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Fermentation ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 23
Author(s):  
Karthick Murugan Palanisamy ◽  
Gaanty Pragas Maniam ◽  
Ahmad Ziad Sulaiman ◽  
Mohd Hasbi Ab. Rahim ◽  
Natanamurugaraj Govindan ◽  
...  

Biomass and lipid production by the marine centric diatom Thalassiosira pseudonana were characterized in media based on palm oil mill effluent (POME) as a source of key nutrients. The optimal medium comprised 20% by volume POME, 80 µM Na2SiO3, and 35 g NaCl L−1 in water at pH ~7.7. In 15-day batch cultures (16:8 h/h light–dark cycle; 200 µmol photons m−2 s−1, 26 ± 1 °C) bubbled continuously with air mixed with CO2 (2.5% by vol), the peak concentration of dry biomass was 869 ± 14 mg L−1 corresponding to a productivity of ~58 mg L−1 day−1. The neutral lipid content of the biomass was 46.2 ± 1.1% by dry weight. The main components of the esterified lipids were palmitoleic acid methyl ester (31.6% w/w) and myristic acid methyl ester (16.8% w/w). The final biomass concentration and the lipid content were affected by the light–dark cycle. Continuous (24 h light) illumination at the above-specified irradiance reduced biomass productivity to ~54 mg L−1 day−1 and lipid content to 38.1%.


2021 ◽  
Author(s):  
Uma T Plenz ◽  
Patrick O Kanold

Mice are one of several common animal models in neuroscience and mouse behavior is becoming increasingly relevant. Mice are housed either in groups or alone in standard cages during which they show a variety of different behaviors. Moreover, housing conditions might alter the behavior of the mice as do social interactions. When given access to running wheels as an environmental enrichment, mice tend to run long distances preferentially during their dark cycle. However, it is currently not well understood whether and how mice utilize running wheels when single-housed or group-housed. Here we developed a low-cost running wheel data acquisition system to study running in adult C57BL/6 mice at high temporal resolution under different social conditions. As expected, adult C57BL/6 mice prefer to run in stretches during the dark cycle and mostly rest during the light cycle. When single-housed, running bouts occur independent from each other as indicated by an exponential decaying autocorrelation. In contrast, mice run ~50% less when housed in groups of n = 3 and their temporal pattern of running exhibits a power law decay in the autocorrelation indicative of potential social interactions. Our results demonstrate that running wheels are a limited resource for which mice compete for when they are group-housed, thereby reducing their overall running activity.


2021 ◽  
Vol 22 (24) ◽  
pp. 13276
Author(s):  
Shihui Liu ◽  
Mary Miyaji ◽  
Osamu Hosoya ◽  
Toshihiko Matsuo

Purpose: NK-5962 is a key component of photoelectric dye-coupled polyethylene film, designated Okayama University type-retinal prosthesis (OUReP™). Previously, we found that NK-5962 solution could reduce the number of apoptotic photoreceptors in the eyes of the Royal College of Surgeons (RCS) rats by intravitreal injection under a 12 h light/dark cycle. This study aimed to explore possible molecular mechanisms underlying the anti-apoptotic effect of NK-5962 in the retina of RCS rats. Methods: RCS rats received intravitreal injections of NK-5962 solution in the left eye at the age of 3 and 4 weeks, before the age of 5 weeks when the speed in the apoptotic degeneration of photoreceptors reaches its peak. The vehicle-treated right eyes served as controls. All rats were housed under a 12 h light/dark cycle, and the retinas were dissected out at the age of 5 weeks for RNA sequence (RNA-seq) analysis. For the functional annotation of differentially expressed genes (DEGs), the Metascape and DAVID databases were used. Results: In total, 55 up-regulated DEGs, and one down-regulated gene (LYVE1) were found to be common among samples treated with NK-5962. These DEGs were analyzed using Gene Ontology (GO) term enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Reactome pathway analyses. We focused on the up-regulated DEGs that were enriched in extracellular matrix organization, extracellular exosome, and PI3K–Akt signaling pathways. These terms and pathways may relate to mechanisms to protect photoreceptor cells. Moreover, our analyses suggest that SERPINF1, which encodes pigment epithelium-derived factor (PEDF), is one of the key regulatory genes involved in the anti-apoptotic effect of NK-5962 in RCS rat retinas. Conclusions: Our findings suggest that photoelectric dye NK-5962 may delay apoptotic death of photoreceptor cells in RCS rats by up-regulating genes related to extracellular matrix organization, extracellular exosome, and PI3K–Akt signaling pathways. Overall, our RNA-seq and bioinformatics analyses provide insights in the transcriptome responses in the dystrophic RCS rat retinas that were induced by NK-5962 intravitreal injection and offer potential target genes for developing new therapeutic strategies for patients with retinitis pigmentosa.


2021 ◽  
Vol 45 (1) ◽  
Author(s):  
Moyosore Joseph Adegbeye ◽  
Oluwatosin Bode Omotoso ◽  
Adebowale Noah Fajemisin ◽  
Samuel Olanrewaju Aro ◽  
Damilola Deborah Obadare ◽  
...  

Abstract Background This study was conducted to evaluate the impact of time of feeding on the performance of WAD goats during pregnancy, and to assess how the time of feeding of the dam affect the growth of their kids’ postpartum. Twelve (12) pregnant does were used in the pre-partum and in the postpartum, the same 12 lactating does and their 12 kids (1 kid per doe) were used. The dams were randomly distributed into three treatments and were fed once daily either in the morning, noon, or evening at 0600 h, 12:00 h and 18:00 h respectively under the natural light–dark cycle. Result Serum creatinine in noon-fed does was higher (P = 0.005) than in morning and evening-fed does. In addition, low density lipoprotein in morning-fed gravid does was the high (P = 0.007) compared to noon-fed does while the evening-fed does had the lowest. During postpartum, morning and noon-fed dams consumed more feed (forage, concentrate, and total daily feed intake) than evening-fed dams (P ≤ 0.006). Kid weight of morning-fed does was numerically higher than noon-fed does, which was higher than kids of evening-fed does. Conclusion This study shows that time of feeding did not affect the performance of pregnant WAD goats. However, it has the potential to influence the serum parameters of pregnant animals. It also showed that time of feeding influences maternal feed intake postpartum and can influence the growth of the kids.


2021 ◽  
Vol 15 ◽  
Author(s):  
Julien Colomb ◽  
York Winter

Automated mouse phenotyping through the high-throughput analysis of home cage behavior has brought hope of a more effective and efficient method for testing rodent models of diseases. Advanced video analysis software is able to derive behavioral sequence data sets from multiple-day recordings. However, no dedicated mechanisms exist for sharing or analyzing these types of data. In this article, we present a free, open-source software actionable through a web browser (an R Shiny application), which performs an analysis of home cage behavioral sequence data, which is designed to spot differences in circadian activity while preventing p-hacking. The software aligns time-series data to the light/dark cycle, and then uses different time windows to produce up to 162 behavior variables per animal. A principal component analysis strategy detected differences between groups. The behavior activity is represented graphically for further explorative analysis. A machine-learning approach was implemented, but it proved ineffective at separating the experimental groups. The software requires spreadsheets that provide information about the experiment (i.e., metadata), thus promoting a data management strategy that leads to FAIR data production. This encourages the publication of some metadata even when the data are kept private. We tested our software by comparing the behavior of female mice in videos recorded twice at 3 and 7 months in a home cage monitoring system. This study demonstrated that combining data management with data analysis leads to a more efficient and effective research process.


2021 ◽  
Author(s):  
Casey O Diekman ◽  
Amitabha Bose

While the vast majority of humans are able to entrain their circadian rhythm to the 24-hour light-dark cycle, there are numerous individuals who are not able to do so due to disease or societal reasons. We use computational and mathematical methods to analyze a well-established model of human circadian rhythms to address cases where individuals do not entrain to the 24-hour light-dark cycle, leading to misalignment of their circadian phase. For each case, we provide a mathematically justified strategy for how to minimize circadian misalignment. In the case of non-24-hour sleep-wake disorder, we show why appropriately timed bright light therapy induces entrainment. With regard to shift work, we explain why reentrainment times following transitions between day and night shifts are asymmetric, and how higher light intensity enables unusually rapid reentrainment after certain transitions. Finally, with regard to teenagers who engage in compensatory catch-up sleep on weekends, we propose a rule of thumb for sleep and wake onset times that minimizes circadian misalignment due to this type of social jet lag. In all cases, the primary mathematical approach involves understanding the dynamics of entrainment maps that measure the phase of the entrained rhythm with respect to the daily onset of lights.


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