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Abstract Background PacBio HiFi sequencing provides highly accurate long-read sequencing datasets which are of great advantage for whole genome sequencing projects. One limitation of the method is the requirement for high quality, high molecular weight input DNA. This can be particularly challenging for plants that frequently contain common and species-specific secondary metabolites, which often interfere with downstream processes. Cape Primroses (genus Streptocarpus), are some of these recalcitrant plants and are selected here as material to develop a high quality, high molecular weight DNA extraction protocol for long read genome sequencing. Results We developed a DNA extraction method for PacBio HiFi sequencing for Streptocarpus grandis and Streptocarpus kentaniensis. A CTAB lysis buffer was employed to avoid guanidine, and the traditional chloroform and phenol purification steps were replaced with pre-lysis sample washes. Best cells/nucleus lysis was achieved with 4 h at 58 °C. The obtained high quality and high molecular weight DNAs were tested in PacBio SMRTBell™ library preparations, which resulted in circular consensus sequencing (CCS) reads from 17 to 27 Gb per cell, and a read length N50 from 14 to 17 kbp. To evaluate the quality of the reads for whole genome sequencing, they were assembled with HiFiasm into draft genomes, with N50 = 49 Mb and 23 Mb, and L50 = 10 and 11. The longest contigs were 95 Mb and 57 Mb respectively, showing good contiguity as these are longer than the theoretical chromosome length (genome size/chromosome number) of 78 Mb and 55 Mb, for S. grandis and S. kentaniensis respectively. Conclusions DNA extraction is a critical step towards obtaining a complete genome assembly. Our DNA extraction method here provided the required high quality, high molecular weight DNA for successful standard-input PacBio HiFi library preparation. The contigs from those reads showed a high contiguity, providing a good starting draft assembly towards obtaining a complete genome. The results obtained here were highly promising, and demonstrated that the DNA extraction method developed here is compatible with PacBio HiFi sequencing and suitable for de novo whole genome sequencing projects of plants.

Abstract Plant molecular identification studies have, until recently, been limited to the use of highly conserved markers from plastid and other organellar genomes, compromising resolution in highly diverse plant clades. Due to their higher evolutionary rates and reduced paralogy, low-copy nuclear genes overcome this limitation but are difficult to sequence with conventional methods and require high-quality input DNA. Aloe vera and its relatives in the Alooideae clade (Asphodelaceae, subfamily Asphodeloideae) are of economic interest for food and health products and have horticultural value. However, pressing conservation issues are increasing the need for a molecular identification tool to regulate the trade. With > 600 species and an origin of ± 15 million years ago, this predominantly African succulent plant clade is a diverse and taxonomically complex group for which low-copy nuclear genes would be desirable for accurate species discrimination. Unfortunately, with an average genome size of 16.76 pg, obtaining high coverage sequencing data for these genes would be prohibitively costly and computationally demanding. We used newly generated transcriptome data to design a customised RNA-bait panel targeting 189 low-copy nuclear genes in Alooideae. We demonstrate its efficacy in obtaining high-coverage sequence data for the target loci on Illumina sequencing platforms, including degraded DNA samples from museum specimens, with considerably improved phylogenetic resolution. This customised target capture sequencing protocol has the potential to confidently indicate phylogenetic relationships of Aloe vera and related species, as well as aid molecular identification applications.

Tulsi (Holy basil, Ocimum tenuiflorum L., Lamiaceae), native to Asia, has become globalised as the cultural, cosmetic, and medicinal uses of the herb have been popularised. DNA barcoding, a molecular technique used to identify species based on short regions of DNA, can discriminate between different species and identify contaminants and adulterants. This study aimed to explore the values associated with Tulsi in the United Kingdom (UK) and authenticate samples using DNA barcoding. A mixed methods approach was used, incorporating social research (i.e., structured interviews) and DNA barcoding of Ocimum samples using the ITS and trnH-psbA barcode regions. Interviews revealed the cultural significance of Tulsi: including origins, knowledge exchange, religious connotations, and medicinal uses. With migration, sharing of plants and seeds has been seen as Tulsi plants are widely grown in South Asian (SA) households across the UK. Vouchered Ocimum specimens (n = 33) were obtained to create reference DNA barcodes which were not available in databases. A potential species substitution of O. gratissimum instead of O. tenuiflorum amongst SA participants was uncovered. Commercial samples (n = 47) were difficult to authenticate, potentially due to DNA degradation during manufacturing processes. This study highlights the cultural significance of Tulsi, despite a potential species substitution, the plant holds a prestigious place amongst SA families in the UK. DNA barcoding was a reliable way to authenticate Ocimum species.

Infections with COVID-19 can induce thrombophilia and increase the risk of thrombotic events. We describe a case of a 64- years-old male who presents with intermediate-risk pulmonary embolism and brachial artery thrombosis secondary to an undiagnosed patent foramen ovale and COVID-19 infection. The patient was successfully treated with thrombolysis and heparin infusions and was discharged home with long-term anticoagulation. Managing patients with multiple pathologies occurring concurrently requires effective inter-speciality working in order to take a holistic approach to managing the patient opposed to managing the conditions in isolation. This case report highlights how clinical guidelines can support decision making of the individual pathologies but working as a team will enable the best care.

The potential value of DNA barcoding for the identification of medicinal plants and authentication of traded plant materials has been widely recognized; however, a number of challenges remain before DNA methods are fully accepted as an essential quality control method by industry and regulatory authorities. The successes and limitations of conventional DNA barcoding are considered in relation to important members of the Lamiaceae. The mint family (Lamiaceae) contains over one thousand species recorded as having a medicinal use, with many more exploited in food and cosmetics for their aromatic properties. The family is characterized by a diversity of secondary products, most notably the essential oils (EOs) produced in external glandular structures on the aerial parts of the plant that typify well-known plants of the basil (Ocimum), lavender (Lavandula), mint (Mentha), thyme (Thymus), sage (Salvia) and related genera. This complex, species-rich family includes widely cultivated commercial hybrids and endangered wild-harvested traditional medicines, and examples of potential toxic adulterants within the family are explored in detail. The opportunities provided by next generation sequencing technologies to whole plastome barcoding and nuclear genome sequencing are also discussed with relevant examples.

DNA barcoding of herbal medicines has been mainly concerned with authentication of products in trade and has raised awareness of species substitution and adulteration. More recently DNA barcodes have been included in pharmacopoeias, providing tools for regulatory purposes. The commonly used DNA barcoding regions in plants often fail to resolve identification to species level. This can be especially challenging in evolutionarily complex groups where incipient or reticulate speciation is ongoing. In this study, we take a phylogenomic approach, analyzing whole plastid sequences from the evolutionarily complex genus Berberis in order to develop DNA barcodes for the medicinally important species Berberis aristata. The phylogeny reconstructed from an alignment of ∼160 kbp of chloroplast DNA for 57 species reveals that the pharmacopoeial species in question is polyphyletic, complicating development of a species-specific DNA barcode. Instead we propose a DNA barcode that is clade specific, using our phylogeny to define Operational Phylogenetic Units (OPUs). The plastid alignment is then reduced to small, informative DNA regions including nucleotides diagnostic for these OPUs. These DNA barcodes were tested on commercial samples, and shown to discriminate plants in trade and therefore to meet the requirement of a pharmacopoeial standard. The proposed method provides an innovative approach for inferring DNA barcodes for evolutionarily complex groups for regulatory purposes and quality control.

DNA barcoding is a widely accepted technique for the identification of plant materials, and its application to the authentication of commercial medicinal plants has attracted significant attention. The incorporation of DNA-based technologies into the quality testing protocols of international pharmacopoeias represents a step-change in status, requiring the establishment of standardized, reliable and reproducible methods. The process by which this can be achieved for any herbal medicine is described, using Hypericum perforatum L. (St John’s Wort) and potential adulterant Hypericum species as a case study. A range of practical issues are considered including quality control of DNA sequences from public repositories and the construction of individual curated databases, choice of DNA barcode region(s) and the identification of informative polymorphic nucleotide sequences. A decision tree informs the structure of the manuscript and provides a template to guide the development of future DNA barcode tests for herbals.

Using the Indian medicinal plant Tulsi (Holy Basil) as a case study, we have tested to what extent the discrepancy between vernacular and scientific nomenclature can be resolved, whether the presumed chemical diversity underlying the medicinal use of Tulsi has a genetic component, and whether it is possible to detect this genetic component using genetic barcoding markers. Based on four plastidic markers, we can define several haplotypes within Ocimum that are consistent across these markers. Haplotype II is congruent with O. tenuiflorum, while haplotype I extends over several members of the genus and cannot be resolved into genetically separate subclades. The vernacular subdivision of Tulsi into three types (Rama, Krishna, Vana) can only be partially linked with genetic differences-whereby Rama and Krishna Tulsi can be assigned to O. tenuiflorum, while Vana Tulsi belongs to haplotype I. This genetic difference is mirrored by differences in the profiles of secondary compounds. While developmental state and light quality modulate the amplitude to which the chemical profile is expressed, the profile itself seems to be linked with genetic differences. We finally develop an authentication assay that makes use of a characteristic single nucleotide polymorphism in one of the barcoding markers, establishing a differential restriction pattern that can be used to discriminate Vana Tulsi.

Artiklen undersøger de studerendes forventninger til undervisere og undervisning gennem et survey af ca. 200 grunduddannelses- og overbygnings­­studerende og finder, at der er stærkere præferencer for underviserens forelæsning og gennemgang af pensum i forhold til mere inddragende og perspektiverende undervisning. Ligeledes undersøges demografiske, strukturelle samt subjektive karakteristikas evne til at forklare variationer i de studerendes præferencer. Mod forventning finder vi, at de studerendes præferencer til underviser og undervisning kun i meget ringe grad kan forklares ved de undersøgte faktorer. The paper examines students' expectations regarding teachers and teaching through a survey of approximately 200 BA and MA students. The findings suggest that students generally prefer lectures and presentations of the curriculum given by teachers rather than alternative methods of curriculum delivery. Demographic, structural and subjective characteristics of the students are included in models to explain variations in student preferences. Contra to our expectations, we find that the preferences of the students regarding teachers and teaching methods are only to a very limited extent explained by the included variables.

There is considerable potential for the use of DNA barcoding methods to authenticate raw medicinal plant materials, but their application to testing commercial products has been controversial. A simple PCR test targeting species-specific sequences within the nuclear ribosomal internal transcribed spacer (ITS) region was adapted to screen commercial products for the presence of Hypericum perforatum L. material. DNA differing widely in amount and extent of fragmentation was detected in a number of product types. Two assays were designed to further analyse this DNA using a curated database of selected Hypericum ITS sequences: A qPCR assay based on a species-specific primer pair spanning the ITS1 and ITS2 regions, using synthetic DNA reference standards for DNA quantitation and a Next Generation Sequencing (NGS) assay separately targeting the ITS1 and ITS2 regions. The ability of the assays to detect H. perforatum DNA sequences in processed medicines was investigated. Out of twenty different matrices tested, both assays detected H. perforatum DNA in five samples with more than 103 ITS copies µL−1 DNA extract, whilst the qPCR assay was also able to detect lower levels of DNA in two further samples. The NGS assay confirmed that H. perforatum was the major species in all five positive samples, though trace contaminants were also detected.

The large number of displaced Afghans represents both a protection and an urban development challenge for the government and international community.

Street-level workers are notoriously difficult to manage. Over the years, scholars have highlighted the importance of social dynamics and informal and collective leadership in street-level contexts. Yet, the question of how formal managers can support street-level workers' performance and well-being remains underexplored. Building on insights from the street-level and generic leadership literatures, the authors seek to delineate a role for formal managers that takes seriously the particularities of the street-level context. The authors develop a concept of street-level leadership that is underpinned by a relational approach and focused on activating street-level workers' professional knowledge and building supportive communities, with the purpose of supporting professional uses of discretion, conscientious prioritizations, and the ability to handle moral dilemmas and emotional strain. Empirical examples illustrate street-level leadership in practice. Future research should explore the proposed mechanisms and effects of street-level leadership, including important HRM outcomes such as job satisfaction, retention, and burnout. [ABSTRACT FROM AUTHOR]

Research shows that leadership identity is important for public managers' behavior, but has until now relied primarily on self-reports. Arguing that leadership identity is a relational concept, this article compares the managers' experienced leadership identity with the corresponding follower perceived leadership identity and followers' role perceptions of their leaders. Further, we test whether leadership training affects these concepts. Panel data from 911 municipal employees and their 84 managers confirms that managers experience that they have a more dominant leadership identity relative to their employees' perception, but that employees see their managers as having a more dominant leadership identity after the managers' participation in leadership training. Data from 171 managers and their 1,572 employees in another municipality further show that many employees emphasize the professional role of their manager. Our study implies that public managers should consider prioritizing leadership training to strengthen their followers' perceptions of them as leaders. [ABSTRACT FROM AUTHOR]

Although researchers have discussed autonomy as important at the organizational level, the autonomy of the individual manager has not received similar attention. Knowledge about how managerial autonomy is used is, however, important for understanding the conditions under which management matters. We ask whether perceived managerial autonomy enables public managers to prioritize their efforts to support their individual career progression, organizational goal attainment, or both. Based on survey-data from 854 Danish public managers, we find perceived managerial autonomy is positively related to managers ability of aligning their time efforts towards as well their own career progression as towards obtaining organizational goals. [ABSTRACT FROM AUTHOR]

This article argues for the inclusion of regulations in studies of EU policy implementation and compliance. Although both EU directives and EU regulations are to be implemented by the member states, the literature has devoted almost exclusive attention to directives. This is because, first, directives are considered more important than regulations. Second, the notification of the transposition of directives provides a convenient way to compare implementation records. Third, the transposition of directives allegedly introduces an extra implementation step. However, upon closer inspection all three reasons are flawed. Regulations – like directives – often require national rules to enter into effect, a fact long accepted by the European Court of Justice. This creates a situation remarkably similar to the transposition of directives. By analysing two case studies, we contribute by detailing this politico-legal situation, demonstrating its empirical relevance and sketching a new research agenda on the supplementation of EU regulations with national rules. [ABSTRACT FROM AUTHOR]