The Importance of Dispersal for Bacterial Community Composition and Functioning

We conducted a metacommunity experiment to investigate the role of dispersal for bacterial community composition (BCC) and function of freshwater bacteria. Bacteria were dispersed from a common source pool into three different lake communities in their natural lake water. The experiment was conducted in dialysis bags to enable a decoupling between a change in the local environment and dispersal. BCC was determined by terminal restriction fragment length polymorphism (tRFLP) of the 16S rRNA gene. We show that the greatest changes in BCC occurred between 10% and 43% of dispersal of standing stock per day. Functioning, measured as growth rate, was also affected by dispersal in all three communities but the qualitative pattern differed between communities, sometimes showing a hump-shaped relationship to dispersal and sometimes decreasing with increasing dispersal. In all waters, functioning was related to BCC. Our results show that dispersal does affect BCC and functioning but that high dispersal rates are needed. Further, the effect of dispersal on BCC and function seem to depend on the quality of the habitat to which bacteria disperse into

Stent or Surgery for Malignant Low Bileduct Obstruction?

The development of non-surgical techniques for the relief of malignant low bileduct obstruction has cast doubt on the best way of relieving jaundice, particularly in patients fit for surgery whose life expectancy is more than a few weeks

Decomposing multiple dimensions of stability in global change experiments

Ecological stability is the central framework to understand an ecosystem’s ability to absorb or recover from environmental change. Recent modelling and conceptual work suggests that stability is a multidimensional construct comprising different response aspects. Using two freshwater mesocosm experiments as case studies, we show how the response to single perturbations can be decomposed in different stability aspects (resistance, resilience, recovery, temporal stability) for both ecosystem functions and community composition. We find that extended community recovery is tightly connected to a nearly complete recovery of the function (biomass production), whereas systems with incomplete recovery of the species composition ranged widely in their biomass compared to controls. Moreover, recovery was most complete when either resistance or resilience was high, the latter associated with low temporal stability around the recovery trend. In summary, no single aspect of stability was sufficient to reflect the overall stability of the system

Impact of Emergency Online Teaching on Teachers’ Professional Digital Competence: Experiences from the Nordic Higher Education Institutions

During the COVID-19 pandemic, Nordic higher education institutions (HEIs) as any other learning providers had to abruptly switch from onsite in-person delivery strategies to a more ‘pandemic-friendly’ online mode. To manage these emergent transformations of learning environments successfully, development of teachers’ digital competence became pivotal. This study investigates the experiences of teachers and students from HEIs in the Nordic countries of the impact of the transition to online teaching during the pandemic crisis on teachers’ professional digital competence (TPDC). The findings indicate that the pandemic promoted teachers’ creativity and innovation, enabling individual initiatives, openness, and decentralization that demonstrates the Nordic HEIs readiness to mobilize relevant digital infrastructure and exert academic freedom in times of crises. The study further broadens the concept of TPDC involving aspects of well-being and physical environment as additional indicators, to ensure equality, inclusion, and sustainability in the future of online education in higher education

Reconstructing Racially Polarized Voting

Racially polarized voting makes minorities more vulnerable to discriminatory changes in election laws and therefore implicates nearly every voting rights doctrine. In Thornburg v. Gingles , the Supreme Court held that racially polarized voting is a necessary—but not a sufficient—condition for a vote dilution claim under Section 2 of the Voting Rights Act. The Court, however, has recently questioned the propriety of recognizing the existence of racially polarized voting. This colorblind approach threatens not only the Gingles factors but also Section 2’s constitutionality. The Court treats racially polarized voting as a modern phenomenon. But the relevant starting point is the 1860s, not the 1960s. Prior to the Fifteenth Amendment’s passage, Republicans received overwhelming support from newly enfranchised Black voters in the former Confederate States and expected that support to continue. The Reconstruction Framers were thus attentive to the realities of racially polarized voting and openly recognized that extending the franchise would empower Black voters to mobilize politically and protect their own interests. Racially polarized voting was a feature—not a bug—in the passage and ratification of the Fifteenth Amendment. Accordingly, this Article argues that the Court’s treatment of racially polarized voting as a constitutional taboo is historically unfounded and doctrinally incoherent. There are significant implications for acknowledging the role of racially polarized voting during Reconstruction. This historical insight moves vote dilution claims—and their predicate finding of racially polarized voting—far closer to the heart of the Reconstruction Amendments and challenges the Court’s hostility to race-based redistricting. It is powerful evidence that Congress is well within its enforcement authority to remedy and deter dilutive measures that exploit racially polarized voting. Finally, reconstructing racially polarized voting helps reorient voting rights doctrine toward a Fifteenth Amendment framework

Clinical features and treatment response to differentiate idiopathic peritonitis from non-strangulating intestinal infarction of the pelvic flexure associated with Strongylus vulgaris infection in the horse

Background Peritonitis in horses secondary to non-strangulating infarction (NSII) has a guarded prognosis, even after intestinal resection. In contrast, horses with idiopathic peritonitis respond well to medical treatment. Affected horses in both cases often show signs of both colic and systemic inflammation, but early diagnosis is crucial for optimal treatment and an accurate prognosis. One cause of NSII is thrombus formation secondary to Strongylus vulgaris larval migration. There has been a documented increase in S. vulgaris prevalence in Sweden since the implementation of selective anthelmintic treatment in 2007, which subsequently could result in a rise in NSII cases. In a retrospective clinical study, medical records from cases diagnosed with NSII of the pelvic flexure or idiopathic peritonitis from three equine referral hospitals in Sweden during 2017-2020 were reviewed. Information including demographic data, relevant medical history, and clinical- and laboratory parameters were obtained from patient records. To facilitate the differentiation between cases of idiopathic peritonitis and cases with confirmed NSII of the pelvic flexure, the aim of the study was to compare clinical and laboratory parameters, clinical progression and initial response to antimicrobial treatment. A secondary aim was to compare survival-rates. Results Horses with NSII (n = 20) were significantly more likely to present during the winter months with a poorer response to medical treatment within 48 h. Cases of idiopathic peritonitis (n = 107) had a 100% survival rate with medical treatment, although one case required surgical correction of a colon displacement. In comparison, all confirmed NSII cases were non-responsive to antimicrobial treatment, with a survival rate to discharge of 50% after colon resection. Specific rectal findings and peripheral blood neutropenia were strongly associated with NSII. Conclusions In Sweden, idiopathic peritonitis cases still predominate over S. vulgaris associated NSII cases and have an excellent survival rate with antimicrobial treatment. However, horses presenting with septic peritonitis during the winter months with a palpable rectal mass and displaying fever and colic signs beyond 48 h of medical treatment are likely to suffer from NSII of the pelvic flexure and should be considered for abdominal surgery

Prenatal early food and multiple micronutrient supplementation trial reduced infant mortality in Bangladesh, but did not influence morbidity.

AIM: A previous maternal and infant nutrition intervention in rural Matlab, Bangladesh, showed that prenatal nutrient supplements improved child survival, but had no effect on size at birth. This secondary analysis examined whether prenatal multiple micronutrient supplements (MMS), on their own or combined with an early invitation to receive prenatal food supplements, affected child morbidity. METHODS: This randomised trial enrolled 4436 pregnant women from November 2001 to October 2003 and allocated them to early or standard invitations to food supplements, in the ninth and 20th weeks of pregnancy, respectively, and supplements of either the standard 60 mg iron with 400 μg folic acid, 30 mg iron with 400 μg folic acid or MMS. Quasi-Poisson regression was used to analyse morbidity. RESULTS: There were 3560 single live births and 3516 had morbidity data. The incidence rates of fever, diarrhoea and acute lower respiratory tract infection were 15.3, 3.6 and 2.3 episodes per person-year, respectively. The separate or combined interventions had no effect on morbidity up to 24 months. CONCLUSION: Early invitations to prenatal food supplements or prenatal MMS had no effect on common infections in rural Bangladesh, suggesting that earlier findings on improved child survival were not mediated by an effect on child morbidity

Effects of prenatal micronutrient and early food supplementation on metabolic status of the offspring at 4.5 years of age. The MINIMat randomized trial in rural Bangladesh.

BACKGROUND: Fetal nutritional insults may alter the later metabolic phenotype. We hypothesized that early timing of prenatal food supplementation and multiple micronutrient supplementation (MMS) would favourably influence childhood metabolic phenotype. METHODS: Pregnant women recruited 1 January to 31 December 2002 in Matlab, Bangladesh, were randomized into supplementation with capsules of either 30 mg of iron and 400 μg of folic acid, 60 mg of iron and 400 μg of folic acid, or MMS containing a daily allowance of 15 micronutrients, and randomized to food supplementation (608 kcal) either with early invitation (9 weeks' gestation) or usual invitation (at 20 weeks). Their children (n = 1667) were followed up at 4.5 years with assessment of biomarkers of lipid and glucose metabolism, inflammation and oxidative stress. RESULTS: Children in the group with early timing of food supplementation had lower cholesterol (difference -0.079 mmol/l, 95% confidence interval (CI) -0.156; -0.003), low-density lipoprotein (LDL) (difference -0.068 mmol/l, 95% CI -0.126; -0.011) and ApoB levels (difference -0.017 g/l, 95% CL -0.033; -0.001). MMS supplementation resulted in lower high-density lipoprotein (HDL) (difference -0.028 mmol/l, 95% CL -0.053; -0.002), lower glucose (difference -0.099 mmol/l, 95% CL -0.179; -0.019) and lower insulin-like growth factor 1 (IGF-1) (difference on log scale -0.141 µg/l, 95% CL -0.254; -0.028) than 60 mg iron and 400 μg folic acid. There were no effects on markers of inflammation or oxidative stress. CONCLUSIONS: Findings suggest that in a population where malnutrition is prevalent, nutrition interventions during pregnancy may modify the metabolic phenotype in the young child that could have consequences for later chronic disease risks

Genetic and Linguistic Coevolution in Northern Island Melanesia

Recent studies have detailed a remarkable degree of genetic and linguistic diversity in Northern Island Melanesia. Here we utilize that diversity to examine two models of genetic and linguistic coevolution. The first model predicts that genetic and linguistic correspondences formed following population splits and isolation at the time of early range expansions into the region. The second is analogous to the genetic model of isolation by distance, and it predicts that genetic and linguistic correspondences formed through continuing genetic and linguistic exchange between neighboring populations. We tested the predictions of the two models by comparing observed and simulated patterns of genetic variation, genetic and linguistic trees, and matrices of genetic, linguistic, and geographic distances. The data consist of 751 autosomal microsatellites and 108 structural linguistic features collected from 33 Northern Island Melanesian populations. The results of the tests indicate that linguistic and genetic exchange have erased any evidence of a splitting and isolation process that might have occurred early in the settlement history of the region. The correlation patterns are also inconsistent with the predictions of the isolation by distance coevolutionary process in the larger Northern Island Melanesian region, but there is strong evidence for the process in the rugged interior of the largest island in the region (New Britain). There we found some of the strongest recorded correlations between genetic, linguistic, and geographic distances. We also found that, throughout the region, linguistic features have generally been less likely to diffuse across population boundaries than genes. The results from our study, based on exceptionally fine-grained data, show that local genetic and linguistic exchange are likely to obscure evidence of the early history of a region, and that language barriers do not particularly hinder genetic exchange. In contrast, global patterns may emphasize more ancient demographic events, including population splits associated with the early colonization of major world regions