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Building IPECP into community health promotion
(Health and Medical Publishing Group, 2024-07-01) Abdoola, Shabnam Salim; Milton, Carmen; shabnam.abdoola@up.ac.za
Due to its culturally and linguistically diverse society, high prevalence of communication disorders, resource limitations, and fragmented healthcare services, South Africa (SA) needs to integrate interprofessional education and collaborative practice (IPECP) into community health promotion. IPECP in health professions education is necessary in preparing ‘collaborative practice-ready’ health care professionals who are socially accountable and prepared to respond to local health needs. Integrating IPECP strategies into existing curricula and placing interprofessional students at the same clinical sites can promote collaborative education and practice. Providing students with interprofessional clinical practice experience provides real world experience and insight, while enhancing an understanding and respect for other professionals.
Self-growth suppression in Bradyrhizobium diazoefficiens is caused by a diffusible antagonist
(Oxford University Press, 2025-03) Sandhu, Armaan Kaur; Fischer, Brady R.; Subramanian, Senthil; Hoppe, Adam D.; Brözel, Volker Siegfried
Microbes in soil navigate interactions by recognizing kin, forming social groups, exhibiting antagonistic behavior, and engaging in competitive kin rivalry. Here, we investigated a novel phenomenon of self-growth suppression (sibling rivalry) observed in Bradyrhizobium diazoefficiens USDA 110. Swimming colonies of USDA 110 developed a distinct demarcation line and inter-colony zone when inoculated adjacent to each other. In addition to self, USDA 110 suppressed growth of other Bradyrhizobium strains and several other soil bacteria. We demonstrated that the phenomenon of sibling rivalry is due to growth suppression but not cell death. The cells in the inter-colony zone were culturable but had reduced respiratory activity, ATP levels, and motility. The observed growth suppression was due to the presence of a diffusible effector compound. This effector was labile, preventing extraction, and identification, but it is unlikely a protein or a strong acid or base. This counterintuitive phenomenon of self-growth suppression suggests a strategic adaptation for conserving energy and resources in competitive soil environments. Bradyrhizobium’s utilization of antagonism including self-growth suppression likely provides a competitive advantage for long-term success in soil ecosystems.
Bradyrhizobium diazoefficiens cultures display phenotypic heterogeneity
(Oxford University Press, 2025-03) Sarao, Sukhvir K.; Sandhu, Armaan K.; Hanson, Ryan L.; Govil, Tanvi; Brözel, Volker Siegfried
Bacteria growing in liquid culture are assumed to be homogenous in phenotype. Characterization of individual cells shows that some clonal cultures contain more than one phenotype. Bacteria appear to employ bet hedging where various phenotypes help the species survive in diverse niches in soil and rhizosphere environments. We asked whether the agriculturally significant bacterium Bradyrhizobium diazoefficiens USDA 110, which fixes nitrogen with soybean plants, displays phenotypic heterogeneity when grown under laboratory conditions. We observed differential binding of sugar-specific lectins in isogenic populations, revealing differential surface properties. We employed Percoll™ density gradient centrifugation to separate clonal populations of exponential and stationary phase B. diazoefficiens into four fractions and characterized their phenotype by proteomics. Specific phenotypes were then characterized in detail. Fractions varied by cell size, polyhydroxyalkanoate content, lectin binding profile, growth rate, cellular adenosine triphosphate, chemotaxis, and respiration activity. Phenotypes were not heritable because the specific buoyant densities of fractions equilibrated within 10 generations. We propose that heterogeneity helps slow growing B. diazoefficiens proliferate and maintain populations in the different environments in soil and the rhizosphere.
DPANN symbiont of Haloferax volcanii accelerates xylan degradation by the non-host haloarchaeon Halorhabdus sp.
(Elsevier, 2025-02-21) Reva, Oleg N.; La Cono, Violetta; Marturano, Laura; Crisafi, Francesca; Smedile, Francesco; Mudaliyar, Manasi; Ghosal, Debnath; Selivanova, Elena A.; Ignatenko, Marina E.; Ferrer, Manuel; Fernandez-Lopez, Laura; Krupovic, Mart; Yakimov, Michail M.; oleg.reva@up.ac.za
This study examines a natural consortium of halophilic archaea, comprising xylan-degrading Halorhabdus sp. SVX81, consortium cohabitant Haloferax volcanii SVX82 (formerly H. lucentense SVX82), and its DPANN ectosymbiont Ca. Nanohalococcus occultus SVXNc. Transcriptomics and targeted metabolomics demonstrated that the tripartite consortium outperformed individual and the Halorhabdus sp. SVX81 with H. volcanii SVX82 bipartite cultures in xylan degradation, exhibiting a division of labor: the DPANN symbiont processed glycolysis products, while other members performed xylan depolymerization and biosynthesis of essential compounds. Electron microscopy and cryo-electron tomography revealed the formation of heterocellular biofilms interlinked by DPANN cells. The findings demonstrated that DPANN symbionts can interact directly with other members of microbial communities, which are not their primary hosts, influencing their gene expression. However, DPANN proliferation requires their primary host presence. The study highlights the collective contribution of consortium members to xylan degradation and their potential for biotechnological applications in the management of hypersaline environments.
Segment reduction-based SVPWM applied three-level F-type inverter for power quality conditioning in an EV proliferated distributed system
(Wiley, 2025-02) Madhavan, Meenakshi; N., Chellammal; Bansal, Ramesh C.
The objective of this paper lies in the realization of a three-level F-type inverter (3L-FTI) as a shunt active filter in an EV-proliferated environment. The switches are triggered using segment reduced space vector pulse width modulation (SVPWM). This modulation technique provides a lower number of switching transitions than existing PWM strategies. Consequently, the inverter switches experience a decrease in both switching stress and switching losses. A 3L-FTI is a diode-free structure that reduces the harmonics in the source current with a high power factor (PF), where instantaneous reactive power (IRPT) theory is employed to generate the reference currents from the utility grid. In contrast to traditional three-level inverters, two-thirds of switches in 3L-FTI can tolerate a voltage stress equal to half of the DC input voltage. While studying the behaviour of this shunt active filter, with three different nonlinear loading conditions, the current total harmonic distortion (THD) is reduced from 28.43% to 2.13% after compensation, which is under 5% of IEEE standard 519-2014. Therefore, the 3L-FTI controlled by segment reduction SVPWM can be considered as better candidate for active filter in an EV proliferated distribution system.