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Self-driving laboratories (SDLs) promise an accelerated application of the scientific method. Through the automation of experimental workflows, along with autonomous experimental planning, SDLs hold the potential to greatly accelerate research in chemistry and materials discovery. This review provides an in-depth analysis of the state-of-the-art in SDL technology, its applications across various scientific disciplines, and the potential implications for research and industry. This review additionally provides an overview of the enabling technologies for SDLs, including their hardware, software, and integration with laboratory infrastructure. Most importantly, this review explores the diverse range of scientific domains where SDLs have made significant contributions, from drug discovery and materials science to genomics and chemistry. We provide a comprehensive review of existing real-world examples of SDLs, their different levels of automation, and the challenges and limitations associated with each domain.
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PURPOSE OF REVIEW: Stress hyperglycaemia occur often in critically injured patients. To gain new consideration about it, this review compile current as well as known immunological and biochemical findings about causes and emergence. RECENT FINDINGS: Glucose is the preferred energy substrate for fending immune cells, reparative tissue and the cardiovascular system following trauma. To fulfil these energy needs, the liver is metabolically reprogrammed to rebuild glucose from lactate and glucogenic amino acids (hepatic insulin resistance) at the expenses of muscles mass and - to a less extent - fat tissue (proteolysis, lipolysis, peripheral insulin resistance). This inevitably leads to stress hyperglycaemia, which is evolutionary preserved and seems to be an essential and beneficial survival response. It is initiated by damage-associated molecular patterns (DAMPs) and pathogen-associated molecular patterns (PAMPs), intensified by immune cells itself and mainly ruled by tumour necrosis factor (TNF)α and catecholamines with lactate and hypoxia inducible factor (HIF)-1α as intracellular signals and lactate as an energy shuttle. Important biochemical mechanisms involved in this response are the Warburg effect as an efficient metabolic shortcut and the extended Cori cycle. SUMMARY: Stress hyperglycaemia is beneficial in an acute life-threatening situation, but further research is necessary, to prevent trauma patients from the detrimental effects of persisting hyperglycaemia.
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Hiperglicemia , Resistência à Insulina , Humanos , Glucose , Insulina , LactatosRESUMO
The olefin metathesis activity of silica-supported molybdenum oxides depends strongly on metal loading and preparation conditions, indicating that the nature and/or amounts of the active sites vary across compositionally similar catalysts. This is illustrated by comparing Mo-based (pre)catalysts prepared by impregnation (2.5-15.6 wt % Mo) and a model material (2.3 wt % Mo) synthesized via surface organometallic chemistry (SOMC). Analyses of FTIR, UV-vis, and Mo K-edge X-ray absorption spectra show that these (pre)catalysts are composed predominantly of similar isolated Mo dioxo sites. However, they exhibit different reaction properties in both liquid and gas-phase olefin metathesis with the SOMC-derived catalyst outperforming a classical catalyst of a similar Mo loading by ×1.5-2.0. Notably, solid-state 95Mo NMR analyses leveraging state-of-the-art high-field (28.2 T) measurement conditions resolve four distinct surface Mo dioxo sites with distributions that depend on the (pre)catalyst preparation methods. The intensity of a specific deshielded 95Mo NMR signal, which is most prominent in the SOMC-derived catalyst, is linked to reducibility and catalytic activity. First-principles calculations show that 95Mo NMR parameters directly manifest the local strain and coordination environment: acute (SiO-Mo(O)2-OSi) angles and low coordination numbers at Mo lead to highly deshielded 95Mo chemical shifts and small quadrupolar coupling constants, respectively. Natural chemical shift analyses relate the 95Mo NMR signature of strained species to low LUMO energies, which is consistent with their high reducibility and corresponding reactivity. The 95Mo chemical shifts of supported Mo dioxo sites are thus linked to their specific electronic structures, providing a powerful descriptor for their propensity toward reduction and formation of active sites.
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The pharmacokinetics and antifungal activity of the echinocandins anidulafungin (AFG), micafungin (MFG), and caspofungin (CAS) were assessed in ascites fluid and plasma of critically ill adults treated for suspected or proven invasive candidiasis. Ascites fluid was obtained from ascites drains or during paracentesis. The antifungal activity of the echinocandins in ascites fluid was assessed by incubation of Candida albicans and Candida glabrata at concentrations of 0.03 to 16.00 µg/ml. In addition, ascites fluid samples obtained from our study patients were inoculated with the same isolates and evaluated for fungal growth. These patient samples had to be spiked with echinocandins to restore the original concentrations because echinocandins had been lost during sterile filtration. In ascites fluid specimens of 29 patients, echinocandin concentrations were below the simultaneous plasma levels. Serial sampling in 20 patients revealed a slower rise and decline of echinocandin concentrations in ascites fluid than in plasma. Proliferation of C. albicans in ascites fluid was slower than in culture medium and growth of C. glabrata was lacking, even in the absence of antifungals. In CAS-spiked ascites fluid samples, fungal CFU counts moderately declined, whereas spiking with AFG or MFG had no relevant effect. In ascites fluid of our study patients, echinocandin concentrations achieved by therapeutic doses did not result in a consistent eradication of C. albicans or C. glabrata. Thus, therapeutic doses of AFG, MFG, or CAS may result in ascites fluid concentrations preventing relevant proliferation of C. albicans and C. glabrata, but do not warrant reliable eradication.
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Antifúngicos , Equinocandinas , Adulto , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Ascite/tratamento farmacológico , Estado Terminal , Humanos , Lipopeptídeos , Testes de Sensibilidade MicrobianaRESUMO
OBJECTIVES: Non-operative management (NOM) is increasingly utilised in blunt abdominal trauma. The 1994 American Association of Surgery of Trauma grading (1994-AAST) is applied for clinical decision-making in many institutions. Recently, classifications incorporating contrast extravasation such as the CT severity index (CTSI) and 2018 update of the liver and spleen AAST were proposed to predict outcome and guide treatment, but validation is pending. METHODS: CT images of patients admitted 2000-2016 with blunt splenic and hepatic injury were systematically re-evaluated for 1994/2018-AAST and CTSI grading. Diagnostic accuracy, diagnostic odds ratio (DOR), and positive and negative predictive values were calculated for prediction of in-hospital mortality. Correlation with treatment strategy was assessed by Cramer V statistics. RESULTS: Seven hundred and three patients were analysed, 271 with splenic, 352 with hepatic and 80 with hepatosplenic injury. Primary NOM was applied in 83% of patients; mortality was 4.8%. Comparing prediction of mortality in mild and severe splenic injuries, the CTSI (3.1% vs. 10.3%; diagnostic accuracy = 75.4%; DOR = 3.66; p = 0.006) and 1994-AAST (3.3% vs. 10.5%; diagnostic accuracy = 77.9%; DOR = 3.45; p = 0.010) were more accurate compared with the 2018-AAST (3.4% vs. 8%; diagnostic accuracy = 68.2%; DOR = 2.50; p = 0.059). In hepatic injuries, the CTSI was superior to both AAST classifications in terms of diagnostic accuracy (88.7% vs. 77.1% and 77.3%, respectively). CTSI and 2018-AAST correlated better with the need for surgery in severe vs. mild hepatic (Cramer V = 0.464 and 0.498) and splenic injuries (Cramer V = 0.273 and 0.293) compared with 1994-AAST (Cramer V = 0.389 and 0.255; all p < 0.001). CONCLUSIONS: The 2018-AAST and CTSI are superior to the 1994-AAST in correlation with operative treatment in splenic and hepatic trauma. The CTSI outperforms the 2018-AAST in mortality prediction. KEY POINTS: ⢠Non-operative management of blunt abdominal trauma is increasingly applied and correct patient stratification is crucial. ⢠CT-based scoring systems are used to assess injury severity and guide clinical decision-making, whereby the 1994 version of the American Association of Surgery of Trauma Organ Injury Scale (AAST-OIS) is currently most commonly utilised. ⢠Including contrast media extravasation in CT-based grading improves management and outcome prediction. While the 2018-AAST classification and the CT-severity-index (CTSI) better correlate with need for surgery compared to the 1994-AAST, the CTSI is superior in outcome-prediction to the 2018-AAST.
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Escala de Gravidade do Ferimento , Fígado/diagnóstico por imagem , Fígado/lesões , Baço/diagnóstico por imagem , Baço/lesões , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/mortalidade , Traumatismos Abdominais , Adolescente , Adulto , Biometria , Sistemas de Apoio a Decisões Clínicas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Estados Unidos , Adulto JovemRESUMO
PURPOSE: To assess the impact of serum androgen levels and androgen receptor CAG polymorphism on sexual function in 45 healthy midlife women living in a heterosexual relationship. METHODS: Cross-sectional study [Cantonal Ethics Committee Bern (Ref.-Nr. KEK-BE: 087/13)]. MAIN OUTCOME MEASURES: Association between androgen serum levels, androgen receptor CAG polymorphism and sexual function was assessed by the FSFI-d questionnaire. RESULTS: In our cohort of healthy, midlife, well-educated, middle-class, mostly postmenopausal women living in a heterosexual satisfying partnership, sexual function was perceived to remain stable or to decline during menopausal transition with sexual desire scoring lowest (FSFI-d 3.3 ± 0.9). Androgen serum levels did not correlate with sexual function. Mean CAG repeat number was 21.6 ± 1.9. There was a highly inverse though non-significant correlation between female sexual function and AR CAG repeat polymorphism with specifically higher numbers of CAG repeats being significantly positively correlated to more frequent or more severe pain during or after sexual intercourse. CONCLUSION: The AR polymorphism is a non-negligible factor in female sexual function. Future studies on female sexual (dys)function should incorporate its assessment.
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Polimorfismo Genético , Receptores Androgênicos/genética , Comportamento Sexual/fisiologia , Repetições de Trinucleotídeos , Estudos Transversais , Feminino , Humanos , Libido/fisiologia , Masculino , Pessoa de Meia-Idade , Testosterona/sangueRESUMO
BACKGROUND: Deranged glucose metabolism after moderate to severe trauma with either high or low concentrations of blood glucose is associated with poorer outcome. Data on prehospital blood glucose concentrations and trauma are scarce. OBJECTIVES: The primary aim was to describe the relationship between traumatic shock and prehospital blood glucose concentrations. The secondary aim was to determine the additional predictive value of prehospital blood glucose concentration for traumatic shock when compared with vital parameters alone. DESIGN: Retrospective analysis of the predefined, observational database of a nationwide Helicopter Emergency Medical Service (34 bases). SETTING: Emergency trauma patients treated by Helicopter Emergency Medical Service between 2005 and 2013 were investigated. PATIENTS: All adult trauma patients (≥18 years) with recorded blood glucose concentrations were enrolled. OUTCOMES: Primary outcome: upper and lower thresholds of blood glucose concentration more commonly associated with traumatic shock. Secondary outcome: additional predictive value of prehospital blood glucose concentrations when compared with vital parameters alone. RESULTS: Of 51â936 trauma patients, 20â177 were included. In total, 220 (1.1%) patients died on scene. Hypoglycaemia (blood glucose concentration 2.8âmmolâl or less) was observed in 132 (0.7%) patients, hyperglycaemia (blood glucose concentration exceeding 15âmmolâl) was observed in 265 patients (1.3%). Blood glucose concentrations more than 10âmmolâl (nâ=â1308 (6.5%)) and 2.8âmmolâl or less were more common in patients with traumatic shock (Pâ<â0.0001). The Youden index for traumatic shock ((sensitivityâ+âspecificity)â-â1) was highest when blood glucose concentration was 3.35âmmolâl (Pâ<â0.001) for patients with low blood glucose concentrations and 7.75âmmol l (Pâ<â0.001) for those with high blood glucose concentrations. In logistic regression analysis of patients with spontaneous circulation on scene, prehospital blood glucose concentrations (together with common vital parameters: Glasgow Coma Scale, heart rate, blood pressure, breathing frequency) significantly improved the prediction of traumatic shock in comparison with prediction by common vital parameters alone (Pâ<â0.0001). CONCLUSION: In adult trauma patients, low and high blood glucose concentrations were more common in patients with traumatic shock. Prehospital blood glucose concentration measurements in addition to common vital parameters may help identify patients at risk of traumatic shock.
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Glicemia/metabolismo , Serviços Médicos de Emergência , Choque Traumático/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Resgate Aéreo , Biomarcadores/sangue , Bases de Dados Factuais , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Choque Traumático/diagnóstico , Choque Traumático/mortalidade , Choque Traumático/terapia , Índices de Gravidade do Trauma , Adulto JovemRESUMO
More and more social interactions happen online. On online social networks such as Instagram, millions of users share, like, and comment on photos and videos every day, interacting with other users world wide, at large scale and at a high rate. These networks do not only introduce new user experiences, but they also enable new insights into human behavior. Here, we use these new possibilities to study homophilic behavior-the tendency of individuals to bond with people similar to themselves. While homophilic behavior has been observed in many contexts, little is known about gender-specific differences and the extent of homophilic behavior of female and male users in online social networks. Based on a unique and extensive data set, covering over 800,000 (directed) Instagram interactions and a time span of three years, we shed light on differences between genders and uncover an intriguing asymmetry of homophily. In particular, we show that female users exhibit homophily to a larger extent than male users. The magnitude of this asymmetry depends on the type of interaction, as differences are more pronounced for 'comment'-interactions than for 'like'-interactions. Given these empirical observations, we further study the implications of such gender differences on the spread of information in social networks in a basic model. We find that on average, a piece of information that originates from a female group reaches significantly more female users than male users.
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Comportamento Social , Mídias Sociais , Humanos , Masculino , Feminino , Rede Social , Interação Social , Inquéritos e QuestionáriosRESUMO
Whole-body lifting strategies could be derived from conventional video recordings using the Stoop-Squat-Index, which quantifies the ratio between trunk forward lean and lower extremity joint flexion from 0 (full squat) to 100 (full stoop). The purpose of this study was to compare Stoop-Squat-Indices derived from conventional video recordings to those from a three-dimensional marker-based motion capture system and to evaluate interrater and intrarater reliability of the video-based approach. Thirty healthy participants lifted a 5-kg box under different conditions (freestyle, squat, stoop). Kinematic data were recorded using a Vicon motion capture system (serving as reference standard) and an iPad camera. Stoop-Squat-Indices over the entire lifting cycle were derived separately from both approaches. Agreement was assessed using mean differences (video minus motion capture) and limits of agreement. Reliability was investigated by calculating intraclass correlation coefficients (ICC) and minimal detectable changes (MDC) over the course of the lifting cycle. Systematic errors were identified with Statistical Parametric Mapping-based T-tests. Systematic errors between the video-based and the motion capture-based approach were observed among all conditions. Mean differences in Stoop-Squat-Indices over the lifting cycle ranged from -6.9 to 3.2 (freestyle), from -1.8 to 5.3 (squat) and from -2.8 to -1.1 (stoop). Limits of agreement were lower when the box was close to the floor, and higher towards upright standing. Reliability of the video-based approach was excellent for most of the lifting cycle, with ICC above 0.995 and MDC below 3.5. These findings support using a video-based assessment of Stoop-Squat-Indices to quantify whole-body lifting strategy in field.
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Remoção , Captura de Movimento , Humanos , Reprodutibilidade dos Testes , Articulações , Gravação em Vídeo , Fenômenos BiomecânicosRESUMO
Musculoskeletal (MSK) models offer great potential for predicting the muscle forces required to inform more detailed simulations of vertebral endplate loading in adolescent idiopathic scoliosis (AIS). In this work, simulations based on static optimization were compared with in vivo measurements in two AIS patients to determine whether computational approaches alone are sufficient for accurate prediction of paraspinal muscle activity during functional activities. We used biplanar radiographs and marker-based motion capture, ground reaction force, and electromyography (EMG) data from two patients with mild and moderate thoracolumbar AIS (Cobb angles: 21° and 45°, respectively) during standing while holding two weights in front (reference position), walking, running, and object lifting. Using a fully automated approach, 3D spinal shape was extracted from the radiographs. Geometrically personalized OpenSim-based MSK models were created by deforming the spine of pre-scaled full-body models of children/adolescents. Simulations were performed using an experimentally controlled backward approach. Differences between model predictions and EMG measurements of paraspinal muscle activity (both expressed as a percentage of the reference position values) at three different locations around the scoliotic main curve were quantified by root mean square error (RMSE) and cross-correlation (XCorr). Predicted and measured muscle activity correlated best for mild AIS during object lifting (XCorr's ≥ 0.97), with relatively low RMSE values. For moderate AIS as well as the walking and running activities, agreement was lower, with XCorr reaching values of 0.51 and comparably high RMSE values. This study demonstrates that static optimization alone seems not appropriate for predicting muscle activity in AIS patients, particularly in those with more than mild deformations as well as when performing upright activities such as walking and running.
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Cifose , Escoliose , Criança , Humanos , Adolescente , Escoliose/diagnóstico por imagem , Eletromiografia , Músculos Paraespinais/diagnóstico por imagem , Coluna VertebralRESUMO
Prospective studies addressing the clinical value of broad-range PCR using the internal transcribed spacer region (ITS) for diagnosis of microscopy-negative fungal infections in nonselected patient populations are lacking. We first assessed the diagnostic performance of ITS rRNA gene PCR compared with that of routine microscopic immunofluorescence examination. Second, we addressed prospectively the impact and clinical value of broad-range PCR for the diagnosis of infections using samples that tested negative by routine microscopy; the corresponding patients' data were evaluated by detailed medical record reviews. Results from 371 specimens showed a high concordance of >80% for broad-range PCR and routine conventional methods, indicating that the diagnostic performance of PCR for fungal infections is comparable to that of microscopy, which is currently considered part of the "gold standard." In this prospective study, 206 specimens with a negative result on routine microscopy were analyzed with PCR, and patients' clinical data were reviewed according to the criteria of the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group. We found that broad-range PCR showed a sensitivity, specificity, positive predictive value, and negative predictive value of 57.1%, 97.0%, 80%, and 91.7%, respectively, for microscopy-negative fungal infections. This study defines a possible helpful role of broad-range PCR for diagnosis of microscopy-negative fungal infections in conjunction with other tests.
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Fungos/isolamento & purificação , Técnicas Microbiológicas/métodos , Micologia/métodos , Micoses/diagnóstico , Micoses/microbiologia , Reação em Cadeia da Polimerase/métodos , DNA Fúngico/genética , DNA Fúngico/isolamento & purificação , DNA Espaçador Ribossômico/genética , DNA Espaçador Ribossômico/isolamento & purificação , Fungos/classificação , Fungos/genética , Humanos , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e EspecificidadeRESUMO
An important prerequisite to carry out daily activities is the sit-to-stand movement. However, in obese people, this movement is characterized by altered biomechanics, which might lead to daily life activity impairments. The aim of this study was to investigate whether there are differences in kinetic and kinematic variables between three different BMI categories when performing a specific sit-to-stand test. Thirty-six adult women (BMI = 17-45 kg/m²) performed the sit-to stand test five times consecutively and as quickly as possible. Analyses of variance were used to determine differences between three BMI groups (normal or overweight: BMI < 30 kg/m²; obese: 30 ≤ BMI < 35; severely obese: BMI ≥ 35). Peak and mean vertical sacrum velocity indicated a decrease in severely obese subjects. Obese and severely obese individuals did not show higher fatigue over the five consecutive movements. Peak force and rate of force development decreased in normal or overweight subjects. The ability to successfully complete the test decreased with a higher BMI, probably due to a reduced ability to rapidly generate a high force.
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Índice de Massa Corporal , Movimento , Fadiga Muscular , Obesidade/fisiopatologia , Esforço Físico , Postura , Análise e Desempenho de Tarefas , Atividades Cotidianas , Adulto , Idoso , Envelhecimento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Equilíbrio Postural , Estresse MecânicoRESUMO
Low back pain (LBP) can result in increased direct medical and non-medical costs to patients, employers, and health care providers. This systematic review aimed to provide a better understanding of the biomechanical factors associated with chronic non-specific LBP in adults. SCOPUS, ScienceDirect, MEDLINE, and Web of Science databases were searched. In total, 26 studies were included and significant differences were noted between healthy controls and LBP patients in various motion. Biomechanical factors among adults with non-specific LBP were altered and differed as compared to healthy controls in various motion might be to compensate the pain during those motions. This review highlighted the biomechanical differences across those with non-specific LBP and healthy adults. Both groups showed a similar level of pain during functional tasks but LBP patients suffered from a moderate level of disability. Future studies should not rely on questionnaire-based pain scale only. The biomechanical factors summarized in this review can be used to diagnose non-specific LBP accurately, and as modifiable targets for exercise-based intervention.
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Dor Lombar , Adulto , Humanos , Medição da Dor , Fenômenos Biomecânicos , Amplitude de Movimento ArticularRESUMO
Candida auris is a novel and emerging pathogenic yeast which represents a serious global health threat. Since its first description in Japan 2009, it has been associated with large hospital outbreaks all over the world and is often resistant to more than one antifungal drug class. To date, five C. auris isolates have been detected in Austria. Morphological characterization and antifungal susceptibility profiles against echinocandins, azoles, polyenes and pyrimidines, as well as the new antifungals ibrexafungerp and manogepix, were determined. In order to assess pathogenicity of these isolates, an infection model in Galleria mellonella was performed and whole genome sequencing (WGS) analysis was conducted to determine the phylogeographic origin. We could characterize four isolates as South Asian clade I and one isolate as African clade III. All of them had elevated minimal inhibitory concentrations to at least two different antifungal classes. The new antifungal manogepix showed high in vitro efficacy against all five C. auris isolates. One isolate, belonging to the African clade III, showed an aggregating phenotype, while the other isolates belonging to South Asian clade I were non-aggregating. In the Galleria mellonella infection model, the isolate belonging to African clade III exhibited the lowest in vivo pathogenicity. As the occurrence of C. auris increases globally, it is important to raise awareness to prevent transmission and hospital outbreaks.
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PURPOSE: To further analyse causes and effects of ICU-acquired hypernatremia. METHODS: This retrospective, single-centre study, analysed 994 patients regarding ICU-acquired hypernatremia. Non-hypernatremic patients (n = 617) were compared to early-hypernatremic (only before ICU-day 4; n = 87), prolonged-hypernatremic (before and after ICU-day 4; n = 169) and late-hypernatremic patients (only after ICU-day 4; n = 121). Trends in glomerular filtration rate (eGFR), urea-to-creatinine ratio (UCR), fraction of urea in total urine osmolality and urine sodium were compared. Risk factors for i) the development of hypernatremia and ii) mortality were determined. RESULTS: Thirty-eight percent (n = 377) developed ICU-acquired hypernatremia. Specifically in the prolonged- and late-group, decreased eGFRs and urine sodium but increased UCR and fractions of urea in urine osmolality were present. Decreased eGFR was a risk factor for the development of hypernatremia in all groups; disease severity and increased catabolism particularly in the prolonged- and late-hypernatremic group. Increased age, SAPS-III and signs of catabolism but not the development of hypernatremia itself was identified as significant risk factor for mortality. CONCLUSIONS: Late- and prolonged-hypernatremia is highly related to an increased protein metabolism. Besides excessive catabolism, initial disease severity and a decrease in renal function must be considered when confronted with ICU-acquired hypernatremia.
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Hipernatremia , Humanos , Hipernatremia/etiologia , Estudos Retrospectivos , Unidades de Terapia Intensiva , Ureia , SódioRESUMO
Electrodynamic ion funnel interfaces for electrospray ionization (ESI) have shown to enhance the sensitivity of measurements by more than 2 orders of magnitude in the intermediate pressure region of the instrument (1-30 Torr). In this study, we use an ion funnel at ambient pressure to enhance the sensitivity of extractive electrospray ionization (EESI) by spraying directly into the ion funnel. EESI is a powerful ionization technique that is capable of handling complex matrixes that may contain dozens of compounds. Our results using atenolol, salbutamol, and cocaine as test compounds show that we can improve the limit of detection for these compounds by more than 3 orders of magnitude compared to standard EESI experiments.
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We report on three-body recombination of a single trapped Rb(+) ion and two neutral Rb atoms in an ultracold atom cloud. We observe that the corresponding rate coefficient K(3) depends on collision energy and is about a factor of 1000 larger than for three colliding neutral Rb atoms. In the three-body recombination process large energies up to several 0.1 eV are released leading to an ejection of the ion from the atom cloud. It is sympathetically recooled back into the cloud via elastic binary collisions with cold atoms. Further, we find that the final ionic product of the three-body processes is again an atomic Rb(+) ion suggesting that the ion merely acts as a catalyzer, possibly in the formation of deeply bound Rb(2) molecules.
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BACKGROUND: Heterozygous mutations in the glucocerebrosidase gene lead to an increased risk for and to more severe alpha-synuclein-associated pathology in Parkinson's disease. As both glucocerebrosidase and alpha-synuclein interact with fatty acids, we hypothesized that cerebrospinal fluid fatty acid levels are altered in these Parkinson's disease patients. METHODS: Cerebrospinal fluid levels of 13 fatty acids in 8 Parkinson's disease patients with a heterozygous glucocerebrosidase mutation were compared with those of 41 idiopathic Parkinson's disease patients and 30 controls using gas chromatography. RESULTS: Parkinson's disease patients with a heterozygous glucocerebrosidase mutation had lower levels of palmitoleic (P ≤ .007), oleic (P ≤ .016), linoleic (P ≤ .005), arachidonic (P ≤ .003), eicosapentaenoic (P ≤ .003) and decosahexaenoic (P ≤ .03) acids and lower levels of total fatty acids (P < .005) compared with both idiopathic Parkinson's disease patients and control subjects. CONCLUSIONS: These results suggest that abnormalities of fatty acid metabolism are specifically involved in the pathogenesis of Parkinson's disease associated with a heterozygous glucocerebrosidase mutation.
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Ácidos Graxos/líquido cefalorraquidiano , Glucosilceramidase/genética , Mutação/genética , Doença de Parkinson/líquido cefalorraquidiano , Doença de Parkinson/genética , Idoso , Idoso de 80 Anos ou mais , Feminino , Heterozigoto , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Plasma air purifying systems present an interesting alternative to filters for purifying air. In this study, molecular processes in a commercially available ac driven plasma air purifier were studied in detail. This air purifier is supposed to reduce all air contaminants to small nontoxic molecules (e.g., H(2)O and CO(2)). However, degradation mechanisms are not yet fully understood. In this study, we investigated the exhaust of the plasma air purifier to determine which degradation products are formed. An interface was designed and constructed to allow the direct coupling of the plasma air purifier's exhaust to a mass spectrometer. The compounds studied, primary and secondary amines, were introduced at a concentration of 1 ppmV. Contrary to our expectations, polymerization instead of degradation was observed. The higher the ac voltage applied (max. 9.0 kV) to the plasma air purifier, the higher the mass of the oligomer distribution. Side chain oxidation products as well as oligomers could be observed for all compounds tested. Starting with amines of low mass (m/z < 200), compounds of molecular masses above 1000 Da were observed in the plasma air purifier. Detailed analysis of the observed mass spectra as well as experiments with deuterated dibutylamine helped to unravel the mechanism taking place in the plasma air purifier. Nitrate anions generated in the plasma air purifier (presumably from N(2)) are proposed to form ionic clusters with protonated amines.