54 research outputs found
Diatoms from the genus Achnanthidium in flowing waters of the Appalachian Mountains (North America): Ecology, distribution and taxonomic notes
AbstractDiatoms from the genus Achnanthidium are abundant in rivers, streams, and springs of the Appalachian Mountains. They inhabit clean and polluted waters, including those affected by acid mine drainage. The identification of Achnanthidium taxa is difficult due to their small cell size and insufficient information in the diatom floras. We studied the taxonomy and ecology of Achnanthidium in Appalachian rivers by analyzing a data set of benthic diatom samples and corresponding water chemistry data collected during several water-quality surveys from 181 sampling sites. Ten species were identified using scanning electron and light microscopy: A. alpestre (Lowe & Kociolek) Lowe & Kociolek, A. atomus (Hustedt) Monnier, Lange-Bertalot, & Ector, A. deflexum (Reimer) Kingston, A. duthii (Sreenivasa) Edlund, A. eutrophilum (Lange-Bertalot) Lange-Bertalot, A. cf. gracillimum (Meister) Lange-Bertalot, A. cf. latecephalum Kobayasi, A. minutissimum (Kützing) Czarnecki (sensu lato), A. reimeri (Camburn) comb. nov., and A. rivulare Potapova & Ponader. The distribution of common taxa in relation to water chemistry was studied by fitting non-parametric regression models (generalized additive models, GAM, and non-parametric multiplicative regression models, NPMR) to species relative abundances. Studied Achnanthidium species differed considerably in their responses to water chemistry. These results suggest that species-level identifications will lead to more accurate bioassessments
A new species of Sellaphora (Sellaphoraceae) from Hannaberry Lake, Arkansas, U.S.A.
A new small-size species of Sellaphora was found in sediments from Hannaberry Lake, Arkansas, during the National Lakes Assessment project conducted by the United States Environmental Protection Agency. The species was studied with light microscopy and scanning electron microscopy. It differs from previously reported Sellaphora species by its small and delicate frustule with striation irresolvable in light microscopy. Here we present details on its morphology and size variation and report the characteristics of the lake where the species was found
Concerning Investigation of the Cultural Dyssinchrony of the Mental Development of Intellectually Gifted Teenagers. The Social Sciences
In the 21st century, the study of the culture impact on the mental development of a person is topical like never before. However, the cultural-psychological aspect of the personality formation is underinvestigated in the psychological science and practice. This is particularly so with the studies relating to the gifted teenagers. The gap in this area shall be filled with this study during which a set of psycho-diagnostic procedures was developed that also includes the author?s culturally-oriented questionnaire by V. V. Potapova. Totally, 412 teenagers were diagnosed. The performed research study of impact of culture including the ethnic culture on the mental development of the intellectually gifted teenagers was described. The ambivalent nature of this impact is emphasized: from socialization and mental regulation to neurotization of a personality. The scientific definition of the cultural dyssinchrony of the mental development and its types is marginal, mono-cultural, deep
Machine Learning Aided Photonic Diagnostic System for Minimally Invasive Optically Guided Surgery in the Hepatoduodenal Area
Abdominal cancer is a widely prevalent group of tumours with a high level of mortality if diagnosed at a late stage. Although the cancer death rates have in general declined over the past few decades, the mortality from tumours in the hepatoduodenal area has significantly increased in recent years. The broader use of minimal access surgery (MAS) for diagnostics and treatment can significantly improve the survival rate and quality of life of patients after surgery. This work aims to develop and characterise an appropriate technical implementation for tissue endogenous fluorescence (TEF) and assess the efficiency of machine learning methods for the real-time diagnosis of tumours in the hepatoduodenal area. In this paper, we present the results of the machine learning approach applied to the optically guided MAS. We have elaborated tissue fluorescence approach with a fibre-optic probe to record the TEF and blood perfusion parameters during MAS in patients with cancers in the hepatoduodenal area. The measurements from the laser Doppler flowmetry (LDF) channel were used as a sensor of the tissue vitality to reduce variability in TEF data. Also, we evaluated how the blood perfusion oscillations are changed in the tumour tissue. The evaluated amplitudes of the cardiac (0.6-1.6 Hz) and respiratory (0.2-0.6 Hz) oscillations was significantly higher in intact tissues (p < 0.001) compared to the cancerous ones, while the myogenic (0.2-0.06 Hz) oscillation did not demonstrate any statistically significant difference. Our results demonstrate that a fibre-optic TEF probe accompanied with ML algorithms such as k-Nearest Neighbours or AdaBoost is highly promising for the real-time in situ differentiation between cancerous and healthy tissues by detecting the information about the tissue type that is encoded in the fluorescence spectrum. Also, we show that the detection can be supplemented and enhanced by parallel collection and classification of blood perfusion oscillations
Morphology, ecology and biogeography of Stauroneis pachycephala P.T. Cleve (Bacillariophyta) and its transfer to the genusEnvekadea
Stauroneis pachycephala was described in 1881 from the Baakens River, Port Elizabeth, South Africa. Recently, it was found during surveys of the MacKenzie River (Victoria, Australia), the Florida Everglades (USA) and coastal marshes of Louisiana (USA). The morphology, ecology and geographic distribution of this species are described in this article. This naviculoid species is characterised by lanceolate valves with a gibbous centre, a sigmoid raphe, an axial area narrowing toward the valve ends, and capitate valve apices. The central area is a distinct stauros that is slightly widened near the valve margin. The raphe is straight and filiform, and the terminal raphe fissures are strongly deflected in opposite directions. Striae are fine and radiate in the middle of the valve, becoming parallel and eventually convergent toward the valve ends. The external surface of the valves and copulae is smooth and lacks ornamentation. We also examined the type material of S. pachycephala. Our observations show this species has morphological characteristics that fit within the genus Envekadea. Therefore, the transfer of S. pachycephala to Envekadea is proposed and a lectotype is designated
Magnetic therapy in acute and subacute non-specific back pain: Results of an open multicenter study
Magnetic therapy (MT) is a non-drug method that improves the effectiveness of treatment of musculoskeletal pain, including:acute non-specific back pain (NBP). Objective of our study was to evaluate the results of complex treatment of patients with acute/subacute NBP at home using MT. The study group consisted of 339 patients with severe acute/subacute NBP. All patients received nonsteroidal anti-inflammatory drugs (NSAIDs). 166 patients (Group 1) received a course of MT (ALMAG+ device), 173 patients or a control group (Group 2) who did not receive MT. The dynamics of pain was significantly higher in group 1 than in group 2. So, the intensity of pain during movement (NRS) decreased from 7 [5;8] and 7 [5;8] to 0 [0;13] and 2 [1;3] after 1 month. (p<0.001). Significant differences between Groups 1 and 2 were observed in the dynamics of pain at rest and at night, overall health assessment (OHA), and sleep function and disorders. The average duration of NSAIDs use in Group 1 was 8.8±3.9, Group 2 – 11.8±5.7 days (p<0.001). The use of MT increases the effectiveness of treatment of acute/subacute NBP and reduces the need for NSAIDs use
CDK-1 inhibits meiotic spindle shortening and dynein-dependent spindle rotation in C. elegans
Before chromosome expulsion into polar bodies during female meiosis, the APC inhibits CDK-1 to allow dynein-driven spindle rotation
Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples
Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts
Geologia como uma ciência histórica da natureza
A geologia como ciência teórica está sem dúvida passando por uma de suas crises de crescimento. Isto é visto, em particular, nas contribuições contraditórias sobre seu objeto, conteúdo e método. Ouvem-se proposições de que a noção de geologia como uma ciência que trata da história da Terra há muito tornou-se antiquada, que a Geofísica, a Geoquímica e outras são as únicas ciências teóricas da Terra
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