细化搜索
结果 1-7 的 7
Growth and yield of 15-year plantations of pine, spruce and birch in agricultural land
2017
Daugaviete, M., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdina, D., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Makovskis, K., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Daugavietis, U., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The growth data and the potential returns from 15-year-old plantations of pine Pinus sylvestris L. (6 trial sites), spruce Picea abies Karst L. (9 trial sites) and silver birch Betula pendula Roth (13 trial sites), established in abandoned agricultural lands in a variety of soil types (sod calcareous, anthrosols, podzolic, podzols, gley, podzolic gley, alluvial), using the planting density 2,500 and 3,300 and also 5,000 trees/ha are analysed. For tree plantations in agricultural soils (alluvial sod-gley, gley-sod podzolic, sod-podzolic gley, typic podzol) at the survival of 80-98% the stock volume for 15-year pine is as high as 102-155 m**3haE−1 with the volume growth 5.72-8.94 m**3haE−1 per year; the same indices for spruce in agricultural soils (gley sod-calcareous, sodpodzolic, cultivated, sod-podzolic gley, alluvial sod-gley, base-unsaturated brown) are 75-98 m**3haE−1 and 10.26-15.76 m**3haE−1, respectively. For 15-year plantation birch the mentioned indices may vary from 61 to 169 m**3haE−1 and from 7.54 to 29.82 m**3haE−1 per year. The lowest volume growth (4.66 m**3haE−1 per year) is for birch in heavy clay soil (gleyic sod-podzolic), the highest (29.72-29.82 m**3haE−1 per year) – in cultivated soils and pseudogley soil. Plantation cultivation of pine, spruce and birch in agricultural lands may by the age of 15 years yield with a profit such forest products as pulpwood, fire wood and woody biomass. The gross income gained from first commercial thinnings of plantation pine, utilizing pulpwood, fire wood and logging residue biomass, may vary from 679-2267 EUR haE−1, for spruce the same indices are 1644-3272 EUR haE−1, for birch - 683-2188 EUR haE−1.
显示更多 [+] 显示较少 [-]Potatoes as wheat flour substitute in gluten-free pastry cream
2023
Kince, Tatjana | Zilinska, Elina | Galoburda, Ruta | Tomsone, Lolita | Straumite, Evita | Goldmanis, Juris | Sabovics, Martins
Pastry cream contains wheat flour, which is not suitable for celiac patients who require a gluten-free diet. Potatoes are known as a good source of starch, minerals and vitamins. They also contain protein, dietary fibre and various phytochemicals. Their addition to pastry cream can both serve as a texturizing agent and enrich the nutritional value of the final product. This study aimed to evaluate the suitability of potatoes as a replacement for wheat flour in pastry cream. For study purposes, the physicochemical attributes of eleven potato varieties were evaluated. Among other varieties, the boiled potato variety Gala exhibited higher fibre, fat, phosphorus and potassium content; however, significantly higher protein (12.48 ± 0.08 g 100 gE−1 DW) and iron (3.12 ± 0.02 g 100 gE−1 DW) content. Higher antiradical activity (18.72 ± 0.74 mM TE 100E−1 g DW) was detected in potatoes of the variety Blue Congo. After preliminary investigation, wheat flour was replaced with mashed potatoes, making up 30% of the cream weight, and its impact on the pastry cream was studied. It was established that potatoes had a significant effect on pastry cream colour and texture. American Rose, Imanta, Rigonda and Viviana were selected as the most suitable from the eleven varieties tested. The addition of potatoes in pastry cream doubled its fibre and potassium content, whereas, other changes in nutritional value of the creams were variety dependent.
显示更多 [+] 显示较少 [-]Assessment of maximum cross-sectional area and volume of the canine biceps brachii – brachialis muscles
2018
Veksins, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Kozinda, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The biceps brachii - brachialis muscles has attachment on the medial coronoid process (MCP) and proximal radius. It is considered that medial coronoid disease (MCD) can be caused by biceps brachii – brachialis muscle generated force to MCP. Computed tomography data from 31 dogs were analysed. The aim of this study was to compare biceps brachii – brachialis muscle volume and maximum cross-sectional area (mCSA) between clinically normal dogs to dogs with a MCD. Results showed that in dogs with MCD, biceps brachii - brachialis muscle volume and mCSA is smaller than in clinically normal dogs and therefore the generated muscle force cannot be considered as the main or accompanying cause of a MCD.
显示更多 [+] 显示较少 [-]In vitro testing of lactic acid bacteria from commercial yoghurts
Lakstina, Jana | Ciprovica, Inga | Majore, Kristine
Yoghurt has been known as an excellent source for delivering viable lactic acid bacteria (LAB) in concentrations providing benefits to the human host and microbiome. Different gastrointestinal tract (GIT) simulators have been developed and are successfully used to determine the viability of LAB from fermented dairy products in vitro studies. Commercial yoghurts were tested for digestibility using the GIT IT system Labfors 5 (INFORS HT, Switzerland). The length for both the gastric phase and the small intestinal phase was 120 min each. Yoghurt LAB colony-forming units were analysed prior to the GIT simulation test, as well as after the simulation test. The survival rate of LAB was evaluated based on the differences in the viable LAB count at the beginning and at the end of the experiment. Tested yoghurts’ LAB were tolerated in the simulated gastric and small intestinal phases. Samples collected prior to and after the intestinal phase revealed that LAB had adapted and started to grow within 120 min. Our results showed the ability of LAB to recover in the intestinal phase which has been explained by the food matrix, which protects the bacteria from the elimination effect of intestinal secretions. In addition, differences in survival rates of LAB significantly influenced the overall LAB colony-forming units in the gastrointestial tract. The chemical composition of the product has an influence on the survival rate of LAB, and it should be studied more thoroughly. In vitro studies are quite different from the assay in vivo studies; however, this information provides significant data about the viability of LAB from regularly consumed products and helps to modulate the influence of LAB on human microbiota.
显示更多 [+] 显示较少 [-]Sensory and textural properties of frozen muffins prepared with cottage cheese and tofu
Klava, Dace | Straumite, Evita | Jansone, Liene | Sedmalis, Andris
Muffin is a flour confectionery product with an elastic texture. Nowadays, vegetable products are replacing traditional dairy products more often in the food sector. Tofu, which is a quintessential soy protein product, is one of the alternatives for making vegan products. The aim of this research was to determine the influence of defrosting processes to changes of sensory and textural properties of muffins with cottage cheese and its vegan substitutes. Five types of muffins were used in the study – muffin without cottage cheese (control), muffin with cottage cheese, muffin with lactose-free cottage cheese, tofu muffin and tofu chickpea muffin, which were thawed after freezing in two ways (at room temperature and in a microwave oven). For the determination of muffin quality, the Quantitative descriptive method (QDA) was used, and for overall liking, the 7-point hedonic scale and acceptance – Just-about-Right (JAR) method were used. To evaluate physical-chemical and textural analysis, standard methods were used. The method of defrosting muffins – room (ambient) temperature or microwave – has no significant effect (p is greater than 0.05) on the quality and JAR rating of the muffins with cottage cheese and tofu. The obtained results showed that the addition of plant-based protein sources significantly reduces the volume of muffins; the texture of the muffins becomes softer, but stickier. In the process of defrosting using a microwave, the structure of the muffins is drier, softer, whitish, and less sticky, compared to a muffin thawed at 22 °C.
显示更多 [+] 显示较少 [-]Total soluble sugars in root and stem of Wichita and Western Carya illinoinensis varieties in northern Mexico
Concilco-Alberto, Ernesto | Valenzuela-Núñez, Luis Manuel | González-Torres, Anselmo | La Peña, Cristina García-De | Briceño-Contreras, Edwin Amir | Rivera, Juan Ramon Esparza | Reyes-Carrillo, José Luis | García-Carrillo, Mario
The aim of the current study was to determine the monthly total soluble sugar concentration in the stem and root of the Wichita and Western walnut (Carya illinoinensis) varieties during a productive cycle in northern Mexico. Vegetable samples were obtained using a systematic sampling method, and processed by means of a spectrophotometric assay to determine the total soluble sugars (TSS) concentration in productive walnut trees. Data analysis was performed by means of a 2-way ANOVA. The results of the TSS concentration had differences throughout the months of an annual productive cycle, and were also different between the evaluated walnut varieties. The highest total soluble sugar concentration in stem and root were in the lowest temperature months, and it decreases in both tissues when the environmental temperature rises. The Wichita variety had a higher total soluble sugar concentration than the Western in every month during the productive cycle. Further research is required to assess the effect of other type of factors including environmental or agronomic over the dynamics of the total soluble sugars in productive walnut trees.
显示更多 [+] 显示较少 [-]Bumblebee pollination activity in a commercial tomato greenhouse during the winter season
2022
Ozols, Niks | GailisGailis, Jānis, Janis | Jakobija, Inta | JaskoJaško, Jānis, Janis | Zagorska, Viktorija
Bumblebee activity interaction with solar irradiation, solar irradiation and HPS lighting irradiation, the HPS effect of photoperiod, day temperature and hive density were assessed with tomato fruit weights in a commercial tomato glass greenhouse in 2020–2021. Pollination activity was measured by observing ten randomly chosen cv. ‘Be orange’ tomato plants and by counting bumblebee bruised tomato flowers. MANOVA was conducted between factors and bee activity, followed by Pearson’s correlation. A Mann-Whitney U test was calculated to determine the significance between tomato flower bruising levels and fruit weights, followed by Cliff’s delta (d). Pollination activity decreased mainly in December and January when solar irradiation decreased to below 110 J cmE−2 dayE−1. Bumblebee activity was significantly affected by solar irradiation with HPS lighting (p is less than 0.001; p is less than 0.01). There was a significant correlation between bumblebee activity and solar irradiation (r= 0.75; p is less than 0.05), and solar irradiation with HPS lighting (r= 0.70; p is less than 0.05). There was no correlation between bumblebee activity and fruit weights (r= −0.20; p is less than 0.05). Bruised flowers had significantly greater fruit weight increases (165.7 g) compared to unbruised flowers (123.4 g) (d= 0.12; p is less than 0.05). Bee activity rates between 60% and 80% can be concluded as an effective rate for tomato growers. Bumblebees need at least 110–154 J cmE−2 dayE−1 of solar irradiation to achieve a high pollination activity rate in temperate climate zones during the winter season.
显示更多 [+] 显示较少 [-]