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Quantitative ethnobotanical knowledge is important in guiding sustainable resource use, yet for many medicinal plants such as Harpagophytum (Devil's claw), this information is scanty. Thus, we documented the ethnobotanical knowledge of Devil's claw in Hwange, Gwanda, Matobo, and Tsholotsho, western Zimbabwe, in relation to a person's age, gender, level of education, and locality. Using a semi-structured questionnaire, we interviewed 205 respondents on their knowledge of the physical features, distribution, uses and use-values, part used, and the method of preparation of Devil's claw. Physical identification was assessed based on the frequency of knowledge of plant parts. Binomial General Linear Models were used to test the effect of age, education, gender, and locality on the respondent's knowledge. Relationships of age, gender, level of education, and locality to ethnoecological perceptions were assessed using Pearson's Chi-square test. Use values were assessed based on Plant Part Value (PPV), Use Value category (UVk), and Overall Use Value (OUV). Ethnobotanical knowledge varied with locality and age, with better physical description in most adults and senior respondents in Hwange and Tsholotsho. Respondent's perceptions showed that Devil's claw was more abundant in Hwange and Tsholotsho relative to Matobo and Gwanda. Tubers (53%) were most valued in all localities followed by leaves (29%), and fruits (18%). Of the five identified categories of use, medicinal (UVk of 0.38) was the most important while ethnoveterinary, rituals, personal care, and food were least important (all UVks ≤0.02). OUVs were dependent on locality, significantly higher in Hwange and Tsholotsho (0.64 and 0.58, respectively) as compared to Gwanda (0.1) and Matobo (0.28). This study provides a wealth of knowledge that contributes to the preservation of indigenous knowledge of Devil's claw, sustainable management of the plant as well as further contribute to pharmacological interventions.

LiteBIRD Collaboration: et al., LiteBIRD is a future satellite mission designed to observe the polarization of the cosmic microwave background radiation in order to probe the inflationary universe. LiteBIRD is set to observe the sky using three telescopes with transition-edge sensor bolometers. In this work we estimated the LiteBIRD instrumental sensitivity using its current design. We estimated the detector noise due to the optical loadings using physical optics and ray-tracing simulations. The noise terms associated with thermal carrier and readout noise were modeled in the detector noise calculation. We calculated the observational sensitivities over fifteen bands designed for the LiteBIRD telescopes using assumed observation time efficiency., This work is supported in Japan by ISAS/JAXA for Pre-Phase A2 studies, by the acceleration program of JAXA research and development directorate, by the World Premier International Research Center Initiative (WPI) of MEXT, by the JSPS Core-to-Core Program of A. Advanced Research Networks, and by JSPS KAKENHI Grant Numbers JP15H05891, JP17H01115, and JP17H01125. The Italian LiteBIRD phase A contribution is supported by the Italian Space Agency (ASI Grants No. 2020-9-HH.0 and 2016-24-H.1-2018), the National Institute for Nuclear Physics (INFN), the National Institute for Astrophysics (INAF), and the Italian Ministry of Foreign Affairs and International Cooperation. The French LiteBIRD phase A contribution is supported by the Centre National d’Etudes Spatiale (CNES), by the Centre National de la Recherche Scientifique (CNRS), and by the Commissariat à l’Energie Atomique (CEA). The Canadian contribution is supported by the Canadian Space Agency. The US contribution is supported by NASA grant no. 80NSSC18K0132. Norwegian participation in LiteBIRD is supported by the Research Council of Norway (Grant No. 263011). The Spanish LiteBIRD phase A contribution is supported by the Spanish Agencia Estatal de Investigación (AEI), project refs. PID2019-110610RB-C21 and AYA2017-84185-P. Funds that support the Swedish contributions come from the Swedish National Space Agency (SNSA/Rymdstyrelsen) and the Swedish Research Council (Reg. no. 2019-03959). The German participation in LiteBIRD is supported in part by the Excellence Cluster ORIGINS, which is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy (Grant No. EXC-2094 - 390783311). This research used resources of the Central Computing System owned and operated by the Computing Research Center at KEK, as well as resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy.

Miombo woodlands near human settlements are under significant pressures from human activities, with negative consequences on their structure and composition. As studies are limited, we assessed the structure and species composition of a portion of miombo woodland along an increasing disturbance gradient from a national park, through a buffer zone to communal lands in northeast Zimbabwe. Five concentric plots of 2 and 11 m radii were established in each area to record woody species composition, diameter, height, basal area, density and volume as well as evidence of disturbance. Effects of site, growth stage and their interaction on vegetation diversity and structural parameters were tested using a general linear model (GLM). Principal component analysis (PCA) tested the association between species and site and ANOVA the differences in the level of disturbance across strata. Species diversity did not differ between sites except for evenness, which increased with disturbance. Evenness and richness were greater in seedlings and saplings than mature trees across sites, respectively. Sapling and mature tree diameters differed significantly between sites. Volume and density of mature trees declined with increasing disturbance while seedling densities peaked at intermediate disturbance levels (buffer zone). Tree harvesting, was more evident in the buffer zone and in the communal area relative to the national park. In contrast, fire frequency was greater in the national park and in the buffer zone relative to the communal area. The results of this study identify a true miombo woodland dominated by Brachystegia boehmii with a stable population, as illustrated by an inverse-J shape in diameter class distribution on all sites, and that these woodlands are generally resilient to disturbances, maintaining similar species composition and structure at various levels of disturbance. However, continued monitoring of disturbance levels and miombo woodland response is recommended to ensure sustainable utilisation of these resources.

Competition and facilitation vary inversely along environmental stress gradients. Here we ask how environmental stress along a slope gradient influences plant-plant interaction in a semi-arid savanna. We attempted to link spatial patterns and ecological interactions, so we analysed the spatial distribution of three Vachellia (Acacia) tree species and assessed the consequences of their interaction on plant structural variables (height, basal area, biomass and canopy cover) at Matopos Research Station, Zimbabwe. Spatial patterns among and between the tree species were assessed using both univariate and bivariate analysis. To understand the extent of tree species isolation, we applied the species mingling index. Canopy cover varied significantly between species at both ends of the stress gradient, while basal area did not differ among the three species at any slope position. The woodland showed differential recruitment levels for the three species across the catena, which may indicate future changes in composition. The mingling index showed that there was species isolation in the bottom and middle catena. Pair-wise interactions of plants reflected two common spatial patterns, clustering, interpreted as suggesting facilitation, and random, interpreted as neutral. In some cases these patterns changed with spatial scale, indicating that the stress gradient hypothesis (SGH) may be influenced by the spatial scale at which species are interacting. Our univariate analyses corroborate the evidence that plants in semi-arid environments have a clustered distribution and that catenas can produce differential recruitment levels of the different species.

For the past decade, the BICEP/Keck collaboration has been operating a series of telescopes at the Amundsen-Scott South Pole Station measuring degree-scale $B$-mode polarization imprinted in the Cosmic Microwave Background (CMB) by primordial gravitational waves (PGWs). These telescopes are compact refracting polarimeters mapping about 2% of the sky, observing at a broad range of frequencies to account for the polarized foreground from Galactic synchrotron and thermal dust emission. Our latest publication "BK18" utilizes the data collected up to the 2018 observing season, in conjunction with the publicly available WMAP and Planck data, to constrain the tensor-to-scalar ratio $r$. It particularly includes (1) the 3-year BICEP3 data which is the current deepest CMB polarization map at the foreground-minimum 95 GHz; and (2) the Keck 220 GHz map with a higher signal-to-noise ratio on the dust foreground than the Planck 353 GHz map. We fit the auto- and cross-spectra of these maps to a multicomponent likelihood model ($\Lambda$CDM+dust+synchrotron+noise+$r$) and find it to be an adequate description of the data at the current noise level. The likelihood analysis yields $\sigma(r)=0.009$. The inference of $r$ from our baseline model is tightened to $r_{0.05}=0.014^{+0.010}_{-0.011}$ and $r_{0.05}, Comment: 8 pages, 6 figures, contribution to the 2022 Cosmology session of the 56th Rencontres de Moriond

Constraining the Galactic foregrounds with multi-frequency Cosmic Microwave Background (CMB) observations is an essential step towards ultimately reaching the sensitivity to measure primordial gravitational waves (PGWs), the sign of inflation after the Big-Bang that would be imprinted on the CMB. The BICEP Array telescope is a set of multi-frequency cameras designed to constrain the energy scale of inflation through CMB B-mode searches while also controlling the polarized galactic foregrounds. The lowest frequency BICEP Array receiver (BA1) has been observing from the South Pole since 2020 and provides 30 GHz and 40 GHz data to characterize the Galactic synchrotron in our CMB maps. In this paper, we present the design of the BA1 detectors and the full optical characterization of the camera including the on-sky performance at the South Pole. The paper also introduces the design challenges during the first observing season including the effect of out-of-band photons on detectors performance. It also describes the tests done to diagnose that effect and the new upgrade to minimize these photons, as well as installing more dichroic detectors during the 2022 deployment season to improve the BA1 sensitivity. We finally report background noise measurements of the detectors with the goal of having photon noise dominated detectors in both optical channels. BA1 achieves an improvement in mapping speed compared to the previous deployment season., Comment: Proceedings of SPIE Astronomical Telescopes + Instrumentation 2022 (AS22)

We present the first linear polarization measurements from the 2015 long-duration balloon flight of SPIDER, an experiment designed to map the polarization of the cosmic microwave background (CMB) on degree angular scales. Results from these measurements include maps and angular power spectra from observations of 4.8% of the sky at 95 and 150 GHz, along with the results of internal consistency tests on these data. While the polarized CMB anisotropy from primordial density perturbations is the dominant signal in this region of sky, Galactic dust emission is also detected with high significance; Galactic synchrotron emission is found to be negligible in the SPIDER bands. We employ two independent foreground-removal techniques in order to explore the sensitivity of the cosmological result to the assumptions made by each. The primary method uses a dust template derived from Planck data to subtract the Galactic dust signal. A second approach, employing a joint analysis of SPIDER and Planck data in the harmonic domain, assumes a modified-blackbody model for the spectral energy distribution of the dust with no constraint on its spatial morphology. Using a likelihood that jointly samples the template amplitude and $r$ parameter space, we derive 95% upper limits on the primordial tensor-to-scalar ratio from Feldman-Cousins and Bayesian constructions, finding $r, 29 pages, 13 figures

We report on the design and performance of the BICEP3 instrument and its first three-year data set collected from 2016 to 2018. BICEP3 is a 52cm aperture, refracting telescope designed to observe the polarization of the cosmic microwave background (CMB) on degree angular scales at 95GHz. It started science observation at the South Pole in 2016 with 2400 antenna-coupled transition-edge sensor (TES) bolometers. The receiver first demonstrated new technologies such as large-diameter alumina optics, Zotefoam infrared filters, and flux-activated SQUIDs, allowing $\sim 10\times$ higher optical throughput compared to the Keck design. BICEP3 achieved instrument noise-equivalent temperatures of 9.2, 6.8 and 7.1$\mu\text{K}_{\text{CMB}}\sqrt{\text{s}}$ and reached Stokes $Q$ and $U$ map depths of 5.9, 4.4 and 4.4$\mu$K-arcmin in 2016, 2017 and 2018, respectively. The combined three-year data set achieved a polarization map depth of 2.8$\mu$K-arcmin over an effective area of 585 square degrees, which is the deepest CMB polarization map made to date at 95GHz., Comment: 35 pages, 35 figures, as submitted to ApJ, data and figures available for download at http://bicepkeck.org

We present results from an analysis of all data taken by the BICEP2, Keck Array and BICEP3 CMB polarization experiments up to and including the 2018 observing season. We add additional Keck Array observations at 220 GHz and BICEP3 observations at 95 GHz to the previous 95/150/220 GHz data set. The $Q/U$ maps now reach depths of 2.8, 2.8 and 8.8 $\mu{\mathrm K}_{cmb}$ arcmin at 95, 150 and 220 GHz respectively over an effective area of $\approx 600$ square degrees at 95 GHz and $\approx 400$ square degrees at 150 & 220 GHz. The 220 GHz maps now achieve a signal-to-noise on polarized dust emission exceeding that of Planck at 353 GHz. We take auto- and cross-spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz and evaluate the joint likelihood of the spectra versus a multicomponent model of lensed-$\Lambda$CDM+$r$+dust+synchrotron+noise. The foreground model has seven parameters, and no longer requires a prior on the frequency spectral index of the dust emission taken from measurements on other regions of the sky. This model is an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint $r_{0.05}, Comment: 22 pages, 24 figures, as published in PRL, data and figures available for download at http://bicepkeck.org

Despite the importance of termites in the structure and function of savanna ecosystems, long-term studies that examine the effects of several disturbance factors on termite communities are limited constraining our understanding of determinants of termite assemblages in savanna. We determined termite assemblages in six random plots (100 m × 2 m) each established on no fire, low fire, and moderate fire frequency sites in a communal area and a commercial cattle-wildlife ranch in a semi-arid savanna, southwest Zimbabwe. Environmental variables i.e., soil and plant variables were also determined in the termite sampling sites. Relationships of land use, fire, and their interaction to (i) termite assemblage and (ii) soil and plant variables were tested using a general linear model (GLM). Relationships between termite assemblages and soil and plant variables were explored using canonical correspondence analysis (CCA). Nineteen termite species from three sub-families were present, dominated by Macrotermitinae. Termite species richness and abundance were greater by a factor of up to 2.8 in the ranch than in the communal area. Termite abundance and species richness only differed with fire frequency in the ranch, being greater at low fire frequency than at moderate fire frequency or no fire. Although some relationships were observed between the environmental variables and the composition of termite assemblages, the lack of differences in environmental variables between land uses and fire frequencies suggested that other factors may better explain the patterns in termite assemblages in this savanna.

Background This study evaluated the in vitro antioxidant activity and comparison of anti-inflammatory and cytotoxic activity of Harpagopytum zeyheri with diclofenac. Methods In vitro assays were conducted using water, ethanol, and ethyl acetate extracts of H.zeyheri. The antioxidant activity was evaluated using the 2,2′-diphenyl-1-picrylhydrazy (DPPH) and 2,2′- azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays. The anti-inflammatory activity was determined by measuring the inhibition of nitric oxide (NO) on lipopolysaccharide (LPS)-induced RAW 264.7 mouse macrophages as well as cytokine (TNF-α and IL-10) expression on LPS-induced U937 human macrophages. For cytotoxicity, cell viability was determined using the 3-(4, 5-dimethylthiazol- 2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Results The ethyl acetate extract had the lowest IC50 values in the DPPH (5.91 μg/ml) and ABTS (20.5 μg/ml) assay compared to other extracts. Furthermore, the ethyl acetate extracts effectively inhibited NO and TNF-α and proved to be comparable to diclofenac at some concentrations. All extracts of H. zeyheri displayed dose-dependent activity and were associated with low levels of human-IL-10 expression compared to quercetin. Furthermore, all extracts displayed low toxicity relative to diclofenac. Conclusions These findings show that H. zeyheri has significant antioxidant activity. Additionally, similarities exist in the inflammatory activity of H. zeyheri to diclofenac at some concentrations as well as low toxicity in comparison to diclofenac.

We present a search for axion-like polarization oscillations in the cosmic microwave background (CMB) with observations from the Keck Array. A local axion field induces an all-sky, temporally sinusoidal rotation of CMB polarization. A CMB polarimeter can thus function as a direct-detection experiment for axion-like dark matter. We develop techniques to extract an oscillation signal. Many elements of the method are generic to CMB polarimetry experiments and can be adapted for other datasets. As a first demonstration, we process data from the 2012 observing season to set upper limits on the axion-photon coupling constant in the mass range $10^{-21}$-$10^{-18}~\mathrm{eV}$, which corresponds to oscillation periods on the order of hours to months. We find no statistically significant deviations from the background model. For periods larger than $24~\mathrm{hr}$ (mass $m < 4.8 \times 10^{-20}~\mathrm{eV}$), the median 95%-confidence upper limit is equivalent to a rotation amplitude of $0.68^\circ$, which constrains the axion-photon coupling constant to $g_{����} < \left ( 1.1 \times 10^{-11}~\mathrm{GeV}^{-1} \right ) m/\left (10^{-21}~\mathrm{eV} \right )$, if axion-like particles constitute all of the dark matter. The constraints can be improved substantially with data already collected by the BICEP series of experiments. Current and future CMB polarimetry experiments are expected to achieve sufficient sensitivity to rule out unexplored regions of the axion parameter space., 25 pages, 6 figures, 2 tables

The BICEP/Keck Collaboration is currently leading the quest to the highest sensitivity measurements of the polarized CMB anisotropies on degree scale with a series of cryogenic telescopes, of which BICEP Array is the latest Stage-3 upgrade with a total of $\sim32,000$ detectors. The instrument comprises 4 receivers spanning 30 to 270 GHz, with the low-frequency 30/40 GHz deployed to the South Pole Station in late 2019. The full complement of receivers is forecast to set the most stringent constraints on the tensor to scalar ratio $r$. Building on these advances, the overarching small-aperture telescope concept is already being used as the reference for further Stage-4 experiment design. In this paper I will present the development of the BICEP Array 150 GHz detector module and its fabrication requirements, with highlights on the high-density time division multiplexing (TDM) design of the cryogenic circuit boards. The low-impedance wiring required between the detectors and the first-stage SQUID amplifiers is crucial to maintain a stiff voltage bias on the detectors. A novel multi-layer FR4 Printed Circuit Board (PCB) with superconducting traces, capable of reading out up to 648 detectors, is presented along with its validation tests. I will also describe an ultra-high density TDM detector module we developed for a CMB-S4-like experiment that allows up to 1,920 detectors to be read out. TDM has been chosen as the detector readout technology for the Cosmic Microwave Background Stage-4 (CMB-S4) experiment based on its proven low-noise performance, predictable costs and overall maturity of the architecture. The heritage for TDM is rooted in mm- and submm-wave experiments dating back 20 years and has since evolved to support a multiplexing factor of 64x in Stage-3 experiments., Comment: 9 pages, 5 figure, Proceeding of LTD19 submitted to Journal of Low Temperature Physics

We present an improved search for axion-like polarization oscillations in the cosmic microwave background (CMB) with observations from the Keck Array. An all-sky, temporally sinusoidal rotation of CMB polarization, equivalent to a time-variable cosmic birefringence, is an observable manifestation of a local axion field and potentially allows a CMB polarimeter to detect axion-like dark matter directly. We describe improvements to the method presented in previous work, and we demonstrate the updated method with an expanded dataset consisting of the 2012-2015 observing seasons. We set limits on the axion-photon coupling constant for mass $m$ in the range $10^{-23}$-$10^{-18}~\mathrm{eV}$, which corresponds to oscillation periods on the order of hours to years. Our results are consistent with the background model. For periods between $1$ and $30~\mathrm{d}$ ($1.6 \times 10^{-21} \leq m \leq 4.8 \times 10^{-20}~\mathrm{eV}$), the $95\%$-confidence upper limits on rotation amplitude are approximately constant with a median of $0.27^\circ$, which constrains the axion-photon coupling constant to $g_{\phi\gamma} < (4.5 \times 10^{-12}~\mathrm{GeV}^{-1}) m/(10^{-21}~\mathrm{eV}$), if axion-like particles constitute all of the dark matter. More than half of the collected BICEP dataset has yet to be analyzed, and several current and future CMB polarimetry experiments can apply the methods presented here to achieve comparable or superior constraints. In the coming years, oscillation measurements can achieve the sensitivity to rule out unexplored regions of the axion parameter space., Comment: 14 pages, 3 figures

We present constraints on extensions to the $��$CDM cosmological model from measurements of the $E$-mode polarization auto-power spectrum and the temperature-$E$-mode cross-power spectrum of the cosmic microwave background (CMB) made using 2018 SPT-3G data. The extensions considered vary the primordial helium abundance, the effective number of relativistic degrees of freedom, the sum of neutrino masses, the relativistic energy density and mass of a sterile neutrino, and the mean spatial curvature. We do not find clear evidence for any of these extensions, from either the SPT-3G 2018 dataset alone or in combination with baryon acoustic oscillation and \textit{Planck} data. None of these model extensions significantly relax the tension between Hubble-constant, $H_0$, constraints from the CMB and from distance-ladder measurements using Cepheids and supernovae. The addition of the SPT-3G 2018 data to \textit{Planck} reduces the square-root of the determinants of the parameter covariance matrices by factors of $1.3 - 2.0$ across these models, signaling a substantial reduction in the allowed parameter volume. We also explore CMB-based constraints on $H_0$ from combined SPT, \textit{Planck}, and ACT DR4 datasets. While individual experiments see some indications of different $H_0$ values between the $TT$, $TE$, and $EE$ spectra, the combined $H_0$ constraints are consistent between the three spectra. For the full combined datasets, we report $H_0 = 67.49 \pm 0.53\,\mathrm{km\,s^{-1}\,Mpc^{-1}}$, which is the tightest constraint on $H_0$ from CMB power spectra to date and in $4.1\,��$ tension with the most precise distance-ladder-based measurement of $H_0$. The SPT-3G survey is planned to continue through at least 2023, with existing maps of combined 2019 and 2020 data already having $\sim3.5\times$ lower noise than the maps used in this analysis., Submitted to PRD; 19 pages, 7 figures

In this work, a liquid-liquid microextraction methodology using solidified floating organic drop (SFODME) was combined with liquid chromatography and UV/Vis detection to determine non-steroidal anti-inflammatory drugs (NSAIDs) naproxen (NPX), diclofenac (DCF), and mefenamic acid (MFN) in tap water, surface water, and seawater samples. Parameters that can influence the efficiency of the process were evaluated, such as the type and volume of the extractor and dispersive solvents, effect of pH, agitation type, and ionic strength. The optimized method showed low detection limits (0.09 to 0.25 μg L-1), satisfactory recovery rates (90 to 116%), and enrichment factors in the range between 149 and 199. SFODME showed simplicity, low cost, speed, and high concentration capacity of the analytes under study. Its use in real samples did not demonstrate a matrix effect that would compromise the effectiveness of the method, being possible to apply it successfully in water samples with different characteristics. published

Recent developments of transition-edge sensors (TESs), based on extensive experience in ground-based experiments, have been making the sensor techniques mature enough for their application on future satellite cosmic microwave background (CMB) polarization experiments. LiteBIRD is in the most advanced phase among such future satellites, targeting its launch in Japanese Fiscal Year 2027 (2027FY) with JAXA’s H3 rocket. It will accommodate more than 4000 TESs in focal planes of reflective low-frequency and refractive medium-and-high-frequency telescopes in order to detect a signature imprinted on the CMB by the primordial gravitational waves predicted in cosmic inflation. The total wide frequency coverage between 34 and 448GHz enables us to extract such weak spiral polarization patterns through the precise subtraction of our Galaxy’s foreground emission by using spectral differences among CMB and foreground signals. Telescopes are cooled down to 5K for suppressing thermal noise and contain polarization modulators with transmissive half-wave plates at individual apertures for separating sky polarization signals from artificial polarization and for mitigating from instrumental 1/f noise. Passive cooling by using V-grooves supports active cooling with mechanical coolers as well as adiabatic demagnetization refrigerators. Sky observations from the second Sun–Earth Lagrangian point, L2, are planned for 3years. An international collaboration between Japan, the USA, Canada, and Europe is sharing various roles. In May 2019, the Institute of Space and Astronautical Science, JAXA, selected LiteBIRD as the strategic large mission No. 2.

We perform the first simultaneous Bayesian parameter inference and optimal reconstruction of the gravitational lensing of the cosmic microwave background (CMB), using 100 deg$^2$ of polarization observations from the SPTpol receiver on the South Pole Telescope. These data reach noise levels as low as 5.8 $\mu$K-arcmin in polarization, which are low enough that the typically used quadratic estimator (QE) technique for analyzing CMB lensing is significantly sub-optimal. Conversely, the Bayesian procedure extracts all lensing information from the data and is optimal at any noise level. We infer the amplitude of the gravitational lensing potential to be $A_\phi\,{=}\,0.949\,{\pm}\,0.122$ using the Bayesian pipeline, consistent with our QE pipeline result, but with 17\% smaller error bars. The Bayesian analysis also provides a simple way to account for systematic uncertainties, performing a similar job as frequentist "bias hardening," and reducing the systematic uncertainty on $A_\phi$ due to polarization calibration from almost half of the statistical error to effectively zero. Finally, we jointly constrain $A_\phi$ along with $A_{\rm L}$, the amplitude of lensing-like effects on the CMB power spectra, demonstrating that the Bayesian method can be used to easily infer parameters both from an optimal lensing reconstruction and from the delensed CMB, while exactly accounting for the correlation between the two. These results demonstrate the feasibility of the Bayesian approach on real data, and pave the way for future analysis of deep CMB polarization measurements with SPT-3G, Simons Observatory, and CMB-S4, where improvements relative to the QE can reach 1.5 times tighter constraints on $A_\phi$ and 7 times lower effective lensing reconstruction noise., Comment: 27 pages, 14 figures, accompanying software package available at https://cosmicmar.com/CMBLensing.jl

We present a catalog of 4195 optically confirmed Sunyaev-Zel'dovich (SZ) selected galaxy clusters detected with signal-to-noise > 4 in 13,211 deg$^2$ of sky surveyed by the Atacama Cosmology Telescope (ACT). Cluster candidates were selected by applying a multi-frequency matched filter to 98 and 150 GHz maps constructed from ACT observations obtained from 2008-2018, and confirmed using deep, wide-area optical surveys. The clusters span the redshift range 0.04 < z < 1.91 (median z = 0.52). The catalog contains 222 z > 1 clusters, and a total of 868 systems are new discoveries. Assuming an SZ-signal vs. mass scaling relation calibrated from X-ray observations, the sample has a 90% completeness mass limit of M500c > 3.8 x 10$^{14}$ MSun, evaluated at z = 0.5, for clusters detected at signal-to-noise ratio > 5 in maps filtered at an angular scale of 2.4'. The survey has a large overlap with deep optical weak-lensing surveys that are being used to calibrate the SZ-signal mass-scaling relation, such as the Dark Energy Survey (4566 deg$^2$), the Hyper Suprime-Cam Subaru Strategic Program (469 deg$^2$), and the Kilo Degree Survey (825 deg$^2$). We highlight some noteworthy objects in the sample, including potentially projected systems; clusters with strong lensing features; clusters with active central galaxies or star formation; and systems of multiple clusters that may be physically associated. The cluster catalog will be a useful resource for future cosmological analyses, and studying the evolution of the intracluster medium and galaxies in massive clusters over the past 10 Gyr., 35 pages, 27 figures, accepted for publication in ApJS; v1.0 catalogs will be available from LAMBDA https://lambda.gsfc.nasa.gov/product/act/actpol_prod_table.cfm; v1.0 catalogs available from https://astro.ukzn.ac.za/~mjh/ACTDR5/v1.0/ until then

Although the ecosystem engineering role of termites has long been recognized, understanding the distribution and properties of their nests that affect ecosystem heterogeneity continues to be a priority. Studies have investigated soil properties like clay and organic matter (OM) composition of mounds belonging to fungus growing termites, however, little is known for southern African savanna soil feeding termites. Indeed, studies on the spatial distribution of termite mounds in savannas have been carried out with a focus mainly on the genus Macrotermes in savanna woodlands, leaving us with little information on other species that often occur on grasslands, for example soil feeding Cubitermes. Therefore, in this study we aimed to understand the effect of rainfall on Cubitermes breviceps mounds structure, soil properties and spatial point patterning at three sites. At each site two 25 m × 25 m plots were marked for spatial analysis. Mound height and basal diameter were recorded. Two soil properties (clay and OM) from mound and savanna matrix soil were investigated. A decreasing trend in mound height and diameter was observed from the more arid to the wettest site. Mound height was positively influenced by the amount of both clay and OM. However, both clay and OM had a negative relationship with numerical density of mounds, and we suggest other factors such as grass cover and the prevailing conditions such as moisture and competition at early colony establishment also influence mound density. Cubitermes breviceps mounds were generally completely spatially random across sites, except for Ripley’s L summary function that showed clustering, which we attribute to its cumulative nature. In conclusion, soil feeding C. breviceps incorporate more OM in their mounds and do not show competition between colonies probably due to them not feeding on limited food resources in the savanna such as grass and wood.

Termite mounds by creating patches of increased resource availability (e.g. water and nutrients) are a major source of spatial heterogeneity in savannas. Likewise, mistletoes via input of nutrient-rich litter alter nutrient and water availability increasing environmental heterogeneity in semi-arid savanna. Despite this recognition, the influence of termitaria and mistletoe on soil properties and plant community have not been investigated together. We established eight 100 m2 plots each on termitaria, under mistletoe-infected trees and in the surrounding savanna and examined the soil properties and the structure of Securinega virosa (Euphorbiaceae) and Euclea divinorum (Ebenaceae) in semi-arid savanna, southwest Zimbabwe. Soil properties significantly differed among the sampling sites (p = 0.001) with soils of increasing clay, soil moisture, pH and phosphorus, calcium and ammonium concentrations occurring on termite mounds. Soils under mistletoe-infected trees were associated with silt, organic matter, sodium, potassium, magnesium and nitrate and the surrounding savanna was associated with soils of increasing sand content. Plant structure also differed significantly between sites with greater basal area of both S. virosa and E. divinorum on termitaria relative to mistletoe-infected trees and the surrounding savanna. However, the stem density of S. virosa was greater under mistletoe-infected trees than on termitaria and in the surrounding savanna. Plant structural variables of individuals of the same species were affected by different soil properties across treatments. The major patterns showed that plant structure was influenced positively by soil moisture and nitrate and negatively by phosphorus on termitaria; positively by clay, soil moisture and ammonium and negatively by potassium under mistletoe-infected trees; and by phosphorus and calcium in the surrounding savanna. These findings show that soil properties, plant structure and their relationships differ between termitaria, mistletoe-infected trees and surrounding savanna, and these differences are suggested to increase heterogeneity in soil resources availability and vegetation structure in semi-arid savanna.

In savanna ecosystems, tree canopy patches differ in plant species composition compared to adjacent intercanopy spaces due to different levels of resource availabilities. Mistletoes further augment nutrients underneath tree canopies whilst reducing their hosts’ competitive edge, thus providing more resources and creating patches that support higher understory species richness. However, little is known on how understory species and functional trait assemblages, in both canopy and intercanopy spaces, are affected by varying overstory mistletoe infection intensities. This study investigated how functional and species diversity/composition varied within and between canopy patches and intercanopy spaces of high- and low mistletoe-infected Vachellia karroo trees. The affinity of individual species to the different canopy patches and intercanopy spaces was also assessed. Microhabitats had significantly different species compositions. A higher proportion of species (34%) showed a strong positive affinity towards canopy patches whilst intercanopy spaces were strongly associated with only 9% of recorded species, indicating greater dominance of some species there. Generally, subcanopy patches had significantly higher species richness and diversity, and functional diversity, compared to adjacent intercanopy spaces. These variables increased with increasing mistletoe infection, thus grass, forb and tree species diversity were 17–43% higher, and functional diversity indices were 0.5–28% greater in high- compared to low mistletoe-infection canopy patches. Furthermore, species richness and diversity of C3, C4, annual and perennial plants were 1.27–3.13-fold higher within canopy patches compared to intercanopy spaces and 1.28–1.74-fold greater within high- compared to low mistletoe-infection microhabitats. Consequently, high mistletoe-infection canopy patches had between 1.08 and 3.76-fold greater species richness and diversity of C3, C4, annual and perennial plants compared to the other three microhabitats. Our findings suggest that by enhancing spatial heterogeneity, variations in mistletoe infection facilitate biodiversity and to a lesser extent vegetation structural diversity in these semi-arid savannas.

Harvesting of large, hard timber trees for tobacco curing and barn construction affects the integrity of miombo woodlands, yet impacts have been quantified in a few studies despite the recent increase in tobacco farming in rural Zimbabwe. Therefore, we examined nature of disturbances, vegetation structure, and woody assemblage of miombo woodland in five plots (20 m × 20 m) each established within 1 km, 2.5 km, and 4 km from the boundary of a smallholder tobacco production communal land in northeast Zimbabwe. Fire, livestock grazing, firewood and pole collection, and land clearing were the major anthropogenic disturbances, being more prevalent closer to the communal area. Consequently, these disturbances declined with increasing distance from the communal area. Although the majority of the species were associated with the more disturbed sites in the communal area, species diversity did not differ between the sampling categories. Tree height, diameter, and basal area increased but sapling density declined with distance from the communal area. Seedlings were larger and denser within the communal area boundary while mature trees were denser, dominant, and species-rich further away from the communal area. In all sampling categories, the diameter size-class distribution followed an inverse J-shape dominated by young trees indicating a stable, regenerating population. Together, our results show that, in response to disturbance, miombo woodland structure changes into a shrub-rich plant community, but species composition is unaffected due to resprouting and coppicing from stumps remaining on the site. Although the inverse J-shape observed in all sampled sites indicate a potentially resilient and persistent population, monitoring over longer periods is recommended to ensure sustainable use and better inform policy on woodland management in agriculture-dominated areas.

Despite the increasing recognition of the ecological role of mistletoes, little is known about their genetic diversity. In this regard, we assessed the genetic variation within and among populations of Viscum verrucosum using random amplified polymorphic DNA (RAPDs). Analysis of molecular variance (AMOVA) and phylogenetic analysis based on genetic distance matrices were used to partition variation within and among populations, and the relationship between geographical and genetic distance was established using a Mantel's test. Mean population genetic diversity was high (P = 77.19%, A = 1.58, h = 0.30, Hʹ = 0.44) relative to other outcrossing mistletoe species. Genetic differentiation among the populations was high (GST = 0.366), also with low gene flow (Nm = 0.433) among populations. The genetic distance was significantly correlated to geographic distance (r = −0.849, p = 0.002), consistent with isolation-by-distance model suggesting constrained genetic exchange between geographically distant populations. Consequently, most of the genetic variation was retained within (63%) than among (37%) populations. In conclusion, findings of this study suggest that isolation-by-distance coupled with low seed dispersal limit gene flow, and determine the high levels of genetic structure of V. verrucosum populations, while historically elevated rates of gene flow may explain the high genetic diversity detected in these populations.

Bush encroachment has serious consequences on ecosystem functioning through alteration of species composition and ecosystem productivity. However, little is known regarding the spatial patterning of invading shrubs in semi-arid savannas. Cartesian coordinates of two invading woody species (Vachellia karrooandV. nilotica), were recorded in a 20 × 20-m plot on a grassland at Matopos research station, south-west Zimbabwe. We recorded a total of 308 plants including both saplings and shrubs from the two study plant species. Second-order spatial statistics was applied in order to understand the spatial pattern of encroaching plants. We predicted that the encroaching plants would be spatially aggregated because of facilitation that occurs in harsh environmental conditions. Consistent with our predictions, the two species were aggregated, with no evidence of inter- and intra specific species competition. This study demonstrates that encroaching trees in semi-arid savanna generally do not show self organization during early growth stages.

Disturbance, particularly agricultural expansion is one of the major threats to the biodiversity and ecological functions of tropical and sub-tropical ecosystems. In this regard, we examined changes in the species richness, abundance, and diversity of termites across different disturbance treatments in a sub-tropical semi-arid savanna in south eastern Zimbabwe. Nine transects (100 × 2 m) representing three habitat disturbance treatments (primary woodland; grazing area; agricultural field) were sampled for termites using a rapid biodiversity assessment protocol. Termites were more abundant and species-rich in primary woodland and grazing area than in the agricultural field. Twelve termite species from three sub-families were present, with Microtermes sp. constituting 35% of the identified termite species. Termite feeding group structure differed significantly among land-use types, and of all termites present, wood-feeding termites were the most abundant while soil-feeders were rare in the agricultural field. In conclusion the observed pattern in termite species richness and relative abundance indicates that termites are very resilient to natural disturbance and might actually benefit from some natural disturbances like they did in the grazing area of this study, but they are not resilient to extreme anthropogenic disturbance. Although there was no notable difference in termite species richness and relative abundance between agricultural field and primary woodland, the pattern observed across the three sites may be potential support for the IDH suggesting that intermediate levels of physical disturbance intensity influence the structure and functioning of termite assemblages in semi-arid savanna.

Hydrogel amendments have been used to improve seedling survival and establishment particularly in dry environments. However, their effect on survival and growth of newly transplanted seedlings under varying water stress conditions is poorly known. In this regard, we examined the effects of Aqua Matrix Forestry®, a potassium-based water-absorbent polymer, on the survival and early growth of Pinus patula seedlings planted in early-, mid- and late-dry season in the eastern highlands of Zimbabwe. The late-dry season was hotter and received more rainfall than the early- and mid-dry season. Hydrogel increased seedling survival by 34 and 22% in the mid- and late-dry season, respectively. Also, hydrogel-treated seedlings were significantly taller than untreated seedlings (P

Little is known on the influence of invasive aquatic weeds on afro-tropical waterbird communities. We used bird counts in sites of varying floating pennywort Hydrocotyle ranunculoides cover to explore the relationship between the weed and the waterbird community dynamics at Ngamo dam, Antelope Park, Zimbabwe. Waterbird communities in low-to-medium weed cover sites were more diverse and abundant compared to sites of high weed cover. In addition to supporting birds such as African Jacana which are able to forage within dense aquatic plants, high weed cover sites were associated with birds whose diets include invertebrates and fish which are likely more abundant and diverse in these sites. In contrast, low-to-medium weed cover sites were associated with bird species such as Common Moorhen, Great Egret, Pied Kingfisher and African Fish Eagle which require accessible open water and forage for diving, swimming or wading. The increased bird abundance in low-to-medium weed cover sites also likely increases prey for predatory birds. Thus, the negative changes in the waterbird community composition, abundance and diversity in response to increasing floating pennywort cover reflects species-specific tolerances to floating pennywort and its influence on accessible open water, foraging sites and prey availability.

The water quality and phytoplankton community assemblage of the Khami River, a tropical river sub catchment in semi-arid southwest Zimbabwe impacted by agriculture and urban land use, were examined in March 2015. Conductivity, sulphates, total dissolved solids and salinity were higher at urban sampling points than at agricultural sampling points. In contrast, agricultural sampling points were more turbid, and had a greater content of nitrates than urban sampling points. The phytoplankton community was dominated by Cyanobacteria, mainly Microcystis aeruginosa, with densities of up to 20 times higher at urban than at agricultural sampling points. There was an increasing dominance of Cyanobacteria (M. aerugionosa and Merismopedia glauca) and Chlorophyta (Eudorina elegans, Spirogyra sp. and Pediastrum duplex) and a decreasing importance of Bacillariophyta along the agriculture-to-urban gradient. Given the increasing scarcity of water in southern Africa, not only do our findings confirm the importance of land ...

We study the polarisation properties of extragalactic sources at 95 and 150 GHz in the SPTpol 500 deg$^2$ survey. We estimate the polarised power by stacking maps at known source positions, and correct for noise bias by subtracting the mean polarised power at random positions in the maps. We show that the method is unbiased using a set of simulated maps with similar noise properties to the real SPTpol maps. We find a flux-weighted mean-squared polarisation fraction $\langle p^2 \rangle= [8.9\pm1.1] \times 10^{-4}$ at 95 GHz and $[6.9\pm1.1] \times 10^{-4}$ at 150~GHz for the full sample. This is consistent with the values obtained for a sub-sample of active galactic nuclei. For dusty sources, we find 95 per cent upper limits of $\langle p^2 \rangle_{\rm 95}, 10 pages, 5 figures

The high-frequency telescope for LiteBIRD is designed with refractive and reflective optics. In order to improve sensitivity, this paper suggests the new optical configurations of the HFT which have approximately 7 times larger focal planes than that of the original design. The sensitivities of both the designs are compared, and the requirement of anti-reflection (AR) coating on the lens for the refractive option is derived. We also present the simulation result of a sub-wavelength AR structure on both surfaces of silicon, which shows a band-averaged reflection of 1.1–3.2% at 101–448 GHz.

Termites through mound construction and foraging activities contribute significantly to carbon and nutrient fluxes in nutrient-poor savannas. Despite this recognition, studies on the influence of termite mounds on carbon and nitrogen dynamics in sub-tropical savannas are limited. In this regard, we examined soil nutrient concentrations, organic carbon and nitrogen mineralization in incubation experiments in mounds of Macrotermes falciger and surrounding soils of sub-tropical savanna, northeast Zimbabwe. We also addressed whether termite mounds altered the plant community and if effects were similar across functional groups i.e. grasses, forbs or woody plants. Mound soils had significantly higher silt and clay content, pH and concentrations of calcium (Ca), magnesium (Mg), potassium (K), organic carbon (C), ammonium (NH4+) and nitrate (NO3−) than surrounding soils, with marginal differences in phosphorus (P) and sodium (Na) between mounds and matrix soils. Nutrient enrichment increased by a factor ranging from 1.5 for C, 4.9 for Mg up to 10.3 for Ca. Although C mineralization, nitrification and nitrification fraction were similar between mounds and matrix soils, nitrogen mineralization was elevated on mounds relative to surrounding matrix soils. As a result, termite mounds supported unique plant communities rich and abundant in woody species but less diverse in grasses and forbs than the surrounding savanna matrix in response to mound-induced shifts in soil parameters specifically increased clay content, drainage and water availability, nutrient status and base cation (mainly Ca, Mg and Na) concentration. In conclusion, by altering soil properties such as texture, moisture content and nutrient status, termite mounds can alter the structure and composition of sub-tropical savanna plant communities, and these results are consistent with findings in other savanna systems suggesting that increase in soil clay content, nutrient status and associated changes in the plant community assemblage may be a general property of mound building termites.

Spatial patterns are important to understanding factors that shape many ecological processes in natural plant and animal communities. However, the spatial patterns of Cubitermes mounds remain poorly understood despite their importance in many ecological processes in savanna ecosystems. We assessed the structural characteristics and spatial patterns of Cubitermes mounds in 25 × 25 m plots along a catena sequence i.e. upper, middle and bottom in a seasonal savanna wetland. A density of 1317 mounds ha− 1 was estimated for this savanna system. Mound density decreased whereas mound size increased down the catena, and mounds were absent in the floor region of the catena due to prolonged inundation. Spatial analysis showed that mounds were randomly distributed in the upper section of the catena and either random or clustered in the middle and bottom sections. True segregation between large and small mounds only occurred in the upper section of the catena; otherwise small mounds were either randomly distributed or clustered in relation to large mounds in the middle and bottom sections of the catena. With increase in spatial scale, however, mounds were independent indicating the absence of interaction between mounds. In the bottom region of the catena, mounds were independent at small spatial scales but positively correlated with increase in spatial scales a result consistent with low mound density and mutual stimulation, respectively. In conclusion, along the catena sequence, mound size and spatial distribution are a function of competition in the upper regions, whereas in the bottom regions these characteristics appear to be regulated by inundation. The study highlights the importance of hydrology, topography and competition for the structure and spatial patterning of Cubitermes mounds, and consequently for the spatial heterogeneity of ecological processes in savanna ecosystems.

Parasitic plants via input of nutrient-rich litter increase nutrient supply and enhance growth of other plants. Despite this recognition, the effects of parasitic plant litter on community structure remain poorly understood. We investigated the effects of mistletoe on leaf litter, soil fertility and the understorey grass species composition and biomass yield in semi-arid savanna, southwest Zimbabwe. Leaf litter was significantly greater by up to 39 % beneath infected trees than beneath uninfected trees due to the additional mistletoe litter and the effect of mistletoe on infected tree leaf litter. As a result, soil nutrient concentrations under infected trees were higher by 34 % for N, 36 % for Mg, 46 % for P up to 72 % for K than those below uninfected trees. Associated with these changes in leaf litter and soil nutrient concentrations was an increase in the species richness, density and biomass yield of the understorey grass community. Changes in leaf litter and soil fertility also led to altered root biomass allocation in Andropogon gayanus. Therefore, by increasing leaf litter and soil fertility under canopies of infected trees, mistletoe positively influences the composition, productivity and biomass allocation of understorey grasses. These findings reflect similar findings with other parasitic plants suggesting that increase in litterfall, soil fertility and plant species composition and productivity may be a general consequence of parasitic plants.

Mistletoes are preferred nesting sites for many bird species in a range of habitats. However, no studies have examined the use of mistletoes by nesting birds in the semi-arid savannah. We studied nesting in mistletoe and its role in determining nesting success in the Grey Go-away-bird in south-west Zimbabwe. We modelled the effects of mistletoe, mistletoe abundance, nest microclimate, concealment and nest height on daily survival rates (DSR) using program MARK. A constant survival model was best fitted for the Grey Go-away-bird suggesting a constant nest survival rate across the nesting period. Mistletoe nests had lower DSR than nests placed elsewhere in the canopy. Mistletoe abundance and nest height had a positive association with DSR whereas visibility distance, microclimate and concealment were negatively associated with DSR. Overall, survival for nests in mistletoe was 22.1% compared with 90.5% for nests in other substrates over the 50-day nesting period. In conclusion, the low nest survival in mistletoe suggests either that the factors used to select mistletoe as nest sites by these birds are poor predictors of nest success or that nesting in mistletoe may be maladaptive.

© 2018 Springer Science+Business Media, LLC, part of Springer Nature The high-frequency telescope for LiteBIRD is designed with refractive and reflective optics. In order to improve sensitivity, this paper suggests the new optical configurations of the HFT which have approximately 7 times larger focal planes than that of the original design. The sensitivities of both the designs are compared, and the requirement of anti-reflection (AR) coating on the lens for the refractive option is derived. We also present the simulation result of a sub-wavelength AR structure on both surfaces of silicon, which shows a band-averaged reflection of 1.1–3.2% at 101–448 GHz.

We present results from an analysis of all data taken by the BICEP2/Keck CMB polarization experiments up to and including the 2015 observing season. This includes the first Keck Array observations at 220 GHz and additional observations at 95 & 150 GHz. The $Q/U$ maps reach depths of 5.2, 2.9 and 26 $\mu$K$_{cmb}$ arcmin at 95, 150 and 220 GHz respectively over an effective area of $\approx 400$ square degrees. The 220 GHz maps achieve a signal-to-noise on polarized dust emission approximately equal to that of Planck at 353 GHz. We take auto- and cross-spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz. We evaluate the joint likelihood of the spectra versus a multicomponent model of lensed-$\Lambda$CDM+$r$+dust+synchrotron+noise. The foreground model has seven parameters, and we impose priors on some of these using external information from Planck and WMAP derived from larger regions of sky. The model is shown to be an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint $r_{0.05}, Comment: 23 pages, 23 figures, as accepted by PRL, data and figures available for download at http://bicepkeck.org/

Knowledge of seed bank status and dynamics is crucial for effective management of desirable and undesirable plant species in natural ecosystems. We studied the soil seed bank dynamics and soil nutrient concentrations in Lantana camara invaded and uninvaded patches at New Gada wetland in Harare, Zimbabwe. Soils were tested for pH, ammonium (NH 4 + ), nitrate (NO 3 − ), phosphorus (P), calcium (Ca), magnesium (Mg), sodium (Na) and potassium (K). We also assessed the soil seed bank density to a depth of 15 cm over varied altitudinal zones. Soil nutrient concentrations increased by a factor of 2.5 for Na, 3.1 for NH 4 + , 4.8 for Mg up to 8.5 for Ca with L . camara invasion. In contrast, L . camara invaded patches had a lower concentration of NO 3 − and P than uninvaded patches. Seed density significantly declined with both soil depth and slope with high seed density in the upper surface soil of the lower slopes of the wetland. The elevated soil nutrient concentrations along with a high soil seed bank density suggest that the wetland may still be susceptible to continued invasion by L . camara particularly on the lower slopes of the wetland. Thus, management and eradication efforts should focus on the areas that receive or trap the eroded soil seed bank.

Mistletoes have a major influence on nutrient dynamics in nutrient-poor ecosystems with potential to contribute to nutrient enrichment beneath tree-dominated patches. We studied the soil nutrient concentrations beneath four tree species with and without mistletoe infections. Effects of species and infection status on soil nutrient concentrations were tested using a general linear model (GLM). Soil nutrient concentrations differed with tree species, infection status and their interaction ( p Sclerocarya birrea and Diospyros mespiliformis , respectively. Soils beneath host trees had higher nutrient concentrations and were slightly alkaline than those beneath non-host trees. The concentration of soil nutrients increased by a factor ranging from 2.25 for N, 2.28 for P, 8.55 for Ca, 3.78 for Mg up to 39 for K. The increase in below-canopy soil fertility with mistletoe infection leads to an increase in the spatial heterogeneity of nutrient availability with potential to alter ecological factors such as species diversity and plant productivity. In conclusion, we suggest that nutrient enrichment in tree-dominated patches and associated increase in resource heterogeneity play an important role in determining ecosystem structure and function in semi-arid savanna.

Situations involving scale, rate, ratio, and proportion all require proportional reasoning (Ben-Chaim, Keret, & Ilany, 2007). Proportional reasoners can use multiplicative and relative thinking (in contrast to additive or absolute thinking), have a sense of co-variation, and can recognise situations of comparison requiring multiplicative reasoning (Fielding-Wells, Dole, & Makar, 2014). Not only is proportional reasoning essential for students to succeed in many mathematical contexts, it is also necessary in many other subject areas including art, geography, history, and science (Akatugba & Wallace, 2009). Proportional reasoning is also recognised as one of the most commonly used forms of mental computation in our daily lives and yet a large number of adults cannot reason proportionally (Lamon, 2012). Despite its recognition as a key element of numeracy, research shows that more focus is needed on helping students and teachers to develop the various aspects of proportional reasoning and the foundational concepts that underpin it (Kastberg, D’Ambrosio, & Lynch-Davis, 2012). This article describes research on using a string number line intervention to support children’s development of relative thinking and understanding of linear scale. The intervention proved effective for developing students’ understanding of concepts related to scale and relative thinking as well as their mathematical language. It also proved useful for teachers as a means of assessing and monitoring their students’ understanding and progress.

Improving middle years students’ engagement in mathematics and their numeracy skills has been an educational focus for many years. One approach is to utilise teachable moments in contexts beyond traditional mathematics classrooms that engage students in using mathematics in real world contexts, thereby developing their numeracy. This paper reports on student numeracy engagement through theatre staging workshops. Year 7 students were led by a professional stage manager to understand the role and the practicalities of stage management. While observing the workshops, it was realised that there were multiple opportunities to engage students in numeracy. Interview and observational data were collected to identify numeracy teaching opportunities and the nature of the mathematics involved. The workshops immersed students in a rich, real-world context that required them to apply mathematical knowledge and skills, especially in measurement, estimation and sequencing. The theatre context also gave the students opportunities to apply practical and logical reasoning skills that align with the Australian Curriculum general capability of numeracy. This paper provides teachers and schools engaging in contexts such as stage productions, an insight into how this creative focus presents a powerful real-life context that gives middle years students an imperative to use their mathematical knowledge and skills.