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The African shieldbug genus Afrius Stål, 1870 is revised. Cantheconidea migratoria Distant, 1913 and A. williamsi Miller, 1952 are proposed as junior synonyms of A. (Subafrius) flavirostrum (Signoret, 1861) whereas Canthecona marmorata Dallas, 1851, Canthecona annulipes Dallas, 1851 and A. rubromarginatus Bergroth, 1903 are proposed as junior synonyms of A. (Afrius) purpureus (Westwood, 1837) based on the general morphology and genitalia of the species. The three valid species, viz. A. (Subafrius) flavirostrum, A. (Afrius) kolleri Schouteden, 1911 and A. (Afrius) purpureus, are redescribed with details of male and female genitalia morphology, and a lectotype is designated for A. (Afrius) kolleri. A key to identify the species as well as an update of the geographical distribution for each species are provided, including new records for A. (Afrius) purpureus.
We have encountered two polymorphs of the title compound, C24H16B2OS2, both of which display almost the same unit-cell parameters. Compound (I) crystallizes in the non-centrosymmetric space group P21 with four molecules in the asymmetric unit. These molecules are related by pseudosymmetry. As a result, the space group looks like P21/c, but the structure cannot be refined successfully in that space group. Compound (II) on the other hand crystallizes in the centrosymmetric space group P21/c with only two molecules in the asymmetric unit. The crystals studied for (I) and (II) were both non-merohedral twins.
Inositol, 1,2,3,4,5,6-hexahydroxycyclohexane, exists in nine stereoisomers with different crystal structures and melting points. In a previous paper on the relationship between the melting points of the inositols and the hydrogen-bonding patterns in their crystal structures [Simperler et al. (2006[Simperler, A., Watt, S. W., Bonnet, P. A., Jones, W. & Motherwell, W. D. S. (2006). CrystEngComm, 8, 589-600.]). CrystEngComm 8, 589], it was noted that although all inositol crystal structures known at that time contained 12 hydrogen bonds per molecule, their melting points span a large range of about 170 °C. Our preliminary investigations suggested that the highest melting point must be corrected for the effect of molecular symmetry, and that the three lowest melting points may need to be revised. This prompted a full investigation, with additional experiments on six of the nine inositols. Thirteen new phases were discovered; for all of these their crystal structures were examined. The crystal structures of eight ordered phases could be determined, of which seven were obtained from laboratory X-ray powder diffraction data. Five additional phases turned out to be rotator phases and only their unit cells could be determined. Two previously unknown melting points were measured, as well as most enthalpies of melting. Several previously reported melting points were shown to be solid-to-solid phase transitions or decomposition points. Our experiments have revealed a complex picture of phases, rotator phases and phase transitions, in which a simple correlation between melting points and hydrogen-bonding patterns is not feasible.
To better understand the dung beetle (Coleoptera: Scarabaeidae: Scarabaeinae) biodiversity of Costa Rica and Panama, new synonyms, records, distributions, and updates are presented. This paper analyzes the distribution and taxonomy of Phanaeus olsoufieffi Balthasar, 1939 in Panama and establishes the following new subjective synonym: Phanaeus panamensis Moctezuma and Halffter, 2021 = Phanaeus olsoufieffi Balthasar, 1939. Color morphs of Phanaeus pyrois Bates, 1887 in Costa Rica are analyzed. The Costa Rican distribution of Onthophagus bidentatus Drapiez, 1819 and O. marginicollis Harold, 1880 is studied. Onthophagus bidentatus is recorded for Costa Rica for the first time. A population analysis of barcode mtDNA, color morphs, and morphological and genitalia characters for different body sizes of Onthophagus cyanellus is undertaken. An mtDNA barcode tree is presented to assess the molecular identity of O. cyanellus resulting in the reaffirmed subjective synonymy, Onthophagus mesoamericanus Zunino and Halffter, 1988 = O. cyanellus Bates, 1887.
ZooBank registration. urn:lsid:zoobank.org:pub:E701D60F-A455-4048-8279-DA450930ACB3
Summary
Wild relatives of crops thrive in habitats where environmental conditions can be restrictive for productivity and survival of cultivated species. The genetic basis of this variability, particularly for tolerance to high temperatures, is not well understood. We examined the capacity of wild and cultivated accessions to acclimate to rapid temperature elevations that cause heat stress (HS).
We investigated genotypic variation in thermotolerance of seedlings of wild and cultivated accessions. The contribution of polymorphisms associated with thermotolerance variation was examined regarding alterations in function of the identified gene.
We show that tomato germplasm underwent a progressive loss of acclimation to strong temperature elevations. Sensitivity is associated with intronic polymorphisms in the HS transcription factor HsfA2 which affect the splicing efficiency of its pre‐mRNA. Intron splicing in wild species results in increased synthesis of isoform HsfA2‐II, implicated in the early stress response, at the expense of HsfA2‐I which is involved in establishing short‐term acclimation and thermotolerance.
We propose that the selection for modern HsfA2 haplotypes reduced the ability of cultivated tomatoes to rapidly acclimate to temperature elevations, but enhanced their short‐term acclimation capacity. Hence, we provide evidence that alternative splicing has a central role in the definition of plant fitness plasticity to stressful conditions.
This paper reviews little-known species of the dysderid spider genera Dysdera Latreille, 1804, and Dysderella Dunin, 1992 based on specimens collected in the Caucasus, Middle East, and Central Asia. After combining molecular phylogeny of five mitochondrial and three nuclear genes with morphological evidence, Dysderella is proposed as a junior synonym of Dysdera. In addition, three species are described as new to science: D. jaegeri Bellvert & Dimitrov sp. nov., D. naouelae Bellvert & Dimitrov sp. nov., and D. kourosh Bellvert, Zamani & Dimitrov sp. nov. Four combinations are proposed: Dysdera caspica Dunin, 1990 comb. rev., Dysdera transcaspica Dunin & Fet, 1985 comb. rev., Dysdera elburzica (Zamani, Marusik & Szűts, 2023) comb. nov. and Dysdera sancticedri (Brignoli, 1978) comb. nov. (ex. Dasumia Thorell, 1875). Furthermore, we report a first record of D. festai Caporiacco, 1929 in Turkey and its male cheliceral polymorphism. Our results illustrate the deficiencies that undermine the current taxonomy of this genus. For example, many species are described based on only one or few specimens or limited locality data. The advancements in DNA sequencing technologies applied to museum specimens reduce the need for fieldwork collection and export of fresh specimens. This highlights the significance of museum collections for improving research in this field.
The manifestation of chronic back pain depends on structural, psychosocial, occupational and genetic influences. Heritability estimates for back pain range from 30% to 45%. Genetic influences are caused by genes affecting intervertebral disc degeneration or the immune response and genes involved in pain perception, signalling and psychological processing. This inter-individual variability which is partly due to genetic differences would require an individualized pain management to prevent the transition from acute to chronic back pain or improve the outcome. The genetic profile may help to define patients at high risk for chronic pain. We summarize genetic factors that (i) impact on intervertebral disc stability, namely Collagen IX, COL9A3, COL11A1, COL11A2, COL1A1, aggrecan (AGAN), cartilage intermediate layer protein, vitamin D receptor, metalloproteinsase-3 (MMP3), MMP9, and thrombospondin-2, (ii) modify inflammation, namely interleukin-1 (IL-1) locus genes and IL-6 and (iii) and pain signalling namely guanine triphosphate (GTP) cyclohydrolase 1, catechol-O-methyltransferase, μ opioid receptor (OPMR1), melanocortin 1 receptor (MC1R), transient receptor potential channel A1 and fatty acid amide hydrolase and analgesic drug metabolism (cytochrome P450 [CYP]2D6, CYP2C9).
Hematotoxicity is one of the major side effects of chemotherapy. The aim of this study was to examine the association between single nucleotide polymorphisms (SNPs) and hematotoxicity in breast cancer patients in a subset of patients of the SUCCESS prospective phase III chemotherapy study. All patients (n = 1678) received three cycles of 5-fluorouracil, epirubicin, and cyclophosphamide (FEC) followed by three cycles of docetaxel or docetaxel/gemcitabine, depending on randomization. Germline DNA was genotyped for 246 SNPs selected from a previous genome-wide association study (GWAS) in a panel of lymphoblastoid cell lines, with gemcitabine toxicity as the phenotype. All SNPs were tested for their value in predicting grade 3 or 4 neutropenic or leukopenic events (NLEs). Their prognostic value in relation to overall survival and disease-free survival was also tested.
None of the SNPs was found to be predictive for NLEs during treatment with docetaxel/gemcitabine. Two SNPs in and close to the PIGB gene significantly improved the prediction of NLEs after FEC, in addition to the factors of age and body surface area. The top SNP (rs12050587) had an odds ratio of 1.38 per minor allele (95% confidence interval, 1.17 to 1.62). No associations were identified for predicting disease-free or overall survival.
Genetic variance in the PIGB gene may play a role in determining interindividual differences in relation to hematotoxicity after FEC chemotherapy.
A new pseudopolymorph of perchlorinated neopentasilane: the benzene monosolvate Si(SiCl3)4·C6H6
(2020)
A new pseudopolymorph of dodecachloropentasilane, namely a benzene monosolvate, Si5Cl12·C6H6, is described. There are two half molecules of each kind in the asymmetric unit. Both Si5Cl12 molecules are completed by crystallographic twofold symmetry. One of the benzene molecules is located on a twofold rotation axis with two C—H groups located on this rotation axis. The second benzene molecule has all atoms on a general position: it is disordered over two equally occupied orientations. No directional interactions beyond normal van der Waals contacts occur in the crystal.