4,255 research outputs found
A TEX86 surface sediment database and extended Bayesian calibration
© The Author(s), 2015. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Scientific Data 2 (2015): 150029, doi:10.1038/sdata.2015.29.Quantitative estimates of past temperature changes are a cornerstone of paleoclimatology. For a number of marine sediment-based proxies, the accuracy and precision of past temperature reconstructions depends on a spatial calibration of modern surface sediment measurements to overlying water temperatures. Here, we present a database of 1095 surface sediment measurements of TEX86, a temperature proxy based on the relative cyclization of marine archaeal glycerol dialkyl glycerol tetraether (GDGT) lipids. The dataset is archived in a machine-readable format with geospatial information, fractional abundances of lipids (if available), and metadata. We use this new database to update surface and subsurface temperature calibration models for TEX86 and demonstrate the applicability of the TEX86 proxy to past temperature prediction. The TEX86 database confirms that surface sediment GDGT distribution has a strong relationship to temperature, which accounts for over 70% of the variance in the data. Future efforts, made possible by the data presented here, will seek to identify variables with secondary relationships to GDGT distributions, such as archaeal community composition
Language Characteristics of Individuals with Down Syndrome
On average, language and communication characteristics of individuals with Down syndrome (the most common genetic cause of intellectual disability) follow a consistent profile. Despite considerable individual variability, receptive language is typically stronger than expressive language, with particular challenges in phonology and syntax. We review the literature on language and literacy skills of individuals with Down syndrome, with emphasis on the areas of phonology, vocabulary, syntax, and pragmatics. We begin by describing the hearing, oral-motor, cognitive, social, and prelinguistic and early nonverbal communication characteristics of individuals with Down syndrome. We conclude with a discussion of clinical implications and research directions
A review of methods used to kill laboratory rodents: issues and opportunities
Rodents are the most widely used species for scientific purposes. A critical pre-requisite of their use, based on utilitarian ethical reasoning, is the provision of a humane death when necessary for scientific or welfare grounds. Focussing on the welfare challenges presented by current methods, we critically evaluate the literature, consider emerging methodologies that may have potential for refinement and highlight knowledge gaps for future research. The evidence supports the conclusion that scientists and laboratory personnel should seek to avoid killing laboratory rodents by exposing them to carbon dioxide (CO2), unless exploiting its high-throughput advantage. We suggest that stakeholders and policymakers should advocate for the removal of CO2 from existing guidelines, instead making its use conditionally acceptable with justification for additional rationale for its application. With regards to physical methods such as cervical dislocation, decapitation and concussion, major welfare concerns are based on potential inaccuracy in application and their susceptibility to high failure rates. There is a need for independent quality-controlled training programmes to facilitate optimal success rates and the development of specialist tools to improve outcomes and reliability. Furthermore, we highlight questions surrounding the inconsistent inclusion criteria and acceptability of physical methods in international regulation and/or guidance, demonstrating a lack of cohesion across countries and lack of a comprehensive ‘gold standard’ methodology. We encourage better review of new data and championing of open access scientific resources to advocate for best practice and enable significant changes to policy and legislation to improve the welfare of laboratory rodents at killing
A decade on where is the UK poultry industry for emergency on-farm killing?
Millions of poultry are farmed intensively every year across the United Kingdom (UK) to produce both meat and eggs. There are inevitable situations that require birds to be emergency killed on farm to alleviate pain and suffering. In Europe and the UK, emergency methods are regulated by the European Council Regulation (EC) No. 1099/2009 and The Welfare of Animals at the Time of Killing Regulations (England 2015; Scotland 2012; Wales and Northern Ireland 2014). Cervical dislocation has been reported to be the most widely used method prior to these legislative changes which took place from 1 January 2013. Based on limited scientific evidence and concern for bird welfare, these legislative changes incorporated restrictions based on bird weight for both manual (≤3 kg) and mechanical (≤5 kg) cervical dislocation, and introduced an upper limit in the number of applications for manual cervical dislocation (up to 70 birds per person per day). Furthermore, it removed methods which showed evidence of crushing injury to the neck. However, since legal reform new scientific evidence surrounding the welfare consequences of cervical dislocation and the development of novel methods for killing poultry in small numbers on farm have become available. Whether the UK poultry industry have adopted these novel methods, and whether legislative reform resulted in a change in the use of cervical dislocation in the UK remains unknown. Responses from 215 respondents working across the UK poultry industry were obtained. Despite legal reform, manual cervical dislocation remains the most prevalent method used across the UK for killing poultry on farm (used by 100% of farms) and remains the preferred method amongst respondents (81.9%). The use of alternative methods such as Livetec Nex® and captive bolt guns were available to less than half of individuals and were not frequently employed for broilers and laying hens. Our data suggests there is a lack of a clear alternative to manual cervical dislocation for individuals working with larger species and a lack of gold standard methodology. This risks bird welfare at killing and contributes to inconsistency across the industry. We suggest providing stakeholders with practical alternatives prior to imposing legislative changes and effective knowledge transfer between the scientific community and stakeholders to promote positive change and protect bird welfare
Humane mechanical methods for killing poultry on-farm
Worldwide, an estimated 9.1 billion birds may need to be killed on farm each year. As of January 2013 the use of manual cervical dislocation (MCD) as a killing method for poultry on-farm has been heavily restricted through new EU legislation (EC 1099/2009) on the Welfare of Animals at the Time of Killing, following reported welfare concerns. The method by which birds are killed on farm is crucial to poultry welfare on a large scale. The overall aim of this project was to design a mechanical device conforming to the new legislation to kill poultry humanely on-farm and provide a competitive replacement for MCD.
Following a survey and a literature review, four mechanical devices were designed and prototyped: Modified Armadillo (MARM); Modified Pliers (MPLI); Modified Rabbit Zinger (MZIN) and a Novel mechanical cervical dislocation glove (NMCD). The devices were tested for killing efficacy in three laboratory experiments, assessing their performance in poultry cadavers (Study 1), anaesthetised birds (Study 2) and live conscious birds (Study 3). The reliability and welfare impact of the devices, along with comparisons with a control method (MCD) were evaluated via post-mortem analysis, reflex and behaviour durations, and characteristics of electroencephalography (EEG) analysis. Due to consistently high kill success rates and rapid loss of reflexes, as well as short durations of EEG activity indicating consciousness across three laboratory experiments, the NMCD device was shown to have the most promise as a mechanical device to be used as an alternative to MCD for poultry stock-workers and keepers. The final experiment explored the user-reliability and practicality of the NMCD device in two relevant commercial environments (a layer hen farm and a broiler farm). When applied by multiple users, the NMCD device did not match the killing performance of MCD, however it did show promise and the study highlighted the need for further refinement in the training protocol in order to encompass the wide variation in MCD techniques and experience.
The result of this project is a novel on-farm mechanical killing device, which shows great potential in laboratory experiments and competed with the traditional MCD method in commercial environments. Further training refinements are required in order to develop the device into a marketable product which any individual could purchase and use as a humane method for killing poultry
Comparison of novel mechanical cervical dislocation and a modified captive bolt for on-farm killing of poultry on behavioural reflex responses and anatomical pathology
An alternative emergency method for killing poultry on-farm is required following European legislation changes (EU 1099/2009), which heavily restricts the use of manual cervical dislocation. This study investigated the kill efficacy of two mechanical methods that conform to the new legislation: (i) a novel mechanical cervical dislocation device; and (ii) a modified captive-bolt device (Rabbit Zinger™) and manual cervical dislocation (the control). Killing treatments were applied to broilers and layers at two stages of production (broilers: 2–3 and 5 weeks of age; layers: 12–13 and 58–62 weeks), with a total of 180 birds. Latency to abolition of cranial and behavioural reflexes, as well as post mortem analysis of the physiological damage produced, were used to estimate time to unconsciousness and assess kill efficacy. The novel mechanical cervical dislocation device was reliable and a practical method for killing poultry on-farm (100% kill success), with the majority of cranial reflexes showing no significant differences between interval mean durations across killing methods (eg nictitating membrane [mean = 0.7–3.3 s], and rhythmic breathing [mean = 0.0–0.3 s]), however for jaw tone and pupillary reflex, the modified Rabbit Zinger™ had significantly shorter interval mean durations compared to the control and mechanical cervical dislocation device (mean differences: jaw tone = ∼8 s; pupillary = ∼38 s). The novel mechanical cervical dislocation device resulted in consistent anatomical damage to the birds (eg high dislocation of the neck and severing of the spinal cord) compared to the manual method, despite both having 100% success rate, while the modified Rabbit Zinger™ was difficult to operate and resulted in varied anatomical damage. The novel mechanical cervical dislocation device showed promise as a replacement kill method on-farm for poultry
Structure of the ATP synthase from Mycobacterium smegmatis provides targets for treating tuberculosis.
The structure has been determined by electron cryomicroscopy of the adenosine triphosphate (ATP) synthase from Mycobacterium smegmatis This analysis confirms features in a prior description of the structure of the enzyme, but it also describes other highly significant attributes not recognized before that are crucial for understanding the mechanism and regulation of the mycobacterial enzyme. First, we resolved not only the three main states in the catalytic cycle described before but also eight substates that portray structural and mechanistic changes occurring during a 360° catalytic cycle. Second, a mechanism of auto-inhibition of ATP hydrolysis involves not only the engagement of the C-terminal region of an α-subunit in a loop in the γ-subunit, as proposed before, but also a "fail-safe" mechanism involving the b'-subunit in the peripheral stalk that enhances engagement. A third unreported characteristic is that the fused bδ-subunit contains a duplicated domain in its N-terminal region where the two copies of the domain participate in similar modes of attachment of the two of three N-terminal regions of the α-subunits. The auto-inhibitory plus the associated "fail-safe" mechanisms and the modes of attachment of the α-subunits provide targets for development of innovative antitubercular drugs. The structure also provides support for an observation made in the bovine ATP synthase that the transmembrane proton-motive force that provides the energy to drive the rotary mechanism is delivered directly and tangentially to the rotor via a Grotthuss water chain in a polar L-shaped tunnel
Building the Capacity of Classroom Teachers as Extenders of Nutrition Education through Extension: Evaluating a Professional Development Model
Utilizing teachers as extenders may maximize the reach of Extension nutrition education programs; however, there is a need to identify effective professional development (PD) strategies to ensure quality implementation. Lesson study is a PD model that demonstrated improvements in school teachers’ self-efficacy and knowledge in various disciplines. In this study, fourth-grade teachers at two schools delivered nutrition education in their classrooms. Lesson study was examined to improve self-efficacy, content knowledge, and use of inquiry-based teaching strategies. While teachers at one school followed the lesson study model, teachers at the other school did not. Teachers reported time, resources, and funding were barriers to using lesson study and implementing the curriculum. Teachers who reported teaching nutrition previously declined in self-efficacy and knowledge. It is possible that they underestimated what would be required to teach this curriculum, resulting in a higher pre-test rating of self-efficacy compared to ratings after teaching the curriculum. This shift may have affected their motivation and willingness to participate fully in the lesson study process. Increasing teacher access to content experts during PD may improve teacher selfefficacy. Providing additional support and materials may increase the likelihood that teachers participate as extenders of Extension nutrition education programs
Combination of Immunotherapy and Radiotherapy-The Next Magic Step in the Management of Lung Cancer?
none4sinoneHendriks L.E.L.; Menis J.; De Ruysscher D.K.M.; Reck M.Hendriks, L. E. L.; Menis, J.; De Ruysscher, D. K. M.; Reck, M
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