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991.
Jee-Hoon Kim Anna Jażdżewska Han-Gu Choi Won Kim 《Oceanological and hydrobiological studies.》2014,43(1):106-113
This is a first account on amphipods from Marian Cove in Maxwell Bay, near the King Sejong Station, King George Island, the Antarctic. We have conducted a survey in 14 localities in the shallow sublittoral zone. A total of 22 amphipod species belonging to 12 families were identified. Six of these species were new for the whole Maxwell Bay. Our findings increase the amphipod fauna of Maxwell Bay from 55 to 61 species. The dominant species in the shallow sublittoral zone of Marian Cove were: Cheirimedon femoratus and Gondogeneia antarctica, followed by Bovallia gigantea, Orchomenella cf. ultima, Paradexamine fissicauda, Prostebbingia brevicornis, Pariphimedia integricauda, and Jassa wandeli. 相似文献
992.
The concept of recovery has been an influence on addicted individuals for many decades. But only in the past 15 years has the concept had a purchase in the world of public policy. In the USA, federal and state officials have promulgated policies intended to foster ‘recovery‐oriented systems of care’ and have ratified recovery‐supportive laws and regulations. Though of more recent vintage and therefore less developed, recovery policy initiatives are also being implemented in the UK. The present paper describes recovery‐oriented policy in both countries and highlights key evaluations of the recovery‐oriented interventions. [Humphreys K, Lembke A. Recovery‐oriented policy and care systems in the UK and USA. Drug Alcohol Rev 2014;33:13–18] 相似文献
993.
In 2011, the Australian National Health and Medical Research Council (NHMRC) initiated an inquiry to determine whether there is a need for expanded ethical guidance in the form of a discrete guidance document for alcohol and other drug (AOD) research. An issues paper was developed to frame the inquiry. AOD researchers, Human Research Ethics Committees and others were invited to discuss whether there are distinctive ethical issues facing researchers and Human Research Ethics Committees in the AOD setting. Based on the public submissions, the NHMRC recommended that no AOD research‐specific guidance is required. The inquiry and the NHMRC decision were not widely publicized, and we feel there is a need for further discussion. In order to do so, we have analysed the public inquiry submissions and described the central themes. Few submissions in the inquiry explicitly agreed AOD research warrants a specific guidance framework. Most were concerned that the NHMRC issues paper unfairly targeted people who use drugs as complex research participants. The inquiry highlights tensions around research governance and ethics review boards dealing with illicit and stigmatised behaviours. While we agree that a specific guidance framework for AOD research is not needed and could potentially be harmful and restrictive, we are concerned that the wholesale rejection of a guidance framework has closed the door to much needed debate. There remains, we argue, a need for alternative strategies and tools to support ethical research, inform and streamline institutional ethics approval, and engage and protect participants. [Olsen A, Mooney‐Somers J. Is there a problem with the status quo? Debating the need for standalone ethical guidelines for research with people who use AODs. Drug Alcohol Rev 2014;33:637‐642] 相似文献
994.
Agnieszka Sobczak-Kupiec Anna Drabczyk Wioletta Florkiewicz Magdalena Gb Sonia Kudacik-Kramarczyk Dagmara Sota Agnieszka Tomala Boena Tyliszczak 《Materials》2021,14(9)
Regenerative medicine is becoming a rapidly evolving technique in today’s biomedical progress scenario. Scientists around the world suggest the use of naturally synthesized biomaterials to repair and heal damaged cells. Hydroxyapatite (HAp) has the potential to replace drugs in biomedical engineering and regenerative drugs. HAp is easily biodegradable, biocompatible, and correlated with macromolecules, which facilitates their incorporation into inorganic materials. This review article provides extensive knowledge on HAp and collagen-containing compositions modified with drugs, bioactive components, metals, and selected nanoparticles. Such compositions consisting of HAp and collagen modified with various additives are used in a variety of biomedical applications such as bone tissue engineering, vascular transplantation, cartilage, and other implantable biomedical devices. 相似文献
995.
During the steel production process, nearly twice as many input materials are used as compared to finished products. This creates a large amount of post-production waste, including slag, dust, and sludge. New iron production technologies enable the reuse and recycling of metallurgical waste. This paper presents an investigation on the reduction of selected iron-bearing waste materials in a laboratory rotary furnace. Iron-bearing waste materials in the form of dust, scale, and sludge were obtained from several Polish metallurgical plants as research material. A chemical analysis made it possible to select samples with sufficiently high iron content for testing. The assumed iron content limit in waste materials was 40 wt.% Fe. A sieve analysis of the samples used in the subsequent stages of the research was also performed. The tests carried out with the use of a CO as a reducer, at a temperature of 1000 °C, allowed to obtain high levels of metallization of the samples for scale 91.6%, dust 66.9%, and sludge 97.3%. These results indicate that in the case of sludge and scale, the degree of metallization meets the requirements for charge materials used in both blast furnace (BF) and electric arc furnace (EAF) steelmaking processes, while in the case of reduced dust, this material can be used as enriched charge in the blast furnace process. Reduction studies were also carried out using a gas mixture of CO and H2 (50 vol.% CO + 50 vol.% H2). The introduction of hydrogen as a reducing agent in reduction processes meets the urgent need of reducing CO2 emissions. The obtained results confirm the great importance and influence of the selection of the right amount of reducer on the achievement of a high degree of metallization and that these materials can be a valuable source of metallic charge for blast furnace and steelmaking processes. At an earlier stage of the established research program, experiments of the iron oxides reduction from iron-bearing waste materials in a stationary layer in a Tammann furnace were also conducted. 相似文献
996.
Marek Molenda Jzef Horabik Piotr Parafiniuk Anna Oniszczuk Maciej Bada Justyna Wajs Ewa Gondek Marcin Chutkowski Aleksander Lisowski Joanna Wicek Mateusz Stasiak 《Materials》2021,14(11)
The objective of the reported project was to produce wood agglomerates from popular East European species to determine their strength and combustion properties. Closed-die pellets were produced from sawdust of six types of wood common on the East European market: pine, willow, oak, poplar, birch, and beech. The properties of pellets, determined by the type of wood, were influenced by the compaction pressure and the moisture content of the sawdust. The highest average pellet density was obtained for oak sawdust, while the lowest density was obtained for poplar pellets. Expansion of pellets after removing from the die was found to be dependent on the wood species, and as expected, on compaction pressure. The pellet expansion increased after 2 h of conditioning in the laboratory and with an increase in moisture content. The highest and the smallest strength were obtained for oak pellets and for birch sawdust, respectively. The strength of the pellets increased by more than 100% with an increase in the compaction pressure from 60 MPa to 120 MPa. The average strength decreased by 65% with increasing moisture content. For all tested materials, drop resistance remained at a high level, acceptable in industrial practice. The highest calorific value of 18.97 MJ/kg was obtained for pine pellets. The highest ash value of 1.52% was obtained for willow pellets and the lowest value of 0.32% for pine pellets. 相似文献
997.
Novel hybrid materials based on the poly(methyl methacrylate) (PMMA) matrix and lanthanide(III) carboxylates Eu:2,6-DClB and Tb:2,6-DClB were synthesized and carefully analyzed in the context of their potential application in optically active polymer-based optical fibers. To determine the usefulness of the obtained materials, a careful thermal, mass spectroscopy, and optical characterization was performed, focusing on the features critical for the technology of optical fiber processing. In addition, the luminescent features of both lanthanide complexes and the resulting hybrid composites were carefully investigated to identify the processes responsible for light emission and to analyze the influence of the PMMA host on light emission intensity and spectral characteristics. The obtained results showed that both lanthanide carboxylate complexes exhibited intense luminescence in the red and green spectral range, typical of europium and terbium dopants, and that those features were well preserved after introducing them into the PMMA polymer. Thermal analysis also proved that introducing the luminescent additives did not significantly affect the thermal properties of both hybrid materials, thus enabling further processing into the form of optical fibers. 相似文献
998.
Graphene oxide (GO) was proposed as an efficient carrier of antibiotics. The model drug, amoxicillin (AMOX), was attached to GO using a peptide linker (Leu-Leu-Gly). GO-AMOX was dispersed in a hydrogel to which the enzyme responsible for releasing AMOX from GO was also added. The drug molecules were released by enzymatic hydrolysis of the peptide bond in the linker. As the selected enzyme, bromelain, a plant enzyme, was used. The antibacterial nature of the carrier was determined by its ability to inhibit the growth of the Enterococcus faecalis strain, which is one of the bacterial species responsible for periodontal and root canal diseases. The prepared carrier contained only biocompatible substances, and the confirmation of its lack of cytotoxicity was verified based on the mouse fibrosarcoma cell line WEHI 164. The proposed type of preparation, as a universal carrier of many different antibiotic molecules, can be considered as a suitable solution in the treatment of inflammation in dentistry. 相似文献
999.
Within the broad group of Fe non-heme oxidases, our attention was focused on the catechol 1,2- and 2,3-dioxygenases, which catalyze the oxidative cleavage of aromatic rings. A large group of Fe complexes with N/O ligands, ranging from N3 to N2O2S, was developed to mimic the activity of these enzymes. The Fe complexes discussed in this work can mimic the intradiol/extradiol catechol dioxygenase reaction mechanism. Electronic effects of the substituents in the ligand affect the Lewis acidity of the Fe center, increasing the ability to activate dioxygen and enhancing the catalytic activity of the discussed biomimetic complexes. The ligand architecture, the geometric isomers of the complexes, and the substituent steric effects significantly affect the ability to bind the substrate in a monodentate and bidentate manner. The substrate binding mode determines the preferred mechanism and, consequently, the main conversion products. The preferred mechanism of action can also be affected by the solvents and their ability to form the stable complexes with the Fe center. The electrostatic interactions of micellar media, similar to SDS, also control the intradiol/extradiol mechanisms of the catechol conversion by discussed biomimetics. 相似文献
1000.
Mohamad Kahar Ab Wahab Halimatul Syahirah Mohamad Elammaran Jayamani Hanafi Ismail Izabela Wnuk Anna Przyby Tomasz Stachowiak Przemysaw Postawa 《Materials》2021,14(11)
The preparation of polystyrene/thermoplastic starch (PS/TPS) blends was divided into three stages. The first stage involved the preparation of TPS from sago starch. Then, for the second stage, PS was blended with TPS to produce a TPS/PS blend. The ratios of the TPS/PS blend were 20:80, 40:60, 60:40, and 80:20. The final stage was a modification of the composition of TPS/PS blends with succinic anhydride and ascorbic acid treatment. Both untreated and treated blends were characterized by their physical, thermal, and surface morphology properties. The obtained results indicate that modified blends have better tensile strength as the adhesion between TPS and PS was improved. This can be observed from SEM micrographs, as modified blends with succinic anhydride and ascorbic acid had smaller TPS dispersion in PS/TPS blends. The micrograph showed that there was no agglomeration and void formation in the TPS/PS blending process. Furthermore, modified blends show better thermal stability, as proved by thermogravimetric analysis. Water uptake into the TPS/PS blends also decreased after the modifications, and the structural analysis showed the formation of a new peak after the modification process. 相似文献