Evaluating Potential Spectral Impacts of Various Artificial Lights on Melatonin Suppression,Photosynthesis, and Star Visibility

Artificial light at night can be harmful to the environment, and interferes with fauna and flora, star visibility, and human health. To estimate the relative impact of a lighting device, its radiant power, angular photometry and detailed spectral power distribution have to be considered. In this paper we focus on the spectral power distribution. While specific spectral characteristics can be considered harmful during the night, they can be considered advantageous during the day. As an example, while blue-rich Metal Halide lamps can be problematic for human health, star visibility and vegetation photosynthesis during the night, they can be highly appropriate during the day for plant growth and light therapy. In this paper we propose three new indices to characterize lamp spectra. These indices have been designed to allow a quick estimation of the potential impact of a lamp spectrum on melatonin suppression, photosynthesis, and star visibility. We used these new indices to compare various lighting technologies objectively. We also considered the transformation of such indices according to the propagation of light into the atmosphere as a function of distance to the observer. Among other results, we found that low pressure sodium, phosphor-converted amber light emitting diodes (LED) and LED 2700 K lamps filtered with the new Ledtech’s Equilib filter showed a lower or equivalent potential impact on melatonin suppression and star visibility in comparison to high pressure sodium lamps. Low pressure sodium, LED 5000 K-filtered and LED 2700 K-filtered lamps had a lower impact on photosynthesis than did high pressure sodium lamps. Finally, we propose these indices as new standards for the lighting industry to be used in characterizing their lighting technologies. We hope that their use will favor the design of new environmentally and health-friendly lighting technologies.     

The rpb2 gene represents a viable alternative molecular marker for the analysis of environmental fungal communities

Although the commonly used internal transcribed spacer region of rDNA (ITS) is well suited for taxonomic identification of fungi, the information on the relative abundance of taxa and diversity is negatively affected by the multicopy nature of rDNA and the existence of ITS paralogues. Moreover, due to high variability, ITS sequences cannot be used for phylogenetic analyses of unrelated taxa. The part of single‐copy gene encoding the second largest subunit of RNA polymerase II (rpb2) was thus compared with first spacer of ITS as an alternative marker for the analysis of fungal communities in spruce forest topsoil, and their applicability was tested on a comprehensive mock community. In soil, rpb2 exhibited broad taxonomic coverage of the entire fungal tree of life including basal fungal lineages. The gene exhibited sufficient variation for the use in phylogenetic analyses and taxonomic assignments, although it amplifies also paralogues. The fungal taxon spectra obtained with rbp2 region and ITS1 corresponded, but sequence abundance differed widely, especially in the basal lineages. The proportions of OTU counts and read counts of major fungal groups were close to the reality when rpb2 was used as a molecular marker while they were strongly biased towards the Basidiomycota when using the ITS primers ITS1/ITS4. Although the taxonomic placement of rbp2 sequences is currently more difficult than that of the ITS sequences, its discriminative power, quantitative representation of community composition and suitability for phylogenetic analyses represent significant advantages.     

A Combination of CD28 (rs1980422) and IRF5 (rs10488631) Polymorphisms Is Associated with Seropositivity in Rheumatoid Arthritis: A Case Control Study

IntroductionThe aim of the study was to analyse genetic architecture of RA by utilizing multiparametric statistical methods such as linear discriminant analysis (LDA) and redundancy analysis (RDA).MethodsA total of 1393 volunteers, 499 patients with RA and 894 healthy controls were included in the study. The presence of shared epitope (SE) in HLA-DRB1 and 11 SNPs (PTPN22 C/T (rs2476601), STAT4 G/T (rs7574865), CTLA4 A/G (rs3087243), TRAF1/C5 A/G (rs3761847), IRF5 T/C (rs10488631), TNFAIP3 C/T (rs5029937), AFF3 A/T (rs11676922), PADI4 C/T (rs2240340), CD28 T/C (rs1980422), CSK G/A (rs34933034) and FCGR3A A/C (rs396991), rheumatoid factor (RF), anti–citrullinated protein antibodies (ACPA) and clinical status was analysed using the LDA and RDA.ResultsHLA-DRB1, PTPN22, STAT4, IRF5 and PADI4 significantly discriminated between RA patients and healthy controls in LDA. The correlation between RA diagnosis and the explanatory variables in the model was 0.328 (Trace = 0.107; F = 13.715; P = 0.0002). The risk variants of IRF5 and CD28 genes were found to be common determinants for seropositivity in RDA, while positivity of RF alone was associated with the CTLA4 risk variant in heterozygous form. The correlation between serologic status and genetic determinants on the 1st ordinal axis was 0.468, and 0.145 on the 2nd one (Trace = 0.179; F = 6.135; P = 0.001). The risk alleles in AFF3 gene together with the presence of ACPA were associated with higher clinical severity of RA.ConclusionsThe association among multiple risk variants related to T cell receptor signalling with seropositivity may play an important role in distinct clinical phenotypes of RA. Our study demonstrates that multiparametric analyses represent a powerful tool for investigation of mutual relationships of potential risk factors in complex diseases such as RA.     

Effects of freezing on white perch Morone americana (Gmelin, 1789): implications for multivariate morphometrics

This study tested the hypothesis that duration of freezing differentially affects whole‐body morphometrics of a derived teleost. Whole‐body morphometrics are frequently analyzed to test hypotheses of different species, or stocks within a species, of fishes. Specimens used for morphometric analyses are typically fixed or preserved prior to analysis, yet little research has been done on how fixation or preservation methods or duration of preservation of specimens might affect outcomes of multivariate statistical analyses of differences in shape. To determine whether whole‐body morphometrics changed as a result of freezing, 23 whole‐body morphometrics of age‐1 white perch (Morone americana) from western Lake Erie (n = 211) were analyzed immediately after capture, after being held on ice overnight, and after freezing for 100 or 200 days. Discriminant function analysis revealed that all four groups differed significantly from one another (P < 0.0001). The first canonical axis reflected long‐axis morphometrics, where there was a clear pattern of positive translation along this axis with duration of preservation. Re‐classification analysis demonstrated fish were typically assigned to their original preservation class except for fish frozen 100 days, which assigned mostly to frozen 200 days. Morphometric comparisons using frozen fish must be done on fish frozen for identical periods of time to avoid biases related to the length of time they were frozen. Similar experiments should be conducted on other species and also using formalin‐ and alcohol‐preserved specimens.