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Assessment of the impacts of climate change on the potato yield of Prince Edward Island
No full textAccording to the published sixth assessment report (AR6) of the Intergovernmental Panel on Climate Change (IPCC), each of the last four decades has been successively warmer than any preceding decade, causing global climate change. Environmental factors are being impacted by climate change and, currently, one of the biggest challenges of the world at present. Climate change impacts all sectors directly (e.g., physical damage from heat waves, precipitation, bushfires, erosion, and floods) or indirectly (e.g., effects of extreme events or climate change, such as reduction in income or supply chain disruption). Climate change has impacted global crop yield, and it is crucial to develop an adaptation strategy to the effect of increasing climate variability on crop growth and development. Potatoes are a staple non-grain crop consumed globally, sensitive to environmental factors determining its growth, development, and final yield. Several studies suggested that increased carbon dioxide (CO2) could enhance potato growth; on the other hand, increased CO2 concentration leads to an increase in temperature, causing global warming, which ultimately has undesirable effects on the growth and development of potato crops. In Prince Edward Island (PEI), potatoes stand out as an important staple crop, and PEI is recognized as a major exporter of potatoes. It is imperative for local farmers and decision-makers to understand how climate change will impact the potato industry in PEI, which could affect food security and the economy. Based on the literature, some research gaps served as the basis for this study. Specifically, there has not been a study that has assessed the impacts of climate change on potato yields using the DSSAT model. In addition, the climate change scenarios used in previous studies are from the CMIP3 or CMIP5 datasets rather than the latest CMIP6 dataset (Our World in Data, 2022; World Bank Group, 2022). Previous studies that used the DSSAT model did not consider the combined effects of multiple climate variables on potato yields, such as the combined effect of temperature, CO2, and precipitation. This study uses the Decision Support System for Agrotechnology Transfer (DSSAT) model to assess the climate change impacts on potato yield using soil data, weather data, and management practices data as a function of soil-plant-atmosphere dynamics, and three key steps are being
taken to achieve this objective. Comprehensively review the literature on assessing climate change's impacts on global potato yields using the DSSAT model, identifying the knowledge gaps. Collecting the required data to set up the DSSAT model, which includes potato management, soil, weather and future climate scenarios data. Calibrating, validating the model, and assessing the impacts of climate change on potato yields in PEI. Seven global climate models (GCMs) “CanESM5, FGOAL-G3, GFDL-ESM4, MIROC6, MRIESM2, IPSL-CM6A LR, and EC-Earth3-Veg” was used to generate the IPCC Coupled Model
Intercomparison Project Phase 6 (CMIP6) data under Shared Socioeconomic Pathways (SSPs) emission scenarios “SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5” for the 2050s (2045-2055), 2070s (2065-2075), and 2090s (2085-2095). The combined effect of temperature, precipitation, and CO2 was assessed for future scenarios compared to historical (1995-2014). The model showed a good performance with a coefficient of determination R2 of 0.90. The climate change impact assessment suggested a decline (2% to 80%) in potato yields in PEI as emission scenarios increased and was significant towards the end of the century. This study shows a significant decline in the future potato yields in PEI due to the negative impacts of climate change. This study can help PEI local potato farmers and stakeholders better understand the ongoing and future climate change challenges related to potato yield to provide scientific bases for developing adaptation strategies
Cold temperatures as a source of stress: seasonality, sand burrowing and hemocyanin levels in Atlantic Canada sandy beach amphipods
No full textSandy beach species are adapted to a harsh physical habitat, but for those living at relatively high latitudes, the cold, often freezing winter conditions, entail a challenge that has not been thoroughly examined. We therefore examined the individual response of talitroid amphipods (Americorchestia longicornis; Say 1818) to the strong seasonality affecting sandy beaches in Prince Edward Island, Atlantic Canada (46°N). We then experimentally assessed the influence of low temperatures upon amphipod burrowing behavior and stress levels (hemocyanin concentrations), hypothesizing that cold and freezing temperatures prompt drastic behavioral and physiological responses in the amphipods. Biweekly amphipod samples collected over three years (2019–2021) made evident the narrowness of their activity season and its tight correlation with temperature (Spearman’s r = 0.85). While amphipods were abundant above 10 °C, they were very few under 5 °C and none near 0 °C. In the laboratory, amphipods exposed to 10 °C remained at shallow depths in the sand (70% at 0–4 cm of depth). By comparison, amphipods exposed to 5 °C were found at several depths (0–40 cm), while those exposed to 0 °C concentrated (70%) at depths of 16–40 cm. The assessment of stress levels showed that in comparison to amphipods at ambient temperatures, those exposed to freezing conditions exhibited hemocyanin levels 55 and 82% higher after 1 and 2 weeks, respectively. Combined, these results suggest that cold and freezing temperatures shorten the season of the amphipods and prompt them to burrow deeper into the sand and increase their stress levels, possibly influencing other life history traits.Natural Sciences and Engineering Research Council Canada (NSERC
Assessing the potential impacts of climate change on current coastal ecosystems—A Canadian case study
No full textUnderstanding how climate change affects coastal ecosystems is one of the most important elements in determining vulnerability and resilience for long-term ecosystem management in the face of the increasing risk of coastal hazards (e.g., sea level rise, coastal flooding, and storm surge). This research attempts to undertake a study on the ecosystem–climate nexus in the Canadian province of Prince Edward Island (PEI). Cloud-based remote sensing techniques with Google Earth Engine (GGE) are utilized to identify ecosystem changes over time. In addition, the effects of coastal flooding and storm surge ecosystems under different climate scenarios are examined. The results suggest a reduction in the forest (3%), open water or marsh component (9%), salt water (5%), no open water or marsh component (3%), and salt or brackish marsh (17%) ecosystems from 2013 to 2022. Dune and beach exhibit a non-uniform distribution across the period because of variations in natural processes, with an upward trend ranging from 0% to 11%. Approximately 257 km2 (9.4%) of PEI’s ecosystems would be affected by extreme coastal flooding (scenario 4), compared to 142 km2 (5.2%), 155 km2 (5.7%), and 191 km2 (7%) in scenarios 1, 2, and 3, respectively. Under a 4 m storm surge scenario, around 223 km2 (8.2%) of PEI’s ecosystems would be flooded, compared to 61 km2 (2.2%), 113 km2 (4.1%), and 168 km2 (6.1%) under 1 m, 2 m, and 3 m scenarios, respectively. The findings from this research would enable policymakers to take necessary actions to sustain ecosystem services in PEI while confronting the impacts of climate change
Phylogenetic assessment of Apophallines (Digenea: Opisthorchiidae) with revision of Apophallus donicus Skrjabin & Lindtrop, 1919 complex and some taxonomic propositions
No full textAccording to the current taxonomic concept, the Аpophallinae Ciurea, Citation1924 is a monotypic subfamily of the Opisthorchiidae that comprises species with a median permanent ventrogenital sac containing a well-developed ventral sucker and two gonotyls. A recently formulated molecular hypothesis suggests polyphyly of this subfamily and the presence of two sibling species within one of the nominal species A. donicus Skrjabin & Lindrop, Citation1919. In this paper, we redescribed A. donicus s. str. and renamed A. donicus auct. non Skrjabin & Lindrop, Citation1919 to A. lari (Leonov, Citation1957) based on morphological, biological and molecular (mitochondrial cox1 gene fragments) data. The main morphological differences between species are the length of the distance between the anterior end of the body and the anterior extremity of the vitellarium as a ratio to the forebody length, and the shape of the anterior vitelline follicles. We also aimed to test the monophyly of the Аpophallinae through nuclear-ribosomal molecular markers 18S + 28S rDNA. Tree topology showed Apophallus zalophi (Price, Citation1932) clustered closer to Liliatrema Gubanov, 1953 than to the other Apophallus spp. As a result, we resurrect the genus Pricetrema Ciurea, Citation1933 that earlier was proposed for A. zalophi and abolish the Liliatrematinae Gubanov, 1953 with removal of Liliatrema into the Apophallinae. Thus, according to the updated concept, the Apophallinae contains three genera, Apophallus Lühe, 1909, Liliatrema and Pricetrema, two of which (Apophallus, Pricetrema) have the ventrogenital sac with two gonotyls and one (Liliatrema) has a genital sac without gonotyls
Recent advances in the synthesis and application of magnetic biochar for wastewater treatment
No full textMagnetic biochar (MBC) is a novel bio-carbon material with both desired properties as adsorbent and magnetic characteristics. This review provides an up-to-date summary and discussion on the latest development of MBC, which covers the progress on its synthesis, application, and techno-economic analysis. The review indicates that the direct hydrothermal synthesis has been catching more research attention to produce MBC due to its mild reaction conditions. Instead of the Fe-loaded MBC, there is a trend of using Mn for the magnetization. For the MBC application, how to improve its adsorption performance for water decontamination, ideally to match that of the biochar (BC) or activated carbon, is important. In addition, more studies on the environmental impacts of MBC and life-cycle assessment decoding the process optimization options are necessary. This review will provide valuable references for the development of MBC and MBC-based materials for wastewater treatment
Listeria monocytogenes cholangiohepatitis in a lactating Holstein cow
No full textOBJECTIVE
To describe a unique presentation of systemic Listeria monocytogenes infection in a lactating adult Holstein cow.
ANIMAL
3-year-old second-parity female Holstein, 200 days in milk.
CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES
A 3-year-old Holstein dairy cow was presented for decreased appetite, decreased milk production, and pyrexia. Blood work displayed marked abnormalities in liver-associated parameters. A diagnosis of L monocytogenes cholangiohepatitis was made following liver biopsy, histopathology, and bacterial culture.
TREATMENT AND OUTCOME
The cow was treated with systemic antimicrobial and antipyretic therapy. The cow was discharged to continue treatment on farm, and at time of last communication with the owner, the cow was doing very well, with full resolution of clinical signs.
CLINICAL RELEVANCE
This case report describes a novel presentation of L monocytogenes infection in an adult bovine. L monocytogenes cholangiohepatitis should be considered a rare differential diagnosis in cattle presenting with evidence of pyrexia and liver disease
Numerical modeling and simulation of non-invasive acupuncture therapy utilizing near-infrared light-emitting diode
No full textAcupuncture is one of the most extensively used complementary and alternative medicine therapies worldwide. In this study, we explore the use of near-infrared light-emitting diodes (LEDs) to provide acupuncture-like physical stimulus to the skin tissue, but in a completely non-invasive way. A computational modeling framework has been developed to investigate the light-tissue interaction within a three-dimensional multi-layer model of skin tissue. Finite element-based analysis has been conducted, to obtain the spatiotemporal temperature distribution within the skin tissue, by solving Pennes’ bioheat transfer equation, coupled with the Beer-Lambert law. The irradiation profile of the LED has been experimentally characterized and imposed in the numerical model. The experimental validation of the developed model has been conducted through comparing the numerical model predictions with those obtained experimentally on the agar phantom. The effects of the LED power, treatment duration, LED distance from the skin surface, and usage of multiple LEDs on the temperature distribution attained within the skin tissue have been systematically investigated, highlighting the safe operating power of the selected LEDs. The presented information about the spatiotemporal temperature distribution, and critical factors affecting it, would assist in better optimizing the desired thermal dosage, thereby enabling a safe and effective LED-based photothermal therapy.National Research Council (NRC) Canad
Zebrafish ambra1b knockout reveals a novel role for Ambra1 in primordial germ cells survival, sex differentiation and reproduction
No full textBackground
AMBRA1 is an intrinsically disordered protein, working as a scaffold molecule to coordinate, by protein-protein interaction, many cellular processes, including autophagy, mitophagy, apoptosis and cell cycle progression. The zebrafish genome contains two ambra1 paralogous genes (a and b), both involved in development and expressed at high levels in the gonads. Characterization of the zebrafish paralogous genes mutant lines generated by CRISPR/Cas9 approach showed that ambra1b knockout leads to an all-male population.
Results
We demonstrated that the silencing of the ambra1b gene determines a reduction of primordial germ cells (PGCs), a condition that, in the zebrafish, leads to the development of all-male progeny. PGC reduction was confirmed by knockdown experiments and rescued by injection of ambra1b and human AMBRA1 mRNAs, but not ambra1a mRNA. Moreover, PGC loss was not rescued by injection with human AMBRA1 mRNA mutated in the CUL4-DDB1 binding region, thus suggesting that interaction with this complex is involved in PGC protection from loss. Results from zebrafish embryos injected with murine Stat3 mRNA and stat3 morpholino suggest that Ambra1b could indirectly regulate this protein through CUL4-DDB1 interaction. According to this, Ambra1+/− mice showed a reduced Stat3 expression in the ovary together with a low number of antral follicles and an increase of atretic follicles, indicating a function of Ambra1 in the ovary of mammals as well. Moreover, in agreement with the high expression of these genes in the testis and ovary, we found significant impairment of the reproductive process and pathological alterations, including tumors, mainly limited to the gonads.
Conclusions
By exploiting ambra1a and ambra1b knockout zebrafish lines, we prove the sub-functionalization between the two paralogous zebrafish genes and uncover a novel function of Ambra1 in the protection from excessive PGC loss, which seems to require binding with the CUL4-DDB1 complex. Both genes seem to play a role in the regulation of reproductive physiology.Fondazione TelethonUniversità degli Studi di Padova‘‘Associazione Italiana per la Ricerca sul Cancro’’Italian Ministry of HealthCureSearch for Children’s Cance
Intramammary and systemic use of antimicrobials and their association with resistance in generic Escherichia coli recovered from fecal samples from Canadian dairy herds: A cross-sectional study
No full textAntimicrobial resistance (AMR) in animals, including dairy cattle, is a significant concern for animal and public health worldwide. In this study, we used data collected through the Canadian Dairy Network for Antimicrobial Stewardship and Resistance (CaDNetASR) to: (1) describe the proportions of AMR in fecal E. coli, and (2) investigate the relationship between antimicrobial use (AMU) (intramammary and systemic routes, while accounting for confounding by other variables) and AMR/multidrug resistance (MDR – resistance to ≥ 3 antimicrobial classes) in fecal E. coli from Canadian dairy farms. We hypothesized that an increase of the AMU was associated with an increase in AMR in E. coli isolates. A total of 140 dairy farms across five provinces in Canada were included in the study. Fecal samples from pre-weaned calves, post-weaned heifers, lactating cows, and farm manure storage were cultured, and E. coli isolates were identified using MALDI-TOF MS. The minimum inhibitory concentrations (MIC) to 14 antimicrobials were evaluated using a microbroth dilution methodology. AMU was quantified in Defined Course Dose (DCD - the dose for a standardized complete treatment course on a standard size animal) and converted to a rate indicator - DCD/100 animal-years. Of 1134 fecal samples collected, the proportion of samples positive for E. coli in 2019 and 2020 was 97.1% (544/560) and 94.4% (542/574), respectively. Overall, 24.5% (266/1086) of the E. coli isolates were resistant to at least one antimicrobial. Resistance towards tetracycline was commonly observed (20.7%), whereas resistance to third-generation cephalosporins, fluoroquinolones, and carbapenems was found in 2.2%, 1.4%, and 0.1% of E. coli isolates, respectively. E. coli isolates resistant to two or ≥ 3 antimicrobial classes (MDR) was 2.7% and 15%, respectively. Two multilevel models were built to explore risk factors associated with AMR with AMU being the main exposure. Systemic AMU was associated with increased E. coli resistance. For an increase in systemic AMU equivalent to its IQR, the odds of resistance to any antimicrobial in the model increased by 18%. Fecal samples from calves had higher odds of being resistant to any antimicrobial when compared to other production ages and farm manure storage. The samples collected in 2020 were less likely to be resistant when compared to samples collected in 2019. Compared to previous studies in dairy cattle in North America, AMR in E. coli was lower
iPSC ‐derived microglia carrying the TREM2 R47H /+ mutation are proinflammatory and promote synapse loss
No full textGenetic findings have highlighted key roles for microglia in the pathology of
neurodegenerative conditions such as Alzheimer's disease (AD). A number of
mutations in the microglial protein triggering receptor expressed on myeloid cells 2
(TREM2) have been associated with increased risk for developing AD, most notably
the R47H/+ substitution. We employed gene editing and stem cell models to gain
insight into the effects of the TREM2 R47H/+ mutation on human-induced pluripotent stem cell-derived microglia. We found transcriptional changes affecting
numerous cellular processes, with R47H/+ cells exhibiting a proinflammatory gene
expression signature. TREM2 R47H/+ also caused impairments in microglial
movement and the uptake of multiple substrates, as well as rendering microglia
hyperresponsive to inflammatory stimuli. We developed an in vitro laser-induced
injury model in neuron–microglia cocultures, finding an impaired injury response
by TREM2 R47H/+ microglia. Furthermore, mouse brains transplanted with
TREM2 R47H/+ microglia exhibited reduced synaptic density, with upregulation
of multiple complement cascade components in TREM2 R47H/+ microglia suggesting inappropriate synaptic pruning as one potential mechanism. These findings
identify a number of potentially detrimental effects of the TREM2 R47H/+ mutation on microglial gene expression and function likely to underlie its association
with AD