bluuebunny/crossref_metadata_2025 huggingface dataset:
Secondary organic aerosol formation from biomass burning intermediates: phenol and methoxyphenols
Authors: Yee L. D. , Kautzman K. E. , Loza C. L. , Schilling K. A. , Coggon M. M. , Chhabra P. S. , Chan M. N. , Chan A. W. H. , Hersey S. P. , Crounse J. D. , Wennberg P. O. , Flagan R. C. , Seinfeld J. H.
Published: February 2013

Abstract. The formation of secondary organic aerosol from oxidation of phenol, guaiacol (2-methoxyphenol), and syringol (2,6-dimethoxyphenol), major components of biomass burning, is described. Photooxidation experiments were conducted in the Caltech laboratory chambers under low-NOx (<10 ppb) conditions using H2O2 as the OH source. Secondary organic aerosol (SOA) yields (ratio of mass of SOA formed to mass of primary organic reacted) greater than 25% are observed. Aerosol growth is rapid and linear with the primary organic conversion, consistent with the formation of essentially non-volatile products. Gas- and aerosol-phase oxidation products from the guaiacol system provide insight into the chemical mechanisms responsible for SOA formation. Syringol SOA yields are lower than those of phenol and guaiacol, likely due to novel methoxy group chemistry that leads to early fragmentation in the gas-phase photooxidation. Atomic oxygen to carbon (O:C) ratios calculated from high-resolution-time-of-flight Aerodyne Aerosol Mass Spectrometer (HR-ToF-AMS) measurements of the SOA in all three systems are ~0.9, which represent among the highest such ratios achieved in laboratory chamber experiments and are similar to that of aged atmospheric organic aerosol. The global contribution of SOA from intermediate volatility and semivolatile organic compounds has been shown to be substantial (Pye and Seinfeld, 2010). An approach to representing SOA formation from biomass burning emissions in atmospheric models could involve one or more surrogate species for which aerosol formation under well-controlled conditions has been quantified. The present work provides data for such an approach.
Validation of middle atmospheric campaign-based water vapour measured by the ground-based microwave radiometer MIAWARA-C
Authors: Tschanz B. , Straub C. , Scheiben D. , Walker K. A. , Stiller G. P. , Kämpfer N.
Published: February 2013

Abstract. Middle atmospheric water vapour can be used as a tracer for dynamical processes. It is mainly measured by satellite instruments and ground-based microwave radiometers. Ground-based instruments capable of measuring middle atmospheric water vapour are sparse but valuable as they complement satellite measurements, are relatively easy to maintain and have a long lifetime. MIAWARA-C is a ground-based microwave radiometer for middle atmospheric water vapour designed for use on measurement campaigns for both atmospheric case studies and instrument intercomparisons. MIAWARA-C's retrieval version 1.1 (v1.1) is set up in a way to provide a consistent data set even if the instrument is operated from different locations on a campaign basis. The sensitive altitude range for v1.1 extends from 4 hPa (37 km) to 0.017 hPa (75 km). MIAWARA-C measures two polarisations of the incident radiation in separate receiver channels and can therefore provide two independent measurements of the same air mass. The standard deviation of the difference between the profiles obtained from the two polarisations is in excellent agreement with the estimated random error of v1.1. In this paper, the quality of v1.1 data is assessed during two measurement campaigns: (1) five months of measurements in the Arctic (Sodankylä, 67.37° N/26.63° E) and (2) nine months of measurements at mid-latitudes (Zimmerwald, 46.88° N/7.46° E). For both campaigns MIAWARA-C's profiles are compared to measurements from the satellite experiments Aura MLS and MIPAS. In addition, comparisons to ACE-FTS and SOFIE are presented for the Arctic and to the ground-based radiometer MIAWARA for the mid-latitudinal campaign. In general all intercomparisons show high correlation coefficients, above 0.5 at altitudes above 45 km, confirming the ability of MIAWARA-C to monitor temporal variations on the order of days. The biases are generally below 10% and within the estimated systematic uncertainty of MIAWARA-C. No consistent wet or dry bias is identified for MIAWARA-C. In addition, comparisons to the reference instruments indicate the estimated random error of v1.1 to be a realistic measure of the random variation on the retrieved profile.
Hortonian overland flow closure relations in the Representative Elementary Watershed Framework evaluated with observations
Authors: Vannametee E. , Karssenberg D. , Hendriks M. R. , Bierkens M. F. P.
Published: February 2013

Abstract. This paper presents an evaluation of the closure relation for Hortonian runoff that explicitly accounts for sub-REW process heterogeneity and scale effects, proposed in Vannametee et al. (2012). We apply the closure relation, which is embedded in an event-based rainfall-runoff model developed under the REW framework, to a 15 km2 catchment in the French Alps. The scaling parameters in the closure relation are directly estimated using local and thus observable REW properties and rainstorm characteristics. Evaluation of the simulation results against the observed discharge indicates good performance in reproducing the hydrograph and discharge volume, even without calibration. The discharge prediction exhibits a significant improvement when the closure relation is calibrated with catchment-scale runoff. Our closure relation also yields better predictions when compared with results from a benchmark closure relation that does not consider scale effects. Calibration is done by only changing one of the REW observables, i.e. hydraulic conductivity, as that determines the scaling parameters, using a single prefactor for the entire catchment. This enables the calibration of the (semi)distributed modelling framework in this study to use only a single parameter. The results without calibration suggest that, in the absence of discharge observations, reasonable estimates of catchment-scale runoff responses are possibly based on observations at the sub-REW (i.e. plot) scale. Thus, our study provides a platform for the future development of low-dimensional and robust semi-distributed, physically-based discharge models in ungauged catchments.
Characterization of turbulence stability through the identification of multifractional Brownian motions
Authors: Lee K. C.
Published: February 2013

Abstract. Multifractional Brownian motions have become popular as flexible models in describing real-life signals of high-frequency features in geoscience, microeconomics, and turbulence, to name a few. The time-changing Hurst exponent, which describes regularity levels depending on time measurements, and variance, which relates to an energy level, are two parameters that characterize multifractional Brownian motions. This research suggests a combined method of estimating the time-changing Hurst exponent and variance using the local variation of sampled paths of signals. The method consists of two phases: initially estimating global variance and then accurately estimating the time-changing Hurst exponent. A simulation study shows its performance in estimation of the parameters. The proposed method is applied to characterization of atmospheric stability in which descriptive statistics from the estimated time-changing Hurst exponent and variance classify stable atmosphere flows from unstable ones.
An Incomplete Block Change-Over Design Balanced for First and Second-Order Residual Effect
Authors: Chowdhury Kanchan , Rois Rumana
Published: February 2013

Balanced designs are often needed in agriculture, economics and other context. A series of balanced designs called incomplete block change-over design (IBCOD) has been developed. The analysis and the problems of IBCOD which also provide estimates of first-order and second-order residual effects have also been presented.
Introduzione di una Checklist per Ridurre Gli Eventi Avversi in Chirurgia Urologica: Nostra Esperienza
Authors: Dell'Atti Lucio
Published: February 2013

Introduction

The main purpose of our study was to determine, through the introduction of a checklist in the operating room, the incidence rate of adverse events and their predictability in a representative sample of patients admitted to our Urology unit and undergoing surgery.

Methods

The study includes 324 patients. The checklist includes 3 phases (Sign In, Time Out, Sign Out), 20 items with checks to be performed during surgery and the marking of boxes after a successful check. All the staff in the operating room has been specifically trained with a theoretical and practical 20-hour course.

Results

The overall average incidence of adverse events reported was determined by 4.8%, is consistent with the expectations of the study protocol, and is at a lower level than the average median rate of international studies (8.9%). The overall complication rate fell from 11% to 7.9%, the rate of intrahospital mortality from 1.7% to 0.9%, the rate of surgical site infection decreased from 8.2% to 4.7%.

Conclusions

The results were consistent with the results of other international studies similar in scope in terms of study (definition of the rate of adverse events) and epidemiological study (retrospective study). The variability of the results obtained in our inquiry is likely attributable to varied factors occurred during the study.
Reading Austin Rhetorically
Authors: Munro Andrew
Published: February 2013

This article reads John L. Austin rhetorically and achieves two things thereby. First, it grasps the tensions subtending Austin's speech-act theory. These tensions arguably stem from Austin's distinct engagements with his brief to consider how saying something is to do something. Second, this article assesses the usefulness of Austin's notion of perlocution to the description of discursive events. I take such description to be a concern of the interpretive humanities in general and of rhetoric in particular. To gauge perlocution's utility, I compare its descriptive purchase with that of illocution, signaling some productive affinities between Austin and the purposive, processual conception of semiosis developed by Charles S. Peirce.
Oxygen and Hydrogen Isotopic Preference in Hydration Spheres of Magnesium and Calcium Ions
Authors: Oi Takao , Sato Kunihiko , Umemoto Kazuki
Published: February 2013

Molecular orbital calculations were performed to estimate the 18O/16O and D/H isotopic reduced partition function ratios (rpfrs) of water molecules around magnesium and calcium ions. As model for water molecules in the ith hydration sphere of the cation in aqueous solutions containing that cation, we considered water molecules in the ith hydration sphere that were surrounded by water molecules in the (i+1)th hydration sphere in clusters, M2+(H2O)n (M = Mg or Ca; n up to 100). The calculations indicated that the decreasing order of the 18O preference over 16O in the primary hydration sphere is Mg2+ > Ca2+ > bulk water. That is, water molecules in the primary hydration spheres of the Mg2+ and Ca2+ ions are expected to be enriched in the heavier isotope of oxygen relative to water molecules in bulk, and the degree of the enrichment is larger for the Mg2+ ion than for the Ca2+ ion. No such preference was observed for hydrogen isotopes in any hydration sphere or for oxygen isotopes in the secondary and outer hydration spheres.
Sedation and Analgesia in Mechanically Ventilated Preterm Neonates: Continue Standard of Care or Experiment?
Authors: McPherson Christopher
Published: February 2013

Attention to comfort and pain control are essential components of neonatal intensive care. Preterm neonates are uniquely susceptible to pain and agitation, and these exposures have a negative impact on brain development. In preterm neonates, chronic pain and agitation are common adverse effects of mechanical ventilation, and opiates or benzodiazepines are the pharmacologic agents most often used for treatment. Questions remain regarding the efficacy, safety, and neurodevelopmental impact of these therapies. Both preclinical and clinical data suggest troubling adverse drug reactions and the potential for adverse longterm neurodevelopmental impact. The negative impacts of standard pharmacologic agents suggest that alternative agents should be investigated. Dexmedetomidine is a promising alternative therapy that requires further interprofessional and multidisciplinary research in this population.
Super Tagging in the Development of Sexual Nomenclature and Social Organization Online
Authors: Keilty Patrick
Published: February 2013

In this paper, I describe the ways in which interventionist forms of tagging, such as super tagging, gorilla tagging, and tag bombing within Xtube, a database of sexual representation, reveal complex social and cultural structures among members of sexual subcultures and point to the particularlity of various modes of sexual being and the relationship between those modes and particular configurations of sexual identity. Individuals who participate in super tagging do not necessarily exert significant influence over information retrieval results within a database. Instead, in Xtube, members create alternative, activist, and interventionist forms of tags for personal and social purposes. Particularly for individuals who experience non-normative desire, such tagging practices provide a means for describing and structuring feelings of difference into coherent identities and particular social forms for socio-sexual engagement and self-exploration and understanding.
Fatigue in Multiple Sclerosis
Authors: Herndon Robert M.
Published: February 2013

Fatigue is an important, under-recognized, and complex problem in multiple sclerosis (MS). There are several interacting causes of this fatigue and most will respond to treatment. Factors identified as contributing to the overall problem include disease process related fatigue, fatigue related to intercurrent infection, iatrogenic fatigue (caused by medications), fatigue of handicap, lack of energy related to depression, and fatigue due to disordered or disrupted sleep. Management of fatigue is a multidisciplinary process. Effective treatment requires analysis of the contributing factors in each patient and treatment or management of those factors.
The Management of Spasticity in Multiple Sclerosis
Authors: Gelber David A. , Jozefczyk Patricia B.
Published: February 2013

Spasticity, defined as a velocity-dependent increase in tonic stretch reflexes, is common in patients with multiple sclerosis due to plaque formation in the brain and spinal cord. Treatment of spasticity is generally considered when the increase in tone interferes with functional activities, such as bed or wheelchair positioning, transfers, ambulation, or daily care; when it is painful; or when it leads to complications such as contractures or skin breakdown. This paper reviews the pathophysiology of spasticity and discusses treatment options, including general medical and nursing cares, physical and occupational therapy approaches, use of splints and orthoses, oral and intrathecal medications, nerve blocks, botulinum toxin injections, and orthopedic and neurosurgical procedures.
Results of an Ongoing, Open-Label, Safety-Extension Study of Interferon Beta-1a (Avonex) Treatment in Multiple Sclerosis
Authors: Herndon RM , Jacobs LD , Coats ME , Goodkin DE , Mass MK , Richert JR , Rudick RA , Waubant EL , Weinstock-Guttman B , Scaramucci JO , Burnett BK , Jones WE , Simonian NA
Published: February 2013

In a phase III, double-blind, placebo-controlled, 2-year clinical trial, interferon beta-1a (IFN-β-1a, Avonex) treatment significantly delayed disability progression, decreased exacerbations, and reduced brain lesions on magnetic resonance imaging (MRI) in patients with multiple sclerosis (MS). In this open-label, safety-extension study, we evaluated the longer-term safety and antigenicity of IFN-β-1a. An open-label, safety-extension study of IFN-β-1a, administered at a dose of 30 μg intramuscular (IM) per week in patients with MS, was initiated in May 1995. Subjects enrolled in this study included interferon-naive patients and patients who had prior treatment with either IFN-β-1a in the phase III trial, IFN-β-1b (Betaseron), or both. Safety was evaluated by assessment of adverse events, tolerability by treatment discontinuations, and antigenicity by measurements of neutralizing antibody (NAB) titers. The number of intravenous (IV) steroid courses required per patient per year was determined as a surrogate measure of clinical relapses. There were 382 patients enrolled, with a median duration of treatment, including the phase III trial, of 2.5 years. Twenty-eight percent of participants have been on treatment for at least 3 years. The adverse event profile was similar to that observed in the phase III trial. Injection site reactions were rare and injection site necrosis was not observed. The incidence of NAB to IFN-β over 30 months of treatment was approximately 5%. IFN-β-1a was well tolerated in subjects who had switched from IFN-β-1b. Seventy-seven percent of the patients with NAB to IFN-β-1b at study entry had lost their NAB by month 24 on IFN-β-1a treatment. There was a 47% reduction in IV steroid use in the safety-extension study in those who had previously received placebo in the phase III trial. Long-term treatment of MS patients with IFN-β-1a continues to have a favorable safety profile, with low NAB titers and continuing clinical benefit.
Osteoporosis in Multiple Sclerosis: A Frequent, Serious, and Under-Recognized Problem
Authors: Herndon Robert M. , Mohandas Nirupa
Published: February 2013

Osteoporosis and fractures are extremely common in the multiple sclerosis (MS) population, especially in those women with MS who are postmenopausal and not on hormone replacement therapy (HRT). There is evidence of significantly increased fracture risk in MS patients who have been on steroids, although this appears to be due to increased falls in addition to osteoporosis. Additionally, evidence has indicated that high-dose pulse methylprednisolone has little effect on osteoporosis, but decreased mobility is a very significant factor in decreased bone density. Osteoporosis in MS results in part from causes present in the general population, but is significantly aggravated by immobility and probably by other drugs used to treat MS and its complications, including drugs known to increase bone loss (eg, diphenylhydantoin). Fractures in MS are a particularly serious problem in that the resulting immobility causes deconditioning. A fracture—any fracture—is a much more serious problem in those with MS than in the general population. For example, use of narcotics for pain control in the MS patient with a fracture can convert constipation to obstipation or even bowel obstruction. Deconditioning resulting from injury-related immobility recovers much more slowly than in healthy individuals, and may never return to the preinjury level. Often a fracture converts an individual from being ambulatory to permanent wheelchair status. With preventive measures and moderately effective therapy available, it is important to identify those at risk and initiate appropriate treatment.
Alternative Medicine and Multiple Sclerosis: An Objective Review from an American Perspective
Authors: Bowling Allen C. , Ibrahim Ragaa , Stewart Thomas M.
Published: February 2013

The use of complementary and alternative medicine (CAM), or unconventional medicine, may be challenging for health care providers in the United States. There are several definitions of CAM, and therapies that are considered alternative in one country may be conventional in other countries. Unconventional medical practices may be used instead of, or in addition to, conventional medical therapy. It may be difficult for people with multiple sclerosis (MS) to obtain reliable MS-relevant CAM information, and there may be conflicts between the values of patients and those of health care providers. These issues may create problems in the clinical decision-making process. The relevance to MS of some commonly used CAM therapies is discussed: herbal medicine, vitamins and minerals, marijuana, and a histamine and caffeine transdermal gel patch. Current information about the efficacy and safety of CAM therapies is extremely variable. Some therapies appear promising, others are unsafe or ineffective, and nearly all need to be studied further.
School Outcomes of Aggressive‐Disruptive Children: Prediction From Kindergarten Risk Factors and Impact of the Fast Track Prevention Program
Authors: Bierman Karen L. , Coie John , Dodge Kenneth , Greenberg Mark , Lochman John , McMohan Robert , Pinderhughes Ellen ,   Conduct Problems Prevention Research Group
Published: February 2013

A multi‐gate screening process identified 891 children with aggressive‐disruptive behavior problems at school entry. Fast Track provided a multi‐component preventive intervention in the context of a randomized‐controlled design. In addition to psychosocial support and skill training for parents and children, the intervention included intensive reading tutoring in first grade, behavioral management consultation with teachers, and the provision of homework support (as needed) through tenth grade. This study examined the impact of the intervention, as well as the impact of the child's initial aggressive‐disruptive behaviors and associated school readiness skills (cognitive ability, reading readiness, attention problems) on academic progress and educational placements during elementary school (Grades 1–4) and during the secondary school years (Grades 7–10), as well as high school graduation. Child behavior problems and skills at school entry predicted school difficulties (low grades, grade retention, placement in a self‐contained classroom, behavior disorder classification, and failure to graduate). Disappointingly, intervention did not significantly improve these long‐term school outcomes. Aggr. Behav. 39:114–130, 2013. © 2013 Wiley Periodicals, Inc.
A Large Magnetoresistance Effect in p–n Junction Devices by the Space‐Charge Effect
Authors: Yang Dezheng , Wang Fangcong , Ren Yang , Zuo Yalu , Peng Yong , Zhou Shiming , Xue Desheng
Published: February 2013

The finding of an extremely large magnetoresistance effect on silicon based p–n junction with vertical geometry over a wide range of temperatures and magnetic fields is reported. A 2500% magnetoresistance ratio of the Si p–n junction is observed at room temperature with a magnetic field of 5 T and the applied bias voltage of only 6 V, while a magnetoresistance ratio of 25 000% is achieved at 100 K. The current‐voltage (I–V) behaviors under various external magnetic fields obey an exponential relationship, and the magnetoresistance effect is significantly enhanced by both contributions of the electric field inhomogeneity and carrier concentrations variation. Theoretical analysis using classical p–n junction transport equation is adapted to describe the I–V curves of the p–n junction at different magnetic fields and reveals that the large magnetoresistance effect origins from a change of space‐charge region in the p–n junction induced by external magnetic field. The results indicate that the conventional p–n junction is proposed to be used as a multifunctional material based on the interplay between electronic and magnetic response, which is significant for future magneto‐electronics in the semiconductor industry.
Tacrolimus‐associated posterior reversible encephalopathy syndrome in hematopoietic allogeneic stem cell transplantation
Authors: Hammerstrom Aimee E. , Howell Joshua , Gulbis Alison , Rondon Gabriela , Champlin Richard E. , Popat Uday
Published: February 2013

Tacrolimus‐associated posterior reversible encephalopathy syndrome (PRES) is a potential complication of allogeneic stem cell transplant (SCT). Due to the paucity of information on the management of PRES in SCT patients receiving tacrolimus, more information is needed on trends associated with the incidence of PRES and to characterize its management. A retrospective review was conducted of patients receiving tacrolimus for prevention of graft versus host disease (GVHD) after allogeneic SCT who developed PRES from September 2008 to July 2011. Nineteen patients were identified. Altered mental status, seizures, and visual abnormalities were experienced by 78.9%, 52.6%, and 31.5% of the patients, respectively, at time of PRES onset. Compared with baseline, patients with PRES were likely to have an increase in mean arterial pressure (P  <  0.0001) and serum creatinine. Elevated tacrolimus levels and hypomagnesemia were not observed with PRES onset. Tacrolimus was managed in three general strategy groups: not held, held then continued, and switched to another agent. Survival was defined as survival to discharge from PRES hospitalization. When tacrolimus was not held, held then continued, or switched to another agent, 40% (2 of 5), 40% (4/10), and 50% (2/4) survived to discharge, respectively. PRES was associated with high blood pressure and adequate blood pressure control should be part of its management. No management strategy pertaining to tacrolimus usage appeared more beneficial over another. Am. J. Hematol. 88:301–305, 2013. © 2013 Wiley Periodicals, Inc.
Learning social studies via objects in museums: investigation into Turkish elementary school students' lived experiences
Authors: Yilmaz Kaya , Filiz Nilufer , Yilmaz Ali
Published: February 2013

Based on a descriptive phenomenological research design, this study investigated Turkish elementary school students' experiences in learning social studies via objects in museums. After students visited four different museums during the teaching of three thematic units at sixth grade level, their lived experiences were elicited. Purposeful sampling was used to select the research participants and interviews were employed to gather data. The research data were analyzed by means of Giorgi's descriptive phenomenological framework, which helped reveal the structure of the phenomenon of learning social studies in museums. It was found that the essence of learning social studies via objects in museums consisted of five components. These were (1) excitement and motivation to learn about the past, (2) active participation in the learning process, (3) reconstruction of historical knowledge with the development of historical thinking skills, (4) enjoying social studies learning, and (5) heightened interest in social studies and seeing it as a valuable school subject. It was also found that some students had difficulties or negative learning experiences in their museum visits, such as difficulty in asking object‐based questions or making comments on objects and relating them to the lessons being studied in the class. Because only a few students mentioned these difficulties, they were not included in the essence of the lived experience of learning social studies via objects in museums.
Respiratory and behavioral dysfunction following loss of the GABAA receptor α4 subunit
Authors: Loria C. Jean , Stevens Ashley M. , Crummy Ellen , Casadesus Gemma , Jacono Frank J. , Dick Thomas E. , Siegel Ruth E.
Published: February 2013

γ‐Aminobutyric acid type A (GABAA) receptor plasticity participates in mediating adaptation to environmental change. Previous studies in rats demonstrated that extrasynaptic GABAA receptor subunits and receptors in the pons, a brainstem region involved in respiratory control, are upregulated by exposure to sustained hypobaric hypoxia. In these animals, expression of the mRNA encoding the extrasynaptic α4 subunit rose after 3 days in sustained hypoxia, while those encoding the α6 and δ subunits increased dramatically by 2 weeks. However, the participation of extrasynaptic subunits in maintaining respiration in normoxic conditions remains unknown. To examine the importance of α4 in a normal environment, respiratory function, motor and anxiety‐like behaviors, and expression of other GABAA receptor subunit mRNAs were compared in wild‐type (WT) and α4 subunit‐deficient mice. Loss of the α4 subunit did not impact frequency, but did lead to reduced ventilatory pattern variability. In addition, mice lacking the subunit exhibited increased anxiety‐like behavior. Finally, α4 subunit loss resulted in reduced expression of other extrasynaptic (α6 and δ) subunit mRNAs in the pons without altering those encoding the most prominent synaptic subunits. These findings on subunit‐deficient mice maintained in normoxia, in conjunction with earlier findings on animals maintained in chronic hypoxia, suggest that the expression and regulation of extrasynaptic GABAA receptor subunits in the pons is interdependent and that their levels influence respiratory control as well as adaptation to stress.
Numerical Study on the Effect of Cavitation on Flow and Diesel Fuel Atomization Characteristics
Authors: Sadegharani H. , Haghshenasfard M. , Salimi J.
Published: February 2013

Computational fluid dynamics (CFD) models based on the turbulent mixture multiphase model were applied to consider the effect of cavitation on the spray of diesel fuel. The effects of injection pressure and length‐to‐width (L/W) ratio on the velocity distribution, cavitation number, discharged coefficient, and nozzle exit velocity were investigated and the performance of the model was compared with the experimental data. The results indicate that the cavitation generated in the nozzle has a strong impact on the fuel injection and spray quality, whereas the L/W ratio is a highly effective parameter for cavitation behavior. In addition, by increasing the L/W ratio, the range of cavitation number, wall friction, and flow resistance increase but in the cavitation region the velocity profile in radial and axial directions, spray cone angle, nozzle exit velocity, and the discharged coefficient decrease.
Hydrogenation of Vegetable Oil – Mechanism and Kinetics
Authors: Kuchling Thomas , Wollmerstädt Hendrik , Endisch Matthias
Published: February 2013

Experimentelle Untersuchungen zur Hydrierung von Pflanzenölen für die Herstellung hochwertiger Dieselkraftstoffkomponenten in einem kontinuierlich arbeitenden Rieselbettreaktor werden vorgestellt. Anhand der experimentellen Ergebnisse wird der Reaktionsablauf diskutiert und ein globaler, strukturgruppenbasierter Reaktionsmechanismus postuliert. Darauf aufbauend wird ein formalkinetisches Modell vorgestellt, das auch die Bildung von Zwischenprodukten erfasst und als Grundlage für die Auslegung technischer Reaktoren verwendet werden kann.
Developments in near‐infrared‐guided hepatobiliary, pancreatic and other upper gastrointestinal surgery
Authors: Murawa Dawid , Polom Karol , Rho Young Soo , Murawa Pawel
Published: February 2013

With the development of near‐infrared (NIR) technology, real‐time utility of NIR and its fluorophores has gained vast interest among surgeons of various sub‐disciplines. The purpose of this review is to assess and explore the most recent developments in NIR‐guided surgery in an upper gastrointestinal (UGI) surgical setting. Queries of PubMed and Medline literature databases was performed for experimental and clinical studies relevant to NIR use in the context of UGI surgery. NIR‐guided UGI surgeries have been reported to be valuable in: (1) esophageal anastomosis; (2) sentinel lymph node biopsy in gastric cancer; (3) detection of liver and pancreatic tumors; and (4) detection of extra bile duct and bile duct injuries. Although NIR technology has shown tremendous promise in UGI surgery, its full clinical translation and wider adaptation remains to be seen. Copyright © 2013 John Wiley & Sons, Ltd.
Synthesis and evaluation of a polydisulfide with Gd–DOTA monoamide side chains as a biodegradable macromolecular contrast agent for MR blood pool imaging
Authors: Ye Zhen , Wu Xueming , Tan Mingqian , Jesberger Jack , Grisworld Mark , Lu Zheng‐Rong
Published: February 2013

Macromolecular Gd(III)‐based contrast agents are effective for contrast‐enhanced blood pool and cancer MRI in preclinical studies. However, their clinical applications are impeded by potential safety concerns associated with slow excretion and prolonged retention of these agents in the body. To minimize the safety concerns of macromolecular Gd contrast agents, we have developed biodegradable macromolecular Gd contrast agents based on polydisulfide Gd(III) complexes. In this study, we designed and synthesized a new generation of the polydisulfide Gd(III) complexes containing a macrocyclic Gd(III) chelate, Gd–DOTA monoamide, to improve the in vivo kinetic inertness of the Gd(III) chelates. (N6‐Lysyl)lysine‐(Gd–DOTA) monoamide and 3‐(2‐carboxyethyldisulfanyl)propanoic acid copolymers (GODC) were synthesized by copolymerization of (N6‐lysyl)lysine DOTA monoamide and dithiobis(succinimidylpropionate), followed by complexation with Gd(OAc)3. The GODC had an apparent molecular weight of 26.4 kDa and T1 relaxivity of 8.25 m m−1 s−1 per Gd at 1.5 T. The polymer chains of GODC were readily cleaved by l‐cysteine and the chelates had high kinetic stability against transmetallation in the presence of an endogenous metal ion Zn2+. In vivo MRI study showed that GODC produced strong and prolonged contrast enhancement in the vasculature and tumor periphery of mice with breast tumor xenografts. GODC is a promising biodegradable macromolecular MRI contrast agent with high kinetic stability for MR blood pool imaging. Copyright © 2013 John Wiley & Sons, Ltd.
Interstate Crossing‐Induced Chemiexcitation as the Reason for the Chemiluminescence of Dioxetanones
Authors: Pinto da Silva Luís , Esteves da Silva Joaquim C. G.
Published: February 2013

The decomposition reaction of dimethyl‐1,2‐dioxetanone in dichloromethane was studied by using a DFT approach. The low efficiency of triplet and singlet excited‐state formation was rationalised. A charge‐transfer process was demonstrated to be involved in the chemiluminescence process. Present and previous results allow us to define an interstate crossing‐induced chemiexcitation (ICIC) mechanism for the chemiluminescence of dioxetanones. Charge transfer is needed to reach a transition state, in the vicinity of which direct population of excited states is possible. The chemiexcitation process is then governed by singlet/triplet intersystem crossings. Structural modifications then modify the rate of these crossings and the singlet ground and excited‐state interaction, thereby modulating the efficiency of this process and the spin of the resulting products.
Optimization and validation of CEDIA drugs of abuse immunoassay tests in serum and urine on an Olympus AU 400
Authors: Musshoff F. , Wolters T. , Lott S. , Ippisch J. , Gradl S. , Madea B.
Published: February 2013

A preliminary initial cloned enzyme donor immunoassay (CEDIA) was optimized for serum and urine drug testing with respect to the German per se limits for driving under the influence of drugs (serum) and lowered cut‐offs in cases of driving licence re‐granting (urine). The tests were performed on an Olympus AU 400 auto analyzer. Validation revealed sensitivities between 93% and 100% based on comparison with data from gas or liquid chromatography coupled with mass spectrometry. Even if specificity ranged between 83% and 98 %, the tests can be considered useful for forensic purposes. Receiver operating characteristic (ROC) curves, Youden indices, as well as positive and negative predictive values are presented. Copyright © 2013 John Wiley & Sons, Ltd.
What constitutes clinically significant binge eating? Association between binge features and clinical validators in college‐age women
Authors: Vannucci Anna , Theim Kelly R. , Kass Andrea E. , Trockel Mickey , Genkin Brooke , Rizk Marianne , Weisman Hannah , Bailey Jakki O. , Sinton Meghan M. , Aspen Vandana , Wilfley Denise E. , Taylor C. Barr
Published: February 2013

Objective:

To investigate the association between binge features and clinical validators.

Method:

The Eating Disorder Examination assessed binge features in a sample of 549 college‐age women: loss of control (LOC) presence, binge frequency, binge size, indicators of impaired control, and LOC severity. Clinical validators were self‐reported clinical impairment and current psychiatric comorbidity, as determined via a semistructured interview.

Results:

Compared with women without LOC, those with LOC had significantly greater odds of reporting clinical impairment and comorbidity (ps < 0.001). Among women with LOC (n = 252), the indicators of impaired control and LOC severity, but not binge size or frequency, were associated with greater odds of reporting clinical impairment and/or comorbidity (ps < 0.05).

Dicussion:

Findings confirm that the presence of LOC may be the hallmark feature of binge eating. Further, dimensional ratings about the LOC experience—and possibly the indicators of impaired control—may improve reliable identification of clinically significant binge eating. © 2013 by Wiley Periodicals, Inc. (Int J Eat Disord 2013)
Dipotassium Diaquadiphosphatooctaperoxotetramolybdate, [K2(P2O7){MoO(O2)2}2{MoO(O2)2(OH2)}2]2– – a One‐Dimensional Double Chain Array of Polyanions Linked by Potassium Cations
Authors: Aoki Koji , Iwata Keisuke , Iwata Takahiro , Hashimoto Masato
Published: February 2013

A dipotassium diaquadiphosphatooctaperoxotetramolybdate, [K2(P2O7){MoO(O2)2}2{MoO(O2)2(OH2)}2]2–, was crystallised as a tetramethylammonium salt and its structure was determined by single‐crystal X‐ray diffraction. The diaquadiphosphatooctaperoxotetramolybdate moiety (POPMo4) consists of four molybdenum decahedra and one μ4‐diphosphate group. All Mo atoms bear two peroxo groups at their equatorial positions. Two of the four Mo atoms are also coordinated by a water molecule. The four molybdenum decahedra are separated and linked by the diphosphate group. The POPMo4 moieties are linked by potassium atoms to form an infinite anionic 1D double chain. The chains are connected by hydrogen bonds to water of crystallisation molecules to form a 2D network. POPMo4 or its precursor gives a 31P NMR signal at δ = –7.3 ppm in the reaction solution and is stable at low pH and a high Mo/diphosphate molar ratio.
General Approach to Prostanes B1 by Intermolecular Pauson–Khand Reaction: Syntheses of Methyl Esters of Prostaglandin B1 and Phytoprostanes 16‐B1‐PhytoP and 9‐L1‐PhytoP
Authors: Vázquez‐Romero Ana , Verdaguer Xavier , Riera Antoni
Published: February 2013

A synthetic approach to the methyl esters of Prostaglandin B1 and Phytoprostanes 16‐B1‐PhytoP (PPB1‐I) and 9‐L1‐PhytoP (PPB1‐II) based on the modified Julia olefination of a formylcyclopentenone and an appropriately protected hydroxy sulfone has been developed. The cyclopentenones were efficiently prepared by intermolecular Pauson–Khand reaction of a (silyloxymethyl)alkyne. The sulfone counterpart was prepared by regioselective ring‐opening of the appropriate chiral epoxides by 2‐mercaptobenzothiazole. The protecting group for the alcohol functionality on the sulfone proved to be crucial. Protection as a tert‐butyl ether was the best solution, giving better results than a tert‐butyldimethylsilyl ether.
Tropanes as Scaffolds for Phosphorus–Olefin Ligands and Their Application in Asymmetric Catalysis
Authors: Vlahovic Sandra , Schädel Nicole , Tussetschläger Stefan , Laschat Sabine
Published: February 2013

Tropane‐derived phosphorus–olefin hybrid ligands bearing various combinations of P‐units (chiral BINOL‐derived units/achiral PPh2‐units) with a tropene skeleton (chiral/achiral) have been synthesized and used in Cu‐catalysed conjugate 1,4‐additions of diethylzinc to cyclic enones and in Rh‐catalysed 1,4‐additions of phenylboronic acid (Hayashi–Miyaura reaction) with cyclic and acyclic enones. Whereas in Cu‐catalysed reactions only moderate yields and ee values (up to 49 % ee) were obtained, up to 97 % ee was observed in the Hayashi–Miyaura reaction with various substrates. The most promising results in both reactions were achieved with ligands 11 and 15, which contain a chiral alkene/achiral P‐unit or an achiral alkene/chiral P moiety, respectively, and where the metal is complexed on the exo side of the tropene skeleton. In contrast, ligands with an endo coordination mode showed only low (13) or no activity (12) in all of the 1,4‐additions. NMR and ESI‐MS experiments revealed the presence of two cationic [RhI(15)2]+ species in solution.
Prins‐Type Cyclization Reactions in Natural Product Synthesis
Authors: Han Xun , Peh GuangRong , Floreancig Paul E.
Published: February 2013

Prins‐type cyclization reactions proceed through the intramolecular addition of a π‐nucleophile to an oxocarbenium ion or related species to generate a ring through carbon–carbon bond formation, often with excellent and predictable stereocontrol. The widespread presence of naturally occurring oxygen‐containing heterocycles has made these reactions exceedingly valuable for total synthesis efforts. This microreview covers several common variations of Prins‐type cyclizations and highlights their applicability to the total synthesis of natural products and analogs.
Ectoine production by Alkalibacillus haloalkaliphilus—Bioprocess development using response surface methodology and model‐driven strategies
Authors: Bergmann Sven , David Florian , Franco‐Lara Ezequiel , Wittmann Christoph , Krull Rainer
Published: February 2013

Halophile microorganisms are important ectoine producers and are applied in industrial applications. The growth and osmoregulation are distinguished based on the diversity of environmental distribution and require holistic investigations of cultivation condition and osmotic response. The barely investigated halophilic bacterium Alkalibacillus haloalkaliphilus is able to accumulate the compatible solute ectoine, while growing under environmental stress conditions. Since microbial growth and ectoine production are functions of the process key parameters such as salinity, pH value, and temperature, the optimization resulted in three significant process strategies that were estimated by response surface methodology. For each strategy, single‐cell analysis was performed using a newly developed staining method for monitoring the membrane potential of halophilic microorganisms directly in the cultivation medium. The flow cytometric method was shown to reveal the physiological state during ectoine production and has a great potential to be applied for basic research, process optimization, and quality control.
Day‐to‐day ionospheric variability due to lower atmosphere perturbations
Authors: Liu H.‐L. , Yudin V. A. , Roble R. G.
Published: February 2013

Ionospheric day‐to‐day variability is a ubiquitous feature, even in the absence of appreciable geomagnetic activities. Although meteorological perturbations have been recognized as an important source of the variability, it is not well represented in previous modeling studies and the mechanism is not well understood. This study demonstrates that the thermosphere‐ionosphere‐mesosphere‐electrodynamics general circulation model (TIME‐GCM) constrained in the stratosphere and mesosphere by the hourly whole atmosphere community climate model (WACCM) simulations is capable of reproducing observed features of day‐to‐day variability in the thermosphere‐ionosphere. Realistic weather patterns in the lower atmosphere in WACCM were specified by Modern Era Retrospective Reanalysis for Research and Application (MERRA). The day‐to‐day variations in mean zonal wind, migrating and nonmigrating tides in the thermosphere, vertical and zonal E × B drifts, and ionosphere F2 layer peak electron density (NmF2) are examined. The standard deviations of the drifts and NmF2 show local time and longitudinal dependence that compare favorably with observations. Their magnitudes are 50% or more of those from observations. The day‐to‐day thermosphere and ionosphere variability in the model is primarily caused by the perturbations originated in lower atmosphere, since the model simulation is under constant solar minimum and low geomagnetic conditions.
Insignificant solar‐terrestrial triggering of earthquakes
Authors: Love Jeffrey J. , Thomas Jeremy N.
Published: February 2013

We examine the claim that solar‐terrestrial interaction, as measured by sunspots, solar wind velocity, and geomagnetic activity, might play a role in triggering earthquakes. We count the number of earthquakes having magnitudes that exceed chosen thresholds in calendar years, months, and days, and we order these counts by the corresponding rank of annual, monthly, and daily averages of the solar‐terrestrial variables. We measure the statistical significance of the difference between the earthquake‐number distributions below and above the median of the solar‐terrestrial averages by χ2 and Student's t tests. Across a range of earthquake magnitude thresholds, we find no consistent and statistically significant distributional differences. We also introduce time lags between the solar‐terrestrial variables and the number of earthquakes, but again no statistically significant distributional difference is found. We cannot reject the null hypothesis of no solar‐terrestrial triggering of earthquakes.
The conjunctive trace
Authors: Richards Blake A. , Frankland Paul W.
Published: February 2013

Memories serve to establish some permanence to our inner lives despite the fleeting nature of subjective experience. Most neurobiological theories of memory assume that this mental permanence reflects an underlying cellular permanence. Namely, it is assumed that the cellular changes which first occur to store a memory are perpetuated for as long as the memory is stored. But is that really the case? In an opinion piece in this issue of Hippocampus, Aryeh Routtenberg raises the provocative idea that the subjective sense of memory persistence is not in fact a result of persistence at the cellular level, rather, that “supple synapses” and multiple “evanescent networks” that are forever changing are responsible for our memories. On one level, his proposal could be construed as a radical challenge to some of our most fundamental theories of the neurobiology of memory, including Donald Hebb's proposal that memories are stored by networks that strengthen their connections to increase the likelihood of the same activity patterns being recreated at a later date. However, it could also be seen as a moderating call, a call for a greater acknowledgement of the dynamic, stochastic, and distributed nature of neural networks. In this response to Routtenberg's article, we attempt to provide a clarification of the dividing line between these two interpretations of his argument, and in doing so, we provide some overview of the empirical evidence that bears on this subject. We argue that the data that exists to date favors the more moderate interpretation: that memory storage involves a process in which activity patterns are made more likely to reoccur, but that an under‐appreciated reality is that mnemonic traces may continue to change and evolve over time. © 2013 Wiley Periodicals, Inc.