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1.
Affect Sci ; 2(1): 48-57, 2021 Mar.
Article in English | MEDLINE | ID: mdl-36042918

ABSTRACT

The aim of this study was to examine the effects of a 24-week aerobic exercise training program on daily psychological processes and occurrence of stressors in a group of previously physically underactive family caregivers of patients with dementia. As part of the Fitness, Aging, and STress (FAST) randomized controlled trial, 68 participants (F = 55; M = 13) were randomized to either a staff-supported, 24-week aerobic training (N = 34) program or waitlist control (N = 34) group. Approximately 2 weeks prior to randomization, ecological momentary assessments were completed 6 times per day for 7 days and again in the 24th week of the trial to assess exposure to levels of momentary positive affect, negative affect, rumination, control, and the occurrence of stressors throughout the day. These secondary analyses with data from 56 of the participants revealed that the intervention group showed a significantly larger increase in daily positive affect and perceptions of control compared to control participants over the course of the intervention. A treatment effect was also found for negative affect and rumination, whereby both decreased to a greater extent in the intervention group when compared with participants in the control condition. The 24-week aerobic training program had significant impacts on daily psychological processes in family caregivers, deepening our understanding of the robust effects of exercise on mental health.

2.
Nano Lett ; 20(12): 8689-8695, 2020 Dec 09.
Article in English | MEDLINE | ID: mdl-33175553

ABSTRACT

Single-photon emitting point defects in semiconductors have emerged as strong candidates for future quantum technology devices. In the present work, we exploit crystalline particles to investigate relevant defect localizations, emission shifting, and waveguiding. Specifically, emission from 6H-SiC micro- and nanoparticles ranging from 100 nm to 5 µm in size is collected using cathodoluminescence (CL), and we monitor signals attributed to the Si vacancy (VSi) as a function of its location. Clear shifts in the emission wavelength are found for emitters localized in the particle center and at the edges. By comparing spatial CL maps with strain analysis carried out in transmission electron microscopy, we attribute the emission shifts to compressive strain of 2-3% along the particle a-direction. Thus, embedding VSi qubit defects within SiC nanoparticles offers an interesting and versatile opportunity to tune single-photon emission energies while simultaneously ensuring ease of addressability via a self-assembled SiC nanoparticle matrix.

3.
J Phys Condens Matter ; 32(50)2020 Sep 23.
Article in English | MEDLINE | ID: mdl-32756022

ABSTRACT

The evolution of electrical resistance as function of defect concentration is examined for the unipolarn-conducting oxides CdO,ß-Ga2O3, In2O3, SnO2and ZnO in order to explore the predictions of the amphoteric defect model. Intrinsic defects are introduced by ion irradiation at cryogenic temperatures, and the resistance is measured in-situ by current-voltage sweeps as a function of irradiation dose. Temperature dependent Hall effect measurements are performed to determine the carrier concentration and mobility of the samples before and after irradiation. After the ultimate irradiation step, the Ga2O3and SnO2samples have both turned highly resistive. In contrast, the In2O3and ZnO samples are ultimately found to be less resistive than prior to irradiation, however, they both show an increased resistance at intermediate doses. Based on thermodynamic defect charge state transitions computed by hybrid density functional theory, a model expanding on the current amphoteric defect model is proposed.

4.
Nanoscale Adv ; 2(2): 724-733, 2020 Feb 18.
Article in English | MEDLINE | ID: mdl-36133232

ABSTRACT

The optical properties of single ion tracks have been studied in ZnO implanted with Ge by combining depth-resolved hyperspectral cathodoluminescence (CL) and photoluminescence (PL) spectroscopy techniques. The results indicate that ZnO is susceptible to implantation doses as low as 108 to 109 cm-2. We demonstrate that the intensity ratio of ionized and neutral donor bound exciton emissions [D+X/D0X] can be used as a tracer for a local band bending both at the surface as well as in the crystal bulk along the ion tracks. The hyperspectral CL imaging performed at 80 K with 50 nm resolution over the regions with single ion tracks permitted direct assessment of the minority carrier diffusion length. The radii of distortion and space charge surrounding single ion tracks were estimated from the 2D distributions of defect-related green emission (GE) and excitonic D+X emission, both normalized with regard to neutral D0X emission, i.e., from the [GE/D0X] and [D+X/D0X] ratio maps. Our results indicate that single ion tracks in ZnO can be resolved up to ion doses of the order of 5 × 109 cm-2, in which defect aggregation along the extended defects obstructs signatures of individual tracks.

5.
Nanotechnology ; 29(31): 318002, 2018 Aug 03.
Article in English | MEDLINE | ID: mdl-29749345

ABSTRACT

We respond to the comment by Thomas Walther and reaffirm the findings of our original article.

6.
Clin Nurs Res ; 27(5): 579-596, 2018 06.
Article in English | MEDLINE | ID: mdl-28114792

ABSTRACT

The aim of this study was to determine the extent to which poor physical functioning, low participation in physical activity, and muscle atrophy observed among patients on hemodialysis are evident in the earlier stages of chronic kidney disease (CKD). We enrolled adults in three groups: no CKD, Stages 3 to 4 CKD, and hemodialysis. Outcomes measured were physical activity, muscle size, thigh muscle strength, physical performance, and self-reported physical function. Patients with CKD had muscle area intermediate between the no CKD and hemodialysis groups, but they had low levels of physical activity that were similar to the hemodialysis group. Physical activity and muscle size were significantly associated with all outcomes. Kidney function was not significantly associated with muscle strength or physical performance after adjustment for physical activity and muscle size. In conclusion, interventions aimed to increase muscle mass and energy expenditure might have an impact on improving physical function of CKD patients.


Subject(s)
Exercise/physiology , Kidney/physiology , Muscle Strength/physiology , Renal Insufficiency, Chronic/physiopathology , Accelerometry , Female , Humans , Male , Middle Aged , Quality of Life , Self Report
7.
Nat Commun ; 8(1): 1064, 2017 10 20.
Article in English | MEDLINE | ID: mdl-29057953

ABSTRACT

Lytic polysaccharide monooxygenases (LPMOs) are industrially important copper-dependent enzymes that oxidatively cleave polysaccharides. Here we present a functional and structural characterization of two closely related AA9-family LPMOs from Lentinus similis (LsAA9A) and Collariella virescens (CvAA9A). LsAA9A and CvAA9A cleave a range of polysaccharides, including cellulose, xyloglucan, mixed-linkage glucan and glucomannan. LsAA9A additionally cleaves isolated xylan substrates. The structures of CvAA9A and of LsAA9A bound to cellulosic and non-cellulosic oligosaccharides provide insight into the molecular determinants of their specificity. Spectroscopic measurements reveal differences in copper co-ordination upon the binding of xylan and glucans. LsAA9A activity is less sensitive to the reducing agent potential when cleaving xylan, suggesting that distinct catalytic mechanisms exist for xylan and glucan cleavage. Overall, these data show that AA9 LPMOs can display different apparent substrate specificities dependent upon both productive protein-carbohydrate interactions across a binding surface and also electronic considerations at the copper active site.


Subject(s)
Mixed Function Oxygenases/chemistry , Mixed Function Oxygenases/metabolism , Polysaccharides/metabolism , Catalytic Domain , Copper/chemistry , Electron Spin Resonance Spectroscopy , Fungal Proteins/chemistry , Fungal Proteins/metabolism , Models, Molecular , Polyporaceae/enzymology , Polysaccharides/chemistry , Sordariales/enzymology , Substrate Specificity
8.
Carbohydr Res ; 448: 182-186, 2017 Aug 07.
Article in English | MEDLINE | ID: mdl-28335986

ABSTRACT

Light-driven activation of lytic polysaccharide monooxygenases (LPMOs) has been attributed to the transfer of high redox potential electrons from excited photopigments to the enzyme. However, due to the formation of reactive oxygen species (ROS) in such a system, not only electrons from the pigments but also ROS could be part of the enzyme mechanism. This work investigates the role of ROS in the oxidation of phosphoric acid swollen cellulose (PASC) by a light-driven LPMO system. Our results clearly show that the addition of superoxide dismutase or catalase to remove ROS did not attenuate the capacity of the light-driven LPMO system to oxidize PASC, as measured by formation of oxidized oligosaccharides. We conclude that ROS are not part of the light-driven LPMO activation; hence, transfer of high redox potential electrons from the excited photopigment to the LPMO remains the most likely mechanism under the conditions tested in this study.


Subject(s)
Cellulose/chemistry , Cellulose/metabolism , Light , Mixed Function Oxygenases/metabolism , Phosphoric Acids/chemistry , Reactive Oxygen Species/metabolism , Oxidation-Reduction/radiation effects , Sordariales/enzymology
9.
Nanotechnology ; 28(10): 105703, 2017 Mar 10.
Article in English | MEDLINE | ID: mdl-28085004

ABSTRACT

Using monochromated electron energy loss spectroscopy in a probe-corrected scanning transmission electron microscope we demonstrate band gap mapping in ZnO/ZnCdO thin films with a spatial resolution below 10 nm and spectral precision of 20 meV.

10.
Med Microbiol Immunol ; 206(1): 77-81, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27770276

ABSTRACT

The concept of zoonotic hepatitis E in industrialized countries has emerged with the discovery of swine strains of hepatitis E virus (HEV) genotype 3, closely related to human HEV. Different routes of zoonotic HEV transmission have been recognized, including contact with infected pigs. Workers occupationally exposed to swine (WOES) have been considered a risk group for HEV infection, but contradictory results have been reported. In the present study, we searched for anti-HEV IgG in WOES (butchers, slaughterhouse workers, veterinarians and pig farmers; n = 114) and in the general population (n = 804) in order to investigate the potential occupational risk of zoonotic HEV infection in this work group. A significantly higher (p = 0.008) anti-HEV IgG seroprevalence was found in WOES (30.7 %) when compared with the general population (19.9 %). Multivariate analysis showed that having professions with exposure to pigs for more than 16.5 years was a risk factor for being positive for anti-HEV IgG (aOR of 5.4, 95 % CI 1.9-15.6, p = 0.002). To our knowledge, this is the first study on the prevalence of anti-HEV IgG in WOES in Portugal, also showing increased probability for infection in this group.


Subject(s)
Animal Husbandry , Hepatitis Antibodies/blood , Hepatitis E virus/immunology , Hepatitis E/epidemiology , Occupational Exposure , Adult , Aged , Aged, 80 and over , Animals , Female , Humans , Immunoglobulin G/blood , Male , Middle Aged , Portugal , Seroepidemiologic Studies , Swine , Young Adult
11.
Biologicals ; 44(4): 276-280, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27329008

ABSTRACT

Evaluating new rare serious vaccine safety signals is difficult and complex work. To further assess the observed increase in narcolepsy cases seen in Europe with the 2009 pandemic H1N1 influenza vaccine, the International Alliance for Biological Standardization (IABS) invited a wide range of experts to a one day meeting in Geneva in October 2015 to present data and to discuss the implications. The presentations covered the following topics: clinical picture of childhood narcolepsy following the 2009 H1N1 pandemic vaccination campaigns; epidemiological studies conducted to assess the risk of narcolepsy, other neurological and immune-related diseases following 2009 pandemic H1N1 influenza vaccine; potential biases influencing the different epidemiological study designs; potential genetic contribution to the development of narcolepsy; potential biological mechanisms for development of narcolepsy in this setting including the role of the virus itself, antigenic differences between the vaccines and differences in AS03-adjuvanted vaccines. The presentations were followed by fulsome roundtable discussions. Members from affected families also attended and made informal comments to round out the day's deliberations. This meeting emphasized the value added in bringing together in a neutral setting a wide range of experts and vaccine producers to discuss such a complex new serious adverse event following immunization.


Subject(s)
Influenza A Virus, H1N1 Subtype/immunology , Influenza Vaccines/immunology , Influenza, Human/immunology , Narcolepsy/immunology , Adolescent , Child , Europe/epidemiology , Humans , Incidence , Influenza Vaccines/adverse effects , Influenza Vaccines/standards , Influenza, Human/prevention & control , Narcolepsy/epidemiology , Narcolepsy/etiology , Pandemics/prevention & control , Vaccination/adverse effects , Vaccination/methods , Vaccination/standards , Young Adult
12.
Nat Commun ; 7: 11134, 2016 Apr 04.
Article in English | MEDLINE | ID: mdl-27041218

ABSTRACT

Oxidative processes are essential for the degradation of plant biomass. A class of powerful and widely distributed oxidative enzymes, the lytic polysaccharide monooxygenases (LPMOs), oxidize the most recalcitrant polysaccharides and require extracellular electron donors. Here we investigated the effect of using excited photosynthetic pigments as electron donors. LPMOs combined with pigments and reducing agents were exposed to light, which resulted in a never before seen 100-fold increase in catalytic activity. In addition, LPMO substrate specificity was broadened to include both cellulose and hemicellulose. LPMO enzymes and pigment derivatives common in the environment of plant-degrading organisms thus form a highly reactive and stable light-driven system increasing the turnover rate and versatility of LPMOs. This light-driven system may find applications in biotechnology and chemical processing.


Subject(s)
Cellulose/chemistry , Chlorophyll/chemistry , Mixed Function Oxygenases/chemistry , Biomass , Catalysis/radiation effects , Oxidation-Reduction , Oxygen/chemistry
13.
Nanoscale ; 8(14): 7631-7, 2016 Apr 14.
Article in English | MEDLINE | ID: mdl-26987850

ABSTRACT

The spatial distribution of defect related deep band emission has been studied in zinc oxide (ZnO) nano- and microwires using depth resolved cathodoluminescence spectroscopy (DRCLS) in a hyperspectral imaging (HSI) mode within a UHV scanning electron microscope (SEM). Three sets of wires were examined that had been grown by pulsed laser deposition or vapor transport methods and ranged in diameter from 200 nm-2.7 µm. This data was analyzed by developing a 3D DRCLS simulation and using it to estimate the segregation depth and decay profile of the near surface defects. We observed different dominant defects from each growth process as well as diameter-dependent defect segregation behavior.

14.
Euro Surveill ; 20(29): 21192, 2015 Jul 23.
Article in English | MEDLINE | ID: mdl-26227370

ABSTRACT

In May 2013, Italy declared a national outbreak of hepatitis A, which also affected several foreign tourists who had recently visited the country. Molecular investigations identified some cases as infected with an identical strain of hepatitis A virus subgenotype IA. After additional European Union/European Economic Area (EU/EEA) countries reported locally acquired and travel-related cases associated with the same outbreak, an international outbreak investigation team was convened, a European outbreak case definition was issued and harmonisation of the national epidemiological and microbiological investigations was encouraged. From January 2013 to August 2014, 1,589 hepatitis A cases were reported associated with the multistate outbreak; 1,102 (70%) of the cases were hospitalised for a median time of six days; two related deaths were reported. Epidemiological and microbiological investigations implicated mixed frozen berries as the vehicle of infection of the outbreak. In order to control the spread of the outbreak, suspected or contaminated food batches were recalled, the public was recommended to heat-treat berries, and post-exposure prophylaxis of contacts was performed. The outbreak highlighted how large food-borne hepatitis A outbreaks may affect the increasingly susceptible EU/EEA general population and how, with the growing international food trade, frozen berries are a potential high-risk food.


Subject(s)
Disease Outbreaks , Food Contamination , Foodborne Diseases/epidemiology , Fruit/poisoning , Hepatitis A virus/genetics , Hepatitis A/epidemiology , Adolescent , Adult , Child, Preschool , Contact Tracing , Epidemiologic Studies , Europe/epidemiology , European Union , Female , Foodborne Diseases/diagnosis , Foodborne Diseases/virology , Frozen Foods/poisoning , Frozen Foods/virology , Fruit/virology , Hepatitis A/virology , Hepatitis A virus/isolation & purification , Humans , Male , Middle Aged , Surveys and Questionnaires
15.
Epidemiol Infect ; 143(11): 2269-78, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25420586

ABSTRACT

The aim of the European Sero-Epidemiology Network 2 (ESEN2) project was to estimate age-specific seroprevalence for a number of vaccine-preventable diseases in Europe. To achieve this serosurveys were collected by 22 national laboratories. To adjust for a variety of laboratory methods and assays, all quantitative results were transformed to a reference laboratory's units and were then classified as positive or negative to obtain age-specific seroprevalence. The aim of this study was to assess the value of standardization by comparing the crude and standardized seroprevalence estimates. Seroprevalence was estimated for measles, mumps, rubella, diphtheria, varicella zoster and hepatitis A virus (HAV) and compared before and after serological results had been standardized. The results showed that if no such adjustment had taken place, seroprevalence would have differed by an average of 3·2% (95% bootstrap interval 2·9-3·6) although this percentage varied substantially by antigen. These differences were as high as 16% for some serosurveys (HAV) which means that standardization could have a considerable impact on seroprevalence estimates and should be considered when comparing serosurveys performed in different laboratories using different assay methods.


Subject(s)
Chickenpox/epidemiology , Diphtheria Toxoid/therapeutic use , Diphtheria/epidemiology , Hepatitis A/epidemiology , Measles/epidemiology , Mumps/epidemiology , Rubella/epidemiology , Viral Vaccines/therapeutic use , Adolescent , Adult , Chickenpox/immunology , Chickenpox/prevention & control , Child , Child, Preschool , Diphtheria/immunology , Diphtheria/prevention & control , Diphtheria Toxoid/immunology , Europe/epidemiology , Hepatitis A/immunology , Hepatitis A/prevention & control , Humans , Infant , Measles/immunology , Measles/prevention & control , Mumps/immunology , Mumps/prevention & control , Reference Standards , Rubella/immunology , Rubella/prevention & control , Seroepidemiologic Studies , Viral Vaccines/immunology , Young Adult
16.
Euro Surveill ; 19(15)2014 Apr 17.
Article in English | MEDLINE | ID: mdl-24762662

ABSTRACT

On 7 March 2014, an increase in hepatitis A virus (HAV) infections was identified in Norway. As of 12 April, 19 cases of HAV infection with a virus strain identical to an ongoing European outbreak have been identified. Six probable cases are currently under investigation. On 11 April, a frozen berry mix cake imported from another European country was found as the likely source of the outbreak; the importer has withdrawn the product in Norway.


Subject(s)
Disease Outbreaks , Foodborne Diseases/epidemiology , Frozen Foods/virology , Fruit/virology , Hepatitis A virus/isolation & purification , Hepatitis A/epidemiology , Foodborne Diseases/etiology , Hepatitis A/virology , Hepatitis A virus/genetics , Humans , Interviews as Topic , Norway/epidemiology , Surveys and Questionnaires
17.
Parasitol Res ; 113(1): 387-90, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24233408

ABSTRACT

The objective of this study was to determine if human genotypes of Giardia lamblia could be found in canine companion animals from urban and peri-urban environments in Tucson, Arizona. Canine fecal samples collected from the Humane Society of Southern Arizona between July 2006 and April 2009 were screened for G. lamblia infection using immunofluorescent microscopy and confirmed by polymerase chain reaction (PCR). Of the 672 samples screened, 196 were found positive by IFA and 185 of those positive were successfully amplified through PCR. Sequencing analysis showed samples were primarily of the C or D genotypes (n =154), or showing a mix of the C and D genotypes (n =10). One sample showed a mixed infection of a human genotype (A) and a dog-specific genotype (C). These data are consistent with previous studies showing dog specific genotypes to be dominant in environments where dog-to-dog transmission is likely to occur, and provides further evidence that multiple genes should be targeted for more accurate genotype characterization.


Subject(s)
Dog Diseases/parasitology , Dogs/parasitology , Giardia lamblia/classification , Giardiasis/veterinary , Animals , Arizona/epidemiology , Dog Diseases/epidemiology , Feces/parasitology , Genotype , Giardia lamblia/genetics , Giardiasis/epidemiology , Humans , Polymerase Chain Reaction , Sequence Analysis, DNA
18.
Acta Neurol Scand ; 129(5): 300-6, 2014 May.
Article in English | MEDLINE | ID: mdl-23937295

ABSTRACT

OBJECTIVE: The aim of the study was to examine the sense of smell in LRRK2 mutation carriers and in patients with sporadic PD (sPD). MATERIALS AND METHODS: A total of 343 individuals were included: 275 sPD of whom 90 were de novo patients with sPD, 17 LRRK2 PD, 36 healthy LRRK2 mutation carriers, and 15 healthy family members without mutation. All subjects underwent neurologic examination and olfactory sense testing with B-SIT (a 12-item test). Linear regression analysis was applied to build different models with B-SIT as dependent variable. RESULTS: Sporadic PD had significantly lower scores in olfaction compared with LRRK2 PD (P < 0.001). B-SIT scores were lowest in medicated sPD, and higher scores were found in de novo patients. LRRK2 PD had similar sense of smell to healthy LRRK2 mutation carriers and to healthy family members without mutation when adjusting for age. CONCLUSION: Hyposmia was pronounced already at time of diagnosis in the sPD cases but was not present in healthy LRRK2 mutation carriers and less pronounced in LRRK2 PD compared with sporadic cases. Smell testing may be a preclinical marker in sporadic PD but does not seem applicable in LRRK2 cases.


Subject(s)
Olfaction Disorders/complications , Olfaction Disorders/genetics , Parkinson Disease/complications , Parkinson Disease/genetics , Protein Serine-Threonine Kinases/genetics , Age Factors , Cross-Sectional Studies , Family , Female , Genetic Predisposition to Disease , Heterozygote , Humans , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2 , Male , Middle Aged , Mutation , Sex Factors
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