30 research outputs found
The Progressive Increase of Food Waste in America and Its Environmental Impact
Food waste contributes to excess consumption of freshwater and fossil fuels which, along with methane and CO2 emissions from decomposing food, impacts global climate change. Here, we calculate the energy content of nationwide food waste from the difference between the US food supply and the food consumed by the population. The latter was estimated using a validated mathematical model of metabolism relating body weight to the amount of food eaten. We found that US per capita food waste has progressively increased by ∼50% since 1974 reaching more than 1400 kcal per person per day or 150 trillion kcal per year. Food waste now accounts for more than one quarter of the total freshwater consumption and ∼300 million barrels of oil per year
Rapid Plant Identification Using Species- and Group-Specific Primers Targeting Chloroplast DNA
Plant identification is challenging when no morphologically assignable parts are available. There is a lack of broadly applicable methods for identifying plants in this situation, for example when roots grow in mixture and for decayed or semi-digested plant material. These difficulties have also impeded the progress made in ecological disciplines such as soil- and trophic ecology. Here, a PCR-based approach is presented which allows identifying a variety of plant taxa commonly occurring in Central European agricultural land. Based on the trnT-F cpDNA region, PCR assays were developed to identify two plant families (Poaceae and Apiaceae), the genera Trifolium and Plantago, and nine plant species: Achillea millefolium, Fagopyrum esculentum, Lolium perenne, Lupinus angustifolius, Phaseolus coccineus, Sinapis alba, Taraxacum officinale, Triticum aestivum, and Zea mays. These assays allowed identification of plants based on size-specific amplicons ranging from 116 bp to 381 bp. Their specificity and sensitivity was consistently high, enabling the detection of small amounts of plant DNA, for example, in decaying plant material and in the intestine or faeces of herbivores. To increase the efficacy of identifying plant species from large number of samples, specific primers were combined in multiplex PCRs, allowing screening for multiple species within a single reaction. The molecular assays outlined here will be applicable manifold, such as for root- and leaf litter identification, botanical trace evidence, and the analysis of herbivory
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
raw data Wallinger et al MER-12-0242
Molecular detection rates of different Agriotes larvae feeding on different plant species - feeding experiments with fresh plants and decaying tissu
Who wants COVID-19 vaccination to be compulsory? The impact of party cues, left-right ideology, and populism
Vaccine hesitancy is one of the major obstacles for successfully combating the ongoing COVID-19 pandemic. To achieve a sufficiently high vaccination rate, calls for compulsory vaccinations have been discussed controversially. This study analyses what drives citizens’ attitudes towards compulsory vaccination during the COVID-19 pandemic. Specifically, we are interested in the impact of party- and expert cues on public attitudes. We further expect populist attitudes to be an important indicator of the rejection of compulsory vaccination due to their scepticism towards science. To test these expectations, we rely on a cueing experiment conducted on a sample of 2265 German citizens. We test for the effects of in-party and out-party cues as well as public health expert cues. We find evidence for in-party cues, meaning that respondents adjust their position on this issue in the direction of their most preferred party. Similar results can be found for public health expert cues. However, there is no evidence for out-party cues. Further analyses reveal that support for compulsory vaccinations is not affected by left-right placement directly. Instead, only the combination of right-wing attitudes and populism negatively affects support for compulsory vaccination
NMR resonance assignments for the SAM/SAH-binding riboswitch RNA bound to S-adenosylhomocysteine
Riboswitches are structured RNA elements in the 5-untranslated regions of bacterial mRNAs that are able to control the transcription or translation of these mRNAs in response to the specific binding of small molecules such as certain metabolites. Riboswitches that bind with high specificity to either S-adenosylmethionine (SAM) or S-adenosylhomocysteine (SAH) are widespread in bacteria. Based on differences in secondary structure and sequence these riboswitches can be grouped into a number of distinct classes. X-ray structures for riboswitch RNAs in complex with SAM or SAH established a structural basis for understanding ligand recognition and discrimination in many of these riboswitch classes. One class of riboswitchesthe so-called SAM/SAH riboswitch classbinds SAM and SAH with similar affinity. However, this class of riboswitches is structurally not yet characterized and the structural basis for its unusual bispecificity is not established. In order to understand the ligand recognition mode that enables this riboswitch to bind both SAM and SAH with similar affinities, we are currently determining its structure in complex with SAH using NMR spectroscopy. Here, we present the NMR resonance assignment of the SAM/SAH binding riboswitch (env9b) in complex with SAH as a prerequisite for a solution NMR-based high-resolution structure determination
The structure of the SAM/SAH-binding riboswitch
S-adenosylmethionine (SAM) is a central metabolite since it is used as a methyl group donor in many different biochemical reactions. Many bacteria control intracellular SAM concentrations using riboswitch-based mechanisms. A number of structurally different riboswitch families specifically bind to SAM and mainly regulate the transcription or the translation of SAM-biosynthetic enzymes. In addition, a highly specific riboswitch class recognizes S-adenosylhomocysteine (SAH)the product of SAM-dependent methyl group transfer reactionsand regulates enzymes responsible for SAH hydrolysis. High-resolution structures are available for many of these riboswitch classes and illustrate how they discriminate between the two structurally similar ligands SAM and SAH. The so-called SAM/SAH riboswitch class binds both ligands with similar affinities and is structurally not yet characterized. Here, we present a high-resolution nuclear magnetic resonance structure of a member of the SAM/SAH-riboswitch class in complex with SAH. Ligand binding induces pseudoknot formation and sequestration of the ribosome binding site. Thus, the SAM/SAH-riboswitches are translational OFF'-switches. Our results establish a structural basis for the unusual bispecificity of this riboswitch class. In conjunction with genomic data our structure suggests that the SAM/SAH-riboswitches might be an evolutionary late invention and not a remnant of a primordial RNA-world as suggested for other riboswitches