bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photoelectrochemical Behavior of Planar and Microwire‐Array Si|GaP Electrodes
Authors: Strandwitz Nicholas C. , Turner‐Evans Daniel B. , Tamboli Adele C. , Chen Christopher T. , Atwater Harry A. , Lewis Nathan S. 
Published: June 2012

AbstractGallium phosphide exhibits a short diffusion length relative to its optical absorption length, and is thus a candidate for use in wire array geometries that allow light absorption to be decoupled from minority carrier collection. Herein is reported the photoanodic performance of heteroepitaxially grown gallium phosphide on planar and microwire‐array Si substrates. The n‐GaP|n‐Si heterojunction results in a favorable conduction band alignment for electron collection in the silicon. A conformal electrochemical contact to the outer GaP layer is produced using the ferrocenium/ferrocene (Fc+/Fc) redox couple in acetonitrile. Photovoltages of ∼750 mV under 1 sun illumination are observed and are attributed to the barrier formed at the (Fc+/Fc)|n‐GaP junction. The short‐circuit current densities of the composite microwire‐arrays are similar to those observed using single‐crystal n‐GaP photoelectrodes. Spectral response measurements along with a finite‐difference‐time‐domain optical model indicate that the minority carrier diffusion length in the GaP is ∼80 nm. Solid‐state current–voltage measurements show that shunting occurs through thin GaP layers that are present near the base of the microwire‐arrays. The results provide guidance for further studies of 3D multi‐junction photoelectrochemical cells.
Active MnOx Electrocatalysts Prepared by Atomic Layer Deposition for Oxygen Evolution and Oxygen Reduction Reactions
Authors: Pickrahn Katie L. , Park Sang Wook , Gorlin Yelena , Lee Han‐Bo‐Ram , Jaramillo Thomas F. , Bent Stacey F. 
Published: June 2012

AbstractThe ability to deposit conformal catalytic thin films enables opportunities to achieve complex nanostructured designs for catalysis. Atomic layer deposition (ALD) is capable of creating conformal thin films over complex substrates. Here, ALD‐MnOx on glassy carbon is investigated as a catalyst for the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR), two reactions that are of growing interest due to their many applications in alternative energy technologies. The films are characterized by X‐ray photoelectron spectroscopy, X‐ray diffraction, scanning electron microscopy, ellipsometry, and cyclic voltammetry. The as‐deposited films consist of Mn(II)O, which is shown to be a poor catalyst for the ORR, but highly active for the OER. By controllably annealing the samples, Mn2O3 catalysts with good activity for both the ORR and OER are synthesized. Hypotheses are presented to explain the large difference in the activity between the MnO and Mn2O3 catalysts for the ORR, but similar activity for the OER, including the effects of surface oxidation under experimental conditions. These catalysts synthesized though ALD compare favorably to the best MnOx catalysts in the literature, demonstrating a viable way to produce highly active, conformal thin films from earth‐abundant materials for the ORR and the OER.
Compatible blends of polypropylene with an amorphous polyamide
Authors: Aranburu N. , Eguiazabal J. I. 
Published: June 2012

AbstractCompatible polymer blends of polypropylene (PP) with an amorphous polyamide (aPA) were obtained through reactive compatibilization by adding 20% maleic anhydride‐modified copolymer (PP‐g‐MA) to the blends. The blends were made up of a pure PP phase and an aPA‐rich phase where very small amounts of PP were detected. The dispersed phase particle size decreased considerably indicating that compatibilization occurred. Young's modulus of the compatibilized blends increased with respect to that of the uncompatibilized ones. The compatibilized blends were highly ductile, and the impact strength also improved, proving that compatibilization occurred under a broad range of experimental conditions. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013
A polyurethane‐based nanocomposite biocompatible bone adhesive
Authors: Schreader Kevin J. , Bayer Ilker S. , Milner Derek J. , Loth Eric , Jasiuk Iwona 
Published: June 2012

AbstractA novel polyurethane‐based foam‐like adhesive reinforced with nanosized hydroxyapatite (HA) particles was developed and investigated for bone‐to‐bone bonding applications in terms of mechanical adhesion and biocompatibility. The adhesive has a hierarchical structure with HA particles at the nanoscale level and pores at the micro‐scale level. This adhesive was tested mechanically in the three principal loading modes anticipated: shear, tension, and compression. Standard testing procedures were used when available. Tensile strength of primed adhesive showed a four‐fold increase in adhesion on unmodified bone and a nearly two‐fold increase in adhesion to primed bone as compared with the conventional bone cement. Biocompatibility was initially assessed in vitro using cell culture tests, which showed positive interaction with the adhesive. Then, a second biocompatibility test was performed using Xenopus laevis limbs to assess an in vivo response. The results indicated that the adhesive material produces a normal response consistent with control specimens. However, long‐term observations and tests with additional species are needed to demonstrate full biocompatibility. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013
Effect of anionic/siloxy groups on the release of ofloxacin from soft contact lenses
Authors: Yamazaki Y. , Matsunaga T. , Syohji K. , Arakawa T. , Sato T. 
Published: June 2012

AbstractFor the treatment of ocular diseases, chemotherapeutic antibiotics, for example, Ofloxacin, are usually administrated through the application of eye drops during ophthalmic perioperative sterilization. However, this approach has several drawbacks, such as the need for frequent application caused by tears draining the drugs out of the eyes or the presence of a possible contraindication of eye drops when contact lenses are worn. To overcome these problems, we have studied contact lenses composed of hydrogels, which function as a type of drug delivery system technology. We synthesized hydrogels to be used as contact lenses with sufficient amounts of drug uptake and release profiles for sterilization treatment during the perioperative period in ophthalmic areas. This study showed that the hydrogels that included side‐chain ionic groups and silyl groups were useful materials to prepare drug delivery contact lenses. The ionic groups in the hydrogels could functionally retain a drug if an ionic substituent was present. It is noteworthy that the drug content in the contact lenses could readily be controlled by changing the ratio of ionic monomer contents during polymerization. Furthermore, the controlled drug release of silyl‐group‐containing hydrogels showed sustained release over 72 h, which indicated that the hydrogels could be used as contact lenses for sustained drug release. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013
Evaluation of natural rubber specific heat capacity at high pressures from DSC experimental data at atmospheric pressure
Authors: Ortiz‐Serna P. , Díaz‐Calleja R. , Sanchis M. J. 
Published: June 2012

AbstractThe natural rubber specific heat capacity dependence on pressure was estimated on thermodynamic grounds on the basis of the values empirically determined from differential scanning calorimetry data, (in the temperature range of −70 to 50°C), and by means of the Tait equation of state (in the pressure range of 0.1–240 MPa). It was found that the specific heat capacity decreases with pressure, being the dependency more pronounced at low pressures. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013
Synthetic biology challenges long‐held hypotheses in translation, codon bias and transcription
Authors: Forster Anthony C. 
Published: June 2012

AbstractSynthetic biology is a powerful experimental approach, not only for developing new biotechnology applications, but also for testing hypotheses in basic biological science. Here, examples from our research using the best model system, Escherichia coli, are reviewed. New evidence drawn from synthetic biology has overturned several long‐standing hypotheses regarding the mechanisms of transcription and translation: (i) all native aminoacyl‐tRNAs are not equally efficient in translation at equivalent concentrations; (ii) accommodation is not always rate limiting in translation, and may not be for any aminoacyl‐tRNA; (iii) proline is the only N‐alkyl‐amino acid in the genetic code not because of special suitability for protein structure, but because of its comparatively high nucleophilicity; (iv) the usages of most sense codons in E. coli do not correlate with cognate tRNA abundances and (v) class II transcriptional pausing and termination by T7 RNA polymerase cannot be assumed to occur in vivo based on in vitro data. Implications of these conclusions for the biotechnology field are discussed.
Hans Böker – Biomorphologe, Amazonasforscher und Holist
Authors: Hoßfeld Uwe , Levit Georgy S. 
Published: June 2012

AbstractSeit etwa 1917 postulierte Hans Böker einen Forschungsansatz, den er als “vergleichende biologische Anatomie” (biologische Morphologie, Biomorphologie) bezeichnete. Dieses Konzept ging von Beobachtungen des Verhaltens lebender Tiere in der freien Natur aus, verglich dabei deren Verhaltensweisen und hinterfragte die Sachverhalte anatomisch.
Multivisceral resections for rectal cancer
Authors: Smith J D , Nash G M , Weiser M R , Temple L K , Guillem J G , Paty P B 
Published: June 2012

Abstract

Background
En bloc resection of adjacent pelvic organ(s) may be needed to achieve clear surgical margins in rectal cancer surgery. An institutional experience is reported with perioperative morbidity and oncological outcomes.

Methods
Patients were identified retrospectively from a prospectively collected institutional database (1992–2010). Outcomes, and clinical and pathological factors were determined from medical records. Estimated overall survival, overall recurrence and local recurrence were compared using the log rank method and Cox regression analysis.

Results
Among 1831 patients with rectal cancer, 124 (6·8 per cent) underwent en bloc resection of part or all of an adjacent organ (vagina/uterus/ovary 90, prostate/seminal vesicle 23, bladder/ureter 15, small bowel/appendix 7). Five-year overall survival and local recurrence rates were 53·3 and 18·8 per cent respectively. There was one postoperative death, from multiple organ failure in a patient with liver cirrhosis. Fifty-two patients underwent sphincter-preserving surgery and three (6 per cent) developed an anastomotic leak. On univariable analysis, the only factor associated with local recurrence was completeness of resection (local recurrence rate 15 per cent versus 69 per cent for R0 versus R1 resection; P &lt; 0·001). On multivariable analysis, factors associated with overall survival were sphincter-preserving surgery, absence of metastatic disease and R0 resection.

Conclusion
Multiple organ resection for locally advanced primary rectal cancer had good oncological outcomes when clear resection margins were achieved.
Relationship between patients' reports of complications and symptoms, disability and quality of life after surgery
Authors: Grosse Frie K , van der Meulen J , Black N 
Published: June 2012

Abstract

Background
Patient-reported complications are increasingly being used to compare the performance of surgical departments. The objectives of this study were to explore the validity of patient-reported complications and to determine their influence on patients' reports of the benefits of surgery (health gain).

Methods
This was an observational study of patients in England who underwent hip replacement (68 391), knee replacement (77 705), inguinal hernia repair (48 199) or varicose vein surgery (16 535) during 2009–2011. Health gain was assessed with condition-specific measures of symptoms and disability (Oxford Hip Score, Oxford Knee Score, Aberdeen Varicose Vein Questionnaire), health-related quality of life (EQ-5D™ index) and a single item on the success of surgery. Adverse outcomes included four complications, readmission and further surgery.

Results
There was evidence that patient-reported complications were valid. Patients with three or more co-morbid conditions reported more complications, whereas age, sex and socioeconomic status (adjusted for co-morbidity) had little, or no association. Complications were strongly associated with readmission and further surgery. Among patients reporting a complication, the Oxford Hip Score or Oxford Knee Score was about 3 points (or 15 per cent) lower than the value in patients not reporting a complication. The EQ-5D™ score was about 0·07 lower for joint replacement, 0·06 lower for hernia repair and 0·04 lower for varicose vein surgery.

Conclusion
Patients' reports of complications can be used for statistical comparisons of surgical departments. If the relationship between complications and health gain is causal, there is scope for improving health gain indicators after surgery by minimizing the risk of a complication.
Loss of the nerve monitoring signal during bilateral thyroid surgery
Authors: Dralle H , Sekulla C , Lorenz K , Thanh P Nguyen , Schneider R , Machens A 
Published: June 2012

Abstract

Background
This study aimed to assess current use of recurrent laryngeal nerve monitoring (RLNM) for bilateral thyroid surgery in Germany. It explored the willingness of surgeons to change strategy after loss of signal (LOS) on the first side of resection.

Methods
Surgical departments in Germany equipped with nerve monitors were asked to complete a structured questionnaire, specifying the number of thyroidectomies done in 2010, and the frequencies of RLNM, vagal stimulation, and electromyographic (EMG) recording before and after thyroidectomy. They were also asked about the surgical plan for bilateral goitre after LOS on the first side of resection.

Results
Based on manufacturers' sales data, 1119 (89·1 per cent) of 1256 surgical departments in Germany were equipped with nerve monitors in 2010. A total of 595 departments (53·2 per cent), accounting for approximately 75 per cent of all thyroidectomies in Germany during that year, returned a completed questionnaire. RLNM was used in 91·7–93·5 per cent of thyroidectomies, with the addition of routine vagal stimulation in 49·3 per cent before, and 73·8 per cent after resection. EMG responses to vagal stimulation were recorded in 54·8 per cent before, and 72·5 per cent after resection. Some 93·5 per cent of surgeons changed the resection plan for the other side in bilateral thyroid surgery after LOS had occurred on the first side.

Conclusion
RLNM is now the standard of care during thyroidectomy in Germany. After LOS on the first side of resection in bilateral goitre, more than 90 per cent of respondents declared their willingness to change the resection plan for the contralateral side to avoid the risk of bilateral recurrent laryngeal nerve palsy.
Polycyclic Polyprenylated Acylphloroglucinols and Cytotoxic Constituents of Hypericum androsaemum
Authors: Wang Kou , Wang Yuan‐Yuan , Gao Xiu , Chen Xuan‐Qin , Peng Li‐Yan , Li Yan , Xu Gang , Zhao Qin‐Shi 
Published: June 2012

AbstractTwo new polycyclic polyprenylated acylphloroglucinols (PPAPs), androforin A and hyperandrone A (1 and 2, resp.), together with twelve known compounds, were isolated from the aerial parts of Hypericum androsaemum. Their structures were established by detailed spectral analysis. In the cytotoxic assay, 1,4‐O‐diferuloylsecoisolariciresinol (3) showed activities comparable with those of cisplatin, and acetyloleanolic acid (4) exhibited moderate inhibitory effects against HL‐60, SMMC‐7721, A‐549, MCF‐7, and SW480 cancer cell lines.
Lavandulyl Flavanones from the Stems of Hypericum calycinum L.
Authors: Win Thida , Htwe Thant Thant , Shwe Htay Htay , Heilmann Jörg 
Published: June 2012

AbstractOne novel lavandulyl flavanone (=2,3‐dihydro‐2‐phenyl‐4H‐1‐benzopyran‐4‐one) with an unusual 5,2′,4′,6′‐tetrahydroxy substitution, calycinigin A (1), was isolated from the stems of Hypericum calycinum L. (Hypericaceae). The structure was elucidated on the basis of 1D‐ and 2D‐NMR analysis, as well as mass spectrometry (LR‐EI‐ and HR‐EI‐MS) and circular dichroism. Three known lavandulyl flavanones with 5,7,2′,4′,6′‐pentahydroxy substitution, i.e., 2–4, were also isolated. Chemosystematically, this is the first report on the occurrence of prenylated flavanones in the family Hypericaceae. Reduction of cell viability by all compounds was evaluated in a MTT (=3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide) assay using HeLa cells. Compound 1 showed moderate activity with an IC50 value of 9.7±1.8 μM, whereas compounds 2–4 were less active exhibiting IC50 values of 11.6±0.9, 19.3±1.5, and 40.7±2.4 μM, respectively. The antioxidant activity was evaluated by an ORAC (Oxygen Radical Absorbance Capacity) assay, and calycinigin A (1) was again the most active compound with a Trolox equivalent of 2.3±0.2. None of the compounds was able to reduce the TNF‐α induced ICAM‐1 expression in vitro using human microvascular endothelial cells (HMEC‐1).
New Bioactive Sulfated Alkenes from the Sea Cucumber Apostichopus japonicus
Authors: La Ming‐Ping , Li Cui , Li Ling , Sun Peng , Tang Hua , Liu Bao‐Shu , Gong Wei , Han Hua , Yi Yang‐Hua , Zhang Wen 
Published: June 2012

AbstractTwo new alkene sulfates, (5Z)‐dec‐5‐en‐1‐yl sulfate (4) and (3E)‐dec‐3‐en‐1‐yl sulfate (5), together with three known sulfated alkanes, 2,6‐dimethylheptyl sulfate (1), octyl sulfate (2), and decyl sulfate (3), were isolated from the sea cucumber Apostichopus japonicus. The structures of the new compounds 4 and 5 were elucidated by spectroscopic analysis, including 1H‐, 13C‐, and 2D‐NMR, ESI‐MS, and HR‐ESI‐MS. Compounds 2 and 3 were isolated from natural sources for the first time. In preliminary bioassays in vitro, compounds 4 and 5 showed antibacterial, antifungal, and cytotoxic activities.
Enhanced Interfacial Charge Transfer and Visible Photocatalytic Activity for Hydrogen Evolution from a Ta2O5‐based Mesoporous Composite by the Incorporation of Quantum‐Sized CdS
Authors: Xu Leilei , Guan Jianguo , Shi Weidong 
Published: June 2012

AbstractThe development of high‐performance visible‐light‐driven photocatalysts is attractive for the simultaneous achievement of sustainable hydrogen production and waste‐water treatment in an economical and large‐scale manner. An ordered mesoporous composite of quantum‐sized CdS (q‐CdS)/Ta2O5 with enhanced interfacial charge transfer was prepared by evaporation‐induced self‐assembly in the presence of a triblock‐copolymer surfactant followed by ion‐exchange treatment. The incorporation of cubic CdS into an amorphous Ta2O5 framework effectively extended its spectroscopic response from the ultraviolet into the visible region. The quantum‐confinement effect of CdS nanoparticles (3–4 nm) afforded an increased potential gradient between q‐CdS and Ta2O5, thereby accelerating the transfer of photogenerated electrons from q‐CdS to Ta2O5 and suppressing the recombination of charge carriers. Owing to this increased potential gradient and the large specific surface area, as well as the strong adsorption capability towards methylene blue (MB), the as‐prepared ordered mesoporous photocatalyst exhibited significantly enhanced visible‐light‐driven photocatalytic activity and long‐term stability for hydrogen evolution from simulant waste water that contained MB in the absence of any co‐catalysts. These results may have applications in the sustainable production of hydrogen energy and in environmental remediation.
Hierarchical Organization of Ferrocene–Peptides
Authors: Beheshti Samaneh , Martić Sanela , Kraatz Heinz‐Bernhard 
Published: June 2012

AbstractHierarchical self‐assembly of disubstituted ferrocene (Fc)–peptide conjugates that possess Gly‐Val‐Phe and Gly‐Val‐Phe‐Phe peptide substituents leads to the formation of nano‐ and micro‐sized assemblies. Hydrogen‐bonding and hydrophobic interactions provide directionality to the assembly patterns. The self‐assembling behavior of these compounds was studied in solution by using 1H NMR and circular dichroism (CD) spectroscopies. In the solid state, attenuated total reflectance (ATR) FTIR spectroscopy, single‐crystal X‐ray diffraction (XRD), powder X‐ray diffraction (PXRD), and scanning electron microscopy (SEM) methods were used. Spontaneous self‐assembly of Fc–peptides through intra‐ and intermolecular hydrogen‐bonding interactions induces supramolecular assemblies, which further associate and give rise to fibers, large fibrous crystals, and twisted ropes. In the case of Fc[CO‐Gly‐Val‐Phe‐OMe]2 (1), molecules initially interact to form pleated sheets that undergo association into long fibers that form bundles and rectangular crystalline cuboids. Molecular offsets and defects, such as screw dislocations and solvent effects that occur during crystal growth, induce the formation of helical arrangements, ultimately leading to large twisted ropes. By contrast, the Fc–tetrapeptide conjugate Fc[CO‐Gly‐Val‐Phe‐Phe‐OMe]2 (2) forms a network of nanofibers at the supramolecular level, presumably due to the additional hydrogen‐bonding and hydrophobic interactions that stem from the additional Phe residues.
Partially Reduced Graphite Oxide as an Electrode Material for Electrochemical Double‐Layer Capacitors
Authors: Hantel Moritz M. , Kaspar Tommy , Nesper Reinhard , Wokaun Alexander , Kötz Rüdiger 
Published: June 2012

AbstractPartially reduced graphite oxide was prepared from graphite oxide by using synthetic graphite as precursor. The reduction of graphite oxide with a layer distance of 0.57 nm resulted in a reduction of the layer distance depending on the degree of reduction. Simultaneously the amount of oxygen functionalities in the graphite oxide was reduced, which was corroborated by elemental analysis and EDX.The electrochemical activation of the partially reduced graphite oxide was investigated for tetraethylammonium tetrafluoroborate in acetonitrile and in propylene carbonate. The activation potential depends significantly on the degree of reduction, that is, on the graphene‐layer distance and on the solvent used. The activation potential decreased with increasing layer distance for both positive and negative activation.The resulting capacitance after activation was found to be affected by the layer distance, the oxygen functionalities and the used electrolyte. For a layer distance of 0.43 nm and with acetonitrile as the solvent, a differential capacitance of 220 Fg−1 was achieved for the discharge of the positive electrode near the open‐circuit potential and 195 Fg−1 in a symmetric full‐cell assembly.