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1.
J Transp Health ; 242022 Mar.
Article in English | MEDLINE | ID: mdl-34926159

ABSTRACT

INTRODUCTION: Greater transit use is associated with higher levels of physical activity, which is associated with lower health risks and better health outcomes. However, there is scant evidence about whether health care costs differ based on level of transit ridership. METHODS: A sample (n=947) of members of Kaiser Permanente in the Portland, Oregon area were surveyed in 2015 about their typical use of various modes of travel including transit. Electronic medical record-derived health care costs were obtained among these members for the prior three years. Analysis examined proportional costs between High transit users (3+ days/week), Low transit users (1-2 days/week), and Non-users adjusting for age and sex, and then individually (base models) and together for demographic and health status variables. RESULTS: In separate base models across individual covariates, High transit users had lower total health care costs (59-69% of Non-user's costs) and medication costs (31-37% of Non-users' costs) than Non-users. Low transit users also had lower total health care (69%-76% of Non-users' costs) and medication costs (43-57% transit of Non-user's costs) than Non-users. High transit users' outpatient costs were also lower (77-82% of Non-users). In fully-adjusted models, total health care and medication costs were lower among High transit users' (67% and 39%) and Low transit users' (75% and 48%) compared to Non-users, but outpatient costs did not differ by transit use. CONCLUSIONS: Findings have implications for the potential cost benefit of encouraging and supporting more transit use, although controlled longitudinal and experimental evidence is needed to confirm findings and understand mechanisms.

2.
BMC Pregnancy Childbirth ; 21(1): 205, 2021 Mar 12.
Article in English | MEDLINE | ID: mdl-33711957

ABSTRACT

BACKGROUND: Recent UK maternity policy changes recommend that a named midwife supports women throughout their pregnancy, birth and postnatal care. Whilst many studies report high levels of satisfaction amongst women receiving, and midwives providing, this level of continuity of carer, there are concerns some midwives may experience burnout and stress. In this study, we present a qualitative evaluation of the implementation of a midwife-led continuity of carer model that excluded continuity of carer at the birth. METHODS: Underpinned by the Conceptual Model for Implementation Fidelity, our evaluation explored the implementation, fidelity, reach and satisfaction of the continuity of carer model. Semi-structured interviews were undertaken with midwives (n = 7) and women (n = 15) from continuity of carer team. To enable comparisons between care approaches, midwives (n = 7) and women (n = 10) from standard approach teams were also interviewed. Interviews were recorded, transcribed and analysed using thematic analysis. RESULTS: For continuity of carer team midwives, manageable caseloads, extended appointment times, increased team stability, and flexible working patterns facilitated both care provided and midwives' job satisfaction. Both continuity of carer and standard approach midwives reported challenges in providing postnatal continuity given the unpredictable timing of labour and birth. Time constraints, inadequate staffing and lack of administrative support were reported as additional barriers to implementing continuity of carer within standard approach teams. Women reported continuity was integral to building trust with midwives, encouraged them to disclose mental health issues and increased their confidence in making birth choices. CONCLUSIONS: Our evaluation highlighted the successful implementation of a continuity of carer model for ante and postnatal care. Despite exclusion of the birth element in the model, both women and midwives expressed high levels of satisfaction in comparison to women and midwives within the standard approach. Implementation successes were largely due to structural and resource factors, particularly the combination of additional time and smaller caseloads of women. However, these resources are not widely available within the resources of maternity unit budgets. Future research should further explore whether a continuity of carer model focusing on antenatal and postnatal care delivery is a feasible and sustainable model of care for all women.


Subject(s)
Continuity of Patient Care , Maternal Health Services , Midwifery , Nurse Midwives/psychology , Patient Preference , Perinatal Care , Adult , Attitude of Health Personnel , Continuity of Patient Care/organization & administration , Continuity of Patient Care/trends , Female , Humans , Maternal Health Services/organization & administration , Maternal Health Services/standards , Midwifery/methods , Midwifery/organization & administration , Models, Organizational , Organizational Innovation , Parturition/psychology , Patient Preference/psychology , Patient Preference/statistics & numerical data , Perinatal Care/methods , Perinatal Care/trends , Pregnancy , Qualitative Research , Social Support , United Kingdom
3.
Mol Cell Probes ; 56: 101695, 2021 04.
Article in English | MEDLINE | ID: mdl-33453365

ABSTRACT

Researchers have developed multiple methods to characterize clinical and environmental strains of Vibrio vulnificus. The aim of our study was to use four assays to detect virulence factors in strains from infected patients and those from surface waters/sediments/oysters of South Carolina and the Gulf of Mexico. Vibrio vulnificus strains from clinical (n = 81) and environmental (n = 171) sources were tested using three real-time PCR methods designed to detect polymorphisms in the 16S rRNA, vcg and pilF genes and a phenotypic method, the ability to ferment D-mannitol. Although none of the tests correctly categorized all isolates, the differentiation between clinical and environmental isolates was similar for the pilF, vcgC/E and 16S rRNA assays, with sensitivities of 74.1-79.2% and specificities of 77.4-82.7%. The pilF and vcgC/E assays are comparable in efficacy to the widely used 16S rRNA method, while the D-mannitol fermentation test is less discriminatory (sensitivity = 77.8%, specificity = 61.4%). Overall percent agreement for the D-mannitol fermentation method was also lower (66.7%) than overall percent agreement for the 3 molecular assays (78.0%-80.2%). This study demonstrated, using a large, diverse group of Vibrio vulnificus isolates, that three assays could be used to distinguish most clinical vs environmental isolates; however, additional assays are needed to increase accuracy.


Subject(s)
Bacterial Proteins/genetics , Bacterial Typing Techniques , Vibrio Infections/diagnosis , Vibrio vulnificus/genetics , Vibrio vulnificus/pathogenicity , Animals , Bacterial Proteins/metabolism , Fermentation , Gene Expression , Humans , Mannitol/metabolism , RNA, Ribosomal, 16S/genetics , Seafood/microbiology , Shellfish/microbiology , United States , Vibrio Infections/microbiology , Vibrio Infections/pathology , Vibrio vulnificus/isolation & purification , Virulence , Water Microbiology
4.
BMC Public Health ; 19(1): 835, 2019 Jun 27.
Article in English | MEDLINE | ID: mdl-31248396

ABSTRACT

BACKGROUND: Commissioning and monitoring of community-based interventions is a challenge due to the complex nature of the environment and the lack of any explicit cut-offs to guide decision making. At what point, for example, is participant enrolment to interventions, course completion or satisfaction deemed to be acceptable or sufficient for continued funding? We aimed to identify and quantify key progression criteria for fourteen early years interventions by (1) agreeing the top three criteria for monitoring of successful implementation and progress; and (2) agreeing boundaries to categorise interventions as 'meeting anticipated target' (green); 'falling short of targets' (amber) and 'targets not being met' (red). METHODS: We ran three workshops in partnership with the UK's Big Lottery Fund commissioned programme 'Better Start Bradford' (implementing more than 20 interventions to improve the health, wellbeing and development of children aged 0-3) to support decision making by agreeing progression criteria for the interventions being delivered. Workshops included 72 participants, representing a range of professional groups including intervention delivery teams, commissioners, intervention-monitoring teams, academics and community representatives. After discussion and activities, final decisions were submitted using electronic voting devices. All participants were invited to reconsider their responses via a post-workshop questionnaire. RESULTS: Three key progression criteria were assigned to each of the 14 interventions. Overall, criteria that participants most commonly voted for were recruitment, implementation and reach, but these differed according to each intervention. Cut-off values used to indicate when an intervention moved to 'red' varied by criteria; the lowest being for recruitment, where participants agreed that meeting less than 65% of the targeted recruitment would be deemed as 'red' (falling short of target). CONCLUSIONS: Our methodology for monitoring the progression of interventions has resulted in a clear pathway which will support commissioners and intervention teams in local decision making within the Better Start Bradford programme and beyond. This work can support others wishing to implement a formal system for monitoring the progression of public health interventions.


Subject(s)
Child Health , Decision Making, Organizational , Health Promotion/organization & administration , Public Health Administration , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Pregnancy , Surveys and Questionnaires , United Kingdom
5.
Nanotechnology ; 29(45): 455703, 2018 Nov 09.
Article in English | MEDLINE | ID: mdl-30136652

ABSTRACT

Here, we report the synthesis and spectral properties of ultrathin nanodiscs (NDs) of Y2O3:Eu3+. It was found that the NDs of Y2O3:Eu3+ with a thickness of about 1 nm can be fabricated in a reproducible, facile and self-assembling process, which does not depend on the Eu3+ concentration. The thickness and morphology of these NDs were determined with small angle x-ray scattering and transmission electron microscopy. We found that the crystal field in these nanoparticles deviates from both the cubic and monoclinic characteristics, albeit the shape of the 5D0 â†’ 7F J (J = 0, 1, 2) transitions shows some similarity with the transitions in the monoclinic material. The Raman spectra of the non-annealed NDs manifest various vibration modes of the oleic acid molecules, which are used to stabilise the NDs. The annealed NDs show two very weak Raman lines, which may be assigned to vibrational modes of Y2O3 NDs. The concentration quenching of the Eu3+ luminescence of the NDs before annealing is largely suppressed and might be explained in terms of a reduction of the phonon density of states.

6.
Prev Sci ; 19(Suppl 1): 6-15, 2018 02.
Article in English | MEDLINE | ID: mdl-26830893

ABSTRACT

In a randomized controlled trial, we found that a cognitive behavioral program (CBP) was significantly more effective than usual care (UC) in preventing the onset of depressive episodes, although not everyone benefitted from the CBP intervention. The present paper explored this heterogeneity of response. Participants were 316 adolescents (M age = 14.8, SD = 1.4) at risk for depression due to having had a prior depressive episode or having current subsyndromal depressive symptoms and having a parent with a history of depression. Using a recursive partitioning approach to baseline characteristics, we (Weersing et al. 2016) previously had identified distinct risk clusters within conditions that predicted depressive episodes through the end of the continuation phase (month 9). The present study used the same risk clusters that had been derived in the CBP group through month 9 to reclassify the UC group and then to examine group differences in depression through month 33. We found that in this overall very high-risk sample, the CBP program was superior to UC among youth in the low-risk cluster (n = 33), characterized by higher functioning, lower anxiety, and parents not depressed at baseline, but not in the middle (n = 95) and high-risk (n = 25) clusters. Across conditions, significantly more depression-free days were found for youth in the low-risk cluster (M = 951.9, SD = 138.8) as compared to youth in the high-risk cluster (M = 800.5, SD = 226.7). Identification of moderators, based on purely prognostic indices, allows for more efficient use of resources and suggests possible prevention targets so as to increase the power of the intervention.


Subject(s)
Depression/prevention & control , Health Promotion , Adolescent , Female , Humans , Male , Outcome Assessment, Health Care , Patient Acceptance of Health Care , Randomized Controlled Trials as Topic , Risk Assessment
7.
Geohealth ; 1(9): 306-317, 2017 Nov.
Article in English | MEDLINE | ID: mdl-32158995

ABSTRACT

Incidences of harmful algal blooms (HABs) and Vibrio infections have increased over recent decades. Numerous studies have tried to identify environmental factors driving HABs and pathogenic Vibrio populations separately. Few have considered the two simultaneously, though emerging evidence suggests that algal blooms enhance Vibrio growth and survival. This study examined various physical, nutrient, and temporal factors associated with incidences of HABs, V. vulnificus, and V. parahaemolyticus in South Carolina coastal stormwater detention ponds, managed systems where HABs often proliferate, and their receiving tidal creek waters. Five blooms occurred during the study (2008-2009): two during relatively warmer months (an August 2008 cyanobacteria bloom and a November 2008 dinoflagellate bloom) followed by increases in both Vibrio species and V. parahaemolyticus, respectively, and three during cooler months (December 2008 through February 2009) caused by dinoflagellates and euglenophytes that were not associated with marked changes in Vibrio abundances. Vibrio concentrations were positively and significantly associated with temperature and dissolved organic matter, dinoflagellate blooms, negatively and significantly associated with suspended solids, but not significantly correlated with chlorophyll or nitrogen. While more research involving longer time series is needed to increase robustness, findings herein suggest that certain HAB species may augment Vibrio occurrences during warmer months.

8.
Neuropsychopharmacology ; 41(2): 598-610, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26108886

ABSTRACT

Schizophrenia patients exhibit deficits in signaling of the M1 subtype of muscarinic acetylcholine receptor (mAChR) in the prefrontal cortex (PFC) and also display impaired cortical long-term depression (LTD). We report that selective activation of the M1 mAChR subtype induces LTD in PFC and that this response is completely lost after repeated administration of phencyclidine (PCP), a mouse model of schizophrenia. Furthermore, discovery of a novel, systemically active M1 positive allosteric modulator (PAM), VU0453595, allowed us to evaluate the impact of selective potentiation of M1 on induction of LTD and behavioral deficits in PCP-treated mice. Interestingly, VU0453595 fully restored impaired LTD as well as deficits in cognitive function and social interaction in these mice. These results provide critical new insights into synaptic changes that may contribute to behavioral deficits in this mouse model and support a role for selective M1 PAMs as a novel approach for the treatment of schizophrenia.


Subject(s)
Antipsychotic Agents/pharmacology , Cognition/drug effects , Long-Term Synaptic Depression/drug effects , Pyridines/pharmacology , Pyrroles/pharmacology , Receptor, Muscarinic M1/metabolism , Schizophrenia/drug therapy , Animals , Cognition/physiology , Disease Models, Animal , Long-Term Synaptic Depression/physiology , Male , Mice, Inbred C57BL , Mice, Knockout , Patch-Clamp Techniques , Phencyclidine , Receptor, Muscarinic M1/genetics , Schizophrenia/physiopathology , Schizophrenic Psychology , Social Behavior
10.
BMJ Open ; 4(4): e004473, 2014 Apr 15.
Article in English | MEDLINE | ID: mdl-24736035

ABSTRACT

OBJECTIVE: To evaluate the process of implementation of the modified London Stroke Carers Training Course (LSCTC) in the Training Caregivers After Stroke (TRACS) cluster randomised trial and contribute to the interpretation of the TRACS trial results. The LSCTC was a structured competency-based training programme designed to help develop the knowledge and skills (eg, patient handling or transfer skills) essential for the day-to-day management of disabled survivors of stroke. The LSCTC comprised 14 components, 6 were mandatory (and delivered to all) and 8 non-mandatory, to be delivered based on individual assessment of caregiver need. DESIGN: Process evaluation using non-participant observation, documentary analysis and semistructured interviews. PARTICIPANTS: Patients with stroke (n=38), caregivers (n=38), stroke unit staff (n=53). SETTINGS: 10 of the 36 stroke units participating in the TRACS trial in four English regions (Yorkshire, North West, South East and South West, Peninsula). RESULTS: Preparatory cascade training on delivery of the LSCTC did not reach all staff and did not lead to multidisciplinary team (MDT) wide understanding of, engagement with or commitment to the LSCTC. Although senior therapists in most intervention units observed developed ownership of the LSCTC, MDT working led to separation rather than integration of delivery of LSCTC elements. Organisational features of stroke units and professionals' patient-focused practices limited the involvement of caregivers. Caregivers were often invited to observe therapy or care being provided by professionals but had few opportunities to make sense of, or to develop knowledge and stroke-specific skills provided by the LSCTC. Where provided, caregiver training came very late in the inpatient stay. Assessment and development of caregiver competence was not commonly observed. CONCLUSIONS: Contextual factors including service improvement pressures and staff perceptions of the necessity for and work required in caregiver training impacted negatively on implementation of the caregiver training intervention. Structured caregiver training programmes such as the LSCTC are unlikely to be practical in settings with short inpatient stays. Stroke units where early supported discharge is in place potentially offer a more effective vehicle for introducing competency based caregiver training. LINKED TRACS CLUSTER RANDOMISED CONTROLLED TRIAL NUMBER: ISRCTN49208824.


Subject(s)
Caregivers/education , Process Assessment, Health Care , Stroke Rehabilitation , Activities of Daily Living , Aged , England , Female , Humans , Interviews as Topic , Male , Middle Aged , Qualitative Research , Quality of Life
12.
Health Technol Assess ; 17(46): 1-216, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24153026

ABSTRACT

BACKGROUND: The majority of stroke patients are discharged home dependent on informal caregivers, usually family members, to provide assistance with activities of daily living (ADL), including bathing, dressing and toileting. Many caregivers feel unprepared for this role and this may have a detrimental effect on both the patient and caregiver. OBJECTIVE: To evaluate whether or not a structured, competency-based training programme for caregivers [the London Stroke Carer Training Course (LSCTC)] improved physical and psychological outcomes for patients and their caregivers after disabling stroke, and to determine if such a training programme is cost-effective. DESIGN: A pragmatic, multicentre, cluster randomised controlled trial. SETTING: Stratified randomisation of 36 stroke rehabilitation units (SRUs) to the intervention or control group by geographical region and quality of care. PARTICIPANTS: A total of 930 stroke patient and caregiver dyads were recruited. Patients were eligible if they had a confirmed diagnosis of stroke, were medically stable, were likely to return home with residual disability at the time of discharge and had a caregiver available, willing and able to provide support after discharge. The caregiver was defined as the main person--other than health, social or voluntary care provider--helping with ADL and/or advocating on behalf of the patient. INTERVENTION: The intervention (the LSCTC) comprised a number of caregiver training sessions and competency assessment delivered by SRU staff while the patient was in the SRU and one recommended follow-up session after discharge. The control group continued to provide usual care according to national guidelines. Recruitment was completed by independent researchers and participants were unaware of the SRUs' allocation. MAIN OUTCOME MEASURES: The primary outcomes were self-reported extended ADL for the patient and caregiver burden measured at 6 months after recruitment. Secondary outcomes included quality of life, mood and cost-effectiveness, with final follow-up at 12 months. RESULTS: No differences in primary outcomes were found between the groups at 6 months. Adjusted mean differences were -0.2 points [95% confidence interval (CI) -3.0 to 2.5 points; p = 0.866; intracluster correlation coefficient (ICC) = 0.027] for the patient Nottingham Extended Activities of Daily Living score and 0.5 points (95% CI -1.7 to 2.7 points; p = 0.660; ICC = 0.013) for the Caregiver Burden Scale. Furthermore, no differences were detected in any of the secondary outcomes. Intervention compliance varied across the units. Half of the participating centres had a compliance rating of > 60%. Analysis showed no evidence of higher levels of patient independence or lower levels of caregiver burden in the SRUs with better levels of intervention compliance. The economic evaluation suggests that from a patient and caregiver perspective, health and social care costs, societal costs and outcomes are similar for the intervention and control groups at 6 months, 12 months and over 1 year. CONCLUSIONS: We have conducted a robust multicentre, cluster randomised trial, demonstrating for the first time that this methodology is feasible in stroke rehabilitation research. There was no difference between the LSCTC and usual care with respect to improving stroke patients' recovery, reducing caregivers' burden, or improving other physical and psychological outcomes, nor was it cost-effective compared with usual care. Compliance with the intervention varied, but analysis indicated that a dose effect was unlikely. It is possible that the immediate post-stroke period may not be the ideal time for the delivery of structured training. The intervention approach might be more relevant if delivered after discharge by community-based teams. TRIAL REGISTRATION: Current Controlled Trials ISRCTN49208824. FUNDING: This project was funded by the MRC and is managed by the NIHR (project number 09/800/10) on behalf of the MRC-NIHR partnership, and will be published in full in Health Technology Assessment; Vol. 17, No. 46. See the NIHR Journals Library website for further project information.


Subject(s)
Caregivers/education , Caregivers/psychology , Inpatients , Patient Education as Topic/organization & administration , Stroke Rehabilitation , Activities of Daily Living , Affect , Aged , Aged, 80 and over , Cost-Benefit Analysis , Educational Status , Female , Health Behavior , Health Status , Humans , Male , Mental Health , Middle Aged , Moving and Lifting Patients/methods , Quality of Life , Quality-Adjusted Life Years , Self Care , Single-Blind Method
13.
Langmuir ; 28(11): 5295-301, 2012 Mar 20.
Article in English | MEDLINE | ID: mdl-22352851

ABSTRACT

The controlled electrophoretic deposition of monolayers and ultrathin films of 4.0 nm TiO(2) nanocrystals from stable, nonpolar solvent-based suspensions is reported. Stable suspensions were prepared in hexane, and the electrophoretic mobility of the nanocrystals was enhanced by a combination of a liquid-liquid extraction followed by mechanical surfactant removal by high-speed centrifugation. The controlled evolution of the density of TiO(2) nanocrystal monolayers was studied by transmission electron microscopy and optical transmittance spectroscopy. Ultrathin films were assembled while maintaining monolayer-by-monolayer growth and uniform density of the film. A time-dependent, equivalent circuit model has been proposed to characterize the electrophoretic current that was recorded during our experiments. Further, we demonstrate that the proposed model, coupled with the mobility, provides a means to estimate the deposition rate and, hence, the time necessary to fabricate a submonolayer, a monolayer, and multilayers of nanocrystals.

14.
Neuroscience ; 184: 164-71, 2011 Jun 16.
Article in English | MEDLINE | ID: mdl-21453757

ABSTRACT

Methamphetamine (MA) is an abused stimulant which can result in cognitive deficits and monoamine depletions. Animal models of neurotoxic MA exposure show reductions in dopamine, serotonin, and their associated transporters. MA abuse can result in long-term attention, working memory, and executive function deficits in humans and deficits in route-based egocentric learning, novel object recognition, and novel odor preference in rodents. MA has also been shown to affect brain-derived neurotrophic factor (BDNF) in humans and rodents. This experiment examined the effects of a MA binge dosing regimen (10 mg/kg x 4 at 2 h intervals, s.c.) in Sprague-Dawley rats on BDNF, tropomyosin receptor kinase B (TrkB), and tyrosine hydroxylase (TH) mRNA expression, and plasma corticosterone. Tissues were collected 1, 7, and 24 h following the last MA dose. Expression of BDNF and TrkB mRNA was analyzed using in situ hybridization with cRNA probes. Frontal, parietal, and entorhinal cortical BDNF mRNA expression were increased by MA exposure at all time-points. Increases in BDNF mRNA were also seen in the hippocampal CA1, prefrontal cortex (PFC), piriform cortex, and locus coeruleus but only at specific times. TrkB mRNA expression was modified in several subregions of the hippocampus as well as in PFC and striatum. TH mRNA was increased at the 1 h time-point in the substantia nigra pars compacta with no differences noted at the other times. Corticosterone levels were increased at all three time-points. The findings suggest that BDNF and its receptor may be upregulated as a compensatory mechanism after MA exposure.


Subject(s)
Brain-Derived Neurotrophic Factor/metabolism , Brain/drug effects , Methamphetamine/pharmacology , Receptor, trkB/metabolism , Animals , Brain/metabolism , Brain-Derived Neurotrophic Factor/genetics , Corticosterone/blood , Male , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Receptor, trkB/genetics
15.
Nanoscale Res Lett ; 5(10): 1540-5, 2010 Jun 20.
Article in English | MEDLINE | ID: mdl-21076671

ABSTRACT

The thermal relaxation of macrospins in a strongly interacting thin film of spinel-phase iron oxide nanocrystals (NCs) is probed by vibrating sample magnetometry (VSM). Thin films are fabricated by depositing FeO/Fe(3)O(4) core-shell NCs by electrophoretic deposition (EPD), followed by sintering at 400°C. Sintering transforms the core-shell structure to a uniform spinel phase, which effectively increases the magnetic moment per NC. Atomic force microscopy (AFM) confirms a large packing density and a reduced inter-particle separation in comparison with colloidal assemblies. At an applied field of 25 Oe, the superparamagnetic blocking temperature is T(B) (SP) ≈ 348 K, which is much larger than the Néel-Brown approximation of T(B) (SP) ≈ 210 K. The enhanced value of T(B) (SP) is attributed to strong dipole-dipole interactions and local exchange coupling between NCs. The field dependence of the blocking temperature, T(B) (SP)(H), is characterized by a monotonically decreasing function, which is in agreement with recent theoretical models of interacting macrospins.

16.
Nanotechnology ; 21(14): 145704, 2010 Apr 09.
Article in English | MEDLINE | ID: mdl-20220221

ABSTRACT

Eu(2)O(3) nanocrystals, surface-functionalized with oleic acid, were assembled into transparent thin films via electrophoretic deposition (EPD). Suspended in a non-polar solvent (hexane), the nanocrystals were cast into stable films on both the cathode and the anode. We characterized the nanocrystal films using optical microscopy, energy dispersive spectroscopy and photoluminescence spectroscopy. Scanning electron microscopy and atomic force microscopy provided information regarding the morphology, topology and surface coverage of the films. These homogeneous, densely packed films were composed predominantly of agglomerates (approximately 15 nm) of the Eu(2)O(3) nanocrystals rather than of individual nanocrystals. Nonetheless, the films possessed low root mean square (RMS) roughness (approximately 1.4 nm). High transparency of the film in the visible region was facilitated by the dense packing and the small diameter of the agglomerates, which reduced transmission losses due to scattering. The effect of EPD process parameters (applied voltage and nanocrystal concentration) on the growth uniformity and the thickness of the films was examined via surface contact profilometry. We discovered a correlation among the said EPD process parameters, the overall quality and thickness of these transparent films, which provided insight into the mechanisms of the nanocrystal deposition process.

17.
Neuroscience ; 163(1): 482-9, 2009 Sep 29.
Article in English | MEDLINE | ID: mdl-19505538

ABSTRACT

Decreased availability or efficacy of neurotrophic factors may underlie an increased susceptibility of mesencephalic dopaminergic cells to age-related degeneration. Neuregulins (NRGs) are pleotrophic growth factors for many cell types, including mesencephalic dopamine cells in culture and in vivo. The functional NRG receptor ErbB4 is expressed by virtually all midbrain dopamine neurons. To determine if levels of the NRG receptor are maintained during aging in the dopaminergic ventral mesencephalon, expression of ErbB4 mRNA and protein was examined in young (3 months), middle-aged (18 months), and old (24-25 months) Brown Norway/Fischer 344 F1 rats. ErbB4 mRNA levels in the substantia nigra pars compacta (SNpc), but not the adjacent ventral tegmental area (VTA) or subtantia nigra pars lateralis (SNl), were significantly reduced in the middle-aged and old animals when compared to young rats. Protein expression of ErbB4 in the ventral midbrain was significantly decreased in the old rats when compared to the young rats. Expression of tyrosine hydroxylase (TH) mRNA levels was significantly reduced in the old rats when compared to young animals in the SNpc, but not in the VTA or SNI. TH protein levels in the ventral midbrain were also decreased in the old animals when compared to the young animals. These data demonstrate a progressive decline of ErbB4 expression, coinciding with a loss of the dopamine-synthesizing enzyme TH, in the ventral midbrain of aged rats, particularly in the SNpc. These findings may implicate a role for diminished NRG/ErbB4 trophic support in dopamine-related neurodegenerative disorders of aging such as Parkinson's disease.


Subject(s)
Aging/metabolism , Dopamine/biosynthesis , ErbB Receptors/metabolism , Substantia Nigra/metabolism , Tyrosine 3-Monooxygenase/metabolism , Ventral Tegmental Area/metabolism , Aging/genetics , Animals , Cell Survival/genetics , Down-Regulation/genetics , ErbB Receptors/genetics , Gene Expression Regulation/physiology , Male , Nerve Degeneration/genetics , Nerve Degeneration/metabolism , Nerve Degeneration/physiopathology , Parkinson Disease/genetics , Parkinson Disease/metabolism , Parkinson Disease/physiopathology , RNA, Messenger/metabolism , Rats , Rats, Inbred F344 , Receptor, ErbB-4 , Substantia Nigra/cytology , Tyrosine 3-Monooxygenase/genetics , Ventral Tegmental Area/cytology
18.
Nanotechnology ; 19(19): 195301, 2008 May 14.
Article in English | MEDLINE | ID: mdl-21825710

ABSTRACT

Alternating layer, carbon nanotubes-nanocrystal composite films, comprising multi-walled carbon nanotubes (MWCNTs) and iron oxide (Fe(3)O(4)) nanocrystals, have been fabricated via electrophoretic deposition (EPD) on stainless steel and gold substrates. Low field-high current and high field-low current EPD schemes were integrated to produce the composite films. The low field-high current EPD approach produced porous mats from an aqueous suspension of the MWCNTs, while the high field-low current EPD approach produced tightly packed nanocrystal films from a dispersion of the nanocrystals in hexane. Large electric fields applied during the nanocrystal EPD and strong van der Waals interactions among the nanocrystals facilitated the formation of tightly packed nanocrystal films atop the MWCNT mats to create CNT mat-nanocrystal film composites. The surface coverage and homogeneity of the nanocrystal films improved with repeated deposition of the nanocrystals on the same mat. The assembly of nanotube mats on top of the CNT mat-nanocrystal film composite confirmed the feasibility of multilayered CNT mat-nanocrystal film heterostructures suitable for a range of devices. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques were employed to characterize the surface coverage, homogeneity, and topology of these composite films.

19.
Psychol Med ; 38(10): 1465-74, 2008 Oct.
Article in English | MEDLINE | ID: mdl-17976250

ABSTRACT

BACKGROUND: This study examined healthcare services used by adults diagnosed with an eating disorder (ED) in a large health maintenance organization in the Pacific Northwest. METHOD: Electronic medical records were used to collect information on all out-patient and in-patient visits and medication dispenses, from 2002 to 2004, for adults aged 18-55 years who received an ED diagnosis during 2003. Healthcare services received the year prior to, and following, the receipt of an ED diagnosis were examined. Cases were matched to five comparison health plan members who had a health plan visit close to the date of the matched case's ED diagnosis. RESULTS: Incidence of EDs (0.32% of the 104,130 females, and 0.02% of the 93,628 males) was consistent with prior research employing treatment-based databases, though less than community-based samples. Most cases (50%) were first identified during a primary-care visit and psychiatric co-morbidity was high. Health services use was significantly elevated in all service sectors among those with an ED when compared with matched controls both in the year preceding and that following the receipt of the incident ED diagnosis. Contrary to expectations, healthcare utilization was found to be similarly high across the spectrum of EDs (anorexia nervosa, bulimia nervosa, and eating disorders not otherwise specified). CONCLUSIONS: The elevation in health service use among women both before and after diagnosis suggests that EDs merit identification and treatment efforts commensurate with other mental health disorders (e.g. depression) which have similar healthcare impact.


Subject(s)
Feeding and Eating Disorders/therapy , Health Services/statistics & numerical data , Adolescent , Adult , Anxiety Disorders/epidemiology , Anxiety Disorders/therapy , Comorbidity , Depressive Disorder/epidemiology , Depressive Disorder/therapy , Feeding and Eating Disorders/epidemiology , Female , Humans , Male , Middle Aged , Northwestern United States/epidemiology , Office Visits/statistics & numerical data , Primary Health Care/statistics & numerical data , Stress Disorders, Post-Traumatic/epidemiology , Stress Disorders, Post-Traumatic/therapy
20.
J Environ Qual ; 36(6): 1661-9, 2007.
Article in English | MEDLINE | ID: mdl-17940266

ABSTRACT

A new library-based microbial source tracking (MST) approach intended for initial application in the coastal waters of Virginia was evaluated. Host-origin isolates of Enterococcus spp. were collected from beaches and the surrounding tidewater region of Virginia and used to construct a library based on the pattern of DNA band lengths produced by the amplification of the 16S-23S rDNA intergenic spacer (IGS) region, and subsequent digestion with MboI. Initial results from small host-origin libraries (64 and 200 total isolates) with discriminant analysis (DA) and logistic regression (LR) yielded high average rates of correct classification (ARCC) for a four-source classification split (birds, dogs, sewage, and wildlife), with ARCCs ranging from 83 to 100%. However, the poor results obtained when classification was attempted on a non-library validation set (VS, ARCCs of 47 and 48%, respectively, using DA and LR) demonstrated that a library of 200 isolates was insufficient to adequately represent the diversity of the enterococci in the sampled region. An increase in the library size to 1029 total isolates was accompanied by a reduction in the ARCC of the library to 42.7% with DA and 45.7% with LR, plus similarly poor results obtained from the VS. The low correct classification rates generated by the larger known-source library were unsuitable for field application. Many reported MST methods have been based on results obtained using small host-origin libraries without external validation. Our results indicate that such an approach can be very misleading, and that larger libraries and external validation is essential for the confirmation of preliminary results.


Subject(s)
DNA, Ribosomal/analysis , DNA, Ribosomal/genetics , Enterococcus/genetics , Animals , DNA, Ribosomal/classification , Enterococcus/classification , Enterococcus/isolation & purification , Feces/microbiology
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