Summer distribution of semi-domesticated reindeer relative to a new wind-power plant

Wind-power plants (WPs) within reindeer (Rangifer tarandus tarandus) habitat may have negative effects on reindeer habitat use. Avoidance effects towards a WP were tested by comparing reindeer distributions on a peninsula where a WP was built in 2006 with a control peninsula without a WP. Distributions were measured by direct observations during construction period, and in four subsequent years, and limited faecal pellet group counts along transects before, during and after the WP construction (2005–2010). We predicted higher reindeer density in the control than the WP peninsula and at increasing distances from the WP when controlling for habitat quality. We found no avoidance effects from the WP, with significantly more reindeer in the WP than the control peninsula. Faecal pellet group data supported a lack of negative effects towards the WP after construction compared to before, while area within 100 m from the access road to the WP was avoided during the construction period and for 3 years afterwards. Reindeer avoided low-quality habitat both in the control and WP peninsulas. Our study indicates that WP development might have minor effects on habitat use if built in poor habitats, at least for semi-domestic reindeer. Our results cannot be used to infer effects of a WP built in higher-quality habitats or where large-scale movements are less restrictive than on a peninsula. Disturbance effects of human infrastructure likely are context-dependent, and management should thus be careful in planning of WPs to minimize adverse effects.     

No Association of Cryptococcal Antigenemia with Poor Outcomes among Antiretroviral Therapy-Experienced HIV-Infected Patients in Addis Ababa,Ethiopia

Introduction

There are limited data on clinical outcomes of ART-experienced patients with cryptococcal antigenemia. We assessed clinical outcomes of a predominantly asymptomatic, ART-experienced cohort of HIV+ patients previously found to have a high (8.4%) prevalence of cryptococcal antigenemia.

Methods

The study took place at All Africa Leprosy, Tuberculosis and Rehabilitative Training Centre and Black Lion Hospital HIV Clinics in Addis Ababa, Ethiopia. A retrospective study design was used to perform 12-month follow-up of 367 mostly asymptomatic HIV-infected patients (CD4<200 cells/µl) with high levels of antiretroviral therapy use (74%) who were previously screened for cryptococcal antigenemia. Medical chart abstraction was performed approximately one year after initial screening to obtain data on clinic visit history, ART use, CD4 count, opportunistic infections, and patient outcome. We evaluated the association of cryptococcal antigenemia and a composite poor outcome of death and loss to follow-up using logistic regression.

Results

Overall, 323 (88%) patients were alive, 8 (2%) dead, and 36 (10%) lost to follow-up. Among the 31 patients with a positive cryptococcal antigen test (titers ≥1∶8) at baseline, 28 were alive (all titers ≤1∶512), 1 dead and 2 lost to follow-up (titers ≥1∶1024). In multivariate analysis, cryptococcal antigenemia was not predictive of a poor outcome (aOR = 1.3, 95% CI 0.3–4.8). A baseline CD4 count <100 cells/µl was associated with an increased risk of a poor outcome (aOR 3.0, 95% CI 1.4–6.7) while an increasing CD4 count (aOR 0.1, 95% CI 0.1–0.3) and receiving antiretroviral therapy at last follow-up visit (aOR 0.1, 95% CI 0.02–0.2) were associated with a reduced risk of a poor outcome.

Conclusions

Unlike prior ART-naïve cohorts, we found that among persons receiving ART and with CD4 counts <200 cells/µl, asymptomatic cryptococcal antigenemia was not predictive of a poor outcome.     

Quantifying the Contribution of Entire Free-Living Nematode Communities to Carbon Mineralization under Contrasting C and N Availability

To understand the roles of nematodes in organic matter (OM) decomposition, experimental setups should include the entire nematode community, the native soil microflora, and their food sources. Yet, published studies are often based on either simplified experimental setups, using only a few selected species of nematode and their respective prey, despite the multitude of species present in natural soil, or on indirect estimation of the mineralization process using O₂ consumption and the fresh weight of nematodes. We set up a six-month incubation experiment to quantify the contribution of the entire free living nematode community to carbon (C) mineralization under realistic conditions. The following treatments were compared with and without grass-clover amendment: defaunated soil reinoculated with the entire free living nematode communities (+Nem) and defaunated soil that was not reinoculated (-Nem). We also included untreated fresh soil as a control (CTR). Nematode abundances and diversity in +Nem was comparable to the CTR showing the success of the reinoculation. No significant differences in C mineralization were found between +Nem and -Nem treatments of the amended and unamended samples at the end of incubation. Other related parameters such as microbial biomass C and enzymatic activities did not show significant differences between +Nem and -Nem treatments in both amended and unamended samples. These findings show that the collective contribution of the entire nematode community to C mineralization is small. Previous reports in literature based on simplified experimental setups and indirect estimations are contrasting with the findings of the current study and further investigations are needed to elucidate the extent and the mechanisms of nematode involvement in C mineralization.     

QTL Mapping in New Arabidopsis thaliana Advanced Intercross-Recombinant Inbred Lines

Background

Even when phenotypic differences are large between natural or domesticated strains, the underlying genetic basis is often complex, and causal genomic regions need to be identified by quantitative trait locus (QTL) mapping. Unfortunately, QTL positions typically have large confidence intervals, which can, for example, lead to one QTL being masked by another, when two closely linked loci are detected as a single QTL. One strategy to increase the power of precisely localizing small effect QTL, is the use of an intercross approach before inbreeding to produce Advanced Intercross RILs (AI-RILs).

Methodology/Principal Findings

We present two new AI-RIL populations of Arabidopsis thaliana genotyped with an average intermarker distance of 600 kb. The advanced intercrossing design led to expansion of the genetic map in the two populations, which contain recombination events corresponding to 50 kb/cM in an F₂ population. We used the AI-RILs to map QTL for light response and flowering time, and to identify segregation distortion in one of the AI-RIL populations due to a negative epistatic interaction between two genomic regions.

Conclusions/Significance

The two new AI-RIL populations, EstC and KendC, derived from crosses of Columbia (Col) to Estland (Est-1) and Kendallville (Kend-L) provide an excellent resource for high precision QTL mapping. Moreover, because they have been genotyped with over 100 common markers, they are also excellent material for comparative QTL mapping.     

Determinants of exclusive breastfeeding practice to infants aged less than six months in Offa district,Southern Ethiopia: a cross-sectional study

Background

World Health Organization (WHO) recommends timely initiation of breastfeeding after birth and only feeding breast milk to infants during the first 6 months of life. It was estimated that exclusive breastfeeding can reduce infant deaths by 13%. The practice of exclusive breastfeeding is suboptimal in many parts of Ethiopia to a varied extent. Factors associated with exclusive breastfeeding practice and the proportion of its practice was not well documented in Offa district. Therefore, this study was aimed to assess the determinants of exclusive breastfeeding in the first 6 months of life in Offa district, Southern Ethiopia.

Methods

A community-based cross-sectional study was carried out in 396 mothers of infants younger than 6 months using random sampling. Data were collected from mothers of the infants by trained interviewers. Exclusive breastfeeding was measured by the history of infant feeding in the prior 24 h. Pretested and structured questionnaires adopted from standard questionnaires and Ethiopia linkages modules were used. Multivariate logistic regression was used to identify factors significantly influencing exclusive breastfeeding practice.

Results

Based on findings of this study of 396 participants, the proportion of exclusive breastfeeding was 78.0% and awareness of exclusive breastfeeding and bottle feeding were 85.6 and 6.1% respectively. About 6% of infants were given prelacteal feeds. The number of infants fed cow milk was 12.9%, formula 7.8%, water 8.5%, fruits and semisolids 1.5%, over 24 h prior to the survey. The initiation of breastfeeding within one h (AOR 2.2; 95% CI 1.1, 4.27), attending formal education (AOR 4; 95% CI 2.20, 7.25), having an awareness on the benefits of exclusive breastfeeding (AOR 6; 95% CI 3.10, 11.70) and knowledge of colostrum feeding (AOR 2.1; 95% CI 1.11, 4.27) had a statistically significant association with exclusive breastfeeding in the study area.

Conclusions

The practice of exclusive breastfeeding as well as awareness was worthy in Offa district. Additionally the proportion of bottle feeding use was small. However, feeding other than breast milk was associated with the perception that breast milk alone was insufficient for their child. Strategies on promoting exclusive breastfeeding practice must focus on strengthening women’s education and awareness creation activities further.

     

Affordable artificial intelligence-based digital pathology for neglected tropical diseases: A proof-of-concept for the detection of soil-transmitted helminths and Schistosoma mansoni eggs in Kato-Katz stool thick smears

BackgroundWith the World Health Organization’s (WHO) publication of the 2021–2030 neglected tropical diseases (NTDs) roadmap, the current gap in global diagnostics became painfully apparent. Improving existing diagnostic standards with state-of-the-art technology and artificial intelligence has the potential to close this gap.Methodology/Principal findingsWe prototyped an artificial intelligence-based digital pathology (AI-DP) device to explore automated scanning and detection of helminth eggs in stool prepared with the Kato-Katz (KK) technique, the current diagnostic standard for diagnosing soil-transmitted helminths (STHs; Ascaris lumbricoides, Trichuris trichiura and hookworms) and Schistosoma mansoni (SCH) infections. First, we embedded a prototype whole slide imaging scanner into field studies in Cambodia, Ethiopia, Kenya and Tanzania. With the scanner, over 300 KK stool thick smears were scanned, resulting in total of 7,780 field-of-view (FOV) images containing 16,990 annotated helminth eggs (Ascaris: 8,600; Trichuris: 4,083; hookworms: 3,623; SCH: 684). Around 90% of the annotated eggs were used to train a deep learning-based object detection model. From an unseen test set of 752 FOV images containing 1,671 manually verified STH and SCH eggs (the remaining 10% of annotated eggs), our trained object detection model extracted and classified helminth eggs from co-infected FOV images in KK stool thick smears, achieving a weighted average precision (± standard deviation) of 94.9% ± 0.8% and a weighted average recall of 96.1% ± 2.1% across all four helminth egg species.Conclusions/SignificanceWe present a proof-of-concept for an AI-DP device for automated scanning and detection of helminth eggs in KK stool thick smears. We identified obstacles that need to be addressed before the diagnostic performance can be evaluated against the target product profiles for both STH and SCH. Given that these obstacles are primarily associated with the required hardware and scanning methodology, opposed to the feasibility of AI-based results, we are hopeful that this research can support the 2030 NTDs road map and eventually other poverty-related diseases for which microscopy is the diagnostic standard.     

Correction to: Thanatological behavior of a female Leopard (Panthera pardus fusca)

acta ethologica - A correction to this paper has been published: https://doi.org/10.1007/s10211-021-00367-w     

Pyrethrin from Dalmatian pyrethrum (Tanacetum cinerariifolium (Trevir.) Sch. Bip.): biosynthesis,biological activity,methods of extraction and determination

Phytochemistry Reviews - Pyrethrin is a potent biopesticide, a natural mixture of six compounds (pyrethrin I and II, cinerin I and II, and jasmolin I and II), biosynthesized in plants of Dalmatian...     

Structural basis for cytokinin recognition by Arabidopsis thaliana histidine kinase 4

Cytokinins are classic hormones that orchestrate plant growth and development and the integrity of stem cell populations. Cytokinin receptors are eukaryotic sensor histidine kinases that are activated by both naturally occurring adenine-type cytokinins and urea-based synthetic compounds. Crystal structures of the Arabidopsis thaliana histidine kinase 4 sensor domain in complex with different cytokinin ligands now rationalize the hormone-binding specificity of the receptor and may spur the design of new cytokinin ligands.