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Planned development and transfer of technology [Philippines]
1981
Woods, J.L.
The educational and cultural dimensions in integrated rural development: the IIRR [International Institute of Rural Reconstruction, Silang, Cavite, Philippines] experience
1981
Cabacungan, D.P.
Community organization approach to extension work [in the Philippines]
1981
Isles, C.D.
Prospects of modular instructional technology for an effective extension delivery system [in the Philippines]
1981
Nordland, F.H.
Organizational constraints to implementing [rural] development projects
1981
Woods, J.L.
Use of automatically obtained data in the quantitative and qualitative evaluation of harvester operator training
2024
Strubergs, Aigars | Sisenis, Linards | Sarmulis, Ziedonis
The study aims to find out the efficiency of periodic training of the harvester (cut-to-length) operator, using the automatically saved data of the harvesterʼs information system. It has been established that logging service providers and training institutions do not analyse the operatorʼs work before starting the training; therefore, the training is carried out according to certain, standard programs, without going into the previous performance of each trainee operator. The research uses data automatically saved by Ponsse harvesters during the year, obtained from Ponsse Manager. The study found that by using automatically saved data of the harvester information and performing data grouping with subsequent analysis, it is possible to determine the progress in the execution of specific stem processing operations and to identify operations where the instructor should pay increased attention during training. The research analysed the data of 3 operators, obtained while working with Ponsse harvesters in clear-cutting. In the study, it was found that operator A reduced stem processing time by 3%, labour productivity increased by 15%, and fuel consumption per l m⁻³ decreased by 14% over 3 months. Operator B, after training, saw a 20% reduction in stem processing time, a 13% increase in work productivity, and a 5% increase in fuel consumption l m⁻³ over 3 months. Operator C had a 10% increase in stem processing time, a 1% increase in labour productivity, and a 2% increase in fuel consumption l m³ after training.
Afficher plus [+] Moins [-]The composition and richness of ground cover vegetation in drained forest stand
2024
Liepina, Agnese Anta | Jansone, Diāna | Samariks, Valters | Jansons, Āris
Forest drainage is a common management practice, carried out in order to improve tree growth; however, the alterations in hydrological and microclimate dynamics can cause diverse changes in the characteristics of ground cover vegetation. The aim of study was to characterise the composition and richness of ground cover vegetation in drained forest stands, where the groundwater levels have been affected by the reconstruction of drainage diches. Research was conducted in the hemiboreal forests of Latvia. Three study sites were chosen, measurements of groundwater level, stand parameters and projective cover of ground covered vegetation took place in two stands which underwent reconstruction and restoration of the drainage system in 2019, and a control stand, where the drainage system had not been restored. For assessing the relationship of ground cover vegetation in relation to groundwater level and stand factors, DCA analysis was used. The differences between stands, regarding the species projective cover and species composition, were assessed by ANOSIM (Analysis of similarities). Sites, where drainage ditches were fully or partially reconstructed exhibited a greater diversity of ground cover vegetation species compared to the control stand, where no renewal of drainage ditches had occurred. Conversely, the control stand displayed a higher projective cover of the bryophyte layer. The composition of ground cover vegetation species differed amongst all studied stands, the varying stand characteristics and co-dominant tree species in canopy layer had a more pronounced influence on ground cover vegetation, making it complicated to evaluate direct impact of groundwater level.
Afficher plus [+] Moins [-]Rosemary essential oil by hydrodistillation: SPME-GC-MS characterization
2024
Calvo-Gomez, Octavio | Ruzibayev, Akbarali | Akramova, Rano | Salijonova, Shakhnozakhon | Gaipova, Shakhnozakhon | Khodjaev, Sarvar
Rosemary (Salvia rosmarinus) is an aromatic herb with a multitude of uses. It is both a seasoning in various dishes, and a natural remedy for several diseases mainly due to its anti-inflammatory and anti-oxidative effects. Plus, it is also used in cosmetic industry and for improving agriculture practices and helping the environment, since it may be a natural antimicrobial. It is worth noting that this plant is also grown and commercialized in Uzbekistan, thus, if added value is given to rosemary’s products, it has potential for improving living conditions and helping in the economy of local farmers and entrepreneurs. In this work, we discuss a technique for obtaining rosemary essential oil, rich in terpenes, by vacuum assisted hydrodistillation. This is a solventless environmentally friendly and safe technique that allows the obtention of an added value rosemary product where terpenes, compounds responsible for most of rosemary’s properties, are the most abundant. Two samples of locally acquired rosemary were sourced, essential oil was extracted, and characterization was then performed by Solid Phase Micro Extraction (SPME) and Gas Chromatography – Mass Spectrometry (GC-MS). As a comparison, a direct injection of a dilution of one of the essential oil samples was also performed. It was concluded that samples of essential oil obtained from both sources were entirely composed of terpenes or terpene derivatives. Besides, SPME was a superior method when compared to direct injection, since a larger number of volatiles was able to be identified.
Afficher plus [+] Moins [-]Chemometrics as an aid to quickly evaluate galactomannans through infrared spectroscopy
2024
Calvo-Gomez, Octavio | Ruzibayev, Akbarali | Salijonova, Shakhnozakhon | Gaipova, Shakhnozakhon | Khodjaev, Sarvar | Khakimova, Zulfiyakhon | Rakhimov, Dilshod
Galactomannans, composed of galactose and mannose, may form gels and are considered safe because of their non-toxic, biodegradable, and biocompatible nature. As a result, they are widely utilized in the food industry as stabilizers and thickeners. Among galactomannan producing species, guar gum and locust bean gum are particularly important due to their economical relevance. Guar gum and locust bean gum are often adulterated with cellulose gums like xanthan gum and carboxymethyl cellulose (CMC). Adulteration of galactomannans with other gums may introduce uncertainties regarding functionality and complicate quality control, posing a potential problem for the food industry. Among the different techniques which have been used for determining and characterizing galactomannans, Fourier Transform Infrared Spectroscopy stands out. Especially when coupled to Attenuated Total Reflection (ATR), analyses are performed rapidly, with a minimum sample preparation, and without the need for solvent or previous extraction mechanisms. However, food is a very complex matrix that contains a high number of components which generate a multitude of spectral information and large data sets. Consequently, additional data processing tools such as chemometrics are needed to be able to draw useful information from spectra. Our goal in this work is to show how to optimize conditions for instrumental analysis by infrared spectroscopy of galactomannans and its constituent monomers and create a chemometric model where galactomannans could be differentiated as a single group. We successfully optimized the PCA model obtained after chemometric processing of infrared data through reducing dimensions by loadings selection.
Afficher plus [+] Moins [-]Identification of the trace and toxic elements of wheat cultivated in different regions of Uzbekistan
2024
Djaxangirova, Gulnoza | Kurbanova, Nodira | Kurbanov, Bakhtiyor
In Uzbekistan, the main food product is bread, which is produced in various forms from local and imported wheat. Most of it is not studied by microelement analysis. The objective of this study is to quantify trace elements in locally produced wheat from various cultivated regions of Uzbekistan. Four different varieties of wheat are cultivated in Sirdarya, Tashkent region, Kashkadarya and Fergana were selected for analysis. Next, a comparative analysis of the elemental composition like iron, zinc, potassium, calcium etc., in the selected samples were studied. To carry out the above aims, an innovative research method was chosen, which is called improved instrumental neutron activation analysis. This method differs from others in its high accuracy in determining trace elements and its multi-element nature. Using this method, we can understand how insufficient nutrients are in baked goods made from wheat grain grown in Uzbekistan. Based on the results of the study, it can be recommended to enrich the soil with fertilizers high in iron and zinc. As a result, in turn, will have a positive effect on the health of the population, since today there is a shortage of the above listed elements. It was also revealed that the concentration of potassium and calcium in wheat cultivated in Uzbekistan is in a high state than other elements. Using the chosen method, two toxic elements were determined and according to the analysis for toxic elements, all four samples are recommended for consumption, as they do not exceed the permissible level for food safety.
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