Phase duration and resurgence

Abstract It is standard practice to ferment white wines at low temperatures (10-18 °C). However, low temperatures increase fermentation duration and risk of problem ferments, leading to significant costs. The lag duration at fermentation initiation is heavily impacted by temperature; therefore, identification of Saccharomyces cerevisiae genes influencing fermentation kinetics is of interest for winemaking. We selected 28 S. cerevisiae BY4743 single deletants, from a prior list of open reading frames (ORFs) mapped to quantitative trait loci (QTLs) on chromosomes VII and XIII, influencing the duration of fermentative lag time. Five BY4743 deletants, Δapt1, Δcgi121, Δclb6, Δrps17a, and Δvma21, differed significantly in their fermentative lag duration compared to BY4743 in synthetic grape must (SGM) at 15 °C, over 72 h. Fermentation at 12.5 °C for 528 h confirmed the longer lag times of BY4743 Δcgi121, Δrps17a, and Δvma21. These three candidate ORFs were deleted in S. cerevisiae RM11-1a and S288C to perform single reciprocal hemizygosity analysis (RHA). RHA hybrids and single deletants of RM11-1a and S288C were fermented at 12.5 °C in SGM and lag time measurements confirmed that the S288C allele of CGI121 on chromosome XIII, encoding a component of the EKC/KEOPS complex, increased fermentative lag phase duration. Nucleotide sequences of RM11-1a and S288C CGI121 alleles differed by only one synonymous nucleotide, suggesting that intron splicing, codon bias, or positional effects might be responsible for the impact on lag phase duration. This research demonstrates a new role of CGI121 and highlights the applicability of QTL analysis for investigating complex phenotypic traits in yeast.

Download Full-text

Predictive Modeling for the Growth of Salmonella spp. in Liquid Egg White and Application of Scenario-Based Risk Estimation

Microorganisms ◽

10.3390/microorganisms9030486 ◽

2021 ◽

Vol 9 (3) ◽

pp. 486

Author(s):

Mi Seon Kang ◽

Jin Hwa Park ◽

Hyun Jung Kim

Keyword(s):

Predictive Model ◽

Scenario Analysis ◽

Specific Growth ◽

Risk Estimation ◽

Egg White ◽

Lag Phase ◽

Salmonella Spp ◽

Baseline Model ◽

Phase Duration ◽

Root Model

The objective of the study was to develop a predictive model of Salmonella spp. growth in pasteurized liquid egg white (LEW) and to estimate the salmonellosis risk using the baseline model and scenario analysis. Samples were inoculated with six strains of Salmonella, and bacterial growth was observed during storage at 10–37 °C. The primary models were developed using the Baranyi model for LEW. For the secondary models, the obtained specific growth rate (μmax) and lag phase duration were fitted to a square root model and Davey model, respectively, as functions of temperature (R2 ≥ 0.98). For μmax, the values were satisfied within an acceptable range (Af, Bf: 0.70–1.15). The probability of infection (Pinf) due to the consumption of LEW was zero in the baseline model. However, scenario analysis suggested possible salmonellosis for the consumption of LEW. Because Salmonella spp. proliferated much faster in LEW than in egg white (EW) during storage at 20 and 30 °C (p < 0.01), greater Pinf may be obtained for LEW when these products are stored at the same conditions. The developed predictive model can be applied to the risk management of Salmonella spp. along the food chain, including during product storage and distribution.

Download Full-text

Biomethane Potential of Sludges from a Brackish Water Fish Hatchery

Applied Sciences ◽

10.3390/app11020552 ◽

2021 ◽

Vol 11 (2) ◽

pp. 552

Author(s):

Francesco da Borso ◽

Alessandro Chiumenti ◽

Giulio Fait ◽

Matia Mainardis ◽

Daniele Goi

Keyword(s):

Brackish Water ◽

Gompertz Model ◽

Experimental Tests ◽

Lag Phase ◽

Phase Duration ◽

Fish Hatchery ◽

Volatile Solids ◽

Water Recirculation ◽

Methane Potential ◽

Intensive Aquaculture

The development of intensive aquaculture is facing the challenge of the sustainable management of effluents. The reproductive sectors (i.e., hatcheries) mainly use water recirculation systems (RAS), which discharge a portion of wastewater. Anaerobic digestion (AD) could reduce the environmental impact of this waste stream while producing biogas. The study is focused on the biochemical methane potential (BMP) of brackish fish hatchery sludges. Wastewater was concentrated by microfiltration and sedimentation and thickened sludges were treated in a BMP system with different inoculum/substrate (I/S) volatile solids ratios (from 50:1 to no inoculum). The highest I/S ratio showed the highest BMP (564.2 NmL CH4/g VS), while different I/S ratios showed a decreasing trend (319.4 and 127.7 NmL CH4/g VS, for I/S = 30 and I/S = 3). In absence of inoculum BMP resulted of 62.2 NmL CH4/g VS. The kinetic analysis (modified Gompertz model) showed a good correlation with the experimental data, but with a long lag-phase duration (from 14.0 to 5.5 days) in particular with the highest I/S. AD applied to brackish water sludges can be a promising treatment with interesting methane productions. For a continuous, full-scale application further investigation on biomass adaptation to salinity and on retention times is needed. Further experimental tests are ongoing.

Download Full-text

Resistance of Hypoxic Cells to Ionizing Radiation Is Mediated in Part via Hypoxia-Induced Quiescence

Cells ◽

10.3390/cells10030610 ◽

2021 ◽

Vol 10 (3) ◽

pp. 610

Author(s):

Apostolos Menegakis ◽

Rob Klompmaker ◽

Claire Vennin ◽

Aina Arbusà ◽

Maartje Damen ◽

...

Keyword(s):

Cell Cycle ◽

Cell Lines ◽

Cancer Cell ◽

Radiation Treatment ◽

Large Fraction ◽

Radiation Sensitivity ◽

Cancer Cell Lines ◽

Cycle Phase ◽

Multicellular Spheroids ◽

Phase Duration

Double strand breaks (DSBs) are highly toxic to a cell, a property that is exploited in radiation therapy. A critical component for the damage induction is cellular oxygen, making hypoxic tumor areas refractory to the efficacy of radiation treatment. During a fractionated radiation regimen, these hypoxic areas can be re-oxygenated. Nonetheless, hypoxia still constitutes a negative prognostic factor for the patient’s outcome. We hypothesized that this might be attributed to specific hypoxia-induced cellular traits that are maintained upon reoxygenation. Here, we show that reoxygenation of hypoxic non-transformed RPE-1 cells fully restored induction of DSBs but the cells remain radioresistant as a consequence of hypoxia-induced quiescence. With the use of the cell cycle indicators (FUCCI), cell cycle-specific radiation sensitivity, the cell cycle phase duration with live cell imaging, and single cell tracing were assessed. We observed that RPE-1 cells experience a longer G1 phase under hypoxia and retain a large fraction of cells that are non-cycling. Expression of HPV oncoprotein E7 prevents hypoxia-induced quiescence and abolishes the radioprotective effect. In line with this, HPV-negative cancer cell lines retain radioresistance, while HPV-positive cancer cell lines are radiosensitized upon reoxygenation. Quiescence induction in hypoxia and its HPV-driven prevention was observed in 3D multicellular spheroids. Collectively, we identify a new hypoxia-dependent radioprotective phenotype due to hypoxia-induced quiescence that accounts for a global decrease in radiosensitivity that can be retained upon reoxygenation and is absent in cells expressing oncoprotein E7.

Download Full-text

The duration of the active phase on surge-type glaciers: contrasts between Svalbard and other regions

Journal of Glaciology ◽

10.1017/s0022143000005827 ◽

1991 ◽

Vol 37 (127) ◽

pp. 388-400 ◽

Cited By ~ 144

Author(s):

Julian A. Dowdeswell ◽

Gordon S. Hamilton ◽

Jon Ove Hagen

Keyword(s):

Time Series ◽

North America ◽

Active Phase ◽

Aerial Photographs ◽

Polar Ice ◽

Phase Duration ◽

Field Surveys ◽

The World ◽

Glacier Surges ◽

Fast Motion

AbstractMany glaciers in Svalbard and in other glacierized areas of the world are known to surge. However, the time series of observations required to assess the duration of fast motion is very restricted. Data on active-phase duration in Svalbard come from aerial photographs, satellite imagery, field surveys and airborne reconnaissance. Evidence on surge duration is available for eight Svalbard ice masses varying from 3 to 1250 km2. Worldwide, active-phase duration is recorded for less than 50 glaciers. Few observations are available on high polar ice masses. The duration of the active phase is significantly longer for Svalbard glaciers than for surge-type glaciers in other areas from which data are available. In Svalbard, the active phase may last from 3 to 10 years. By contrast, a surge duration of 1–2 years is more typical of ice masses in northwest North America, Iceland and the Pamirs. Ice velocities during the protracted active phase on Svalbard glaciers are considerably lower than those for many surge-type glaciers in these other regions. Mass is transferred down-glacier more slowly but over a considerably longer period. Svalbard surge-type glaciers do not exhibit the very abrupt termination of the active phase, over periods of a few days, observed for several Alaskan glaciers. The duration of the active phase in Svalbard is not dependent on parameters related to glacier size. The quiescent phase is also relatively long (50–500 years) for Svalbard ice masses. Detailed field monitoring of changing basal conditions through the surge cycle is required from surge-type glaciers in Svalbard in order to explain the significantly longer length of the active phase for glaciers in the archipelago, which may also typify other high polar ice masses. The finding that surge behaviour, in the form of active-phase duration, shows systematic differences between different regions and their environments has important implications for understanding the processes responsible for glacier surges.

Download Full-text

Occurrence and timely management of problems requiring prompt intervention among Indigenous compared with non-Indigenous Australian palliative care patients: a multijurisdictional cohort study

BMJ Open ◽

10.1136/bmjopen-2020-042268 ◽

2021 ◽

Vol 11 (3) ◽

pp. e042268

Author(s):

John A Woods ◽

Judith M Katzenellenbogen ◽

Kevin Murray ◽

Claire E Johnson ◽

Sandra C Thompson

Keyword(s):

Palliative Care ◽

Cohort Study ◽

Cultural Barriers ◽

Survival Models ◽

Indigenous Australians ◽

Specialist Palliative Care ◽

Indigenous Australian ◽

Phase Duration ◽

Core Element ◽

Similar Frequency

ObjectivesAnticipation and prompt relief of symptoms among patients with a life-limiting illness is a core element of palliative care. Indigenous Australians commonly encounter cultural barriers in healthcare that may impair outcomes. The Palliative Care Outcomes Collaboration collects patient care data for the purposes of continuous quality improvement and benchmarking, with each recorded care episode divided into phases that reflect a patient’s condition. We aimed to investigate differences between Indigenous and non-Indigenous patients in the occurrence and duration of ‘unstable’ phases (which indicate unanticipated deterioration in a patient’s condition or circumstances), and determine attainment of the relevant benchmark (resolution of unstable phases in ≤3 days in 90% of cases) for both groups.DesignCohort study.SettingAustralia-wide hospital-based and community-based specialist palliative care (1 January 2010 to 30 June 2015).Participants139 556 (1502 Indigenous and 138 054 non-Indigenous) adult patients.Outcome measuresIndigenous and non-Indigenous patients were compared on (1) the risk of a phase being categorised as unstable, (2) the duration of unstable phases, and (3) the risk of unstable phases being prolonged (>3 days). Crude and adjusted estimates were produced from three-level robust Poisson regression and complementary log-log discrete time survival models.ResultsUnstable phases occurred with similar frequency overall among Indigenous and non-Indigenous patients (adjusted relative risks 1.06; 95% CI 1.00 to 1.11; not significant after correction for multiple comparisons). The duration and risk of prolongation of unstable phases were similar in both patient groups, with no significant differences evident among subgroups. The benchmark was not met for either Indigenous or non-Indigenous patients (unstable phase duration >3 days in 24.3% vs 25.5%; p=0.398).ConclusionsDespite well-documented shortcomings of healthcare for Indigenous Australians, there is no clear evidence of greater occurrence or prolongation of unanticipated problems among Indigenous patients accessing specialist palliative care services in hospital or the community.

Download Full-text

The effects of second and third phase duration on defibrillation efficacy of triphasic rectangle waveforms

Resuscitation ◽

10.1016/j.resuscitation.2016.02.018 ◽

2016 ◽

Vol 102 ◽

pp. 57-62 ◽

Cited By ~ 2

Author(s):

Ce Tang ◽

Pei Wang ◽

Yushun Gong ◽

Liang Wei ◽

Yongqin Li ◽

...

Keyword(s):

Phase Duration ◽

Third Phase

Download Full-text

Phase-Specific Force and Time Predictors of Standing Long Jump Distance

Journal of Applied Biomechanics ◽

10.1123/jab.2021-0093 ◽

2021 ◽

pp. 1-8

Author(s):

John R. Harry ◽

John Krzyszkowski ◽

Luke D. Chowning ◽

Kristof Kipp

Keyword(s):

National Collegiate Athletic Association ◽

Reaction Force ◽

Vertical Force ◽

Jump Height ◽

Strength Index ◽

Phase Duration ◽

Standing Long Jump ◽

Jump Distance ◽

Long Jump ◽

Force Time

This study sought to identify potential predictors of standing long jump (SLJ) performance using force–time strategy metrics within the unloading, eccentric yielding, eccentric braking, and concentric phases. Fifteen National Collegiate Athletic Association division 1 male soccer players (19 [1] y, 1.81 [0.94] m, 80.3 [22.4] kg) performed 3 maximum-effort SLJs, while 3-dimensional ground reaction force (GRF) data were obtained. Regularized regression models were used to investigate associations between force–time strategy metrics and 2 metrics of SLJ performance (ie, jump distance and modified reactive strength index). Jump height and eccentric yielding time were the only predictors of jump distance that also demonstrated large correlations to jump distance. Anterior–posterior unloading yank, average concentric vertical force, and concentric phase duration were the only predictors of modified reactive strength index that also demonstrated large correlations to modified reactive strength index. To maximize SLJ distance in high-level soccer athletes, human performance practitioners could design interventions to drive changes in strategy to increase jump height and decrease eccentric yielding time. To improve SLJ explosiveness, interventions to drive changes in unloading and concentric force application and decrease concentric time could be emphasized. Importantly, unique variable combinations can be targeted when training for SLJ distance and explosiveness adaptations.

Download Full-text