theresa Cahan

Opening ParagraphThere is a tendency in some quarters to regard secondary industries as a panacea for all the economic ills of tropical Africa. It would be well at this initial stage to sound a note of warning. In the past, the industrialization of agricultural countries has had two results: one good, one bad. On the one hand, the establishment in a country of labour-saving machinery and large-scale production in place of the old laborious method of making things by hand has led to a rise in the general standard of living within the country in terms of real incomes. On the other hand, the drift of workers to the towns and the herding together of large numbers of people in factories resulted in the sum of social evils associated with the ‘dark satanic mills’: overcrowding, sweated labour, destitution, unemployment, and many more. The problem for tropical Africa to-day is to combine the maximum of the first and good effect with a minimum of the second evil.

Author(s):  
Allan John ◽  
Bill Mason

SynopsisA combination of two vegetative techniques is seen as a possibility for large-scale production of juvenile, rooted Sitka spruce cuttings of improved genotype. Tissue culture techniques, under development, would be used to produce large numbers of stock plants for stem cuttings production. Cuttings techniques, currently under commercial trial, would be used to produce the rooted plants for forest establishment.


2015 ◽  
Vol 719-720 ◽  
pp. 123-126
Author(s):  
Jin Sun ◽  
Qing Zhong Xue ◽  
Yong Gang Du ◽  
Fu Jun Xia ◽  
Qi Kai Guo

Porous graphene is a collection of graphene-related materials which exhibits properties distinct from those of graphene, and it has widespread potential applications in various fields. Several approaches have been developed to produce porous graphene. However, the large-scale production of porous graphene nanosheets still remains a great challenge. Moreover, the costs of some methods are prohibitive for its commercial production and the processes are too complicated and time-consuming. In this work, we propose a simple and green method by which graphene nanosheets can be etched by sodium hydroxide under autogenous pressure at 180 °C. The morphologies and surface elements of the porous graphene nanosheets and sizes of pores were characterized. It is demonstrated that the one-step etching of graphene nanosheets is an effective method to obtain large-scale porous graphene nanosheets with high and uniform porosity. The pores in the porous graphene nanosheets were 6 nm depth (the same as the thickness of the graphene nanosheets) and 30-50 nm width.


2017 ◽  
Vol 171 (4) ◽  
pp. 250-254
Author(s):  
Włodzimierz STAWECKI ◽  
Maciej BAJERLEIN ◽  
Paweł DASZKIEWICZ

The article presents an overview of modern steel used in rail transport. Directions for the development of materials, technologies and constructions used in the manufacture of rail vehicles are, on the one hand, determined by the technical and economic requirements of industry and, on the other, by the continued emphasis of environmentalists on reducing fuel consumption and CO2 emissions. This generates innovation in the use of modern materials, processing methods and new design solutions and results in reduced vehicle weight. More bold forecasts today show that at the current pace of technology development, in the near future the mass of the vehicle will reduce by an average of 30%. Observing the trends and pace of rail transport development, it can be predicted that existing restrictions on the use of modern materials, such as high prices, technological conditions and difficult automation of large-scale production, can be predicted.


1948 ◽  
Vol 26d (1) ◽  
pp. 8-25 ◽  
Author(s):  
A. Wilkes ◽  
G. E. Bucher ◽  
J. W. MacB. Cameron ◽  
A. S. West Jr.

Using the Peet-Grady method for propagating houseflies required as biological test animals, variations were observed that had considerable bearing on production and subsequent adult life. Differences in length of life, fecundity, time of emergence of the adults from puparia, and the onset of egg laying occurred between different populations of flies. Investigations were carried out to determine the extent and causes of the variations and to develop more suitable techniques for producing large numbers on a more accurately predictable basis. Variability in production of puparia was found to be due largely to the age of female stock and rate of fermentation in the rearing medium through their effects on egg hatchability and larval survival and excessive crowding caused by high temperatures. By using eggs from genetically-selected stock of known age and rearing in a temperature-controlled medium, production of flies was increased and maintained at a constantly uniform rate. A description is given of the equipment and methods used.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Bianca Ferrarini Zanetti ◽  
Walter José Gomes ◽  
Sang Won Han

The large-scale production of cardiomyocytes is a key step in the development of cell therapy and tissue engineering to treat cardiovascular diseases, particularly those caused by ischemia. The main objective of this study was to establish a procedure for the efficient production of cardiomyocytes by reprogramming mesenchymal stem cells from adipose tissue. First, lentiviral vectors expressing neoR and GFP under the control of promoters expressed specifically during cardiomyogenesis were constructed to monitor cell reprogramming into precardiomyocytes and to select cells for amplification and characterization. Cellular reprogramming was performed using 5′-azacytidine followed by electroporation with plasmid pOKS2a, which expressed Oct4, Sox2, and Klf4. Under these conditions, GFP expression began only after transfection with pOKS2a, and less than 0.015% of cells were GFP+. These GFP+cells were selected for G418 resistance to find molecular markers of cardiomyocytes by RT-PCR and immunocytochemistry. Both genetic and protein markers of cardiomyocytes were present in the selected cells, with some variations among them. Cell doubling time did not change after selection. Together, these results indicate that enrichment with vectors expressing GFP and neoR under cardiomyocyte-specific promoters can produce large numbers of cardiomyocyte precursors (CMPs), which can then be differentiated terminally for cell therapy and tissue engineering.


2021 ◽  
Author(s):  
Dimitra Makarouni ◽  
Christos Kordulis ◽  
Vassilis Dourtoglou

AbstractApplication of a novel “zeolite catalyst–solvent” system for the sustainable one-step synthesis of the terpenoid manoyl oxide, the potential precursor of forskolin and ambrox. Manoyl oxide high-yield and large-scale production over a zeolite catalyst has been infeasible so far, while this system results in 90% yields at 135 °C and atmospheric pressure. Substrate-controlled methodology is used to achieve selectivity. Solvent-driven catalysis is shown, as the activation energy barrier decreases in the presence of appropriate solvents, being 62.7 and 93.46 kJmol−1 for a glyme-type solvent and dodecane, respectively. Finally, catalyst acidity is key parameter for the process. Graphic Abstract


1993 ◽  
Vol 32 (1) ◽  
pp. 129-131
Author(s):  
Naureen Talha

The literature on female labour in Third World countries has become quite extensive. India, being comparatively more advanced industrially, and in view of its size and population, presents a pictures of multiplicity of problems which face the female labour market. However, the author has also included Mexico in this analytical study. It is interesting to see the characteristics of developing industrialisation in two different societies: the Indian society, which is conservative, and the Mexican society, which is progressive. In the first chapter of the book, the author explains that he is not concerned with the process of industrialisation and female labour employed at different levels of work, but that he is interested in forms of production and women's employment in large-scale production, petty commodity production, marginal small production, and self-employment in the informal sector. It is only by analysis of these forms that the picture of females having a lower status is understood in its social and political setting.


2018 ◽  
Vol 15 (4) ◽  
pp. 572-575 ◽  
Author(s):  
Ponnusamy Kannan ◽  
Samuel I.D. Presley ◽  
Pallikondaperumal Shanmugasundaram ◽  
Nagapillai Prakash ◽  
Deivanayagam Easwaramoorthy

Aim and Objective: Itopride is a prokinetic agent used for treating conditions like non-ulcer dyspepsia. Itopride is administered as its hydrochloride salt. Trimethobenzamide is used for treating nausea and vomiting and administered as its hydrochloride salt. The aim is to develop a novel and environmental friendly method for large-scale production of itopride and trimethobenzamide. Materials and Methods: Itopride and trimethobenzamide can be prepared from a common intermediate 4- (dimethylaminoethoxy) benzyl amine. The intermediate is prepared from one pot synthesis using Phyrdroxybenzaldehye and zinc dust and further reaction of the intermediate with substituted methoxy benzoic acid along with boric acid and PEG gives itopride and trimethobenzamide. Results: The intermediate 4-(dimethylaminoethoxy) benzylamine is prepared by treating p-hydroxybenzaldehyde and 2-dimethylaminoethyl chloride. The aldehyde formed is treated with hydroxylamine hydrochloride. The intermediate is confirmed by NMR and the purity is analysed by HPLC. Conclusion: Both itopride and trimethobenzamide were successfully synthesized by this method. The developed method is environmental friendly, economical for large-scale production with good yield and purity.


Marine Drugs ◽  
2021 ◽  
Vol 19 (5) ◽  
pp. 241
Author(s):  
Shaden A. M. Khalifa ◽  
Eslam S. Shedid ◽  
Essa M. Saied ◽  
Amir Reza Jassbi ◽  
Fatemeh H. Jamebozorgi ◽  
...  

Cyanobacteria are photosynthetic prokaryotic organisms which represent a significant source of novel, bioactive, secondary metabolites, and they are also considered an abundant source of bioactive compounds/drugs, such as dolastatin, cryptophycin 1, curacin toyocamycin, phytoalexin, cyanovirin-N and phycocyanin. Some of these compounds have displayed promising results in successful Phase I, II, III and IV clinical trials. Additionally, the cyanobacterial compounds applied to medical research have demonstrated an exciting future with great potential to be developed into new medicines. Most of these compounds have exhibited strong pharmacological activities, including neurotoxicity, cytotoxicity and antiviral activity against HCMV, HSV-1, HHV-6 and HIV-1, so these metabolites could be promising candidates for COVID-19 treatment. Therefore, the effective large-scale production of natural marine products through synthesis is important for resolving the existing issues associated with chemical isolation, including small yields, and may be necessary to better investigate their biological activities. Herein, we highlight the total synthesized and stereochemical determinations of the cyanobacterial bioactive compounds. Furthermore, this review primarily focuses on the biotechnological applications of cyanobacteria, including applications as cosmetics, food supplements, and the nanobiotechnological applications of cyanobacterial bioactive compounds in potential medicinal applications for various human diseases are discussed.


Sign in / Sign up

Export Citation Format

Share Document