bluuebunny/crossref_metadata_2025 huggingface dataset:
Molybdate Corrosion Inhibition in Deaerated and Low-Oxygen Waters
Authors: Weber T. R. , Stranick M. A. , Vukasovich M. S.
Published: June 2011

The inhibiting effect of sodium molybdate on mild steel corrosion in deaerated and low-oxygen concentration waters at pH 9.0 and 60 C was investigated using weight loss and electrochemical test methods. Molybdate was inhibitive at a water oxygen concentration between 1 and 2.5 mg/L. In combinations with sodium nitrite, molybdate exhibited synergistic inhibition at 1 mg/L oxygen. An explanation of the observed synergism is discussed based on the electrochemical study.
A New Electrochemical Potentiokinetic Reactivation Test for Determining Degree of Sensitization in Ferritic Stainless Steels
Authors: Lee J. B.
Published: June 2011

An electrochemical potentiokinetic reactivation (EPR) test has been developed for quantifying the degree of sensitization of ferritic stainless steels (SSs). This test is applicable to AISI 430, 430 Ti, 430 Nb, 434, 444, and 446. The test is conducted at 30 C in a deaerated 3 to 5 N H2SO4 solution. A test specimen is first passivated at + 400 mVSCE for 2 to 10 min, depending on the grade of SS, and then subjected to a reactivation step where the potential is decreased at a rate of 100 to 250 mV/min toward the open circuit potential (OCP) to determine whether a reactivation peak occurs. Results of the EPR test agree well with those of the Cu-CuSO4-50% H2SO4 immersion test.
Environmental Cracking of High Strength Maraging Steels: Part 2—Gaseous Fluoride Atmospheres
Authors: Bradhurst D. H. , Heuer P. M.
Published: June 2011

An investigation was made of the susceptibility to cracking of two commercial 350 grades of maraging steel. Tensile tests were carried out on samples of the steels at very slow strain rates, and the load at failure was used to assess the susceptibility of the steels to cracking in an environment of gaseous uranium hexafluoride and hydrogen fluoride at 70 C. Good resistance to cracking was observed in dry uranium hexafluoride gas but cracking occurred when hydrogen fluoride was present at partial pressures above about 1 kPa. The failure stress decreased with increasing pressure of hydrogen fluoride. Scanning electron microscopy revealed brittle fracture surfaces in all cases where failure occurred at low stress, while failures at high stress were usually ductile in appearance. In view of the susceptibility of these steels to hydrogen embrittlement, it is suggested that the mechanism of failure in the presence of HF was associated with reaction-produced hydrogen. Oxide coated samples prepared by air aging, did not have significantly better resistance to cracking than vacuum aged Samples in the UF6/HF environment.
An Initial Investigation of Calcareous Deposits upon Cathodic Steel Surfaces in Sea Water
Authors: Wolfson S. L. , Hartt W. H.
Published: June 2011

The influence of potential and nominal sea water velocity upon the nature of calcareous deposits formed upon a cathodic steel surface has been investigated. Specific attention was focused upon change with exposure time of the current density to maintain a prescribed cathodic potential and upon thickness of the calcareous film. Equations have been developed whereby pH of the electrolyte adjacent to both a filmed and film-free surface can be rationalized in terms of cathodic current density and character of the electrolyte flow. Structure of calcareous deposits was investigated by scanning electron microscopy. Results are discussed within the frame of current understanding of marine cathodic protection and cathodic protection practices.
Corrosion Inhibition of a Carbon Steel in 3% NaCl Solutions by Aliphatic Amino-Alcohol and Diamine Type Compounds
Authors: Duprat Michel , Dabosi Francis
Published: June 2011

Following the results previously obtained on the inhibiting effect of 2-ethylamino-ethanol, electrochemical corrosion rate measurement techniques (plotting of steady state polarization curves and polarization resistance measurements) were carried out in aerated and stirred 3% NaCl solutions containing various similar organic molecules (amino-alcohols and diamines). A comparative study of their efficiency was undertaken. Because most of these coumpounds exert a strong alkalizing effect on the saline solutions, they are characterized by means of the differential inhibitive efficiency concept which gives an account of the intrinsic inhibiting action of the compound and from which the influence of the pH rising is eliminated. The results of this comparative study corroborate the surface chelate formation as previously assumed to account for the intrinsic inhibiting action of 2-ethylamino-ethanol.
Determination of Stress Corrosion Cracking Resistance of Al-Cu-Mg Alloys by Slow Strain Rate and Alternate Immersion Testing
Authors: Maitra Shantanu
Published: June 2011

Increased artificial aging from the T351 temper to T851 temper is known to increase resistance to stress corrosion cracking (SCO for Al-Cu-Mg alloy 2124. A series of incrementally aged 2124 alloy plate was tested for resistance to SCC by the slow strain rate technique and by the conventional alternate immersion test method. It is shown that slow strain rate test results are in agreement with the conventional test results. Using fracture energy and other loss in ductility parameters to denote resistance to SCC, it has been shown that this technique can be used as a more accurate SCC test. SEM examinations of fracture surfaces confirm the SCC indices obtained by the slow strain rate test.
Formation of Spherical Colloidal Nickel Ferrite Particles as Model Corrosion Products
Authors: Regazzoni Alberto E. , Matijević Egon
Published: June 2011

Ni-ferrite particles of various sizes and chemical compositions were prepared by aging at 90 C for different periods of time coprecipitated ferrous and nickel hydroxide gels in the presence of nitrate ion. The size and the stoichiometry of the final solids were found to be strongly dependent on the initial composition of the systems. Under certain conditions, the so prepared particles are spherical and of narrow size distribution. The formation of Ni-ferrite by incorporation of Ni2+ ions into magnetite, crystallizing from a ferrous hydroxide gel at 90 C in a mild oxidative medium, was also studied. The developed procedures suggest possible pathways by which the corrosion crud is formed in nuclear power plants.
An Electrochemical Method for Hydrogen Determination in Steel
Authors: Zakroczymski Tadeusz
Published: June 2011

A sensitive method for determination of the amount of absorbed hydrogen and its forms in metal (steel) is described. The method is based on the electrochemical measurement of hydrogen desorption rate. An analysis of the pertinent equations for the diffusion controlled desorption process is given and suggestions are made regarding uses of the method.
Pit Formation in the Cathodic Polarization of Passive Iron IV. Repair Mechanism by Molybdate, Chromate and Tungstate
Authors: Ogura Kotaro , Ohama Takahiko
Published: June 2011

The effect of molybdate, chromate and tungstate on the pitting resistance of iron has been investigated, and the repair mechanism is considered. Molybdate enhanced the pitting resistance with increasing the concentration, which was attributed to the polymolybdate's ability to adsorb or precipitate as a salt. Chromate inhibited the pitting formation effectively at higher concentration, but pitting was expedited at lower concentration. The inhibition of pitting by chromate was related to the deposition of a protective layer involving chromium hydroxide or oxide at a lower concentration; however, chromate stimulated the anodic reaction, which created a situation in favor of pitting formation. Tungstate had no positive effect on the pitting resistance; pitting was accelerated at a higher concentration (≥0.2 M), which was rationalized by assuming that the polytungstate neither adsorbed on passive iron nor precipitated as a salt with iron ion.
The Influence of Applied Stress and Surface Finish on the Pitting Susceptibility of Low Alloy Turbine Disk Steels in Wet Steam
Authors: Lennon S. J. , Robinson F. P. A. , Garrett G. G.
Published: June 2011

The effects of applied tensile and compressive stresses and surface finish on the pitting susceptibility, and hence stress corrosion crack initiation, of 34CrNiMo6 and 26NiCrMoV145 steam turbine disk steels were studied. In an attempt to simulate actual conditions, all tests were conducted in an aerated wet steam environment. Four-point bend specimens were used in the study, and scanning electron microscopy (SEM) was used to examine any pits and cracks found in the specimens. It was found that 34CrNiMo6 is more susceptible to pitting than 26NiCrMoV145, that testing time influences the degree of pitting on differently machined surfaces, and that pitting susceptibility increases with increasing applied tensile stress.
Facial resemblance and attractiveness: an experimental study in rural Indonesia
Authors: Nojo Saori , Ihara Yasuo , Furusawa Hana , Akamatsu Shigeru , Ishida Takafumi
Published: June 2011

Previous studies suggest that humans use facial characteristics as a cue of kinship in a context-dependent manner: a self-resembling face is preferred as a target of cooperation because cooperating with kin enhances inclusive fitness, but avoided as a mating partner because mating with kin increases the risk of inbreeding. Another line of evidence indicates that children internalize faces of their family members and later use them as a referent with which faces of others are compared. Using digital morphing techniques, we conduct an experiment in a village in Sumba, Indonesia, to investigate effects of facial self- or parent-resemblance on perceived attractiveness of opposite-sex faces in the context of a long-term or short-term relationship. Our results show that females prefer a male face not resembling themselves and males prefer a female face not resembling their mothers, both in the long-term context.
Results following Repair of Gluteus Medius Defects following Total Hip Arthroplasty
Authors: Rajkumar Shanmugasundaram , Singer Gian C. , Jones Jonathan R.
Published: June 2011

13 patients with tears in the gluteus medius tendon following total hip arthroplasty were studied. The diagnosis of a gluteal tear was made on the basis of clinical signs and a positive arthrogram of the hip in all cases. 11 patients underwent gluteus medius repair and two patients declined surgery. 10 patients attended a review clinic (eight gluteal repair patients and two conservatively managed patients) and three were reviewed by telephone and medical notes. The mean follow up was 61 months (range 12–116 months). The mean age at follow up was 71.42 years (69–79 years) and the male to female ratio was 5:8. The mean duration of symptoms prior to repair was 16 months. An anterolateral transgluteal approach had been used for primary surgery in nine cases and in four cases the original surgical approach was unknown.

The mean Harris Hip score prior to repair was 77.4 (range 55–87), which improved to a mean post operative Harris hip score of 86.97 (range 79–96) following repair. The Oxford hip score prior to repair was 20 (range 16–25) which improved to a mean of 14.2 after repair (range 4–29). 9 out of 11 patients who had the repair were satisfied and would recommend the procedure. We believe an accurate and timely diagnosis together with repair can reduce the morbidity associated with this post-operative complication following THA.
Total Hip Arthroplasty for Acute Displaced Femoral Neck Fractures via the Posterior Approach: A Protocol to Minimise Hip Dislocation Risk
Authors: Ricci William M. , Langer Jakub S. , Leduc Stéphane , Streubel Philipp N. , Borrelli Joseph
Published: June 2011

Total hip arthroplasty (THA) is considered superior to hip hemiarthroplasty (HHA) in long term pain relief and functional outcome after femoral neck fracture; high early dislocation rates may however negate these advantages. This study elucidates whether a protocol of careful patient selection, surgical technique algorithm and use of modern implants could yield low dislocation rates in hip fracture patients treated with THA via the posterior approach. Over a seven year period all patients admitted to our institution that were cognitively lucid, independent ambulators and without Parkinson's disease underwent THA for acute displaced femoral neck fractures using a posterior approach, large femoral heads, elevated acetabular liners and a surgical technique algorithm. Twenty-nine THAs were performed in 26 patients (mean age of 71 years, range 50–87 years) and were followed for a mean of 32 months (range 13–48 months). There was one dislocation 7 weeks postoperatively in a non-compliant patient resulting in reoperation. There were no other reoperations or major complications. Our results indicate that low dislocation rates can be accomplished for displaced femoral neck fractures treated with THA via the posterior approach using a protocol that includes careful patient selection, surgical technique focused on intraoperative stability, and the use of modern implants.
Prevalence of Parkinsonism in Older Patients with Hip Fracture
Authors: Yiannopoulou Konstantina G. , Papageorgiou Sokratis G. , Anastasiou Ioannis P. , Ganetsos Theodore K. , Karydakis Kleanthis D.
Published: June 2011

Parkinsonism in hip fracture (HF) patients is a potential source for complications during surgery, postoperative period and rehabilitation and a risk factor of second HF. We investigated whether parkinsonism was more prevalent in older subjects with HF than in other older patient groups undergoing surgery.

We prospectively assessed patients who had suffered HF and controls. We assigned all patients aged 68 and older admitted in our hospital for HF surgery during last year and compared them with age-and gender matched patients attending other surgical departments. 80 HF patients and 80 controls were assessed for parkinsonism.

Parkinsonism was common in both groups, presumably reflecting the mean ages of approximately 80 years, plus hospitalization-status. However, parkinsonism was much higher in the hip fracture group (76.25%) compared to the control hospitalised subjects (37.5%; p<0.001). The majority of HF patients with parkinsonism were undiagnosed for their parkinsonism symptoms prior to HF and the same was observed in the control group (91.8% and 86.7% respectively, p= 0.471). Among those with parkinsonism, pre-hospitalization drug therapy may have been contributory in 24.5% of HF patients and 30% of controls (p=0.589).

Parkinsonism is very common in older patients admitted for surgery to a general hospital and extremely common in those with HF. It seems that parkinsonism, is heavily under recognised in the elderly. Our data seem to confirm that Parkinsonism is a major risk factor of HF in the elderly.
Quantum Mechanical Investigation of the Electric and Thermal Characteristics of Magnetic Compound Fluid as a Semiconductor on Metal Combined with Rubber
Authors: Shimada Kunio
Published: June 2011

By applying our developed intelligent fluid, magnetic compound fluid (MCF), to silicon oil rubber, we have made the MCF rubber highly sensitive to temperature and electric conduction. MCF is useful as an element material in haptic robot sensors and other related devices. By mixing metal particles in the silicon oil rubber and by applying a strong magnetic field to the rubber, high-density clusters of these particles can be formed. In a previous study, we investigated the electric current resulting from the applied voltage. In the present paper, we discuss the capacitance of the MCF rubber. The capacitance as well as the electric current can be explained by quantum theory and behaves as a semiconductor. Regarding the thermal characteristics, in the present paper, the thermal effect on the electric current and the temporary thermal conductivity differ depending on the applied pressure to the MCF rubber and based on the formation of the magnetic clusters. We also explained the tendency of the electric current and the temporary thermal conductivity during the application of heat under low pressure using quantum mechanics theory and clarified the material behavior as a semiconductor based on the thermal characteristics as well as the electric characteristics.
Wegener's Granulomatosis Presenting with Pachymeningitis: Clinical and Imaging Remission by Rituximab
Authors: Just Søren Andreas , Knudsen John Bonde , Nielsen Mie Kiszka , Junker Peter
Published: June 2011

A 27-year-old woman was admitted for intractable right-sided neck, ear, and jaw pain with gradual development of tinnitus and hearing loss. A cerebral MRI showed meningo-dural enhancement, and additional diagnostic workup revealed a right pulmonary infiltrate and positive PR-3 ANCA. Biopsies from nasal mucosa and lung showed chronic inflammation with granuloma formation. Based on these findings the patient was diagnosed with Wegener's granulomatosis with pachymeningitis. There was no clinical response to oral Prednisolone and Cyclophosphamide, but complete clinical and imaging remission was achieved by adding Rituximab.
Controlled Synthesis of Hollow Hemispheric ZnO Shells/Cages on Graphite Fiber
Authors: Liu Xianbin , Du Hejun , Zeng Zhiyuan , Sun Xiao Wei
Published: June 2011

Hollow hemispheric ZnO shells/cages are synthesized on graphite fiber via simple thermal evaporation process. The cage-like ZnO structures exhibit micron or submicron size and hollow hemispheric shape with polycrystalline shell made of the ZnO nanocrystals. Controlled time-sequenced growth experiment is conducted to interpret the growth process, which indicates that the growth mechanism of the hollow hemispheric ZnO shells/cages involves formation of Zn particles firstly, followed by oxidation of the outer surface of Zn droplets and meantime sublimation of the core Zn.
On the Idempotent Solutions of a Kind of Operator Equations
Authors: Deng Chun Yuan
Published: June 2011

This paper provides some relations between the idempotent operators and the solutions to operator equations ABA=A2 and BAB=B2.
Tobacco use among firefighters in the central United States
Authors: Haddock C. Keith , Jitnarin Nattinee , Poston Walker S.C. , Tuley Brianne , Jahnke Sara A.
Published: June 2011

Background

This study provides a comprehensive, population‐based examination of tobacco use among both career and volunteer firefighters.

Methods

Data are from a population‐based cohort study of randomly selected career (N = 11) and volunteer (N = 13) departments comprised of 677 male firefighters.

Results

Unadjusted rates of smoking were 13.6% and 17.4% for career and volunteer firefighters, respectively. Smoking rates were less than a comparable occupational group (military personnel) and adult males in the states represented. Smokers were more likely to have been diagnosed with an anxiety disorder (OR = 5.8; P = 0.010), have an elevated CAGE alcohol problem score (OR = 2.9; P = 0.040), and more likely to report driving after drinking too much (OR = 4.5; P = 0.020) compared to never‐smokers. Large percentages of career (18.4%) and volunteer (16.8%) firefighters used smokeless tobacco.

Conclusions Smokin

g among firefighters is associated with other significant health and safety risks. High rates of smokeless tobacco use suggest that the fire service is an important target for intervention. Thus, despite strong statements against smoking by the fire service, the need to maintain high levels of health and fitness and relatively low smoking rates, a significant proportion of firefighters continue to use tobacco products. Am. J. Ind. Med. 54:697–706, 2011. © 2011 Wiley‐Liss, Inc.
Association between polymorphisms in catechol‐O‐methyltransferase (COMT) and cocaine‐induced paranoia in European‐American and African‐American populations
Authors: Ittiwut Rungnapa , Listman Jennifer B. , Ittiwut Chupong , Cubells Joseph F. , Weiss Roger D. , Brady Kathleen , Oslin David , Farrer Lindsay A. , Kranzler Henry R. , Gelernter Joel
Published: June 2011

Catechol‐O‐methyltransferase (genetic locus, COMT) is a major enzyme involved in catecholamine metabolism and has been associated with numerous psychiatric phenotypes. We studied COMT SNPs and haplotypes in cocaine‐induced paranoia (CIP) in African‐American (AA) and European‐American (EA) populations. We genotyped 17 SNPs across the COMT locus in 319 AA pedigrees (848 individuals) and 302 EA pedigrees (707 individuals). Family‐controlled association analyses were conducted using FBAT. We found SNP rs737865 to be nominally significantly associated in the AA family population (P = 0.05). In EAs, the best‐known marker, rs4680 (Val158Met), was nominally significant in additive models (P = 0.03). SNP rs174696 also showed nominal significance in additive models (P = 0.02). We considered the three SNPs (rs737866–rs4680–rs174696) together in haplotype analysis in both family populations, using HBAT. The A–A–T haplotype was significantly associated with CIP in EAs (Z = 2.845; P = 0.0044, global P = 0.020). We then studied COMT SNPs in an additional 738 AA and 404 EA unrelated cocaine dependent individuals with and without paranoia. The A–A–T haplotype was significantly associated to CIP in the AA unrelated population (P = 0.0015). Two haplotypes, A–G–C and A–A–C, were significant in the EA unrelated population (P = 0.001 and 0.0003). We also identified rs4680 and three other SNPs, rs933271, rs5993883, and rs740603, as potentially functional variants, as predicted by a signature of positive selection in unrelated EAs and AAs. Based on our robust family‐controlled and unrelated‐affected analyses, we conclude that COMT is associated with CIP, possibly as a result of its role in the metabolism of dopamine and norepinephrine. © 2011 Wiley‐Liss, Inc.
Student attitudes toward cadaveric dissection at a UK medical school
Authors: Quince Thelma A. , Barclay Stephen I. G. , Spear Michelle , Parker Richard A. , Wood Diana F.
Published: June 2011

A more humanistic approach toward dissection has emerged. However, student attitudes toward this approach are unknown and the influences on such attitudes are little understood. One hundred and fifty‐six first‐year medical students participated in a study examining firstly, attitudes toward the process of dissection and the personhood of the cadaver and secondly, the extent to which gender, anxiety, exposure to dissection, bereavement and prior experience of a dead body influenced these attitudes. Attitudes toward dissection were assessed by of levels of agreement toward eleven statements and by selection of adjectives describing possible feelings toward dissection. Students were asked about recent bereavement, whether they had seen a dead body prior to starting their course and exposure to dissection when completing the questionnaire. Validated instruments were used to measure disposition toward generalized anxiety (Hospital Anxiety and Depression Scale) and toward death anxiety (Collett‐Lester Death Anxiety Scale). Between 60% and 94% of students held positive attitudes toward the process of dissection and over 70% of students selected 2 or fewer negative adjectives. Students' attitudes toward the personhood of the cadaver were more disparate. Disposition toward anxiety (particularly death anxiety), and exposure to dissection, influenced attitudes. Female gender and recent bereavement exerted a negative influence. Students with higher levels of anxiety experienced more negative feelings and those recently bereaved were less enthusiastic about dissection. Anticipation of dissection may be worse than reality. Sensitive preparation of students prior to entering the dissecting room for the first time may be beneficial. Anat Sci Educ. © 2011 American Association of Anatomists.
Semaphorin 3A expression in the colon of Hirschsprung disease
Authors: Wang Li‐Li , Fan Yang , Zhou Feng‐hua , Li Hui , Zhang Yi , Miao Jia‐Ning , Gu Hui , Huang Tian‐Chu , Yuan Zheng‐Wei
Published: June 2011

BACKGROUND

Hirschsprung disease (HSCR) is a congenital disorder characterized by an absence of intrinsic ganglion cells in the nerve plexuses of the lower colon. The Semaphorin 3A (SEMA3A) gene is involved in the migration of enteric neural precursors (ENPs). To analyze the function of SEMA3A in HSCR, the SEMA3A expression in different colon segments in HSCR was examined.

METHODS

The expression levels of SEMA3A in both ganglionic and aganglionic colon tissues of 32 patients with HSCR and in colon tissue of 5 newborn unaffected individuals were examined by real‐time RT‐PCR, Western‐blot, and immunohistology.

RESULTS

Comparison of SEMA3A expression levels between ganglionic and aganglionic tissues in HSCR revealed upregulation of SEMA3A expression in 43.75% (14/32) of the aganglionic colons. SEMA3A was expressed in the ganglion cells of the myenteric plexus, submucosa, as well as in the longitudinal and circular muscle layer of the normal colon of both unaffected newborns and patients with HSCR. In the aganglionic segment of patients with HSCR, SEMA3A was highly expressed in the circular muscle layer and was also detected in the submucosa and in the longitudinal muscles layer. The fluorescence intensity of SEMA3A in the circular muscle layer in the aganglionic segment was much higher than that in ganglionic segment (p < .001).

CONCLUSION

SEMA3A expression was upregulated in the aganglionic smooth muscle layer of the colon in some patients with HSCR and our data suggest that increased SEMA3A expression may be a risk factor for HSCR pathology in a subset of patients. Birth Defects Research (Part A), 2011. © 2011 Wiley‐Liss, Inc.
Encapsulated mesenchymal stromal cells for in vivo transplantation
Authors: Barminko Jeffrey , Kim Jae Hwan , Otsuka Seiji , Gray Andrea , Schloss Rene , Grumet Martin , Yarmush Martin L.
Published: June 2011

Immunomodulatory human mesenchymal stromal cells (hMSC) have been incorporated into therapeutic protocols to treat secondary inflammatory responses post‐spinal cord injury (SCI) in animal models. However, limitations with direct hMSC implantation approaches may prevent effective translation for therapeutic development of hMSC infusion into post‐SCI treatment protocols. To circumvent these limitations, we investigated the efficacy of alginate microencapsulation in developing an implantable vehicle for hMSC delivery. Viability and secretory function were maintained within the encapsulated hMSC population, and hMSC secreted anti‐inflammatory cytokines upon induction with the pro‐inflammatory factors, TNF‐α and IFN‐γ. Furthermore, encapsulated hMSC modulated inflammatory macrophage function both in vitro and in vivo, even in the absence of direct hMSC‐macrophage cell contact and promoted the alternative M2 macrophage phenotype. In vitro, this was evident by a reduction in macrophage iNOS expression with a concomitant increase in CD206, a marker for M2 macrophages. Finally, Sprague‐Dawley rat spinal cords were injured at vertebra T10 via a weight drop model (NYU model) and encapsulated hMSC were administered via lumbar puncture 24 h post‐injury. Encapsulated hMSC localized primarily in the cauda equina of the spinal cord. Histological assessment of spinal cord tissue 7 days post‐SCI indicated that as few as 5 × 104 encapsulated hMSC yielded increased numbers of CD206‐expressing macrophages, consistent with our in vitro studies. The combined findings support the inclusion of immobilized hMSC in post‐CNS trauma tissue protective therapy, and suggest that conversion of macrophages to the M2 subset is responsible, at least in part, for tissue protection. Biotechnol. Bioeng. 2011;108: 2747–2758. © 2011 Wiley Periodicals, Inc.
Neural bases of gaze and emotion processing in children with autism spectrum disorders
Authors: Davies Mari S. , Dapretto Mirella , Sigman Marian , Sepeta Leigh , Bookheimer Susan Y.
Published: June 2011

Abnormal eye contact is a core symptom of autism spectrum disorders (ASD), though little is understood of the neural bases of gaze processing in ASD. Competing hypotheses suggest that individuals with ASD avoid eye contact due to the anxiety‐provoking nature of direct eye gaze or that eye‐gaze cues hold less interest or significance to children with ASD. The current study examined the effects of gaze direction on neural processing of emotional faces in typically developing (TD) children and those with ASD. While undergoing functional magnetic resonance imaging (fMRI), 16 high‐functioning children and adolescents with ASD and 16 TD controls viewed a series of faces depicting emotional expressions with either direct or averted gaze. Children in both groups showed significant activity in visual‐processing regions for both direct and averted gaze trials. However, there was a significant group by gaze interaction such that only TD children showed reliably greater activity in ventrolateral prefrontal cortex for direct versus averted gaze. The ASD group showed no difference between direct and averted gaze in response to faces conveying negative emotions. These results highlight the key role of eye gaze in signaling communicative intent and suggest altered processing of the emotional significance of direct gaze in children with ASD.
Epidemic of illicit drug use, mechanisms of action/addiction and stroke as a health hazard
Authors: Esse Katherine , Fossati‐Bellani Marco , Traylor Angela , Martin‐Schild Sheryl
Published: June 2011

Drug abuse robs individuals of their jobs, their families, and their free will as they succumb to addiction; but may cost even more: a life of disability or even life lost due to stroke. Many illicit drugs have been linked to major cardiovascular events and other comorbidities, including cocaine, amphetamines, ecstasy, heroin, phencyclidine, lysergic acid diethylamide, and marijuana. This review focuses on available epidemiological data, mechanisms of action, particularly those leading to cerebrovascular events, and it is based on papers published in English in PubMed during 1950 through February 2011. Each drug's unique interactions with the brain and vasculature predispose even young, healthy people to ischemic or hemorrhagic stroke. Cocaine and amphetamines have the strongest association with stroke. However, the level of evidence firmly linking other drugs to stroke pathogenesis is weak. Large epidemiological studies and systematic evaluation of each drug's action on the brain and cardiovascular system are needed to reveal the full impact of drug use on the population.
Stereodivergent Ruthenium‐Catalyzed Transfer Semihydrogenation of Diaryl Alkynes
Authors: Li Jie , Hua Ruimao
Published: June 2011

[Ru3(CO)12]‐catalyzed transfer semihydrogenation of various functionalized diaryl alkynes with N,N‐dimethylformamide (DMF) and water as hydrogen source affords cis‐ and trans‐stilbenes. The stereodivergent approach can be switched by the use of acetic (HOAc) or trifluoroacetic (TFA) acid as additives. The catalytic processes can be applied to the synthesis of analogues of natural products such as cis‐combretastatin A‐4 and trans‐resveratrol.
Intracellular Protein Labeling with Prodrug‐Like Probes Using a Mutant β‐Lactamase Tag
Authors: Watanabe Shuji , Mizukami Shin , Akimoto Yuri , Hori Yuichiro , Kikuchi Kazuya
Published: June 2011

Intracellular protein labeling with small molecular probes that do not require a washing step for the removal of excess probe is greatly desired for real‐time investigation of protein dynamics in living cells. Successful labeling of proteins on the cell membrane has been performed using mutant β‐lactamase tag (BL‐tag) technology. In the present study, intracellular protein labeling with novel cell membrane permeable probes based on β‐lactam prodrugs is described. The prodrug‐based probes quickly permeated the plasma membranes of living mammalian cells, and efficiently labeled intracellular proteins at low probe concentrations. Because these cell‐permeable probes were activated only inside cells, simultaneous discriminative labeling of intracellular and cell surface BL‐tag fusion proteins was attained by using cell‐permeable and impermeable probes. Thus, this technology enables adequate discrimination of the location of proteins labeled with the same protein tag, in conjunction with different color probes, by dual‐color fluorescence. Moreover, the combination of BL‐tag technology and the prodrug‐based probes enabled the labeling of target proteins without requiring a washing step, owing to the efficient entry of probes into cells and the fast covalent labeling achieved with BL‐tag technology after bioactivation. This prodrug‐based probe design strategy for BL‐tags provides a simple experimental procedure with application to cellular studies with the additional advantage of reduced stress to living cells.
Identification of a Higher‐Order Organozincate Intermediate Involved in Negishi Cross‐Coupling Reactions by Mass Spectrometry and NMR Spectroscopy
Authors: Hunter Howard N. , Hadei Niloufar , Blagojevic Voislav , Patschinski Pascal , Achonduh George T. , Avola Stephanie , Bohme Diethard K. , Organ Michael G.
Published: June 2011

Negishi cross‐coupling reactions were analyzed in solution by mass spectrometry and NMR spectroscopy to identify both the effect of LiBr as an additive as well as the purpose of 3‐dimethyl‐2‐imidazolidinone (DMI) as a co‐solvent. The results suggest that the main role of DMI is to facilitate a higher order bromozincate formation during the addition of LiBr.
The POU transcription factor UNC‐86 controls the timing and ventral guidance of Caenorhabditis elegans axon growth
Authors: Olsson‐Carter Katherine , Slack Frank J.
Published: June 2011

The in vivo mechanisms that coordinate the timing of axon growth and guidance are not well understood. In the Caenorhabditis elegans hermaphrodite specific neurons (HSNs), the lin‐4 microRNA controls the stage of axon initiation independent of the UNC‐40 and SAX‐3 ventral guidance receptors. lin‐4 loss‐of‐function mutants exhibit marked delays in axon outgrowth, while lin‐4 overexpression leads to precocious growth in the L3 larval stage. Here, we show that loss of the POU transcription factor UNC‐86 not only results in penetrant ventral axon growth defects in in the HSNs, but also causes processes to extend in the L1, three stages earlier than wild‐type. This temporal shift is not dependent on UNC‐40 or SAX‐3, and does not require the presence of lin‐4. We propose that unc‐86(lf) HSN axons are misguided due to the temporal decoupling of axon initiation and ventral guidance responses. Developmental Dynamics 240:1815–1825, 2011. © 2011 Wiley‐Liss, Inc.
Land cover effects on groundwater recharge in the tropics: ecohydrologic mechanisms
Authors: Brauman Kate A. , Freyberg David L. , Daily Gretchen C.
Published: June 2011

Managing groundwater recharge to ensure sufficient water supply is a growing concern for many communities. We explore land cover effects on recharge processes and rate in Hawai'i, where precipitation on the mountain slopes of leeward Hawai'i Island recharges the aquifer that is the sole source of water for coastal communities. Applying a water balance, we quantify the influences of native forest and cattle pasture on recharge using measurements of precipitation and the drivers of evapotranspiration taken over 18 months. Surface runoff is negligible in these highly permeable basalt watersheds, simplifying fluxes into and out of the recharge area. On the basis of our analysis of measured fluxes, groundwater recharge is 96% of rainfall in pasture, 87% of above‐canopy rainfall in open forest, and 106% of above‐canopy rainfall in dense forest. Differences in recharge among vegetation types result largely from direct interception of cloud water by native Hawaiian forest. The majority of rainfall occurs in infrequent, large storms, so water moves quickly beyond plant rooting depth, limiting its availability for evapotranspiration. Potential evapotranspiration is low, as its drivers are modest and constant throughout the year. Existing estimates of submarine groundwater discharge support our conclusion that the rainfall‐to‐recharge ratio is close to one for all sites. Identifying primary influences on the recharge‐to‐rainfall ratio is key to predicting the types of changes that will have substantial effects on recharge. In any tropical setting with young, porous substrates, precipitation is likely to play a dominant role in the magnitude and variability of groundwater recharge; here, land‐use changes that affect local precipitation, such as an increase in fog interception, will play a larger role than vegetation shifts that affect evapotranspiration. Copyright © 2011 John Wiley & Sons, Ltd.
Morphine‐induced mu opioid receptor trafficking enhances reward yet prevents compulsive drug use
Authors: Berger Amy Chang , Whistler Jennifer L.
Published: June 2011

Morphine, heroin and other commonly abused opioids induce little mu opioid receptor (MOR) trafficking compared to endogenous opioids. We utilized knock‐in mice expressing a mutant recycling MOR (RMOR) that desensitizes and is internalized in response to morphine to show that facilitating MOR trafficking not only enhances morphine reward but, despite this, reduces the development of addiction‐like behaviours. To demonstrate this, we developed a novel model of the transition from controlled to compulsive drug use that recapitulates many features of human addiction, including persistent drug seeking despite adverse consequences and a decreased preference for alternative rewards. These behaviours emerged spontaneously in wild‐type but not RMOR mice, and their intensity predicted the reinstatement of morphine seeking after extended abstinence, while prior morphine intake did not. These results confirm previous findings in the rat that addiction can be dissociated from both reward and consumption. Most importantly, these results demonstrate that one can simultaneously reduce the ‘addictiveness’ of morphine and enhance its desirable effects by promoting agonist‐induced MOR trafficking.
Post‐protection effect of heat‐resistant insulations on timber‐frame members exposed to fire
Authors: Just Alar , Schmid Joachim , König Jürgen
Published: June 2011

In lightweight walls and floors, the load‐bearing timber members are protected by cladding on the sides to form a divider between two fire compartments or to provide appropriate fire protection to the load‐bearing members. The spaces between the timber members can be void or filled with insulation materials. Although a huge number of different insulation materials exist, the most commonly used material is mineral wool insulation.

The existing design model for glass wool‐insulated timber‐frame constructions, given in European standard 1995‐1‐2, assumes collapse of the glass wool after failure of the cladding. However, a new form of glass wool insulation, suitable for use at high maximum service temperatures, is now available in the market. The charring phase after the cladding's failure is known as the post‐protection phase. The behaviour of the new heat‐resistant glass wool in the post‐protection phase is similar to that of stone wool and considerably better than that of traditional glass wool. The protective properties of stone wool have changed over the last decades.

Charring is one of the main parameters needed to calculate the resistance of a structure to fire. Based on experimental investigations, this paper describes the analysis of the effect of the insulation with regard to its ability to protect timber members against charring during the post‐protection phase. Copyright © 2011 John Wiley & Sons, Ltd.
Evidence for a virtual human analog of a rodent relational memory task: A study of aging and fMRI in young adults
Authors: Etchamendy Nicole , Konishi Kyoko , Pike G. Bruce , Marighetto Aline , Bohbot Véronique D.
Published: June 2011

A radial maze concurrent spatial discrimination learning paradigm consisting of two stages was previously designed to assess the flexibility property of relational memory in mice, as a model of human declarative memory. Aged mice and young adult mice with damage to the hippocampus, learned accurately Stage 1 of the task which required them to learn a constant reward location in a specific set of arms (i.e., learning phase). In contrast, they were impaired relative to healthy young adult mice in a second stage when faced with rearrangements of the same arms (i.e., flexibility probes). This mnemonic inflexibility in Stage 2 is thought to derive from insufficient relational processing by the hippocampus during initial learning (Stage 1) which favors stimulus‐response learning, a form of procedural learning. This was proposed as a model of the selective declarative and relational memory decline classically described in elderly people. As a first step to examine the validity of this model, we adapted this protocol to humans using a virtual radial‐maze. (1) We showed that performance in the flexibility probes in young and older adults positively correlated with performance in a wayfinding task, suggesting that our paradigm assesses relational memory. (2) We demonstrated that older healthy participants displayed a deficit in the performance of the flexibility probes (Stage 2), similar to the one previously seen in aged mice. This was associated with a decline in the wayfinding task. (3) Our fMRI data in young adults confirmed that hippocampal activation during early discrimination learning in Stage 1 correlated with memory flexibility in Stage 2, whereas caudate nucleus activation in Stage 1 negatively correlated with subsequent flexibility. By enabling relational memory assessment in mice and humans, our radial‐maze paradigm provides a valuable tool for translational research. © 2011 Wiley Periodicals, Inc.
Decoding representations of scenes in the medial temporal lobes
Authors: Bonnici Heidi M. , Kumaran Dharshan , Chadwick Martin J. , Weiskopf Nikolaus , Hassabis Demis , Maguire Eleanor A.
Published: June 2011

Recent theoretical perspectives have suggested that the function of the human hippocampus, like its rodent counterpart, may be best characterized in terms of its information processing capacities. In this study, we use a combination of high‐resolution functional magnetic resonance imaging, multivariate pattern analysis, and a simple decision making task, to test specific hypotheses concerning the role of the medial temporal lobe (MTL) in scene processing. We observed that while information that enabled two highly similar scenes to be distinguished was widely distributed throughout the MTL, more distinct scene representations were present in the hippocampus, consistent with its role in performing pattern separation. As well as viewing the two similar scenes, during scanning participants also viewed morphed scenes that spanned a continuum between the original two scenes. We found that patterns of hippocampal activity during morph trials, even when perceptual inputs were held entirely constant (i.e., in 50% morph trials), showed a robust relationship with participants' choices in the decision task. Our findings provide evidence for a specific computational role for the hippocampus in sustaining detailed representations of complex scenes, and shed new light on how the information processing capacities of the hippocampus may influence the decision making process. © 2011 Wiley Periodicals, Inc.
A chirality‐based metrics for free‐energy calculations in biomolecular systems
Authors: Pietropaolo Adriana , Branduardi Davide , Bonomi Massimiliano , Parrinello Michele
Published: June 2011

In this work, we exploit the chirality index introduced in (Pietropaolo et al., Proteins 2008, 70, 667) as an effective descriptor of the secondary structure of proteins to explore their complex free‐energy landscape. We use the chirality index as an alternative metrics in the path collective variables (PCVs) framework and we show in the prototypical case of the C‐terminal domain of immunoglobulin binding protein GB1 that relevant configurations can be efficiently sampled in combination with well‐tempered metadynamics. While the projections of the configurations found onto a variety of different descriptors are fully consistent with previously reported calculations, this approach provides a unifying perspective of the folding mechanism which was not possible using metadynamics with the previous formulation of PCVs. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Value of contrast‐enhanced sonography with micro flow imaging in the diagnosis of prostate cancer
Authors: Xie Shao Wei , Li Feng Hua , Li Hong Li , Du Jing , Xia Jian Guo , Fang Hua , Bo Juan Jie , Zhu Jian Shan
Published: June 2011

Background.

To evaluate the effectiveness of contrast‐enhanced sonographic micro flow imaging (MFI) in the diagnosis of prostate cancer.

Methods.

A total of 74 patients referred for prostate biopsy were prospectively evaluated with MFI. The abnormalities were categorized into four patterns: pattern 1: indistinct separation between the inner and outer gland; pattern 2: asymmetrical or focally increased enhancement in the outer gland; pattern 3: enhancement with focal defect; pattern 4: enhancement in the outer gland equal to that of the inner gland. The findings were correlated with Gleason scores.

Results.

Prostate cancer was detected in 264 sites in 41 patients. The sensitivity, specificity, accuracy, and positive and negative predictive values for MFI were 81.1%, 84.3%, 83.3%, 68.6%, and 91.3%, respectively. Positive predictive values for the four patterns were 46.0 (pattern 1), 53.6 (pattern 2), 94.3 (pattern 3), and 95.4 (pattern 4). Gleason scores of cancers with patterns 3 (7.09) or 4 (7.51) were significantly higher than those with patterns 1 (6.17) or 2 (6.59) (p = 0.001, p = 0.005, p < 0.001, p < 0.001).

Conclusions.

Some MFI patterns had high positive predictive values and were associated with more aggressive cancers. This could be used to reduce the number of biopsy sites and detect clinically significant cancers. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound, 2011
Symptomatic plantar fibroma with a unique sonographic appearance
Authors: Haun Daniel W. , Cho John C.S. , Kettner Norman W.
Published: June 2011

We present a case of a solitary plantar fibroma with unique sonographic features with MRI and pathologic correlation. A 25‐year‐old woman presented with a left foot mass that interfered with her gait. Sonography demonstrated a well‐circumscribed, 32 mm × 27 mm × 14 mm subcutaneous mass with heterogeneous echogenicity. Unique sonographic characteristics included posterior acoustic enhancement, cystic components, and mild intratumoral hypervascularity. MRI confirmed the sonographic findings. Surgical excision was performed without complication. A pathologic diagnosis of fibroma with myxoid degeneration and cyst formation was made. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound 40:114–112, 2012
Synthesis of heterocyclic derivatives of alkyl 2‐(cyanomethyl)‐4‐methyl‐3‐quinolinecarboxylates
Authors: Degtyarenko Alexey S. , Tolmachev Andrey A. , Volovenko Yulian M.
Published: June 2011

The article reports reactions of a series of known alkyl 2‐(cyanomethyl)‐4‐methyl‐3‐quinolinecarboxylates. In the course of the present study the synthesis of new heterocyclic derivatives of alkyl 2‐(cyanomethyl)‐4‐methyl‐3‐quinolinecarboxylates was achieved. J. Heterocyclic Chem., (2011).