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1.
J Neuroendocrinol ; : e13424, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38960698

ABSTRACT

The impact of heat stress (HS) on production is intricately linked with feed intake. We investigated the effects of HS on intestines and diencephalic genes in Pekin ducks. One hundred and sixty adult ducks were allocated to two treatment rooms. The control room was maintained at 22°C and the HS room at 35°C for the first 10 h of the day then reduced to 29.5°C. After 3 weeks, 10 hens and 5 drakes were euthanized from each room and jejunum and ileum collected for histology. Brains were collected for gene expression analysis using qRT-PCR. Intestinal morphology data were analyzed with two-way ANOVA and diencephalic gene data were analyzed with Kruskal-Wallis test. There was an increase in villi width in the ileum (p = .0136) and jejunum (p = .0019) of HS hens compared to controls. HS drakes showed a higher crypt depth (CD) in the jejunum (p = .0198) compared to controls. There was an increase in crypt goblet cells (GC) count in the ileum (p = .0169) of HS drakes compared to HS hens. There was higher villi GC count (p = .07) in the jejunum of HS drakes compared to controls. There was an increase in the crypt GC density (p = .0054) in the ileum, not jejunum, of HS drakes compared to HS hens. Further, there were no differences in the proopiomelanocortin gene expression in either sex but there was an increase in the expression of neuropeptide Y (NPY) gene in HS hens (p = .031) only and a decrease in the corticotropin releasing hormone gene in the HS drakes (p = .037) compared to controls. These data show that there are sex differences in the effect of HS on gut morphology while the upregulation in NPY gene may suggest a role in mediating response to chronic HS.

2.
Poult Sci ; 103(5): 103588, 2024 May.
Article in English | MEDLINE | ID: mdl-38479100

ABSTRACT

Preening cups are a form of environmental enrichment that provides Pekin ducks a semi-open water source to express their natural behaviors. We recently observed that preening cups may increase feather pecking behaviors in ducks. Thus, we set out to determine if this form of enrichment can impact the affective state of Pekin ducks. To accomplish this goal, we evaluated the effect of preening cups on serotonin (5-HT) and dopamine (DA) turnover via mass spectrometry and their respective synthetic enzyme gene expression via qRT-PCR. Our study investigated the link between aggressive pecking with levels and activity of brain 5-HT and DA. Brain 5-HT and DA levels and activity have been established for decades to be associated with affective states. Grow-out Pekin ducks (n = 260) were housed at Purdue and raised per industry standards. On day 18, brains were collected from ducks in pens before preening cups were placed (PRE, n = 6) and, again on day 43, in pens with (PC, n = 6) and without (CON, n = 6) preening cups. Brains were dissected into right and left halves, then further microdissected into 4 brain areas: caudal mesencephalon (CM), rostral mesencephalon (RM), diencephalon (DI), and forebrain (FB). The right hemisphere was used for mass spectrometry to determine the neurotransmitter concentration (ng/mg of tissue) and those concentrations were applied to neurotransmitter turnover equations. There were no differences across treatments for 5-HT turnover in any brain area. There were differences in DA turnover across age (P = 0.0067) in the CM and across treatments (P = 0.003) in the RM. The left hemisphere of the brain was used to perform qRT-PCR on the genes of 5-HT and DA production enzymes. Within the CM, day 43 duck brains had increased (P = 0.022) tryptophan hydroxylase and tyrosine hydroxylase relative mRNA levels. All other brain areas showed no differences. Our data suggest that ducks housed with preening cups and that showed increased feather pecking are associated with increased brain DA activity. The increased DA in the brain may lead to a predisposition for increased aggression in the form of feather pecking.


Subject(s)
Brain , Dopamine , Ducks , Housing, Animal , Serotonin , Animals , Ducks/physiology , Dopamine/metabolism , Serotonin/metabolism , Brain/metabolism , Brain/physiology , Behavior, Animal/physiology , Aggression/physiology , Male , Animal Husbandry/methods , Feathers/chemistry
3.
Diabetes Metab ; 48(6): 101395, 2022 11.
Article in English | MEDLINE | ID: mdl-36184047

ABSTRACT

Prediabetes is a very prevalent condition associated with an increased risk of developing diabetes and/or other chronic complications, in particular cardiovascular disorders. Early detection is therefore mandatory since therapeutic interventions may limit the development of these complications. Diagnosis of prediabetes is currently based on glycemic criteria (fasting plasma glucose (PG), and/or glycemia at 120 min during a 75 g oral glucose tolerance test (OGTT) and/or glycated hemoglobin (HbA1c). Accumulating longitudinal evidence suggests that a 1-hour PG ≥155 mg/dl (8.6 mmol/l) during the OGTT is an earlier marker of prediabetes than fasting PG, 2-h post-load PG, or HbA1c. There is substantial evidence demonstrating that the 1-h post-load PG is a more sensitive predictor of type 2 diabetes, cardiovascular disease, microangiopathy and mortality compared with conventional glucose criteria. The aim of this review is to highlight the paramount importance of detecting prediabetes early in its pathophysiological course. Accordingly, as recommended by an international panel in a recent petition, 1-h post-load PG could replace current criteria for diagnosing early stages of "prediabetes" before prediabetes evolves as conventionally defined.


Subject(s)
Cardiovascular Diseases , Diabetes Mellitus, Type 2 , Prediabetic State , Humans , Blood Glucose , Glycated Hemoglobin/analysis , Diabetes Mellitus, Type 2/diagnosis , Prediabetic State/diagnosis , Glucose Tolerance Test
4.
QJM ; 115(10): 653-660, 2022 Oct 25.
Article in English | MEDLINE | ID: mdl-35092293

ABSTRACT

BACKGROUND: Bone mineral deficits are one of the most common complications in cancer survivors. However, there are no studies evaluating bone mineral density (BMD) and the prevalence of osteopenia and osteoporosis among patients with different types of cancers. AIM: The objective was to assess BMD and evaluate the prevalence of osteopenia and osteoporosis among US adults with cancer. DESIGN: A cross-section propensity score matching study. METHODS: We extracted data from National Health and Nutrition Examination Survey database from 2005 to 2018. We compared BMD in participants with and without cancer which was further analyzed according to cancer type. We conducted logistic regression to evaluate adjusted odds ratios of osteopenia and osteoporosis and determine risk factors for their development. RESULTS: We found that BMD was significantly higher in participants without cancer than cancer patients. Furthermore, the median BMD of patients with breast cancer or skin cancer (including melanoma) was significantly lower than participants without cancer. People with breast, lung, genitourinary and skin cancers were more likely to incur osteopenia/osteoporosis than those without cancer. CONCLUSIONS: BMD differs depending upon type in survivors. Individuals with a history of cancer have a poor understanding of osteoporosis and its risk factors. Understanding risk factors in patients with cancers identified in our study may be helpful for preventing osteoporosis and fractures and the development of screening guidelines.


Subject(s)
Bone Diseases, Metabolic , Neoplasms , Osteoporosis , Humans , Bone Density , Nutrition Surveys , Bone Diseases, Metabolic/epidemiology , Osteoporosis/epidemiology , Osteoporosis/etiology , Odds Ratio , Neoplasms/epidemiology
5.
Psychol Med ; 52(2): 303-313, 2022 01.
Article in English | MEDLINE | ID: mdl-32538342

ABSTRACT

BACKGROUND: Classic theories posit that depression is driven by a negative learning bias. Most studies supporting this proposition used small and selected samples, excluding patients with comorbidities. However, comorbidity between psychiatric disorders occurs in up to 70% of the population. Therefore, the generalizability of the negative bias hypothesis to a naturalistic psychiatric sample as well as the specificity of the bias to depression, remain unclear. In the present study, we tested the negative learning bias hypothesis in a large naturalistic sample of psychiatric patients, including depression, anxiety, addiction, attention-deficit/hyperactivity disorder, and/or autism. First, we assessed whether the negative bias hypothesis of depression generalized to a heterogeneous (and hence more naturalistic) depression sample compared with controls. Second, we assessed whether negative bias extends to other psychiatric disorders. Third, we adopted a dimensional approach, by using symptom severity as a way to assess associations across the sample. METHODS: We administered a probabilistic reversal learning task to 217 patients and 81 healthy controls. According to the negative bias hypothesis, participants with depression should exhibit enhanced learning and flexibility based on punishment v. reward. We combined analyses of traditional measures with more sensitive computational modeling. RESULTS: In contrast to previous findings, this sample of depressed patients with psychiatric comorbidities did not show a negative learning bias. CONCLUSIONS: These results speak against the generalizability of the negative learning bias hypothesis to depressed patients with comorbidities. This study highlights the importance of investigating unselected samples of psychiatric patients, which represent the vast majority of the psychiatric population.


Subject(s)
Depression , Reversal Learning , Anxiety Disorders/epidemiology , Depression/epidemiology , Humans , Punishment , Reward
6.
Int J Oral Maxillofac Surg ; 50(11): 1440-1442, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33658150

ABSTRACT

Functional and aesthetic rehabilitation of exophthalmos in stable thyroid eye disease (TED) can be achieved with a variety of surgical approaches. This article illustrates modifications of the classic transantral technique to provide a graded orbital decompression and achieve improved cosmesis. A retrospective chart review was performed of stable TED patients who elected to undergo the modified transantral decompression; illustrative cases are described. This modified transantral orbital decompression allows for graded orbital decompression surgery, adding to the range of treatment options for stable TED patients.


Subject(s)
Exophthalmos , Graves Ophthalmopathy , Decompression, Surgical , Esthetics, Dental , Exophthalmos/surgery , Graves Ophthalmopathy/surgery , Humans , Orbit/surgery , Retrospective Studies
7.
J Autism Dev Disord ; 51(11): 4213-4226, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33491119

ABSTRACT

Heightened attention towards negative information is characteristic of depression. Evidence is emerging for a negative attentional bias in Autism spectrum disorder (ASD), perhaps driven by the high comorbidity between ASD and depression. We investigated whether ASD is characterised by a negative attentional bias and whether this can be explained by comorbid (sub) clinical depression. Participants (n = 116) with current (CD) or remitted depression (RD) and/or ASD, and 64 controls viewed positively and negatively valenced (non-)social pictures. Groups were compared on three components of visual attention using linear mixed models. Both CD individuals with and without ASD, but not remitted depressed and never-depressed ASD individuals showed a negative bias, suggesting that negative attentional bias might be a depressive state-specific marker for depression in ASD.


Subject(s)
Attentional Bias , Autism Spectrum Disorder , Autism Spectrum Disorder/epidemiology , Depression/diagnosis , Depression/epidemiology , Emotions , Eye-Tracking Technology , Humans
8.
S Afr Med J ; 111(8): 741-746, 2021 Jul 02.
Article in English | MEDLINE | ID: mdl-35227354

ABSTRACT

BACKGROUND: Pulmonary embolism (PE) is a known complication of COVID-19 disease. The mechanism of thromboembolic events appears to be stimulated by excessive thrombin production, inhibition of fibrinolysis and deposition of antiphospholipids and thrombi, as well as microvascular dysfunction in multiple vascular beds. The occurrence of PE has been well demonstrated in hospitalised patients with severe disease. Very few data are available on its incidence or prevalence in non-hospitalised patients diagnosed with a milder form of the disease. OBJECTIVES: To assess the prevalence of PE in non-hospitalised patients diagnosed with mild COVID-19 who presented with raised D-dimer levels and persistent or new-onset cardiopulmonary symptoms. METHODS: This was a retrospective study conducted in the Department of Nuclear Medicine at Universitas Academic Hospital, Bloemfontein, South Africa. We reviewed the studies of 65 non-hospitalised patients with COVID-19 referred to the department from July 2020 to January 2021 for a perfusion-only single-photon emission computed tomography/computed tomography (SPECT/CT) study or a ventilation/perfusion (VQ) SPECT/CT study. All 65 patients had raised D-dimer levels with persistent, worsening or new-onset cardiopulmonary symptoms after the diagnosis of COVID-19. RESULTS: Sixty-five patients were studied. The median (interquartile range) age was 46 (41 - 54) years and the majority (88.2%) were female. There were 22 patients (33.8%) with lung perfusion defects in keeping with PE. Two of these patients had a false-negative computed tomography pulmonary angiography (CTPA) study for PE performed the same day as their VQ SPECT/CT study. CONCLUSIONS: We confirm a high prevalence of PE in non-hospitalised patients diagnosed with mild COVID-19 who presented with raised D-dimer levels and persistent or new-onset cardiopulmonary symptoms. We recommend that irrespective of disease severity, hospitalised and non-hospitalised patients with COVID-19 presenting with persistent or new-onset cardiopulmonary symptoms and raised D-dimer levels should be investigated further for PE.


Subject(s)
COVID-19/complications , Pulmonary Embolism/diagnosis , Adult , COVID-19/epidemiology , Cohort Studies , Female , Humans , Male , Middle Aged , Prevalence , Pulmonary Embolism/epidemiology , Retrospective Studies , South Africa/epidemiology
9.
J Affect Disord ; 274: 1165-1172, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32663947

ABSTRACT

BACKGROUND: Negative memory bias is a strong risk factor for the development and maintenance of depression. Recent evidence also found negative memory bias in other mental disorders. Here, we aim to: 1) assess the presence and strength of negative memory bias in a range of (comorbid) mental disorders, 2) investigate which disorder-specific symptoms are associated with negative memory bias, and 3) test whether negative memory bias might be a transdiagnostic mechanism. METHODS: Negative memory bias was measured in patients with at least one diagnosis of a stress-related disorder (n = 86), a neurodevelopmental disorder (n = 53), or both (n = 68), and 51 controls. Depression, anxiety, attention-deficit/hyperactivity disorder, and autism spectrum disorder symptom severity was assessed using questionnaires. Groups were compared on negative memory bias and the associations between negative memory bias and symptom severity were made using linear regression models. RESULTS: All patient groups showed stronger negative memory bias than the controls. Negative memory bias was individually associated with all symptom severity indices, but when added into a single model, only the association with depressive symptom severity remained. This persisted after controlling for diagnostic group. LIMITATIONS: Due to the cross-sectional sectional study design, we could only look at the associations between negative memory bias and disorder-specific symptoms and not at the direction of the effects. CONCLUSIONS: Negative memory bias is characteristic of a depressotypic processing style and present in different mental disorders. It might play a mechanistic role in the development of (subclinical) co-occurrence between mental disorders.


Subject(s)
Autism Spectrum Disorder , Depression , Anxiety Disorders , Cognition , Cross-Sectional Studies , Humans
10.
Front Psychiatry ; 11: 569946, 2020.
Article in English | MEDLINE | ID: mdl-33679459

ABSTRACT

Alexithymia-reflecting deficits in cognitive emotion processing-is highly prevalent in individuals with depressive disorders. Subsequently, mixed evidence for attentional bias is found in these individuals. Alexithymia may be a potential influencing factor for attentional bias in depression. In the current study, 83 currently depressed (CD) and 76 never-depressed (ND) controls completed an eye-tracker task consisting of valenced (non)-social pictures. Alexithymia scores were also included as a moderator as both a continuous and categorical measure (so high vs. low alexithymia). No group difference or moderating effect of alexithymia was found on attentional bias. Thus, alexithymic symptoms, included both dimensionally and categorically, may not influence biased attentional processing in depression compared to ND individuals. Thus, it is important to explore other potential explaining factors for the equivocal results found on biased attentional processing of emotional information in depression.

11.
Sci Rep ; 8(1): 7215, 2018 05 08.
Article in English | MEDLINE | ID: mdl-29740112

ABSTRACT

Although the cultivation of transgenic plants expressing toxins of Bacillus thuringiensis (Bt) represents a successful pest management strategy, the rapid evolution of resistance to Bt plants in several lepidopteran pests has threatened the sustainability of this practice. By exhibiting a favorable safety profile and allowing integration with pest management initiatives, plant essential oils have become relevant pest control alternatives. Here, we assessed the potential of essential oils extracted from a Neotropical plant, Siparuna guianensis Aublet, for improving the control and resistance management of key lepidopteran pests (i.e., Spodoptera frugiperda and Anticarsia gemmatalis). The essential oil exhibited high toxicity against both lepidopteran pest species (including an S. frugiperda strain resistant to Cry1A.105 and Cry2Ab Bt toxins). This high insecticidal activity was associated with necrotic and apoptotic effects revealed by in vitro assays with lepidopteran (but not human) cell lines. Furthermore, deficits in reproduction (e.g., egg-laying deterrence and decreased egg viability), larval development (e.g., feeding inhibition) and locomotion (e.g., individual and grouped larvae walking activities) were recorded for lepidopterans sublethally exposed to the essential oil. Thus, by similarly and efficiently controlling lepidopteran strains susceptible and resistant to Bt toxins, the S. guianensis essential oil represents a promising management tool against key lepidopteran pests.


Subject(s)
Insecticide Resistance/drug effects , Insecticides/pharmacology , Laurales/chemistry , Moths/drug effects , Oils, Volatile/pharmacology , Spodoptera/drug effects , Animals , Bacillus thuringiensis/chemistry , Bacillus thuringiensis Toxins , Bacterial Proteins/isolation & purification , Bacterial Proteins/pharmacology , Cell Line , Endotoxins/isolation & purification , Endotoxins/pharmacology , Hemolysin Proteins/isolation & purification , Hemolysin Proteins/pharmacology , Insecticides/isolation & purification , Larva/drug effects , Larva/physiology , Locomotion/drug effects , Locomotion/physiology , Moths/physiology , Oils, Volatile/isolation & purification , Pest Control, Biological/methods , Spodoptera/physiology , Zygote/drug effects , Zygote/physiology
13.
Neuromuscul Disord ; 27(3): 243-250, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28082206

ABSTRACT

Myalgia, fatigue, and exercise intolerance are cause for referral to a neurologist. However, the diagnostic value of history, neurological examination, and ancillary investigations in patients with these symptoms is unknown. This study provides a sound footing for deciding which ancillary investigations should be conducted. A prospective observational study of the diagnostic approach in 187 patients with myalgia, exercise intolerance, or fatigue as their predominant symptom was performed. The primary outcomes were independent contribution of referral letter, history, examination, and ancillary investigations to a myopathy diagnosis. The secondary outcome was diagnostic value of combined ancillary investigations. 27% of patients had a myopathy. Positive family history (OR 3.2), progressive symptoms (OR 2.2), atrophy (OR 9.7), weakness (OR 10.9), and hyporeflexia (OR 4.4) were associated with a myopathy. Positive predictive values for myopathy were calculated for CK (0.32), EMG (0.66), ultrasound (0.47), and muscle biopsy (0.78). All contributed significantly in predicting myopathy. Multivariate analysis yielded a diagnostic algorithm facilitating a more efficient work-up in future patients. CK levels, EMG, ultrasound, and muscle biopsy independently contribute to predicting a myopathy. The diagnostic algorithm shows which combination of ancillary investigations should be employed in different subgroups and when to omit invasive techniques. This algorithm may drastically improve diagnostic efficiency.


Subject(s)
Fatigue/diagnosis , Muscular Diseases/diagnosis , Myalgia/diagnosis , Adult , Creatine Kinase/blood , Fatigue/etiology , Female , Humans , Male , Middle Aged , Muscular Diseases/blood , Muscular Diseases/complications , Myalgia/etiology
14.
Soft Matter ; 12(48): 9705-9727, 2016 Dec 06.
Article in English | MEDLINE | ID: mdl-27808335

ABSTRACT

The determination of the net charge and size of microgel particles as a function of their concentration, as well as the degree of association of ions to the microgel backbone, has been pursued in earlier studies mainly by scattering and rheology. These methods suffer from contributions due to inter-particle interactions that interfere with the characterization of single-particle properties. Here we introduce dielectric spectroscopy as an alternative experimental method to characterize microgel systems. The advantage of dielectric spectroscopy over other experimental methods is that the polarization due to mobile charges within a microgel particle is only weakly affected by inter-particle interactions. Apart from electrode polarization effects, experimental spectra on PNIPAM-co-AA [poly(N-isopropylacrylamide-co-acrylic acid)] ionic microgel particles suspended in de-ionized water exhibit three well-separated relaxation modes, which are due to the polarization of the mobile charges within the microgel particles, the diffuse double layer around the particles, and the polymer backbone. Expressions for the full frequency dependence of the electrode-polarization contribution to the measured dielectric response are derived, and a theory is proposed for the polarization resulting from the mobile charges within the microgel. Relaxation of the diffuse double layer is modeled within the realm of a cell model. The net charge and the size of the microgel particles are found to be strongly varying with concentration. A very small value of the diffusion coefficient of ions within the microgel is found, due to a large degree of chemical association of protons to the polymer backbone.

15.
Diabet Med ; 33(8): 1060-6, 2016 08.
Article in English | MEDLINE | ID: mdl-26996391

ABSTRACT

AIMS: The relationship between 1- and 2-h glucose levels following an oral glucose tolerance test (OGTT) and long-term mortality was evaluated. METHODS: Over a 33-year period, 2138 individuals were followed for all-cause mortality. Fasting and post-OGTT glucose parameters categorized the cohort according to baseline glycaemic status. Four categories were established according to 1- and 2-h glucose levels (in mmol/l): group A = 1 h ≤ 8.8 and 2 h < 7.8; group B = 1 h > 8.6 and 2 h < 7.8; group C = 1 h ≤ 8.6 and 2 h = 7.8-11.1 (impaired glucose tolerance); group D = 1 h > 8.6 and 2 h = 7.8-11.1 (impaired glucose tolerance). Individuals with diabetes at baseline were excluded from the cohort. RESULTS: By August 2013, 51% of the study cohort had died. The worst prognosis occurred in group D (73.8% mortality), followed by groups C (67.5%), B and A (57.9% and 41.6%, respectively). When the 2-h glucose value is 'normal' (< 7.8 mmol/l), the 1-h glucose value > 8.6 mmol/l is an important predictor of mortality (28% increased risk) compared with group A, controlling for sex, age, smoking, BMI, systolic and diastolic blood pressures. A gradual increased hazard for mortality was seen by study group (hazard ratio = 1.28, 1.60 and 1.76, for groups B, C and D, respectively; group A = reference). CONCLUSIONS: A 1-h glucose value > 8.6 mmol/l predicts mortality even when the 2-h level is < 7.8 mmol/l. However, when the 2-h level is in the impaired glucose tolerance range, the hazard for mortality rises significantly independent of the 1-h value. Individuals at risk for developing diabetes could be identified earlier using the 1-h threshold value of 8.6 mmol/l, which could avert progression to diabetes and increased mortality.‬.


Subject(s)
Blood Glucose/metabolism , Glucose Intolerance/epidemiology , Mortality , Adult , Cause of Death , Female , Follow-Up Studies , Glucose Intolerance/metabolism , Glucose Tolerance Test , Humans , Insulin/metabolism , Israel/epidemiology , Male , Middle Aged , Prognosis , Proportional Hazards Models , Time Factors
16.
J Nanotechnol Mater Sci ; 2(2): 1-6, 2015 Sep 07.
Article in English | MEDLINE | ID: mdl-26273701

ABSTRACT

This study compared the simulated workplace protection factors (SWPFs) between NIOSH-approved N95 respirators and P100 respirators, including two models of filtering facepiece respirator (FFR) and two models of elastomeric half-mask respirator (EHR), against sodium chloride particles (NaCl) in a range of 10 to 400 nm. Twenty-five human test subjects performed modified OSHA fit test exercises in a controlled laboratory environment with the N95 respirators (two FFR models and two EHR models) and the P100 respirators (two FFRs and two EHRs). Two Scanning Mobility Particle Sizers (SMPS) were used to measure aerosol concentrations (in the 10-400 nm size range) inside (Cin) and outside (Cout) of the respirator, simultaneously. SWPF was calculated as the ratio of Cout to Cin. The SWPF values obtained from the N95 respirators were then compared to those of the P100 respirators. SWPFs were found to be significantly different (P<0.05) between N95 and P100 class respirators. The 10th, 25th, 50th, 75th and 90th percentiles of the SWPFs for the N95 respirators were much lower than those for the P100 models. The N95 respirators had 5th percentiles of the SWPFs > 10. In contrast, the P100 class was able to generate 5th percentiles SWPFs > 100. No significant difference was found in the SWPFs when tested against nano-size (10 to 100 nm) and large-size (100 to 400 nm) particles. Overall, the findings suggest that the two FFRs and two EHRs with P100 class filters provide better performance than those with N95 filters against particles from 10 to 400 nm, supporting current OSHA and NIOSH recommendations.

17.
Rev Sci Instrum ; 86(3): 033706, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25832237

ABSTRACT

An Atomic Force Microscope (AFM) has been integrated in a miniature high-pressure flow reactor for in-situ observations of heterogeneous catalytic reactions under conditions similar to those of industrial processes. The AFM can image model catalysts such as those consisting of metal nanoparticles on flat oxide supports in a gas atmosphere up to 6 bar and at a temperature up to 600 K, while the catalytic activity can be measured using mass spectrometry. The high-pressure reactor is placed inside an Ultrahigh Vacuum (UHV) system to supplement it with standard UHV sample preparation and characterization techniques. To demonstrate that this instrument successfully bridges both the pressure gap and the materials gap, images have been recorded of supported palladium nanoparticles catalyzing the oxidation of carbon monoxide under high-pressure, high-temperature conditions.

18.
Clin Exp Rheumatol ; 32(5 Suppl 85): S-47-54, 2014.
Article in English | MEDLINE | ID: mdl-25365089

ABSTRACT

The 7 Core Data Set measures to assess rheumatoid arthritis (RA) were analysed for their relative efficiencies to distinguish active from control treatments in 9 comparisons of 5 agents, methotrexate, leflunomide, infliximab, adalimumab, and abatacept, in 8 clinical trials. Among the 7 measures, levels of relative efficiencies were in a similar range, highest for the physician global estimate, followed by, in order, patient global estimate, physical function on a health assessment questionnaire (HAQ), pain, swollen joint count (SJC), an acute phase reactant laboratory test - erythrocyte sedimentation (ESR) or C-reactive protein (CRP), and tender joint count (TJC). Comparisons of only 3 measures, SJC and ESR/CRP (regarded as optimal indicators of inflammation) and HAQ function (regarded as most likely to be affected by joint damage and therefore least reversible) indicated relative efficiencies for HAQ function at least as great as for SJC or ESR/CRP, although 8 of the nine comparisons involved patients with disease duration > 6.9 years. The findings indicate a strong rationale for a Core Data Set of 7 measures, as no single measure was clearly superior in relative efficiency in all clinical trials. At the same time, 'objective' laboratory ESR/CRP, TJC and SJC were not superior to 'subjective' global estimates of the physician or patient or patient self-report measures of physical function or pain, to differentiate active from control treatments. The findings challenge a traditional view that laboratory and clinical examination findings are more robust than patient self-report scores and physician global estimates to assess and monitor RA patients.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/diagnosis , Arthritis, Rheumatoid/drug therapy , Clinical Trials as Topic , Joints/drug effects , Rheumatology/methods , Arthritis, Rheumatoid/blood , Arthritis, Rheumatoid/physiopathology , Biomarkers/blood , Biomechanical Phenomena , Blood Sedimentation , C-Reactive Protein/metabolism , Health Status , Health Status Indicators , Humans , Joints/pathology , Joints/physiopathology , Middle Aged , Pain Measurement , Physical Examination , Predictive Value of Tests , Severity of Illness Index , Treatment Outcome
19.
Rev Sci Instrum ; 85(8): 083703, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25173272

ABSTRACT

To enable atomic-scale observations of model catalysts under conditions approaching those used by the chemical industry, we have developed a second generation, high-pressure, high-temperature scanning tunneling microscope (STM): the ReactorSTM. It consists of a compact STM scanner, of which the tip extends into a 0.5 ml reactor flow-cell, that is housed in a ultra-high vacuum (UHV) system. The STM can be operated from UHV to 6 bars and from room temperature up to 600 K. A gas mixing and analysis system optimized for fast response times allows us to directly correlate the surface structure observed by STM with reactivity measurements from a mass spectrometer. The in situ STM experiments can be combined with ex situ UHV sample preparation and analysis techniques, including ion bombardment, thin film deposition, low-energy electron diffraction and x-ray photoelectron spectroscopy. The performance of the instrument is demonstrated by atomically resolved images of Au(111) and atom-row resolution on Pt(110), both under high-pressure and high-temperature conditions.

20.
J Dairy Sci ; 97(7): 4269-80, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24819133

ABSTRACT

Differences in adoption of selected practices used in welfare assessment and audit programs were contrasted among organic (ORG; n=192) herds and similarly sized conventional grazing herds (CON-GR; n=36), and conventional nongrazing herds (CON-NG; n=64). Criteria from 3 programs were assessed: American Humane Association Animal Welfare Standards for Dairy Cattle, Farmers Assuring Responsible Management (FARM), and the Canadian Codes of Practice (CCP). Data were collected by trained study personnel during a herd visit and included information about neonatal care, dehorning, pain relief, calf nutrition, weaning, record keeping, use of veterinarians, and animal observations. Associations of management type (ORG, CON-GR, or CON-NG) with adoption of selected practice were assessed. Almost all farms (97%) met criteria suggested for age at weaning but fewer CON-NG farmers weaned calves at ≥5 wk of age compared with ORG and CON-GR farmers. Only 23% of farms met program requirements for use of pain relief during dehorning, and fewer CON-NG farmers used pain relief for calves after dehorning compared with ORG and CON-GR farmers. Calves on ORG farms were fed a greater volume of milk and were weaned at an older age than calves on CON-GR and CON-NG farms. Calves on CON-GR farms were dehorned at a younger age compared with calves on ORG and CON-NG farms. The calving area was shared with lactating cows for a larger proportion of ORG herds compared with conventional herds. About 30% of herds met welfare program criteria for body condition score but only about 20% met criteria for animal hygiene scores. The least proportion of cows with hock lesions was observed on ORG farms. Regular use of veterinarians was infrequent for ORG herds. Results of this study indicate that most of the organic and conventional farms enrolled in this study would have been unlikely to achieve many criteria of audit and assessment programs currently used in the US dairy industry.


Subject(s)
Animal Welfare , Cattle/physiology , Dairying/methods , Organic Agriculture/methods , Animals , Cattle/growth & development , Female , New York , Oregon , Wisconsin
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