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Metabarcoding reveals southern hemisphere fungal endophytes within wood of cultivated Proteaceae in Portugal
Endophytic fungal hitch-hikers have been difficult to detect in the past, and have potentially spread these latent pathogens via the global plant trade. The African genera Protea, Leucospermum and Leucadendron, commercially referred to as proteas, form the basis of a global flower production industry. The largest producers of proteas are Australia and South Africa, followed by Portugal and Spain. In the 1990s propagation material from South Africa was used to establish protea orchards in Portugal. We utilized metabarcoding to determine if this plant trade has carried host-specific fungal pathogens to a new environment. Wood samples collected from asymtomatic twigs from Portuguese farms, where propagation material had been imported from South Africa, was compared to material from South African farms that originally produced and supplied rooted and unrooted cuttings. DNA metabarcoding, using fungal-specific primers for the ITS2 gene region, produced 1237 OTUs. Focusing only on known pathogens of protea, we found that the Portuguese orchards contained fungal disease agents associated with Proteaceae or other plant families from the Southern Hemisphere. Our sampling technique could be used by agencies and applied to other plant material and pathogens to reduce the spread of pathogens
Arterial carbon dioxide tension has a non-linear association with survival after out-of-hospital cardiac arrest: A multicentre observational study
Purpose
International guidelines recommend targeting normocapnia in mechanically ventilated out-of-hospital cardiac arrest (OHCA) survivors, but the optimal arterial carbon dioxide (PaCO2) target remains controversial. We hypothesised that the relationship between PaCO2 and survival is non-linear, and targeting an intermediate level of PaCO2 compared to a low or high PaCO2 in the first 24-h of ICU admission is associated with an improved survival to hospital discharge (STHD) and at 12-months.
Methods
We conducted a retrospective multi-centre cohort study of adults with non-traumatic OHCA requiring admission to one of four tertiary hospital intensive care units for mechanical ventilation. A four-knot restricted cubic spline function was used to allow non-linearity between the mean PaCO2 within the first 24 h of ICU admission after OHCA and survival, and optimal PaCO2 cut-points were identified from the spline curve to generate corresponding odds ratios.
Results
We analysed 3769 PaCO2 results within the first 24-h of ICU admission, from 493 patients. PaCO2 and survival had an inverted U-shape association; normocapnia was associated with significantly improved STHD compared to either hypocapnia (45 mmHg) (aOR 0.45, 95% CI 0.24−0.84). Of the twelve predictors assessed, PaCO2 was the third most important predictor, and explained >11% of the variability in survival. The survival benefits of normocapnia extended to 12-months.
Conclusions
Normocapnia within the first 24-h of intensive care admission after OHCA was associated with an improved survival compared to patients with hypocapnia or hypercapnia
Revisiting collaboration within and beyond the school library: New ways of measuring effectiveness
Collaboration in school libraries can be viewed as a supportive and respectful working relationship between participants involved in developing, planning and creating learning opportunities and experiences, as well as to ensure optimal use of the school library resource. While strong collaboration between school library staff and teachers and leadership beyond the school library is a key goal of school libraries, actual levels of collaboration may be lower than desired. There is a paucity of recent research that captures factors relevant to effective collaboration from current and diverse contexts, and limited consideration of how these factors can contribute to measures of effectiveness for school libraries. This article proposes possible measures of effectiveness and a pragmatic research plan that can build the evidence-base for the practice of collaboration both within and beyond the library
Correction to: The global summit on the efficacy and effectiveness of spinal manipulative therapy for the prevention and treatment of non-musculoskeletal disorders: A systematic review of the literature
Correction to: Chiropr Man Therap 19, 348 (2021)
https://doi.org/10.1186/s12998-021-00362-
Control of an IPMC soft actuator using adaptive full-order recursive terminal sliding mode
The ionic polymer metal composite (IPMC) actuator is a kind of soft actuator that can work for underwater applications. However, IPMC actuator control suffers from high nonlinearity due to the existence of inherent creep and hysteresis phenomena. Furthermore, for underwater applications, they are highly exposed to parametric uncertainties and external disturbances due to the inherent characteristics and working environment. Those factors significantly affect the positioning accuracy and reliability of IPMC actuators. Hence, feedback control techniques are vital in the control of IPMC actuators for suppressing the system uncertainty and external disturbance. In this paper, for the first time an adaptive full-order recursive terminal sliding-mode (AFORTSM) controller is proposed for the IPMC actuator to enhance the positioning accuracy and robustness against parametric uncertainties and external disturbances. The proposed controller incorporates an adaptive algorithm with terminal sliding mode method to release the need for any prerequisite bound of the disturbance. In addition, stability analysis proves that it can guarantee the tracking error to converge to zero in finite time in the presence of uncertainty and disturbance. Experiments are carried out on the IPMC actuator to verify the practical effectiveness of the AFORTSM controller in comparison with a conventional nonsingular terminal sliding mode (NTSM) controller in terms of smaller tracking error and faster disturbance rejection
A diagnostic marker kit for Fusarium wilt and sterility mosaic diseases resistance in pigeonpea
Fusarium wilt (FW) and sterility mosaic diseases (SMD) are key biotic constraints to pigeonpea production. Occurrence of these two diseases in congenial conditions is reported to cause complete yield loss in susceptible pigeonpea cultivars. Various studies to elucidate genomic architecture of the two traits have revealed significant marker–trait associations for use in breeding programs. However, these DNA markers could not be used effectively in genomics-assisted breeding for developing FW and SMD resistant varieties primarily due to pathogen variability, location or background specificity, lesser phenotypic variance explained by the reported QTL and cost-inefficiency of the genotyping assays. Therefore, in the present study, a novel approach has been used to develop a diagnostic kit for identification of suitable FW and SMD resistant lines. This kit was developed with 10 markers each for FW and SMD resistance. Investigation of the diversity of these loci has shown the role of different alleles in different resistant genotypes. Two genes (C.cajan_03691 and C.cajan_18888) for FW resistance and four genes (C.cajan_07858, C.cajan_20995, C.cajan_21801 and C.cajan_17341) for SMD resistance have been identified. More importantly, we developed a customized and cost-effective Kompetitive allele-specific PCR genotyping assay for the identified genes in order to encourage their downstream applications in pigeonpea breeding programs. The diagnostic marker kit developed here will offer great strength to pigeonpea varietal development program, since the resistance against these two diseases is essentially required for nominating an improved line in varietal release pipeline
Sigma factor modulation for cyanobacterial metabolic engineering
Sigma (σ) factors are key regulatory proteins that control the transcription initiation in prokaryotes. In response to environmental or developmental cues, σ factors initiate the transcription of necessary genes responsible for maintaining a life-sustaining metabolic balance. Due to the significant role of σ factors in bacterial metabolism, their rational engineering for commercial metabolite production in photoautotrophic, cyanobacterial cells is a desirable venture. As cyanobacterial genomes typically encode multiple σ factors, effective execution of metabolic engineering efforts largely relies on uncovering the complicated gene regulatory network and further characterization of the members of σ factor regulatory circuits. This review outlines the prospects of σ factor in metabolic engineering of cyanobacteria, summarizes the challenges in the path towards an efficient strain construction and highlights the genomic context of putative regulators of cyanobacterial σ factors
Prospective randomized controlled blinded clinical trial evaluating biomarkers of acute kidney injury following 6% hydroxyethyl starch 130/0.4 or Hartmann's solution in dogs
Objective: To evaluate the effect of 6% hydroxyethyl starch (HES) 130/0.4, compared with a Hartmann's solution control (CRYST), on urine biomarkers of acute kidney injury (AKI) in dogs prescribed a fluid bolus.
Design: Randomized, controlled, blinded clinical trial January 2018 to February 2019.
Setting: University teaching hospital.
Animals: Forty client‐owned dogs.
Interventions: Dogs prescribed a fluid bolus were randomized to receive at least 10 mL/kg of HES or CRYST with clinicians and investigators blinded to fluid type. Study fluid was used for further boluses as required in the following 24 hours, to a limit of 40 mL/kg total, after which fluid administration was open‐label.
Measurements and Main Results: Urine was collected prior to and 6, 12, and 24 hours after the first study fluid bolus. Urine concentrations of AKI biomarkers: neutrophil gelatinase‐associated lipocalin (NGAL), cystatin C, kidney injury molecule‐1 (KIM), clusterin, and osteopontin were measured using a magnetic bead multiplexed assay. Osmolality‐indexed biomarker concentrations were compared between groups over time with linear mixed‐effects models, with P < 0.05 considered significant. The mean volume of study fluid administered was not significantly different between groups (HES: 23.1 mL/kg, CRYST: 25.9 mL/kg; P = 0.47, t‐test). There were no significant differences between groups in change over time of osmolality‐indexed urine concentrations of NGAL (P = 0.91), cystatin C (P = 0.95), KIM (P = 0.77), clusterin (P = 0.63), or osteopontin (P = 0.91). The maximum Veterinary Acute Kidney Injury (VAKI) score up to 7 days during hospitalization (P = 1.0) and in‐hospital mortality (P = 0.49) were not significantly different between groups, as compared by Fisher's exact test.
Conclusions: There were no differences in change over time of urine AKI biomarkers in dogs treated with 10 – 40 mL/kg HES or CRYST over 24 hours. Larger clinical trials with patient‐centered outcomes are required to investigate the safety of HES in dogs
Investigating the associations of constructivist beliefs and classroom climate on teachers' self-efficacy among Australian secondary mathematics teachers
This study examines the associations of constructivist beliefs and classroom climate on teachers' self-efficacy in instruction, classroom management, and student engagement among Australian secondary mathematics teachers. To do this, it uses the integrated model of teachers' self-efficacy with the concept of analysis of teaching tasks. The study uses structural equation modeling to analyze data from 495 mathematics teachers in the Teaching and Learning International Survey (TALIS) 2013. The results reveal the integrated model is a valid theoretical framework to explain Australian secondary mathematics teachers' self-efficacy. Teachers' constructivist beliefs and classroom climate are positively and statistically significantly related to teachers' self-efficacy in instruction, classroom management and student engagement. In contrast, constructivist beliefs have no significant correlation with classroom climate