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Open access

Asiata Omotayo Ibrahim, Misbaudeen Abdul-Hammed, Samuel Adewale Adegboyega, Monsurat Olajide and Akeem Abefe Aliyu

Abstract

Tomato is a significant vegetable crop with numerous health benefits derived from its carotenoids, flavonoids and other phytonutrients contents. This work studies the nutritional qualities and carotenoids contents of five different cultivars of tomatoes (San Marz, Nasmata, Roma VF, Ogbomoso local and 4-lobes). The variations of pH, titratable acidity, reducing sugar, total solid, lycopene and beta-carotene contents of these tomatoes were investigated under ambient temperature and field ripening techniques and the mean values of these parameters investigated at different ripening stages and techniques were compared. Lycopene contents were significantly higher (p ˂ 0.05) in tomatoes subjected to field ripening compared with those ripened under ambient temperature. The highest lycopene content (17.18 μg/g) was observed in Roma VF cultivar at fully-ripe stage under field ripening technique while the lowest value (0.64 μg/g) was in 4-lobes cultivar at semi-ripe stage under ambient temperature ripening. Similar trend was observed in the variation of betacarotene (a pro-Vitamin A index) among the tomato cultivars. The evaluated reducing sugar contents (ranging from 1.84 to 5.23 μg/g) were significantly higher (p < 0.05) in fully-ripe tomatoes compared to semi-ripe ones under field ripening and the trend was reversed for some cultivars under ambient temperature ripening. The titratable acidities of the tomatoes were significantly higher at the semi-ripe stage (0.24 to 0.38 %) under field ripening than those obtained under ambient temperature ripening (0.15 to 0.25 %). The pH of the tomatoes ranged from 3.58 to 4.07 and 3.46 to 5.40 under field and ambient temperature ripening, respectively, and the higher pH values obtained under ambient temperature ripening condition could make such tomatoes unsuitable in tomato processing plants. Consumption of tomatoes for the purpose of dietary antioxidant lycopene and pro-Vitamin A could maximally be achieved at fully-ripe stage under field ripening condition.

Open access

Minodora Onisâi, Ana-Maria Vlădăreanu, Andreea Spînu, Mihaela Găman and Horia Bumbea

Abstract

Immune thrombocytopenia is an autoimmune hematological disorder characterized by severely decreased platelet count of peripheral cause: platelet destruction via antiplatelet antibodies which may also affect marrow megakaryocytes. Patients may present in critical situations, with cutaneous and/or mucous bleeding and possibly life-threatening organ hemorrhages (cerebral, digestive, etc.) Therefore, rapid diagnosis and therapeutic intervention are mandatory.

Corticotherapy represents the first treatment option, but as in any autoimmune disorder, there is a high risk of relapse. Second line therapy options include: intravenous immunoglobulins, thrombopoietin receptor agonists, rituximab or immunosuppression, but their benefit is usually temporary. Moreover, the disease generally affects young people who need repeated and prolonged treatment and hospitalization and therefore, it is preferred to choose a long term effect therapy. Splenectomy – removal of the site of platelet destruction – represents an effective and stable treatment, with 70-80% response rate and low complications incidence.

A challenging situation is the association of ITP with pregnancy, which further increases the risk due to the immunodeficiency of pregnancy, major dangers of bleeding, vital risks for mother and fetus, potential risks of medication, necessity of prompt intervention in the setting of specific obstetrical situations – delivery, pregnancy loss, obstetrical complications, etc.

We present an updated review of the current clinical and laboratory data, as well as a detailed analysis of the available therapeutic options with their benefits and risks, and also particular associations (pregnancy, relapsed and refractory disease, emergency treatment).

Open access

W.C. Shen, L.L. Lin, C.Y. Shen, S. Xing and Z.B. Pan

Abstract

TbxHo0.9−xNd0.1(Fe0.8Co0.2)1.93/epoxy (0 ⩽ x ⩽ 0.40) composites are fabricated in the presence of a magnetic field. The structural and dynamic magnetoelastic properties are investigated as a function of both magnetic bias field Hbias and frequency f at room temperature. The composites are formed as textured orientation structure of 1–3 type with 〈1 0 0〉 preferred orientation for x ⩽ 0.10 and 〈1 1 1〉-orientation for x ⩾ 0.25. The composites generally possess insignificant eddy-current losses for frequency up to 50 kHz, and their dynamic magnetoelastic properties depend greatly on Hbias. The elastic modulus (E3H and E3B) shows a maximum negative ΔE effect, along with a maximum d33, at a relatively low Hbias ~ 80 kA/m, contributed by the maximum motion of non-180° domain-wall. The 1–3 type composite for x ⩾ 0.25 shows an enhanced magnetoelastic effect in comparison with 0 to 3 type one, which can be principally ascribed to its easy magnetization direction (EMD) towards 〈1 1 1〉 axis and the formation of 〈1 1 1〉-texture-oriented structure in the composite. These attractive dynamic magnetoelastic properties, e.g., the low magnetic anisotropy and d33,max as high as 2.0 nm/A at a low Hbias ~ 80 kA/m, along with the light rare-earth Nd element existing in insulating polymer matrix, would make it a promising magnetostrictive material system.

Open access

Denis Sokol, Maksim Ivanov, Andrei N. Salak, Robertas Grigalaitis, Juras Banys and Aivaras Kareiva

Abstract

Magnesium-aluminum-bismuth layered double hydroxides (Mg3Al1−xBix; LDHs) were prepared using both coprecipitation and sol-gel methods. For the preparation of Mg/Al/Bi LDH by the co-precipitation method, the appropriate amounts of dissolved starting materials (Al(NO3)3 · 9H2O, Mg(NO3)2 · 6H2O and Bi(NO3)3 · 5H2O) were mixed with a solution of NaHCO3:NaOH. In the sol-gel processing, the precursor Mg–Al–Bi–O gels were synthesized using the same starting materials and ethylene glycol as complexing agent. The mixed-metal oxides obtained by subsequent heating of Mg–Al–Bi–O gels at 650 °C were reconstructed to Mg3Al1−xBix LDHs in water at 80 °C. All the synthesized products were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and dielectric measurements.

Open access

Rafał Mazur, Sebastian Masternak, Michał Pająk, Nikodem Skoczeń, Ewelina Soroka and Marcin Olajossy

Abstract

Introduction: Smoking is a huge medical and social problem in Poland, with as many as about 24% of Poles being addicted to nicotine. Approximately 6 million people worldwide die every year from conditions that are closely related to tobacco addiction, such as cancer and cardiovascular, metabolic or lung diseases. The difficulty in combatting nicotine dependence is largely due to the complex mechanism of this addiction. The motivation of a patient to quit smoking is of great importance in the difficult withdrawal process. Strengthening this motivation is one of the most important tasks of physicians and addiction therapists.

Overview of literature: Nicotine replacement therapy (NRT) has been the most widely known way to break away from smoking addiction for many years now. It involves delivering nicotine to the body in ways that are less harmful than through tobacco smoke. As a consequence, the cravings for nicotine are reduced, making it easier for the patient to break with the addiction. Clinical trials have shown that the use of NRT is associated with a 50-70% increased chance of maintaining abstinence from smoking compared to placebo. There are many NRT products, including nicotine chewing gum, nicotine patches, lozenges, dissolvable nicotine sticks, or inhalers. Bupropion is a selective dopamine–noradrenaline reuptake inhibitor. This drug is one of the most commonly used in the pharmacotherapy of depression in the United States. At the same time, it has been found to have a positive effect on people trying to break up with the habit of smoking cigarettes. The mechanism of action remains unknown in this case, but studies clearly indicate the efficacy of bupropion, which is comparable to the efficacy of NRT. Varenicline is a partial agonist selective for α4β2 nicotinic acetylcholine receptors. It has a higher affinity for these receptors than nicotine. By stimulating them, it causes an increase in dopamine secretion (but to a lesser extent than cigarette smoking), helping in this way ease withdrawal symptoms.

Conclusions: Varenicline has higher efficacy than bupropion and NRTs. Simultaneous use of two NRT forms increases the effectiveness of this method to a level comparable to varenicline. Contrary to previous reports, it seems that varenicline does not increase self-aggressive behaviour and the risk of suicide. The effectiveness of antinicotinic drugs depends on the sex of the patient. For both sexes, the most effective drug is varenicline. It is slightly more effective in women than in men. By contrast, NRT and bupropion show greater therapeutic potential in men.

Open access

Mohammad Abu Haija, Georgia Basina, Fawzi Banat and Ahmad I. Ayesh

Abstract

Spinel ferrite nanoparticles in the form CuFe2O4 were tested for gas sensing applications. Nanoparticles pressed in a disk form were used to construct conductometric gas sensors. The disk was placed between two electrical electrodes wherein the top electrode had a grid structure. The produced sensors were tested against H2S and H2 gases and they were found to be selective and sensitive to H2S concentration as low as 25 ppm. The composition of the nanoparticles was confirmed by X-ray diffraction and energy dispersive X-ray spectroscopy measurements. The crystal structure was verified by both X-ray diffraction and transmission electron microscope. The observations obtained from the experiments demonstrated the high potential of using CuFe2O4 nanoparticles for H2S sensing applications.

Open access

Darja Kanduc

Abstract

This study investigates the hypothesis that cross-reactions may occur between human cardiac proteins and influenza antigens, thus possibly representing the molecular mechanism underlying influenzaassociated sudden unexpected death (SUD). Using titin protein as a research model, data were obtained on (1) the occurrence of the titin octapeptide AELLVLLE or its mimic AELLVALE in influenza A virus hemagglutinin (HA) sequences; (2) the immunological potential of AELLVLLE and its mimic AELLVALE; (3) the possible role of the flanking amino acid aa) context of the two octapeptide determinants in eliciting cross-reactivity between the human cardiac titin protein and HA antigens.

Open access

Eva Maria Prem, Nadine Praeg, Katrin Hofmann, Andreas Otto Wagner and Paul Illmer

Summary

Five differently developed soils aged 6, 35, 80, 150, and >5000 years with the same bedrock and the same (current) climate conditions were chosen to assess abiotic and enzymatic properties as well as methanogenic and methanotrophic activities. Most abiotic properties (dry weight, pH, soil organic matter, and ammonium content), enzyme activities (dehydrogenase [DH] activity, ammonification [AM] rate, dimethylsulfoxide reduction), and potential methane oxidation (PoMO) per gram of dry weight (DW) increased with soil age. In contrast, potential methane production (PoMP) as well as the nitrate content per gram of DW and most enzymatic properties per gram of soil organic matter (SOM) did not increase with soil age but reached its maximum in the middle-aged soils (80–150 years). Our results show that (i) microbial activity does not consequently increase with SOM content/soil age; (ii) methane production can be measured in undeveloped soils, whereas methane oxidation is more restricted to fully developed soils; and (iii) certain soil modifications (change in water content, ammonium addition) could influence potential methane production/oxidation. When considering the concurrent release of raw soil because of the melting of perpetual ice, these data could help to better understand and assess the consequences of global change.

Open access

Anna Lenart-Boroń, Tadeusz Zając, Piotr Mateusz Boroń and Agnieszka Klimek-Kopyra

Summary

The bacterial nodulation (nod) genes are essential in the formation process of root nodules. This study was aimed to verify the occurrence of nodule-associated bacteria in two pea varieties (“Tarchalska” and “Klif ”) inoculated with Rhizobium inoculants – Nitragine™ and a noncommercial one produced by the Polish Institute of Soil Science and Plant Cultivation (IUNG). The number of colonies isolated on yeast extract mannitol (YEM) agar from the nodules of “Klif ” inoculated with IUNG inoculants was significantly higher than the number of colonies isolated from other variants. Species identification was based on sequencing of 16S rDNA, which revealed that despite careful sterilization of nodules, sequences of other bacterial species were detected. Among them, one sequence belonged to Rhizobium leguminosarum (isolated from IUNG inoculant). To assess the presence of nodulation-capable Rhizobium, amplification of the nodC gene was performed, which revealed that of 29 samples, 19 were positive. The remaining isolates, including reference strain and bacteria isolated from Nitragine™, lacked this gene. The results show that pea nodules harbor a very diverse community of bacteria. The lack of nodC gene in some strains isolated from plants inoculated with Nitragine™ and with IUNG inoculant proves that even if R. leguminosarum are abundant, they may not be efficient in nodulation.

Open access

Giovanni Peratoner and Erich M. Pötsch

Summary

In terms of botanical composition, grassland vegetation in experimental plots and field studies can be described by means of different parameters (plant density, cover, frequency or yield proportion). Each parameter describes different features, which under certain circumstances may be correlated one to each other to some extent, but are not fully equivalent. The choice of the parameter to be assessed depends therefore, in first instance, on the specific aim of the investigation. For the assessment of the chosen parameter, many methods are available that differ from each other in terms of subjectivity, precision, effort and requirement for technical equipment. The choice of method depends mainly on the required precision, the affordable effort and on the available resources.