Placoid and polyodontode scales of stem chondrichthyans have been found in the early Lochkovian “Ditton
Group” of the Brown Clee Hill district, Shropshire, England and at Talgarth, south Wales. One of the forms is
assigned to a new species of Altholepis Karatajūtė-Talimaa, 1997, a genus already recognised from Lochkovian
shallow marine deposits in Celtiberia, Spain and the Northwest Territories, Canada as well as the type locality in
Podolia, Ukraine. Altholepis salopensis sp. nov. is based on small polyodontode scales with typically three to eight
high odontodes; the scale form was previously considered to belong to acanthodian “Nostolepis” robusta (Brotzen,
1934). The structure of other scales formerly assigned to “Nostolepis” robusta has led us to erect a new genus
Jolepis for this scale form, which differs from Altholepis in lacking an ordered layout of odontodes. Jolepis robusta
(Brotzen, 1934), originally (and possibly still) considered to be an acanthodian, is also known from the Baltic
countries, Russia, and northern Germany (ex erratic limestones). Scales of acanthodian Parexus recurvus Agassiz,
1845, and/or possibly from the stem chondrichthyan Seretolepis elegans Karatajūtė-Talimaa, 1968 (scales of these
two taxa are barely distinguishable), and of stem chondrichthyan Polymerolepis whitei Karatajūtė-Talimaa, 1968
are also present. Altholepis, Jolepis gen. nov., Seretolepis Karatajūtė-Talimaa, 1968 and Polymerolepis Karatajūtė-
Talimaa, 1968 are found in marine deposits elsewhere; the British occurrence of these taxa adds to the debate on
the sedimentological origins of the Lower Old Red Sandstone deposits in the Welsh Borderland. The geographic
range of several early sharks is now known to extend around the Old Red Sandstone continent and beyond.
Stem cells exist and can do a lot. For several decades, bone marrow and umbilical cord blood transplants containing haematopoietic stem cells have been used in the treatment of blood diseases. Genetic modifications (gene therapy) of such cells help to cure complex immunodeficiencies and severe anaemias. The limbal stem cells taken from the eye and properly multiplied can regenerate the damaged cornea, and the epidermal stem cells help in the treatment of severe burns and some hereditary, severe skin diseases. Promising experimental research is under way on other uses of stem cells. However, these cells are appropriately selected, having real ability to differentiate into specialized cells whose malfunction is the cause of the disease. Therapeutic applications of stem cells are apparently limited to date. Meanwhile, the Internet is full of advertisements for supposedly miraculous treatments for almost any disease. Stem cells have become a modern synonym of the Holy Grail. A wonderful dish, transforming every drink into elixir of health, youth and long life. Stem cells from a single source, e.g., umbilical cord blood, or so-called cells, although without proven properties of stem cells, are offered in commercial private clinics as a panacea for autism, cerebral palsy, spina bifida, eye diseases, amyotrophic lateral sclerosis and dozens other disorders. Without justification for their action in these diseases, without convincing evidence of safety, but for a high fee. This article discusses stem cells and misunderstandings about including any cells among them. It draws attention to the real possibilities and confirmed uses of stem cells and presents the problems, doubts and dangers for patients associated with commercial offers of treatments using “stem” cells. The author cites the positions of scientific institutions and societies warning against premature commercialization of unjustified and potentially dangerous therapies.
The aim of the study was to compare the effects of corneal healing in case of application of stem cells in various forms, in relation to the antibiotic-assisted procedures. Rabbits were divided into 4 groups in the first stage of the experiment. Group 0 (negative control group) was not subjected to any actions, which would cause damage to the cornea. The remaining three groups had their cornea damaged. Group 1 (positive control group) – no drugs were administered during the experiment. Rabbits in group 2 were administered with ointment containing stem cells to the lesion, while group 3 – with ofloxacinum. The stem cells were administered during the first five days, twice a day, onto the corneal surface. The further course of the experiment consisted of observing the rate of healing of the injured cornea and assessment of its transparency, size of lesion, hyperaemia, eyelid spasm and outflow from the conjunctival sac after 5, 10 and 20 days.
In the second stage the animals were euthanised after clinical examination on the twentieth day of the experiment, in order to analyse the corneal reparative processes on the same day. The studies revealed that the application of antlerogenic stem cells had a positive effect on the healing process of corneal defects. The application thereof not only shortened the healing time, but also weakened or arrested the development of side effects. The results have demonstrated that the epithelial proliferation in each group was different. The longest was maintained in the group with stem cells, the shortest – in the group with chemotherapeutics. The use of antlerogenic stem cells had a positive effect on the healing process of corneal lesions. The use of stem cells helped to maintain high transparency of the cornea.
Biological activity of 6 fungicides in the inhibition of Phytophthora ramorum sporulation and development of blight on rhododendron leaves and stems were evaluated. All tested compounds at dose 8 μg o fa.i./cm3 already inhibited zoosporangia formation at least in 73%. On leaf petioles and leaf disks, taken from rhododendron one week after treatment with fungicides, formation of chlamydospores was especially suppressed by fenamidone + phosetyl Al and oxadixyl + mancozeb whereas development o fspores was not inhibited by cymoxanil + famoxate. All tested compounds significantly inhibited the development and spread of twig blight on rhododendron. However, furalaxyl, applied as spraying of plants 48 hrs before or after inoculation of leaves and stems by P. ramorum was the most effective.
Stemming plugs are one of the widely used accessory in surface mining operations. Stemming plugs assist conventional stemming material in gas retention and help in better fragmentation and explosive utilization. Effective use of the stemming plugs results in economic benefits and enhance the efficacy of the project. Economic and productive viability of stemming plugs have been conducted in depth by different researchers. Addition of stemming plugs to a new system requires ergonomic challenges for operators conducting drilling and blasting operation. Induction of a newer product in already established system is subject to overall positive feedback. This work investigates ergonomics of three different stemming plugs introduced to a limestone quarry in Pakistan. The stemming plugs were evaluated based on extra time needed, workers feedback, failures during operation, recovery time after failure and number of extra equipment required to carry out the operation. Points based matrix was established with likeliness of each plug and based on overall scores stemming plug 1 was most acceptable followed by stemming plug 3. Stemming plug 2 was disliked by operation and did not reach the level of acceptability of operators. This work will help stemming plug making industry in adapting to best practices by incorporating ergonomics of plugs in designing. Literature shows no previous work on ergonomics of stemming plugs.
This study was undertaken to investigate the effect of severe plastic deformation (SPD) by extrusion combined with reversible torsion (KoBo) method on microstructure and mechanical properties of Al-5Cu and Al-25Cu alloys. The extrusion combined with reversible torsion was carried out using reduction coefficient of λ = 30 and λ = 98. In this work, the microstructure was characterized by light microscopy (LM), scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM). Compression test and tensile test were performed for deformed alloys. The binary Al-5Cu and Al-25Cu alloys consist of the face cantered cubic (FCC) α phase in the form of dendrites and tetragonal (C16) θ-Al2Cu intermetallic phase observed in interdentritic regions. The increase of Cu content leads to increase of interdentritic regions. The microstructure of the alloys is refined after applying KoB deformation with λ = 30 and λ = 98. Ultimate Tensile Strength (UTS) of Al-5Cu alloy after KoBo deformation with λ = 30 and λ = 98 reached about 200 MPa. UTS for samples of Al-25Cu with λ = 30 and λ = 98 increased compared to Al-5Cu alloy and exceed 320 MPa and 270 MPa respectively. All samples showed increase of plasticity with increase of reduction coefficient. Independently of reduction coefficient, the compressive strain of Al-5Cu alloys is about 60%. The Al-25Cu alloy with λ = 98 showed the value of compressive strain exceed 60%, although for this same alloy but with λ = 30, the compressive strain is only 35%.
The incidence of winter wheat stem base diseases: Fusarium foot rot (Fusarium spp.), eyespot (Ramulispora herpotrichoides), sharp eyespot (Rhizoctonia spp.) and take-all (Gaeumannomyces graminis) in the years 1999–2003 was assessed in this study. Previous crops were barley and oilseed rape. Eyespot occurred on the greatest percentage of plants throughout the whole period of the study. In 2000–2003 a deficiency of rainfall was observed, especially at the time of increased water requirements of plants.
A survey was conducted in February of 2004 on the outbreak of stem rot and wilt disease of pepper at the Kitabawa/Danzakara and Ajiwa irrigation sites in Northern Nigeria. Laboratory investigations revealed that it was elicited by Phytophthora capsici Leon. The disease caused severe loss in yield and USD 1 700.00 to USD 3 200.00 loss in revenue/ha. The disease was probably further aggravated by the presence of Fusarium sp. as well as ecto- and endoparasitic nematodes. Reasons for outbreak were elucidated and solutions proffered.
Design of gating system is an important factor in obtaining defect-free casting. One of the casting defects is a porosity caused by internal
shrinkage in solidification process. Prediction of the internal shrinkage porosity in the femoral stem of commercially pure titanium (CP-Ti)
is investigated based on the gating system design. The objective of this research is to get the best gating system between three gating
system designs. Three gating system designs of the femoral stem were simulated in an investment casting method. The internal shrinkage
porosity occurs on the largest part and near the ingate of the femoral stem. The gating system design that has ingates cross section area:
78.5; 157; and 128.5 mm2
has the least of the internal shrinkage porosity. This design has the most uniform solidification in the entire of
the femoral stem. An experiment is conducted to validate the simulation data. The results of internal shrinkage porosity in the three gating
system designs in the simulation were compared with the experiment. Based on the comparison, the trend of internal shrinkage porosity at
the three gating system designs in the simulation agrees with the experiment. The results of this study will aid in the elimination of casting
defect.
The association of phytoplasma was investigated in sand olive [Dodonaea viscosa ssp. Angustifolia (L. f.) J.G. West], cowpea [Vigna unguiclata (L.)] Wap and alfalfa (Medicago sativa L.) plants exhibiting witches broom, fasciation and little leaf symptoms, respectively. Sequence analysis of ~1.7 kb DNA fragments amplified by P1/P7 primer set confirmed the association of ‘Candidatus Phytoplasma aurantifolia’ within symptomatic alfalfa, while ‘Ca. Phytoplasma cynodontis’ was associated within cowpea and sand olive.
New solutions in plant protection applications are still highly desirable. Aiming at higher efficiency, environmental safety and profitability of production which, in addition to reducing the costs of the application of plant protection products, limits the destruction of soil structure combined use of agrochemicals seems to be one of the most important method in modern agriculture. In 2016 and 2017, the Plant Protection Institute – National Research Institute in Poznań, Poland, conducted field experiments on the possibility of combining two popular herbicides used to control monocotyledonous weeds: pinoxaden and fenoxaprop-P-ethyl, with a two-component plant growth and development regulator (mepiquat chloride and prohexadione calcium) on KWS Ozon winter wheat. The tested substances were applied at the BBCH 24 stage of winter wheat – herbicide only, and at the BBCH 31 stage – a mix of herbicides with a plant growth and development regulator. Regardless of the method of application of pinoxaden (herbicide only or mixed), high effectiveness of Apera spica-venti control was obtained in both years of the study. The mix of pinoxaden with mepiquat chloride and prohexadione calcium reduced the wheat crop height to a similar extent as separate application of the substances. The combined application of fenoxaprop-P-ethyl with mepiquat chloride improved the effectiveness of wheat crop height control. The method of application of the substances had no significant effect on winter wheat yield. Grain yields harvested from plots treated with the above substances were significantly higher than control only in the case of high weed infestation of winter wheat. The technological value of wheat grain depended on the year of study, while the method of application did not have a significant impact on the evaluated parameters.
Telomerase reverse transcriptase (TERT) vectors were transfected into bone marrow mesen- chymal stem cells (BMSCs) which were then cultured and selected to establish TERT-BMSC cell lines whilst sequencing BMSCs and TERT-BMSCs via transcriptome in this study to explore their regulatory mechanism and effect on osteogenic differentiation after TERT ectopic expres- sion in sheep BMSCs. After sequencing and analysing differential genes, PI3K/Akt signalling pathway related to osteogenic differentiation was investigated. Western blot was used before and after applying the PI3K/Akt signalling pathway inhibitor LY294002 to detect protein expression levels of AKT and p-AKT. On the twenty-first day of osteogenic differentiation, RT-qPCR and Western blot were used to detect mRNA and protein expression levels of RUNX2 and OPN and alizarin red staining was utilised to analyse calcium salt deposition. Results showed that pro- tein expression levels of AKT and p-AKT were significantly up-regulated, mRNA and protein expression levels of RUNX2 and OPN increased and calcium salt deposition increased after ectopic expression of TERT. After applying LY294002, the protein expression of AKT and p-AKT was down-regulated, mRNA and protein expression levels of RUNX2 and OPN were reduced and calcium salt deposition was reduced. These results confirmed the stable integration and expression of the exogenous TERT gene in BMSCs to promote the differentiation of BMSC osteoblasts, which may be mediated by the PI3K/Akt signalling pathway.
Emerging researches in humans, pigs and mice, highlighted that estrogen plays a pivotal role in self-renewal and differentiation of bone marrow mesenchymal stem cells (BMSCs). The present study aimed at evaluating effects of 17 beta-estradiol (E2) on proliferation and apoptosis of canine-derived bone marrow mesenchymal stem cells (cBMSCs) in vitro. The results showed that E2 supplementation at the concentration of 10-11 M promoted the proliferation of cBMSCs by CCK-8 assay and RT-qPCR analysis for the proliferation-related genes, with proliferating cell nuclear antigen (PCNA), cyclin-D1 (CCND1) being up-regulated and cyclin-dependent kinase inhibitor 1B (CDKN1B) being down-regulated. Contrarily, analysis of fluorescence-activated cell sorting (FACS) and RT-qPCR demonstrated that E2 supplementation above 10-11 M had inhibitory effects on the proliferation of cBMSCs and induced apoptosis. Intriguingly, cBMSCs still possessed the capability to differentiate into osteoblasts and adipocytes with 10-11 M E2 addition. Taken together, this study determined the optimal culture condition of cBMSCs in vitro, and has important implications for further understanding the regulatory effect of E2 on the self-renewal of cBMSCs, which are helpful for the clinical application of BMSCs.
Two strength-age hardening aluminum-lithium alloys: Al-2.3wt%Li and Al-2.2wt%Li-0.1wt%Zr in two different heat treatment conditions: solution state (S) and additionally in aging state (A) were severely plastically deformed by rolling with cyclic movement of rolls (RCMR) method to produce ultrafine – grained structure. Two thermo-mechanical treatments were used: (S+A+RCMR) and (S+RCMR+A+RCMR). To investigate the combined effect of plastic deformation and heat treatment, tensile tests were performed. Microstructural observations were undertaken using scanning transmission electron microscopy (STEM), and scanning transmission electron microscopy (SEM) equipped with electron backscattering diffraction detector (EBSD). Based on the obtained results, it can be deduced that maximum mechanical properties as: yield strength (YS) and ultimate tensile strength (UTS) could be achieved when the microstructure of alloys is in (S+A+RCMR) state. For samples in (S+RCMR+A+RCMR) state, ductility is higher than for (S+A+RCMR) state. The microstructural results shows that the favourable conditions for decreasing grain size of alloys is (S+A+RCMR) state. Additionally, in this state is much greater dislocation density than for (S+RCMR+A+RCMR) state. The microstructure of alloys in (S+RCMR+A+RCMR) state is characterized by grains/subgrains with higher average diameter and with higher misorientation angles compared with (S+A+RCMR) state.
Knowledge of uterine fibroids has existed since the time of Hippocrates. However, there are still wide gaps in the understanding of its pathogenesis. No single theory explains the background of uterine fibroid pathology, which affects more than 50% of women worldwide. By contrast, a newly depicted cell type called telocytes was only recently identified in the past twenty years. Th ese cells have evoked ambivalent opinions in the scientific community. The unique features of telocytes coupled with experimental evidence by numerous researchers and our hypotheses and conceptions are discussed in this review. We emphasize the main telocyte interactions in the context of the uterine fibroid architecture. This review reveals the pivotal role of telocytes, describing their contacts with smooth muscle cells, fibroblasts, vessels and nerves, inflammatory cells and stem cells. Our data are based on the latest publications and our own results.
Field surveys were performed in winter and spring rape crops of agricultural companies and individual farmers during the period of 2001–2003. A questionnaire was completed for each experimental field, giving a description of the crop. The incidence and severity of fungal diseases were estimated annually in 14–18 winter and spring rape crops. Seed samples were taken from each field and composition fungal communities on harvested seed was estimated. Alternaria blight and Phoma stem canker were present on stems of all investigated winter and spring rape cultivars and Alternaria blight occurred on siliques in all experimental years. In 2001, most favourable year for spread of diseases, Alternaria blight damaged 87.2 100% of winter rape and 100% of spring rape siliques, maximum disease severity was 6.66 and 7.24%, respectively. All cultivars of winter and spring rape were susceptible to Alternaria blight. Phoma stem canker was more often found on stems of spring oilseed rape – up to 98% of stems with symptoms of Phoma stem canker. Seed fungal infection level was 10.0–100% in winter rape and 16.0–93.6% in spring rape seed samples. The most frequent fungi on seeds of winter and spring oilseed rape were Alternaria spp. and Cladosporium spp.