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1.
Sci Rep ; 14(1): 11088, 2024 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750079

RESUMEN

Many studies seeking to understand the success of biological invasions focus on species' escape from negative interactions, such as damage from herbivores, pathogens, or predators in their introduced range (enemy release). However, much less work has been done to assess the possibility that introduced species might shed mutualists such as pollinators, seed dispersers, and mycorrhizae when they are transported to a new range. We ran a cross-continental field study and found that plants were being visited by 2.6 times more potential pollinators with 1.8 times greater richness in their native range than in their introduced range. Understanding both the positive and negative consequences of introduction to a new range can help us predict, monitor, and manage future invasion events.


Asunto(s)
Especies Introducidas , Animales , Polinización , Micorrizas/fisiología , Simbiosis , Plantas , Dispersión de Semillas , Ecosistema
2.
Sex Health ; 212024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38408426

RESUMEN

BACKGROUND: When demand for counselling in community-based clinics exceeds capacity, waiting lists are typically formed. Determining allocation priority solely on wait time can overlook client risk factors that can elevate priority. We undertook to rigorously adapt the only existing validated counselling triage tool, to better fit the sexual health setting. METHODS: Sexual health counsellors were surveyed about aspects of client presentations that flagged increased priority. The revised Client Priority Rating Scale (CPRS-R) was created through systematic analysis and decision making, informed by survey results and literature review. Four expert sexual health counsellors independently rated the priority of 14 hypothetical clinical vignettes using the CPRS and CPRS-R. RESULTS: Criterion (concurrent), content and face validity are evidenced in the revised scale. Average interrater agreement was higher on the CPRS-R (28%) than the CPRS (11%); however, this difference was marginal (P =0.06). According to Gwet's Agreement Coefficient (AC) and Krippendorff's Alpha, both the CPRS and the CPRS-R demonstrate comparable interrater reliability, substantial and moderate, respectively. Kendall's W indicates the CPRS yielded higher reliability. However, the difference is not substantial. CONCLUSIONS: The CPRS-R is a triage tool designed for the sexual health counselling setting. This tool has demonstrated criterion, content and face validity, as well as moderate to substantial inter-rater reliability. It can be used in sexual health settings to inform assessments about client priority, along with clinical judgement and peer consultation.


Asunto(s)
Salud Sexual , Humanos , Reproducibilidad de los Resultados , Mejoramiento de la Calidad , Consejo , Consejo Sexual
3.
Proc Biol Sci ; 290(2005): 20231022, 2023 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-37583319

RESUMEN

When a plant is introduced to a new ecosystem it may escape from some of its coevolved herbivores. Reduced herbivore damage, and the ability of introduced plants to allocate resources from defence to growth and reproduction can increase the success of introduced species. This mechanism is known as enemy release and is known to occur in some species and situations, but not in others. Understanding the conditions under which enemy release is most likely to occur is important, as this will help us to identify which species and habitats may be most at risk of invasion. We compared in situ measurements of herbivory on 16 plant species at 12 locations within their native European and introduced Australian ranges to quantify their level of enemy release and understand the relationship between enemy release and time, space and climate. Overall, plants experienced approximately seven times more herbivore damage in their native range than in their introduced range. We found no evidence that enemy release was related to time since introduction, introduced range size, temperature, precipitation, humidity or elevation. From here, we can explore whether traits, such as leaf defences or phylogenetic relatedness to neighbouring plants, are stronger indicators of enemy release across species.


Asunto(s)
Ecosistema , Plantas , Filogenia , Australia , Herbivoria , Especies Introducidas
4.
Aggress Behav ; 49(4): 384-395, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36779451

RESUMEN

Self-control training (SCT) is a method of practicing self-controlled behavior in one domain that enhances self-controlled behavior in additional domains. We investigated whether 4 and 12 weeks of practicing self-control would improve control over aggressive behavior. Relative to the active control group, SCT did not reduce aggression regardless of the training duration. We also did not find supportive evidence to suggest that theoretically relevant variables mediated or moderated the effects of SCT on aggression over time. Bayesian analyses showed greater support for the null hypotheses than the alternative hypothesis. Our experiment casts doubt on the long-term effectiveness of using SCT for reducing reactive aggression. Additional research is necessary to identify the conditions under which SCT is most likely to facilitate control over aggressive behavior.


Asunto(s)
Agresión , Autocontrol , Humanos , Teorema de Bayes
5.
Genome Res ; 2022 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-35760562

RESUMEN

The advent of massively parallel sequencing revealed extensive transcription beyond protein-coding genes, identifying tens of thousands of long noncoding RNAs (lncRNAs). Selected functional examples raised the possibility that lncRNAs, as a class, may maintain broad regulatory roles. Expression of lncRNAs is strongly linked with adjacent protein-coding gene expression, suggesting potential cis-regulatory functions. A more detailed understanding of these regulatory roles may be obtained through careful examination of the precise timing of lncRNA expression relative to adjacent protein-coding genes. Despite the diversity of reported lncRNA regulatory mechanisms, where causal cis-regulatory relationships exist, lncRNA transcription is expected to precede changes in target gene expression. Using a high temporal resolution RNA-seq time course, we profiled the expression dynamics of several thousand lncRNAs and protein-coding genes in synchronized, transitioning human cells. Our findings reveal that lncRNAs are expressed synchronously with adjacent protein-coding genes. Analysis of lipopolysaccharide-activated mouse dendritic cells revealed the same temporal relationship observed in transitioning human cells. Our findings suggest broad-scale cis-regulatory roles for lncRNAs are not common. The strong association between lncRNAs and adjacent genes may instead indicate an origin as transcriptional by-products from active protein-coding gene promoters and enhancers.

6.
J Biol Chem ; 296: 100192, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33334889

RESUMEN

Histone methylation is central to the regulation of eukaryotic transcription. In Saccharomyces cerevisiae, it is controlled by a system of four methyltransferases (Set1p, Set2p, Set5p, and Dot1p) and four demethylases (Jhd1p, Jhd2p, Rph1p, and Gis1p). While the histone targets for these enzymes are well characterized, the connection of the enzymes with the intracellular signaling network and thus their regulation is poorly understood; this also applies to all other eukaryotes. Here we report the detailed characterization of the eight S. cerevisiae enzymes and show that they carry a total of 75 phosphorylation sites, 92 acetylation sites, and two ubiquitination sites. All enzymes are subject to phosphorylation, although demethylases Jhd1p and Jhd2p contained one and five sites respectively, whereas other enzymes carried 14 to 36 sites. Phosphorylation was absent or underrepresented on catalytic and other domains but strongly enriched for regions of disorder on methyltransferases, suggesting a role in the modulation of protein-protein interactions. Through mutagenesis studies, we show that phosphosites within the acidic and disordered N-terminus of Set2p affect H3K36 methylation levels in vivo, illustrating the functional importance of such sites. While most kinases upstream of the yeast histone methylation enzymes remain unknown, we model the possible connections between the cellular signaling network and the histone-based gene regulatory system and propose an integrated regulatory structure. Our results provide a foundation for future, detailed exploration of the role of specific kinases and phosphosites in the regulation of histone methylation.


Asunto(s)
Histona Metiltransferasas/metabolismo , Histonas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Metilación , Fosforilación , Procesamiento Proteico-Postraduccional
7.
Sci Rep ; 10(1): 12645, 2020 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-32724137

RESUMEN

Humpback whales endure several months of fasting while undertaking one of the longest annual migrations of any mammal, which depletes the whales' energy stores and likely compromises their physiological state. Airway microbiota are linked to respiratory health in mammals. To illuminate the dynamics of airway microbiota in a physiologically challenged mammal, we investigated the bacterial communities in the blow of East Australian humpback whales at two stages of their migration: at the beginning (n = 20) and several months into their migration (n = 20), using barcoded tag sequencing of the bacterial 16S rRNA gene. We show that early in the fasting the whale blow samples had a higher diversity and richness combined with a larger number of core taxa and a different bacterial composition than later in the fasting. This study provides some evidence that the rich blow microbiota at the beginning of their fasting might reflect the whales' uncompromised physiology and that changes in the microbiota occur during the whales' migration.


Asunto(s)
Migración Animal , Bacterias/aislamiento & purificación , Biodiversidad , Ayuno , Yubarta/microbiología , Sistema Respiratorio/microbiología , Animales , Australia , Bacterias/clasificación , Bacterias/genética , Metabolismo Energético , Conducta Alimentaria , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética , Estaciones del Año
8.
Ecol Evol ; 10(12): 5451-5463, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32607166

RESUMEN

The enemy release hypothesis is often cited as a potential explanation for the success of introduced plants; yet, empirical evidence for enemy release is mixed. We aimed to quantify changes in herbivory and defense in introduced plants while controlling for three factors that might have confounded past studies: using a wide native range for comparison with the introduced range, measuring defense traits without determining whether they affect herbivore preferences, and not considering the effect of time since introduction. The first hypothesis we tested was that introduced plants will have evolved lower levels of plant defense compared to their source population. We grew South African (source) and Australian (introduced) beach daisies (Arctotheca populifolia) in a common-environment glasshouse experiment and measured seven defense traits. Introduced plants had more ash, alkaloids, and leaf hairs than source plants, but were also less tough, with a lower C:N ratio and less phenolics. Overall, we found no difference in defense between source and introduced plants. To determine whether the feeding habits of herbivores align with changes in defense traits, we conducted preference feeding trials using five different herbivore species. Herbivores showed no overall preference for leaves from either group. The second hypothesis we tested was that herbivory on introduced plant species will increase through time after introduction to a new range. We recorded leaf damage on herbarium specimens of seven species introduced to eastern Australia and three native control species. We found no change in the overall level of herbivory experienced by introduced plants since arriving in Australia. CONCLUSION: In the field of invasion ecology, we need to rethink the paradigm that species introduced to a new range undergo simple decreases in defenses against herbivores. Instead, plants are likely to employ a range of defense traits that evolve in both coordinated and opposing ways in response to a plethora of different biotic and abiotic selective pressures.

9.
Environ Microbiol Rep ; 12(3): 324-333, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32162479

RESUMEN

The number of social contacts of mammals is positively correlated with the diversity of their gut microbes. There is some evidence that sociality also affects microbes in the respiratory tract. We tested whether the airway microbiota of cetacean species differ depending on the whales' level of sociality. We sampled the blow of blue (Balaenoptera musculus), grey (Eschrichtius robustus), humpback (Megaptera novaeangliae) and long-finned pilot whales (PWs) (Globicephala melas) and analysed the blow microbiota by barcode tag sequencing targeting the V4 region of the bacterial 16S rRNA gene. Humpback whales (HWs) show higher levels of sociality than blue (BW) and grey (GW), while PWs are the most gregarious among the four species. The blow samples of the HWs showed the highest richness and diversity. HWs were also the only species with a species-specific clustering of their microbial community composition and a relatively large number of core taxa. Therefore, we conclude that it cannot be sociality alone shaping the diversity and composition of airway microbiota. We suggest the whale species' lung volume and size of the plume of exhaled air as an additional factor impacting the transmission potential of blow microbiota from one individual whale to another.


Asunto(s)
Cetáceos/microbiología , Sistema Respiratorio/microbiología , Conducta Social , Animales , Balaenoptera/microbiología , Microbioma Gastrointestinal , Yubarta/microbiología , Ballenas/microbiología , Calderón/microbiología
10.
Astrobiology ; 19(9): 1103-1116, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31173507

RESUMEN

Astrobiology is an ideal context to engage students with the processes of science. However, there is a problem in measuring the effectiveness of engaging students with astrobiology where the learning outcome is aimed at improving student views of science. Most studies suggest little to no change in students' views of science, especially in short experiences of hours or days. These studies mostly use quantitative methods, such as numerical scores derived from survey rating scales and responses. We propose that hidden in those figures, the words of students in written survey responses are telling us about the effectiveness of astrobiology outreach at improving understanding of science. We sampled 483 students from multiple high schools involved in an established astrobiology outreach program in Australia, using pre- and postintervention data collected from an open- and closed-form survey to identify the impacts of the program on students' views of science. We applied both conventional quantitative score analysis methods and computer-based qualitative analysis methods-NVivo and Linguistic Inquiry and Word Count (LIWC) programs. While there was little difference in postsurvey scores, there is evidence in the qualitative data that the astrobiology program creates cognitive conflict in students, a trigger to the learning process that can open students to the first steps in understanding the creative, subjective, and tentative nature of science.


Asunto(s)
Exobiología/educación , Estudiantes , Lingüística , Psicometría , Ciencia , Encuestas y Cuestionarios
11.
J Paediatr Child Health ; 55(9): 1056-1062, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30565355

RESUMEN

AIM: To determine patient/carer expectations of continuous glucose monitoring (CGM) and short-term satisfaction, to assess the efficacy of CGM in improving: fear of hypoglycaemia and glycaemic control (HbA1c , ketosis, hypoglycaemia) and to determine time requirements of diabetes clinic staff in commencing and administering CGM. METHODS: We assessed CGM-naïve patients starting on CGM at a Sydney Diabetes Centre following the introduction of a nationwide government subsidy for CGM. A standardised questionnaire was administered collecting demographic and glycaemic information in addition to Likert scale assessment of expectations and satisfaction. Clinic staff reported time dedicated to CGM education, commencement and follow-up. RESULTS: A total of 55 patients or parents/carers completed baseline questionnaires, with 37 completing a 3-month follow-up questionnaire. There were high expectations of CGM prior to commencement and high satisfaction ratings on follow-up. CGM improved fear of hypoglycaemia, and total daily insulin dose increased after commencement of CGM. There was a trend towards lower HbA1c that was not statistically significant and no statistically significant reduction in ketosis or hypoglycaemia. Comments were mostly positive, with some concern raised regarding technical issues and a lack of subsidy after 21 years of age. Staff time requirements were substantial, with an estimated average of 7.7 h per patient per year. CONCLUSIONS: Patients and families have high expectations of CGM, and satisfaction levels are high in the short term. Total insulin delivery increased after CGM commencement. Time requirements by staff are substantial but are worthwhile if families' overall satisfaction levels are high.


Asunto(s)
Automonitorización de la Glucosa Sanguínea , Diabetes Mellitus Tipo 1 , Programas de Gobierno , Adolescente , Atención Ambulatoria , Niño , Miedo , Femenino , Humanos , Hipoglucemia/psicología , Sistemas de Infusión de Insulina , Masculino , Nueva Gales del Sur , Satisfacción del Paciente , Encuestas y Cuestionarios , Adulto Joven
12.
PLoS One ; 8(11): e81196, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24260558

RESUMEN

Nanomechanical testing methods that are suitable for a range of hydrated tissues are crucial for understanding biological systems. Nanoindentation of tissues can provide valuable insights into biology, tissue engineering and biomimetic design. However, testing hydrated biological samples still remains a significant challenge. Shark jaw cartilage is an ideal substrate for developing a method to test hydrated tissues because it is a unique heterogeneous composite of both mineralized (hard) and non-mineralized (soft) layers and possesses a jaw geometry that is challenging to test mechanically. The aim of this study is to develop a novel method for obtaining multidirectional nanomechanical properties for both layers of jaw cartilage from a single sample, taken from the great white shark (Carcharodon carcharias). A method for obtaining multidirectional data from a single sample is necessary for examining tissue mechanics in this shark because it is a protected species and hence samples may be difficult to obtain. Results show that this method maintains hydration of samples that would otherwise rapidly dehydrate. Our study is the first analysis of nanomechanical properties of great white shark jaw cartilage. Variation in nanomechanical properties were detected in different orthogonal directions for both layers of jaw cartilage in this species. The data further suggest that the mineralized layer of shark jaw cartilage is less stiff than previously posited. Our method allows multidirectional nanomechanical properties to be obtained from a single, small, hydrated heterogeneous sample. Our technique is therefore suitable for use when specimens are rare, valuable or limited in quantity, such as samples obtained from endangered species or pathological tissues. We also outline a method for tip-to-optic calibration that facilitates nanoindentation of soft biological tissues. Our technique may help address the critical need for a nanomechanical testing method that is applicable to a variety of hydrated biological materials whether soft or hard.


Asunto(s)
Cartílago/química , Maxilares/química , Ensayo de Materiales/métodos , Tiburones/anatomía & histología , Agua/química , Animales , Fenómenos Biomecánicos , Calibración , Cartílago/anatomía & histología , Módulo de Elasticidad , Especies en Peligro de Extinción , Dureza , Maxilares/anatomía & histología , Masculino , Ensayo de Materiales/instrumentación , Tiburones/fisiología , Ingeniería de Tejidos
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