Bostonia. Volume 16

Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs

assessment of pd 1 pd l1 colocalization in hepatocellular carcinoma hcc using bright field double labeling and quantitative digital image analysis

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Narrative Medizin – was ist es, was bringt es, wie setzt man es um?

Erzählungen spielten schon immer eine wichtige Rolle in der Medizin. Mit Beginn der "modernen" Medizin wurden diese Erzählungen mehr und mehr vernachlässigt, der Fokus lag auf "Fakten", die als objektiv und wissenschaftlich galten. In den letzten Jahren jedoch erleben Erzählungen eine Renaissance – insbesondere Patientenerzählungen und Geschichten über das, was zwischen Ärzten und Patienten geschieht. Dies resultierte in der Formulierung von Narrativer Medizin oder Narrative based Medicine (NbM). Der Begriff wurde insbesondere in Abgrenzung zur evidenzbasierten Medizin (EbM) entwickelt. Man wollte damit auch auf die Grenzen der EbM hinweisen. Was aber wird unter Narrativer Medizin verstanden? Die Spannbreite geht von einer besonderen therapeutischen Methode, einer spezifischen Art der Arzt-Patienten- Kommunikation bis hin zu einer qualitativen Forschungsmethode. Was sind die Potentiale von NbM und was bedeuten sie für Theorie, Forschung und Anwendung in der hausärztlichen Medizin? Wo liegen ihre Begrenzungen für die hausärztliche Medizin?Narratives have always been a vital part of medicine. With the rise of "modern" medicine narratives have been more and more neglected in favour of "facts and findings" regarded as more objective and scientific. Yet, in the recent years there is a renaissance of narratives – especially patient narratives and the unfolding story between doctors and patients. Eventually this led to the formation of so called Narrative based Medicine (NbM). The term was coined specifically in distinction to Evidence based Medicine (EbM), with NbM being propagated to counteract the shortcomings of EbM. But what does narrative medicine actually contain? Its’ meaning spans from a specific therapeutic tool, a special form of doctor-patient-communication to a qualitative research tool. What are the potentials of NbM and its implications for theory, research, as well as for general practice? Where are the limitations of a narrative approach in general practice

Octane isomer dynamics in H-ZSM-5 as a function of Si/Al ratio:a quasi-elastic neutron scattering study

Dynamical behaviour of n-octane and 2,5-dimethylhexane in H-ZSM-5 zeolite catalysts of differing Si/Al ratios (15 and 140) was probed using quasi-elastic neutron scattering, to understand molecular shape and Brønsted acid site density effects on the behaviour of common species in the fluid catalytic cracking (FCC) process, where H-ZSM-5 is an additive catalyst. Between 300 and 400 K, n-octane displayed uniaxial rotation around its long axis. However, the population of mobile molecules was larger in H-ZSM-5(140), suggesting that the lower acid site concentration allows for more molecules to undergo rotation. The rotational diffusion coefficients were higher in H-ZSM-5(140), reflecting this increase in freedom. 2,5-dimethylhexane showed qualitative differences in behaviour to n-octane, with no full molecule rotation, probably due to steric hindrance in the constrictive channels. However, methyl group rotation in the static 2,5-dimethylhexane molecules was observed, with lower mobile fractions in H-ZSM-5(15), suggesting that this rotation is less hindered when fewer Brønsted sites are present. This was further illustrated by the lower activation barrier calculated for methyl rotation in H-ZSM-5(140). We highlight the significant immobilizing effect of isomeric branching in this important industrial catalyst and show how compositional changes of the zeolite can affect a range of dynamical behaviours of common FCC species upon adsorption

Liquid Chromatography Electron Capture Dissociation Tandem Mass Spectrometry (LC-ECD-MS/MS) versus Liquid Chromatography Collision-induced Dissociation Tandem Mass Spectrometry (LC-CID-MS/MS) for the Identification of Proteins

Electron capture dissociation (ECD) offers many advantages over the more traditional fragmentation techniques for the analysis of peptides and proteins, although the question remains: How suitable is ECD for incorporation within proteomic strategies for the identification of proteins? Here, we compare LC-ECD-MS/MS and LC-CID-MS/MS as techniques for the identification of proteins.Experiments were performed on a hybrid linear ion trap–Fourier transform ion cyclotron resonance mass spectrometer. Replicate analyses of a six-protein (bovine serum albumin, apo-transferrin,lysozyme, cytochrome c, alcohol dehydrogenase, and β-galactosidase) tryptic digest were performed and the results analyzed on the basis of overall protein sequence coverage and sequence tag lengths within individual peptides. The results show that although protein coverage was lower for LC-ECDMS/MS than for LC-CID-MS/MS, LC-ECD-MS/MS resulted in longer peptide sequence tags,providing greater confidence in protein assignment

Improving photocatalytic energy conversion via NAD(P)H

NAD(P)H behaves as an energy/chemical “currency,” carrying hydrogen in a biologically convertible form and donates electrons in numerous biotransformations and artificial photosynthesis. Its high cost necessitates its regeneration for reuse where photocatalysis using light energy is attractive. However, high NAD(P)H yield is only achievable via organic mediators to transfer electrons. Here, we analyze the current issues in catalytic NAD(P)H regeneration and show that a continuous-flow reactor system can realize selective NAD(P)H regeneration with 100% yield using Pt/C3N4 as a photocatalyst

BAsE-Seq: a method for obtaining long viral haplotypes from short sequence reads.

We present a method for obtaining long haplotypes, of over 3 kb in length, using a short-read sequencer, Barcode-directed Assembly for Extra-long Sequences (BAsE-Seq). BAsE-Seq relies on transposing a template-specific barcode onto random segments of the template molecule and assembling the barcoded short reads into complete haplotypes. We applied BAsE-Seq on mixed clones of hepatitis B virus and accurately identified haplotypes occurring at frequencies greater than or equal to 0.4%, with >99.9% specificity. Applying BAsE-Seq to a clinical sample, we obtained over 9,000 viral haplotypes, which provided an unprecedented view of hepatitis B virus population structure during chronic infection. BAsE-Seq is readily applicable for monitoring quasispecies evolution in viral diseases

Target‐oriented habitat and wildlife management: estimating forage quantity and quality of semi‐natural grasslands with Sentinel‐1 and Sentinel‐2 data

Semi‐natural grasslands represent ecosystems with high biodiversity. Their conservation depends on the removal of biomass, for example, through grazing by livestock or wildlife. For this, spatially explicit information about grassland forage quantity and quality is a prerequisite for efficient management. The recent advancements of the Sentinel satellite mission offer new possibilities to support the conservation of semi‐natural grasslands. In this study, the combined use of radar (Sentinel‐1) and multispectral (Sentinel‐2) data to predict forage quantity and quality indicators of semi‐natural grassland in Germany was investigated. Field data for organic acid detergent fibre concentration (oADF), crude protein concentration (CP), compressed sward height (CSH) and standing biomass dry weight (DM) collected between 2015 and 2017 were related to remote sensing data using the random forest regression algorithm. In total, 102 optical‐ and radar‐based predictor variables were used to derive an optimized dataset, maximizing the predictive power of the respective model. High R2 values were obtained for the grassland quality indicators oADF (R2 = 0.79, RMSE = 2.29%) and CP (R2 = 0.72, RMSE = 1.70%) using 15 and 8 predictor variables respectively. Lower R2 values were achieved for the quantity indicators CSH (R2 = 0.60, RMSE = 2.77 cm) and DM (R2 = 0.45, RMSE = 90.84 g/m²). A permutation‐based variable importance measure indicated a strong contribution of simple ratio‐based optical indices to the model performance. In particular, the ratios between the narrow near‐infrared and red‐edge region were among the most important variables. The model performance for oADF, CP and CSH was only marginally increased by adding Sentinel‐1 data. For DM, no positive effect on the model performance was observed by combining Sentinel‐1 and Sentinel‐2 data. Thus, optical Sentinel‐2 data might be sufficient to accurately predict forage quality, and to some extent also quantity indicators of semi‐natural grassland

Single-virion sequencing of lamivudine-treated HBV populations reveal population evolution dynamics and demographic history.

BACKGROUND: Viral populations are complex, dynamic, and fast evolving. The evolution of groups of closely related viruses in a competitive environment is termed quasispecies. To fully understand the role that quasispecies play in viral evolution, characterizing the trajectories of viral genotypes in an evolving population is the key. In particular, long-range haplotype information for thousands of individual viruses is critical; yet generating this information is non-trivial. Popular deep sequencing methods generate relatively short reads that do not preserve linkage information, while third generation sequencing methods have higher error rates that make detection of low frequency mutations a bioinformatics challenge. Here we applied BAsE-Seq, an Illumina-based single-virion sequencing technology, to eight samples from four chronic hepatitis B (CHB) patients - once before antiviral treatment and once after viral rebound due to resistance. RESULTS: With single-virion sequencing, we obtained 248-8796 single-virion sequences per sample, which allowed us to find evidence for both hard and soft selective sweeps. We were able to reconstruct population demographic history that was independently verified by clinically collected data. We further verified four of the samples independently through PacBio SMRT and Illumina Pooled deep sequencing. CONCLUSIONS: Overall, we showed that single-virion sequencing yields insight into viral evolution and population dynamics in an efficient and high throughput manner. We believe that single-virion sequencing is widely applicable to the study of viral evolution in the context of drug resistance and host adaptation, allows differentiation between soft or hard selective sweeps, and may be useful in the reconstruction of intra-host viral population demographic history