1,726 research outputs found
Recommended from our members
Low temperatures impact species distributions of jumping spiders across a desert elevational cline.
Temperature is known to influence many aspects of organisms and is frequently linked to geographical species distributions. Despite the importance of a broad understanding of an animal's thermal biology, few studies incorporate more than one metric of thermal biology. Here we examined an elevational assemblage of Habronattus jumping spiders to measure different aspects of their thermal biology including thermal limits (CTmin, CTmax), thermal preference, V̇CO2 as proxy for metabolic rate, locomotor behavior and warming tolerance. We used these data to test whether thermal biology helped explain how species were distributed across elevation. Habronattus had high CTmax values, which did not differ among species across the elevational gradient. The highest-elevation species had a lower CTmin than any other species. All species had a strong thermal preference around 37 °C. With respect to performance, one of the middle elevation species was significantly less temperature-sensitive in metabolic rate. Differences between species with respect to locomotion (jump distance) were likely driven by differences in mass, with no differences in thermal performance across elevation. We suggest that Habronattus distributions follow Brett's rule, a rule that predicts more geographical variation in cold tolerance than heat. Additionally, we suggest that physiological tolerances interact with biotic factors, particularly those related to courtship and mate choice to influence species distributions. Habronattus also had very high warming tolerance values (> 20 °C, on average). Taken together, these data suggest that Habronattus are resilient in the face of climate-change related shifts in temperature
Thermodynamic Assessment of Air-Cycles for Ultra-Low-Temperature Refrigerated Container Applications
Countering Islamophobia in the Victorian Population
Islamophobia underpins extremist verbal and physical attacks on Muslim communities. It has become widespread in Australian society, and normalised in everyday settings such as in mainstream media. There is general agreement among Australian researchers and community representatives that the concept of Islamophobia is a useful tool for understanding and developing ways to challenge anti-Islam attitudes. However, despite it becoming widespread, Islamophobia should not be treated as a singular problem as it takes many different forms (see Peucker and Smith 2019), which require targeted responses. This brief provides contemporary empirical insights into the extent of Islamophobia in Victoria, and how it is manifest, in order to help develop policy responses. In November 2019, we undertook an online representative survey of 4019 Victorians to examine Islamophobia in Australia. We asked questions about respondents’ attitudes towards cultural diversity, racial equality and privilege; trust and fairness; Muslims and Islam; and other ethno-cultural groups in Australian society; their experiences of racism and discrimination; their contact with Muslims and knowledge of Islam; their trust of institutions; political affiliation; and support for extreme politics (e.g., violence, non-democratic governance). To our knowledge, this was the largest representative survey undertaken in Victoria with the purpose of measuring Victorians’ perceptions of and attitudes towards Muslims and Islam. Based on respondents’ answers, we used latent class analysis to reveal groups in the Victorian population. Latent class analysis is an advanced statistical method that identifies related sets of responses in a dataset that may be hidden even from trained observers (Hagenaars and McCutcheon 2002; Uebersax 1993; Heinen 1996)
Understanding Varied Attitudes Towards Muslims
The focus of this research was to determine the prevalence and type of Islamophobia in the Victorian population. Islamophobia sentiment feeds the actions of right-wing extremist attacks on Muslim communities. But it has also become widespread in Australian society, and normalised in everyday settings, such as our mainstream media. Islamophobia cannot be treated with a singular approach or mode of intervention. Our study comes at a critical time; it provides empirical evidence on the extent of the problem, as well as documenting the varied manifestations of Islamophobic sentiment, with the view to developing potential action points and policy. In November 2019 we undertook a survey of 4019 Victorians. We asked questions on their attitudes towards cultural diversity, racial equality and privilege; trust and fairness; Muslims and Islam; and other ethno-cultural groups in Australian society; their experiences of racism and discrimination; their contact with Muslims and knowledge of Islam; and their political affiliation. To our knowledge, this was the largest survey undertaken in Victoria with the purpose of solely measuring Victorians perceptions of Muslims and Islam. Based on respondents’ answers, we used latent class analysis to segment the Victorian population. Five groups were generated: Islamophobic, Islamophobic with assimilationist tendencies, Undecided, Progressive with concerns about Islam, and Progressive. We then distilled the demographic and attitudinal attributes of these groups, with the view to identifying roles and drivers to help guide policy and intervention. We tested this five group segmentation with community organisations in Victoria working in the broad areas of diversity and multiculturalism, and with a particular emphasis on Muslim and non-Muslim relations. The groupings made sense on-the-ground, and they provided a strong pathway forward for program and policy design
International validation of Enhanced Recovery After Surgery Society guidelines on enhanced recovery for gynecologic surgery
Background: Enhanced Recovery After Surgery Society publishes guidelines on perioperative care, but these guidelines should be validated prospectively. Objective: To evaluate the association between compliance with Enhanced Recovery After Surgery Gynecologic/Oncology guideline elements and postoperative outcomes in an international cohort. Study Design: The study comprised 2101 patients undergoing elective gynecologic/oncology surgery between January 2011 and November 2017 in 10 hospitals across Canada, the United States, and Europe. Patient demographics, surgical/anesthesia details, and Enhanced Recovery After Surgery protocol compliance elements (pre-, intra-, and postoperative phases) were entered into the Enhanced Recovery After Surgery Interactive Audit System. Surgical complexity was stratified according to the Aletti scoring system (low vs medium/high). The following covariates were accounted for in the analysis: age, body mass index, smoking status, presence of diabetes, American Society of Anesthesiologists class, International Federation of Gynecology and Obstetrics stage, preoperative chemotherapy, radiotherapy, operating time, surgical approach (open vs minimally invasive), intraoperative blood loss, hospital, and Enhanced Recovery After Surgery implementation status. The primary end points were primary hospital length of stay and complications. Negative binomial regression was used to model length of stay, and logistic regression to model complications, as a function of compliance score and covariates. Results: Patient demographics included a median age 56 years, 35.5% obese, 15% smokers, and 26.7% American Society of Anesthesiologists Class III-IV. Final diagnosis was malignant in 49% of patients. Laparotomy was used in 75.9% of cases, and the remainder minimally invasive surgery. The majority of cases (86%) were of low complexity (Aletti score ≤3). In patients with ovarian cancer, 69.5% had a medium/high complexity surgery (Aletti score 4–11). Median length of stay was 2 days in the low- and 5 days in the medium/high-complexity group. Every unit increase in Enhanced Recovery After Surgery guideline score was associated with 8% (IRR, 0.92; 95% confidence interval, 0.90–0.95; P\u3c.001) decrease in days in hospital among low-complexity, and 12% (IRR, 0.88; 95% confidence interval, 0.82–0.93; P\u3c.001) decrease among patients with medium/high-complexity scores. For every unit increase in Enhanced Recovery After Surgery guideline score, the odds of total complications were estimated to be 12% lower (P\u3c.05) among low-complexity patients. Conclusion: Audit of surgical practices demonstrates that improved compliance with Enhanced Recovery After Surgery Gynecologic/Oncology guidelines is associated with an improvement in clinical outcomes, including length of stay, highlighting the importance of Enhanced Recovery After Surgery implementation
Racism in Australia : a protocol for a systematic review and meta-analysis
Background: Racism has been identified as a major source of injustice and a health burden in Australia and across the world. Despite the surge in Australian quantitative research on the topic, and the increasing recognition of the prevalence and impact of racism in Australian society, the collective evidence base has yet to be comprehensively reviewed or meta-analysed. This protocol describes the first systematic review and meta-analysis of racism in Australia at the national level, focussing on quantitative studies. The current study will considerably improve our understanding of racism, including its manifestations and fluctuation over time, variation across settings and between groups, and associations with health and socio-economic outcomes. Methods: The research will consist of a systematic literature review and meta-analysis. Searches for relevant studies will focus on the social and health science databases CINAHL, PsycINFO, PubMed and Scopus. Two reviewers will independently screen eligible papers for inclusion and extract data from included studies. Studies will be included in the review and meta-analysis where they meet the following criteria: (1) report quantitative empirical research on self-reported racism in Australia, (2) report data on the prevalence of racism, or its association with health (e.g. mental health, physical health, health behaviours) or socio-economic outcomes (e.g. education, employment, income), and (3) report Australian data. Measures of racism will focus on study participants’ self-reports, with a separate analysis dedicated to researcher-reported measures, such as segregation and differential outcomes across racial/ethnic groups. Measures of health and socio-economic outcomes will include both self-reports and researcher-reported measures, such as physiological measurements. Existing reviews will be manually searched for additional studies. Study characteristics will be summarised, and a meta-analysis of the prevalence of racism and its associations will be conducted using random effects models and mean weighted effect sizes. Moderation and subgroup analyses will be conducted as well. All analyses will use the software CMA 3.0. Discussion: This study will provide a novel and comprehensive synthesis of the quantitative evidence base on racism in Australia. It will answer questions about the fluctuation of racism over time, its variation across settings and groups, and its relationship with health and socio-economic outcomes. Findings will be discussed in relation to broader debates in this growing field of research and will be widely disseminated to inform anti-racism research, action and policy nationally. Systematic review registration: PROSPERO CRD42021265115
Identification of Mutant Genes and Introgressed Tiger Salamander DNA in the Laboratory Axolotl, \u3cem\u3eAmbystoma mexicanum\u3c/em\u3e
The molecular genetic toolkit of the Mexican axolotl, a classic model organism, has matured to the point where it is now possible to identify genes for mutant phenotypes. We used a positional cloning–candidate gene approach to identify molecular bases for two historic axolotl pigment phenotypes: white and albino. White (d/d) mutants have defects in pigment cell morphogenesis and differentiation, whereas albino (a/a) mutants lack melanin. We identified in white mutants a transcriptional defect in endothelin 3 (edn3), encoding a peptide factor that promotes pigment cell migration and differentiation in other vertebrates. Transgenic restoration of Edn3 expression rescued the homozygous white mutant phenotype. We mapped the albino locus to tyrosinase (tyr) and identified polymorphisms shared between the albino allele (tyra) and tyr alleles in a Minnesota population of tiger salamanders from which the albino trait was introgressed. tyra has a 142 bp deletion and similar engineered alleles recapitulated the albinophenotype. Finally, we show that historical introgression of tyrasignificantly altered genomic composition of the laboratory axolotl, yielding a distinct, hybrid strain of ambystomatid salamander. Our results demonstrate the feasibility of identifying genes for traits in the laboratory Mexican axolotl
Validation of miRNA signatures for ovarian cancer earlier detection in the pre-diagnosis setting using machine learning approaches
IntroductionEffective strategies for early detection of epithelial ovarian cancer are lacking. We evaluated whether a panel of 14 previously established circulating microRNAs could discriminate between cases diagnosed <2 years after serum collection and those diagnosed 2–7 years after serum collection. miRNA sequencing data from subsequent ovarian cancer cases were obtained as part of the ongoing multi-cancer JanusRNA project, utilizing pre-diagnostic serum samples from the Janus Serum Bank and linked to the Cancer Registry of Norway for cancer outcomes.MethodsWe included a total of 80 ovarian cancer cases contributing 80 serum samples and compared 40 serum samples from cases with samples collected <2 years prior to diagnosis with 40 serum samples from cases with sample collection ≥2 to 7 years. We employed the extreme gradient boosting (XGBoost) algorithm to train a binary classification model using 70% of the available data, while the model was tested on the remaining 30% of the dataset.ResultsThe performance of the model was evaluated using repeated holdout validation. The previously established set of miRNAs achieved a median area under the receiver operating characteristic curve (AUC) of 0.771 in the test sets. Four out of 14 miRNAs (hsa-miR-200a-3p, hsa-miR-1246, hsa-miR-203a-3p, hsa-miR-23b-3p) exhibited higher expression levels closer to diagnosis, consistent with the previously reported upregulation in cancer cases, with statistical significance observed only for hsa-miR-200a-3p (beta=0.14; p=0.04). DiscussionThe discrimination potential of the selected models provides evidence of the robustness of the miRNA signature for ovarian cancer
- …