Full Reduction Research Articles

Derotation of the mallet piece: A crucial point in mallet fracture surgery

Mallet fracture is an avulsion of the extensor tendon and fracture of the dorsal rim of the articular surface of distal phalanx at the same time. If a part of the mallet fracture is angled or rotated to such a degree that prevents full anatomic reduction, malunion and deformities may occur as a result. The objective of this study was to describe a new surgical technique to provide derotation of the mallet fracture. A 22G or 21G needle is used like a joystick to reduce the mallet fracture with small, gentle movements. The extension block pinning technique described by Ishiguro was applied after proper alignment had been achieved. Bony union was achieved for all patients 6 weeks later. Derotation of type 2 and 3 mallet pieces with closed reduction to prevent surgical failure is simple but effective.

Comparison of different chemical cleaning reagents on fouling recovery in a Self-Forming dynamic membrane bioreactor (SFDMBR)

Abstract Self-forming dynamic membrane bioreactor (SFDMBR) using large pore size (>5 μm) membrane material is regarded as a cost-effective technology with less fouling and high permeate flux. However, no successful long-term operation without chemical cleaning is achieved. Therefore, an optimum chemical cleaning reagent needs to be explored with the understanding of foulants structure. This study compared the cleaning effects of three typical chemical cleaning reagents, i.e. sodium hydroxide (NaOH), sodium hypochlorite (NaClO), and sodium dodecyl sulfate (SDS), using a lab-scale SFDMBR. NaClO is identified as the most effective cleaning reagent in view of its trans-membrane pressure (TMP) reduction and permeability recovery efficiency. NaClO could achieve 99.0% of permeability recovery and full TMP reduction, while NaOH and SDS could only recover 87.7% and 76.5% of initial permeability and showed limited efficiency in TMP reduction, although all three reagents can achieve over 70% of extracellular polymeric substances (EPSs). The major foulant of the SFDMBR was a complex mixture of sludge flocs with EPS. NaClO cleaning can largely remove the flocs and EPS by oxidization effects while NaOH and SDS were only effective in EPS removal, which explained why NaClO cleaning showed the best performance. β-polysaccharide attached on the mesh fibers and acted as the binding substance between the foulants and mesh fibers is the main reason for irremovable inner pore fouling, which only could be significantly removed with NaClO cleaning. These results well explain the difference of filtration performance after three types of chemical cleaning.

Thin-film nano-thermogravimetry applied to praseodymium-cerium oxide films at high temperatures

High precision measurements of oxygen nonstoichiometry δ in thin film metal oxides MaOb±δ at elevated temperatures and controlled oxygen partial pressures pO2 are reported with the aid of resonant microbalances. The resonant microbalances applied here consisted of y-cut langasite (La3Ga5SiO14) and CTGS (Ca3TaGa3Si2O14) piezoelectric resonators, operated in the thickness shear mode at ∼5 MHz. Measurements of variations in δ of Pr0.1Ce0.9O2-δ (PCO) films are reported for the oxygen partial pressure range from 10−8 bar to 0.2 bar at 700 °C, and these results were found to be in good agreement with previously reported oxygen nonstoichiometry δ data derived from chemical capacitance studies. The PCO thin-films were deposited via pulsed laser deposition on both sides of the resonators, whose series resonance frequency was tracked, converted into mass changes and, finally, into nonstoichiometry. The nonstoichiometry was observed to reach a plateau as the oxygen partial pressure dropped below about 10−5 bar, the behavior being attributed to the full reduction of Pr to the trivalent state. These resonators enable stable operation up to temperatures above 1000 °C, thereby maintaining high mass resolution suitable for determining oxygen nonstoichiometry variations in thin films deposited on such resonators. For the given experimental conditions, a mass resolution of ∼50 ng was achieved at 700 °C with the CTGS resonator.

Surface analysis of fine water‐atomized iron powder and sintered material

Press and sinter is a core technology in powder metallurgy in which a metal powder is mixed with a lubricant and other additives and subsequently compacted at large mechanical pressures to create the desired shape. The component is then delubricated and finally sintered to strengthen the material. The end result of the sintering depends on both the physical properties of the powder such as particle size, morphology, and size distribution, as well as chemical properties like surface chemical composition and presence of surface oxides. In this study, the surface characteristics of 3 fractions of water‐atomized iron powder, sieved to −20, −45, and −75 μm, were investigated. This was done by using X‐ray photoelectron spectroscopy, Auger electron spectroscopy, and scanning electron microscopy equipped with energy‐dispersive X‐ray spectroscopy. The powder was sintered while performing thermogravimetric analysis at 1350°C for 30 minutes in pure hydrogen. Results showed that powder of all 3 size fractions were mainly covered by a thin iron oxide layer but with some presence of submicron‐sized oxide particulates. X‐ray photoelectron spectroscopy and thermogravimetric analysis showed reasonable agreement on the oxide layer thickness, while a size dependence was found with an enrichment of oxide particulates on the finer powder fractions. Fracture surfaces of the sintered material were analyzed with X‐ray photoelectron spectroscopy and scanning electron microscopy + energy‐dispersive X‐ray spectroscopy, which indicated that full reduction of all oxides was achieved. The sintering conditions were further related to the surface properties of the powder and its size fraction.

Steam reforming of acetic acid over Ni/Al2O3 catalyst: Correlation of calcination temperature with the interaction of nickel and alumina

This study investigated the interaction of nickel species with alumina versus calcination temperature and nickel loading. A total of 22 Ni/Al2O3 catalysts, calcined at the temperature from 500 to 1000 °C at a 50 °C increment, were employed for the study. High calcination temperature led to the formation of nickel–alumina spinel via the solid phase reaction, which shifted the reduction temperature to higher ranges. The catalyst, however, still achieved good activity after full reduction of the nickel–alumina spinel. Nevertheless, the high calcination temperature led to the collapse of the small pores and the formation of the big one, resulting in the significant decrease of specific surface area. At higher nickel loadings, more nickel species weakly interacted with alumina formed as the reactive center of alumina was saturated. With the increase of nickel loading, the catalytic activities were not varied much but the catalytic stability and the resistivity towards coking enhanced. The coke produced over the catalyst at low nickel loading tended to be amorphous, while the coke produced at the high nickel loading was more fibrous. Furthermore, the coke produced at the low loading contained more small aromatic rings and more oxygen-containing functional groups. The higher nickel loading possibly promoted the catalytic cracking reactions to form more catalytic coke while the low nickel loading probably favored the polymerization reactions to form the polymeric coke. In addition, the calcination at the higher temperature could enhance the stability of the catalysts, which might be related to the enlarged pore sizes.

Inhibition of Surface Chemical Moieties by Tris(hydroxymethyl)aminomethane: A Key to Understanding Oxygen Reduction on Iron–Nitrogen–Carbon Catalysts

The effect of tris(hydroxymethyl)aminomethane (Tris) on the activity of metal–nitrogen–carbon (M–N–C) platinum metal group-free (PGM-free) catalysts for oxygen reduction reaction (ORR) is studied. Electrochemical tests performed in the acidic and alkaline electrolyte and comparison between electrochemical observations for metal-free and metal-containing catalysts along with density functional calculations showed the multiplex mechanism of oxygen reduction in which numerous species perform partial and full reduction of oxygen to peroxide or water, respectively. The important role of protons in the mechanism of oxygen reduction is highlighted.

Hierarchical hybrid sandwiched structure of ultrathin graphene nanosheets enwrapped MnO nanooctahedra with excellent lithium storage capability

Graphene supported transition metal oxides (TMOs) nanocomposites have been recognized as an advisable strategy to develop the advanced electrodes for lithium-ion batteries (LIB) recently, yet the long-term cyclic stability could not be well maintained mainly due to the severe structural collapse and continuous exfoliation of active TMOs from graphene support. Herein, we successfully designed a novel sandwich-type hybrid nanostructure of reduced graphene oxide (rGO) enwrapped MnO nanooctahedra like a blanket (MnO@rGO NO) via a facile solution reflux and a post-annealing. The XRD patterns and FESEM images confirm that octahedral Mn3O4 precursor embedded among GO interlayers could be easily reduced into conformal MnO nanocrystal whilst the full reduction of GO into rGO during the subsequent calcination at 700 °C in N2. When used as a promising anode for LIBs, the sandwiched MnO@rGO NO manifests excellent lithium storage capability with high reversible discharge capacity, long-term cyclic stability and superb rate performance, mainly benefiting from the robust structure and good conductivity enhanced by rGO matrix. Even undergoing 600 cycles at the current densities of 400 and 800 mA g−1, the hybrid sandwiched MnO@rGO NO anodes could still deliver stable discharge capacities of 838 and 687 mAh g−1, respectively.

Insights into Elevated-Temperature Photocatalytic Reduction of CO2 by H2O

Photocatalytic reduction of CO2 for the production of synthesis gas, hydrocarbons, alcohols, or aldehydes from only CO2, H2O, and solar radiation may be a promising route to recycle CO2 waste at the source of its production, reduce atmospheric CO2 through direct removal from Earth’s atmosphere, and/or produce CH4 rocket fuel on Mars. In this study, we present the first studies of high-temperature (350 °C) photocatalytic reduction of CO2 in the gas phase over a suite of semiconductors with a range of surface chemical reactivity and bulk electronic properties, namely, SiC, Si, Pt/TiO2, and GaN. The results indicate that catalysts that exhibit high Debye temperatures and elevated surface reactivity may enable the production of new reaction intermediates that facilitate C–O cleavage and full CO2 reduction to CH4. Elevated photocatalyst surface reactivity also correlated with dramatically improved selectivity between hydrogenation (CH4 production) and H2 evolution, for example, 1:8, 1:71, 1:400, and 1:1000+ fo...

Reduction of graphene oxide by UHV annealing

A series of chemically treated graphene oxide (GO) samples, destined for the preparation of several composite materials, was studied by X‐ray photoelectron spectroscopy (XPS). From their comparison, the 3‐mercaptopropyl trimethoxysilane was identified as the most effective reducing agent among the used procedures. The influence of ultrahigh vacuum annealing up to 600°C on the chemical composition and carbon electronic configuration in reduced GO samples was further investigated by XPS and Auger electron spectroscopy. All the samples before and after thermal treatments were analyzed in situ by XPS and Auger electron spectroscopy, paying a particular attention to the shape of C KVV spectra described by the values of D parameter. The changes of chemical composition and carbon configuration reflected in the D parameter revealed the full reduction of GO to graphene after annealing in ultrahigh vacuum at 600°C. The successful reduction of GO to graphene was also confirmed by Raman spectroscopy. Obtained bulk samples of graphene aggregates remained stable in air, testifying the irreversibility of this reduction.

In Situ Elucidation of the Active State of Co–CeOx Catalysts in the Dry Reforming of Methane: The Important Role of the Reducible Oxide Support and Interactions with Cobalt

The activation of methane and its dry reforming with CO2 was systematically studied over a series (2–30 wt %) of Co (∼5 nm in size) loaded CeO2 catalysts, with an effort to elucidate the interplay between Co and CeO2 during the catalytic process using in situ methods. The results of in situ time-resolved X-ray diffraction (TR-XRD) show a strong interaction of methane with the CoOx–CeO2 systems at temperatures between 200 and 350 °C. The hydrogen produced by the dissociation of C–H bonds in methane leads to a full reduction of Co oxide, Co3O4 → CoO → Co, and a partial reduction of ceria with the formation of some Ce3+. Upon the addition of CO2, a catalytic cycle for dry reforming of methane (DRM) was achieved on the CoOx–CeO2 powder catalysts at temperatures below 500 °C. A 10 wt % Co–CeO2 catalyst was found to possess the best catalytic activity among various cobalt loading catalysts, and it exhibits a desirable stability for the DRM with a minimal effect of carbon accumulation. The phase transitions and ...

Site-specific and hydrophilic ADCs through disulfide-bridged linker and branched PEG

Kadcyla® (T-DM1), an antibody–drug conjugates (ADCs) for HER2+ breast cancer treatment, has been approved by the Food and Drug Administration (FDA) in 2013. An ADC of random lysine conjugation, it has difficulties in DAR control and unsatisfactory PK due to uneven DAR distribution. It also gives rise to aggregation during conjugation because of the hydrophobicity nature of the cytotoxin, DM1. The linker-drug in T-DM1, SMCC-DM1 is hydrophobic and requires certain percentage of organic solvent such as DMA in the conjugation solution, limiting the manufacturing process in an organic-solvent-compatible device and adding extra costs. To address these problems, a site-specific conjugation method was developed involving full reduction of antibody and full conjugation with the bridge-like conjugator-drug, based on the work of Caddick and co-workers, to obtain a site-directed antibody-drug conjugate with DAR 4. The bridge-like conjugator was assembled with SMCC-DM1 and different lengths of hydrophilic polyethylene glycol (PEG) moiety. By applying PEG moiety in the side chain of the linker-drug, the organic solvent used in the conjugation can be reduced. When the PEG length is about 26 units, organic solvent is no longer needed in the conjugation. Reducing the amount of organic solvent in conjugation could also diminish the aggregation occurrence during the conjugation. Moreover, the conjugation configuration with the designed conjugator was also discussed in the article. The binding affinity of the resulting ADCs did not show significant decrease and the cell based assay and animal study have shown the comparable results with T-DM1.

Results of surgical treatment of acromioclavicular dislocations type III using modified Weaver Dunn technique

ObjectiveTo evaluate the clinical and radiological results of the surgical treatment of type III acromioclavicular dislocations using the Weaver–Dunn technique in the delayed phase. Material and methodA non-randomised controlled retrospective observational study of 38 patients operated between January 2006 and December 2014. We excluded 10 patients due to death or non-localisation. We collected demographic data, time to intervention, complications, analysing the Visual Analogue Scale, DASH and Oxford Shoulder Score and the updated radiological result. ResultsMean age of patients with right-dominant shoulder affected in 71% of cases predominantly by non-level falls was 35. 70% of the cases had subjective perception of both recovery of strength and disappearance of deformity. Full radiological reduction was observed in 95% of the cases with the appearance of mild osteoarthritis in 44% and moderate osteoarthritis in 5.6%. The results of the DASH presented values of 12.939 (±16.851) and the OSS of 42.736 (±7.794), indicating satisfactory articular function. DiscussionThe data from this study shows similar results to previous studies regarding subjective recovery of strength, maintenance of anatomical reduction, functional test results and efficacy of the Weaver–Dunn technique. ConclusionsThe modified Weaver–Dunn technique provided good clinical and radiological results with patient reincorporation to their usual activities and maintenance over time.

Synthesis of Tin Powder Using Tin Oxide and Ethanol

The reduction behavior of SnO2 powder has been investigated in the temperature range of 900–1200 K under ethanol flow. Scanning electron microscopy, x-ray diffraction, and mass measurement techniques were used to characterize the products. Full oxide reduction was attained at 1000 K, 1100 K, and 1200 K within about 20 min, 15 min, and 7.5 min, respectively. At 900 K, the extent of reduction increased with the reaction time up to 20 min, but further increases in the time (30 min and 60 min) resulted in a slight mass gain. This was attributable to the C uptake. Spherical Sn particles (diameter ~ 1 μm) were observed at 1000 K and 1100 K. At 1200 K, large beads of Sn (diameter 400–800 μm) were obtained. The spherical particle morphology was attributed to the liquid metallic phase formed during the reaction. The reduction mechanism of SnO2 in ethanol has been discussed in the light of thermodynamic and experimental results.

Oxygen reduction reaction (orr) on bimetallic AuPt and AuPd(1 0 0)–electrodes: Effects of the heteroatomic junction on the reaction paths

The seek for materials to enhance the oxygen reduction reaction (orr) rate is a highly relevant topic due to its implication in fuel cell devices. Herein, the orr on bimetallic electrocatalysts based on Au-M (M = Pt, Pd) has been studied computationally, by performing density functional theory calculations. Bimetallic (100) electrode surfaces with two different Au:M ratios were proposed, and two possible pathways, associative and dissociative, were considered for the orr. Changes in the electronic properties of these materials with respect to the pure metals were acknowledged to gain understanding in the overall reactivity trend. The effect of the bimetallic junction on the stability of the intermediates O2 and OOH was also evaluated by means of geometrical and energetic parameters; being the intermediates preferably adsorbed on Pt/Pd atoms, but presenting in some cases higher adsorption energies compared with bare metals. Finally, the kinetics of the OO bond breaking in O2∗ and OOH∗ adsorbed intermediates in the bimetallic materials and the influence of the Au-M junction were studied by means of the nudge elastic-band method. A barrierless process for the scission of O2∗ was found in Au-M for the higher M ratios. Surprisingly, for Au-M with lower M ratios, the barriers were much lower than for pure Au surfaces, suggesting a highly reactive surface towards the orr. The OO scission of the OOH∗ was found to be a barrierless process in AuPt systems and nearly barrierless in all AuPd systems, implying that the reduction ofO2 in these systems proceeds via the full reduction of O2 to H2O, avoiding H2O2 formation.

Resultados del tratamiento quirúrgico de las luxaciones acromioclaviculares tipo iii mediante técnica de Weaver-Dunn modificada

ObjectiveTo evaluate the clinical and radiological results of the surgical treatment of type III acromioclavicular dislocations using the Weaver-Dunn technique in the delayed phase. Material and methodA non-randomised controlled retrospective observational study of 38 patients operated between January 2006 and December 2014. We excluded 10 patients due to death or non-localisation. We collected demographic data, time to intervention, complications, analysing the Visual Analog Scale, DASH and Oxford Shoulder Score and the updated radiological result. Resultsmean age of patients with right-dominant shoulder affected in 71% of cases predominantly by non-level falls was 35. 70% of the cases had subjective perception of both recovery of strength and disappearance of deformity. Full radiological reduction was observed in 95% of the cases with the appearance of mild osteoarthritis in 44% and moderate osteoarthritis in 5.6%. The results of the DASH presented values of 12,939 (±16,851) and the OSS of 42,736 (±7,794), indicating satisfactory articular function. DiscussionThe data from this study shows similar results to previous studies regarding subjective recovery of strength, maintenance of anatomical reduction, functional test results and efficacy of the Weaver-Dunn technique. ConclusionsThe modified Weaver-Dunn technique provided good clinical and radiological results with patient reincorporation to their usual activities and maintenance over time.

Efficient reduction of Cr(VI) under visible light irradiation using CuS nanostructures

Photoreduction of hexavalent chromium, Cr(VI), identified as carcinogenic and mutagenic element, to Cr(III), believed to be an essential element, using copper sulfide nanostructures (CuS NSs) as photocatalyst was investigated under visible light irradiation (λ > 420 nm). The CuS NSs were synthesized at low temperature using a wet chemical route and fully characterized using various techniques such as scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy and UV–vis spectrophotometry. The photocatalytic reduction of Cr(VI) using visible light irradiation was assessed by UV–vis by following the decrease of the characteristic absorbance at ∼352 nm in the presence of CuS NSs. While CuS NSs promoted Cr(VI) full reduction within 60 min, addition of adipic acid or formic acid accelerated significantly the photocatalytic reduction process. Under optimized conditions, CuS NSs rapidly (12 min) reduced Cr(VI) in presence of 0.5 mM adipic acid. Similarly, Cu NSs were found to be efficient for Cr(VI) reduction dissolved in water from a local lake. Stability studies showed that the photocatalyst could be recycled up to four times without any apparent decrease of its catalytic performance.

Voltage THD Analysis Using Knowledge Discovery in Databases With a Decision Tree Classifier

Industrial production has evolved significantly over the last decade. For this reason, it is necessary to obtain mathematical and computational tools that enable power systems engineers to make decisions that reduce harmonic distortions in accordance with international standards. This paper presents a total harmonic distortion (THD) assessment based on full knowledge discovery in databases (KDD) using power quality (PQ) standards and computational intelligence tools. The materials and methods of THD assessment consist of load and layout analysis; choice and installation of PQ analyzers; and the application of the full KDD process, including collection, selection, cleaning, integration, transformation and reduction, mining, interpretation, and evaluation of the data. This research methodology was used in an electrical and electronic industry; the results obtained have characteristics that can be used as a reference for other types of analyses. The results indicate that these methods can be applied to several industrial applications such as: 1) the description of the complete KDD process for THD assessment of the point of common coupling; 2) simultaneous collection using five PQ analyzers at several points in the electrical network; and (3) the use of a decision tree classifier.

Low temperature prepared copper-iron mixed oxides for the selective CO oxidation in the presence of hydrogen

Copper-iron mixed oxides with Fe/Cu molar ratios ranging from pure CuO to Fe2O3 were synthesised by a low temperature co-precipitation method, and tested in the CO-PROX reaction. The extensive characterization performed by means of different techniques showed the progressive variation of physical and chemical properties including composition, texture, structure and reducibility of the prepared oxides. Rietveld analysis of X-ray diffraction data, XPS and Raman spectra, and especially TEM study revealed the formation of CuFe2O4. All the samples were more active and selective below 200 °C than a commercial Pt/Al2O3 catalyst used as a reference. In particular, the catalyst having a 2 Fe/Cu molar ratio, corresponding to the cuprospinel stoichiometry, exhibited the best performance with a 76% conversion and a 60% selectivity at 125 °C, operating with 50% of H2 in the gas stream, being relatively stable in long-term time-on-stream experiments. On the contrary, pure CuO rapidly deactivated in the course of reaction at 150 °C. Differences in catalytic stability were related to a promoting effect of iron in the mixed oxide which makes copper more resistant to full reduction.

Assessment of deep inspiration breath hold (DIBH) amplitude and reduction in cardiac dose in left breast cancer patients

IntroductionThe primary aim of this study was to examine the impact of deep inspiration breath-hold (DIBH) amplitude on subsequent mean heart dose and V30 during radiotherapy. The secondary aim was to investigate if patient age influenced DIBH amplitude. MethodA retrospective study of 30 patients with left-sided breast cancer was completed. Patients were randomly selected from the total number of patients dual scanned in free breathing (FB) and DIBH over a 2-year period. Plans were retrospectively virtually simulated and statistical analysis performed. ResultsAll patients achieved decreased V30 and mean cardiac dose using DIBH. A positive correlation was found between DIBH amplitude and cardiac V30 dose reduction (p = 0.007, R = 0.48). Ratio of amplitude increase from FB to DIBH and cardiac V30 reduction was positively correlated and statistically significant (p = 0.04, R = 0.38); Ratio of amplitude increase of at least 15 times FB achieved 100% V30 dose reduction, however this was also achieved with ratio increase as low as 6.25 times FB. A statistically significant positive correlation was identified between DIBH amplitude and mean cardiac dose reduction (p = 0.003, R = 0.523). No correlation was found between patient age and amplitude ratio increase (p = 0.602, R = −0.099). ConclusionA 100% reduction in cardiac V30 can be achieved with a DIBH amplitude increase of 15 times FB. A full reduction can also be achieved at much lower levels (6.25 times FB in current study); however there appears to be no pre-determining patient factors to identify this. DIBH amplitudes of 1 cm–4 cm reduce cardiac mean dose by at least 50%.

Modulation of O2 reduction in Saccharomyces cerevisiae mitochondria

Respiratory supercomplex factor (Rcf) 1 is a membrane-bound protein that modulates the activity of cytochrome c oxidase (CytcO) in Saccharomycescerevisiae mitochondria. To investigate this regulatory mechanism, we studied the interactions of CytcO with potassium cyanide (KCN) upon removal of Rcf1. While the addition of KCN to the wild-type mitochondria results in a full reduction of heme a, with the rcf1Δ mitochondria, a significant fraction remains oxidized. Upon addition of ascorbate in the presence of O2 and KCN, the reduction level of hemes a and b was a factor of ~2 larger with the wild-type than with the rcf1Δ mitochondria. These data indicate that turnover of CytcO was less blocked in rcf1Δ than in the wild-type mitochondria, suggesting that Rcf1 modulates the structure of the catalytic site.