Molecular ions in L1544. I. Kinematics

We have mapped the dense dark core L1544 in H13CO+(1-0), DCO+(2-1), DCO+(3-2), N2H+(1-0), NTH+(3-2), N2D+(2-1), N2D+(3-2), C18O(1-0), and C17O(1-0) using the IRAM 30-m telescope. We have obtained supplementary observations of HC18O+(1-0), HC17O+(1-0), and D13CO+(2-1). Many of the observed maps show a general correlation with the distribution of dust continuum emission in contrast to C18O(1-0) and C17O(1-0) which give clear evidence for depletion of CO at positions close to the continuum peak. In particular N2D+(2-1) and (3-2) and to a lesser extent N2H+(1-0) appear to be excellent tracers of the dust continuum. We find that the tracers of high density gas (in particular N2D+) show a velocity gradient along the minor axis of the L1544 core and that there is evidence for larger linewidths close to the dust emission peak. We interpret this using the model of the L1544 proposed by Ciolek & Basu (2000) and by comparing the observed velocities with those expected on the basis of their model. The results show reasonable agreement between observations and model in that the velocity gradient along the minor axis and the line broadening toward the center of L1544 are predicted by the model. This is evidence in favour of the idea that amipolar diffusion across field lines is one of the basic processes leading to gravitational collapse. However, line widths are significantly narrower than observed and are better reproduced by the Myers & Zweibel (2001) model which considers the quasistatic vertical contraction of a layer due to dissipation of its Alfvenic turbulence, indicating the importance of this process for cores in the verge of forming a star.Comment: 24 pages, 9 figures, to be published in Ap

Inventory of novel approaches to seed quality assurance mechanisms for vegetatively propagated crops (VPCs) in seven African countries

This paper provides an inventory of novel approaches to and mechanisms for quality assurance of the seeds of vegetatively produced crops (VPCs). It explores to what extent seven African countries (Ethiopia, Kenya, Malawi, Nigeria, Tanzania, Uganda and Zambia) are decentralising and integrating VPC seed systems, in terms of regulations governing the sector, methods of seed production, and methods of seed inspection and certification. It consolidates existing data and presents new data on decentralised seed quality assurance (SQA) approaches for VPCs in these seven selected countries. It makes relevant information readily available for policy dialogue on appropriate and inclusive SQA approaches, by providing an assessment of (i) the extent to which SQA has been decentralised, i.e., the extent to which third-party accredited inspectors have been deployed; (ii) countries’ use of e-certification platforms; (iii) the involvement of seed producer groups and cooperatives in SQA; and (iv) any novel approaches to disease diagnostics or other relevant aspects of SQA. The paper uses different, appropriately sequenced methods to ensure the different methods complement each other to offset the disadvantages of each method. These include a comprehensive literature review, an online survey, and key informants’ virtual interviews. These are complemented by expert interviews, especially with both IITA and CIP experts based in Tanzania, Uganda, and Ethiopia plus one CIP expert with overall knowledge of the project countries in Africa. Based on an online survey completed by officials from regulatory agencies from eight countries, and follow-up interviews with seed certification officials and researchers in the seed sector, the paper finds that almost all studied countries have some sort of decentralised seed production system in place, allowing large-scale companies, medium-semi-commercial companies and small holder farmers opportunities to produce both quality declared and certified seeds. These decentralised seed production systems may be regarded as novel, in that they deviate from the standard seed system practices proposed at international level, which focus on enforcing certified seed production. Further, the novelty is based on different countries adopting different processes because of different local constraints and different government/political structures. Such novelty is necessary in the African context of, inter alia, poor infrastructure for transporting VPC seeds long distance and limited technical skills for certifying seed. The innovative approaches chosen by these African countries are suitable for VPC seeds like those of cassava, sweetpotato, bananas, yams and potato – all of which have bulky and perishable planting materials. The paper shows that it is possible to make decentralised VPC seed systems a reality in the right circumstances, and that in some cases countries have already made strides in doing so. However, several gaps exist in different countries, all of which need to be addressed. They include problems such as (i) legislation and regulations not specifically considering the quality assurance requirements of VPCs; (ii) shortages of trained staff throughout the system, but especially in far-flung areas; (iii) unavailable or inadequate training materials and handbooks; (iv) inadequate resources at local level, including support for inspection equipment and resources (e.g., vehicles); (v) poor monitoring and administration capacity in farmers’ cooperatives/associations; and (vi) poor consideration given to gender empowerment. Each of these and other issues are discussed throughout the report and in the recommendations at the end of the document. Stakeholders in the VPC sectors need to address key challenges facing VPC seed producers and users such as the lack of specific regulations for VPCs and standards, especially in the countries which are either still developing such standards and regulations, or entirely do not have such tools in place. The absence of crop specific guidelines and standard operating procedures result in (i) low capacity to produce quality VPC seed, (ii) poor storage and handling facilities for seed and (iii) inadequate experience, technical skills and training among the seed inspectors and certifying officials from state seed regulatory agencies, especially lack of staff specialised in certifying VPCs. Simple, flexible and less bureaucratic systems are much more desirable for developing countries, even while countries must maintain a focus on quality control and quality assurance mechanisms within the legal provisions of seed laws, including those of novel approaches (Loch and Boyce, 2001). Quality control and quality assurance are important preconditions for ensuring the availability of planting materials and for piloting novel approaches such as decentralised seed production and quality control approaches. It is thus important for countries to mainstream and scale up sustainable quality assurance systems that work by establishing context-appropriate seed regulatory frameworks. While individual farmers, farm-based associations, farmer cooperatives and private companies have invested and continue to invest in production of VPC seeds, public investments in this sector are needed to realise wider system change and impact. Because VPC seeds are bulky, perishable and have high disease risks, many seed companies are not interested in these crops. Therefore, is important to secure political buy-in for decentralised VPC production and devolved VPC seed inspection so that states are encouraged to invest in supporting regulatory agencies and decentralised offices to deliver their services efficiently and effectively. In turn, this will allow farmers to secure the extension services they require. To ensure scalability and sustainability of novel approaches like the decentralisation of seed production and quality assurance, piloted initiatives must be sustained, including (i) for capacity development; (ii) providing adequate resources (competent personnel, funding and the necessary technologies like electronic platforms); and (iii) more importantly, the presence of an entrenched policy, legal and institutional framework that is implemented on the ground. As part of the remedy for these challenges, the paper recommends that engaged stakeholders in the VPCs sector provide targeted training of seed inspectors. In many countries, seed standards for VPCs and provisions in the law were designed based on the experiences of grain (maize) seeds, which have significant differences with VPCs. Therefore, seed inspectors need training for inspection of VPCs (i.e. varietal identification, crop specific pests and diseases). This can be complemented by capacity development efforts at different levels; for example, (i) training extension officers to undertake inspections and how to use relevant equipment (including any ICT devices); (ii) training seed producer associations on technical and governance/administrative aspects for ensuring equity, accountability and monitoring; and (iii) training seed producers to inspect their own seed and fields. Countries need to establish and scale up seed producers’ associations. In countries where seed producer associations are in place, they have shown to be cost-effective by mobilising fellow seed producers who need seed inspections to pay inspectors as a group instead of as individuals. This has in turn also driven the demand for inspection from the relevant authorities, because inspection activities such as these generate income for government agencies. With associations in place, it is possible to help seed producers and farmers to identify markets for both seed and produce, to create a virtuous cycle whereby producers buy improved seed because they have a market for their improved produce. Finally, stakeholders need to implement or scale up e-certification platforms like SeedTrackerTM to reduce the burden and costs associated with manual and physical activities related to seed inspection and certification. Where ICT systems such as SeedTrackerTM have not been implemented, roll these out in all countries, ensuring both that they are suitable for each country’s specific needs, and that they align with regional and international seed policy. In countries like Nigeria and Tanzania where SeedTrackerTM is in place, it is imperative that most of these tools are improved to address the current limitations. Meanwhile, achievements – including the use of successful ICT tools – need to be promoted through regular communication and dialogue at all levels, including between farmers, seed producers and breeders (about the preferred traits for improved varieties and any challenges farmers are facing), and between stakeholders (to ensure alignment on the goals of seed quality assurance, how to ensure quality, and how to address problems)

Alpha kinase 3 signaling at the M-band maintains sarcomere integrity and proteostasis in striated muscle

Muscle contraction is driven by the molecular machinery of the sarcomere. As phosphorylation is a critical regulator of muscle function, the identification of regulatory kinases is important for understanding sarcomere biology. Pathogenic variants in alpha kinase 3 (ALPK3) cause cardiomyopathy and musculoskeletal disease, but little is known about this atypical kinase. Here we show that ALPK3 is an essential component of the M-band of the sarcomere and define the ALPK3-dependent phosphoproteome. ALPK3 deficiency impaired contractility both in human cardiac organoids and in the hearts of mice harboring a pathogenic truncating Alpk3 variant. ALPK3-dependent phosphopeptides were enriched for sarcomeric components of the M-band and the ubiquitin-binding protein sequestosome-1 (SQSTM1) (also known as p62). Analysis of the ALPK3 interactome confirmed binding to M-band proteins including SQSTM1. In human pluripotent stem cell-derived cardiomyocytes modeling cardiomyopathic ALPK3 mutations, sarcomeric organization and M-band localization of SQSTM1 were abnormal suggesting that this mechanism may underly disease pathogenesis

DOE Project on Heavy Vehicle Aerodynamic Drag FY 2005 Annual Report

Class 8 tractor-trailers consume 11-12% of the total US petroleum use. At high way speeds, 65% of the energy expenditure for a Class 8 truck is in overcoming aerodynamic drag. The project objective is to improve fuel economy of Class 8 tractor-trailers by providing guidance on methods of reducing drag by at least 25%. A 25% reduction in drag would present a 12% improvement in fuel economy at highway speeds, equivalent to about 130 midsize tanker ships per year. Specific goals include: (1) Provide guidance to industry in the reduction of aerodynamic drag of heavy truck vehicles; and (2) Establish a database of experimental, computational, and conceptual design information, and demonstrate the potential of new drag-reduction devices

On the Origin and Trigger of the Notothenioid Adaptive Radiation

Adaptive radiation is usually triggered by ecological opportunity, arising through (i) the colonization of a new habitat by its progenitor; (ii) the extinction of competitors; or (iii) the emergence of an evolutionary key innovation in the ancestral lineage. Support for the key innovation hypothesis is scarce, however, even in textbook examples of adaptive radiation. Antifreeze glycoproteins (AFGPs) have been proposed as putative key innovation for the adaptive radiation of notothenioid fishes in the ice-cold waters of Antarctica. A crucial prerequisite for this assumption is the concurrence of the notothenioid radiation with the onset of Antarctic sea ice conditions. Here, we use a fossil-calibrated multi-marker phylogeny of nothothenioid and related acanthomorph fishes to date AFGP emergence and the notothenioid radiation. All time-constraints are cross-validated to assess their reliability resulting in six powerful calibration points. We find that the notothenioid radiation began near the Oligocene-Miocene transition, which coincides with the increasing presence of Antarctic sea ice. Divergence dates of notothenioids are thus consistent with the key innovation hypothesis of AFGP. Early notothenioid divergences are furthermore congruent with vicariant speciation and the breakup of Gondwana

3D extracellular matrix microenvironment in bioengineered tissue models of primary pediatric and adult brain tumors.

Dynamic alterations in the unique brain extracellular matrix (ECM) are involved in malignant brain tumors. Yet studies of brain ECM roles in tumor cell behavior have been difficult due to lack of access to the human brain. We present a tunable 3D bioengineered brain tissue platform by integrating microenvironmental cues of native brain-derived ECMs and live imaging to systematically evaluate patient-derived brain tumor responses. Using pediatric ependymoma and adult glioblastoma as examples, the 3D brain ECM-containing microenvironment with a balance of cell-cell and cell-matrix interactions supports distinctive phenotypes associated with tumor type-specific and ECM-dependent patterns in the tumor cells\u27 transcriptomic and release profiles. Label-free metabolic imaging of the composite model structure identifies metabolically distinct sub-populations within a tumor type and captures extracellular lipid-containing droplets with potential implications in drug response. The versatile bioengineered 3D tumor tissue system sets the stage for mechanistic studies deciphering microenvironmental role in brain tumor progression

Stable Isotope Evidence for Dietary Overlap between Alien and Native Gastropods in Coastal Lakes of Northern KwaZulu-Natal, South Africa

Tarebia granifera (Lamarck, 1822) is originally from South-East Asia, but has been introduced and become invasive in many tropical and subtropical parts of the world. In South Africa, T. granifera is rapidly invading an increasing number of coastal lakes and estuaries, often reaching very high population densities and dominating shallow water benthic invertebrate assemblages. An assessment of the feeding dynamics of T. granifera has raised questions about potential ecological impacts, specifically in terms of its dietary overlap with native gastropods.A stable isotope mixing model was used together with gut content analysis to estimate the diet of T. granifera and native gastropod populations in three different coastal lakes. Population density, available biomass of food and salinity were measured along transects placed over T. granifera patches. An index of isotopic (stable isotopes) dietary overlap (IDO, %) aided in interpreting interactions between gastropods. The diet of T. granifera was variable, including contributions from microphytobenthos, filamentous algae (Cladophora sp.), detritus and sedimentary organic matter. IDO was significant (>60%) between T. granifera and each of the following gastropods: Haminoea natalensis (Krauss, 1848), Bulinus natalensis (Küster, 1841) and Melanoides tuberculata (Müller, 1774). However, food did not appear to be limiting. Salinity influenced gastropod spatial overlap. Tarebia granifera may only displace native gastropods, such as Assiminea cf. ovata (Krauss, 1848), under salinity conditions below 20. Ecosystem-level impacts are also discussed.The generalist diet of T. granifera may certainly contribute to its successful establishment. However, although competition for resources may take place under certain salinity conditions and if food is limiting, there appear to be other mechanisms at work, through which T. granifera displaces native gastropods. Complementary stable isotope and gut content analysis can provide helpful ecological insights, contributing to monitoring efforts and guiding further invasive species research

Racism as a determinant of health: a systematic review and meta-analysis

Despite a growing body of epidemiological evidence in recent years documenting the health impacts of racism, the cumulative evidence base has yet to be synthesized in a comprehensive meta-analysis focused specifically on racism as a determinant of health. This meta-analysis reviewed the literature focusing on the relationship between reported racism and mental and physical health outcomes. Data from 293 studies reported in 333 articles published between 1983 and 2013, and conducted predominately in the U.S., were analysed using random effects models and mean weighted effect sizes. Racism was associated with poorer mental health (negative mental health: r = -.23, 95% CI [-.24,-.21], k = 227; positive mental health: r = -.13, 95% CI [-.16,-.10], k = 113), including depression, anxiety, psychological stress and various other outcomes. Racism was also associated with poorer general health (r = -.13 (95% CI [-.18,-.09], k = 30), and poorer physical health (r = -.09, 95% CI [-.12,-.06], k = 50). Moderation effects were found for some outcomes with regard to study and exposure characteristics. Effect sizes of racism on mental health were stronger in cross-sectional compared with longitudinal data and in non-representative samples compared with representative samples. Age, sex, birthplace and education level did not moderate the effects of racism on health. Ethnicity significantly moderated the effect of racism on negative mental health and physical health: the association between racism and negative mental health was significantly stronger for Asian American and Latino(a) American participants compared with African American participants, and the association between racism and physical health was significantly stronger for Latino(a) American participants compared with African American participants.<br /