bluuebunny/crossref_metadata_2025 huggingface dataset:
Primary Lymph Node Gastrinoma or Metastatic Gastrinoma with Unidentified Primary Tumor Site?
Authors: Martin Jack L , Tedeschi Michele , Jackson James E , Spalding Duncan , Goldstone Anthony P , Cohen Patrizia , Frilling Andrea
Published: August 2012

Gastrinomas are neuroendocrine tumors that secrete gastrin and result in a clinical syndrome of peptic ulcer disease first described by Zollinger and Ellison in 1955.1 They present either sporadically or as a component of a hereditary determined syndrome, multiple endocrine neoplasia type 1. They are usually located in the pancreas and duodenum but have been reported to occur in both abdominal and extraabdominal sites.2 Reports of clinical and biochemical cure following resection of lymph nodes found to contain gastrinomas, in patients without a localized primary tumor, led investigators to cite the existence of the primary lymph node gastrinoma. Whether these cases represent metastatic disease from an, as yet, unidentified primary tumor, or de novo occurrence of a gastrinoma in a lymph node remains controversial. While some authors report that primary lymph node gastrinomas account for up to 10% of sporadic gastrinomas3,4 others question this theory, hypothesizing that their presentation represents an undetected microgastrinoma with metastatic lymph node involvement.5

Herewith, we report on a patient with Zollinger-Ellison syndrome in whom a peripancreatic lymph node with evidence of gastrinoma is the only apparent morphologic manifestation of the disease.

How to cite this article

Martin JL, Tedeschi M, Jackson JE, Spalding D, Goldstone AP, Cohen P, Frilling A. Primary Lymph Node Gastrinoma or Metastatic Gastrinoma with Unidentified Primary Tumor Site? World J Endocr Surg 2012;4(2):66-70.
Extreme Tracheal Compression due to Substernal Goiter: Surgical and Anesthetic Management
Authors: Dy Benzon , Wise Kevin , Farley David , McGlinch Brian
Published: August 2012

Substernal goiters can have a range of presentations and pathology from a complete lack of symptoms to minimal biochemical abnormalities to potentially lethal physical derangements due to tracheal compression. We review a case of a substernal goiter with severe tracheal compression and airway compromise and describe the presentation, diagnosis, operative treatment, perianesthetic management and outcome of this patient. Substernal goiters can have a myriad of symptoms and etiologies. Once the diagnosis is secured, a multidisciplinary approach is key to successful management in the perioperative period.

How to cite this article

Dy B, Wise K, Farley D, McGlinch B. Extreme Tracheal Compression due to Substernal Goiter: Surgical and Anesthetic Management. World J Endocr Surg 2012;4(2):71-73.
Spindle Epithelial Tumor with Thymus-like Element of the Thyroid Gland
Authors: Satyanarayana V , Mote Dajiram Govonda
Published: August 2012

Spindle epithelial tumor with thymus-like different ion (SETTLE) is an extremely rare tumor arising from thyroid gland which was first time recognized and reported by Chan and Rosai. It is believed to be arising from the branchial pouch or the remnant of thymus within the thyroid gland as it reveals primitive thymic elements. It has been reported more than 20 times as an individual case reports in the searched English literature. It mostly occurs in the children and adolescent but cases of SETTLE are reported in adults and even in elderly patients. Age of patient is not diagnostic feature of the SETTLE tumor. According to the published data, SETTLE tumor has an indolent course but delayed blood-borne distant metastases is seen in the cases with long-term follow-up. The present case is 13-year-old boy who presented with solitary nodule of left lobe of the thyroid without any other symptoms. The patient was subjected to ipsilateral hemithyroidectomy. The histopathological report revealed the diagnosis of SETTLE tumor which was confirmed with the immunohistochemistry. The patient is followed-up regularly and there is no evidence of metastasis with more than 4 years follow-up. There are no existing guidelines regarding the optimum treatment and the duration of follow-up due to paucity of data about management of SETTLE tumor. The long-term follow-up is needed to detect recurrence or metastases.

How to cite this article

Mote DG, Satyanarayana V. Spindle Epithelial Tumor with Thymus-like Element of the Thyroid Gland. World J Endoc Surg 2012;4(2):74-76.
Circuit Theory Extended: The Role of Speculation in Crises
Authors: Lancastle Neil
Published: August 2012

This paper asks why modern finance theory and the efficient market hypothesis have failed to explain long-term carry trades; persistent asset bubbles or zero lower bounds; and financial crises. It extends Godley and Lavoie (Monetary Economics: An Integrated Approach to Credit, Money, Income, Production and Wealth, 2007) and the Theory of the Monetary Circuit to give a mathematical representation of Minsky’s Financial Instability Hypothesis. In the extended circuit, the central bank rate is not neutral and the path is nonergodic. The extended circuit has survival constraints that include a living wage, a zero interest rate and an upper interest rate. Inflation is everywhere. The possibility of stable carry trades emerges. In high interest rate, hedge economies, powerful banks invest surplus loan interest. With speculation, banks lobby to enter investment markets and the system is precariously liquid/illiquid. In a Ponzi economy, where loans never get repaid, solvency is a balance between increasing reserves, reducing interest rates and rebuilding banks’ balance sheets during systemic crises. Simulating bank bailouts, household bailouts and a Keynesian boost suggests that bank bailouts are the least effective intervention, exerting downward pressure on wages and household spending: austerity.
Reputational benefit of punishment: Comparison among the punisher, rewarder, and non-sanctioner
Authors: Ozono Hiroki , Watabe Motoki
Published: August 2012

Many researchers have suggested that a sanctioning system is necessary to achieve cooperation in a large society. Sanctioning others, however, is costly, raising the question of what exactly is the adaptive advantage of sanctioning. One possible answer is that sanctioners get reputational benefit. While the reputational benefits accruing to punishers and nonpunishers have been compared in previous studies, in the present study we directly compared the reputational benefit of punisher, rewarder, and non-sanctioner. We conducted a scenario experiment in which participants were asked to play several games, such as the Ultimatum Game, Dictator Game, and Chicken Game with punisher, rewarder, and non-sanctioner. While in previous studies, punishers have gotten better reputational benefit as providers of resources than have non-sanctioners, we found that punishers received worse reputations than did rewarders or non-sanctioners in all games used in our experiment. These results suggest that reputational benefits change according to what kind of sanction individuals can exercise.
Hydration or dehydration: competing effects of upper tropospheric cloud radiation on the TTL water vapor
Authors: Wu L. , Su H. , Jiang J. H. , Read W. G.
Published: August 2012

Abstract. A tropical channel version of the Weather Research and Forecasting (WRF) model is used to investigate the radiative impacts of upper tropospheric clouds on water vapor in the tropical tropopause layer (TTL). The WRF simulations of cloud radiative effects and water vapor in the upper troposphere and lower stratosphere show reasonable agreement with observations, including approximate reproduction of the water vapor "tape recorder" signal. By turning on and off the upper tropospheric cloud radiative effect (UTCRE) above 200 hPa, we find that UTCRE induces a warming of 0.76 K and a moistening of 9% in the upper troposphere at 215 hPa. However, UTCRE cools and dehydrates the TTL, with a cooling of 0.82 K and a dehydration of 16% at 100 hPa. The enhanced vertical ascent due to UTCRE contributes substantially to mass transport and the dehydration in the TTL. The hydration due to the enhanced vertical transport is counteracted by the dehydration from adiabatic cooling associated with the enhanced vertical motion. UTCRE also substantially changes the horizontal winds in the TTL, resulting in shifts of the strongest dehydration away from the lowest temperature anomalies in the TTL. UTCRE increases in-situ cloud formation in the TTL. A seasonal variation is shown in the simulated UTCRE, with stronger impact in the moist phase from June to November than in the dry phase from December to May.
Summertime photochemistry during CAREBeijing-2007: ROx budgets and O3 formation
Authors: Liu Z. , Wang Y. , Gu D. , Zhao C. , Huey L. G. , Stickel R. , Liao J. , Shao M. , Zhu T. , Zeng L. , Amoroso A. , Costabile F. , Chang C.-C. , Liu S.-C.
Published: August 2012

Abstract. We analyze summertime photochemistry near the surface in Beijing, China, using a 1-D photochemical model (Regional chEmical and trAnsport Model, REAM-1D) constrained by in situ observations, focusing on the budgets of ROx (OH + HO2 + RO2) radicals and O3 formation. While the modeling analysis focuses on near-surface photochemical budgets, the implications for the budget of O3 in the planetary boundary layer are also discussed. In terms of daytime average, the total ROx primary production rate near the surface in Beijing is 6.6 ppbv per hour (ppbv h−1, among the highest found in urban atmospheres. The largest primary ROx source in Beijing is photolysis of oxygenated volatile organic compounds (OVOCs), which produces HO2 and RO2 at 2.5 ppbv h−1 and 1.7 ppbv h−1, respectively. Photolysis of excess HONO from an unknown heterogeneous source is the predominant primary OH source at 2.2 ppbv h−1, much larger than that of O1D+H2O (0.4 ppbv h−1). The largest ROx sink is via OH + NO2 reaction (1.6 ppbv h−1), followed by formation of RO2NO2 (1.0 ppbv h−1) and RONO2 (0.7 ppbv h−1). Due to the large aerosol surface area, aerosol uptake of HO2 appears to be another important radical sink, although the estimate of its magnitude is highly variable depending on the uptake coefficient value used. The daytime average O3 production and loss rates near the surface are 32 ppbv h−1 and 6.2 ppbv h−1, respectively. Assuming NO2 to be the source of excess HONO, the NO2 to HONO transformation leads to considerable O3 loss and reduction of its lifetime. Our observation-constrained modeling analysis suggests that oxidation of VOCs (especially aromatics) and heterogeneous reactions (e.g. HONO formation and aerosol uptake HO2) play potentially critical roles in the primary radical budget and O3 formation in Beijing. One important ramification is that O3 production is neither NOx nor VOC limited, but in a transition regime where reduction of either NOx or VOCs could result in reduction of O3 production. The transition regime implies more flexibility in the O3 control strategies than a binary system of either NOx or VOC limited regime. The co-benefit of concurrent reduction of both NOx and VOCs in reducing column O3 production integrated in the planetary boundary layer is significant. Further research on the spatial extent of the transition regime over the polluted eastern China is critically important for controlling regional O3 pollution.
Observations of middle atmospheric H2O and O3 during the 2010 major sudden stratospheric warming by a network of microwave radiometers
Authors: Scheiben D. , Straub C. , Hocke K. , Forkman P. , Kämpfer N.
Published: August 2012

Abstract. In this study, we present middle atmospheric water vapor (H2O) and ozone (O3) measurements obtained by ground-based microwave radiometers at three European locations in Bern (47° N), Onsala (57° N) and Sodankylä (67° N) during Northern winter 2009/2010. In January 2010, a major sudden stratospheric warming (SSW) occurred in the Northern Hemisphere whose signatures are evident in the ground-based observations of H2O and O3. The observed anomalies in H2O and O3 are mostly explained by the relative location of the polar vortex with respect to the measurement locations. The SSW started on 26 January 2010 and was most pronounced by the end of January. The zonal mean temperature in the middle stratosphere (10 hPa) increased by approximately 25 Kelvin within a few days. The stratospheric vortex weakened during the SSW and shifted towards Europe. In the mesosphere, the vortex broke down, which lead to large scale mixing of polar and midlatitudinal air. After the warming, the polar vortex in the stratosphere split into two weaker vortices and in the mesosphere, a new, pole-centered vortex formed with maximum wind speed of 70 m s−1 at approximately 40° N. The shift of the stratospheric vortex towards Europe was observed in Bern as an increase in stratospheric H2O and a decrease in O3. The breakdown of the mesospheric vortex during the SSW was observed at Onsala and Sodankylä as a sudden increase in mesospheric H2O. The following large-scale descent inside the newly formed mesospheric vortex was well captured by the H2O observations in Sodankylä. In order to combine the H2O observations from the three different locations, we applied the trajectory mapping technique on our H2O observations to derive synoptic scale maps of the H2O distribution. Based on our observations and the 3-D wind field, this method allows determining the approximate development of the stratospheric and mesospheric polar vortex and demonstrates the potential of a network of ground-based instruments.
Cloud condensation nuclei production associated with atmospheric nucleation: a synthesis based on existing literature and new results
Authors: Kerminen V.-M. , Paramonov M. , Anttila T. , Riipinen I. , Fountoukis C. , Korhonen H. , Asmi E. , Laakso L. , Lihavainen H. , Swietlicki E. , Svenningsson B. , Asmi A. , Pandis S. N. , Kulmala M. , Petäjä T.
Published: August 2012

Abstract. This paper synthesizes the available scientific information connecting atmospheric nucleation with subsequent Cloud Condensation Nuclei (CCN) formation. We review both observations and model studies related to this topic, and discuss the potential climatic implications. We conclude that CCN production associated with atmospheric nucleation is both frequent and widespread phenomenon in many types of continental boundary layers, and probably also over a large fraction of the free troposphere. The contribution of nucleation to the global CCN budget spans a relatively large uncertainty range, which, together with our poor understanding of aerosol–cloud interactions, results in major uncertainties in the radiative forcing by atmospheric aerosols. In order to better quantify the role of atmospheric nucleation in CCN formation and Earth System behavior, more information is needed on (i) the factors controlling atmospheric CCN production and (ii) the properties of both primary and secondary CCN and their interconnections. In future investigations, more emphasis should be put on combining field measurements with regional and large-scale model studies.
Remote sensing of near-infrared chlorophyll fluorescence from space in scattering atmospheres: implications for its retrieval and interferences with atmospheric CO2 retrievals
Authors: Frankenberg C. , O'Dell C. , Guanter L. , McDuffie J.
Published: August 2012

Abstract. With the advent of dedicated greenhouse gas space-borne spectrometers sporting high resolution spectra in the O2 A-band spectral region (755–774 nm), the retrieval of chlorophyll fluorescence has become feasible on a global scale. If unaccounted for, however, fluorescence can indirectly perturb the greenhouse gas retrievals as it perturbs the oxygen absorption features. As atmospheric CO2 measurements are used to invert net fluxes at the land–atmosphere interface, a bias caused by fluorescence can be crucial as it will spatially correlate with the fluxes to be inverted. Avoiding a bias and retrieving fluorescence accurately will provide additional constraints on both the net and gross fluxes in the global carbon cycle. We show that chlorophyll fluorescence, if neglected, systematically interferes with full-physics multi-band XCO2 retrievals using the O2 A-band. Systematic biases in XCO2 can amount to +1 ppm if fluorescence constitutes 1% to the continuum level radiance. We show that this bias can be largely eliminated by simultaneously fitting fluorescence in a full-physics based retrieval. If fluorescence is the primary target, a dedicated but very simple retrieval based purely on Fraunhofer lines is shown to be more accurate and very robust even in the presence of large scattering optical depths. We find that about 80% of the surface fluorescence is retained at the top-of-atmosphere, even for cloud optical thicknesses around 2–5. We further show that small instrument modifications to future O2 A-band spectrometer spectral ranges can result in largely reduced random errors in chlorophyll fluorescence, paving the way towards a more dedicated instrument exploiting solar absorption features only.
Are drought occurrence and severity aggravating? A study on SPI drought class transitions using log-linear models and ANOVA-like inference
Authors: Moreira E. E. , Mexia J. T. , Pereira L. S.
Published: August 2012

Abstract. Long time series (95 to 135 yr) of the 12-month time scale Standardized Precipitation Index (SPI) relative to 10 locations across Portugal were studied with the aim of investigating if drought frequency and severity are changing through time. Considering four drought severity classes, time series of drought class transitions were computed and later divided into several sub-periods according to the length of SPI time series. Drought class transitions were calculated to form a 2-dimensional contingency table for each sub-period, which refer to the number of transitions among drought severity classes. Two-dimensional log-linear models were fitted to these contingency tables and an ANOVA-like inference was then performed in order to investigate differences relative to drought class transitions among those sub-periods, which were considered as treatments of only one factor. The application of ANOVA-like inference to these data allowed to compare the sub-periods in terms of probabilities of transition between drought classes, which were used to detect a possible trend in droughts frequency and severity. Results for a number of locations show some similarity between alternate sub-periods and differences between consecutive ones regarding the persistency of severe/extreme and sometimes moderate droughts. In global terms, results do not support the assumption of a trend for progressive aggravation of drought occurrence during the last century, but rather suggest the existence of long duration cycles.
On the Use and Abuse of Necessity in the Law of State Responsibility
Authors: Sloane Robert D.
Published: August 2012

Necessity,necessità,is Machiavelli’s guiding principle . . . that infringing the moral law is justified when it is necessary.

Thus is inaugurated the dualism of modern political culture, which simultaneously upholds absolute and relative standards of value. The modern state appeals to morality, to religion, and to natural law as the ideological foundation for its existence. At the same time it is prepared to infringe any or all of these in the interest of self-preservation.

—J. M. Coetzee

Recent jurisprudence in investment arbitration, almost all of which originated in disputes arising out of Argentina’s turn-of-the-century fiscal crisis, has raised difficult questions about the existence, nature, and advisability of necessity as a defense to state responsibility. The jurisprudence has contributed to a sophisticated literature focusing on necessity’s role in the special context of investment arbitration. But the growing prominence of necessity pleas in international law has not been so limited. Nor will its effects be. In the first place, investor-state arbitral jurisprudence contributes to the evolution of general international law. Investment tribunals invoke the latter, for example, to inform their interpretation of bilateral investment treaties (BITs) or to cure lacunae in the law. More significantly, beyond the realm of investment arbitration, the past few decades have seen a striking growth in necessity pleas in fields ranging widely across the landscape of international law.
Attorney General Bradford’s Opinion and the Alien Tort Statute
Authors: Bradley Curtis A.
Published: August 2012

In debates over the scope of the Alien Tort Statute (ATS), one historical document has played an especially prominent role. That document is a short opinion by U.S. Attorney General William Bradford, issued in the summer of 1795, concerning the involvement of U.S. citizens in an attack by a French fleet on a British colony in Sierra Leone. In the opinion, Bradford concluded that “[s]o far ... as the transactions complained of originated or took place in a foreign country, they are not within the cognizance of our courts; nor can the actors be legally prosecuted or punished for them by the United States.” He also expressed the view that the actors could be prosecuted for crimes on the high seas, while noting that “some doubt rests on this point” in light of the language of the relevant criminal statute. Finally, he stated—in an obvious reference to the ATS—that

there can be no doubt that the company or individuals who have been injured by these acts of hostility have a remedy by acivilsuit in the courts of the United States; jurisdiction being expressly given to these courts in all cases where an alien sues for a tort only, in violation of the laws of nations, or a treaty of the United States . . . .

The Bradford opinion contains one of the few early historical references to the ATS, so it not surprisingly has received a lot of attention. Numerous academic articles, judicial opinions, and litigation briefs have invoked the Bradford opinion, for a variety of propositions. Reliance on the opinion has increased since the Supreme Court’s 2004 decision inSosa v. Alvarez-Machain, in which the Court cited the opinion in support of the proposition that the ATS provides jurisdiction over certain common law causes of action derived from the law of nations. As an illustration of its perceived significance, both sides discussed the opinion in the oral argument before the Supreme Court in the first hearing in the pending ATS case,Kiobel v. Royal Dutch Petroleum Co.
Are We Contributing to Our Students' Mistakes?
Authors: Kalder Robin S.
Published: August 2012

Teachers who have been in the classroom for a while know that year after year we see students make the same mistakes that previous students made. To prevent these errors, we try a variety of techniques, but it seems that no matter what we do, they reappear in students' work time and time again. Are we, despite our best efforts, contributing to these mistakes? I believe that we do, indeed, use some practices that inadvertently undermine our best intentions.
Making Hay While the Pancakes Cook
Authors: Corica Tim
Published: August 2012

Students analyze a photograph to solve mathematical questions related to the images captured in the photograph. This month, the mathematics is packing circles inside circles.
Three-Dimensional Printing: A Journey in Visualization
Authors: Poetzel Adam , Muskin Joseph , Munroe Anne , Russell Craig
Published: August 2012

Using simple materials, a Mathematica software application, and their knowledge of function transformations, students design and create real mathematical sculptures.
Fielding an After-School Mathematics Lab
Authors: Punches-Guntsch Christina M. , Kenney Erin N.
Published: August 2012

Teachers in an urban high school design a learning environment for at-risk mathematics students.
Physicochemical Peculiarities of Iodine-Dimethylsulfoxide-H2O Solutions and Effect on Ion Binding to Bovine Serum Albumin
Authors: Grigoryan K. , Shilajyan H.
Published: August 2012

The interaction of iodine with bovine serum albumin (BSA) in dimethylsulfoxide (DMSO) aqueous solutions was studied by means of fluorescence and UV/Vis absorption spectroscopy methods. Physicochemical peculiarities of these solutions were revealed. The results showed that the tri-iodide ion formed in the 1DMSO : 2H2O solution caused the fluorescence quenching of BSA. The modified Stern-Volmer quenching constant and corresponding thermodynamic parameters, the free energy change (), enthalpy change (), and entropy change (), at different temperatures (293, 298, and 303 K) were calculated, which indicated that the hydrophobic and electrostatic interactions were the predominant operating forces. The binding locality distance r between BSA and tri-iodide ion at different temperatures was determined based on Förster nonradiation fluorescence energy transfer theory.
Evaluating Wheat Microsatellite Markers for the Use in Genetic Analysis ofThinopyrum, Dasypyrum,andPseudoroegneriaSpecies
Authors: Kroupin Pavel Yu. , Divashuk Mikhail G. , Fesenko Igor A. , Karlov Gennady I.
Published: August 2012

A set of 42 SSRs of wheat were evaluated for their cross-amplification on the DNA ofThinopyrum ponticum, Thinopyrum intermedium, Thinopyrum elongatum, Thinopyrum bessarabicum, Pseudoroegneria stipifolia,andDasypyrum villosum.The number of the wheat SSR markers that amplified DNA fragments with determined size forTh. ponticumwas 33 (78.6%); forTh. intermedium,28 (66.7%); forTh. elongatum,24 (57.1%); forTh. bessarabicum,24 (57.1%); forP. stipifolia,26 (69.1%); and forD. villosum,29 (69.0%). Twenty-four primer pairs of wheat SSR markers were successfully amplified from all investigated species. The dataset can be used for phylogenetic studies of wild relatives of wheat, for the estimation of their diversity, and for the introgression of agronomically valuable genes into wheat genome.
Utility of colposcopy in a phase 2 portion of a microbicide clinical trial of BufferGel and 0.5% PRO 2000 Gel
Authors: Chirenje Zvavahera M , Mâsse Benoît R , Maslankowski Lisa A , Ramjee Gita , Coletti Anne S , Tembo Tchangani N , Magure Tsitsi M , Soto‐Torres Lydia , Kelly Cliff , Hillier Sharon , Karim Abdool
Published: August 2012

Background

The majority of new HIV infections are acquired through heterosexual transmission. There is urgent need for prevention methods to compliment behavior change and condom use. Topical microbicide represent a potential strategy for reduction of HIV transmission in women.

Methods

Monthly Colposcopy evaluations were performed during pelvic examinations among 299 women enrolled in the Phase 2 portion of HPTN 035 study at four sites (1 in USA, 3 in Southern Africa). This was a phase 2/2b, multisite, randomized, and controlled clinical trial with four arms: BufferGel, 0.5% PRO2000 Gel, placebo gel and no gel. At two of the sites, pelvic examinations were conducted by the use of naked eye without colposcopy.

Results

A colposcopy finding of any kind was detected in 48% of participants at baseline compared to 40% at 3 months (p =0.04). The lower rates were also observed in vaginal discharge (22% at baseline, 16% at 3 months, p=0.06), erythema (15% at baseline, 8% at 3 months, p=0.004). The trend towards significance at p=0.05 disappear when utilizing stringent statistical significance levels. A pelvic finding of any kind was detected in 71% of colposcopy participants compared to 41% of participants who had naked eye examination only conducted at two sites that performed both colposcopy and naked eye without colposcopy. Use of colposcopy yielded significantly higher rates of participants with deep epithelial disruption, erythema and ecchymosis. We observed no cases of incident Chlamydia, Gonorrhea, or Syphilis during the three month follow up. There were 2 cases of incident HIV during 3‐month study period neither of which was associated with any abnormal colposcopy evaluation findings.

Conclusion

No safety signals were observed in the 4 study arms, allowing seamless transition from phase 2 to 2b. Colposcopy utility in microbicide clinical trials has minimal value given high rates of background noise findings of no relevant clinical significance.
Controlling Interconnected Silver Network Structure in Sol–Gel Nanocomposite Via Shrinkage‐Induced Stress
Authors: Chiu Chi‐Kai , Chen Tsan‐Yao , Luo Tzy‐Jiun M.
Published: August 2012

An interconnected silver network composed of grain boundary layers with each layer about 100 nm thick was spontaneously formed inside a silica matrix when a sol–gel sample containing silver ion and polyethylene glycol was dried and heat‐treated. The minimum spacing of the silver structure was ≈15 µm and the density of the silver structure was related to the drying rate, which can be controlled by either drying temperature or vacuum drying time. It was found that the shrinkage‐induced stress during the drying process results in microcracks where the crack surfaces serve as a 3D template for silver to develop into interconnected network when the sample is annealed at 160 °C. The ability to control the density of microcracks and to utilize the microcracks as silver template suggests that this method can be utilized to (1) create interconnected silver network of desired density in silica materials, (2) visualize the microcracks of sol–gel materials, and (3) reinforce and repair the defects after microcracks have formed.
Energy Upconversion via Triplet Fusion in Super Yellow PPV Films Doped with Palladium Tetraphenyltetrabenzoporphyrin: a Comprehensive Investigation of Exciton Dynamics
Authors: Jankus Vygintas , Snedden Edward W. , Bright Daniel W. , Whittle Victoria L. , Williams J. A. G. , Monkman Andy
Published: August 2012

One of the key issues concerning the development of efficient polymer solar cell technology is the lack of viable materials which absorb in the near‐infrared (NIR) region. This could be resolved by up‐converting energy from the NIR into visible using triplet fusion (TF) with an additional layer that is fabricated separately from the solar cell and deposited on top. Theoretically a maximum upconversion (UC) via TF efficiency of 50% could be obtained. Here, it is demonstrated that in a film of commercially available poly(para‐phenylene vinylene) copolymer “super yellow” (SY) doped with 4% palladium(meso‐tetraphenyl‐tetrabenzoporphyrin) (PdTPBP) sensitizer, an UC efficiency of 6% can be achieved. By using femtosecond and nanosecond spectroscopies it is shown that the main UC efficiency loss mechanism is due to triplet quenching in PdTPBP aggregates. The PdTPBP intersystem crossing rate constant is determined to be 1.8 × 1011 s−1 and the triplet energy transfer rate constant from PdTPBP to SY to be 109 s−1. Quenching in PdTPBP aggregates can account for a triplet concentration loss in the range of 76‐99%. As such, preventing sensitizer aggregation in NIR‐to‐visible upconverting films is crucial and may lead to substantial increase of UC efficiencies in films.
Vertically Segregated Structure and Properties of Small Molecule–Polymer Blend Semiconductors for Organic Thin‐Film Transistors
Authors: Shin Nayool , Kang Jihoon , Richter Lee J. , Prabhu Vivek M. , Kline R. Joseph , Fischer Daniel A. , DeLongchamp Dean M. , Toney Michael F. , Satija Sushil K. , Gundlach David J. , Purushothaman Balaji , Anthony John E. , Yoon Do Y.
Published: August 2012

A comprehensive structure and performance study of thin blend films of the small‐molecule semiconductor, 2,8‐difluoro‐5,11‐bis(triethylsilylethynyl)anthradithiophene (diF‐TESADT), with various insulating binder polymers in organic thin‐film transistors is reported. The vertically segregated composition profile and nanostructure in the blend films are characterized by a combination of complementary experimental methods including grazing incidence X‐ray diffraction, neutron reflectivity, variable angle spectroscopic ellipsometry, and near edge X‐ray absorption fine structure spectroscopy. Three polymer binders are considered: atactic poly(α‐methylstyrene), atactic poly(methylmethacrylate), and syndiotactic polystyrene. The choice of polymer can strongly affect the vertical composition profile and the extent of crystalline order in blend films due to the competing effects of confinement entropy, interaction energy with substrate surfaces, and solidification kinetics. The variations in the vertically segregated composition profile and crystalline order in thin blend films explain the significant impacts of binder polymer choice on the charge carrier mobility of these films in the solution‐processed bottom‐gate/bottom‐contact thin‐film transistors.
Solid State Enabled Reversible Four Electron Storage
Authors: Yersak Thomas A. , Macpherson H. Alex , Kim Seul Cham , Le Viet‐Duc , Kang Chan Soon , Son Seoung‐Bum , Kim Yong‐Hyun , Trevey James E. , Oh Kyu Hwan , Stoldt Conrad , Lee Se‐Hee
Published: August 2012

We report that a solid‐state battery architecture enables the reversible, four electron storage of fully utilized solvothermally synthesized cubic‐FeS2 (pyrite). With a sulfide based glass electrolyte we successfully confine electro‐active species and permit the safe use of a lithium metal anode. These FeS2/Li solid‐state cells deliver a theoretical specific capacity of 894 mAh g−1 at 60 °C. We find that nanoparticles of orthorhombic‐FeS2 (marcasite) are generated upon recharge at 30–60 °C which explains a coincident change in rate kinetics.
Computed intranasal spray penetration: comparisons before and after nasal surgery
Authors: Frank Dennis O. , Kimbell Julia S. , Cannon Daniel , Rhee John S.
Published: August 2012

Background:

Quantitative methods for comparing intranasal drug delivery efficiencies pre‐ and postoperatively have not been fully utilized. The objective of this study is to use computational fluid dynamics techniques to evaluate aqueous nasal spray penetration efficiencies before and after surgical correction of intranasal anatomic deformities.

Methods:

Ten three‐dimensional models of the nasal cavities were created from pre‐ and postoperative computed tomography scans in 5 subjects. Spray simulations were conducted using a particle size distribution ranging from 10 μm to 110 μm, a spray speed of 3 m/second, plume angle of 68 degrees, and with steady state, resting inspiratory airflow present. Two different nozzle positions were compared. Statistical analysis was conducted using Student t test for matched pairs.

Results:

On the obstructed side, posterior particle deposition after surgery increased by 118% and was statistically significant (p = 0.036), while anterior particle deposition decreased by 13% and was also statistically significant (p = 0.020). The fraction of particles that bypassed the airways either pre‐ or postoperatively was less than 5%. Posterior particle deposition differences between obstructed and contralateral sides of the airways were 113% and 30% for pre‐ and postsurgery, respectively. Results showed that nozzle positions can influence spray delivery.

Conclusion:

Simulations predicted that surgical correction of nasal anatomic deformities can improve spray penetration to areas where medications can have greater effect. Particle deposition patterns between both sides of the airways are more evenly distributed after surgery. These findings suggest that correcting anatomic deformities may improve intranasal medication delivery. For enhanced particle penetration, patients with nasal deformities may explore different nozzle positions. © 2013 ARS–AAOA, LLC.
A novel sinonasal endoscopy scoring system: the discharge, inflammation, and polyps/edema (DIP) score
Authors: Durr Megan L. , Pletcher Steven D. , Goldberg Andrew N. , Murr Andrew H.
Published: August 2012

Background:

There is an increasing need for a validated grading system to assess sinusitis severity as observed on endoscopic examination. Existing endoscopy scales have limitations in complexity, validation, and/or applicability. We present a novel and straightforward endoscopic scoring system measuring discharge, inflammation, and polyps/edema (DIP). The aim of this study is to determine correlation of the DIP score with existing sinus endoscopy scoring systems, and to determine interrater and test‐retest reliability.

Methods:

This retrospective cohort includes a total of 29 patients who underwent functional endoscopic sinus surgery (FESS) for chronic rhinosinusitis. Sinus endoscopy videos were scored in a random and blinded fashion by 3 rhinologists (S.D.P., A.N.G., A.H.M.) using the Lund‐Kennedy Endoscopic Score (LKES), the Perioperative Sinus Endoscopy (POSE) score, and the DIP score. Pearson correlation coefficients, interrater reliability and test‐retest reliability were determined.

Results:

The results of this study show that the DIP score correlates well (p < 0.0001) with the existing LKES and POSE (Pearson correlation coefficients of 0.78 and 0.90, respectively). The interrater reliability intraclass correlation coefficient (ICC) is highest for the DIP score (0.87), followed by the POSE score (0.84) and the LKES (0.78). Test‐retest reliability ICC is highest for the DIP score (0.78), followed by the POSE score (0.59) and the LKES (0.53).

Conclusion:

The DIP score is a novel and straightforward endoscopic sinus scoring system that shows substantial test‐retest and interrater reliability in the post‐FESS population. It also demonstrates a high correlation with existing scoring parameters (LKES and POSE). © 2013 ARS–AAOA, LLC.
Opp‐Dibenzoporphyrins as a Light‐Harvester for Dye‐Sensitized Solar Cells
Authors: Deshpande Rohit , Wang Bo , Dai Lin , Jiang Lin , Hartley C. Scott , Zou Shouzhong , Wang Hong , Kerr Lei
Published: August 2012

New opp‐dibenzoporphyrins were prepared in a concise method that was based on a Pd0‐catalyzed cascade reaction. These porphyrins, which contained carboxylic‐acid linker groups on benzene rings that were fused to the porphyrin at their β,β′‐positions, were examined as sensitizers for dye‐sensitized solar cells for the first time. Whereas all of the porphyrins showed solar‐energy‐to‐electricity conversion, an opp‐dibenzoporphyrin with conjugated carboxylic‐acid linkers displayed the highest conversion efficiency and an exceptionally high Jsc value. Cyclic voltammetry of these porphyrins suggested that the fusion of two aromatic benzene rings onto the periphery of the porphyrin lowered the HOMO–LUMO energy gap; the incorporation of a conjugated carboxylic‐acid linker group decreased the HOMO–LUMO gap even further. These CV data are consistent with DFT calculations for these porphyrins and agree well with the UV/Vis absorption‐ and fluorescence spectra of these porphyrins.
Preparation and Catalysis of Carbon‐Supported Iron Catalysts for Fischer–Tropsch Synthesis
Authors: Sun Bo , Xu Ke , Nguyen Luan , Qiao Minghua , Tao Franklin (Feng)
Published: August 2012

Fischer–Tropsch synthesis (FTS) is essential for the transformation of natural gas, coal, and biomass to clean transportation fuels and value‐added chemicals. Traditionally, iron catalysts for FTS are predominantly fused iron catalysts and precipitated iron catalysts using silica as the support. Owing to an intense surge in interest in carbon materials during recent years, along with the unique properties of these materials, such as high surface area, high porosity, and ample structures, carbon‐supported iron‐based FTS catalysts have attracted increasing attention. In this detailed review of the progress of the Fe/C catalysts for FTS in the last three decades, particular emphasis is put on their preparation, characterization, and catalytic performance relevant to the characteristics of carbon materials. This review is intended to be a valuable resource to researchers interested in this exciting field of catalysis, as well as the foundation for those investigating applications of novel carbon materials. A brief discussion is also devoted to the challenges and opportunities regarding the future development of Fe/C FTS catalysts.
Solvent‐free Liquid‐phase Oxidation of 1‐Hexene using Supported Gold Catalysts
Authors: Alshammari Hamed , Miedziak Peter J. , Bawaked Salem , Knight David W. , Hutchings Graham J.
Published: August 2012

We report the solvent‐free oxidation of 1‐hexene with air by using supported gold catalysts with a catalytic amount of tert‐butyl hydroperoxide (TBHP) as initiator. We confirm that gold supported on graphite is an effective catalyst for such oxidations and that graphite was the preferred support. Preparation of catalysts using modified sol‐immobilisation was found to be effective, particularly when the PVA stabiliser was removed by a solvent treatment prior to the reaction.
Hybrid Polyoxotungstates as Functional Comonomers in New Cross‐Linked Catalytic Polymers for Sustainable Oxidation with Hydrogen Peroxide
Authors: Carraro Mauro , Fiorani Giulia , Mognon Lorenzo , Caneva Francesca , Gardan Martino , Maccato Chiara , Bonchio Marcella
Published: August 2012

Anchoring terminal octenyl tails on molecular polyoxotungstates yield polymerizable organic–inorganic monomers with formula [{CH2CH(CH2)6Si}xOySiWwOz]4−[x=2,w=11,y=1,z=39 (1);x=2,w=10,y=1,z=36 (2); andx=4,w=9,y=3,z=34 (3)]. These molecular hybrids can use aqueous hydrogen peroxide to catalyze the selective oxidation of organic sulfides in CH3CN. Copolymerization of1–3with methyl methacrylate and ethylene glycol dimethacrylate leads to porous materials with a homogeneous distribution of the functional monomers, as indicated by converging evidence from FTIR spectroscopy and electronic microscopy. The catalytic polymers activate hydrogen peroxide for oxygen transfer, as demonstrated by the quantitative and selective oxidation of methylp‐tolyl sulfide, which was screened as model substrate. The hybrid material containing monomer2was also tested inn‐octane to evaluate its potential for the oxidation and removal of dibenzothiophene, a well‐known gasoline contaminant.
Enantioselective Organocatalytic One‐Pot Amination/aza‐Michael/Aldol Condensation Reaction Sequence: Synthesis of 3‐Pyrrolines with a Quaternary Stereocenter
Authors: Desmarchelier Alaric , Coeffard Vincent , Moreau Xavier , Greck Christine
Published: August 2012

Primary amine‐catalyzed direct conversion of α,α‐disubstituted aldehydes into 3‐pyrrolines with a quaternary stereocenter is reported. The one‐pot enantioselective sequence is based on a α‐amination, an aza‐Michael addition of hydrazine, an aldol condensation dehydratation and proceeds with good yields and excellent levels of enantioselectivity. Synthetically attractive applications including the formation of aziridinopyrrolidine or epoxypyrrolidine derivatives with good yields and selectivities are also described.
MT1‐Selective Melatonin Receptor Ligands: Synthesis, Pharmacological Evaluation, and Molecular Dynamics Investigation of N‐{[(3‐O‐Substituted)anilino]alkyl}amides
Authors: Rivara Silvia , Pala Daniele , Lodola Alessio , Mor Marco , Lucini Valeria , Dugnani Silvana , Scaglione Francesco , Bedini Annalida , Lucarini Simone , Tarzia Giorgio , Spadoni Gilberto
Published: August 2012

The design of compounds selective for the MT1 melatonin receptor is still a challenging task owing to the limited knowledge of the structural features conferring selectivity for the MT1 subtype, and only few selective compounds have been reported so far. N‐(Anilinoalkyl)amides are a versatile class of melatonin receptor ligands that include nonselective MT1/MT2 agonists and MT2‐selective antagonists. We synthesized a new series of N‐(anilinoalkyl)amides bearing 3‐arylalkyloxy or 3‐alkyloxy substituents at the aniline ring, looking for new potent and MT1‐selective ligands. To evaluate the effect of substituent size and shape on binding affinity and intrinsic activity, both flexible and conformationally constrained derivatives were prepared. The phenylbutyloxy substituent gave the best result, providing the partial agonist 4 a, which was endowed with high MT1 binding affinity (pKi=8.93) and 78‐fold selectivity for the MT1 receptor. To investigate the molecular basis for agonist recognition, and to explain the role of the 3‐arylalkyloxy substituent, we built a homology model of the MT1 receptor based on the β2 adrenergic receptor crystal structure in its activated state. A binding mode for MT1 agonists is proposed, as well as a hypothesis regarding the receptor structural features responsible for MT1 selectivity of compounds with lipophilic arylalkyloxy substituents.
Asymmetric 4‐Aryl‐1,4‐dihydropyridines Potentiate Mutant Cystic Fibrosis Transmembrane Conductance Regulator (CFTR)
Authors: Giampieri Michele , Vanthuyne Nicolas , Nieddu Erika , Mazzei Marco T. , Anzaldi Maria , Pedemonte Nicoletta , Galietta Luis J. V. , Roussel Christian , Mazzei Mauro
Published: August 2012

Some of the genetic mutations that cause cystic fibrosis (CF) impair the gating of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl− ion channel. This defect can be corrected with pharmacological tools (potentiators) that belong to various chemical families, including the 1,4‐dihydropyridines (DHPs). A small set of asymmetric 4‐aryl‐DHPs was synthesized, and each racemic couple was tested in a functional assay carried out on cells expressing the G1349D, ΔF508, and G551D mutants. The most active racemates were subjected to chiral separation by HPLC, and the pure enantiomers were tested to evaluate any gains in activity. Although three enantiomers demonstrated high potency (Kd values less than 0.09, 0.1, and 0.5 μM in G1349D, ΔF508, and G551D, respectively), in general, the screening of pure enantiomers did not produce a great diversity in potency values. It is probable that the degree of DHP asymmetry considered in our analysis is still insufficient with respect to that allowed in a putative DHP binding site in CFTR, so that the site could equally accommodate both enantiomers.
Photocatalytic and Photoelectrochemical Water Oxidation over Metal‐Doped Monoclinic BiVO4 Photoanodes
Authors: Parmar Kanak Pal Singh , Kang Hyun Joon , Bist Amita , Dua Piyush , Jang Jum Suk , Lee Jae Sung
Published: August 2012

The visible‐light‐induced water oxidation ability of metal‐ion‐doped BiVO4 was investigated and of 12 metal ion dopants tested, only W and Mo dramatically enhanced the water photo‐oxidation activity of bare BiVO4; Mo had the highest improvement by a factor of about six. Thus, BiVO4 and W‐ or Mo‐doped (2 atom %) BiVO4 photoanodes about 1 μm thick were fabricated onto transparent conducting substrate by a metal–organic decomposition/spin‐coating method. Under simulated one sun (air mass 1.5G, 100 mW cm−2) and at 1.23 V versus a reversible hydrogen electrode, the highest photocurrent density (JPH) of about 2.38 mA cm−2 was achieved for Mo doping followed by W doping (JPH≈1.98 mA cm−2), whereas undoped BiVO4 gave a JPH value of about 0.42 mA cm−2. The photoelectrochemical water oxidation activity of W‐ and Mo‐doped BiVO4 photoanodes corresponded to the incident photon to current conversion efficiency of about 35 and 40 % respectively. Electrochemical impedance spectroscopy and Mott–Schottky analysis indicated a positive flat band shift of about 30 mV, a carrier concentration 1.6–2 times higher, and a charge‐transfer resistance reduced by 3–4‐fold for W‐ or Mo‐doped BiVO4 relative to undoped BiVO4. Electronic structure calculations revealed that both W and Mo were shallow donors and Mo doping generated superior conductivity to W doping. The photo‐oxidation activity of water on BiVO4 photoanodes (undoped<W doped<Mo doped) was in accordance with the results from electrochemical impedance spectroscopy, Mott–Schottky analysis, and theoretical electronic structural calculations. Thus, Mo or W doping enhanced the photocatalytic and photoelectrochemical water oxidation activity of monoclinic BiVO4 by drastically reducing its charge‐transfer resistance and thereby minimizing photoexcited electron–hole pair recombination.