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Study Design: Multicenter, international prospective study., Objective: This study investigated the clinical outcome up to 2 years after multi-level spinal deformity surgery in the elderly by reporting the minimal clinically important difference (MCID) of EuroQol 5-dimensions (EQ-5D), EQ-VAS, and residential status., Methods: As an ancillary study of 219 patients ≥60 years with spinal deformity undergoing primary instrumented fusion surgery of ≥5 levels, this study focuses on EQ-5D (3-L) as the primary outcome and EQ-VAS and residential status as secondary outcomes. Data on EQ-5D were compared between pre-operatively and postoperatively at 10 weeks, 12 months, and 24 months. An anchor-based approach was used to calculate the MCID., Results: The EQ-5D index and EQ-VAS, respectively, improved significantly at each time point compared to pre-operatively (from .53 (SD .21) and 55.6 (SD 23.0) pre-operatively to .64 (SD .18) and 65.8 (SD 18.7) at 10 weeks, .74 (SD .18) and 72.7 (SD 18.1) at 12 months, and .73 (SD .20) and 70.4 (SD 20.4) at 24 months). 217 (99.1%) patients lived at home pre-operatively, while 186 (88.6%), 184 (98.4%), and 172 (100%) did so at 10 weeks, 12 months, and 24 months, respectively. Our calculated MCID for the EQ-5D index at 1 year was .22 (95% CI .15-.29)., Conclusions: The EQ-5D index significantly increased at each time point over 24 months after ≥5 level spinal deformity surgery in elderly patients. The MCID of the EQ-5D-3 L was .22. Patients living at home pre-operatively can expect to be able to live at home 2 years postoperatively., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Study Design: A single centre retrospective review., Objective: Recent studies have suggested that distal lordosis (L4-S1, DL) remains constant across all pelvic incidence (PI) subgroups, whilst proximal lordosis (L1-L4, PL) varies. We sought to investigate the impact of post-operative DL on adjacent segment disease (ASD) requiring reoperation in patients undergoing lumbar fusion for degenerative conditions., Methods: Patients undergoing 1-3 level lumbar fusion with the two senior authors between 2007-16 were included. Demographic and radiographic data were recorded. Univariate, multivariate binary logistic regression, and Kaplan Meier survivorship analyses were performed., Results: 335 patients were included in the final analysis. Most had single (67%) or two (31%) level fusions. The mean follow-up was 64-month. Fifty-seven patients (17%) underwent reoperation for ASD at an average of 78-month post-operatively (R group). The R group had a significantly lower mean post-operative DL (27.3 vs 31.1 deg, P < .001) and mean PI (55.5 vs 59.2 deg, P < .05). On univariate analysis, patients with a post-operative DL of <35 deg had higher odds of reoperation for ASD than those with a post-operative DL of ≥35 deg (OR 2.7, P = .016). In the multivariate model, post-operative DL, low/average PI, and spondylolisthesis were all significantly associated with reoperation for ASD., Conclusion: This study provides preliminary support to an association between post-operative distal lumbar lordosis and risk of reoperation for ASD in patients undergoing fusions for degenerative conditions. Further multicentre prospective study is needed to independently confirm this association and identify the impact of restoration of physiological distal lumbar lordosis on long term patient outcomes., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The OH-initiated photo-oxidation of piperidine and the photolysis of 1-nitrosopiperidine were investigated in a large atmospheric simulation chamber and in theoretical calculations based on CCSD(T*)-F12a/aug-cc-pVTZ//M062X/aug-cc-pVTZ quantum chemistry results and master equation modeling of the pivotal reaction steps. The rate coefficient for the reaction of piperidine with OH radicals was determined by the relative rate method to be k OH-piperidine = (1.19 ± 0.27) × 10 -10 cm 3 molecule -1 s -1 at 304 ± 2 K and 1014 ± 2 hPa. Product studies show the piperidine + OH reaction to proceed via H-abstraction from both CH 2 and NH groups, resulting in the formation of the corresponding imine (2,3,4,5-tetrahydropyridine) as the major product and in the nitramine (1-nitropiperidine) and nitrosamine (1-nitrosopiperidine) as minor products. Analysis of 1-nitrosopiperidine photolysis experiments under natural sunlight conditions gave the relative rates j rel = j 1-nitrosoperidine / j NO 2 = 0.342 ± 0.007, k 3 / k 4a = 0.53 ± 0.05 and k 2 / k 4a = (7.66 ± 0.18) × 10 -8 that were subsequently employed in modeling the piperidine photo-oxidation experiments, from which the initial branchings between H-abstraction from the NH and CH 2 groups, k N-H / k tot = 0.38 ± 0.08 and k C 2 -H / k tot = 0.49 ± 0.19, were derived. All photo-oxidation experiments were accompanied by particle formation that was initiated by the acid-base reaction of piperidine with nitric acid. Primary photo-oxidation products including both 1-nitrosopiperidine and 1-nitropiperidine were detected in the particles formed. Quantum chemistry calculations on the OH initiated atmospheric photo-oxidation of piperidine suggest the branching in the initial H-abstraction routes to be ∼35% N 1 , ∼50% C 2 , ∼13% C 3 , and ∼2% C 4 . The theoretical study produced an atmospheric photo-oxidation mechanism, according to which H-abstraction from the C 2 position predominantly leads to 2,3,4,5-tetrahydropyridine and H-abstraction from the C 3 position results in ring opening followed by a complex autoxidation, of which the first few steps are mapped in detail. H-abstraction from the C 4 position is shown to result mainly in the formation of piperidin-4-one and 2,3,4,5-tetrahydropyridin-4-ol, whereas H-abstraction from N 1 under atmospheric conditions primarily leads to 2,3,4,5-tetrahydropyridine and in minor amounts of 1-nitrosopiperidine and 1-nitropiperidine. The calculated rate coefficient for the piperidine + OH reaction agrees with the experimental value within 35%, and aligning the theoretical numbers to the experimental value results in k (T) = 2.46 × 10 -12 × exp(486 K/T) cm 3 molecule -1 s -1 (200-400 K).

Photoredox catalysis is a valuable tool in a large variety of chemical reactions. Main challenges still to be overcome are photodegradation of photocatalysts and substrates, short lifetimes of reactive intermediates, and selectivity issues due to unwanted side reactions. A potential solution to these challenges is the pre-organization of the photosensitizer, substrate and (co)-catalyst in supramolecular self-assembled structures. In such architectures, (organic) dyes can be stabilized, and higher selectivity could potentially be achieved through pre-organizing desired reaction partners via non-covalent interactions. Perylene diimide (PDI) is an organic dye, which can be readily reduced to its mono- and dianion. Excitation of both anions leads to highly reducing excited states, which are able to reduce a variety of substrates via single electron transfer. The incorporation of PDI into a heteroleptic [M 4 L a 2 L b 2 ] supramolecular square has been recently demonstrated. Herein we investigate its photophysical properties and demonstrate that incorporated PDI indeed features photocatalytic activity. Initial results suggest that the pre-organisation by binding positively affects the outcome.

Because sunlight is the most abundant energy source on earth, it has huge potential for practical applications ranging from sustainable energy supply to light driven chemistry. From a chemical perspective, excited states generated by light make thermodynamically uphill reactions possible, which forms the basis for energy storage into fuels. In addition, with light, open-shell species can be generated which open up new reaction pathways in organic synthesis. Crucial are photosensitizers, which absorb light and transfer energy to substrates by various mechanisms, processes that highly depend on the distance between the molecules involved. Supramolecular coordination cages are well studied and synthetically accessible reaction vessels with single cavities for guest binding, ensuring close proximity of different components. Due to high modularity of their size, shape, and the nature of metal centers and ligands, cages are ideal platforms to exploit preorganization in photocatalysis. Herein we focus on the application of supramolecular cages for photocatalysis in artificial photosynthesis and in organic photo(redox) catalysis. Finally, a brief overview of immobilization strategies for supramolecular cages provides tools for implementing cages into devices. This review provides inspiration for future design of photocatalytic supramolecular host-guest systems and their application in producing solar fuels and complex organic molecules.

This comment addresses a systematic error in the potential energy surfaces of the title reactions presented in the original article by Alkorta et al. The NO 3 radical has D 3h symmetry in the electronic ground state while the M08HX functional employed in the original article predicts an incorrect C 2v geometry and energy. By combining thermodynamic data for the OH + HNO 3 → H 2 O + NO 3 reaction with spectroscopic data and results from M08HX calculations on HNO 3 , H 2 O and the OH radical, the ground state NO 3 radical energy is estimated to be 37 kJ mol -1 lower than reported for the C 2v geometry.

The OH-initiated photo-oxidation of N -methylmethanimine, CH 3 N═CH 2 , was investigated in the 200 m 3 EUPHORE atmospheric simulation chamber and in a 240 L stainless steel photochemical reactor employing time-resolved online FTIR and high-resolution PTR-ToF-MS instrumentation and in theoretical calculations based on quantum chemistry results and master equation modeling of the pivotal reaction steps. The quantum chemistry calculations forecast the OH reaction to primarily proceed via H-abstraction from the ═CH 2 group and π-system C-addition, whereas H-abstraction from the -CH 3 group is a minor route and forecast that N-addition can be disregarded under atmospheric conditions. Theoretical studies of CH 3 N═CH 2 photolysis and the CH 3 N═CH 2 + O 3 reaction show that these removal processes are too slow to be important in the troposphere. A detailed mechanism for OH-initiated atmospheric degradation of CH 3 N═CH 2 was obtained as part of the theoretical study. The photo-oxidation experiments, obstructed in part by the CH 3 N═CH 2 monomer-trimer equilibrium, surface reactions, and particle formation, find CH 2 ═NCHO and CH 3 N═CHOH/CH 2 ═NCH 2 OH as the major primary products in a ratio 18:82 ± 3 (3σ-limit). Alignment of the theoretical results to the experimental product distribution results in a rate coefficient, showing a minor pressure dependency under tropospheric conditions and that can be parametrized k ( T ) = 5.70 × 10 -14 × ( T /298 K) 3.18 × exp(1245 K/ T ) cm 3 molecule -1 s -1 with k 298 = 3.7 × 10 -12 cm 3 molecule -1 s -1 . The atmospheric fate of CH 3 N═CH 2 is discussed, and it is concluded that, on a global scale, hydrolysis in the atmospheric aqueous phase to give CH 3 NH 2 + CH 2 O will constitute a dominant loss process. N 2 O will not be formed in the atmospheric gas phase degradation, and there are no indications of nitrosamines and nitramines formed as primary products.

Background Context: Patients with adult spinal deformity suffer from disease related disability as measured by the Oswestry Disability Index (ODI) for which surgery can result in significant improvements., Purpose: The purpose of this study was to show the change in overall and individual components of the ODI in patients aged 60 years or older following multi-level spinal deformity surgery., Study Design: Prospective, multicenter, multi-continental, observational longitudinal cohort study PATIENT SAMPLE: Patients ≥60 years undergoing primary spinal fusion surgery of ≥5 levels for coronal, sagittal or combined deformity., Outcome Measures: Oswestry Disability Index (ODI) METHODS: : Patients completed the ODI pre-operatively for baseline, then at 10 weeks, 12 months and 24 months post-operatively. ODI scores were grouped into deciles, and change was calculated with numerical score and improvement or worsening was further categorized from baseline as substantial (≥20%), marginal (≥10-<20%) or no change (within 10%)., Results: Two-hundred nineteen patients met inclusion criteria for the study. The median number of spinal levels fused was 9 [Q1=5.0, Q3=12.0]. Two-year mean (95% CI) ODI improvement was 19.3% (16.7%; 21.9%; p<.001) for all age groups, with mean scores improved from a baseline of 46.3% (44.1%; 48.4%) to 41.1% (38.5%; 43.6%) at 10 weeks (p<.001), 28.1% (25.6%; 30.6%) at 12 months (p<.001), and 27.0% (24.4%; 29.5%) at 24 months (p<.001). At 2 years, 45.5% of patients showed 20% or greater improvement in ODI, 23.7% improved between 10% and 20%, 26.3% reported no change (defined as±10% from baseline), 4.5% of patients reported a worsening between 10% to 20%, and none reported worsening greater than 20%. 59.0% of patients were severely disabled (ODI >40%) pre-operatively, which decreased to 20.2% at 2 years. Significant improvement was observed across all 10 ODI items at 12 and 24 months. The largest improvements were seen in pain, walking, standing, sex life, social life and traveling., Conclusions: In this prospective, multicenter, multi-continental study of patients 60 years or older undergoing multi-level spinal deformity surgery, almost 70% of patients reported significant improvements in ODI without taking into account surgical indications, techniques or complications. Clear data is presented demonstrating the particular change from baseline for each decile of pre-operative ODI score, for each sub-score, and for each age group., (Copyright © 2021. Published by Elsevier Inc.)

The OH-initiated degradation of 2-amino-2-methyl-1-propanol [CH 3 C(NH 2 )(CH 3 )CH 2 OH, AMP] was investigated in a large atmospheric simulation chamber, employing time-resolved online high-resolution proton-transfer reaction-time-of-flight mass spectrometry (PTR-ToF-MS) and chemical analysis of aerosol online PTR-ToF-MS (CHARON-PTR-ToF-MS) instrumentation, and by theoretical calculations based on M06-2X/aug-cc-pVTZ quantum chemistry results and master equation modeling of the pivotal reaction steps. The quantum chemistry calculations reproduce the experimental rate coefficient of the AMP + OH reaction, aligning k ( T ) = 5.2 × 10 -12 × exp (505/ T ) cm 3 molecule -1 s -1 to the experimental value k exp,300K = 2.8 × 10 -11 cm 3 molecule -1 s -1 . The theoretical calculations predict that the AMP + OH reaction proceeds via hydrogen abstraction from the -CH 3 groups (5-10%), -CH 2 - group, (>70%) and -NH 2 group (5-20%), whereas hydrogen abstraction from the -OH group can be disregarded under atmospheric conditions. A detailed mechanism for atmospheric AMP degradation was obtained as part of the theoretical study. The photo-oxidation experiments show 2-amino-2-methylpropanal [CH 3 C(NH 2 )(CH 3 )CHO] as the major gas-phase product and propan-2-imine [(CH 3 ) 2 C═NH], 2-iminopropanol [(CH 3 )(CH 2 OH)C═NH], acetamide [CH 3 C(O)NH 2 ], formaldehyde (CH 2 O), and nitramine 2-methyl-2-(nitroamino)-1-propanol [AMPNO 2 , CH 3 C(CH 3 )(NHNO 2 )CH 2 OH] as minor primary products; there is no experimental evidence of nitrosamine formation. The branching in the initial H abstraction by OH radicals was derived in analyses of the temporal gas-phase product profiles to be B CH 3 / B CH 2 / B NH 2 = 6:70:24. Secondary photo-oxidation products and products resulting from particle and surface processing of the primary gas-phase products were also observed and quantified. All the photo-oxidation experiments were accompanied by extensive particle formation that was initiated by the reaction of AMP with nitric acid and that mainly consisted of this salt. Minor amounts of the gas-phase photo-oxidation products, including AMPNO 2 , were detected in the particles by CHARON-PTR-ToF-MS and GC×GC-NCD. Volatility measurements of laboratory-generated AMP nitrate nanoparticles gave Δ vap H = 80 ± 16 kJ mol -1 and an estimated vapor pressure of (1.3 ± 0.3) × 10 -5 Pa at 298 K. The atmospheric chemistry of AMP is evaluated and a validated chemistry model for implementation in dispersion models is presented.

The OH-initiated photo-oxidation of piperazine and 1-nitropiperazine as well as the photolysis of 1-nitrosopiperazine were investigated in a large atmospheric simulation chamber. The rate coefficient for the reaction of piperazine with OH radicals was determined by the relative rate method to be k OH-piperazine = (2.8 ± 0.6) × 10 -10 cm 3 molecule -1 s -1 at 307 ± 2 K and 1014 ± 2 hPa. Product studies showed the piperazine + OH reaction to proceed both via C-H and N-H abstraction, resulting in the formation of 1,2,3,6-tetrahydropyrazine as the major product and in 1-nitropiperazine and 1-nitrosopiperazine as minor products. The branching in the piperazinyl radical reactions with NO, NO 2 , and O 2 was obtained from 1-nitrosopiperazine photolysis experiments and employed analyses of the 1-nitropiperazine and 1-nitrosopiperazine temporal profiles observed during piperazine photo-oxidation. The derived initial branching between N-H and C-H abstraction by OH radicals, k N-H /( k N-H + k C-H ), was 0.18 ± 0.04. All experiments were accompanied by substantial aerosol formation that was initiated by the reaction of piperazine with nitric acid. Both primary and secondary photo-oxidation products including 1-nitropiperazine and 1,4-dinitropiperazine were detected in the aerosol particles formed. Corroborating atmospheric photo-oxidation schemes for piperazine and 1-nitropiperazine were derived from M06-2X/aug-cc-pVTZ quantum chemistry calculations and master equation modeling of the pivotal reaction steps. The atmospheric chemistry of piperazine is evaluated, and a validated chemical mechanism for implementation in dispersion models is presented.

Our purpose was to evaluate whether the position of a thermoluminescent dosimeter (TLD) crystal results in different exposure readings. Methods: Nine subjects wore 2 TLD badges (one facing inward, toward the palm, and one facing outward) for 2 mo. Both TLDs were worn on the middle finger of the dominant hand, with the inward-facing TLD placed at the bottom and the outward-facing TLD at the top. At the end of the first month, these TLDs were replaced with new ones for another month. Combined results from the badges for the 2 mo were recorded in millisieverts. A paired t test with 2-sample means was performed to compare the 2 positions in general nuclear medicine and PET/CT subjects, with an α of 0.05. Results: For all subjects and for the general nuclear medicine and PET/CT groups, mean exposure was greater for the inward-facing TLD. Conclusion: For a TLD worn on the dominant hand, extremity-exposure readings are maximized when the TLD faces inward., (© 2020 by the Society of Nuclear Medicine and Molecular Imaging.)

Human activity has led to increased atmospheric concentrations of many gases, including halocarbons, and may lead to emissions of many more gases. Many of these gases are, on a per molecule basis, powerful greenhouse gases, although at present-day concentrations their climate effect is in the so-called weak limit (i.e., their effect scales linearly with concentration). We published a comprehensive review of the radiative efficiencies (RE) and global warming potentials (GWP) for around 200 such compounds in 2013 (Hodnebrog et al., 2013, https://doi.org/10.1002/rog.20013). Here we present updated RE and GWP values for compounds where experimental infrared absorption spectra are available. Updated numbers are based on a revised "Pinnock curve", which gives RE as a function of wave number, and now also accounts for stratospheric temperature adjustment (Shine & Myhre, 2020, https://doi.org/10.1029/2019MS001951). Further updates include the implementation of around 500 absorption spectra additional to those in the 2013 review and new atmospheric lifetimes from the literature (mainly from WMO (2019)). In total, values for 60 of the compounds previously assessed are based on additional absorption spectra, and 42 compounds have REs which differ by >10% from our previous assessment. New RE calculations are presented for more than 400 compounds in addition to the previously assessed compounds, and GWP calculations are presented for a total of around 250 compounds. Present-day radiative forcing due to halocarbons and other weak absorbers is 0.38 [0.33-0.43] W m -2 , compared to 0.36 [0.32-0.40] W m -2 in IPCC AR5 (Myhre et al., 2013, https://doi.org/10.1017/CBO9781107415324.018), which is about 18% of the current CO 2 forcing., (©2020. The Authors.)

The reaction of CH 3 NC with OH radicals was studied in smog chamber experiments employing PTR-ToF-MS and long-path FTIR detection. The rate coefficient was determined to be k CH 3 NC+OH = (7.9 ± 0.6) × 10 -11 cm 3 molecule -1 s -1 at 298 ± 3 K and 1013 ± 10 hPa; methyl isocyanate was the sole observed product of the reaction. The experimental results are supported by CCSD(T*)-F12a/aug-cc-pVTZ//M06-2X/aug-cc-pVTZ quantum chemistry calculations showing the reaction to proceed primarily via electrophilic addition to the isocyanide carbon atom. On the basis of the quantum chemical data, the kinetics of the OH reaction was simulated using a master equation model revealing the rate coefficient to be nearly independent of pressure at tropospheric conditions and having a negative temperature dependence with k OH = 4.2 × 10 -11 cm 3 molecule -1 s -1 at 298 K. Additional quantum chemistry calculations on the CH 3 NC reactions with O 3 and NO 3 show that these reactions are of little importance under atmospheric conditions. The atmospheric fate of methyl isocyanide is discussed.

Study Design: Retrospective case study on prospectively collected data., Objectives: The purpose of this explorative study was: 1) to determine if patterns of spinal cord injury could be detected through intra-operative neuromonitoring (IONM) changes in pediatric patients undergoing spinal deformity corrections, 2) to identify if perfusion based or direct trauma causes of IONM changes could be distinguished, 3) to observe the effects of the interventions performed in response to these events, and 4) to attempt to identify different treatment algorithms for the different causes of IONM alerts., Methods: Prospectively collected neuromonitoring data in pre-established forms on consecutive pediatric patients undergoing coronal spinal deformity surgery at a single center was reviewed. Real-time data was collected on IONM alerts with >50% loss in signal. Patients with alerts were divided into 2 groups: unilateral changes (direct cord trauma), and bilateral MEP changes (cord perfusion deficits)., Results: A total of 97 pediatric patients involving 71 females and 26 males with a mean age of 14.9 (11-18) years were included in this study. There were 39 alerts in 27 patients (27.8% overall incidence). All bilateral changes responded to a combination of transfusion, increasing blood pressure, and rod removal. Unilateral changes as a result of direct trauma, mainly during laminotomies for osteotomies, improved with removal of the causative agent. Following corrective actions in response to the alerts, all cases were completed as planned. Signal returned to near baseline in 20/27 patients at closure, with no new neurological deficits in this series., Conclusion: A high incidence of alerts occurred in this series of cases. Dividing IONM changes into perfusion-based vs direct trauma directed treatment to the offending cause, allowing for safe corrections of the deformities. Patients did not need to recover IONM signal to baseline to have a normal neurological examination., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Our rationale was to evaluate how the qualities of nuclear medicine technology (NMT) programs and graduates associate with employability. Methods: We identified all Nuclear Medicine Technology Certification Board applicants who passed the entry-level NMT examination between 2012 and 2017. Certificants were e-mailed a survey with questions on graduate qualities, program qualities, and initial employment. Each quality was quantified. Age, sex, and desired employment within or outside the United States were also documented. An employability scale was created from the initial employment questions. Subjects were separated into 4 employability groups based on their employability score: poorly employable, marginally employable, satisfactorily employable, and optimally employable. An ANOVA test was performed on each quality using the 4 employability groups; a P value of less than 0.05 was considered significant. Results: Of the 3,930 surveys distributed, 885 (22.5%) were completed and returned. Six of the 10 qualities evaluated were significantly associated with employability: overall education ( P < 0.01), number of clinic hours ( P < 0.01), grade-point average ( P < 0.01), number of schools within a 100-mile (161-km) radius ( P < 0.01), number of attempts to pass the board examination ( P < 0.01), and number of clinics ( P = 0.04). The qualities that were not statistically significant were age, sex, employment location sought, board score, single versus dual certification, program level of education, and number of graduates in the class. Conclusion: There are multiple graduate and program qualities that are predictive of the employability of NMT graduates., (© 2019 by the Society of Nuclear Medicine and Molecular Imaging.)

It has become common for nuclear medicine technologists to assume the responsibilities, or even the role, of the radiation safety officer or associate radiation safety officer. Their responsibilities are primarily related to the radioactive materials license but increasingly can include additional safety responsibilities within the hospital. These include CT, MRI, and fluoroscopy safety. Many technologists reading this article may be interested in sitting for the radiation safety advanced certification examination by the Nuclear Medicine Technology Certification Board. A consultation of the content outline for that examination (found on the Nuclear Medicine Technology Certification Board website) is a good place to start. The content outline is quite extensive and cannot be covered within a single article., (© 2018 by the Society of Nuclear Medicine and Molecular Imaging.)

The OH-initiated atmospheric degradation of tert-butylamine (tBA), (CH 3 ) 3 CNH 2 , was investigated in a detailed quantum chemistry study and in laboratory experiments at the European Photoreactor (EUPHORE) in Spain. The reaction was found to mainly proceed via hydrogen abstraction from the amino group, which in the presence of nitrogen oxides (NO x ), generates tert-butylnitramine, (CH 3 ) 3 CNHNO 2 , and acetone as the main reaction products. Acetone is formed via the reaction of tert-butylnitrosamine, (CH 3 ) 3 CNHNO, and/or its isomer tert-butylhydroxydiazene, (CH 3 ) 3 CN═NOH, with OH radicals, which yield nitrous oxide (N 2 O) and the (CH 3 ) 3 Ċ radical. The latter is converted to acetone and formaldehyde. Minor predicted and observed reaction products include formaldehyde, 2-methylpropene, acetamide and propan-2-imine. The reaction in the EUPHORE chamber was accompanied by strong particle formation which was induced by an acid-base reaction between photochemically formed nitric acid and the reagent amine. The tert-butylaminium nitrate salt was found to be of low volatility, with a vapor pressure of 5.1 × 10 -6 Pa at 298 K. The rate of reaction between tert-butylamine and OH radicals was measured to be 8.4 (±1.7) × 10 -12 cm 3 molecule -1 s -1 at 305 ± 2 K and 1015 ± 1 hPa.

Correction for 'The applicability of proton transfer reaction-mass spectrometry (PTR-MS) for determination of isocyanic acid (ICA) in work room atmospheres' by Mikolaj Jan Jankowski et al., Environ. Sci.: Processes Impacts, 2014, 16, 2423-2431.

Introduction: The purpose of this article is to introduce nuclear medicine technology (NMT) educators to a method of incorporating research methodologies into the curriculum. Methods: The research methodology in the NMT program at Indiana University (IU) is taught in five steps (1. Introduction to research articles and statistics 2. Mock project and individual project design 3. Data collection 4. Writing the research paper 5. Presenting the abstract and mentoring new students). These steps could be combined for programs of shorter length or with credit hour restrictions. Results: All IU NMT students (100%) presented their research abstracts as part of a continuing education program for technologists. Seventeen of twenty-five (68%) presented their abstracts at a regional professional meeting. Six of twenty-five (24%) presented their research abstracts at a national professional meeting. Three of those six (50%) received travel grants. Two students submitted their research for publication and one was successful. Conclusion: The goal of incorporating a research methodology program into the nuclear medicine program should be to introduce undergraduates to the research process and instill excitement for new technologists to continue participation in research throughout their career., (Copyright © 2017 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

FTIR/smog chamber experiments and ab initio quantum calculations were performed to investigate the atmospheric chemistry of (CF 3 ) 2 CFCN, a proposed replacement compound for the industrially important sulfur hexafluoride, SF 6 . The present study determined k(Cl + (CF 3 ) 2 CFCN) = (2.33 ± 0.87) × 10 -17 , k(OH + (CF 3 ) 2 CFCN) = (1.45 ± 0.25) × 10 -15 , and k(O 3 + (CF 3 ) 2 CFCN) ≤ 6 × 10 -24 cm 3 molecule -1 s -1 , respectively, in 700 Torr of N 2 or air diluent at 296 ± 2 K. The main atmospheric sink for (CF 3 ) 2 CFCN was determined to be reaction with OH radicals. Quantum chemistry calculations, supported by experimental evidence, shows that the (CF 3 ) 2 CFCN + OH reaction proceeds via OH addition to -C(≡N), followed by O 2 addition to -C(OH)═N·, internal H-shift, and OH regeneration. The sole atmospheric degradation products of (CF 3 ) 2 CFCN appear to be NO, COF 2 , and CF 3 C(O)F. The atmospheric lifetime of (CF 3 ) 2 CFCN is approximately 22 years. The integrated cross section (650-1500 cm -1 ) for (CF 3 ) 2 CFCN is (2.22 ± 0.11) × 10 -16 cm 2 molecule -1 cm -1 which results in a radiative efficiency of 0.217 W m -2 ppb -1 . The 100-year Global Warming Potential (GWP) for (CF 3 ) 2 CFCN was calculated as 1490, a factor of 15 less than that of SF 6 .

The purpose of this research was to evaluate the need to use heparin when preparing an UltraTag red blood cell (RBC) kit for a nuclear medicine study., Methods: Nonheparinized blood samples (n = 15) and heparinized blood samples (n = 15) were added to UltraTag RBC kits. The samples were examined for macroscopic blood clotting and microscopic platelet clumping. As a control, samples with heparin (n = 15) and without heparin (n = 15) were used to help evaluate the effectiveness of the anticoagulant properties within the UltraTag RBC kit (sodium citrate) and whether those properties played a role in preventing clots or clumps. To detect clotting, the wooden applicator stick method was used. To detect clumping, blood smears were evaluated using a light microscope. The two samples were compared for presence of clots and clumps. Fisher exact testing was used to evaluate the significance of the data., Results: For the UltraTag RBC group, 2 of the 15 nonheparinized samples clotted and none of the 15 heparinized samples clotted; for the control group, 2 of the 15 nonheparinized samples clotted and none of the 15 heparinized samples clotted. For the Ultra-Tag RBC group, 3 of the 15 nonheparinized samples clumped and 3 of the 15 heparinized samples clumped; for the control group, 15 of the 15 nonheparinized samples clumped and 10 of the 15 heparinized samples clumped., Conclusion: When heparin is not used, the Ultra-Tag RBC kit is more likely to form clots. Heparin should always be used when preparing an Ultra-Tag RBC kit for a nuclear medicine study., (© 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

The reaction rates of (CH3)2NNO and (CH3CH2)2NNO with NO3 radicals were determined relative to formaldehyde (CH2O) and ethene (CH2CH2) at 298 ± 2 K and 1013 ± 10 hPa in purified air by long path FTIR spectroscopy. The reactions are too slow to be of importance at atmospheric conditions: kNO3+(CH3)2NNO = (1.47 ± 0.23) × 10(-16) and kNO3+(CH3CH2)2NNO = (5.1 ± 0.4) × 10(-16) cm(3) molecule(-1) s(-1) (1σ error limits). Theoretical calculations, based on CCSD(T*)-F12a/aug-cc-pVTZ//M06-2X/aug-cc-pVTZ results, predict the corresponding imines as the sole primary products in nitrosamine reactions with NO3 and OH radicals.

The FTIR matrix isolation spectra of H2SO4 vapors show a group of bands with synchronous growth of their relative intensities which is independent of the water species content of the matrix layer. Their frequency positions indicate that the species they represent is H-bonded and composed of all three components (H2SO4, H2O, and SO3) involved in the vapor decomposition equilibrium of the acid molecule. Structure, stabilization energies, and vibrational frequencies of several H-bonded complexes between these components were considered in B3LYP calculations employing Dunning's correlation-consistent aug-cc-pVTZ basis sets. Correlations between spectral shifts, bond lengths, and H-bond energies were also considered. The best fitting complex is a ring structured 1:1:1 H2SO4·H2O·SO3. The indications are that the complex is formed in the vapor phase and not after deposition. The atmospheric significance may be in its ability to serve as a H-bonding nucleation center even without the presence of additional contaminants.

The kinetics of OH radical reaction with formamide was studied by the relative rate method employing proton transfer reaction-mass spectrometry detection at the European Photochemical Reactor in Valencia, Spain. The rate coefficient was determined to be (4.5 ± 0.4) × 10(-12) cm(3) molecule(-1) s(-1) at 309 ± 3 K and 1013 ± 1 hPa. Isocyanic acid was observed as the sole product. The experimental results are supported by quantum chemical calculations and kinetic simulations using a master equation model. The calculated rate coefficient is independent of pressure at tropospheric conditions and can be accurately described by an Arrhenius expression having negative activation energy. The reaction is predicted to proceed exclusively via C-H abstraction.

The infrared spectra of formic acid/argon matrix layers deposited after flowing over a drying agent show distinct new bands when compared to matrix layers deposited without going through a drying process. The new bands are assigned as due to a formic acid/carbon monoxide H-bonded complex. Several complexes of HCOOH/CO/H2O and HCOOH/CO2 composition have been characterized in B3LYP and MP2 calculations. Comparison with experimental results indicate that the best agreement is obtained for a 1:1 HCOOH-CO hydrogen bonded complex formed between formic acid and CO originating from the decomposition process HCOOH → CO + H2O. Spectral and computational evidence is presented for the formation of HCOOH/CO2 complexes as a result of the HCOOH → CO2 + H2 decomposition path.

Frozen core MP2 and DFT computations were carried out on possible configurations of 1:1 H2SO4·CH3OH and 1:1:1 H2SO4·CH3OH·H2O complexes. Minimum energy structures, stabilization energies, H-bond lengths and vibrational frequencies were calculated. The latter complex can exist in either sequential "linear" configurations involving four H-bonds or "cyclic" structures involving three H-bonds only. However, there is little difference in the energy of stabilization between these two possible forms, indicating a "cooperative effect" between the H-bonds in the latter. This effect is also evidenced by the calculated H-bond lengths. In the cyclic complex, the hydroxyl of either CH3OH or H2O may be the proton donor to the H-bond between them. Argon matrix isolation FTIR spectra of layers with various concentration ratios were recorded. In the hydroxyl stretch wavenumber regions several weak new bands were observed. Their position was found to fit best the cyclic structures. The observed red shifts exceed the corresponding calculated values. Together with the considerable observed bandwidths they are further manifestations of the cooperative effect between the H-bonds. The lower skeletal mode wavenumber regions show a number of sharper bands compatible with those previously reported for dimethyl sulfate and hydrogen methyl sulfate, indicating their formation in the vapor mixing region or at the solid matrix layer interface.

Acetaldehyde is a hazardous pollutant found in indoor and ambient air. Acetaldehyde photolysis is pressure- and wavelength-dependent with three distinct product channels. In this study, the photolysis rates of CH3CHO, CD3CDO, and CD3CHO are studied in natural tropospheric conditions using long path FTIR spectroscopy, at the European Photoreactor Facility (EUPHORE) in Valencia, Spain. The average relative photolysis rate as an average of four experiments for the fully deuterated isotopologue is j(CH3CHO)/j(CD3CDO) = 1.75 ± 0.04, and as a result of a single experiment j(CH3CHO)/j(CD3CHO) = 1.10 ± 0.10. These results, combined with our previous determination of j(CH3CHO)/j(CH3CDO) = 1.26 ± 0.03, provide mechanistic insight into the photodissociation dynamics of the photoexcited species. Despite the extensive isotopic scrambling in photoexcited acetaldehyde that has recently been reported, the position of the substitution has a clear effect on the relative photolysis rates.

The reactions of OH radicals with CH3NHCHO (N-methylformamide, MF) and (CH3)2NCHO (N,N-dimethylformamide, DMF) have been studied by experimental and computational methods. Rate coefficients were determined as a function of temperature (T = 260-295 K) and pressure (P = 30-600 mbar) by the flash photolysis/laser-induced fluorescence technique. OH radicals were produced by laser flash photolysis of 2,4-pentanedione or tert-butyl hydroperoxide under pseudo-first order conditions in an excess of the corresponding amide. The rate coefficients obtained show negative temperature dependences that can be parameterized as follows: kOH+MF = (1.3 ± 0.4) × 10(-12) exp(3.7 kJ mol(-1)/(RT)) cm(3) s(-1) and kOH+DMF = (5.5 ± 1.7) × 10(-13) exp(6.6 kJ mol(-1)/(RT)) cm(3) s(-1). The rate coefficient kOH+MF shows very weak positive pressure dependence whereas kOH+DMF was found to be independent of pressure. The Arrhenius equations given, within their uncertainty, are valid for the entire pressure range of our experiments. Furthermore, MF and DMF smog-chamber photo-oxidation experiments were monitored by proton-transfer-reaction time-of-flight mass spectrometry. Atmospheric MF photo-oxidation results in 65% CH3NCO (methylisocyanate), 16% (CHO)2NH, and NOx-dependent amounts of CH2[double bond, length as m-dash]NH and CH3NHNO2 as primary products, while DMF photo-oxidation results in around 35% CH3N(CHO)2 as primary product and 65% meta-stable (CH3)2NC(O)OONO2 degrading to NOx-dependent amounts of CH3N[double bond, length as m-dash]CH2 (N-methylmethanimine), (CH3)2NNO (N-nitroso dimethylamine) and (CH3)2NNO2 (N-nitro dimethylamine). The potential for nitramine formation in MF photo-oxidation is comparable to that of methylamine whereas the potential to form nitrosamine and nitramine in DMF photo-oxidation is larger than for dimethylamine. Quantum chemistry supported atmospheric degradation mechanisms for MF and DMF are presented. Rate coefficients and initial branching ratios calculated with statistical rate theory based on molecular data from quantum chemical calculations at the CCSD(T*)-F12a/aug-cc-pVTZ//MP2/aug-cc-pVTZ level of theory show satisfactory agreement with the experimental results. It turned out that adjustment of calculated threshold energies by 0.2 to 8.8 kJ mol(-1) lead to agreement between experimental and predicted results.

Raman spectra of 1,1-difluoro-1-silacyclohexane as a liquid, and as a solid at 78 K were recorded and depolarization data obtained. The infrared spectra of the vapour, liquid and amorphous and crystalline solids have been studied. In the low temperature IR and Raman spectra eight and three bands, respectively, were shifted a few cm(-1) when the sample crystallized. No bands vanished after crystallization in agreement with the assumption that only one conformer (chair) was present in all the states of aggregation. The compound exists in the stable chair conformation, whereas in the parent silacyclohexane a possible twist form should have more than 15 kJ mol(-1) higher energies than the chair, as derived from various calculations. The wavenumbers of the vibrational modes were calculated in the harmonic and anharmonic approximation employing B3LYP/cc-pVTZ calculations. The 27 A' and 21 A″ fundamentals were assigned on the basis of the calculations, infrared vapour contours, Raman depolarization measurements and infrared and Raman band intensities. An average, relative deviation of 1.5% was found between the observed and the anharmonic wavenumbers for the 48 modes., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The rate coefficients for the reactions of Cl((2)PJ) with methylamine (R1), dimethylamine (R2) and trimethylamine (R3) have been measured using the laser flash photolysis - resonance fluorescence technique as a function of temperature (274-435 K) and pressure (25-400 Torr N2). The experimental data are well-represented by the following temperature- and pressure-independent rate coefficients (10(10) × k/cm(3) molecule(-1) s(-1)): kR1 = 2.90 ± 0.44, kR2 = 3.89 ± 0.58, kR3 = 3.68 ± 0.55; the uncertainties are estimates of accuracy at the 95% confidence level. Potential energy surfaces (PES) for the reactions have been characterized at the MP2/cc-pVTZ level and improved single point energies of stationary points obtained in CCSD(T)-F12a calculations. The PES for all reactions are characterized by the formation of pre and post reaction complexes and submerged barriers. Rate coefficients for the reactions were calculated as a function of temperature and pressure using a master equation model based on the coupled cluster theory results. The calculated rate coefficients are in good agreement with experiment; the overall rate coefficients are relatively insensitive to variations of the barrier heights within typical chemical accuracy, but the predicted branching ratios vary significantly. The inclusion of tunnelling has no effect.

Quantum chemical methods were used to investigate the OH initiated atmospheric degradation of methanimine, CH2═NH, the major primary product in the atmospheric photo-oxidation of methylamine, CH3NH2. Energies of stationary points on potential energy surfaces of reaction were calculated using multireference perturbation theory and coupled cluster theory. The results show that hydrogen abstraction dominates over the addition route in the CH2═NH + OH reaction, and that the major primary product is HCN, while HNC and CHONH2 are minor primary products. HNC is found to react with OH exclusively via addition to the carbon atom followed by O-H scission leading to HNCO; N2O is not a product in the atmospheric photo-oxidation of HNC. Additional G4 calculations of the CH2═NH + O3 reaction show that this is too slow to be of importance at atmospheric conditions. Rate coefficients for the CH2═NH + OH and HNC + OH reactions were calculated as a function of temperature and pressure using a master equation model based on the coupled cluster theory results. The rate coefficients for OH reaction with CH2═NH and HNC at 1000 mbar and room temperature are calculated to be 3.0 × 10(-12) and 1.3 × 10(-11) cm(3) molecule(-1) s(-1), respectively. The atmospheric fate of CH2═NH is discussed and a gas phase photo-oxidation mechanism is presented.

The rates of CH3NHNO2 and (CH3)2NNO2 reaction with OH radicals were determined relative to CH3OCH3 and CH3OH at 298 ± 2 K and 1013 ± 10 hPa in purified air by long path FTIR spectroscopy, and the rate coefficients were determined to be k(OH+CH3NHNO2) = (9.5 ± 1.9) × 10(-13) and k(OH+(CH3)2NNO2) = (3.5 ± 0.7) × 10(-12) (2σ) cm(3) molecule(-1) s(-1). Ozone was found to react very slowly with the two nitramines, k(O3+nitramine) < 10(-21) cm(3) molecule(-1) s(-1). Product formation in the photo-oxidation of CH3NHNO2 and (CH3)2NNO2 was studied by FTIR, PTR-ToF-MS, and quantum chemistry calculations; the major products in the OH-initiated degradation are the corresponding imines, CH2═NH and CH3N═CH2, and N-nitro amides, CHONHNO2 and CHON(CH3)NO2. Atmospheric degradation mechanisms are presented.

In continuation of our studies of sulfuric acid H-bonded complexes of atmospheric relevance we report the infrared spectra of the matrix isolated complexes formed between trimethylamine and sulfuric acid. Evidence for proton transfer was anticipated for the present system, as trimethylamine ((CH3)3N) is of strong basic nature. However, the spectra of this system are complicated by the inevitable presence water in the vapor and in the matrix, resulting in matrix layers containing three species capable of forming H-bonded complexes. The complex formed between trimethylamine and sulfuric acid is of ionic character due to proton transfer of the H(+) proton from sulfuric acid to (CH3)3N to form a new N-H bond and the replacement of the intramolecular O-H bond in H2SO4 by a strong intermolecular N-H···O hydrogen bond. The complex is further stabilized by hydration. The skeletal modes show clear bisulfate related bands and are only slightly affected by hydration. The ν(OH) region shows a rich band scheme, best explained by a structure involving (at least) three H2O molecules. A broad spectral feature spanning the 1700-500 cm(-1) is assigned, in analogy to previous studies to a double-well potential quasi-symmetric, Zundel-like, ionic species with a (CH3)3-N···H(+)···N-(CH3)3 configuration. A band in the skeletal S═O stretch spectral region may be assigned to hydrated sulfate as its counterion.

A method is presented for the real-time quantitative determination of isocyanic acid (ICA) in air using proton transfer reaction-mass spectrometry (PTR-MS). Quantum mechanical calculations were performed to establish the ion-polar molecule reaction rate of ICA and other isocyanates. The PTR-MS was calibrated against different ICA air concentrations and humidity conditions using Fourier transform-infrared spectroscopy (FT-IR) as quantitative reference. Based on these experiments a simple humidity dependant model was derived for correction of the PTR-MS response for ICA. The corrected PTR-MS data was linearly correlated (R(2) > 0.99) with the data acquired by FT-IR. The PTR-MS instrumental limit of detection (LOD) for ICA was 2.3 ppb. Humid atmospheres resulted in LODs of 3.4 and 7.8 ppb, at an absolute humidity (AH) of 4.0 and 15.5 g m(-3), respectively. Furthermore, off-line sampling using denuder and impinger samplers using di-n-butylamine (DBA) as derivatization reagent was compared with PTR-MS measurements in a dynamically generated standard ICA atmosphere. Denuder (n = 4) and impinger (n = 4) sampling subsequent to liquid chromatography mass spectrometry (LC-MS) determination compared to corrected PTR-MS data resulted in recoveries of 79.6 (8.1% RSD) and 99.9 (9.3% RSD) %, respectively. Measurements of ICA from thermally decomposed cured 1,6-hexamethylene diisocyanate (HDI)-paint was performed using PTR-MS and denuder (n = 3) sampling. The relation between the average ICA responses using denuders (34.4 ppb) and PTR-MS (42.6 ppb) was 80.6%, which coincided well with the relative recovery obtained from the controlled laboratory experiments using dynamically generated ICA atmospheres (79.6%). The variability in ICA air concentration during the welding process (170% RSDPTR-MS) illustrated the need for real-time measurements.

We demonstrate the capabilities and properties of using Proton Transfer Reaction time-of-flight mass spectrometry (PTR-ToF-MS) to real-time monitor gaseous emissions from industrial scale amine-based carbon capture processes. The benchmark monoethanolamine (MEA) was used as an example of amines needing to be monitored from carbon capture facilities, and to describe how the measurements may be influenced by potentially interfering species in CO2 absorber stack discharges. On the basis of known or expected emission compositions, we investigated the PTR-ToF-MS MEA response as a function of sample flow humidity, ammonia, and CO2 abundances, and show that all can exhibit interferences, thus making accurate amine measurements difficult. This warrants a proper sample pretreatment, and we show an example using a dilution with bottled zero air of 1:20 to 1:10 to monitor stack gas concentrations at the CO2 Technology Center Mongstad (TCM), Norway. Observed emissions included many expected chemical species, dominantly ammonia and acetaldehyde, but also two new species previously not reported but emitted in significant quantities. With respect to concerns regarding amine emissions, we show that accurate amine quantifications in the presence of water vapor, ammonia, and CO2 become feasible after proper sample dilution, thus making PTR-ToF-MS a viable technique to monitor future carbon capture facility emissions, without conventional laborious sample pretreatment.

The rate coefficients for the reaction of OH with the alkyl amines: methylamine (MA), dimethylamine (DMA), trimethylamine (TMA), and ethylamine (EA) have been determined using the technique of pulsed laser photolysis with detection of OH by laser-induced fluorescence as a function of temperature from 298 K to ∼600 K. The rate coefficients (10(11) × k/cm(3) molecule(-1) s(-1)) at 298 K in nitrogen bath gas (typically 5-25 Torr) are: k(OH+MA) = 1.97 ± 0.11, k(OH+DMA) = 6.27 ± 0.63, k(OH+TMA) = 5.78 ± 0.48, k(OH+EA) = 2.50 ± 0.13. The reactions all show a negative temperature dependence which can be characterized as: k(OH+MA) = (1.889 ± 0.053) × 10(-11)(T/298 K)(-(0.56±0.10)), k(OH+DMA) = (6.39 ± 0.35) × 10(-11)(T/298 K)(-(0.75±0.18)), k(OH+TMA) = (5.73 ± 0.15) × 10(-11)(T/298 K)(-(0.71±0.10)), and k(OH+EA) = (2.54 ± 0.08) × 10(-11)(T/298 K)(-(0.68±0.10)). OH and OD reactions have very similar kinetics. Potential energy surfaces (PES) for the reactions have been characterized at the MP2/aug-cc-pVTZ level and improved single point energies of stationary points obtained in CCSD(T) and CCSD(T*)-F12a calculations. The PES for all reactions are characterized by the formation of pre- and post-reaction complexes and submerged barriers. The calculated rate coefficients are in good agreement with experiment; the overall rate coefficients are relatively insensitive to variations of the barrier heights within typical chemical accuracy, but the branching ratios vary significantly. The rate coefficients for the reactions of OH/OD with MA, DMA, and EA do not vary with added oxygen, but for TMA a significant reduction in the rate coefficient is observed consistent with OH recycling from a chemically activated peroxy radical. OH regeneration is pressure-dependent and is not significant at 298 K and atmospheric pressure, but the efficiency of recycling increases strongly with temperature. The PES for OH recycling have been calculated. There is evidence that the primary process in TMA photolysis at 248 nm is the loss of H atoms.

Background: There is a need for a simple and efficacious treatment for cutaneous leishmaniasis with an acceptable side-effect profile., Methods: We conducted a randomized, vehicle-controlled phase 3 trial of topical treatments containing 15% paromomycin, with and without 0.5% gentamicin, for cutaneous leishmaniasis caused by Leishmania major in Tunisia. We randomly assigned 375 patients with one to five ulcerative lesions from cutaneous leishmaniasis to receive a cream containing 15% paromomycin-0.5% gentamicin (called WR 279,396), 15% paromomycin alone, or vehicle control (with the same base as the other two creams but containing neither paromomycin nor gentamicin). Each lesion was treated once daily for 20 days. The primary end point was the cure of the index lesion. Cure was defined as at least 50% reduction in the size of the index lesion by 42 days, complete reepithelialization by 98 days, and absence of relapse by the end of the trial (168 days). Any withdrawal from the trial was considered a treatment failure., Results: The rate of cure of the index lesion was 81% (95% confidence interval [CI], 73 to 87) for paromomycin-gentamicin, 82% (95% CI, 74 to 87) for paromomycin alone, and 58% (95% CI, 50 to 67) for vehicle control (P<0.001 for each treatment group vs. the vehicle-control group). Cure of the index lesion was accompanied by cure of all other lesions except in five patients, one in each of the paromomycin groups and three in the vehicle-control group. Mild-to-moderate application-site reactions were more frequent in the paromomycin groups than in the vehicle-control group., Conclusions: This trial provides evidence of the efficacy of paromomycin-gentamicin and paromomycin alone for ulcerative L. major disease. (Funded by the Department of the Army; ClinicalTrials.gov number, NCT00606580.).

The reactions of CH(3)CH(2)NH and (CH(3)CH(2))(2)N radicals with NO have been studied using quantum chemistry methods. The results show that formation of the nitrosamines CH(3)CH(2)NHNO and (CH(3)CH(2))(2)NNO is similar and that both isolated molecules are thermally stable. The nitrosamine formation reaction is highly exothermic, and the hot CH(3)CH(2)NHNO may undergo isomerization and subsequent reaction with O(2) to form the corresponding imine, CH(3)CH═NH. Time-dependent density functional theory (TDDFT) calculations show little difference of the vertical excitation energy between the π* ← n transitions in CH(3)CH(2)NHNO and (CH(3)CH(2))(2)NNO, and both will readily photolyze under sunlight conditions.

We present an attractive new system for the specific and sensitive detection of the malaria-causing Plasmodium parasites. The system relies on isothermal conversion of single DNA cleavage-ligation events catalyzed specifically by the Plasmodium enzyme topoisomerase I to micrometer-sized products detectable at the single-molecule level. Combined with a droplet microfluidics lab-on-a-chip platform, this design allowed for sensitive, specific, and quantitative detection of all human-malaria-causing Plasmodium species in single drops of unprocessed blood with a detection limit of less than one parasite/μL. Moreover, the setup allowed for detection of Plasmodium parasites in noninvasive saliva samples from infected patients. During recent years malaria transmission has declined worldwide, and with this the number of patients with low-parasite density has increased. Consequently, the need for accurate detection of even a few parasites is becoming increasingly important for the continued combat against the disease. We believe that the presented droplet microfluidics platform, which has a high potential for adaptation to point-of-care setups suitable for low-resource settings, may contribute significantly to meet this demand. Moreover, potential future adaptation of the presented setup for the detection of other microorganisms may form the basis for the development of a more generic platform for diagnosis, fresh water or food quality control, or other purposes within applied or basic science.

The reactions of the CH(3)NH and (CH(3))(2)N radicals with NO have been studied using quantum chemistry methods to compare the formation and stability of primary and secondary nitrosamines. The calculations show that the entrance part of potential energy surfaces of CH(3)NHNO and (CH(3))(2)NNO formation are similar, and it is concluded that primary amines form nitrosamines under the atmospheric conditions. CH(3)NHNO can, in contrast to (CH(3))(2)NNO, undergo isomerization via a barrier below the reactants entrance energy to CH(2)NHNOH, which through reaction with O(2) eventually leads to formation of CH(2)=NH on a short timescale. TDDFT, CASPT2 and MR-CI calculations show little difference between the n→π* transitions in CH(3)NHNO and (CH(3))(2)NNO and that the two molecules should have comparable photolysis lifetimes in the atmosphere.

This critical review addresses the atmospheric gas phase and aqueous phase amine chemistry that is relevant to potential emissions from amine-based carbon capture and storage (CCS). The focus is on amine, nitrosamine and nitramine degradation, and nitrosamine and nitramine formation processes. A comparison between the relative importance of the various atmospheric sinks for amines, nitrosamines and nitramines is presented.

The environmentally important interaction products of trimethylamine (TMA) and water molecules have been observed by Matrix Isolation Fourier Transform Infrared Spectroscopy (MIS-FTIR). Infrared spectra of solid argon matrix layers, in which both TMA and H(2)O molecules were entrapped as impurities, were analyzed for bands in the ν(O-H) region, not seen in matrix layers containing either of the parent molecules alone. Results were interpreted on the basis of the emergence of several spectral band pairs and their red shifts from the position of the matrix isolated H(2)O monomers as compared to semiempirically scaled frequencies from the B3LYP/aug-cc-pVTZ calculations and empirical correlations with a large body of data on H-bonded complexes. Bands were assigned to a complex cluster of two TMA molecules flanking a closed ring of four H-bonded H(2)O molecules. The formation of this cluster is argued to be formed in the vapor phase (as opposed to being a result of diffusion of the trapped species) and is related to its large stabilization energy (enthalpy) because of strong cooperative effects in its H-bond system.

We present a Rolling-Circle-Enhance-Enzyme-Activity-Detection (REEAD) system with potential use for future point-of-care diagnosis of malaria. In the developed setup, specific detection of malaria parasites in crude blood samples is facilitated by the conversion of single Plasmodium falciparum topoisomerase I (pfTopI) mediated cleavage-ligation events, happening within nanometer dimensions, to micrometer-sized products readily detectable at the single molecule level in a fluorescence microscope. In principle, REEAD requires no special equipment and the readout is adaptable to simple colorimetric detection systems. Moreover, with regard to detection limit the presented setup is likely to outcompete standard gold immuno-based diagnostics. Hence, we believe the presented assay forms the basis for a new generation of easy-to-use diagnostic tools suitable for the malaria epidemic areas in developing countries.

Intake of trans-fatty acids (TFA), especially industrially produced TFA (I-TFA), has been associated with the risk of CHD through influence on serum lipid levels. Other causal pathways remain less investigated. In the present cross-sectional study of middle-aged men representing a broad range of BMI, the association between intake of TFA, I-TFA and ruminant TFA (R-TFA) and obesity-associated risk markers of CHD was assessed. The study comprised 393 Danish men (median age 49 years) with a median BMI of 28·4 kg/m(2). Intake of TFA was estimated based on 7 d dietary records, whereas outcomes of interest (waist circumference, sagittal abdominal diameter, percentage of truncal fat, C-reactive protein, IL-6, blood lipids, blood pressure, HbA1c and insulin sensitivity index) were obtained through clinical examination. The associations were assessed by linear regression analysis. The median intake of total TFA among the 393 men was 1·3 g/d, covering a daily I-TFA intake of 0·4 g (10-90th percentile 0·0-1·0) and R-TFA intake of 0·9 g (10-90th percentile 0·4-1·8). Intake of these amounts of TFA showed no significant associations with abdominal fatness, inflammatory markers, blood lipids, blood pressure and insulin homeostasis. Among middle-aged men with a generally low intake of TFA, neither I-TFA nor R-TFA was significantly related to obesity-associated risk markers of CHD. The decreased average intake of I-TFA in Denmark since 1995 is suggested to effectively prevent occurrence of the adverse metabolic changes and health consequences, which have formerly been observed in relation to, especially, I-TFA intake.