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The escape fraction of Lyman-continuum (LyC) photons ($f_{esc}$) is a key parameter for determining the sources of cosmic reionization at $z\geq 6$. At these redshifts, owing to the opacity of the intergalactic medium, the LyC emission cannot be measured directly. However, LyC leakers during the epoch of reionization could be identified using indirect indicators that have been extensively tested at low and intermediate redshifts. These include a high [OIII]/[OII] flux ratio, high star-formation surface density, and compact sizes. In this work, we present observations of 29 $4.5 \leq z \leq 8$ gravitationally lensed galaxies in the Abell 2744 cluster field. From a combined analysis of JWST-NIRSpec and NIRCam data, we accurately derived their physical and spectroscopic properties: our galaxies have low masses $(\log(M_\star)\sim 8.5)$, blue UV spectral slopes ($\beta \sim -2.1$), compact sizes ($r_e \sim 0.3-0.5$ kpc), and high [OIII]/[OII] flux ratios. We confirm that these properties are similar to those characterizing low-redshift LyC leakers. Indirectly inferring the fraction of escaping ionizing photons, we find that more than 80% of our galaxies have predicted $f_{esc}$ values larger than 0.05, indicating that they would be considered leakers. The average predicted $f_{esc}$ value of our sample is 0.12, suggesting that similar galaxies at $z\geq 6$ have provided a substantial contribution to cosmic reionization., Comment: Accepted for publication in the 4. Extragalactic astronomy section of A&A, 12 pages, 8 figures

The GLASS-JWST Early Release Science (hereafter GLASS-JWST-ERS) Program will obtain and make publicly available the deepest extragalactic data of the ERS campaign. It is primarily designed to address two key science questions, namely, “what sources ionized the universe and when?” and “how do baryons cycle through galaxies?”, while also enabling a broad variety of first look scientific investigations. In primary mode, it will obtain NIRISS and NIRSpec spectroscopy of galaxies lensed by the foreground Hubble Frontier Field cluster, Abell 2744. In parallel, it will use NIRCam to observe two fields that are offset from the cluster center, where lensing magnification is negligible, and which can thus be effectively considered blank fields. In order to prepare the community for access to this unprecedented data, we describe the scientific rationale, the survey design (including target selection and observational setups), and present pre-commissioning estimates of the expected sensitivity. In addition, we describe the planned public releases of high-level data products, for use by the wider astronomical community.

We present an observational study of the luminous red nova (LRN) AT 2021biy in the nearby galaxy NGC 4631. The field of the object was routinely imaged during the pre-eruptive stage by synoptic surveys, but the transient was detected only at a few epochs from ∼231 days before maximum brightness. The LRN outburst was monitored with unprecedented cadence both photometrically and spectroscopically. AT 2021biy shows a short-duration blue peak, with a bolometric luminosity of ∼1.6 × 1041 erg s−1, followed by the longest plateau among LRNe to date, with a duration of 210 days. A late-time hump in the light curve was also observed, possibly produced by a shell-shell collision. AT 2021biy exhibits the typical spectral evolution of LRNe. Early-time spectra are characterised by a blue continuum and prominent H emission lines. Then, the continuum becomes redder, resembling that of a K-type star with a forest of metal absorption lines during the plateau phase. Finally, late-time spectra show a very red continuum (TBB ≈ 2050 K) with molecular features (e.g., TiO) resembling those of M-type stars. Spectropolarimetric analysis indicates that AT 2021biy has local dust properties similar to those of V838 Mon in the Milky Way Galaxy. Inspection of archival Hubble Space Telescope data taken on 2003 August 3 reveals a ∼20 M⊙ progenitor candidate with log (L/L⊙) = 5.0 dex and Teff = 5900 K at solar metallicity. The above luminosity and colour match those of a luminous yellow supergiant. Most likely, this source is a close binary, with a 17–24 M⊙ primary component.

Microlenses with typical stellar masses (a few ${\rm M}_{\odot}$) have traditionally been disregarded as potential sources of gravitational lensing effects at LIGO/Virgo frequencies, since the time delays are often much smaller than the inverse of the frequencies probed by LIGO/Virgo, resulting in negligible interference effects at LIGO/Virgo frequencies. While this is true for isolated microlenses in this mass regime, we show how, under certain circumstances and for realistic scenarios, a population of microlenses (for instance stars and remnants from a galaxy halo or from the intracluster medium) embedded in a macromodel potential (galaxy or cluster) can conspire together to produce time delays of order one millisecond which would produce significant interference distortions in the observed strains. At sufficiently large magnification factors (of several hundred), microlensing effects should be common in gravitationally lensed gravitational waves. We explore the regime where the predicted signal falls in the frequency range probed by LIGO/Virgo. We find that stellar mass microlenses, permeating the lens plane, and near critical curves, can introduce interference distortions in strongly lensed gravitational waves. For those lensed events with negative parity, (or saddle points, never studied before in the context of gravitational waves), and that take place near caustics of macromodels, they are more likely to produce measurable interference effects at LIGO/Virgo frequencies. This is the first study that explores the effect of a realistic population of microlenses, plus a macromodel, on strongly lensed gravitational waves., Comment: 16 pages

aGlobal Plant Clinic, CABI, Bakeham Lane, Egham, Surrey, TW20 9TY, UK; b Agricultural Advisory Society, House # 8/7 (Ground Floor), Block-B, Lalmatia, Dhaka-1207, Bangladesh; and c PROINPA, Av. Meneces s/n Km.4 (zona EI Paso), Cochabamba, Bolivia All peoples have names for and knowledge of plants, animals and other things in the real world. An ethnopathology (or, more strictly, ‘ethnophytopathology’) ‐ study in Bangladesh, Uganda and Bolivia revealed that smallholder farmers label plant health problems with meaningful names. A local name for a plant health problem typically has two kinds of meaning. The first is a literal translation of the name, often a kind of shorthand description of the symptom. The second and most important kind of meaning is the denotative meaning (the thing in the real world which the name actually refers to). Local words for plant health problems often label the symptom rather than the actual disease. This is logical, since smallholders cannot observe microscopic causal organisms. Local concepts for plant health problems do not necessarily classify the natural world in exactly the same way that scientists do, yet local terms for plant health problems are still meaningful. It is not clear if folk classifications of plant health problems are phylogenetic classifications (e.g. ‘mammals’ vs. ‘fish’) or ecological (e.g. ‘seafood’ vs. ‘meat and poultry’). Cross-culturally, local knowledge recognizes that plants are alive, and that they may be ill or healthy, perhaps in analogy with human health.

Mimosa pudica is a perennial plant, widespread in tropical and sub-tropical regions. Known in English as the sensitive plant because of its rapid leaf movements when touched, it is a serious weed in managed grasslands and plantation crops such as coffee, tea and oil palm (Waterhouse, 1993). It is also a popular ornamental plant with medicinal properties. On Samosir Island in North Sumatera, M. pudica is a common invasive speciesof crops and waste areas. In October 2007, leaf yellowing, little leaf and proliferation ofaxillary shootswereobserved in plants from roadsides and in crop fields around Pangururan village. Leaf and stem samples were collected from three plants with symptoms and one symptomless plant. TotalDNAwasextractedandusedasatemplate inanestedPCRassaywith phytoplasma universal 16S rRNA gene primers R16F2m ⁄ R1 and fU5 ⁄ rU3. All samples with symptoms yielded PCR products of expected size (~880 bp), and identical HaeIII, RsaI and AluI RFLP profiles. No PCR products were produced with DNA from the symptomless plant. Nested PCRampliconswerepurifiedanddirectlysequenced(http://www.dnaseq.co.uk). The 16S rDNA sequences were 100% identical, and deposited in GenBank (Accession No. EU273883). BLAST comparisons of the M. pudica phytoplasma 16S rDNA sequence yielded the highest identity (99%) withthoseofmembersofgroup16SrI, ‘CandidatusPhytoplasmaasteris’. Phytoplasmas have been found previously in Indonesia associated with diseases such as legume witches’ broom (Roechan et al., 1978), chilli and tamarillo diseases (Harling et al., 2009) and Kalimantan coconut wilt (Warokka et al., 2006), however, none of these have been from ‘Candidatus Phytoplasma asteris’. This is the first record of a yellows disease on M. pudica worldwide, its association with a phytoplasma and identification of ‘Ca. Phytoplasma asteris’ in Indonesia.

Fifty respondents were surveyed using a recently developed questionnaire designed to evaluate the educational needs of the users of self-monitoring blood pressure apparatus. The categories evaluated included each subject's background and family health history, general knowledge about blood pressure, lifestyle factors affecting blood pressure, and factors affecting the measurement of blood pressure, as well as questions about owning a home monitor and recalibration and maintenance factors. The results indicate considerable disparity between the subjects' levels of knowledge about lifestyle factors affecting blood pressure and the subjects' knowledge of factors essential to accurate self-monitoring of blood pressure. The implications of and need for the design of educational training protocols are discussed.

In October 2008, coconut plantations in the villages of Tobenam, Pupun and Dugumor, located in the Bogia district of the Madang Province in Papua New Guinea (PNG), exhibited lethal yellowing-like symptoms in both newly planted and old …

In 2006, citrus fruit and leaves affected by dark brown lesions were noticed in orchards around Makeni in central Sierra Leone . The problem was considered widespread in the area by officers of the local station of the Ministry of…

Bean ( Phaseolus vulgaris ) is one of the most important vegetables in Sri Lanka. In 1999, a new bean disease was reported from the town of Balangoda, Sri Lanka. Symptoms included a bright yellow mosaic pattern on the leaves, rugosity,…

In November 2006, researchers at the Ministry of Agriculture, Forestry and Fisheries, first observed symptoms of witches’ broom on cacao trees in the Union Vale, La Dauphine, and Robot estates in Saint Lucia. The disease has since been found in other smallholder plots throughout the island. Estate managers report up to 50% of the cacao trees are infected. Diseased trees have dense, slightly curved proliferations of shoots with shortened internodes (witches’ brooms), arising from the lateral buds. Other symptoms include leaf necrosis, distortion and enlargement of the leaf lamina and veins, and stem swellings. Brooms in cacao are characteristic of infection by the fungus Moniliophthora perniciosa (formerly Crinipellis perniciosa ). In May 2007, samples of older, well-dried brooms were sent to the Global Plant Clinic, UK for confirmation of the pathogen. Aggregations of white saprotrophic hyphae were seen under the bark, which under microscopic examination revealed clamp connections that are characteristic of M. perniciosa . A more definitive morphological identification was obtained by inducing the fungus to produce basidiocarps. Brooms were suspended in a cabinet and subjected to a daily cycle of wetting and drying. The subsequent basdiocarps were pink, tinged with crimson and had a delicate pileus that was radially grooved with fluted edges. Fungal mycelia isolated directly from the brooms were also tested using molecular characterisation. The ITS regions of the rDNA was amplified and sequenced with fungal specific primers ITS6 (Cooke & Duncan, 1997) and ITS4 (White et al ., 1990). The sequence obtained (GenBank Accession No. EU861393) showed greater than 99% homology to 16 strains of this species held in the GenBank database. Witches’ broom of cacao is endemic to the Amazon basin region of South America, but has spread to plantations in the Americas and several Caribbean islands. This fungus can cause up to 90% pod losses and is considered to be one of the main limiting factors for cacao production in South America and the Caribbean islands (Griffith et al ., 1994). The disease has previously been recorded from the Caribbean islands of the Dominican Republic, Grenada, St Vincent and Grenadines and Trinidad and Tobago, but this is the first confirmed report of witches’ broom in cacao from Saint Lucia.

To characterize ventilatory responses to bronchoconstriction during sleep and to assess the effect of prior sleep deprivation on ventilatory and arousal responses to bronchoconstriction, bronchoconstriction was induced in eight asthmatic subjects while they were awake, during normal sleep, and during sleep after a 36-h period of sleep deprivation. Each subject was bronchoconstricted with increasing concentrations of aerosolized methacholine while ventilatory patterns and lower airway resistance (Rla) were continually monitored. The asthmatic patients maintained their minute ventilation as Rla increased under all conditions, demonstrating a stable tidal volume with a mild increase in respiratory frequency. Inspiratory drive, as measured by occlusion pressure (P0.1), increased progressively and significantly as Rla increased under all conditions (slopes of P0.1 vs. Rla = 0.249, 0.112, and 0.154 for awake, normal sleep, and sleep after sleep deprivation, respectively, P less than 0.0006). Chemostimuli did not appear to contribute significantly to the observed increases in P0.1. Prior sleep deprivation had no effect on ventilatory and P0.1 responses to bronchoconstriction but did significantly raise the arousal threshold to induced bronchoconstriction. We conclude that ventilatory responses to bronchoconstriction, unlike extrinsic loading, are not imparied by the presence of sleep, nor are they chemically mediated. However, prior sleep deprivation does increase the subsequent arousal threshold.

The deposition of vapors on electrostatically suspended dust has been studied through the construction of a laboratory‐scale coating unit suitable for depositing coatings of high‐melting point vapors (up to 1600 °C) on dispersed metal powders in a vacuum. Following a brief discussion of electrodispersion, the physical effect by which electrostatic suspensions may be generated, the construction and use of a laboratory coating unit is described. The equipment, which is housed in a vacuum enclosure at

This study provides a comparison of self-measurement blood pressure devices, with respect to the standards published by the American National Standards Institute/Association for the Advancement of Medical Instrumentation and statements from the American Heart Association and the National High Blood Pressure Education Program. The results show a wide disparity among the recommendations of select committees, on issues of education and compliance and on design features of this instrumentation. Procedural problems in determining compliance in this study highlight the need for improved objectivity in statements in national standards and for improved awareness of those statements by manufacturers.