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We applied reaction microscopy to elucidate fast non-adiabatic dissociation dynamics of deuterated water molecules after direct photo-double ionization at 61 eV with synchrotron radiation. For the very rare D+ + O+ + D breakup channel, the particle momenta, angular, and energy distributions of electrons and ions, measured in coincidence, reveal distinct electronic dication states and their dissociation pathways via spin-orbit coupling and charge transfer at crossings and seams on the potential energy surfaces. Notably, we could distinguish between direct and fast sequential dissociation scenarios. For the latter case, our measurements reveal the geometry and orientation of the deuterated water molecule with respect to the polarization vector that leads to this rare 3-body molecular breakup channel. Aided by multi-reference configuration-interaction calculations, the dissociation dynamics could be traced on the relevant potential energy surfaces and particularly their crossings and seams. This approach also unraveled the ultrafast time scales governing these processes.
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We present an investigation of the relaxation dynamics of deuterated water molecules after direct photo-double ionization at 61 eV. We focus on the very rare D+ + O+ + D reaction channel in which the sequential fragmentation mechanisms were found to dominate the dynamics. Aided by theory, the state-selective formation and breakup of the transient OD+(a1Δ, b1Σ+) is traced, and the most likely dissociation path-OD+: a1Δ or b1Σ+ â A 3Π â X 3Σ- â B 3Σ--involving a combination of spin-orbit and non-adiabatic charge transfer transitions is determined. The multi-step transition probability of this complex transition sequence in the intermediate fragment ion is directly evaluated as a function of the energy of the transient OD+ above its lowest dissociation limit from the measured ratio of the D+ + O+ + D and competing D+ + D+ + O sequential fragmentation channels, which are measured simultaneously. Our coupled-channel time-dependent dynamics calculations reproduce the general trends of these multi-state relative transition rates toward the three-body fragmentation channels.
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We present the relaxation dynamics of deuterated water molecules via autoionization, initiated by the absorption of a 61 eV photon, producing the very rare D+ + O+ + D breakup channel. We employ the COLd target recoil ion momentum spectroscopy method to measure the 3D momenta of the ionic fragments and emitted electrons from the dissociating molecule in coincidence. We interpret the results using the potential energy surfaces extracted from multi-reference configuration interaction calculations. The measured particle energy distributions can be related to a super-excited monocationic state located above the double ionization threshold of D2O. The autoionized electron energy shows a sharp distribution centered around 0.5 eV, which is a signature of the atomic oxygen autoionization occurring in the direct and sequential dissociation processes of D2O+* at a large internuclear distance. In this way, an O+ radical fragment and a low-energy electron are created, both of which can trigger secondary reactions in their environment.
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After their application in agricultural areas, pesticides are dispersed throughout the environment, causing contamination problems. In Argentina, the main promoter of transgenic biotechnology in the region, the total consumption of agrochemicals has increased significantly in recent years. Most chemicals dumped near surface waters eventually end up in bottom sediments and can be toxic to the organisms that live there. However, published data on the mixing of pesticides in this compartment is still scarce. The objective of this work was to detect and quantify pesticide residues in the sediment of rural streams in the Pampas region and to carry out acute and chronic risk assessment in these aquatic ecosystems. The study area comprises the mountainous system of Tandilia, located in one of the most productive agricultural areas in the country. The concentration of atrazine, acetochlor, chlorpyrifos, cypermethrin, and 2,4-D in the sediment of four rural streams was determined in three different seasons, and the toxic units (TU) and the risk ratios (RQ) were calculated. All the compounds analyzed were detected in most of the sampling seasons and study sites, at concentrations higher than those established in the national and international quality guidelines for the protection of aquatic biota in surface waters and for human consumption. Chlorpyrifos, cypermethrin, and acetochlor were the main pesticides contributing to the TU and RQ values, representing a medium or high ecological risk in most of the sites. Therefore, the evaluation of these pesticides in the bottom sediments could be a decisive factor in assessing the risk to the aquatic environment.
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Clorpirifos , Praguicidas , Poluentes Químicos da Água , Humanos , Praguicidas/análise , Ecossistema , Rios/química , Argentina , Poluentes Químicos da Água/análise , Medição de Risco , Monitoramento Ambiental , Sedimentos Geológicos/químicaRESUMO
In this paper, two medusa-like ACyDs, modified at the primary rim bearing four (ACyD4) and eight carbons (ACyD8) acyl chain length, and one bouquet-like CyD, modified at primary side with thiohexyl and at secondary one with oligoethylene moiety (SC6OH), were investigated for their ability to assemble in nanostructures or to form hybrid dipalmitoylphosphatidylcholine (DPPC)/ACyDs systems. The lipophilicity of these molecules and the different preparation methods used in this study (thin layer evaporation and nanoprecipitation method) significantly affect the aggregation behaviour in aqueous medium. Except for the shortest medusa-like ACyD4, the other ACyDs formed stable nanoaggregates for at least 45 days. The effect of ACyDs on the thermotropic behaviour of DPPC liposomes was also studied by differential scanning calorimetry analysis, thus elucidating their interaction with liposomes to afford hybrid liposome/ACyDs systems. The medusa-like ACyD4 cannot be used to realize nanosystems because it quickly aggregates or it induces a complete destabilization of the liposomes. At the highest concentration investigated (0.01 molar fraction), both ACyD8 and SC6OH interacted with DPPC liposomes, forming ACyD/DPPC or SC6OH/DPPC hybrid vesicular carriers.
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1,2-Dipalmitoilfosfatidilcolina/química , Ciclodextrinas/química , Portadores de Fármacos/química , Bicamadas Lipídicas/química , Lipossomos/química , Nanoestruturas/química , Varredura Diferencial de Calorimetria , Fenômenos Químicos , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
OBJECTIVE: To compare antidepressant utilization in individuals aged 5-19 years from the Scandinavian countries. METHODS: A population-based drug utilization study using publicly available data of antidepressant use from Denmark, Norway, and Sweden. RESULTS: In the study period from 2007 to 2017, the proportion of antidepressant users increased markedly in Sweden (9.3-18.0/1000) compared to Norway (5.1-7.6/1000) and Denmark (9.3-7.5/1000). In 2017, the cumulated defined daily doses (DDD) of selective serotonin reuptake inhibitors were 5611/1000 inhabitants in Sweden, 2709/1000 in Denmark, and 1848/1000 in Norway. The use of 'other antidepressants' (ATC code N06AX) also increased in Sweden with a higher DDD in 2017 (497/1000) compared to Denmark (225/1000) and Norway (170/1000). The use of tricyclic antidepressants was generally low in 2017 with DDDs ranging between 30-42 per 1000. The proportion of antidepressant users was highest among 15- to 19-year-old individuals. Girls were more likely to receive treatment than boys, and the treated female/male ratios per 1000 were similar in Sweden (2.39), Denmark (2.44), and Norway (2.63). CONCLUSION: Even in highly comparable healthcare systems like the Scandinavian countries', variation in antidepressant use is considerable. Swedish children and adolescents have a markedly higher and still increasing use of antidepressants compared to Danish and Norwegian peers.
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Antidepressivos/uso terapêutico , Uso de Medicamentos/tendências , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Adolescente , Fatores Etários , Antidepressivos Tricíclicos/uso terapêutico , Criança , Pré-Escolar , Dinamarca , Rotulagem de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Masculino , Noruega , Países Escandinavos e Nórdicos , Fatores Sexuais , Suécia , Adulto JovemRESUMO
Refractory inclusions [Ca-Al-rich Inclusions (CAIs) and Amoeboid Olivine Aggregates (AOAs)] in primitive meteorites are the oldest Solar System solids. They formed in the hot inner protoplanetary disk and, as such, provide insights into the earliest disk dynamics and physicochemical processing of the dust and gas that accreted to form the Sun and its planetary system. Using the short-lived 26Al to 26Mg decay system, we show that bulk refractory inclusions in CV (Vigarano-type) and CR (Renazzo-type) carbonaceous chondrites captured at least two distinct 26Al-rich (26Al/27Al ratios of ~5 × 10-5) populations of refractory inclusions characterized by different initial 26Mg/24Mg isotope compositions (µ26Mg*0). Another 26Al-poor CAI records an even larger µ26Mg*0 deficit. This suggests that formation of refractory inclusions was punctuated and recurrent, possibly associated with episodic outbursts from the accreting proto-Sun lasting as short as <8000 yr. Our results support a model in which refractory inclusions formed close to the hot proto-Sun and were subsequently redistributed to the outer disk, beyond the orbit of Jupiter, plausibly via stellar outflows with progressively decreasing transport efficiency. We show that the magnesium isotope signatures in refractory inclusions mirrors the presolar grain record, demonstrating a mutual exclusivity between 26Al enrichments and large nucleosynthetic Mg isotope effects. This suggests that refractory inclusions formed by incomplete thermal processing of presolar dust, thereby inheriting a diluted signature of their isotope systematics. As such, they record snapshots in the progressive sublimation of isotopically anomalous presolar carriers through selective thermal processing of young dust components from the proto-Solar molecular cloud. We infer that 26Al-rich refractory inclusions incorporated 26Al-rich dust which formed <5 Myr prior to our Sun, whereas 26Al-poor inclusions (such as FUN- and PLAC-type CAIs) incorporated >10 Myr old dust.
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BACKGROUND: Anastomotic leakage is a severe complication in gastrointestinal surgery. Different methods have been evaluated for anastomotic reinforcement to prevent anastomotic leakage. The aim of this study was to investigate the effect of a poly-ε-caprolactone (PCL) scaffold incorporated in the staple-line, on the anastomotic strength and histological wound healing, of small intestinal anastomoses in piglets. METHOD: This randomized experimental trial included 17 piglets. In each piglet, three end-to-end anastomoses were performed in the small intestine with a circular stapler, i.e. one control and two interventional anastomoses. On postoperative day 5, the anastomoses were resected and subjected to tension stretch test and histological examination. RESULTS: No anastomotic leakage occurred. In the interventional anastomoses, the mean value for maximal tensile strength was 15.7 N, which was significantly higher than control anastomoses 12.7 N (p = 0.01). No statistically significant differences were found between the two groups in the histopathological parameters. CONCLUSION: To conclude, this study has shown that the incorporation of a PCL scaffold in the staple-line was feasible and significantly increased the maximal tensile strength of small intestine anastomoses in piglets on postoperative day 5. The difference in histological parameters was not significantly distinct.
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Fístula Anastomótica/prevenção & controle , Caproatos/farmacologia , Intestino Delgado/cirurgia , Lactonas/farmacologia , Grampeamento Cirúrgico/métodos , Resistência à Tração/fisiologia , Alicerces Teciduais , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/métodos , Animais , Modelos Animais de Doenças , Feminino , Distribuição Aleatória , Valores de Referência , Estatísticas não Paramétricas , Suínos , Porco MiniaturaRESUMO
STUDY QUESTION: Does female weekly alcohol intake and binge drinking impact the chance of a successful fertility treatment? SUMMARY ANSWER: Low-to-moderate weekly alcohol drinking and binge drinking were not associated with the chance of achieving a clinical pregnancy or a live birth among women and couples undergoing medically assisted reproduction (MAR) treatments. WHAT IS KNOWN ALREADY: Alcohol consumption is common among women of reproductive age, even though health authorities advise women trying to conceive to abstain from drinking. A growing number of couples struggle with infertility, but it is unknown whether low-to-moderate levels of alcohol consumption and alcohol binge drinking impair success in fertility treatment. STUDY DESIGN, SIZE, DURATION: Cohort study with prospectively collected exposure information including 1708 women and potential partners undergoing fertility treatment at the public fertility clinic, Aarhus University Hospital, 1 January 2010 to 31 August 2015. In total, data on 1511 intrauterine insemination (IUI) cycles, 2870 in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles and 1355 frozen embryo transfer cycles. PARTTICIPANTS/MATERIALS, SETTING, METHODS: Exposure to weekly average alcohol intake was assessed from questionnaires completed by participants before the start of treatment. Outcome measures are the achievement of a clinical pregnancy and live birth in consecutive treatment cycles in the Danish national health registries, enabling complete follow-up. A modified Poisson regression with robust standard errors was used to evaluate associations between a weekly average alcohol intake and MAR outcomes, adjusting for female age, body mass index, cigarette smoking, coffee consumption, chronic diseases, level of education, and cycle number. When evaluating the association between binge drinking in the month prior to baseline and MAR outcomes the analyses were further adjusted for average weekly alcohol consumption. MAIN RESULTS AND THE ROLE OF CHANCE: Low-to-moderate average weekly alcohol intake was not statistically significantly associated with the chance of achieving a clinical pregnancy or a live birth following IUI or IVF/ICSI treatment cycles. Compared to women abstaining from alcohol, the adjusted relative risks for achieving a live birth among those reporting 1-2, 3-7, and >7 drinks per week were 1.00 (95% CI 0.66; 1.53), 1.20 (0.76; 1.91), and 1.48 (0.56; 3.93), respectively, among women initiating IUI treatments. Among those initiating IVF/ICSI treatments, the chance for achieving a live birth among those reporting 1-2, 3-7, and >7 drinks per week were 1.00 (0.83; 1.21), 0.95 (0.75; 1.20), and 0.89 (0.53; 1.51), respectively. The chance of achieving a live birth in the first IUI or IVF/ICSI treatment cycle was unrelated to the number of binge drinking episodes in the month preceding baseline. LIMITATIONS, REASONS FOR CAUTION: The risk of non-differential exposure misclassification, confounding, or chance cannot be ruled out. In addition, due to the low number of women reporting an intake of >7 drinks/week, the potential effect of high alcohol consumption should be interpreted with caution. WIDER IMPLICATIONS OF THE FINDINGS: Although it remains unsettled if and how alcohol affects female reproduction, our results indicate that is not necessary to abstain from alcohol when striving for a successful outcome following fertility treatment. STUDY FUNDING/COMPETING INTEREST(S): J.L. is supported by a fully financed Ph.D. scholarship from Aarhus University and has received funds from the A.P. Møller foundation. The funding sources had no involvement in the conduct of the article. Dr Kesmodel reports personal fees from MSD and Ferring Pharmaceuticals outside the submitted work. All other authors have no conflicts of interest to declare and all have completed the ICMJE disclosure form. TRIAL REGISTRATION NUMBER: Not relevant.
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Consumo de Bebidas Alcoólicas/epidemiologia , Coeficiente de Natalidade , Fertilização in vitro/estatística & dados numéricos , Inseminação Artificial/estatística & dados numéricos , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Humanos , GravidezRESUMO
We present a combined experimental and theoretical investigation of the electron dynamics and body-frame angular dependence of valence photo-single ionization of CF4 and subsequent dissociation into CF3+ and F. Ionization from a valence t2 orbital shows overlapping shape resonances close to threshold that couple to the same total symmetry, leading to striking changes in the photoelectron angular distributions when viewed in the body-frame.
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In this Brief Communications Arising Reply, the affiliation for author P. H. Templer was incorrectly listed as 'Department of Ecology & Evolutionary Biology, University of California Irvine, Irvine, California 92697, USA' instead of 'Department of Biology, Boston University, Boston, Massachusetts 02215, USA'. This has been corrected online.
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OBJECTIVES: Nasal endoscopy is a cornerstone in diagnosing sinonasal disease, but different raters might generate different results using the technique. Our study aims to evaluate the agreement between multiple raters to assess the validity of nasal endoscopy. DESIGN/PARTICIPANTS: Three independent and blinded raters evaluated 28 patients (56 nasal cavities) diagnosed with chronic rhinosinusitis according to the European Position Paper on Rhinosinusitis and Nasal Polyps. The ratings were compared using unweighted Fleiss' kappa coefficients (Kf ) for each objective parameter. SETTING: The department of Otorhinolaryngology, Odense University Hospital, Denmark. MAIN OUTCOME MEASURES: The ratings were quantified in a modified Lund-Kennedy endoscopy score and focused on the objective parameters specified in the diagnostic criteria: polyps, oedema and discharge. RESULTS: The raters agreed on the findings concerning polyps and discharge but not regarding oedema with the inter-rater agreement for the different parameters being: polyps Kf =.66 (SE .07, P<.001), oedema Kf =.05 (SE .07, P=.21), discharge Kf =.35 (SE .08, P<.001), oedema exclusively in middle meatus Kf =-.07 (SE .04, P=.8) and discharge exclusively in middle meatus Kf =.16 (SE .07, P=.01). CONCLUSION: Using nasal endoscopy, the evaluation of polyps by multiple raters showed sufficient reliability indicating an acceptable objective evaluation. The evaluation of discharge achieved a fair level of agreement while the assessment of oedema could not achieve a sufficient reliability questioning the inclusion of oedema in the criteria for diagnosing sinonasal disease.
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Endoscopia/métodos , Rinite/diagnóstico , Sinusite/diagnóstico , Adulto , Idoso , Doença Crônica , Dinamarca/epidemiologia , Diagnóstico Diferencial , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Nariz , Curva ROC , Reprodutibilidade dos Testes , Rinite/epidemiologia , Sinusite/epidemiologiaRESUMO
BACKGROUND: Maternal exposures to fever and infections in pregnancy have been linked to subsequent psychiatric morbidity in the child. This study examined whether fever and common infections in pregnancy were associated with psychosis-like experiences (PLEs) in the child. METHODS: A longitudinal study of 46 184 children who participated in the 11-year follow-up of the Danish National Birth Cohort was conducted. Pregnant women were enrolled between 1996 and 2002 and information on fever, genitourinary infections, respiratory tract infection, and influenza-like illness during pregnancy was prospectively collected in two interviews during pregnancy. PLEs were assessed using the seven-item Adolescent Psychotic-Like Symptom Screener in a web-based questionnaire completed by the children themselves at age 11. RESULTS: PLEs were reported among 11% of the children. Multinomial logistic regression models with probability weights to adjust for potential selection bias due to attrition suggested that maternal fever, genitourinary infections and influenza-like illness were associated with a weak to moderate increased risk of subclinical psychosis-like symptoms in the offspring, whereas respiratory tract infections were not. No clear pattern was observed between the strengths of the associations and the timing of exposure, or the type of psychosis-like symptom. CONCLUSIONS: In this study, maternal exposures to fevers and common infections in pregnancy were generally associated with a subtle excess risk of PLEs in the child. A more pronounced association was found for influenza-like illness under an a priori definition, leaving open the possibility that certain kinds of infections may constitute important risk factors.
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Febre/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Efeitos Tardios da Exposição Pré-Natal , Transtornos Psicóticos/epidemiologia , Adulto , Criança , Dinamarca , Feminino , Idade Gestacional , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Relações Mãe-Filho , Gravidez , Estudos Prospectivos , Transtornos Psicóticos/etiologia , Medição de Risco , Fatores de Risco , Inquéritos e Questionários , Adulto JovemRESUMO
It has been demonstrated that extracellular calcium is necessary in fertilisation and embryo development but the mechanism is still not well understood. The present study mainly focussed on the extracellular calcium effector called the calcium-sensing receptor (CASR) and examined its expression in porcine gametes and embryos and its function during fertilisation and early embryo development. By using reverse transcription polymerase chain reaction, CASR was found to be expressed in porcine oocytes, spermatozoa and embryos at different developmental stages. Functionally, medium supplementation with a CASR agonist or an antagonist during in vitro fertilisation (IVF) and in vitro culture (IVC) was tested. During fertilisation, the presence of a CASR agonist increased sperm penetration rate and decreased polyspermy rate leading to an increased normal fertilisation rate. During embryo development, for the IVF embryos, agonist treatment during IVC significantly increased cleavage rate and blastocyst formation rate compared with the control group. Furthermore, parthenogenetically activated embryos showed similar results with lower cleavage and blastocyst formation rates in the antagonist group than in the other groups. It was concluded that CASR, as the effector of extracellular calcium, modulates porcine fertilisation and early embryo development.
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Blastocisto/metabolismo , Sinalização do Cálcio , Fase de Clivagem do Zigoto/metabolismo , Fertilização in vitro , Oócitos/metabolismo , Receptores de Detecção de Cálcio/metabolismo , Espermatozoides/metabolismo , Adamantano/análogos & derivados , Adamantano/farmacologia , Animais , Blastocisto/efeitos dos fármacos , Calcimiméticos/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Fase de Clivagem do Zigoto/efeitos dos fármacos , Técnicas de Cultura Embrionária , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Oócitos/efeitos dos fármacos , Fenetilaminas/farmacologia , Propilaminas/farmacologia , Quinoxalinas/farmacologia , Receptores de Detecção de Cálcio/efeitos dos fármacos , Receptores de Detecção de Cálcio/genética , Espermatozoides/efeitos dos fármacos , Sus scrofaRESUMO
Tracking the secular evolution of 142Nd/144Nd anomalies is important towards understanding the crust-mantle dynamics in the early Earth. Excessive scatter in the published data, however, precludes identifying the fine structure of 142Nd/144Nd evolution as the expected variability is on the order of few parts per million. We report ultra-high precision 142Nd/144Nd data for Eoarchean and Palaeoarchean rocks from the Isua Supracrustal Belt (SW Greenland) that show a well-resolved 142Nd/144Nd temporal variability suggesting progressive convective homogenisation of the Hadean Isua depleted mantle. This temporally decreasing 142Nd/144Nd signal provides a direct measure of early mantle dynamics, defining a stirring timescale of <250 Myr consistent with vigorous convective stirring in the early mantle. The 142Nd/144Nd evolution suggests protracted crustal residence times of ~1000-2000 Myr, inconsistent with modern-style plate tectonics in the Archean. In contrast, a stagnant-lid regime punctuated by episodes of mantle overturns accounts for the long life-time estimated here for the Hadean proto-crust.
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Cognitive dysfunction is common in depression during both acute episodes and remission. Vortioxetine is a novel multimodal antidepressant that has improved cognitive function including executive function in depressed patients in randomised placebo-controlled clinical trials. However, it is unclear whether vortioxetine is able to target directly the neural circuitry implicated in the cognitive deficits in depression. Remitted depressed (n=48) and healthy volunteers (n=48) were randomised to receive 14 days treatment with 20 mg vortioxetine or placebo in a double-blind design. The effects of treatment on functional magnetic resonance imaging responses during an N-back working memory task were assessed at baseline and at the end of treatment. Neuropsychological measures of executive function, speed and information processing, attention and learning and memory were examined with the Trail Making Test (TMT), Rey Auditory Learning Test and Digit Symbol Substitution Test before and after treatment; subjective cognitive function was assessed using the Perceived Deficits Questionnaire (PDQ). Compared with placebo, vortioxetine reduced activation in the right dorsolateral prefrontal cortex and left hippocampus during the N-back task compared with placebo. Vortioxetine also increased TMT-A performance and self-reported cognitive function on the PDQ. These effects were seen across both subject groups. Vortioxetine modulates neural responses across a circuit subserving working memory in a direction opposite to the changes described in depression, when performance is maintained. This study provides evidence that vortioxetine has direct effects on the neural circuitry supporting cognitive function that can be dissociated from its effects on the mood symptoms of depression.