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1.
J Chem Phys ; 155(20): 204201, 2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34852480

RESUMO

We perform two-dimensional Fourier transform spectroscopy on magneto-excitons in GaAs at magnetic fields and observe Zeeman splitting of the excitons. The Zeeman components are clearly resolved as separate peaks due to the two-dimensional nature of the spectra, leading to a more accurate measurement of the Zeeman splitting and the Landé g factors. Quantum coherent coupling between Zeeman components is observed using polarization dependent one-quantum two-dimensional spectroscopy. We use two-quantum two-dimensional spectroscopy to investigate higher four-particle correlations at high magnetic fields and reveal the role of the Zeeman splitting on the two-quantum transitions. The experimental two-dimensional spectra are simulated using the optical Bloch equations, where many-body effects are included phenomenologically.

2.
Cell Mol Life Sci ; 77(3): 395-413, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31768608

RESUMO

Microorganisms acquire energy and nutrients from dynamic environments, where substrates vary in both type and abundance. The regulatory system responsible for prioritizing preferred substrates is known as carbon catabolite repression (CCR). Two broad classes of CCR have been documented in the literature. The best described CCR strategy, referred to here as classic CCR (cCCR), has been experimentally and theoretically studied using model organisms such as Escherichia coli. cCCR phenotypes are often used to generalize universal strategies for fitness, sometimes incorrectly. For instance, extremely competitive microorganisms, such as Pseudomonads, which arguably have broader global distributions than E. coli, have achieved their success using metabolic strategies that are nearly opposite of cCCR. These organisms utilize a CCR strategy termed 'reverse CCR' (rCCR), because the order of preferred substrates is nearly reverse that of cCCR. rCCR phenotypes prefer organic acids over glucose, may or may not select preferred substrates to optimize growth rates, and do not allocate intracellular resources in a manner that produces an overflow metabolism. cCCR and rCCR have traditionally been interpreted from the perspective of monocultures, even though most microorganisms live in consortia. Here, we review the basic tenets of the two CCR strategies and consider these phenotypes from the perspective of resource acquisition in consortia, a scenario that surely influenced the evolution of cCCR and rCCR. For instance, cCCR and rCCR metabolism are near mirror images of each other; when considered from a consortium basis, the complementary properties of the two strategies can mitigate direct competition for energy and nutrients and instead establish cooperative division of labor.


Assuntos
Carbono/metabolismo , Repressão Catabólica/fisiologia , Pseudomonadaceae/metabolismo , Escherichia coli/metabolismo , Glucose/metabolismo , Humanos , Fenótipo
3.
Osteoporos Int ; 26(3): 891-910, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25510579

RESUMO

UNLABELLED: An international consensus process resulted in exercise and physical activity recommendations for individuals with osteoporosis. Emphasis was placed on strength, balance, and postural alignment. Rather than providing generic restrictions, activity should be encouraged while considering impairments, fracture risk, activity history, and preference, and guidance on spine sparing techniques should be provided. INTRODUCTION: The objectives of this study were to establish expert consensus on key questions posed by patients or health care providers regarding recommended assessment domains to inform exercise prescription, therapeutic goals of exercise, and physical activity and exercise recommendations for individuals with osteoporosis or osteoporotic vertebral fracture. METHODS: The Too Fit To Fracture expert panel identified researchers and clinicians with expertise in exercise and osteoporosis and stakeholder groups. We delivered a modified online Delphi survey (two rounds) to establish consensus on assessment, exercise, and physical activities for three cases with varying risk (osteoporosis based on bone mineral density; 1 spine fracture and osteoporosis; multiple spine fractures, osteoporosis, hyperkyphosis, and pain). Duplicate content analyses of free text responses were performed. RESULTS: Response rates were 52% (39/75) and 69% (48/70) for each round. Key consensus points are the following: (a) Current physical activity guidelines are appropriate for individuals with osteoporosis without spine fracture, but not for those with spine fracture; (b) after spine fracture, physical activity of moderate intensity is preferred to vigorous; (c) daily balance training and endurance training for spinal extensor muscles are recommended for all; (d) providing guidance on spine-sparing techniques (e.g., hip hinge) during activities of daily living or leisure, considering impairments, fracture risk, activity history, and preference, is recommended rather than providing generic restrictions (e.g., lifting <10 lbs, no twisting), but for those with vertebral fracture, especially in the presence of pain, multiple fractures, or hyperkyphosis, the risks of many activities may outweigh the benefits-physical therapist consultation is recommended. Examples of spine-sparing techniques and exercise prescription elements are provided. CONCLUSIONS: Our recommendations guide health care providers on assessment, exercise prescription, and safe movement for individuals with osteoporosis.


Assuntos
Terapia por Exercício/métodos , Atividade Motora/fisiologia , Osteoporose/reabilitação , Fraturas por Osteoporose/prevenção & controle , Fraturas da Coluna Vertebral/prevenção & controle , Acidentes por Quedas/prevenção & controle , Densidade Óssea/fisiologia , Técnica Delphi , Humanos , Osteoporose/diagnóstico , Osteoporose/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Postura/fisiologia , Guias de Prática Clínica como Assunto , Fraturas da Coluna Vertebral/fisiopatologia
4.
Gynecol Oncol ; 138(1): 55-61, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25895616

RESUMO

PURPOSE: Cediranib is a potent multitargeted inhibitor of vascular endothelial growth factor receptor (VEGFR) 1, 2 and 3. The study was initiated to evaluate the activity of cediranib in patients (pts) with recurrent ovarian, peritoneal or fallopian tube cancer (OC). METHODS: Eligible pts had persistent/recurrent OC following one prior platinum-based chemotherapy with measurable disease or progression based on Gynecologic Cancer Inter Group CA-125 criteria. Because of toxicities observed in the first 23 pts, the initial starting dose of oral daily (od) cediranib was reduced from 45mg to 30mg. The primary endpoint was objective response rate at 16weeks. This study was stratified into two arms: platinum-sensitive (PL-S) and platinum-resistant (PL-R). RESULTS: 74 pts were enrolled; 39 were PL-S and 35 PL-R, with a median age of 58years [31-87]. In PL-S group, 10 (26%) partial responses (PR) and 20 (51%) stable disease (SD) were confirmed while in the PL-R arm there were no confirmed PR and 23 pts (66%) had SD. The main grade 3/4 toxicities observed at the 30 mg starting dose were hypertension (27%), fatigue (20%) and diarrhea (14%). The median progression-free survival for all patients was 4.9months [3.9-7.0], 7.2months [4.3-9] for PL-S and 3.7months [2.6-4.5] for PL-R groups. The median overall survival was 18.9months (95% CI: 13.5-31.5); 27.7months [17.8-43.3] for PL-S and 11.9months [8.1-18.9] for PL-R groups. CONCLUSION: Cediranib shows significant activity in recurrent platinum sensitive OC. The toxicities were expected and manageable at the dose of 30mg od.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias das Tubas Uterinas/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Quinazolinas/administração & dosagem , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Quinazolinas/efeitos adversos
5.
Osteoporos Int ; 25(5): 1465-72, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24610579

RESUMO

UNLABELLED: An international consensus process identified the following research priorities in osteoporosis and exercise: study of exercise in high-risk cohorts, evaluation of multimodal interventions, research examining translation into practice and a goal to examine fracture outcomes. INTRODUCTION: To identify future research priorities related to exercise for people with osteoporosis with and without osteoporotic spine fracture via international consensus. METHODS: An international expert panel and representatives from Osteoporosis Canada led the process and identified opinion leaders or stakeholders to contribute. A focus group of four patient advocates identified quality of life, mobility, activities of daily living, falls, bone mineral density, and harms as outcomes important for decision-making. Seventy-five individuals were invited to participate in an online survey asking respondents to define future research priorities in the area of osteoporosis and exercise; the response rate was 57%. Fifty-five individuals from seven countries were invited to a half-day consensus meeting; 60% of invitees attended. The results of the online survey, knowledge synthesis activities, and results of the focus group were presented. Nominal group technique was used to come to consensus on research priorities. RESULTS: Research priorities included the study of exercise in high-risk cohorts (e.g., ≥ 65 years, low BMD, moderate/high risk of fracture, history of osteoporotic vertebral fractures, hyperkyphotic posture, functional impairments, or sedentary), the evaluation of multimodal interventions, research examining translation into practice, and a goal to examine fracture outcomes. The standardization of outcomes or protocols that could be evolved into large multicentre trials was discussed. CONCLUSIONS: The research priorities identified as part of the Too Fit To Fracture initiative can be used to inform the development of multicentre collaborations to evaluate and implement strategies for engaging individuals with osteoporosis in a safe and effective exercise.


Assuntos
Exercício Físico/fisiologia , Osteoporose/fisiopatologia , Fraturas por Osteoporose/prevenção & controle , Pesquisa Biomédica/métodos , Terapia por Exercício/métodos , Grupos Focais , Humanos , Fraturas por Osteoporose/fisiopatologia , Aptidão Física/fisiologia
6.
Osteoporos Int ; 25(3): 821-35, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24281053

RESUMO

SUMMARY: A consensus process was conducted to develop exercise recommendations for individuals with osteoporosis or vertebral fractures. A multicomponent exercise program that includes balance and resistance training is recommended. INTRODUCTION: The aim was to develop consensus on exercise recommendations for older adults: (1) with osteoporosis and (2) with osteoporotic vertebral fracture(s). METHODS: The Grading of Recommendations Assessment, Development, and Evaluation method was used to evaluate the quality of evidence and develop recommendations. Outcomes important for decision making were nominated by an expert panel and patient advocates. They included falls, fractures, bone mineral density (BMD), and adverse events for individuals with osteoporosis/vertebral fractures, and pain, quality of life, and function for those with vertebral fracture. Meta-analyses evaluating the effects of exercise on the outcomes were reviewed. Observational studies or clinical trials were reviewed when meta-analyses were not available. Quality ratings were generated, and informed the recommendations. RESULTS: The outcome for which evidence is strongest is falls. Point estimates of the effects of exercise on falls, fractures, and BMD vary according to exercise type. There is not enough evidence to quantify the risks of exercise in those with osteoporosis or vertebral fracture. Few trials of exercise exist in those with vertebral fracture. The exercise recommendations for exercise in individuals with osteoporosis or osteoporotic vertebral fracture are conditional. The panel strongly recommends a multicomponent exercise program including resistance and balance training for individuals with osteoporosis or osteoporotic vertebral fracture. The panel recommends that older adults with osteoporosis or vertebral fracture do not engage in aerobic training to the exclusion of resistance or balance training. CONCLUSIONS: The consensus of our international panel is that exercise is recommended for older adults with osteoporosis or vertebral fracture, but our recommendations are conditional.


Assuntos
Terapia por Exercício/métodos , Osteoporose/reabilitação , Fraturas por Osteoporose/reabilitação , Acidentes por Quedas/prevenção & controle , Atividades Cotidianas , Adulto , Idoso , Densidade Óssea/fisiologia , Medicina Baseada em Evidências/métodos , Humanos , Pessoa de Meia-Idade , Osteoporose/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Fraturas por Osteoporose/prevenção & controle , Equilíbrio Postural/fisiologia , Qualidade de Vida , Treinamento Resistido/métodos
7.
J Equine Vet Sci ; 141: 105165, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39154968

RESUMO

Indoor arenas do not always include mechanical ventilation or stirring fans and occupancy by horses and humans can be sporadic and inconsistent, which creates a challenging space for understanding and predicting variations in temperature, moisture, and airflow. To understand the interior environment within indoor arenas, monitoring was conducted at 15 facilities within 200 kilometres of Lexington, KY. Environmental monitoring of dry bulb temperature, relative humidity, dew point temperature, air speeds, and solar radiation took place over 7 days in the winter and summer to examine temporal variability. Environmental data was collected every 5 minutes using the HOBO RX3000 Remote Monitoring Station with the HOBOnet Temp/RH Sensor, HOBOnet Solar Radiation (Silicon Pyranometer) Sensor, and HOBOnet Ultrasonic Wind Speed and Direction Sensor. Clear seasonal differences and diurnal patterns were evident in all environmental conditions, but the relative humidity. The relative humidity and dew point temperatures indicated moisture could be an issue in many of the indoor arenas. High relative humidity and excess moisture can negatively impact horse and human health as well as the lifespan of the facility. Similar results to previous spatial variability indoor arena characterizations were observed during the environmental monitoring with air speeds being below the threshold for still air in livestock facilities (0.51 m s-1). Sensor technology and implementation provides a better understanding of the interior environment and how indoor arena design can impact it.


Assuntos
Abrigo para Animais , Animais , Cavalos , Estações do Ano , Temperatura , Monitoramento Ambiental/métodos , Umidade , Poluição do Ar em Ambientes Fechados/análise , Criação de Animais Domésticos/métodos
8.
J Chem Phys ; 138(20): 204716, 2013 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-23742509

RESUMO

We investigated the optical properties of 4,4'-stilbenedinitrene at low temperature and in high magnetic fields and compared the results with complementary first principles calculations. Both physical tuning parameters allow us to manipulate the singlet-triplet equilibrium, and by doing so, control the optical contrast (which is on the order of -2.5 × 10(2) cm(-1) at 555 nm and 35 T). Moreover, analysis of the magneto-optical response using a combined population and Beer's law framework reveals the singlet-triplet spin gap and identifies particular features in the absorption difference spectrum as deriving from singlet or triplet state excitations. These findings deepen our understanding of coupling in open shell molecules and show how chemical structure modification can modulate charge-spin interactions in organic biradicals.


Assuntos
Campos Magnéticos , Estilbenos/química , Estrutura Molecular , Temperatura
9.
Public Health Pract (Oxf) ; 5: 100351, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36567766

RESUMO

Objectives: To capture and compare the differences in experiences of public health Specialty Registrars who commenced training prior to the COVID-19 pandemic (pre-pandemic Registrars) and those who commenced training during the pandemic (post-pandemic Registrars). Study design: This is a mixed methods study comprising a cross-sectional survey and participatory action research. Methods: A questionnaire of 10 open and 5 closed questions exploring participants experience of training during the pandemic was sent to East Midlands Specialty Registrars. Thematic analysis and double coding were undertaken, coded based on pre- or post-pandemic Registrar status. Participatory action research was then undertaken in 2 rounds with 2 groups, based on pre/post-pandemic status to consolidate themes. Results: The survey was completed by 17 Registrars (8 pre-pandemic, and 9 post-pandemic) and 19 Registrars took part in participatory action research. The findings showed pre-pandemic Registrars noted the importance of negative impacts on their mental health whilst post-pandemic Registrars were more positive and felt well supported in their training. Conclusions: There is a stark difference in the impact of the pandemic for Registrars who started training before compared to during the pandemic. The training programme was not resilient to the impact of the pandemic. Robustness could be increased by encouraging early leadership experience and providing wellbeing support, particularly for post pandemic Registrars now and in future.

10.
BMJ Open Ophthalmol ; 8(Suppl 3): A2, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37797984

RESUMO

This feasibility study aimed to investigate the feasibility of collecting and analysing tear proteins from preterm infants at risk of retinopathy of prematurity (ROP). Additionally, we sought to identify any tear proteins which might be implicated in the pathophysiology of ROP.Eligible infants were those undergoing ROP screening without other ocular pathology. Tear samples were obtained by Schirmer's test strips coincident with routine ROP screening. Mass spectrometry was used for proteomic analysis. All participants' parents gave written, informed consent.Samples were collected from 12 infants, including two sets of twins. Gestation ranged from 25+6 to 31+1 weeks. Median postnatal age at sampling was 30.5 days (range 19 to 66). One infant developed self-limiting ROP. An adequate sample for protein analysis was obtained from each infant. 701 proteins were identified; 261 proteins identified in the majority of tear samples, including several common tear proteins, were used for analyses.Increased risk of ROP as determined by G-ROP prediction criteria was associated with an increase in lactate dehydrogenase B (LDH-B) chain protein in tears. Older, more mature infants demonstrated increased concentration of immunoglobulin complexes within their tear samples and two sets of twins in the cohort showed exceptionally similar proteomes, supporting validity of the analysis.Tear sampling by Schirmer test strips and subsequent proteomic analysis in preterm infants is feasible. A larger study is required to investigate the potential use of tear proteomics in early identification of ROP.


Assuntos
Recém-Nascido Prematuro , Retinopatia da Prematuridade , Lactente , Recém-Nascido , Humanos , Retinopatia da Prematuridade/diagnóstico , Proteômica , Idade Gestacional
11.
J Phys Condens Matter ; 35(30)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37075774

RESUMO

We use terahertz time-domain spectroscopy to study gallium arsenide two-dimensional electron gas samples in external magnetic field. We measure cyclotron decay as a function of temperature from 0.4 to10Kand a quantum confinement dependence of the cyclotron decay time belowT0=1.2K. In the wider quantum well, we observe a dramatic enhancement in the decay time due to the reduction in dephasing and the concomitant enhancement of superradiant decay in these systems. We show that the dephasing time in 2DEG's depends on both the scatteringrateand also on the distribution of scattering angles.

12.
J Proteomics ; 285: 104941, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37285906

RESUMO

There has been little information about the proteome of bovine faeces or about the contribution to the faecal proteome of proteins from the host, the feed or the intestinal microbiome. Here, the bovine faecal proteome and the origin of its component proteins was assessed, while also determining the effect of treating barley, the major carbohydrate in the feed, with either ammonia (ATB) or sodium propionate (PTB) preservative. Healthy continental crossbreed steers were allocated to two groups and fed on either of the barley-based diets. Five faecal samples from each group were collected on Day 81 of the trial and analysed by quantitative proteomics using nLC-ESI-MS/MS after tandem mass tag labelling. In total, 281 bovine proteins, 199 barley proteins, 176 bacterial proteins and 190 archaeal proteins were identified in the faeces. Mucosal pentraxin, albumin and digestive enzymes were among bovine proteins identified. Serpin Z4 a protease inhibitor was the most abundant barley protein identified which is also found in barley-based beer, while numerous microbial proteins were identified, many originating bacteria from Clostridium, while Methanobrevibacter was the dominant archaeal genus. Thirty-nine proteins were differentially abundant between groups, the majority being more abundant in the PTB group compared to the ATB group. SIGNIFICANCE: Proteomic examination of faeces is becoming a valuable means to assess the health of the gastro-intestinal tract in several species, but knowledge on the proteins present in bovine faeces is limited. This investigation aimed to characterise the proteome of bovine faecal extracts in order to evaluate the potential for investigations of the proteome as a means to assess the health, disease and welfare of cattle in the future. The investigation was able to identify proteins in bovine faeces that had been (i) produced by the individual cattle, (ii) present in the barley-based feed eaten by the cattle or (iii) produced by bacteria and other microbes in the rumen or intestines. Bovine proteins identified included mucosal pentraxin, serum albumin and a variety of digestive enzymes. Barley proteins found in the faeces included serpin Z4, a protease inhibitor that is also found in beer having survived the brewing process. Bacterial and archaeal proteins in the faecal extracts were related to several pathways related to the metabolism of carbohydrates. The recognition of the range of proteins that can be identified in bovine faeces raises the possibility that non-invasive sample collection of this material could provide a novel diagnostic approach to cattle health and welfare.


Assuntos
Proteínas Arqueais , Hordeum , Serpinas , Bovinos , Animais , Serpinas/análise , Proteoma/análise , Cerveja/análise , Proteômica , Espectrometria de Massas em Tandem , Dieta/veterinária , Fezes/microbiologia , Bactérias , Extratos Vegetais , Ração Animal/análise
14.
J Chem Phys ; 135(24): 241101, 2011 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-22225135

RESUMO

We investigated the tunability of the singlet-triplet equilibrium population in the organic biradical 1,4-phenylenedinitrene via magneto-optical spectroscopy. A rich magnetochromic response occurs because applied field increases the concentration of the triplet state species, which has a unique optical signature by comparison with the singlet biradical and the precursor molecule. A Curie-like analysis of the magneto-optical properties allows us to extract the spin gap, which is smaller than previously supposed. These measurements establish the value of local-probe photophysical techniques for magnetic property determination in open-shell systems such as biradicals where a traditional electron paramagnetic resonance Curie law analysis has intrinsic limitations.

15.
Sci Rep ; 11(1): 1457, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446818

RESUMO

Pseudomonas aeruginosa is a globally-distributed bacterium often found in medical infections. The opportunistic pathogen uses a different, carbon catabolite repression (CCR) strategy than many, model microorganisms. It does not utilize a classic diauxie phenotype, nor does it follow common systems biology assumptions including preferential consumption of glucose with an 'overflow' metabolism. Despite these contradictions, P. aeruginosa is competitive in many, disparate environments underscoring knowledge gaps in microbial ecology and systems biology. Physiological, omics, and in silico analyses were used to quantify the P. aeruginosa CCR strategy known as 'reverse diauxie'. An ecological basis of reverse diauxie was identified using a genome-scale, metabolic model interrogated with in vitro omics data. Reverse diauxie preference for lower energy, nonfermentable carbon sources, such as acetate or succinate over glucose, was predicted using a multidimensional strategy which minimized resource investment into central metabolism while completely oxidizing substrates. Application of a common, in silico optimization criterion, which maximizes growth rate, did not predict the reverse diauxie phenotypes. This study quantifies P. aeruginosa metabolic strategies foundational to its wide distribution and virulence including its potentially, mutualistic interactions with microorganisms found commonly in the environment and in medical infections.


Assuntos
Proteínas de Bactérias/metabolismo , Modelos Biológicos , Pseudomonas aeruginosa/metabolismo , Humanos , Pseudomonas aeruginosa/patogenicidade
16.
IBRO Rep ; 9: 290-301, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33204893

RESUMO

This study investigated the impact of a brief meditation workshop on a sample of 223 novice meditators. Participants attended a three-day workshop comprising daily guided seated meditation sessions using music without vocals that focused on various emotional states and intentions (open focus). Based on the theory of integrative consciousness, it was hypothesized that altered states of consciousness would be experienced by participants during the meditation intervention as assessed using electroencephalogram (EEG). Brainwave power bands patterns were measured throughout the meditation training workshop, producing a total of 5616 EEG scans. Changes in conscious states were analysed using pre-meditation and post-meditation session measures of delta through to gamma oscillations. Results suggested the meditation intervention had large varying effects on EEG spectra (up to 50 % increase and 24 % decrease), and the speed of change from pre-meditation to post-meditation state of the EEG co-spectra was significant (with 0.76 probability of entering end-meditation state within the first minute). There was a main 5 % decrease in delta power (95 % HDI = [-0.07, -0.03]); a global increase in theta power of 29 % (95 % HDI = [0.27, 0.33]); a global increase of 16 % (95 % HDI = [0.13, 0.19]) in alpha power; a main effect of condition, with global beta power increasing by 17 % (95 % HDI = [0.15, 0.19]); and an 11 % increase (95 % HDI = [0.08, 0.14]) in gamma power from pre-meditation to end-meditation. Findings provided preliminary support for brief meditation in altering states of consciousness in novice meditators. Future clinical examination of meditation was recommended as an intervention for mental health conditions particularly associated with hippocampal impairments.

17.
Phys Rev Lett ; 103(26): 267402, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-20366345

RESUMO

We measured the low-lying crystal field levels of Nd3+ in Nd3Ga5SiO14 via magneto-optical spectroscopy and employed the extracted energies, magnetic moments, and symmetries to analyze the magnetic properties and test the spin liquid candidacy of this material. The exchange interaction is surprisingly small, a discovery that places severe constraints on models used to describe the ground state of this system. Further, it demonstrates the value of local-probe photophysical techniques for rare-earth-containing materials where bulk property measurements can be skewed by low-lying electronic structure.

18.
Science ; 260(5105): 171-6, 1993 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-17807175

RESUMO

The Landers earthquake, which had a moment magnitude (M(w)) of 7.3, was the largest earthquake to strike the contiguous United States in 40 years. This earthquake resulted from the rupture of five major and many minor right-lateral faults near the southern end of the eastern California shear zone, just north of the San Andreas fault. Its M(w) 6.1 preshock and M(w) 6.2 aftershock had their own aftershocks and foreshocks. Surficial geological observations are consistent with local and far-field seismologic observations of the earthquake. Large surficial offsets (as great as 6 meters) and a relatively short rupture length (85 kilometers) are consistent with seismological calculations of a high stress drop (200 bars), which is in turn consistent with an apparently long recurrence interval for these faults.

19.
Diabetes Obes Metab ; 11(10): 913-30, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19531058

RESUMO

AIM: It is estimated that more than 180 million people worldwide have diabetes. Health-care providers can remotely deliver health services to this patient population using information and communication technology, also known as home telehealth. Home telehealth may be classified into two subtypes: home telemonitoring (HTM) and telephone support (TS). The research objective was to systematically review the literature and perform meta-analyses to assess the potential benefits of home telehealth compared with usual care (UC) for patients with diabetes. METHODS: An electronic literature search was conducted to identify studies on home telehealth and patients with diabetes that were published between 1998 and 2008 using Medline, Medline In-Process & Other Non-Indexed Citations, BIOSIS Previews and EMBASE. RESULTS: Twenty-six studies (n = 5069 patients) on home telehealth for diabetes were selected. Twenty-one studies evaluated HTM and 5 randomized controlled trials assessed TS. HTM had a positive effect on glycaemic control [as measured by lower glycated haemoglobin level] compared with UC (weighted mean difference =-0.21; 95% confidence interval -0.35 to -0.08), but the results were mixed for TS. Study results indicated that home telehealth helps to reduce the number of patients hospitalized, hospitalizations and bed days of care. Home telehealth was similar or favourable to UC across studies for quality-of-life and patient satisfaction outcomes. CONCLUSIONS: In general, home telehealth had a positive impact on the use of numerous health services and glycaemic control. More studies of higher methodological quality are required to give more precise insights into the potential clinical effectiveness of home telehealth interventions.


Assuntos
Diabetes Mellitus/terapia , Serviços de Assistência Domiciliar/normas , Telemedicina/normas , Serviços de Assistência Domiciliar/organização & administração , Humanos , Avaliação de Resultados em Cuidados de Saúde , Satisfação do Paciente , Qualidade de Vida , Telemedicina/métodos , Telemedicina/estatística & dados numéricos
20.
Med Mycol ; 47(6): 625-39, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19306217

RESUMO

A retrospective study of cryptococcosis in domestic animals residing in Western Australia was conducted over an 11-year-period (from 1995 to 2006) by searching the data base of Murdoch University Veterinary Teaching hospital and the largest private clinical pathology laboratory in Perth. Cryptococcosis was identified in 155 animals: 72 cats, 57 dogs, 20 horses, three alpacas, two ferrets and a sheep. There was no seasonal trend apparent from the dates of diagnosis. Taking into account the commonness of accessions to Murdoch University, cats were five to six times more likely to develop this disease than dogs, and three times more likely than horses, while horses were almost twice as likely as dogs to become infected. Amongst the feline cohort, Ragdoll and Birman breeds were over-represented, while in dogs several pedigree breeds were similarly overrepresented. Dogs and horses tended to develop disease at an early age (one to five years), while cats were presented over a much wider range of ages. In cats and dogs the upper respiratory tract was the most common primary site of infection, while horses and alpacas tended to have lower respiratory involvement. The most striking finding of the study was the high frequency with which C. gattii was identified, with infections attributable to this species comprising 5/9 cats, 11/22 dogs, 9/9 horses and 1/1 alpaca, where appropriate testing was conducted. Preliminary molecular genotyping suggested that most of the C. gattii infections in domestic animals (9/9 cases) were of the VGII genotype. This contrasts the situation on the eastern seaboard of Australia, where disease attributable to C. gattii is less common and mainly due to the VGI genotype. C. gattii therefore appears to be an important cause of cryptococcosis in Western Australia.


Assuntos
Gatos/microbiologia , Criptococose , Cryptococcus gattii/genética , Cryptococcus neoformans/genética , Cães/microbiologia , Animais , Antifúngicos/uso terapêutico , Camelídeos Americanos/microbiologia , Criptococose/tratamento farmacológico , Criptococose/epidemiologia , Criptococose/microbiologia , Criptococose/veterinária , Cryptococcus gattii/isolamento & purificação , Cryptococcus neoformans/isolamento & purificação , Genótipo , Cavalos/microbiologia , Hospitais Veterinários , Hospitais de Ensino , Prevalência , Estudos Retrospectivos
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