A search for the lenses in the Herschel Bright Sources (HerBS) sample

Verifying that sub-mm galaxies are gravitationally lensed requires time-expensive observations with oversubscribed high-resolution observatories. Here, we aim to strengthen the evidence of gravitational lensing within the Herschel Bright Sources (HerBS) by cross-comparing their positions to optical (SDSS) and near-infrared (VIKING) surveys, in order to search for the foreground lensing galaxy candidates. Resolved observations of the brightest HerBS sources have already shown that most are lensed, and a galaxy evolution model predicts that ∼76 per cent of the total HerBS sources are lensed, although with the SDSS survey we are only able to identify the likely foreground lenses for 25 per cent of the sources. With the near-infrared VIKING survey, however, we are able to identify the likely foreground lenses for 57 per cent of the sources, and we estimate that 82 per cent of the HerBS sources have lenses on the VIKING images even if we cannot identify the lens in every case. We find that the angular offsets between lens and Herschel source are larger than that expected if the lensing is done by individual galaxies. We also find that the fraction of HerBS sources that are lensed falls with decreasing 500-micron flux density, which is expected from the galaxy evolution model. Finally, we apply our statistical VIKING cross-identification to the entire Herschel-ATLAS catalogue, where we also find that the number of lensed sources falls with decreasing 500-micron flux density

Genetic fine-mapping of DIPLOSPOROUS in Taraxacum (dandelion; Asteraceae) indicates a duplicated DIP-gene

Background DIPLOSPOROUS (DIP) is the locus for diplospory in Taraxacum, associated to unreduced female gamete formation in apomicts. Apomicts reproduce clonally through seeds, including apomeiosis, parthenogenesis, and autonomous or pseudogamous endosperm formation. In Taraxacum, diplospory results in first division restitution (FDR) nuclei, and inherits as a dominant, monogenic trait, independent from the other apomixis elements. A preliminary genetic linkage map indicated that the DIP-locus lacks suppression of recombination, which is unique among all other map-based cloning efforts of apomeiosis to date. FDR as well as apomixis as a whole are of interest in plant breeding, allowing for polyploidization and fixation of hybrid vigor, respectively. No dominant FDR or apomixis genes have yet been isolated. Here, we zoom-in to the DIP-locus by largely extending our initial mapping population, and by analyzing (local) suppression of recombination and allele sequence divergence (ASD). Results We identified 24 recombinants between two most closely linked molecular markers to DIP in an F1-population of 2227 plants that segregates for diplospory and lacks parthenogenesis. Both markers segregated c. 1:1 in the entire population, indicating a 1:1 segregation rate of diplospory. Fine-mapping showed three amplified fragment length polymorphisms (AFLPs) closest to DIP at 0.2 cM at one flank and a single AFLP at 0.4 cM at the other flank. Our data lacked strong evidence for ASD at marker regions close to DIP. An unexpected bias towards diplosporous plants among the recombinants (20 out of 24) was found. One third of these diplosporous recombinants showed incomplete penetrance of 50-85% diplospory. Conclusions Our data give interesting new insights into the structure of the diplospory locus in Taraxacum. We postulate a locus with a minimum of two DIP-genes and possibly including one or two enhancers or cis-regulatory elements on the basis of the bias towards diplosporous recombinants and incomplete penetrance of diplospory in some of them. We define the DIP-locus to 0.6 cM, which is estimated to cover ~200-300 Kb, with the closest marker at 0.2 cM. Our results confirm the minor role of suppression of recombination and ASD around DIP, making it an excellent candidate to isolate via a chromosome-walking approach.

The value of reasons for encounter in early detection of colorectal cancer

BACKGROUND: Symptoms with a high predictive power for colorectal cancer (CRC) do not exist. OBJECTIVE: To explore the predictive value of patients' reason for encounter (RFE) in the two years prior to the diagnosis of CRC. METHODS: A retrospective nested case-control study using prospectively collected data from electronic records in general practice over 20 years. Matching was done based on age (within two years), gender and practice. The positive likelihood ratios (LR+) and odds ratios (OR) were calculated for RFE between cases and controls in the two years before the index date. RESULTS: We identified 184 CRC cases and matched 366 controls. Six RFEs had significant LR + and ORs for CRC, which may have high predictive power. These RFEs are part of four chapters in the International Classification of Primary Care (ICPC) that include tiredness (significant at 3-6 months prior to the diagnosis; LR+ 2.6 and OR 3.07; and from 0 to 3 months prior to the diagnosis; LR+ 2.0 and OR 2.36), anaemia (significant at three months before diagnosis; LR+ 9.8 and OR 16.54), abdominal pain, rectal bleeding and constipation (significant at 3-6 months before diagnosis; LR+ 3.0 and OR 3.33; 3 months prior to the diagnosis LR+ 8.0 and OR 18.10) and weight loss (significant at three months before diagnosis; LR+ 14.9 and OR 14.53). CONCLUSION: Data capture and organization in ICPC permits study of the predictive value of RFE for CRC in primary care

Sexual and urinary functioning after rectal surgery: a prospective comparative study with a median follow-up of 8.5 years

The purpose of this study was to prospectively compare rectal resection (RR) with colonic resection on sexual, urinary and bowel function and quality of life in both short-term and long-term. Eighty-three patients who underwent RR were compared to 53 patients who underwent a colonic resection leaving the rectum in situ (RIS). A questionnaire assessing sexual, urinary and bowel functioning with a quality of life questionnaire (SF-36) was sent to all participants preoperatively, 3 and 12 months postoperatively and approximately 8 years after the onset of the study. Short-term dysfunction included diminished sexual activity in female RR patients at 3 months and significantly more erectile dysfunction in RR patients 1 year postoperatively. Long-term dysfunction included more frequent and more severe erectile dysfunction in RR patients compared to RIS patients. These short-term and long-term outcomes did not influence overall quality of life. The incidence of urinary dysfunction was comparable between both groups. Bowel functioning was significantly better in the RIS group compared to the RR group 3 months and 1 year postoperatively. Patients who underwent RR experienced up to 1 year postoperatively more sexual and bowel function problems than RIS patients. However, short-term and long-term dysfunction did not influence overall quality of life. Erectile dysfunction in male RR patients persisted in time, whereas other aspects of sexual, urinary and bowel function after RR and colonic resection are similar after a median follow-up of 8.5 year

Mass spectrometric fragmentation patterns discriminate C1- and C4-oxidised cello-oligosaccharides from their non-oxidised and reduced forms

Lytic polysaccharide monooxygenases (LPMOs) are powerful enzymes that degrade recalcitrant polysaccharides, such as cellulose. However, the identification of LPMO-generated C1- and/or C4-oxidised oligosaccharides is far from straightforward. In particular, their fragmentation patterns have not been well established when using mass spectrometry. Hence, we studied the fragmentation behaviours of non-, C1- and C4-oxidised cello-oligosaccharides, including their sodium borodeuteride-reduced forms, by using hydrophilic interaction chromatography and negative ion mode collision induced dissociation - mass spectrometry. Non-oxidised cello-oligosaccharides showed predominantly C- and A-type cleavages. In comparison, C4-oxidised ones underwent B-/Y- and X-cleavage close to the oxidised non-reducing end, while closer to the reducing end C-/Z- and A-fragmentation predominated. C1-oxidised cello-oligosaccharides showed extensively A-cleavage. Reduced oligosaccharides showed predominant glycosidic bond cleavage, both B-/Y- and C-/Z-, close to the non-reducing end. Our findings provide signature mass spectrometric fragmentation patterns to unambiguously elucidate the catalytic behaviour and classification of LPMOs.</p

Cell wall polysaccharides in black currants and bilberries-characterisation in berries, juice, and press cake

Abstract Cell wall polysaccharides from black currants and bilberries were characterised in three approaches. First, compositions of skin, pulp, and seeds show the distribution of polysaccharides over these tissues. A sequential extraction of cell wall material with different aqueous extractants informs about the extractability of the different polysaccharides, viz. pectins, hemicellulose, and cellulose. Finally, by isolation of cell wall polysaccharides from juice and press cakes obtained by the conventional juice manufacturing. The polysaccharide distribution was followed during juice processing. The main difference between bilberries and black currants is the dominant sugar residue in seeds: mannose for black currants and xylose for bilberries. Most of the hemicellulolytic sugars and cellulose can be found back in the press cake. The sugar composition of the press cake is similar to the composition of the residue after sequential extraction. Black currants contain more pectic sugars than bilberries. Consequently, a commercial enzyme used during processing releases more pectic material into the juice.

FLASH: Faint Lenses from Associated Selection with Herschel

We report the ALMA Band 7 observations of 86 Herschel sources that likely contain gravitationally-lensed galaxies. These sources are selected with relatively faint 500 $\mu$m flux densities between 15 to 85 mJy in an effort to characterize the effect of lensing across the entire million-source Herschel catalogue. These lensed candidates were identified by their close proximity to bright galaxies in the near-infrared VISTA Kilo-Degree Infrared Galaxy Survey (VIKING) survey. Our high-resolution observations (0.15 arcsec) confirm 47 per cent of the initial candidates as gravitational lenses, while lensing cannot be excluded across the remaining sample. We find average lensing masses (log M/M$_{\odot}$ = 12.9 $\pm$ 0.5) in line with previous experiments, although direct observations might struggle to identify the most massive foreground lenses across the remaining 53 per cent of the sample, particularly for lenses with larger Einstein radii. Our observations confirm previous indications that more lenses exist at low flux densities than expected from strong galaxy-galaxy lensing models alone, where the excess is likely due to additional contributions of cluster lenses and weak lensing. If we apply our method across the total 660 sqr. deg. H-ATLAS field, it would allow us to robustly identify 3000 gravitational lenses across the 660 square degree Herschel ATLAS fields.Comment: Accepted for publication in MNRAS. Comments and discussion are welcom