Search Results (57)

Objectives: Although bluetongue is not a contagious disease, it is easily transmitted and spread by appropriate insect vectors, causing great economic damage. Climate change has led to the fact that vectors and diseases have spread to the top of Northern Europe, causing great economic losses in livestock production. An even greater problem is controlling the disease, because numerous species of domestic and wild ruminants are susceptible to bluetongue. The most effective tool against bluetongue disease is vaccination. Methods: Our goal was to carry out laboratory tests of the starting material and the finished product of the candidate inactivated vaccine against BTV4, and to comment on the obtained laboratory results and the results of previously performed clinical studies. There is no ideal vaccine against the bluetongue virus (BTV) due to the serotype diversity of its strains. Thus, there is a need for a vaccine for at least 24 clinically significant serotypes. Sometimes, it is difficult to obtain the desired amount of vaccine against a defined serotype on the market, and this has led to the need for a new vaccine against bluetongue disease. In this study, we tested an experimental inactivated vaccine against BTV4. The master seed BTV4 was examined and characterized by sequencing. Results: The candidate BTV4 vaccine induced the onset of immunity at the latest at day 21 after the application of the first dose in more than 80% of the vaccinated individuals, while the ELISA test detected specific antibodies against BTV for more than a year. Along with our laboratory results, the preliminary results of safety and efficacy trials are also presented. Conclusions: The side effects of this inactivated BTV4 vaccine are within the limits of permissible local reactions without generalized changes in the health status, while the serology and challenge test leads to the conclusion that this vaccine against BTV4 protects a high percentage of vaccinated individuals against BTV4 or causes a significant reduction in the intensity and duration of the clinical signs in the vaccinated sheep. Based on the trial results, the new vaccine has given encouraging results in terms of quality, safety, and preliminary efficacy tests. Thus, we believe that a new vaccine against BTV is on the horizon. Full article

Peste des petits ruminants virus (PPRV), which is the only member of the Morbillivirus caprinae species and belongs to the genus Morbillivirus within the Paramyxoviridae family, causes the highly contagious viral sickness “Peste des petits ruminants (PPR).” PPR is of serious economic significance for small ruminant production, particularly in Africa. Control of this critical disease depends highly on successful vaccination against the PPRV. An in-depth understanding of the genetic evolution of the live-attenuated PPR vaccine Nigeria 75/1 strain used in Africa is essential for the successful eradication of this disease by 2030. Therefore, this study investigated the possible genetic evolution of the PPR vaccine produced by various African laboratories compared with the master seed available at AU-PANVAC. RT-PCR was performed to amplify a segment of the hypervariable C-terminal part of the nucleoprotein (N) from commercial batches of PPR vaccine Nigeria 75/1 strain. The sequences were analyzed, and 100% nucleotide sequence identity was observed between the master seed and vaccines produced. The results of this study indicate the genetic stability of the PPR vaccine from the Nigeria 75/1 strain over decades and that the vaccine production process used by different manufacturers did not contribute to the emergence of mutations in the vaccine strain. Full article

Background. Nurses’ perceptions of health are essential to decision making and communicating with clients. However, little is known about their own perceptions of this phenomenon. This study focuses on health-related beliefs among young nurses enrolled in a master’s-level nursing program using a modified photovoice methodology. Methods. The study population was 87 nurses undergoing a master’s degree in nursing at Jagiellonian University Medical College in Krakow, Poland, participating in an obligatory health psychology course. For the modified photovoice activity, the participants took three photos related to their perceptions of (1) health, (2) health protective factors, and (3) health risk factors. The data interpretation involved a thematic analysis of these photos and captions; a narrative analysis to distinguish between documentary and symbolic photos; and a descriptive analysis of the photo production. Results. Eighty-seven students completed the photography assignment. The mean age was 22.1 years (SD = 1.1). Most photos (91%) documented real-life health behaviours. Some photos (9%) used everyday objects such as sunflowers to create symbols related to health. A photo series showed a model of the human brain in different environments and activities. Conclusions. Student participation in the photovoice activity appeared to strengthen observation and interpretation skills, which are essential to client care. Students used this opportunity to reflect on their own lives and environments and show their perceptions of health, health protective factors, and health risks. The activity planted seeds for changes in students’ health perceptions and critical thinking. Future research could explore whether participation in a modified photovoice activity as experiential learning in a required health psychology course contributes to changes in master’s-level nursing students’ personal health behaviours and client care. Full article

In this paper, we have demonstrated a narrow linewidth high power fiber laser emitting at a short wavelength of ~1050 nm. The fiber laser is based on a structure of master oscillator power amplification (MOPA) with an optimized fiber Bragg-grating-based laser cavity as the seed. Both stimulated Brillouin scattering (SBS) and stimulated Raman scattering (SRS) effects have been effectively suppressed by using a long passive fiber between the seed and the amplifier. Based on the fiber amplifier, we have ultimately boosted the narrow linewidth laser from ~40 W to 3.2 kW with a slope efficiency of 85.1% and a 3-dB linewidth of ~0.1 nm. The SRS suppression ratio of the laser is ~29.7 dB at maximum power. Due to our fiber mode control strategies, the beam quality always stays near-diffraction-limited while amplifying, and the measured M² factor is ~1.4 at the maximum power. Further increase in output power is limited by the SBS effect. Full article

In recognition of the critical role of residency programs in narrowing healthcare inequalities, Global Health scholarships were introduced at Mbarara University of Science and Technology (MUST) in 2011. Since then, at least 154 postgraduate students in priority programs have benefited. We conducted an online cross-sectional survey to examine how the scholarships and beneficiaries have impacted MUST and the community. Fifty (50) beneficiaries, representing 32.5%, responded, of whom 36 (72%) were alumni. Most respondents were males (n = 30; 60%) pursing Master of Medicine (n = 29; 58%) or Master of Nursing Science (n = 20; 40%) programs. The scholarship schemes included First Mile (n = 29; 58%), Kayanja (n = 12; 24%), Paiko (n = 5; 10%) and Seed (n = 4; 8%). The majority of the scholarships supported both tuition and research fees (n = 41; 82%), the rest being partial. Career advancement was undertaken by eight (16%) of the scholars in the form of fellowships (n = 3; 6%), other masters (n = 3; 6%) and PhDs (n = 3; 6%), with some students having attained a combination of these. All scholars belonged to at least one health professional association. Over 88% (n = 32) of the alumni and 28% (n = 4) of the students were employed. The majority of those employed were in the public sector (n = 24; 66.7%), mainly the health sector (n = 18; 50%), academia (n = 14; 38.9) or both (n = 4; 11.1%). There was a high impact on health care provision, undergraduate training and research carried out by the scholars both during training and post-graduation. High levels of career satisfaction, scholarship impact and academic program relevance were reported. The findings provide insights on how low-fund specialty scholarships can have a far-reaching impact on local training, health care and research in low- and middle-income countries. Full article

In this paper, we develop a kW-level high-repetition-rate nanosecond master oscillator power amplifier (MOPA) laser system, employing a structure of fiber, Nd:YVO₄, and Nd:YAG hybrid amplification. A tunable fiber seed source is used for adjustable pulse repetition frequency and pulse width. The Nd:YVO₄ pre-amplifier, which is dual-end-pumped, achieves high gain while maintaining good beam quality, and the high-power side-pumped Nd:YAG slab main-amplifier enables efficient power amplification. The repetition rate of the output laser can be adjusted within the range of 1~20 kHz, and the pulse width can be tuned within the range of 10~300 ns. The seed output is 6 mW at a repetition frequency of 20 kHz; we achieve an average output power of 1240 W with a total power extraction efficiency of 39.1% and single-pulse energy of 62 mJ at a pulse width of 301 ns. This parameter-controllable high-power laser holds promise for applications in the laser cleaning of complex surface contaminants. Full article

Obesity has a great impact on adipose tissue biology, based on its function as a master regulator of energy balance. Brown adipose tissue (BAT) undergoes remodeling, and its activity declines in obese subjects due to a whitening process. The anti-obesity properties of fruit extracts have been reported. The effects of tart cherry against oxidative stress, inflammation, and the whitening process in the BAT of obese rats were investigated. Intrascapular BAT (iBAT) alterations and effects of Prunus cerasus L. were debated in rats fed for 17 weeks with a high-fat diet (DIO), in DIO supplemented with seed powder (DS), and with seed powder plus the juice (DJS) of tart cherry compared to CHOW rats fed with a normo-caloric diet. iBAT histologic observations revealed a whitening process in DIO rats that was reduced in the DS and DJS groups. A modulation of uncoupling protein-1 (UCP-1) protein and gene expression specifically were detected in the obese phenotype. An upregulation of UCP-1 and related thermogenic genes after tart cherry intake was detected compared to the DIO group. Metabolic adjustment, endoplasmic reticulum stress, protein carbonylation, and the inflammatory microenvironment in the iBAT were reported in DIO rats. The analysis demonstrated an iBAT modulation that tart cherry promoted. In addition to our previous results, these data confirm the protective impact of tart cherry consumption on obesity. Full article

α-Linolenic acid (ALA) is an important nutrient component in rapeseed oil, and rapeseed breeders want to either restrain or enhance the function of fatty acid desaturases (FADs) in the ALA biosynthesis pathway. To determine the reason for the upregulation of rapeseed BnFAD genes in two high-ALA accessions, R8Q10 and YH25005, we compared their transcriptome profiles in the seed at 24 days after pollination (DAP) with those of two low-ALA lines, A28 and SW. The expression levels of twenty-eight important genes in the seed samples at 20, 27, and 34 DAP were also investigated using an RT-qPCR. The expression levels of genes involved in flavonoid and proanthocyanidin synthesis, including BnCHS, BnCHI, BnDFR, BnFLS1, BnLDOX, BnBAN, BnTT10, and BnTT12 and genes encoding the transcription factors BnTT1, BnTT2, BnTT8, and BnTT16 were lower in R8Q10 and YH25005 than in A28 and SW. The expression levels of genes encoding master transcription factors in embryo development, such as BnLEC1, BnABI3, BnFUS3, BnL1L, BnAREB3, and BnbZIP67, were elevated significantly in the two high-ALA accessions. Combined with previous results in the Arabidopsis and rapeseed literature, we speculated that the yellow-seededness genes could elevate the activity of BnLEC1, BnABI3, BnFUS3, and BnbZIP67, etc., by reducing the expression levels of several transparent testa homologs, resulting in BnFAD3 and BnFAD7 upregulation and the acceleration of ALA synthesis. Yellow-seededness is a favorable factor to promote ALA synthesis in the two high-ALA accessions with the yellow-seeded trait. These findings provide initial insights into the transcriptomic differences between high-/low-ALA germplasms and a theoretic basis for seed quality breeding. Full article

We report on a 1064 nm master oscillator power amplifier (MOPA) system based on pulse-modulated laser diode seed sources combined with fiber preamplifiers and a Yb-doped tapered double-clad fiber (T-DCF) amplifier used as an all-fiber master oscillator and a two-stage side-pumped solid-state power amplifier. The combination of two master oscillators and a single power amplifier allowed us to obtain pulses with a duration ranging from 10 ns to 10 μs with energy up to 137 mJ at 100 Hz. For the first time, we demonstrate a widely tunable pulse duration and a solid-state MOPA system with over 100 mJ energy based on a T-DCF fiber seed laser. Full article

The structures of histone complexes are master keys to epigenetics. Linear histone peptide tails often bind to shallow pockets of reader proteins via weak interactions, rendering their structure determination challenging. In the present study, a new protocol, PepGrow, is introduced. PepGrow uses docked histone fragments as seeds and grows the full peptide tails in the reader-binding pocket, producing atomic-resolution structures of histone–reader complexes. PepGrow is able to handle the flexibility of histone peptides, and it is demonstrated to be more efficient than linking pre-docked peptide fragments. The new protocol combines the advantages of popular program packages and allows fast generation of solution structures. AutoDock, a force-field-based program, is used to supply the docked peptide fragments used as structural seeds, and the building algorithm of Modeller is adopted and tested as a peptide growing engine. The performance of PepGrow is compared to ten other docking methods, and it is concluded that in situ growing of a ligand from a seed is a viable strategy for the production of complex structures of histone peptides at atomic resolution. Full article

Porcine reproductive and respiratory syndrome virus (PRRSV) is major economic problem given its effects on swine health and productivity. Therefore, we evaluated the genetic stability of a codon pair de-optimized (CPD) PRRSV, E38-ORF7 CPD, as well as the master seed passage threshold that elicited an effective immune response in pigs against heterologous virus challenge. The genetic stability and immune response of every 10th passage (out of 40) of E38-ORF7 CPD was analyzed through whole genome sequencing and inoculation in 3-week-old pigs. E38-ORF7 CPD passages were limited to 20 based on the full-length mutation analysis and animal test results. After 20 passages, the virus could not induce antibodies to provide effective immunity and mutations accumulated in the gene, which differed from the CPD gene, presenting a reason for low infectivity. Conclusively, the optimal passage number of E38-ORF7 CPD is 20. As a vaccine, this may help overcome the highly diverse PRRSV infection with substantially enhanced genetic stability. Full article

In pumpkin (Cucurbita moschata), the naked or hull-less seed phenotype has great benefits for breeding this crop for oil or snack use. We previously identified a naked seed mutant in this crop. In this study, we report genetic mapping, identification, and characterization of a candidate gene for this mutation. We showed that the naked seed phenotype is controlled by a single recessive gene (N). The bulked segregant analysis identified a 2.4 Mb region on Chromosome 17 with 15 predicted genes. Multiple lines of evidence suggested that CmoCh17G004790 is the most probable candidate gene for the N locus which encodes a NAC transcription factor WALL THICKENING PROMOTING FACTOR 1 (CmNST1). No nucleotide polymorphism or structural variation was found in the genomic DNA sequences of CmNST1 between the mutant and the wildtype inbred line (hulled seed). However, the cDNA sequence cloned from developing seed coat samples of the naked seed mutant was 112 bp shorter than that from the wildtype which is due to seed coat-specific alternative splicing in the second exon of the mutant CmNST1 transcript. The expression level of CmNST1 in the developing seed coat was higher in the mutant than in the wildtype during early seed coat development which was reversed later. Transcriptomic profiling with RNA-Seq at different stages of seed development in the mutant and wildtype revealed a critical role of CmNST1 as a master regulator for the lignin biosynthesis pathway during seed coat development while other NAC and MYB transcription factors were also involved in forming a regulatory network for the building of secondary cell walls. This work provides a novel mechanism for the well-characterized NST1 transcription factor gene in regulating secondary cell wall development. The cloned gene also provides a useful tool for marker-assisted breeding of hull-less C. moschata varieties. Full article

We demonstrated a narrow-linewidth high-power Yb-doped polarization-maintaining (PM) fiber laser with near-diffraction-limited beam. The laser system consisted of a phase-modulated single-frequency seed source and four-stage amplifiers in the master oscillator power amplifier configuration. A quasi-flat-top pseudo random binary sequence (PRBS) phase-modulated single-frequency laser with a linewidth of 8 GHz was injected into the amplifiers for suppressing stimulated Brillouin scattering. The quasi-flat-top PRBS signal was readily generated from the conventional PRBS signal. The maximum output power was 2.01 kW with polarization extinction ratio (PER) of ~15 dB. The beam quality (M2) was less than 1.3 over the power scaling range. Full article

A high-power, narrow-linewidth, continuous-wave, thulium-doped fiber laser (TDFL) based on a master-oscillator power-amplifier (MOPA) was experimentally demonstrated. The main oscillator (seed source) yielded 0.64 W of narrow-linewidth laser output at a central wavelength of 1940.32 nm and a 3 dB spectral bandwidth of 0.05 nm. The output narrow-linewidth laser from the main oscillator was amplified by two-stage, cladding-pumped, thulium-doped, all-fiber amplifiers. The main amplifier yielded 26 W of narrow-linewidth laser at a central wavelength of 1940.33 nm. The slope efficiency of the main amplifier was approximately 55.6%. Significant residual pumping light component in the output laser was not observed. During the amplification process, no stimulated Brillouin scattering (SBS) effect, strong amplified spontaneous emission (ASE) effect, and parasitic lasers were observed at the reverse monitoring end. Moreover, the output power was only limited by the incident pump power and the output power had a good stability in a 50 min monitoring period. Full article

Parthenocarpy and stenospermocarpy are the two mechanisms underlying the seedless fruit set program. Seedless fruit occurs naturally and can be produced using hormone application, crossbreeding, or ploidy breeding. However, the two types of breeding are time-consuming and sometimes ineffective due to interspecies hybridization barriers or the absence of appropriate parental genotypes to use in the breeding process. The genetic engineering approach provides a better prospect, which can be explored based on an understanding of the genetic causes underlying the seedlessness trait. For instance, CRISPR/Cas is a comprehensive and precise technology. The prerequisite for using the strategy to induce seedlessness is identifying the crucial master gene or transcription factor liable for seed formation/development. In this review, we primarily explored the seedlessness mechanisms and identified the potential candidate genes underlying seed development. We also discussed the CRISPR/Cas-mediated genome editing approaches and their improvements. Full article