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Kuru, D, Aktitiz, S, Atakan, MM, Köse, MG, Turnagöl, HH, and Koşar, ŞN. Effect of pre-exercise sodium citrate ingestion on repeated sprint performance in soccer players. J Strength Cond Res38(3): 556–562, 2024—This study aimed to test the hypothesis that sodium citrate (CIT) administered 180 minutes before exercise improves repeated sprint performance in athletes within a field-based setting. Twenty male soccer players (mean ± SD: age = 20.9 ± 2.3 years; body mass [BM] = 73.8 ± 5.9 kg) performed a running-based anaerobic sprint test (RAST) with 0.5 g·kg−1BM of CIT or with placebo (PLC; NaCl) ingestion 180 minutes before exercise in a randomized, crossover, and double-blind design, with at least 6 days between the trials. Blood samples were collected before exercise and at first, third, fifth, and seventh minutes after exercise to analyze blood pH, bicarbonate, and lactate levels. Gastrointestinal symptoms were also monitored at 30-minute intervals for 180 minutes after CIT and PLC ingestion. Pre-exercise blood pH (CIT = 7.49 ± 0.03 vs. PLC = 7.41 ± 0.02) and bicarbonate (CIT = 30.57 ± 1.33 vs. PLC = 25.25 ± 1.52) increased with CIT compared with PLC (p< 0.001). Blood pH, bicarbonate, and lactate at the first, third, fifth, and seventh minutes after RAST with CIT were higher than PLC (p< 0.05), except for lactate at first minute (p> 0.05). Compared with PLC, CIT ingestion significantly improved minimum power output (p= 0.024) and percentage decrement score (p= 0.023). Gastrointestinal symptoms were significantly higher after CIT ingestion vs. PLC at 30th (p= 0.003) and 60th minutes (p= 0.010). However, there were no significant differences at 90th, 120th, 150th, or 180th minutes (p> 0.05). The ingestion of 0.5 g·kg−1BM of CIT 180 minutes before exercise is an effective ergogenic aid for improving repeated sprint ability as evidenced by improvements in minimum power output and percentage decrement score.

Conventional 2-pole AC machine windings have long end windings and generate harmonics, which increase losses and reduce torque density. This study investigates the performance tradeoff between the level of distortion (THD) in winding magneto-motive force (MMF) and end turn length on a 2-pole line start Synchronous Reluctance Machine (LS-SynRM) machine. A two-stage approach is used, winding and geometry optimization. Various multilayer winding configurations having unevenly distributed number of turns are investigated. First, the percentage of the turns in a coil group is optimized for minimum harmonics and end turn length for all structures. Second, geometric optimization is performed on selected winding configurations. Sixteen different configurations are optimized, and Pareto optimal solutions are obtained. Later, these solutions are graded with a new score-based assessment method to quantify the quality of the results. It is concluded that the designs having lower THD in winding MMF perform better than the designs with shorter end turns in terms of efficiency and torque density.

ObjectiveTo investigate the effects of high-intensity interval training (HIIT) and sprint interval training (SIT) on fat oxidation during exercise (FatOx) and how they compare with the effects of moderate-intensity continuous training (MICT).DesignSystematic review and meta-analysis.Data sourcesAcademic Search Ultimate, CINAHL, Networked Digital Library of Theses and Dissertations, Open Access Theses and Dissertations, OpenDissertations, PubMed/MEDLINE, Scopus, SPORTDiscus and Web of Science.Eligibility criteria for selecting studiesStudies using a between-group design, involving adult participants who were not trained athletes, and evaluating effects of HIIT or SIT on FatOx (vs no exercise or MICT) were included.ResultsEighteen studies of fair-to-good quality were included; nine comparing HIIT or SIT with no exercise and eleven comparing HIIT or SIT with MICT. A significant pooled effect of these types of interval training on FatOx was found (mean difference in g/min (MD)=0.08; 95% confidence interval (CI) 0.04 to 0.12; p<0.001). Significant effects were found for exercise regimens lasting ≥4 weeks, and they increased with every additional week of training (β=0.01; 95% CI 0.00 to 0.02; p=0.003). HIIT and/or SIT were slightly more effective than MICT (MD=0.03; 95% CI 0.01 to 0.05; p=0.005). The effects on FatOx were larger among individuals with overweight/obesity.ConclusionEngaging in HIIT or SIT can improve FatOx, with larger effects expected for longer training regimens and individuals with overweight/obesity. While some effects seem small, they may be important in holistic approaches to enhance metabolic health and manage obesity.

Exit-site infections (ESIs) increase the risk of developing peritoneal dialysis (PD) peritonitis and PD technique failure. There are no clear guidelines on how to monitor exit site (ES) after ESI with Staphylococcus aureusor Pseudomonas. We report on a 1-year observational study of 23 patients who developed an ESI with one of these serious pathogens. After completing initial antibiotic treatment, swabs were taken every month for 3 months. Primary treatment cure occurred in 19/23 (83%). Colonization of ES after primary cure occurred in 8/19 (42%) patients. In the eight colonized patients, five had subsequent PD technique failure due to infections. By contrast, during an average follow-up period of 7.2 months, none of the 11 patients who were proven noncolonized developed PD technique failure from infections; HR (colonized vs. noncolonized) = 10.89, 95% CI 2.6–45.43, p< 0.05. In conclusion, colonization significantly increased the risk of catheter loss. Increased surveillance and aggressive treatment may ameliorate this risk.

•This is the first study showing that 6 high-intensity interval training (HIIT) sessions over just 5 days is just as effective in increasing maximal oxygen uptake and endurance capacity and is more effective at improving submaximal exercise fat oxidation than 6 HIIT sessions over 2 weeks.•Five days of HIIT that lasts 60 min in total may be a potent stimulus to improve exercise performance and substrate oxidation.•Our findings reveal that this protocol achieves the fastest adaptation in response to a HIIT regime.•This study represents an important conceptual advance in demonstrating the remarkable ability of the human body to adapt to exercise stress in less than 2 weeks.

Background: Commercial poultry farming is expanding every day and contributing to the provision of affordable and high-quality protein. However, this sector is confronted with many diseases of which coccidiosis is among the most important. There are many registered patents affirming the health benefits of Garcinia kola in poultry. Objective: Evaluation of in vitro anticoccidial activities of the extracts and fractions of Garcinia kola against Eimeria tenella oocyst was carried out. Methods: Fresh seeds of G. kola were collected, dried under shade at room temperature, and pulverized using a mortar and a pestle. The powder was exhaustively extracted with a soxhlet apparatus using 70% methanol, and the crude methanol extract (CME) was concentrated to dryness using a rotary evaporator. The CME was further partitioned using butanol, ethylacetate, and n-hexane. The CME, butanol fraction (BTF), ethylacetate fraction (EAF), and hexane fraction (HXF) were concentrated in vacuo and tested for the presence of phytochemical constituents using standard procedures. Similarly, the CME, butanol, ethyl acetate, and hexane fractions were evaluated in vitro for oocyst sporulation inhibition. Results: Phytochemical analysis revealed the presence of cardiac glycosides, saponins, carbohydrates, steroids/triterpenes, tannins, flavonoids, and alkaloids in the CME and BTF. The EAF contains all the metabolites mentioned except saponins. Similarly, HXF contains only cardiac glycosides, tannins, and steroids/ triterpenes. The CME and BTF caused a concentration-dependent increase in the inhibition of sporulation of unsporulated oocysts of E. tenella. In the acute toxicity studies, the CME did not produce any toxic effect or mortality at doses between 10 and 5000 mg/kg. The CME was then considered safe, and the LD50 was assumed to be >5000 mg/kg. Conclusion: The data obtained in this study suggested that the crude methanol extract (CME) of G. kola could be an appreciable beneficial effect as an anticoccidial agent against Eimeria tenella oocyst.

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A 60-year-old patient with a history of diabetes mellitus and coronary artery disease was admitted to the eye nose and throat clinic due to complaints of difficulty in breathing. The patient was decided for functional endoscopic sinus surgery with the diagnosis of right nasal polyposis and chronic sinusitis. The patient had right visual loss with the findings of retinal artery occlusion, which is a rare ocular complication seen after functional endoscopic sinus surgery. Although the patient had proper urgent surgical and medical treatment, we did not observe visual improvement. Since this is a very rare condition, we intended to report it in the literature.

Objective:The purpose of this paper is to assess the clinical effectiveness of percutaneous laser disc decompression (PLDD) for patients with radicular pain due to intervertebral disc hernia and to describe our experience in this field in Bangladesh.

There is limited evidence that the tissue-protective effects of erythropoietin are mediated by a heterocomplex of the erythropoietin receptor and the β-common receptor (‘tissue-protective receptor’), which is pharmacologically distinct from the ‘classical’ erythropoietin receptor homodimer that is responsible for erythropoiesis. However, the role of the β-common receptor and/or erythropoietin in sepsis-induced cardiac dysfunction (a well known, serious complication of sepsis) is unknown. Here we report for the first time that the β-common receptor is essential for the improvements in the impaired systolic contractility afforded by erythropoietin in experimental sepsis. Cardiac function was assessed in vivo (echocardiography) and ex vivo (Langendorff-perfused heart) in wild-type and β-common receptor knockout mice, that were subjected to lipopolysaccharide (9 mg/kg body weight; young mice) for 16–18 hours or cecal ligation and puncture (aged mice) for 24 hours. Mice received erythropoietin (1000 IU/kg body weight) 1 hour after lipopolysaccharide or cecal ligation and puncture. Erythropoietin reduced the impaired systolic contractility (in vivo and ex vivo) caused by endotoxemia or sepsis in young as well as old wild-type mice in a β-common-receptor-dependent fashion. Activation by erythropoietin of the β-common receptor also resulted in the activation of well-known survival pathways (Akt and endothelial nitric oxide synthase) and inhibition of pro-inflammatory pathways (glycogen synthase kinase-3β, nuclear factor-κB and interleukin-1β). All the above pleiotropic effects of erythropoietin were lost in β-common receptor knockout mice. Erythropoietin attenuates the impaired systolic contractility associated with sepsis by activation of the β-common receptor, which, in turn, results in activation of survival pathways and inhibition of inflammation.

We have prepared and characterized a new set of highly fluorescent gold nanoclusters (AuNCs) using one-step aqueous reduction of a gold precursor in the presence of bidentate ligands made of lipoic acid anchoring groups, appended with either a poly(ethylene glycol) short chain or a zwitterion group. The AuNCs fluoresce in the red to near-infrared region of the optical spectrum with emission centered at ∼750 nm and a quantum yield of ∼10–14%, and they exhibit long fluorescence lifetimes (up to ∼300 ns). Dispersions of these AuNCs exhibit great long-term colloidal stability, over a wide range of pHs (2–13) and in the presence of high electrolyte concentrations, and a strong resistance to reducing agents such as glutathione. The growth strategy further permitted the controlled, in situfunctionalization of the NCs with reactive groups (e.g., carboxylic acid or amine), making these nanoclusters compatible with common and simple-to-implement coupling strategies, such as carbodiimide chemistry. These properties combined make these fluorescent NCs greatly promising for use in various imaging and sensing applications where NIR and long-lived excitations are desired.

Fluorescence resonance energy transfer between the metal core and the ligand in Au 25SG 18(SG-glutathione thiolate) is demonstrated using dansyl chromophores attached to the cluster core through glutathione linkers. The dansyl chromophore functionalization of the cluster has been carried out by two different routes. Efficient energy transfer from the dansyl donor to the Au 25core is manifested by way of the reduced lifetime of the excited state of the former and drastic quenching of its fluorescence. The donor−acceptor separation observed in the two synthetic routes reflects the asymmetry in the ligand binding on the cluster core, which is in agreement with the recent theoretical and experimental results on the structure of Au 25.

Ligand exchange offers an effective way to modify the properties of the recently prepared quantum clusters of gold. To tune optical and photoluminescence properties of one of the most stable quantum clusters of gold, Au 25SG 18(SG-glutathione thiolate), we functionalized it by the exchange of −SG with functionalized -SG and with an altogether different ligand, namely, 3-mercapto-2-butanol (MB). The products were characterized by various techniques such as optical absorption (UV−vis), Fourier-transform infrared (FT-IR), nuclear magnetic resonance (NMR), X-ray photoelectron (XPS), and luminescence spectroscopies, mass spectrometry, and thermogravimetry (TG). Analyses of the TG data helped to establish the molecular composition of the products. Ligand exchange reaction was monitored by NMR spectroscopy, and it was found that the exchange reaction follows a first order kinetics. The XPS study showed that after the exchange reaction there was no change in the chemical nature of the metal core and binding energy values of Au 4f 7/2and 4f 5/2, which are similar in both the parent and the exchanged products. Photoluminescence studies of these clusters, done in the aerated conditions, showed that the excitation spectrum of the MB-exchanged product is entirely different from the acetyl- and formyl-glutathione exchanged products. The inherent fluorescence and solid-state emission of these clusters were observed. This intense emission allows optical imaging of the material in the solid state. The emission is strongly temperature dependent. The synthesis of a diverse variety of clusters and their chemical stability and intense luminescence offer numerous applications in areas such as energy transfer, sensors, biolabeling, and drug delivery.

Nano-dispersed ZrO2/CoSb3 composites of various composition were prepared by uniaxial hot pressing of nano-sized powders of thermoelectric CoSb3 intermixed with ceramic nano-powders. The phase purity, the microstructure, and the temperature dependent transport parameters of the composites were investigated. Non-dispersed samples from nano-sized CoSb3 powders show higher electrical conductivity compared to melt-grown material which is attributed to the presence of a small excess of metallic Sb, but they exhibit lower thermal conductivity due to the fine-grained structure. Addition of 5 at.-% ZrO2 enhances the ratio of electrical to thermal conductivity, whereas hardly affects the Seebeck coefficient. In this manner the nano-dispersion method provides an effective approach to improving the material´s thermoelectric performance.

In this paper, the positive effect of a gold layer on cell viability is demonstrated by examining the results given by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfop henyl)-2H-tetrazolium (MTS) assay and two-color cell fluorescence viability (TCCV) assay. These cytotoxicity tests were performed with human cervical adenocarcinoma cells (HeLa cell line) and transformed African green monkey kidney fibroblast cells (Cos-7 cell line). To fabricate the nanostructures as drug vehicles, first, poly(l,l-lactide-co-ethylene glycol) (PLLA-PEG) and poly(N-isopropylacrylamide-co-d,d-lactide) (PNIPAAm-PDLA) were synthesized, and then two kinds of thermosensitive nanospheres comprising “shell-in-shell” structures without a gold layer (PLLA-PEG@PNIPAAm-PDLA) and with a gold layer (Au@PLLA-PEG@PNIPAAm-PDLA) were constructed by a modified double-emulsion method (MDEM). Both of them displayed a unique thermosensitive character exhibiting the lower critical solubility temperature (LCST) at 36.7 °C which was confirmed by UV−vis spectroscopy and differential scanning calorimetry (DSC). The release profiles of entrapped bovine serum albumin (BSA) were monitored at 22 and 37 °C, respectively, to reveal the thermal dependence on the release rate. In cell viability tests, both PLLA-PEG@PNIPAAm-PDLA and Au@PLLA-PEG@PNIPAAm-PDLA showed excellent cell viability, and furthermore, Au@PLLA-PEG@PNIPAAm-PDLA, particularly at high doses, exhibited more enhanced cell viability than PLLA-PEG@PNIPAAm-PDLA. This effect is mainly attributed to the gold layer which binds the protein molecules first and consequently facilitates transmembrane uptake of essential nutrients in the cell media, resulting in favorable cell proliferation.

Anodized alumina membranes (AAMs) were synthesized by a three-step electrochemical anodization of aluminum. The anodization results in a hexagonally pseudo-ordered 2D array of nanochannels. The AAMs were used as templates to grow Ni, Co, and Fe nanowires, with diameters in the range of 250−300 nm, by electrodeposition. The AAM appears to be amorphous, while the metal nanowires are polycrystalline. The angular dependence of the coercivity, HC, of the Ni nanowires presents a smooth variation from a μoHC = 5.5 mT when the field is applied perpendicular to the wires to μoHC = 53 mT when the field is applied parallel to them. However, the Co and Fe nanowires exhibit a peak in the angular dependence of HC for fields applied close to the AAM plane (i.e., perpendicular to the wires). The competition between shape anisotropy and dipolar interactions between the nanowires seems to be responsible for the difference in magnetic behavior between the different metals.

The high concentration of grain boundaries provided by nanostructuring is expected to lower the thermal conductivity of thermoelectric materials, which favors an increase in their thermoelectric figure‐of‐merit, ZT. A novel chemical alloying method has been used for the synthesis of nanoengineered‐skutterudite CoSb3. The CoSb3powders were annealed for different durations to obtain a set of samples with different particle sizes. The samples were then compacted into pellets by uniaxial pressing under various conditions and used for the thermoelectric characterization. The transport properties were investigated by measuring the Seebeck coefficient and the electrical and thermal conductivities in the temperature range 300 K to 650 K. A substantial reduction in the thermal conductivity of CoSb3was observed with decreasing grain size in the nanometer region. For an average grain size of 140 nm, the thermal conductivity was reduced by almost an order of magnitude compared to that of a single crystalline or highly annealed polycrystalline material. The highest ZTvalue obtained was 0.17 at 611 K for a sample with an average grain size of 220 nm. The observed decrease in the thermal conductivity with decreasing grain size is quantified using a model that combines the macroscopic effective medium approaches with the concept of the Kapitza resistance. The compacted samples exhibit Kapitza resistances typical of semiconductors and comparable to those of Si–Ge alloys.

A method to construct synchronous delivery systems via direct self-assembly of Au nanoparticles on the poly[(N-isopropylacrylamide-r-acrylamide)-b-L-lactic acid] (PNAL) nanospheres has been presented in this paper. To achieve amphiphilic diblock terpolymer, hydrophobic poly (L-lactic acid) (PLLA) block was added to poly(N-isopropylacrylamide- r-acrylamide) (PNA) block via Michel-type addition reaction. Lower critical solubility temperature (LCST) was modulated at 35.6 °C which is close to the body temperature, but higher than poly(N-isopropylacrylamide) (PNIPAAm) homopolymer by controlling the ratio between isopropylacrylamide (IPAAm) monomers and acrylamide (AAm) monomers. Using this amphiphilic diblock terpolymer, PNAL nanospheres were fabricated by emulsion/evaporation technique followed by direct self-assembly of Au nanoparticles on the PNAL nanospheres due to the high affinity of amino groups donated from PNA block. The ‘core’ site of Au@PNAL nanospheres can load various lyphophilic drugs. Moreover, Au nanoparticles in the ‘shell’ domain of PNAL nanospheres give optimal environment to conjugate various biomolecules. Therefore, it is expected that Au@PNAL hybrid nanospheres can be utilized in synchronous delivery of both biomolecules in the ‘shell’ domain and various therapeutic drugs in the ‘core’ domain.

Immobilization of bovine serum albumin (BSA) on surface-modified superparamagnetic iron oxide nanoparticles (SPION) has been performed by two different double-step immobilization approaches. The first approach consists of preparation of SPION by controlled chemical coprecipitation in the presence of BSA solution, whereas the second approach includes preliminary surface modification of SPION with an amine group using a coupling agent of 3-aminepropyltrimethoxysilane (APTMS). Both procedures are followed by 1-ethyl-3-(3-dimethylaminepropyl) carbodiimide hydrochloride (EDC) activation with sequential immobilization of the layer of BSA. Additionally, an attempt to modify the surface of SPION with amine and carboxylic groups is undertaken by using l-aspartic acid (LAA). TEM shows that the particle size varies in the range 10−15 nm and does not change significantly after the coating process. The presence of BSA and amine groups on the surface of SPION is confirmed by FT-IR. Magnetic properties are investigated by VSM and results indicate that the superparamagnetic properties are retained for BSA-coated SPION while reducing the value of saturation magnetization (Ms). The binding capacity is estimated from thermogravimetric and chemical analyses. APTMS-coated SPION show higher BSA binding capacity compared to that of coprecipitated SPION in the presence of BSA. In vitro tests have been performed after the functionalization of SPION with LAA and BSA. Human dermal fibroblasts are incubated with the surface-modified SPION for 6 and 24 h to observe cell behavior, morphology, cytoskeletal organization, and interactions between cell and SPION. BSA-coated SPION incubated with cells demonstrated a cell response similar to that of control cells, with no adverse cell damage and no endocytosis, whereas LAA-coated SPION show partial endocytosis without cytoskeletal disorganization.

Superparamagnetic iron oxide nanoparticles (SPION) with an average particle diameter of 6 nm are prepared by controlled chemical coprecipitations. Colloidal suspensions of noninteracting SPION, where the surface has been modified with three different types of biocompatible substances, namely, starch, gold (Au), and methoxypoly(ethylene glycol) (MPEG) have been fabricated via three different techniques. Starch-coated SPION are prepared by coprecipitation in a polymeric matrix, Au-coated SPION are fabricated by the microemulsion method, and MPEG-coated SPION are prepared using the self-assembly approach. The magnetic nanoparticles form a core−shell structure, and the magnetic dipole−dipole interactions are screened by a layer of coating agents. The amounts of coating agents and SPION are indirectly calculated from the thermogravimetric analysis and superconducting quantum interference device measurements by assuming passive oxidation on the surface of the SPION, and the other conditions do not influence the measurements. The dependency of the spectral characteristics of Mössbauer spectroscopy as a function of an external magnetic field Hext is measured to investigate the effect of dipole−dipole screening of the different coating layers on the SPION. Uncoated SPION show a stable magnetic moment under Hext, and the superparamagnetic (SPM) fraction transforms to a ferrimagnetic state. Starch and Au-coated SPION retain the SPM fraction according to Mössbauer spectroscopy and magnetization measurements. MPEG-coated SPION show hyperfine magnetic structure without the quadrupole effect with increasing the value of the blocking temperature.

The sorption behaviour of Co(II) and Hg(II) on 2-nitroso-1-naphthol loaded polyurethane foam (PUF) was studied. The maximum sorption of 1.8×10-5M solution of Co(II) occurred at low pH range 3-7 and that of 3.11×10-5M solution of Hg(II) was sorbed at higher pH range 7-9. The maximum equilibrium was attained within twenty minute shaking time. The adsorption data followed the Freundlich and Langmuir adsorption isotherms successfully. The Freundlich constants 1/nand Kffor Co(II) are 0.44 and 1.18×10-2mol g-1and for Hg(II) are 0.38 and 8.67×10-4mol g-1respectively indicate the surface heterogeneity. The Langmuir constants Mand bare 2.6×10-4mol g-1and 4.7×104L g-1for Co(II) and 2.9×10-5mol g-1and 7.6×104L g-1for Hg(II) respectively. The sorption free energy (E) evaluated from Dubinin–Radushkevich (D–R) isotherm for Co(II) and Hg(II) are 12.7kJ mol-1and 13.13kJ mol-1respectively, which indicate the ion exchange type chemisorption of Co(II) and Hg(II) onto 2-nitroso-1-naphthol loaded PUF. The thermodynamics parameters ΔH, ΔSand ΔGhave been evaluated. The change in enthalpy (ΔH) of Co(II) is 74.55kJ mol-1, indicates the endothermic sorption, while for Hg(II) is -25.28kJ mol-1, depicts the exothermic sorption. The effect of diverse anions on the sorption of Co(II) and Hg(II) has been studied which revealed that the sorption of Hg(II) was completely masked in the presence of bromide, tartrate, nitrite, EDTA, thiocyanate, cyanide, perchlorate, ascorbate and thiourea, whereas sorption of Co(II) was greatly affected in the presence of oxalate, EDTA, cyanide, citrate and ascorbic acid. The nature of sorption mechanism has been discussed. The 2-nitroso-1-naphthol loaded PUF has potential in radiochemistry to separate 203Hg(II) from 75Se(IV), and Co(II) from Ni(II) metal ions or vice versa.

Superparamagnetic iron oxide nanoparticles (SPION) with suitable bio-compatible coatings have been used in biomedicine, particularly in magnetic resonance imaging (MRI), tissue engineering, and drug delivery applications. In this study, we describe the synthesis of SPION and its use for experimental in-vivo applications in MRI. SPION with a mean size of 6 nm have been prepared under inert atmosphere, in a polymeric starch matrix, by controlled chemical coprecipitation of magnetite phase from aqueous solutions containing suitable salts of Fe²⁺ and Fe³⁺. X-ray powder diffraction was used to confirm a pure magnetite phase for the SPION. The influence of oxidizing agents on the cleavage of the starch chains was investigated by changing the concentration of H2O2. An aqueous solution of H2O2/NaOH cleaves the glycosidic bonds and reduces the polymer chains to a critical average molecular weight. From the dynamic light scattering (DLS) size distribution, the bulk agglomeration size was decreased by approximately 50% of the bulk size when treated by H2O2. Freshly synthesized starch-coated SPION in buffered artificial cerebro-spinal fluid were injected into the brain parenchyma of anaesthetized rats for in-vivo monitoring. Analysis of T2*-weighted images and T2*-maps revealed formation of a concentration gradient for the SPION at the injection site, indicating SPION dispersion in the living brain parenchyma from the center of the injection site toward the periphery. The starch-coated SPION show a biocompatibility and possibility of being transported in the extracellular space as well as being internalized in nerve cells.

Magnetic nanoparticles are becoming increasingly important for several biomedical applications. For example, superparamagnetic magnetite nanoparticles with suitable bio-compatible coatings are useful in magnetic resonance imaging, tissue engineering, and drug delivery, etc. In this study we report the synthesis of magnetite nanoparticles and the further coating of these particles by several types of protective layers. Thermodynamic modeling of the chemical system has been adopted as a rational approach to establish routes to better synthesis conditions for pure phase magnetite. Quantitative analysis of different reaction equilibria involved in the precipitation of magnetite from aqueous solutions has been used to determine optimum synthesis conditions. Superparamagnetic magnetite nanoparticles (SPION) with diameters of 6 and 12 nm have been prepared by controlled chemical coprecipitation of magnetite phase from aqueous solutions containing suitable salts of Fe²⁺ and Fe³⁺ under inert atmosphere. Pure magnetite phase SPION could be observed from X-ray diffraction. Magnetic colloid suspensions containing particles with three different types of coatings (sodium oleate (NaOl), starch, and methoxypoly(ethylene glycol) (MPEG)) have been prepared by using different stabilization methods. SPION coatings were studied by determining the change of the surface charge by electrokinetic sonic amplitude (ESA) measurements, as a function of varying NaOl in the solution, where the amount of NaOl needed to form a stable suspension was determined. For stable suspension, the optimum concentration of sodium oleate (NaOl) chemisorbed at 2.5 g of SPION surface is 5.2 × 10^-7 M NaOl which shows maximum ESA value of 0.034 mPa·M/V. SPION coating by starch results in the formation of agglomerate. The agglomeration size of starch-coated SPION can be decreased by introducing H2O2 as an oxidizing agent; the resulting particle size is 42 nm as determined by dynamic light scattering (DLS). For the modification of SPION surfaces with MPEG, the surface was first silanized by 3-aminopropyltrimethoxy silane (APTMS) as a coupling agent with a thickness of two or three molecular layers. AFM image shows that each cluster includes several magnetite single particles with the cluster size around 120 nm. SPION, both coated and uncoated, have been characterized by several techniques. AFM was used to image the MPEG-coated SPION. FTIR study indicated that the different coating agents cover the SPION surface. Magnetic characterization was carried out using SQUID and Mössbauer spectroscopy.

Objectives To study the effect of angiotensin-converting enzyme (ACE) polymorphisms II, ID, and DD on erythropoietin (EPO) requirement in patients on continuous ambulatory peritoneal dialysis (CAPD) therapy.Design Retrospective observational study.Setting CAPD Unit, Royal London/St. Bartholomews Hospital, London, UK.Patients 46 patients on the transplant waiting list (age 20 – 70 years), on CAPD therapy for an average of 28 months, seen consecutively over a period of 3 months in the outpatients department.Main Outcome Measures Primary end point: EPO dose requirement in different ACE genotypes. Secondary end points: C-reactive protein, ferritin, parathyroid hormone, Kt/V, duration of dialysis, folate, cause of renal failure, and whether or not patients were on ACE inhibitor therapy.Results There was a statistically significant difference (p< 0.05) in EPO requirement in the II/ID group compared to the DD group. The mean ± standard error of EPO for the II/ID group was 144 ± 15 U/kg/week, and for the DD group, 87 ± 9 U/kg/ week. The difference in EPO requirement could not be explained by age, C-reactive protein, ferritin, parathyroid hormone, Kt/V, duration of dialysis, folate, cause of renal failure, or whether or not patients were on ACE inhibitor therapy.Conclusion In CAPD patients, ACE genotype has predictive value when determining the EPO dosage, as the II/ID genotype may be associated with a suboptimal response.

The deprotonation of quinolic resin P-127 and iminodiacetic resin Amberlite IRC-718 has been studied. The process of salt transfer into the resin phase is considered to be an important contributor to the deprotonation process. Estimation of the salt transfer was based on the principle of equal activity of the salt in both phases at equilibrium. Two assumptions were made:  sorbed alkali metal ions are not associated with functional groups, while all hydrogen ions are associated with functional groups. The associated hydrogen ions and functional groups do not contribute to the internal ionic strength value. Two thermodynamic models, describing the deprotonation of ion-exchange resin, were used and compared:  the Gibbs−Donnan-based model of Bukata and Marinsky and the model proposed by Erik Högfeldt. Thermodynamic characteristics of the resins' deprotonation are obtained using two different thermodynamic approaches. Högfeldt's three-parameter model provides a better agreement with experimental data. The fitting of the data to Marinsky's method can be improved by taking into account the influence of the resins' macroporosity; however, this requires an additional empirical parameter to describe the resin.

The formation of solid solutions of cerium oxide with the oxides of calcium, manganese, or neodymium enhances the catalytic activity of cerium oxide for the total oxidation of methane, whereas solid solutions with lead oxide showed an opposite effect. Reasons for this are discussed in terms of oxygen vacancy concentrations and mobilities, local structure configurations, number of oxidation states of dopant, and electron transfer properties. The effects of increased oxygen ion mobility and a more beneficial local structure support the increased catalytic activity for the calcium- and neodymium-doped cerium oxide samples. In addition, a reduced energy for charge transfer from oxygen to cerium supports a higher activity for the calcium-doped sample. The activity data were fitted to an Arrhenius equation, and the apparent activation energies were found to be between 110 and 130 kJ/mol. The particle sizes and the BET areas of the samples were only little affected by the reactor runs, and none of the samples were subjected to phase changes.

The thermoelectric materials CoSb3 with Skutterudite structure, have been prepared via a chemical solution route. A precursor consisting of a well-defined mixture of Co oxalate and Sb oxide in a ratio of 1:3 mole was prepared. The precursor was calcined and reduced under hydrogen atmosphere whereby the CoSb3 with Skutterudite structure has been thus obtained. The materials obtained at the various processing steps were characterised by SEM, XRD, TGA and BET techniques.