21 research outputs found

    On the Spiral Structure of the Milky Way Galaxy

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    We consider the possible pattern of the overall spiral structure of the Galaxy, using data on the distribution of neutral (atomic), molecular, and ionized hydrogen, on the base of the hypothesis of the spiral structure being symmetric, i.e. the assumption that spiral arms are translated into each other for a rotation around the galactic center by 180{\deg} (a two-arm pattern) or by 90{\deg} (a four-arm pattern). We demonstrate that, for the inner region, the observations are best represented with a four-arm scheme of the spiral pattern, associated with all-Galaxy spiral density waves. The basic position is that of the Carina arm, reliably determined from distances to HII regions and from HI and H2 radial velocities. This pattern is continued in the quadrants III and IV with weak outer HI arms; from their morphology, the Galaxy should be considered an asymmetric multi-arm spiral. The kneed shape of the outer arms that consist of straight segments can indicate that these arms are transient formations that appeared due to a gravitational instability in the gas disk. The distances between HI superclouds in the two arms that are the brightest in neutral hydrogen, the Carina arm and the Cygnus (Outer) arm, concentrate to two values, permitting to assume the presence of a regular magnetic field in these arms.Comment: 21 pages, 14 fugures; accepted for publication in Astronomichesky Journal (Astron. Rep.

    Investigation of tutin, a naturally-occurring plant toxin, as a novel, culturally-acceptable rodenticide in New Zealand

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    He nui nga mātauranga a te Māori (Ngai Tūhoe) e pā ana ki nga momo hua tāokeoke (Toxins) etaea ana te whakarite hei rauemi tāwai i ngā riha kīrearea, pērā anō ki nga whiu takarangi o te tāoke 1080. I whakamātauhia e matou i nga ira tāoke o roto o te hua Tutu, ki rō taiwhanga pūtaiao. Mā te wero atu ki tētahi kiore (Norway Rat) i hua mai ngā mohiotanga o te nui me te momo o ngā tāokeoke kei roto i tēnei miro Māori, me te āhua o tēnei tāoke kia mau-rohā tonu tōna tuku whakahemo (Humaneness). Kei tua o te 55 mg kg⁻¹neke atu, te ine i tūtuki pai ai nga tāhawahawatanga o te miro Tutu, ā, e mau-roha tonu ana te kōhurutanga o te r iha. Ko te whakatau kia kawea atu tēnei kaupapa ki nga ahurewa rangahau e taea ai te waihanga i tētahi mōunu tāokeoke, kia whakamātauria ki rō ngāhere. Hei tāpiritanga ki tēnei, he roa rawa te wā e pakari ai te whanaketanga mai o tētahi tākoe e rerekē ana ki te 1080, anō nei, mā ngā kawenga o te mātauranga Māori ki tēnei take e whanake tika ai te kaupapa nei. New Zealand has many introduced mammalian species that are managed as pests of conservation and/or economic importance, including four rodent species. Vertebrate pesticides are the most important rodent management tool, largely dominated by anticoagulants such as brodifacoum, and by the metabolic disruptor, Compound 1080. There has been considerable opposition to these pesticides, primarily based on concerns about environmental persistence and non-target effects; Maori have been particularly vocal in opposition. Maori have place-based knowledge about naturally-occurring plant toxins that could be used as culturally-acceptable alternatives to existing rodenticides. In the context of the research presented here, the term ‘culturally-acceptable’ refers to new pest control options that have been co-designed with Matauranga Maori experts that inherently include Maori ways of thinking, being, and acting. Tuhoe researchers in our study wanted to pursue the most promising natural toxic compound found in native plants as a suitable alternative to current vertebrate pesticides. Therefore, we undertook an oral gavage trial to assess the toxicity of tutin, the toxin active in tutu (Coriaria arborea), to the Norway rat, (Rattus norvegicus). Tutin was toxic to this species at a dose of 55 mg kg⁻¹, with a quick, humane death compared to other existing rodenticides. At a dose rate of 55 mg kg⁻¹, all animals of both sexes died within an hour, and once neurological poisoning symptoms commenced these animals were unconscious within 5-10 minutes. We conclude it is warranted to take the next logical research step, which is to prove whether this dose rate would be technically attainable in the field. Although for now New Zealand remains reliant on 1080 and anti-coagulants for mammalian pest control, efforts should continue to develop more targeted toxins and delivery systems. We recommend incorporating Matauranga Maori to identify alternative control tools that could lead to more culturally acceptable pest control

    Blood pressure self-monitoring in pregnancy (BuMP) feasibility study; a qualitative analysis of women's experiences of self-monitoring

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    Background Hypertensive disorders in pregnancy are a leading cause of maternal and fetal morbidity worldwide. Raised blood pressure (BP) affects 10% of pregnancies worldwide, of which almost half develop pre-eclampsia. The proportion of pregnant women who have risk factors for pre-eclampsia (such as pre-existing hypertension, obesity and advanced maternal age) is increasing. Pre-eclampsia can manifest itself before women experience symptoms and can develop between antenatal visits. Incentives to improve early detection of gestational hypertensive disorders are therefore strong and self-monitoring of blood pressure (SMBP) in pregnancy might be one means to achieve this, whilst improving women’s involvement in antenatal care. The Blood Pressure Self-Monitoring in Pregnancy (BuMP) study aimed to evaluate the feasibility and acceptability of SMBP in pregnancy. Methods To understand women’s experiences of SMBP during pregnancy, we undertook a qualitative study embedded within the BuMP observational feasibility study. Women who were at higher risk of developing hypertension and/or pre-eclampsia were invited to take part in a study using SMBP and also invited to take part in an interview. Semi-structured interviews were conducted at the women’s homes in Oxfordshire and Birmingham with women who were self-monitoring their BP as part of the BuMP feasibility study in 2014. Interviews were conducted by a qualitative researcher and transcribed verbatim. A framework approach was used for analysis. Results Fifteen women agreed to be interviewed. Respondents reported general willingness to engage with monitoring their own BP, feeling that it could reduce anxiety around their health during pregnancy, particularly if they had previous experience of raised BP or pre-eclampsia. They felt able to incorporate self-monitoring into their weekly routines, although this was harder post-partum. Self-monitoring of BP made them more aware of the risks of hypertension and pre-eclampsia in pregnancy. Feelings of reassurance and empowerment were commonly reported by the women in our sample
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