One-step synthesis and XPS investigations of chiral NHC–Au(0)/Au(i) nanoparticles

Although N-heterocyclic carbenes (NHCs) have been demonstrated as suitable ligands for the stabilisation of gold nanoparticles (AuNPs) through a variety of methods, the manner in which such AuNPs form is yet to be fully elucidated. We report a simple and fast one-step synthesis of uniform chiral (L/D)-histidin-2-ylidene stabilised gold nanoparticles using the organometallic Au(I) complex as a well defined starting material. The resulting nanoparticles have an average size of 2.35 ± 0.43 nm for the L analog whereas an average size of 2.25 ± 0.39 nm was found for the D analog. X-ray photoelectron spectroscopy analyses reveal the presence of Au(I) and Au(0) in all NHC stabilised AuNPs. In contrast, measured X-ray photoelectron spectra of dodecanethiol protected gold nanoparticles showed only the presence of a Au(0) species. This observation leads us to postulate that AuNPs synthesised from organometallic NHC–Au(I) complexes exhibit a monolayer of Au(I) surrounding a Au(0) core. This work highlights the importance of synthetic method choice for NHC-stabilized AuNPs, as this could determine Au oxidation states and resulting AuNP properties such as catalytic activities and stabilities

Cross-Resistance of the Codling Moth against Different Isolates of Cydia pomonella Granulovirus Is Caused by Two Different but Genetically Linked Resistance Mechanisms

Cydia pomonella granulovirus (CpGV) is a widely used biological control agent of the codling moth. Recently, however, the codling moth has developed different types of field resistance against CpGV isolates. Whereas type I resistance is Z chromosomal inherited and targeted at the viral gene pe38 of isolate CpGV-M, type II resistance is autosomal inherited and targeted against isolates CpGV-M and CpGV-S. Here, we report that mixtures of CpGV-M and CpGV-S fail to break type II resistance and is expressed at all larval stages. Budded virus (BV) injection experiments circumventing initial midgut infection provided evidence that resistance against CpGV-S is midgut-related, though fluorescence dequenching assay using rhodamine-18 labeled occlusion derived viruses (ODV) could not fully elucidate whether the receptor binding or an intracellular midgut factor is involved. From our peroral and intra-hemocoel infection experiments, we conclude that two different (but genetically linked) resistance mechanisms are responsible for type II resistance in the codling moth: resistance against CpGV-M is systemic whereas a second and/or additional resistance mechanism against CpGV-S is located in the midgut of CpR5M larvae

Suicide risk after psychiatric discharge: study protocol of a naturalistic, long-term, prospective observational study

Background!#!Suicide risk of psychiatric patients has proven to be strongly increased in the months after discharge from a psychiatric hospital. Despite this high risk, there is a lack of systematic research on the causes of this elevated suicide risk as well as a lack of treatment and intervention for patients at high risk after discharge. The main objective of this pilot study is, firstly, to examine the factors contributing to the elevated !##!Methods!#!In this multi-centre pilot study, treatment as usual is complemented by an additional 18-month post-discharge setting of care for psychiatric patients at high risk for suicide. Two groups of patients differing in the amount of post-discharge personal contacts will be compared. One group of patients will be offered continuous personal contacts after discharge (months 1-6: monthly contacts; months 6-18: every 2 months) while another group of patients will receive contacts only at months 6, 12, and 18 after discharge. Data on suicidality, as well as associated with other symptoms, treatment, and significant events, will be collected. In the case of health-related severe events, the setting of care allows the patient to have the opportunity to connect with the doctor or therapist treating the patient.!##!Discussion!#!The results of this study will contribute to identifying critical factors raising suicide risk after discharge and will demonstrate the potential influence on suicide prevention of a setting of care with regular personal contact after discharge.!##!Trial registration!#!ZMVI1-2517FSB135 - funded by the German Federal Ministry of Health

Using Next Generation Sequencing to Identify and Quantify the Genetic Composition of Resistance-Breaking Commercial Isolates of Cydia pomonella Granulovirus

The use of Cydia pomonella granulovirus (CpGV) isolates as biological control agents of codling moth (CM) larvae is important in organic and integrated pome fruit production worldwide. The commercially available isolates CpGV-0006, CpGV-R5, and CpGV-V15 have been selected for the control of CpGV resistant CM populations in Europe. In infection experiments, CpGV-0006 and CpGV-R5 were able to break type I resistance and to a lower extent also type III resistance, whereas CpGV-V15 overcame type I and the rarely occurring type II and type III resistance. The genetic background of the three isolates was investigated with next generation sequencing (NGS) tools by comparing their nucleotide compositions to whole genome alignments of five CpGV isolates representing the known genetic diversity of the CpGV genome groups A to E. Based on the distribution of single nucleotide polymorphisms (SNPs) in Illumina sequencing reads, we found that the two isolates CpGV-0006 and CpGV-R5 have highly similar genome group compositions, consisting of about two thirds of the CpGV genome group E and one third of genome group A. In contrast, CpGV-V15 is composed of equal parts of CpGV genome group B and E. According to the identified genetic composition of these isolates, their efficacy towards different resistance types can be explained and predictions on the success of resistance management strategies in resistant CM populations can be made