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Fatal toxoplasmosis in Little Penguins (Eudyptula minor) from Penguin Island, Western Australia
Routine post mortems of deceased penguins from Penguin Island, Western Australia, found that a temporal cluster of cases presented with characteristic gross and microscopic changes, namely birds in good body condition with hepatomegaly and splenomegaly, multifocal hepatic and splenic necrosis and numerous, 1–2 μm diameter protozoan parasites within the necrotic foci.
Electron microscopy identified the protozoa as belonging to the phylum Apicomplexa. Molecular investigations by PCR gave inconsistent results. PCR performed by an external laboratory identified a novel Haemoproteus spp. organism in samples from 4 of 10 cases from this group, while PCR at Murdoch University identified Toxoplasma gondii in 12 of 13 cases (including 9 of the 10 assayed at the external laboratory). Immunohistochemistry of formalin fixed tissues also identified Toxoplasma in the hepatic and splenic lesions.
The distinctive mortalities which were observed in this group of penguins are attributed to a fulminant toxoplasmosis, with a concurrent Haemoproteus infection in some cases. Though the clinical signs of infection are unknown, the gross and microscopic appearance at post mortem is sufficiently characteristic to allow a diagnosis to be made on these features. Definitive confirmation of Toxoplasma infection can be made by immunohistochemistry or PCR
The cannabinoid profile and growth of hemp (Cannabis sativa L.) is influenced by tropical daylengths and temperatures, genotype and nitrogen nutrition
Hemp (Cannabis sativa L.) has regained worldwide interest as a crop across temperate and subtropical regions. However, there is a paucity of information about the responses of hemp to environmental conditions and interactions between genotype and environment. This study compared the growth responses of a temperate hemp variety (Morphet Late) and three tropical/subtropical varieties (ECO-GH15, ECO-MC16 and ECO-YP16) to tropical daylengths (11.5 h and 12.5 h), temperatures and varying nitrogen (0, 50, 100, 150 kg ha-1 of N) rates. Three experiments under controlled environmental conditions were conducted to test the growth, and cannabinoid production responses to N. Analysis of phenological data revealed significantly different responses between varieties in terms of days to emergence, time to flowering, growth patterns and final biomass showing predominant responses to daylength or temperature depending on the variety. Two tropical/subtropical varieties (ECO-GH15, ECO-MC16) responded similarly under all conditions; the other (ECO-YP16) showed a marked response to temperature rather than daylength, although all varieties had a strong biomass response to N increase. For all varieties, except the temperate variety, the concentration of Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), and some minor cannabinoids were significantly increased by a one-hour daylength increase. This study highlights the importance of temperature, daylength, and nitrogen for growth, time to flowering, and cannabinoid concentrations of different hemp varieties grown under tropical conditions and shows the importance of selecting low THC varieties for production in tropical/subtropical environments
Discovery of major quantitative trait loci and candidate genes for fresh seed dormancy in groundnut
Spanish bunch groundnut varieties occupy most of the cultivated area in Asia and Africa, and these varieties lack required 2-3 weeks of fresh seed dormancy (FSD) hampering kernel quality. Genomic breeding can help to improve commercial groundnut cultivars for FSD in a shorter time with greater precision. In this regard, a recombinant inbred line (RIL) population from the cross ICGV 02266 (non-dormant) × ICGV 97045 (dormant) was developed and genotyped with a 5 K mid-density genotyping assay. A linkage map was constructed with 325 SNP loci spanning a total map length of 2335.3 cM and five major QTLs were identified on chromosomes Ah01, Ah11, Ah06, Ah16 and Ah17. Based on differential gene expression using transcriptomic information from dormant (Tifrunner) and non-dormant (ICGV 91114) genotypes, histone deacetylases, histone-lysine N-methyltransferase, cytochrome P450, protein kinases, and ethylene-responsive transcription factor were identified as key regulators involved in the hormonal regulation of dormancy. Six Kompetitive Allele Specific PCR (KASP) markers were successfully validated in the diverse panel including selected RILs of the same population and germplasm lines. These validated KASP markers could facilitate faster breeding of new varieties with desired dormancy using marker-assisted early generation selection
Carbon mineralization in subtropical alluvial arable soils amended with sugarcane bagasse and rice husk biochars
Subtropical recent alluvial soils are low in organic carbon (C). Thus, increasing organic C is a major challenge to sustain soil fertility. Biochar amendment could be an option as biochar is a C-rich pyrolyzed material, which is slowly decomposed in soil. We investigated C mineralization (CO2-C evolution) in two types of soils (recent and old alluvial soils) amended with two feedstocks (sugarcane bagasse and rice husk) (1%, weight/weight), as well as their biochars and aged biochars under a controlled environment (25 ± 2 °C) over 85 d. For the recent alluvial soil (charland soil), the highest absolute cumulative CO2-C evolution was observed in the sugarcane bagasse treatment (1 140 mg CO2-C kg-1 soil) followed by the rice husk treatment (1 090 mg CO2-C kg-1 soil); the lowest amount (150 mg CO2-C kg-1 soil) was observed in the aged rice husk biochar treatment. Similarly, for the old alluvial soil (farmland soil), the highest absolute cumulative CO2-C evolution (1 290 mg CO2-C kg-1 soil) was observed in the sugarcane bagasse treatment and then in the rice husk treatment (1 270 mg CO2-C kg-1 soil); the lowest amount (200 mg CO2-C kg-1 soil) was in the aged rice husk biochar treatment. Aged sugarcane bagasse and rice husk biochar treatments reduced absolute cumulative CO2-C evolution by 10% and 36%, respectively, compared with unamended recent alluvial soil, and by 10% and 18%, respectively, compared with unamended old alluvial soil. Both absolute and normalized C mineralization were similar between the sugarcane bagasse and rice husk treatments, between the biochar treatments, and between the aged biochar treatments. In both soils, the feedstock treatments resulted in the highest cumulative CO2-C evolution, followed by the biochar treatments and then the aged biochar treatments. The absolute and normalized CO2-C evolution and the mineralization rate constant of the stable C pool (Ks) were lower in the recent alluvial soil compared with those in the old alluvial soil. The biochars and aged biochars had a negative priming effect in both soils, but the effect was more prominent in the recent alluvial soil. These results would have good implications for improving organic matter content in organic C-poor alluvial soils
Treatment of wastewater from biomass pyrolysis and recovery of its organic compounds with char-assisted drying
This study proposes a new process that treats pyrolytic wastewater (PWW) from biomass pyrolysis with char-assisted drying. It can be operated at two modes: (I) one-stage drying for PWW treatment; and (II) two-stage drying and condensation for both treating PWW and recovering valuable chemicals (e.g., acetic acid). The process is proved via drying the mixture of a char and a synthetic PWW solution containing acetic acid, acetol, furfural, and phenol at different temperatures (60, 80, and 105 °C) and char-to-PWW mass ratios (1.0, 1.5, and 2.0). The results, supported by density functional theory (DFT) calculations, demonstrate that under Mode I, the char captures over 97.1% of the organic compounds in the PWW at 60 °C and a char-to-PWW ratio of 2.0, while evaporating almost all the water. The evaporated stream can be potentially discharged into the atmosphere without condensation or condensed into wastewater with a significantly reduced content of total organic carbon. Under Mode II, the char-PWW mixture is sequentially dried at 60 and 105 °C, with the exhaust gases being separately condensed. This yields a stream of purified acetic acid solution (concentration: ∼76 wt%) concentrated by a factor of ∼6.3 (compared with the PWW), with a recovery rate of ∼29%
Comparison between continuous and daytime mixing for the treatment of raw anaerobically digested abattoir effluent (ADAE) and microalgae production in open raceway ponds
This study investigated the outdoor cultivation of two local microalgae species (Chlorella sp. and Scenedesmus sp.) in raw anaerobically digested abattoir effluent (ADAE) which were subjected to both continuous (24 h) and daytime only (12 h) paddle wheel mixing. The goal of this study was to identify the most efficient microalgae species and mixing condition for raw ADAE bioremediation. No differences in Chlorella sp. biomass productivity were recorded for both mixing conditions while values were higher (14%) for 24 h mixed Scenedesmus sp. Despite the exhaustion of ammoniacal nitrogen (NH3-N) in all treatments, only between 14 and 28% of NH3-N was assimilated for biomass production. Microalgae growth in ADAE significantly reduced the total aerobic bacteria population and eliminated Escherichia coli content in ADAE for all treatments. Overall, Scenedesmus sp. demonstrated higher biomass productivity and nutrient removal efficiency in ADAE when compared to Chlorella sp., with the continuously (24 h) mixed cultures being most efficient
Environmental effects of stratospheric ozone depletion, UV radiation, and interactions with climate change: UNEP Environmental Effects Assessment Panel, Update 2021
The Environmental Effects Assessment Panel of the Montreal Protocol under the United Nations Environment Programme evaluates effects on the environment and human health that arise from changes in the stratospheric ozone layer and concomitant variations in ultraviolet (UV) radiation at the Earth’s surface. The current update is based on scientific advances that have accumulated since our last assessment (Photochem and Photobiol Sci 20(1):1–67, 2021). We also discuss how climate change affects stratospheric ozone depletion and ultraviolet radiation, and how stratospheric ozone depletion affects climate change. The resulting interlinking effects of stratospheric ozone depletion, UV radiation, and climate change are assessed in terms of air quality, carbon sinks, ecosystems, human health, and natural and synthetic materials. We further highlight potential impacts on the biosphere from extreme climate events that are occurring with increasing frequency as a consequence of climate change. These and other interactive effects are examined with respect to the benefits that the Montreal Protocol and its Amendments are providing to life on Earth by controlling the production of various substances that contribute to both stratospheric ozone depletion and climate change
Eyeblink rate, a putative dopamine marker, predicts negative reinforcement learning by tDCS of the dlPFC
Studies have shown that anodal transcranial direct current stimulation (tDCS) applied to the dorsolateral prefrontal cortex (dlPFC) increases extracellular dopamine (DA) levels in the striatum [1]..
Comparative flower transcriptome network analysis reveals DEGs involved in chickpea reproductive success during salinity
Salinity is increasingly becoming a significant problem for the most important yet intrinsically salt-sensitive grain legume chickpea. Chickpea is extremely sensitive to salinity during the reproductive phase. Therefore, it is essential to understand the molecular mechanisms by comparing the transcriptomic dynamics between the two contrasting genotypes in response to salt stress. Chickpea exhibits considerable genetic variation amongst improved cultivars, which show better yields in saline conditions but still need to be enhanced for sustainable crop production. Based on previous extensive multi-location physiological screening, two identified genotypes, JG11 (salt-tolerant) and ICCV2 (salt-sensitive), were subjected to salt stress to evaluate their phenological and transcriptional responses. RNA-Sequencing is a revolutionary tool that allows for comprehensive transcriptome profiling to identify genes and alleles associated with stress tolerance and sensitivity. After the first flowering, the whole flower from stress-tolerant and sensitive genotypes was collected. A total of ~300 million RNA-Seq reads were sequenced, resulting in 2022 differentially expressed genes (DEGs) in response to salt stress. Genes involved in flowering time such as FLOWERING LOCUS T (FT) and pollen development such as ABORTED MICROSPORES (AMS), rho-GTPase, and pollen-receptor kinase were significantly differentially regulated, suggesting their role in salt tolerance. In addition to this, we identify a suite of essential genes such as MYB proteins, MADS-box, and chloride ion channel genes, which are crucial regulators of transcriptional responses to salinity tolerance. The gene set enrichment analysis and functional annotation of these genes in flower development suggest that they can be potential candidates for chickpea crop improvement for salt tolerance
Computed tomographic, ultrasonographic, MRI and radiographic findings of a venous malformation with phleboliths in the thoracic limb of a dog
An 11-month-old entire male Rottweiler was referred for further investigation of raised, soft, compressible, non-pulsatile, subcutaneous tubular structures along the right antebrachium that had been diagnosed to be a vascular malformation on histopathology of a subcutaneous biopsy. Computed tomographic (CT) with angiography did not reveal an arteriovenous malformation or fistula. Ultrasonography of the limb demonstrated a venous malformation with thrombi and phleboliths. An MRI study of the limb was consistent with a venous malformation with small rounded luminal signal voids that were confirmed to be phleboliths. Radiography at follow-up demonstrated phleboliths. This is the first report describing the combined CT, ultrasonographic, MRI and radiographic characteristics of venous malformation with phleboliths in a limb of a dog