10 research outputs found
The secret chambers in the Chephren Pyramid
Pyramids are the greatest architectural achievement of ancient civilization,
so people all over the world are curious as to the purpose of such huge
constructions. No other structure has been studied as thoroughly, nor have so
many books and articles been written about it. We created a computer model of
the pyramid. To validate the model, we compare our calculations with the
experimental data of Luis W. Alvarez. The fact that the Egyptians set up 2.5
million stone blocks without any purpose seems to be unimaginable. Therefore,
we attempt to examine the internal structure of the pyramid using muon
tomography. With our measurements we performed and verified a calibration of
the attenuation of muons for primary beam momenta of 2.5 GeV/c and 3 GeV/c at
the T9 experimental area of CERN.Comment: The authors of the paper are winners of the CERN Beamline for Schools
2016 competition. To be submitted to the
journal Physics Educatio
Bufadienolides - natural, biologically active compounds for medicines and cosmetics. A review.
Toad skin secretions are a rich source of various biologically active compounds, such as alkaloids, bufadienolides, biogenic amines, or peptides. Also plants from Hyacinthaceae and Crassulaceae can be a potent source of these groups of molecules. These compounds play a crucial role in amphibians’ and plants’ physiology such as defense against predators or pathogenic microorganisms. Among them, bufadienolides are the focus of many researches in recent years. These molecules have a very interesting, steroidal chemical structure and have potent activity at the cellular level. They possess cardiotonic, antiviral, antibacterial, antitumor, anti-inflammatory, hemostatic, bacteriostatic, wound-healing, and antiparasitic properties. Although the structures of about 500 bufadienolides are known, it is strongly suggested that this group of compounds is still very poorly examined. Moreover, bufadienolides may be an excellent basis for the chemical synthesis of new drugs with selective bioactivity. The aim of this paper is to briefly overview bufadienolides as potent compounds for medicines and cosmetics
Toward the Analysis of Volatile Organic Compounds from Tomato Plants (<i>Solanum lycopersicum</i> L.) Treated with <i>Trichoderma virens</i> or/and <i>Botrytis cinerea</i>
Gray mold caused by Botrytis cinerea causes significant losses in tomato crops. B. cinerea infection may be halted by volatile organic compounds (VOCs), which may exhibit fungistatic activity or enhance the defense responses of plants against the pathogen. The enhanced VOC generation was observed in tomato (Solanum lycopersicum L.), with the soil-applied biocontrol agent Trichoderma virens (106 spores/1 g soil), which decreased the gray mold disease index in plant leaves at 72 hpi with B. cinerea suspension (1 × 106 spores/mL). The tomato leaves were found to emit 100 VOCs, annotated and putatively annotated, assigned to six classes by the headspace GCxGC TOF-MS method. In Trichoderma-treated plants with a decreased grey mold disease index, the increased emission or appearance of 2-hexenal, (2E,4E)-2,4-hexadienal, 2-hexyn-1-ol, 3,6,6-trimethyl-2-cyclohexen-1-one, 1-octen-3-ol, 1,5-octadien-3-ol, 2-octenal, octanal, 2-penten-1-ol, (Z)-6-nonenal, prenol, and acetophenone, and 2-hydroxyacetophenone, β-phellandrene, β-myrcene, 2-carene, δ-elemene, and isocaryophyllene, and β-ionone, 2-methyltetrahydrofuran, and 2-ethyl-, and 2-pentylfuran, ethyl, butyl, and hexyl acetate were most noticeable. This is the first report of the VOCs that were released by tomato plants treated with Trichoderma, which may be used in practice against B. cinerea, although this requires further analysis, including the complete identification of VOCs and determination of their potential as agents that are capable of the direct and indirect control of pathogens
Safety and efficacy of a Ventralight ST echo ps implant for a laparoscopic ventral hernia repair – a prospective cohort study with a one-year follow-up
Laparoscopic ventral hernia repair has become popular technique. Every year, companies are introducing new products Thus, every mesh prior to introduction in clinical settings should be tested with a dedicated tacker to discover the proper fixation algorithm. The aim of the study was to assess the safety and efficacy of the Ventralight ST implant with an ECHO positioning system and a dedicated fixation device, the SorbaFix stapler, in a prospective cohort of patients. Material and methods. The study was a prospective single centre cohort study with a one-year followup period. Fifty-two patients received operations for a ventral hernia using a laparoscopic IPOM mesh – Ventralight ST ECHO PS. The size of the mesh and the fixation method were based on mathematical considerations. A recurrence of the hernia and pain after 1, 2 and 12 months were assessed as the primary endpoints. Results. Two recurrences were noted, one in parastomal and one in a large incisional hernia. Pain was observed in 22 patients (41%) and mostly disappeared after 3 months (7%). The intensity of pain was low (VAS 6) until the end of the study. Conclusion. The Ventralight ST Echo PS implant fixed with a Sorbafix stapler is a valuable and safe option for a laparoscopic ventral hernia repair. In our opinion, the implant could be used in all patients due to the hernia ring diameter. According to the mathematical models and clinical practice, we do not recommend this implant in orifices with a width larger than 10 cm
Bezpieczeństwo i skuteczność zastosowania wewnątrzbrzusznego implantu Ventralight SY w laparoskopowym zaopatrzeniu przepuklin brzusznych – badanie prospektywne z rocznym okresem obserwacji
Celem badania była ocena bezpieczeństwa i skuteczności zastosowania implantu Ventralight ST z systemem pozycjonującym ECHO i dedykowanym urządzeniem mocującym – staplerem SorbaFix w prospektywnym badaniu kohortowym. Marteriał i metodyka. Badanie zaplanowano jako prospektywne jednoośrodkowe badanie kohorty chorych z jednorocznym okresem obserwacyjnym. Do badania włączono 52 chorych poddanych interwencji z powodu przepukliny brzusznej za pomocą laparoskopowego zaopatrzenia z implantem Ventralight ST ECHO PS. Wielkość siatki i sposób mocowania oparto na teoretycznych założeniach matematycznych. Głównym ocenianym parametrem było wystąpienie nawrotu w 12-miesięcznej obserwacji. Wyniki. Zanotowano dwa nawroty przepukliny, jeden u chorego z przepukliną okołostomijną i drugi w dużej przepuklinie pooperacyjnej. Ból obserwowano u 22 chorych (41%) po zabiegu. U większości chorych ból ustępował po okresie 3 miesięcy (7%). Obserwowano niskie natężenie bólu (VAS 6) w całym okresie obserwacji. Wnioski. Użycie implantu Ventralight ST Echo PS mocowanego stapleremSorbafix jest wartościową i bezpieczną opcją w laparoskopowym zaopatrzeniu przepukliny brzusznej. Rozwiązanie może być użyte do zaopatrzenia chorych zakwalifikowanych do laparoskopii z uwzględnieniem wielkości przepukliny. W odniesieniu do modeli matematycznych i przedstawionych danych klinicznych autorzy nie rekomendują używania opisanego implantu do przepuklin o pierścieniu większym niż 10 cm
Determination of Reactive Oxygen or Nitrogen Species and Novel Volatile Organic Compounds in the Defense Responses of Tomato Plants against Botrytis cinerea Induced by Trichoderma virens TRS 106
In the present study, Trichoderma virens TRS 106 decreased grey mould disease caused by Botrytis cinerea in tomato plants (S. lycopersicum L.) by enhancing their defense responses. Generally, plants belonging to the ‘Remiz’ variety, which were infected more effectively by B. cinerea than ‘Perkoz’ plants, generated more reactive molecules such as superoxide (O2−) and peroxynitrite (ONOO−), and less hydrogen peroxide (H2O2), S-nitrosothiols (SNO), and green leaf volatiles (GLV). Among the new findings, histochemical analyses revealed that B. cinerea infection caused nitric oxide (NO) accumulation in chloroplasts, which was not detected in plants treated with TRS 106, while treatment of plants with TRS 106 caused systemic spreading of H2O2 and NO accumulation in apoplast and nuclei. SPME-GCxGC TOF-MS analysis revealed 24 volatile organic compounds (VOC) released by tomato plants treated with TRS 106. Some of the hexanol derivatives, e.g., 4-ethyl-2-hexynal and 1,5-hexadien-3-ol, and salicylic acid derivatives, e.g., 4-hepten-2-yl and isoamyl salicylates, are considered in the protection of tomato plants against B. cinerea for the first time. The results are valuable for further studies aiming to further determine the location and function of NO in plants treated with Trichoderma and check the contribution of detected VOC in plant protection against B. cinerea
LED Light Quality Affected Bioactive Compounds, Antioxidant Potential, and Nutritional Value of Red and White Cabbage Microgreens
Microgreens are environmentally friendly and have health benefits in addition to their basic nutritional contents. The effect of white (W), white–blue (W + B), and white–red (W + R) light on the bioactive compounds, nutrient composition, and antioxidant potential of red and white cabbage microgreens were investigated using light-emitting diodes (LEDs). The results showed that protein, fat, ash, chlorophylls, and carotenoids were the highest in microgreens under W light, while phenolic compounds were highest in microgreens under W + B light. Supplementation with white light, as well as red or blue light, resulted in higher levels of sugars and total fiber in both white and red microgreens. Twenty-six and thirty-three phenolic compounds were identified in white and red cabbage microgreens, respectively. The identified phenolics belonged to three classes, including phenolic acids, flavonols, and anthocyanins. The antioxidant potential of both cabbage microgreens was determined by four methods (ABTS, DPPH, ORAC, and FRAP). It was found that the highest antioxidant potential was observed in microgreens grown under the W + B light combination. On the other hand, the W + R light combination increased the content of β-sitosterol and campesterol. The results may be helpful in the selection of the type of LED lighting that determines the high nutritional and health-promoting potential of white and red cabbage microgreens
Halloysite Nanotubes and Silane-Treated Alumina Trihydrate Hybrid Flame Retardant System for High-Performance Cable Insulation
The effect of the presence of halloysite nanotubes (HNTs) and silane-treated alumina trihydrate (ATH-sil) nanofillers on the mechanical, thermal, and flame retardancy properties of ethylene-vinyl acetate (EVA) copolymer/low-density polyethylene (LDPE) blends was investigated. Different weight percentages of HNT and ATH-sil nanoparticles, as well as the hybrid system of those nanofillers, were melt mixed with the polymer blend (reference sample) using a twin-screw extruder. The morphology of the nanoparticles and polymer compositions was studied using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The mechanical properties, hardness, water absorption, and melt flow index (MFI) of the compositions were assessed. The tensile strength increases as a function of the amount of HNT nanofiller; however, the elongation at break decreases. In the case of the hybrid system of nanofillers, the compositions showed superior mechanical properties. The thermal properties of the reference sample and those of the corresponding sample with nanofiller blends were studied using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Two peaks were observed in the melting and crystallization temperatures. This shows that the EVA/LDPE is an immiscible polymer blend. The thermal stability of the blends was improved by the presence of HNTs and ATH-sil nanoparticles. Thermal degradation temperatures were shifted to higher values by the presence of hybrid nanofillers. Finally, the flammability of the compositions was assessed. Flammability as reflected by the limiting oxygen index (OI) was increased by the presence of HNT and ATH-sil nanofiller and a hybrid system of the nanoparticles
Liver Antioxidant Capacity and Steatosis in Laying Hens Exposed to Various Quantities of Lupin (<i>Lupinus angustifolius</i>) Seeds in the Diet
Despite the many beneficial properties of legume plants, their use in diets for poultry is limited by the presence of antinutritional factors. The aim of the study was to determine the activity of DT-diaphorase, ethoxycoumarin O-deethylase, and catalase, and the concentration of malondialdehyde in liver tissue, as well as the activity of SOD and CAT in the serum of Hy-line Brown hens fed a diet supplemented with various doses of Lupinus angustifolius seeds. The results indicate that the use of large amounts of lupin in the diet resulted in an increase in MDA concentration in the liver and the lipid vacuolization of hepatocytes. A significant increase in DTD activity was observed in chickens receiving 15% lupin. Regardless of lupin dose, no increase in SOD activity was observed in chicken serum after 33 days of the experiment. From the 66th day of the experiment, an increase in catalase activity in the serum of laying hens was observed, while low activity of this enzyme was found in the liver. It can be concluded that the short-term use of lupin in the diet of laying hens does not affect the activity of antioxidant enzymes and, therefore, does not affect the oxidative–antioxidant balance of their body