197 research outputs found

    Forest structure, diversity, and primary production in relation to disturbance severity

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    Differential disturbance severity effects on forest vegetation structure, species diversity, and net primary production (NPP) have been long theorized and observed. Here, we examined these factors concurrently to explore the potential for a mechanistic pathway linking disturbance severity, changes in light environment, leaf functional response, and wood NPP in a temperate hardwood forest.Using a suite of measurements spanning an experimental gradient of tree mortality, we evaluated the direction and magnitude of change in vegetation structural and diversity indexes in relation to wood NPP. Informed by prior observations, we hypothesized that forest structural and species diversity changes and wood NPP would exhibit either a linear, unimodal, or threshold response in relation to disturbance severity. We expected increasing disturbance severity would progressively shift subcanopy light availability and leaf traits, thereby coupling structural and species diversity changes with primary production.Linear or unimodal changes in three of four vegetation structural indexes were observed across the gradient in disturbance severity. However, disturbance‐related changes in vegetation structure were not consistently correlated with shifts in light environment, leaf traits, and wood NPP. Species diversity indexes did not change in response to rising disturbance severity.We conclude that, in our study system, the sensitivity of wood NPP to rising disturbance severity is generally tied to changing vegetation structure but not species diversity. Changes in vegetation structure are inconsistently coupled with light environment and leaf traits, resulting in mixed support for our hypothesized cascade linking disturbance severity to wood NPP.We examined multiple metrics of vegetation structural and biological diversity concurrently to explore the potential for a mechanistic pathway linking disturbance severity, changes in light environment, leaf functional response, and wood NPP in a temperate hardwood forest. Significant linear or unimodal changes in three of four vegetation structural indexes were observed across the gradient in disturbance severity, although disturbance‐related changes in vegetation structure were not consistently correlated with shifts in light environment, leaf traits, and wood NPP. We conclude that, in our study system, the sensitivity of wood NPP to rising disturbance severity is generally tied to changing vegetation structure but not species diversity.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155474/1/ece36209.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155474/2/ece36209_am.pd

    Comparative immunogenicity and efficacy studies with oral rabies virus vaccine SAD P5/88 in raccoon dogs and red foxes

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    A comparative study of immunogenicity and efficacy of the oral rabies virus vaccine SAD P5/88 in raccoon dogs and foxes was conducted. The raccoon dogs received 10 (n = 6), 106.3 (n = 6) or 105.7 FFU SAD P5/88 (n = 5) by direct oral application, and subsequently all animals seroconverted. The foxes received 107.2 (n = 4), 106.2 (n = 4), 105.2 (n = 4) and 104.2 FFU SAD P5/88 (n = 5) by the same route. On days 106 and 196 post vaccination 10 raccoon dogs and 16 foxes were challenged with a relevant street virus, respectively. All 10 raccoon dogs vaccinated with 106.3 (n = 5) or 105.7 FFU SAD P5/88 (n = 5) survived the challenge, whereas all control animals (n = 5) died of rabies. Two foxes vaccinated with 104.2 FFU and one fox vaccinated with 105.2 FFU died of rabies on day 7, 17 and 12 post infection, respectively. Also all control foxes succumbed to rabies. Our findings demonstrate that SAD P5/88 is not only an effective vaccine for oral vaccination of foxes but also for that of raccoon dogs

    Evidenz und Tradition am Beispiel der Phytopharmaka

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    Summary Herbal medicinal products - Evidence and tradition from a historical perspective Background: Aside from the fully licensed herbal medicines there are products on the European pharmaceutical market which are registered by virtue of their longstanding traditional use. The normal registration procedure does not apply to them because presently they do not meet the legal requirements for a full license as set out in the relevant European Union Directive. One of these requirements, proof of tradition, has so far been dealt with in different ways and fails to meet the criteria of good practice. Method: This analysis is based on a selective literature search in PubMed and in databases of medical and pharmaceutical history, interviews with licensing experts, a consensus meeting attended by researchers with a background in general medicine, phytotherapy, medical and pharmaceutical history, biometry, ethnopharmacology, pharmacognosy and the pharmaceutical industry. Results and discussion: The 2004 EU Directive, which governs the registration of Traditional Herbal Medicinal Products and demands proof of tradition, is a regulatory construct and, above all, the outcome of a political process that has ended in a pragmatic compromise. The concept of tradition applied in the Directive does not sufficiently reflect the semantic breadth of the term. The only condition defined is that a specific commercial preparation needs to have been on the market for 30 years (15 of them inside the EU). Such an approach does not make full scientific use of the evidence available because the information excerpted from historical sources, if adequately processed, may yield valuable insights. This applies to indications, modes of application, efficacy and product safety (innocuousness). Such criteria should enter in full into the benefit-risk-analysis of applied preparations, in the registration process as well as in the therapeutic practice. Conclusion: When registering Traditional Herbal Medicinal Products the criterion of evidence-based medicine will only be met if all the facts available are assessed and evaluated, over and above the formally stipulated regulatory provisions (30 years, product reference). To this end, the scientific methods (from among the natural, life or cultural sciences), which are recognized as authoritative in each case, must be applied

    Discovery of the Lanthipeptide Curvocidin and Structural Insights into its Trifunctional Synthetase CuvL

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    Lanthipeptides are ribosomally-synthesized natural products from bacteria featuring stable thioether-crosslinks and various bioactivities. Herein, we report on a new clade of tricyclic class-IV lanthipeptides with curvocidin from Thermomonospora curvata as its first representative. We obtained crystal structures of the corresponding lanthipeptide synthetase CuvL that showed a circular arrangement of its kinase, lyase and cyclase domains, forming a central reaction chamber for the iterative substrate processing involving nine catalytic steps. The combination of experimental data and artificial intelligence-based structural models identified the N-terminal subdomain of the kinase domain as the primary site of substrate recruitment. The ribosomal precursor peptide of curvocidin employs an amphipathic α-helix in its leader region as an anchor to CuvL, while its substrate core shuttles within the central reaction chamber. Our study thus reveals general principles of domain organization and substrate recruitment of class-IV and class-III lanthipeptide synthetases.Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659Research Training Group RTG 2473 "Bioactive Peptides"RTG 2473 "Bioactive Peptides"Peer Reviewe

    An Ancient Relation between Units of Length and Volume Based on a Sphere

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    The modern metric system defines units of volume based on the cube. We propose that the ancient Egyptian system of measuring capacity employed a similar concept, but used the sphere instead. When considered in ancient Egyptian units, the volume of a sphere, whose circumference is one royal cubit, equals half a hekat. Using the measurements of large sets of ancient containers as a database, the article demonstrates that this formula was characteristic of Egyptian and Egyptian-related pottery vessels but not of the ceramics of Mesopotamia, which had a different system of measuring length and volume units

    A proposed architecture and method of operation for improving the protection of privacy and confidentiality in disease registers

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    BACKGROUND: Disease registers aim to collect information about all instances of a disease or condition in a defined population of individuals. Traditionally methods of operating disease registers have required that notifications of cases be identified by unique identifiers such as social security number or national identification number, or by ensembles of non-unique identifying data items, such as name, sex and date of birth. However, growing concern over the privacy and confidentiality aspects of disease registers may hinder their future operation. Technical solutions to these legitimate concerns are needed. DISCUSSION: An alternative method of operation is proposed which involves splitting the personal identifiers from the medical details at the source of notification, and separately encrypting each part using asymmetrical (public key) cryptographic methods. The identifying information is sent to a single Population Register, and the medical details to the relevant disease register. The Population Register uses probabilistic record linkage to assign a unique personal identification (UPI) number to each person notified to it, although not necessarily everyone in the entire population. This UPI is shared only with a single trusted third party whose sole function is to translate between this UPI and separate series of personal identification numbers which are specific to each disease register. SUMMARY: The system proposed would significantly improve the protection of privacy and confidentiality, while still allowing the efficient linkage of records between disease registers, under the control and supervision of the trusted third party and independent ethics committees. The proposed architecture could accommodate genetic databases and tissue banks as well as a wide range of other health and social data collections. It is important that proposals such as this are subject to widespread scrutiny by information security experts, researchers and interested members of the general public, alike

    Forest Biodiversity Assessment in Peruvian Andean Montane Cloud Forest

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    Cloud forests are unusual and fragile habitats, being one of the least studied and least understood ecosystems. The tropical Andean dominion is considered one of the most significant places in the world as rega rds biological diversity, with a very high level of endemism. The biodiversity was analysed in an isolated remnant area of a tropical montane cloud forest known as the ?Bosque de Neblina de Cuyas?, in the North of the Peruvian Andean range. Composition, structure and dead wood were measured or estimated. The values obtained were compared with other cloud forests. The study revealed a high level of forest biodiversity, although the level of biodiversity differs from one area to another: in the inner areas, where human pressure is almost inexistent, the biodiversity values increase. The high species richness and the low dominance among species bear testimony to this montane cloud forest as a real enclave of biodiversity

    Precision restoration: a necessary approach to foster forest recovery in the 21st century

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    We thank S. Tabik, E. Guirado, and Garnata Drone SL for fruitful debates about the application of remote sensing and artificial intelligence in restoration. E. McKeown looked over the English version of the manuscript. Original drawings were made by J. D. Guerrero. This work was supported by projects RESISTE (P18-RT-1927) from the Consejeria de Economia, Conocimiento, y Universidad from the Junta de Andalucia, and AVA201601.19 (NUTERA-DE I), DETECTOR (A-RNM-256-UGR18), and AVA2019.004 (NUTERA-DE II), cofinanced (80%) by the FEDER Program. F.M.-R. acknowledges the support of the Agreement 4580 between OTRI-UGR and the city council of La Zubia. We thank an anonymous reviewer for helpful comments that improved the manuscript.Forest restoration is currently a primary objective in environmental management policies at a global scale, to the extent that impressive initiatives and commitments have been launched to plant billions of trees. However, resources are limited and the success of any restoration effort should be maximized. Thus, restoration programs should seek to guarantee that what is planted today will become an adult tree in the future, a simple fact that, however, usually receives little attention. Here, we advocate for the need to focus restoration efforts on an individual plant level to increase establishment success while reducing negative side effects by using an approach that we term “precision forest restoration” (PFR). The objective of PFR will be to ensure that planted seedlings or sowed seeds will become adult trees with the appropriate landscape configuration to create functional and self-regulating forest ecosystems while reducing the negative impacts of traditional massive reforestation actions. PFR can take advantage of ecological knowledge together with technologies and methodologies from the landscape scale to the individual- plant scale, and from the more traditional, low-tech approaches to the latest high-tech ones. PFR may be more expensive at the level of individual plants, but will be more cost-effective in the long term if it allows for the creation of resilient forests able to providemultiple ecosystemservices. PFR was not feasible a few years ago due to the high cost and low precision of the available technologies, but it is currently an alternative that might reformulate a wide spectrum of ecosystem restoration activities.Junta de Andalucia P18-RT-1927European Commission AVA201601.19 A-RNM-256-UGR18 AVA2019.004OTRI-UGR 4580city council of La Zubia 458

    Phylogenetic and functional marker genes to study ammonia-oxidizing microorganisms (AOM) in the environment

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    The oxidation of ammonia plays a significant role in the transformation of fixed nitrogen in the global nitrogen cycle. Autotrophic ammonia oxidation is known in three groups of microorganisms. Aerobic ammonia-oxidizing bacteria and archaea convert ammonia into nitrite during nitrification. Anaerobic ammonia-oxidizing bacteria (anammox) oxidize ammonia using nitrite as electron acceptor and producing atmospheric dinitrogen. The isolation and cultivation of all three groups in the laboratory are quite problematic due to their slow growth rates, poor growth yields, unpredictable lag phases, and sensitivity to certain organic compounds. Culture-independent approaches have contributed importantly to our understanding of the diversity and distribution of these microorganisms in the environment. In this review, we present an overview of approaches that have been used for the molecular study of ammonia oxidizers and discuss their application in different environments

    The role of open abdomen in non-trauma patient : WSES Consensus Paper

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    The open abdomen (OA) is defined as intentional decision to leave the fascial edges of the abdomen un-approximated after laparotomy (laparostomy). The abdominal contents are potentially exposed and therefore must be protected with a temporary coverage, which is referred to as temporal abdominal closure (TAC). OA use remains widely debated with many specific details deserving detailed assessment and clarification. To date, in patients with intra-abdominal emergencies, the OA has not been formally endorsed for routine utilization; although, utilization is seemingly increasing. Therefore, the World Society of Emergency Surgery (WSES), Abdominal Compartment Society (WSACS) and the Donegal Research Academy united a worldwide group of experts in an international consensus conference to review and thereafter propose the basis for evidence-directed utilization of OA management in non-trauma emergency surgery and critically ill patients. In addition to utilization recommendations, questions with insufficient evidence urgently requiring future study were identified.Peer reviewe
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