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Open access

Vincenzo Alagna, Vincenzo Bagarello, Simone Di Prima, Fabio Guaitoli, Massimo Iovino, Saskia Keesstra and Artemi Cerdà

Abstract

In bare soils of semi-arid areas, surface crusting is a rather common phenomenon due to the impact of raindrops. Water infiltration measurements under ponding conditions are becoming largely applied techniques for an approximate characterization of crusted soils. In this study, the impact of crusting on soil hydraulic conductivity was assessed in a Mediterranean vineyard (western Sicily, Italy) under conventional tillage. The BEST (Beerkan Estimation of Soil Transfer parameters) algorithm was applied to the infiltration data to obtain the hydraulic conductivity of crusted and uncrusted soils. Soil hydraulic conductivity was found to vary during the year and also spatially (i.e., rows vs. inter-rows) due to crusting, tillage and vegetation cover. A 55 mm rainfall event resulted in a decrease of the saturated soil hydraulic conductivity, Ks, by a factor of 1.6 in the inter-row areas, due to the formation of a crusted layer at the surface. The same rainfall event did not determine a Ks reduction in the row areas (i.e., Ks decreased by a non-significant factor of 1.05) because the vegetation cover intercepted the raindrops and therefore prevented alteration of the soil surface. The developed ring insertion methodology on crusted soil, implying pre-moistening through the periphery of the sampled surface, together with the very small insertion depth of the ring (0.01 m), prevented visible fractures. Consequently, Beerkan tests carried out along and between the vine-rows and data analysis by the BEST algorithm allowed to assess crusting-dependent reductions in hydraulic conductivity with extemporaneous measurements alone. The reliability of the tested technique was also confirmed by the results of the numerical simulation of the infiltration process in a crusted soil. Testing the Beerkan infiltration run in other crusted soils and establishing comparisons with other experimental methodologies appear advisable to increase confidence on the reliability of the method that seems suitable for simple characterization of crusted soils.

Open access

Emilia Jaroszewska

Abstract

The industry which was a driving force of the economy and contributed to the population growth in many cities for decades became later the source of their problems. The crisis of the activity of old industrial cities creating the economic base (especially of the traditional industry), provoked by the deindustrialisation process and in post-socialist countries additionally by the “shock” of the economic transformation, caused long-lasting and unfavourable changes in many areas. It resulted in the present process of shrinkage of old industrial cities in demographic, economic, social aspects as well as spatial ones (Bontje 2004; Oswalt 2005; Turok, Mykhnenko 2007; Pallagst et al. 2009; Cunning-ham-Sabot et al. 2010; Bontje, Musterd 2012; Hospers 2012, 2014; Haase et al. 2013; Pallagst et al. 2014; Stryjakiewicz 2014; Runge et al. 2018). This process can take a different course in different socio-economic patterns depending on the geographical situation and the time of observation. However, it leads to unfavourable results in each place, first of all to a decrease in the number of inhabitants. The aim of the article is twofold: (1) the identification and analysis of the process of urban shrinkage of Wałbrzych city as well as (2) the examination of different regeneration strategies adopted to mitigate negative effects of urban shrinkage. It is particularly important to understand this process and results of the adopted strategies especially in the context of the future development of this city which according to demographic forecasts will be shrinking in the long run.

Open access

Barbara Maćkiewicz, Raúl Puente Asuero and Antonio Garrido Almonacid

Abstract

Increasing demand for urban agriculture (UA) can be perceived as a global phenomenon. In some parts of the world its main function is to feed the rapidly growing population while in others it is more associated with lifestyle and environmental issues. Undeniably, UA provides opportunities for sustainable city development. UA can support all pillars of sustainable development: ecological, economic, and social. However, depending on existing circumstances certain pillars may be influenced more than others. In this paper we concentrate on urban allotments in Andalusia and take Baeza as an example of a city with an interesting approach to urban gardening. We attempt to answer the question how urban allotments in Baeza affect the city’s sustainable development and what remains to be done to make this influence more effective. Our study showed that allotment gardens in Baeza endorsed all three pillars of sustainable city development. However, developing broader community relations on the city scale, revival of declining local grocery market and dissemination of environmental initiatives which allotment gardens may also promote and facilitate was missing.

Open access

Aiyared Iampan

Abstract

In this paper, we construct the fundamental theorem of UP-homomorphisms in UP-algebras. We also give an application of the theorem to the first, second, third and fourth UP-isomorphism theorems in UP-algebras.

Open access

Elena Patrascu, Violeta Melinte, Carmen Paraschiv-Ferariu and Codrut Sarafoleanu

Abstract

Salivary gland cancers are represented by a heterogeneous histologic group of tumors, with low incidence, which may appear both in major and minor salivary glands. This article presents a review of the difficulties which may be encountered in this pathology during the treatment. The diagnosis of salivary gland cancers is often delayed, due to the histopathologic and immunohistochemistry results given in different period of times. There can be several difficulties in following the oncologic pre-treatment protocols, in terms of imaging technique, as MRI, useful for disease staging.

The treatment of salivary gland cancers is complex, due to the local anatomy and their aggressive potential. Because of their decreased incidence, there are few data that investigate the treatment in the case of these diseases. The current therapy available for the patients with salivary gland cancers is represented by complete surgical resection. Several treatment difficulties in cancers of the salivary glands may come from the surgical limitations and the insufficient data for adjuvant and palliative treatment. Due to the limitations of the local health system, there is a heterogeneous distribution of the oncologic centers, lack of equipment, prolonged time to follow general protocols, despite the aspect of case-individualized therapy according to the guidelines. We must not forget the tumor behaviour and individual reactivity of different patients to the same treatment protocol.

Open access

Othman A. Al Hanbali, Haji Muhammad Shoaib Khan, Muhammad Sarfraz, Mosab Arafat, Shakeel Ijaz and Abdul Hameed

Abstract

Use of transdermal patches can evade many issues associated with oral drug delivery, such as first-pass hepatic metabolism, enzymatic digestion attack, drug hydrolysis and degradation in acidic media, drug fluctuations, and gastrointestinal irritation. This article reviews various transdermal patches available in the market, types, structural components, polymer role, and the required assessment tools. Although transdermal patches have medical applications for smoking cessation, pain relief, osteoporosis, contraception, motion sickness, angina pectoris, and cardiac disorders, advances in formulation development are ongoing to make transdermal patches capable of delivering more challenging drugs. Transdermal patches can be tailored and developed according to the physicochemical properties of active and inactive components, and applicability for long-term use. Therefore, a number of chemical approaches and physical techniques for transdermal patch development are under investigation.

Open access

Mohammed Albratty, Karam Ahmed El-Sharkawy and Hassan Ahmed Alhazmi

Abstract

In an attempt to produce heterocyclic compounds based on 1,3,4-oxadiazole derivatives with potential antiviral activity, synthesis of compound 1 [2-(5-thioxo-4,5-dihydro-1,3,4-oxadiazol-2-yl)acetonitrile] was performed through the reaction of cyanoacetic acid hydrazide with carbon disulfide in alcoholic potassium hydroxide. Compound 1 has an activating methylene group, so it was directed toward some specific reactions. Thus, aryldiazonium chlorides reacted with compound 1 affording hydrazono derivatives 2a-c. Also, aromatic aldehydes reacted with compound 1 to produce compounds 3a,b. Furthermore, cyclic ketones were subjected to the synthesis of fused thiophene derivatives 4a,b via reaction with compound 1 in the presence of elemental sulfur. In addition, 1,3,4-oxadiazole derivative 1, when reacted with isothiocyanates, salicylaldehyde or 1,3-dicarbonyl compounds, formed thiazole derivatives 5a,b, coumarin derivative 6 and alkenyl derivatives 7a,b resp. Compound 7b underwent cyclization to afford pyridine derivative 8. Arylhydrazono derivatives 9a,b were produced through the reaction of compound 7a with aryldiazonium chlorides. Products 9a,b underwent cyclization to produce pyridazine derivatives 10a,b. Finally, 1,3,4-oxadiazole derivative 1 was directed toward reaction with hydrazine derivatives, bromoacetophenone and ethylchloroacetate affording compounds 11a,b, 12 and 13, resp. Fused thiophene derivatives 14a,b were produced via reaction of compounds 4a,b with a mixture of malononitrile and ethylorthoformate. Antiviral activity of the synthesized products showed that 5-(4-amino-3-ethyl-2-thioxo-2,3-dihydrothiazol-5-yl)-1,3,4-oxadiazole-2(3H)-thione (5a) and 5-(4-amino-3-phenyl-2-thioxo-2,3-dihydrothiazol-5-yl)-1,3,4-oxadiazole-2(3H)-thione (5b) acted as the most active agents against Feline herpes virus, Feline corona virus, Herpes simplex virus-1 and Herpes simplex virus-2, whereas compound 2-(5-(2-phenylhydrazono)-4,5-dihydro-1,3,4-oxadiazol-2-yl)acetonitrile (11b) was the most effective against Vaccinia virus, Herpes simplex virus (TK-KOS-ACVr), Coxsackie virus B4 and Vesicular stomatitis virus.

Open access

Maja Beus, Diana Fontinha, Jana Held, Zrinka Rajić, Miguel Prudêncio and Branka Zorc

Abstract

The paper is focused on the synthesis and screening of the antiplasmodial activity of novel fumardiamides 5–10 with the mefloquine pharmacophore and a Michael acceptor motif. Multi-step reactions leading to the title compounds included two amide bond formations. The first amide bond was achieved by the reaction of (E)-ethyl 4-chloro-4-oxobut-2-enoate (1) and N 1-(2,8-bis(trifluoromethyl)quinolin-4-yl) butane-1,4-diamine (2). The obtained ester 3 was hydrolyzed and gave acid 4, which then reacted with the selected halogenanilines in the presence of HATU/DIEA and formed products 5–10. Title compounds showed marked, dose dependent activity in vitro against hepatic stages of Plasmodium berghei. IC 50 values of the most active compounds 5, 7 and 9 bearing 3-fluoro, 3-chloro and 3-trifluoromethyl substituents were 3.04–4.16 µmol L−1, respectively. On the other hand, the compounds exerted only weak activity against the erythrocytic stages of two P. falciparum strains (Pf3D7 and PfDd2) in vitro, with the exception of compound 5 (IC 50 = 2.9 µmol L−1).

Open access

Monika Śleziak and Marek Duliński

Abstract

The isotope activity concentration of rocks and bottom sediments was evaluated based on the samples collected from sedimentation ponds and gangue repositories. Radium 226Ra, thorium 228Th and potassium 40K activities were measured by gamma spectrometry using high-purity germanium detector – HPGe 4020. The radiation effect resulting from the presence of natural radionuclides was estimated by radiological hazard indices such as f 1 and f 2 coefficients, radium equivalent, internal and external hazard indices and absorbed dose rate. Performed measurements and calculations have shown that the bottom sediments are most contaminated. They may pose a serious radiological hazard for present and future generations.

Open access

Amir Ali, Muhammad Makshoof Athar, Mahmood Ahmed, Kashif Nadeem, Ghulam Murtaza, Umar Farooq and Muhammad Salman

Abstract

With the increased number of multi-drug formulations, there is a need to develop new methods for simultaneous determinations of drugs. A precise, accurate and reliable liquid chromatographic method was developed for simultaneous determination of paracetamol, thiamine, and pyridoxal phosphate in pharmaceutical formulations. Separation of analytes was carried out with an Agilent Poroshell C18 column. A mixture of ammonium phosphate buffer (pH = 3.0), acetonitrile and methanol in the ratio of 86:7:7 (V/V/V) was used as the mobile phase pumped at a flow rate of 1.8 mL min−1. Detection of all three components, impurities and degradation products was performed at the selected wavelength of 270 nm. The developed method was validated in terms of linearity, specificity, precision, accuracy, LOD and LOQ as per ICH guidelines. Linearity of the developed method was found in the range 17.5–30 µg mL−1 for thiamine, 35–60 µg mL−1 for pyridoxal phosphate and 87.5–150 µg mL−1 for paracetamol. The coefficient of determination was ≥ 0.9981 for all three analytes. The proposed HPLC method was found to be simple and reliable for the routine simultaneous analysis of paracetamol, thiamine and pyridoxal phosphate in tablet formulations. Complete separation of analytes in the presence of degradation products indicated selectivity of the method.