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Abstract

The development of ecologically adaptable fodder crop varieties is of increasing importance, particularly in the context of climate change. New varieties should be phenotypically and ecologically plastic and able to adapt to differing climactic and soil conditions, ensuring high yields and persistence. Combining Festuca and Lolium species and the development of hybrid (Festulolium) cultivars can be a promising method of combining high yield, high feed quality, persistence, as well as cold, frost and drought tolerance. Breeders at the Institute of Agriculture of Latvia University of Life Sciences and Technologies have been utilizing Festulolium germplasm for several decades. Currently, in cooperation with the molecular genetics laboratory and Latvian gene bank at the Latvian State Forest Research Institute “Silava”, analysis of Festuca, Lolium and their hybrids with DNA markers has been initiated, in order to gain additional knowledge about the breeding material and to increase the efficiency of the breeding process. Results of the assessment of morphological and agronomic traits in long-term field trials are combined with DNA markers analyses in order to determine the correlation of genetic and phenotypic traits.

Abstract

The temperature dependence of unit cell parameters was studied using high-temperature X-ray diffraction and the coefficient of thermal expansion of SnSe single crystal was determined. Fluorescence spectra of SnSe single crystal grown by the Bridgman-Stockbarger method were examined using a Cary Eclipse spectrophotometer at room temperature in the wavelength range 200–900 nm. When the samples were irradiated by a pulse at a wavelength of 230 nm, the fluorescence spectra exhibited maxima at wavelengths 313.07, 423.03, 458.93, 495.07, and 530.00 nm.

Abstract

Jānis Olģerts Ērenpreiss (1929–1996) was a prominent Latvian cancer researcher and theoretician. Starting out as a student, he contributed to the embryonal theory of cancer, experimentally proving the differentiation and regenerative normalisation capabilities of tumour cells. His theoretical work, presented in its most complete form in his final monograph Current Concepts of Malignant Growth (Zinātne Publ., Rīga, 1993), postulates that oncogenes are abnormally activated genes that are involved in gametogenesis and embryogenesis, and that carcinogenesis and senescence are mutually linked processes arising when the cell is exposed to stressful conditions. This article demonstrates how advancements in cancer research over the last decade have confirmed these core concepts, which were far ahead of their time, and how J. O. Ērenpreiss’ legacy continues both under the guidance of the author and in foreign laboratories, expanding understanding of the nature of malignant tumours and the perspectives of cancer treatment.

Abstract

In this paper, we study the limit distribution functions of the (lower-lower), (upper-upper) and (lower-upper) extreme and central-central m-generalised order statistics (m–GOS) of stationary Gaussian sequences under an equi-correlated set up, when the random sample size is assumed to converge weakly and independent of the basic variables. Moreover, sufficient conditions for a weak convergence of generalised quasi-range with random indices are obtained.

Abstract

The article is dedicated to morphological analysis of the Jerusalem artichoke genetic resources collected at the N. I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR). The crop has a wide range of various usages, such as: food and feed, and medicinal, melliferous, and ornamental products. In this study, morphological characteristics of vegetative and generative plant organs (stems, leaves, tubers and inflorescences) from the VIR collections in the Maikop Experiment Station of VIR (Russian Caucasus, Republic of Adygea) and in Gatchina District, Leningrad Province, Russia were analysed. The widest range of variability was observed in accessions from Western Europe. Accessions from United States, Japan and Australia were the most unique in their set of traits, which may indicate specific paths of their evolution in these isolated territories. Accessions with unique combinations of studied traits were determined. Some traits characterizing leaf, inflorescence and tuber proved to be valuable for taxonomic and geographic analyses.

Abstract

Electron transfer chains of plant organelles (both chloroplasts and mitochondria) contain their own special set of ferredoxins. The relatively recently described adrenodoxin-like [2Fe-2S]-ferredoxins MFDX1 and MFDX2 of plant mitochondria are among the least studied of these. Until now, the only established function for them is participation in the final stage of biotin biosynthesis. In this work, using genetic and biochemical approaches, we searched for possible partners of these proteins in the genomes and proteomes of tobacco (Nicotiana tabacum L.) and foxglove (Digitalis purpurea L.) plants. MORF9 protein, one of the auxiliary components of the RNA editing complex of organelles (editosome), was found among the most prominent protein partners of adrenodoxin-like [2Fe-2S] tobacco ferredoxins. According to the results obtained from the yeast two-hybrid system, NtMFDX1 and NtMFDX2 of tobacco also bind and interact productively with the previously uncharacterised long non-coding polyadenylated RNA, which, based on its structural features, is capable of regulating the function of a number of components of complexes I (Nad1, Nad5) and III (protein of the cytochrome c synthesis system CcmF) and contributes to the formation of Fe/S-clusters in the corresponding protein complexes of the respiratory chain of plant mitochondria. We found one of the main components of the thiazol synthase complex (mitochondrial protein DpTHI1) to be the partner of ferredoxin DpMFDX2 of Digitalis purpurea. Finally, additional arguments were obtained in favour of the possible participation of MFDX1 and MFDX2 in the very ancient, but only recently described ‘progesterone’ steroid hormonal regulatory system: in leaves of the previously constructed CYP11A1-transgenic tomato plants, only the mature form of mitochondrial cytochrome P450scc (CYP11A1) of mammals is able to enter the mitochondria, where the above-mentioned components of the electron transport chain are localised. In summary, all of the newly revealed interactions of adrenodoxin-like [2Fe-2S] ferredoxins MFDX1 and MFDX2 indicate their participation in a wide range of functions in plant mitochondria.

Abstract

The aim of the retrospective case-control study was to determine if the health-related quality of life of overweight and obese children is lower than for children with optimal weight, using the KIDSCREEN-52 survey of health-related quality of life. The study examined differences in health-related quality of life assessments between children with optimal weight, and obese and over-weight children, as well as evaluated parental assessments of the quality of life of their children. In total, 200 children aged 8 to 18 years and their parents participated in the study. The results of the study showed that the total quality of life of obese (p < 0.0001) and overweight (p = 0.008) children was lower than for children with optimum weight (p = 0.001). Also, the assessments of quality of life between parents of obese (p < 0.0001) and overweight (p = 0.001) children scored lower than those of parents whose children had optimal weight.

Abstract

Our aim was to estimate the presence of B19V infection markers, the level of cytokines and time period since the appearance of infection in association with ME/CFS clinical symptoms. In 200 ME/CFS patients and 104 control group individuals the presence of B19V-specific IgG/IgM class antibodies, B19V NS1 gene sequence, mRNA expression, viral load and level of cytokines were determined. B19V-specific IgG-antibodies were found in 70% of ME/CFS patients and 67.4% of controls, IgM-antibodies in 8% of patients and in none of controls, B19V genomic sequences in 29% of patients and 3.8% of controls. 58.6% of positive patients had active and 41.4% had latent/persistent B19V infection. B19V NS1 gene expression was detected in 43% of patients. B19V load varied from < 0.2 copies to median 38.2 copies/µg of DNA. According to the antibody pattern, 36% of patients had a recent, and 43% had sustained B19V infection. Patients with the B19V genomic sequence and NS1 specific antibodies significantly more often had lymphadenopathy and multi-joint pain. Onset of the symptoms corresponded to time of appearance of B19V infection. IL-10 and TNF-levels were higher in patients with elevated B19V load. B19V genome 1 was identified in Latvian ME/CFS patients. The results indicated that at least in some cases B19V infection plays an important role in ME/CFS development

Abstract

Due to an ageing population, the necessity for hip replacement has grown, and therefore, new options are being sought, such as the Fast-track principle, to improve patient condition, reduce their hospital stay and enhance the hospital’s ability to treat more patients. The aim of this study was to investigate the effects of same-day patient mobilisation on pain, side effects, complications, duration of hospital stay, and recovery after primary hip replacement, using intermediate-acting local anaesthetics in spinal anaesthesia (SA). A prospective, randomised study was conducted at the Hospital of Traumatology and Orthopaedics. Forty-six patients undergoing total hip replacement were selected and divided into two groups. Spinal anaesthesia was performed in study group (P) with 70 mg plain prilocaine. The control group (B) received 18 mg heavy bupivacaine in SA. On the first postoperative day, pain during movement was 2.00 (P) and 3.33 (B) on the Numeric Pain Rating Scale, the duration of hospital stay in the study group was shorter by ~1 day, and patient self-care was better in the study group. When the Fast-track principle is used with intermediate-acting SA and early rehabilitation, it is possible to reduce post-operative pain during movement, reduce the length of stay and improve patient self-care abilities.

Abstract

Patients with peripheral arterial disease (PAD) have substantially impaired health-related quality of life (HR-QoL). Chronic lower limb ischaemia due to the atherosclerotic occlusion of infra-inguinal arteries is one of the most important causes of invalidity among smokers over the age of fifty. Historically, these lesions were treated by open bypass surgery. Less invasive endovascular revascularisation methods are available to treat short lesions, while treatment of long lesions are lacking. Fully endovascular trans-venous femoro-popliteal bypass (PQ Bypass, Inc., Sunnyvale, CA, USA) to treat long femoral lesions has been developed recently. The objective of the study was to evaluate duplex ultrasound (DUS) as a tool to follow up patients after PQ bypass procedure. A prospective clinical study was conducted at one clinical site. DUS of treated arteries and femoral vein was performed before the procedure, 30 days, 6 months, and 12 months in follow-up period by 2 independent radiologists. Ankle-brachial index (ABI) evaluation was performed at all visits. Thirty-five patients (35 limbs) treated with PQ bypass were enrolled in the study. Median age was 63.6 years (ranged 50 to 87 years). There was 100% successful evaluation of all patients at all clinical visits available. Deviation of the DUS results was found within the accepted standard limit between two radiologists. Twelve months after the PQ procedure, 28 (80.0%) PQ stent-grafts were still functioning without DUS signs of stenosis, while seven (20.0%) limbs experienced varying degrees of stent malfunction. PQ stent-graft occlusion was detected in five (14.3%) – 1 (2.9%) patients at one-month follow-up, 3 (8.6%) at six months and 1 (2.9%) at twelve months follow-up period, respectively. PQ stent-graft proximal junction stenosis was detected in one patient (2.9%) at six months and distal junction stenosis in one patient (2.9%) at twelve months follow-up, respectively. Despite of graft occlusion found with DUS, two patients had no severe worsening of post-operative ABI. DUS is a reliable method to evaluate patients after PQ bypass procedure and has higher sensitivity than ABI to follow-up patients after PQ procedure, especially in asymptomatic stent stenosis. Regular and timely use of DUS during the postoperative period may help to recognise potential complications and provide effective treatment..