Pollen percentage thresholds of Abies alba based on 13-year annual records of pollen deposition in modified Tauber traps: perspectives of application to fossil situations

Abies alba (fir), a submontane tree from Central European mountains and uplands, is of special interest for palaeoecological and palaeoclimate interpretations due to its sensitivity to air and soil humidity. Its present distribution limit in the uplands of SE Poland is still a matter of debate. In the Holocene fir expanded to Poland very late, but early fir populations are supposed to occur in the Šumava Mts (Czech Republic). The study aims: to estimate pollen thresholds for fir presence/absence in Bohemia (Czech Republic) and Poland on the basis of modified Tauber pollen traps; to use these thresholds for tracing fir presence in two pollen diagrams from Poland (Słone and Bezedna lakes) in the border zone between the Roztocze region (with fir forest stands today) and Polesie (where fir has never played an important role); and to investigate how the percentage presence/absence threshold can be used to trace the occurrence and abundance of fir trees in the Šumava Mts based on the pollen diagrams of Rokytecká slat' and Mrtvý luh. The fir pollen thresholds estimated in terms of PAR (pollen accumulation rates or pollen influx) range from 843 (grains cm− 2 year− 1) (Roztocze) to 61 (Krkonoše) and 49 (Šumava). Percentage thresholds range from 0.3% in Krkonoše where fir trees are not present within 4 km to 22% in fir-dominated woodland of the Roztocze, providing evidence of strong underrepresentation of fir in the pollen deposition. Application of these percentage thresholds to the Słone and Bezedna pollen diagrams indicates that occurrence of fir in the region is possible from 3.5 cal ky BP onwards, though the evidence is not decisive. In the Šumava, a low representation of fir pollen (1–2%) reflecting presence of scattered fir trees was detected as early as ca. 7.0 cal ky BP.

Genotypic Resistance Tests Sequences Reveal the Role of Marginalized Populations in HIV-1 Transmission in Switzerland.

Targeting hard-to-reach/marginalized populations is essential for preventing HIV-transmission. A unique opportunity to identify such populations in Switzerland is provided by a database of all genotypic-resistance-tests from Switzerland, including both sequences from the Swiss HIV Cohort Study (SHCS) and non-cohort sequences. A phylogenetic tree was built using 11,127 SHCS and 2,875 Swiss non-SHCS sequences. Demographics were imputed for non-SHCS patients using a phylogenetic proximity approach. Factors associated with non-cohort outbreaks were determined using logistic regression. Non-B subtype (univariable odds-ratio (OR): 1.9; 95% confidence interval (CI): 1.8-2.1), female gender (OR: 1.6; 95% CI: 1.4-1.7), black ethnicity (OR: 1.9; 95% CI: 1.7-2.1) and heterosexual transmission group (OR:1.8; 95% CI: 1.6-2.0), were all associated with underrepresentation in the SHCS. We found 344 purely non-SHCS transmission clusters, however, these outbreaks were small (median 2, maximum 7 patients) with a strong overlap with the SHCS'. 65% of non-SHCS sequences were part of clusters composed of >= 50% SHCS sequences. Our data suggests that marginalized-populations are underrepresented in the SHCS. However, the limited size of outbreaks among non-SHCS patients in-care implies that no major HIV outbreak in Switzerland was missed by the SHCS surveillance. This study demonstrates the potential of sequence data to assess and extend the scope of infectious-disease surveillance.

Publication activities of German junior researchers in academic medicine: which factors impact impact factors?

Previous studies have shown medical students in Germany to have little interest in research while at the same time there is a lack of physician scientists. This study’s aim is to investigate factors influencing publication productivity of physicians during and after finishing their medical doctorate. We conducted a PubMed search for physicians having received their doctoral degree at Ludwig-Maxmilians-University Munich Faculty of Medicine between 2011 and 2013 (N = 924) and identified the appropriate impact factor (IF) for each journal the participants had published in. Gender, age, final grade of the doctorate, participation in a structured doctoral study program and joint publication activities between graduate and academic supervisor were defined as factors. For analyses we used nonparametric procedures. Men show significantly more publications than women. Before their doctoral graduation men publish 1.98 (SD ± 3.64) articles on average, women 1.15 (±2.67) (p < 0.0001, d = 0.27). After completion of the doctorate (up to 06/2015), 40 % of men still publish, while only 24.3 % of women (p < 0.0001, φ = 0.17) continue to publish. No differences were found concerning the value of IFs. Similar results were found regarding the variable ‘participation in a structured doctoral study program’. Until doctoral graduation, program participants publish 2.82 (±5.41) articles, whereas participants doing their doctorate individually only publish 1.39 (±2.87) articles (p < 0.0001, d = 0.46). These differences persist in publication activities after graduation (45.5 vs. 29.7 %, p = 0.008, φ = 0.09). A structured doctorate seems to have positive influence on IFs (4.33 ± 2.91 vs. 3.37 ± 2.82, p = 0.006, d = 0.34). Further significant results concern the variables ‘final grade’ and ‘age’: An early doctoral graduation and an excellent or very good grade for the doctoral thesis positively influence publication productivity. Finally, joint publication activities between the graduate and his/her academic supervisor result in significantly higher IFs (3.64 ± 3.03 vs. 2.84 ± 2.25, p = 0.007, d = 0.28). The study’s results support the assumption about women’s underrepresentation in science as well as the relevance of structured doctoral study programs for preparing and recruiting young academics in medicine for scientific careers. Promoting women and further development of structured doctoral study programs are highly recommended.