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1.
J Appl Microbiol ; 130(5): 1481-1493, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33040472

RESUMO

AIMS: To evaluate the capacity of Lactobacillus hilgardii and Lactobacillus buchneri on modifying the bacterial community and improving fermentation and aerobic stability of high-moisture corn (HMC). METHODS AND RESULTS: High-moisture corn was untreated (CTR), treated with L. hilgardii (LH) or L. buchneri (LB) at 600 000 CFU per gram fresh weight, or with L. hilgardii and L. buchneri at 300 000 CFU per gram fresh weight each (LHLB), and stored for 10, 30 or 92 days. Compared to CTR, inoculated silages had higher Lactobacillaceae relative abundance, lower yeasts numbers and higher aerobic stability. Treatment with LHLB resulted in a higher acetic acid concentration than LH and higher 1,2 propanediol concentration than LB, such differences were numerically greater at 10 and 30 days but statistically greater at 92 days. At 10 days, all inoculated silages were more stable than CTR, but LHLB was even more stable than LB or LH. CONCLUSIONS: The combination of L. hilgardii and L. buchneri had a synergistic effect on yeast inhibition, leading to greater improvements in aerobic stability as early as 10 days after ensiling. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus hilgardii, especially in combination with L. buchneri, can improve the aerobic stability of HMC after a very short period of ensiling.


Assuntos
Lactobacillus/fisiologia , Microbiota , Silagem , Zea mays , Ácido Acético/análise , Aerobiose , Bactérias/crescimento & desenvolvimento , Fermentação , Propilenoglicol/análise , Silagem/análise , Silagem/microbiologia , Leveduras/crescimento & desenvolvimento , Zea mays/microbiologia
2.
J Dairy Sci ; 104(4): 4206-4222, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33612226

RESUMO

We determined if a microbial inoculant could improve the fermentation and aerobic stability of corn silage subjected to various challenges during storage that included an air stress challenge and low packing density. In Experiment 1, whole-plant corn was untreated (CTR) or treated (INO, Lactobacillus buchneri 40788 and Pediococcus pentosaceus 12455. Five individually replicated 7.5-L silos, at a density of 240 kg of dry matter (DM)/m3, for each treatment were kept sealed (NAS) for 19 wk, air stressed early (ES, 3 h/wk for wk 1-9), or air stressed late during storage (LS, 3 h/wk for wk 10-19). Inoculation increased the number of agar-culturable lactic acid bacteria regardless of air stress status, but it did not affect the relative abundance of Lactobacillus. Early, but not late air stress, resulted in silages with a higher relative abundance of Acetobacter when compared with NAS. Silages treated with INO had greater concentrations of acetic acid than CTR. Numbers of yeasts were lowest for INO regardless of air stress and CTR-LS had the most yeasts among all treatments. Silages that were not air stressed had a higher relative abundance of Candida tropicalis than air stressed silages. Monascus purpureus was detected in ES and LS but not in NAS, and its relative abundance was numerically higher in CTR-ES than in INO-ES and statistically higher in CTR-LS compared with INO-LS. Early air stress numerically reduced aerobic stability compared with NAS, and there was a statistical tendency for lower stability in LS compared with NAS. Inoculation improved aerobic stability regardless of when the air stress occurred. In Experiment 2, corn silage was prepared with the same primary treatments of CTR and INO but was packed at a low (LD; 180 kg of DM/m3) or a normal (ND; 240 kg of DM/m3) density and sealed (NAS) or air stressed (AS; 24 h on d 28, 42, and 89) for 92 d of storage. The concentration of acetic acid was greater in INO compared with CTR and in AS compared with NAS. Numbers of yeasts were lower in NAS compared with AS regardless of inoculation and they were lower in INO-AS compared with CTR-AS. Treatment with INO improved aerobic stability but the improvement was better in NAS versus AS and better in ND versus LD. Overall, our experiments corroborate past findings showing that INO markedly improves the aerobic stability of corn silage but they are the first to show that improvement can be sustained even when the silage was exposed to regular air stresses and when packed at a low density.


Assuntos
Silagem , Zea mays , Aerobiose , Animais , Fermentação , Lactobacillus , Silagem/análise
3.
Eur J Neurol ; 27(2): 215-220, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31610070

RESUMO

This paper describes 10 core features of a neuropsychological assessment with the aim of helping neurologists understand the unique contribution the evaluation can make within the wider context of diagnostic methods in epilepsy. The possibilities, limitations and cautions associated with the investigation are discussed under the following headings. (1) A neuropsychological assessment is a collaborative investigation. (2) Assessment prior to treatment allows for the accurate assessment of treatment effects. (3) The nature of an underlying lesion and its neurodevelopmental context play an important role in shaping the associated neuropsychological deficit. (4) Cognitive and behavioural impairments result from the essential comorbidities of epilepsy which can be considered as much a disorder of cognition and behaviour as of seizures. (5) Patients' subjective complaints can help us understand objective cognitive impairments and their underlying neuroanatomy, resulting in improved patient care. At other times, patient complaints reflect other factors and require careful interpretation. (6) The results from a neuropsychological assessment can be used to maximize the educational and occupational potentials of people with epilepsy. (7) Not all patients are able to engage with a neuropsychological assessment. (8) There are limitations in assessments conducted in a second language with tests that have been standardized on different populations from that of the patient. (9) Adequate intervals between assessments maximize sensitivity to meaningful change. (10) Patients should be fully informed about the purpose of the assessment and have realistic expectations of the outcome prior to referral.


Assuntos
Epilepsia/psicologia , Epilepsia/terapia , Neurologistas , Testes Neuropsicológicos , Humanos
4.
Clin Exp Immunol ; 190(1): 79-95, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28665482

RESUMO

Graft-versus-host disease (GVHD) remains a major problem after allogeneic haematopoietic stem cell transplantation, a curative therapy for haematological malignancies. Previous studies have demonstrated a role for the adenosine triphosphate (ATP)-gated P2X7 receptor channel in allogeneic mouse models of GVHD. In this study, injection of human peripheral blood mononuclear cells (PBMCs) into immunodeficient non-obese diabetic-severe combined immunodeficiency-interleukin (NOD-SCID-IL)-2Rγnull (NSG) mice established a humanized mouse model of GVHD. This model was used to study the effect of P2X7 blockade in this disease. From five weeks post-PBMC injection, humanized mice exhibited clinical signs and histopathology characteristic of GVHD. The P2X7 antagonist, Brilliant Blue G (BBG), blocked ATP-induced cation uptake into both murine and human cells in vitro. Injection of BBG (50 mg/kg) into NSG mice did not affect engraftment of human leucocytes (predominantly T cells), or the clinical score and survival of mice. In contrast, BBG injection reduced circulating human interferon (IFN)-γ significantly, which was produced by human CD4+ and CD8+ T cells. BBG also reduced human T cell infiltration and apoptosis in target organs of GVHD. In conclusion, the P2X7 antagonist BBG reduced circulating IFN-γ in a humanized mouse model of GVHD supporting a potential role for P2X7 to alter the pathology of this disease in humans.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Doença Enxerto-Hospedeiro/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas , Interferon gama/sangue , Antagonistas do Receptor Purinérgico P2X/uso terapêutico , Corantes de Rosanilina/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Doença Enxerto-Hospedeiro/imunologia , Humanos , Subunidade gama Comum de Receptores de Interleucina/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Receptores Purinérgicos P2X7/metabolismo , Transplante Homólogo
5.
Occup Med (Lond) ; 67(4): 296-300, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28339972

RESUMO

BACKGROUND: The growing prevalence of chronic conditions in the ageing workforce has been shown to have a negative impact in terms of optimal work performance and quality of life. It is therefore important to understand the factors associated with sickness absence due to health problems. AIMS: To examine the socio-demographics, health status indicators, barriers to self-care and social support associated with working adults missing work because of chronic conditions. METHODS: We analysed data from working adults in the USA with one or more chronic conditions who completed the National Council on Aging (NCOA) Chronic Care Survey. Analyses were performed using SPSS version 22; independent sample t-tests and chi-squared tests were used to compare sample characteristics and logistic regression was used to assess factors associated with missed work as a dichotomous outcome variable. RESULTS: Among the 250 study subjects, employees who reported poorer general health status [odd ratio (OR) = 1.62, P < 0.05], more physician visits (OR = 1.45, P < 0.01), not having enough money for their health (OR = 3.69, P < 0.01) and a higher reliance on their co-workers (OR = 1.71, P < 0.05) were significantly more likely to report sickness absence due to their chronic conditions. CONCLUSIONS: To reduce absences among employees with chronic conditions, employers need to understand the importance of factors such as employee income, resources and knowledge of disease self-care. US employers should explore opportunities for employees to offset health care costs, apply appropriate time-flexible work policies and encourage employees' participation in health knowledge enhancing interventions.


Assuntos
Doença Crônica/epidemiologia , Licença Médica/estatística & dados numéricos , Adulto , Idoso , Feminino , Nível de Saúde , Indicadores Básicos de Saúde , Humanos , Renda/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Autocuidado , Apoio Social , Estados Unidos/epidemiologia
6.
Am J Transplant ; 16(11): 3086-3092, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27172238

RESUMO

In this paper, we have reviewed the literature and report on kidney donors that are currently used at relatively low rates. Kidneys from donors with acute kidney injury (AKI) seem to have outcomes equivalent to those from donors without AKI, provided one can rule out significant cortical necrosis. Kidneys from donors with preexisting diabetes or hypertension may have marginally lower aggregate survival but still provide patients with a significant benefit over remaining on the wait list. The Kidney Donor Profile Index derives only an aggregate association with survival with a very modest C statistic; therefore, the data indicated that this index should not be the sole reason to discard a kidney, except perhaps in patients with extremely low estimated posttransplant survival scores. It is important to note that the Scientific Registry of Transplant Recipients models of risk adjustment should allay concerns regarding regulatory issues for observed outcomes falling below expectations. The successful utilization of kidneys from donation after cardiac death over the past decade shows how expanding our thinking can translate into more patients benefiting from transplantation. Given the growing number of patients on the wait list, broadening our approach to kidney acceptance could have an important impact on the population with end-stage renal disease. Many lives could be prolonged by carefully considering use of kidneys that are often discarded.


Assuntos
Seleção do Doador , Rim/fisiopatologia , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Cadáver , Humanos , Transplante de Rim
7.
Am J Transplant ; 16(3): 1015-20, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26689853

RESUMO

The aim of this study was to determine the clinical and histologic outcomes related to transplanting kidneys from deceased donors with glomerular fibrin thrombi (GFT). We included all cases transplanted between October 2003 and October 2014 that had either a preimplantation biopsy or an immediate postreperfusion biopsy showing GFT. The study cohort included 61 recipients (9.9%) with GFT and 557 in the control group without GFT. Delayed graft function occurred in 49% of the GFT group and 39% in the control group (p = 0.14). Serum creatinine at 1, 4, and 12 months and estimated GFR at 12 months were similar in the two groups. Estimated 1-year graft survival was 93.2% in the GFT group and 95.1% in the control group (p = 0.22 by log-rank). Fifty-two of the 61 patients in the GFT group (85%) had a 1-month protocol biopsy, and only two biopsies (4%) showed residual focal glomerular thrombi. At the 1-year protocol biopsy, the prevalence of moderate to severe interstitial fibrosis and tubular atrophy was 24% in the GFT group and 30% in the control group (p = 0.42). We concluded that GFT resolves rapidly after transplantation and that transplanting selected kidneys from deceased donors with GFT is a safe practice.


Assuntos
Fibrina/análise , Rejeição de Enxerto/prevenção & controle , Falência Renal Crônica/cirurgia , Glomérulos Renais/patologia , Transplante de Rim , Trombose/patologia , Doadores de Tecidos/provisão & distribuição , Adulto , Cadáver , Feminino , Seguimentos , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Humanos , Testes de Função Renal , Glomérulos Renais/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Trombose/metabolismo
8.
Am J Transplant ; 16(10): 2816-2835, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27273869

RESUMO

The Banff Working Group on Liver Allograft Pathology reviewed and discussed literature evidence regarding antibody-mediated liver allograft rejection at the 11th (Paris, France, June 5-10, 2011), 12th (Comandatuba, Brazil, August 19-23, 2013), and 13th (Vancouver, British Columbia, Canada, October 5-10, 2015) meetings of the Banff Conference on Allograft Pathology. Discussion continued online. The primary goal was to introduce guidelines and consensus criteria for the diagnosis of liver allograft antibody-mediated rejection and provide a comprehensive update of all Banff Schema recommendations. Included are new recommendations for complement component 4d tissue staining and interpretation, staging liver allograft fibrosis, and findings related to immunosuppression minimization. In an effort to create a single reference document, previous unchanged criteria are also included.


Assuntos
Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Isoanticorpos/imunologia , Transplante de Fígado/efeitos adversos , Aloenxertos , Humanos , Relatório de Pesquisa
9.
Am J Transplant ; 15(8): 2143-51, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25808278

RESUMO

Our aim was to determine outcomes with transplanting kidneys from deceased donors with acute kidney injury, defined as a donor with terminal serum creatinine ≥2.0 mg/dL, or a donor requiring acute renal replacement therapy. We included all patients who received deceased donor kidney transplant from June 2004 to October 2013. There were 162 AKI donor transplant recipients (21% of deceased donor transplants): 139 in the standard criteria donor (SCD) and 23 in the expanded criteria donor (ECD) cohort. 71% of the AKI donors had stage 3 (severe AKI), based on acute kidney injury network (AKIN) staging. Protocol biopsies were done at 1, 4, and 12 months posttransplant. One and four month formalin-fixed paraffin embedded (FFPE) biopsies from 48 patients (24 AKI donors, 24 non-AKI) underwent global gene expression profiling using DNA microarrays (96 arrays). DGF was more common in the AKI group but eGFR, graft survival at 1 year and proportion with IF/TA>2 at 1 year were similar for the two groups. At 1 month, there were 898 differentially expressed genes in the AKI group (p-value <0.005; FDR <10%), but by 4 months there were no differences. Transplanting selected kidneys from deceased donors with AKI is safe and has excellent outcomes.


Assuntos
Injúria Renal Aguda/fisiopatologia , Transplante de Rim , Doadores de Tecidos , Injúria Renal Aguda/genética , Adulto , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Chem Res Toxicol ; 28(10): 1975-86, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26382665

RESUMO

Many chemicals can induce skin sensitization, and there is a pressing need for non-animal methods to give a quantitative indication of potency. Using two large published data sets of skin sensitizers, we have allocated each sensitizing chemical to one of 10 mechanistic categories and then developed good QSAR models for the seven categories that have a sufficient number of chemicals to allow modeling. Both internal and external validation checks showed that each model had good predictivity.


Assuntos
Modelos Teóricos , Relação Quantitativa Estrutura-Atividade , Animais , Compostos Orgânicos/química , Compostos Orgânicos/toxicidade , Pele/efeitos dos fármacos , Pele/metabolismo
11.
Epilepsy Behav ; 51: 199-209, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26291774

RESUMO

Neurobehavioral and cognition problems are highly prevalent in epilepsy, but most research studies to date have not adequately addressed the precise nature of the relationship between these comorbidities and seizures. To address this complex issue and to facilitate collaborative, innovative research in the rising field of neurobehavioral comorbidities and cognition disturbances in new-onset epilepsy, international epilepsy experts met at the 3rd Halifax International Epilepsy Conference & Retreat at White Point, South Shore, Nova Scotia, Canada from September 18 to 20, 2014. This Conference Proceedings provides a summary of the conference proceedings. Specifically, the following topics are discussed: (i) role of comorbidities in epilepsy diagnosis and management, (ii) role of antiepileptic medications in understanding the relationship between epilepsy and neurobehavioral and cognition problems, and (iii) animal data and diagnostic approaches. Evidence to date, though limited, strongly suggests a bidirectional relationship between epilepsy and cognitive and psychiatric comorbidities. In fact, it is likely that seizures and neurobehavioral problems represent different symptoms of a common etiology or network-wide disturbance. As a reflection of this shared network, psychiatric comorbidities and/or cognition problems may actually precede the seizure occurrence and likely get often missed if not screened.


Assuntos
Transtornos Cognitivos/epidemiologia , Compreensão , Congressos como Assunto , Epilepsia/epidemiologia , Transtornos Mentais/epidemiologia , Animais , Canadá/epidemiologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/psicologia , Comorbidade , Epilepsia/diagnóstico , Epilepsia/psicologia , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/psicologia , Nova Escócia/epidemiologia
12.
J Dairy Sci ; 98(12): 8904-12, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26454298

RESUMO

The objective of this experiment was to evaluate the effect of a chemical additive on the fermentation and aerobic stability of high-moisture corn (HMC). Ground HMC (~63% dry matter) was untreated, or treated with an additive containing sodium benzoate, potassium sorbate, and sodium nitrite as active ingredients, at 0, 2, 3, or 4 L/t of fresh matter. Laboratory silos (7.5 L) were prepared and ensiled for 21 and 90d (4 silos/treatment per d of ensiling). Small bag silos were prepared for untreated HMC and HMC treated with 4 L/t of the additive and analyzed for nitrate-N and nitrite-N after 0, 3, and 7d of ensiling. The concentration of nitrate-N was similar between these 2 treatments and was below levels considered problematic for ruminants. Nitrite-N was greater in HMC treated with the high level of additive but was also very low for both treatments. Numbers of yeasts were similar among treatments in fresh HMC and decreased substantially after ensiling. Numbers of yeasts were similar among treatments after 21d of ensiling but after 90d they were lower in treated versus untreated HMC. Concentrations of organic acids (lactic, acetic, and propionic) and pH were not different among treatments at any time of ensiling. In contrast, treatment with the additive markedly decreased the concentration of ethanol in HMC after 21 and 90d when compared with untreated HMC. Treatment with all levels of the additive markedly improved the aerobic stability and improved the recovery of dry matter compared with untreated HMC. Overall, our findings suggest that the chemical additive used in this study has the potential to improve the fermentation and aerobic stability of HMC after a relatively short period (21d) and after a moderate length (90d) of ensiling.


Assuntos
Fermentação , Zea mays/química , Silagem/análise , Silagem/microbiologia , Benzoato de Sódio/análise , Nitrito de Sódio/análise , Ácido Sórbico/análise , Leveduras/isolamento & purificação , Zea mays/microbiologia
13.
Zoo Biol ; 34(1): 60-70, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25516334

RESUMO

In order to study the effect of concentrates restriction on feed consumption, diet digestibility, and utilization of nitrogen in captive Asian elephants (Elephas maximus), two feeding trials were conducted on three juveniles, four sub-adults, and three adults. During trial I, the conventional zoo diets of juveniles, sub-adults, and adult contained 22, 17, and 16% of concentrates on dry matter (DM) basis, respectively. During trial II, the amount of concentrate was reduced by 50%. A digestion trial of five days collection period was conducted during each period. The animals ate more roughages when concentrates were restricted. Intake of DM (g/kg BW(0.75) /day) was highest in sub-adults, followed by juveniles and adults. Apparent digestibility of crude protein (CP), neutral detergent soluble (NDS), and supply of digestible energy (DE) was highest in juveniles, followed by sub-adults and adults. Based upon the estimated metabolic fecal nitrogen (MFN) and calculated endogenous urinary nitrogen (EUN) and dermal losses, minimum dietary CP required to meet maintenance requirement was estimated to be 6.12, 6.05, and 5.97% in juveniles, sub-adults, and adults, respectively. Restriction of concentrates resulted in decreased (P < 0.05) digestibility of DM and GE, but the diet still supplied adequate amounts of DE and CP to fulfill estimated requirements of energy and protein during the period of experimentation. Thus, the concentrates portion of the diets of captive Asian elephants should be fed in a restricted way so as to reduce the intake of excessive calories and the potential risk of obesity.


Assuntos
Criação de Animais Domésticos/métodos , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais de Zoológico , Digestão/fisiologia , Ingestão de Alimentos/fisiologia , Elefantes/fisiologia , Alimentos Formulados , Nitrogênio/metabolismo , Fatores Etários , Animais , Nitrogênio/urina
14.
Br J Cancer ; 111(6): 1241-8, 2014 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-25117820

RESUMO

BACKGROUND: Bevacizumab has broad anti-tumour activity, but substantial risk of hypertension. No reliable markers are available for predicting bevacizumab-induced hypertension. METHODS: A genome-wide association study (GWAS) was performed in the phase III bevacizumab-based adjuvant breast cancer trial, ECOG-5103, to evaluate for an association between genotypes and hypertension. GWAS was conducted in those who had experienced systolic blood pressure (SBP) >160 mm Hg during therapy using binary analysis and a cumulative dose model for the total exposure of bevacizumab. Common toxicity criteria (CTC) grade 3-5 hypertension was also assessed. Candidate SNP validation was performed in the randomised phase III trial, ECOG-2100. RESULTS: When using the phenotype of SBP>160 mm Hg, the most significant association in SV2C (rs6453204) approached and met genome-wide significance in the binary model (P=6.0 × 10(-8); OR=3.3) and in the cumulative dose model (P=4.7 × 10(-8); HR=2.2), respectively. Similar associations with rs6453204 were seen for CTC grade 3-5 hypertension but did not meet genome-wide significance. Validation study from ECOG-2100 demonstrated a statistically significant association between this SNP and grade 3/4 hypertension using the binary model (P-value=0.037; OR=2.4). CONCLUSIONS: A genetic variant in SV2C predicted clinically relevant bevacizumab-induced hypertension in two independent, randomised phase III trials.


Assuntos
Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Hipertensão/induzido quimicamente , Hipertensão/genética , Glicoproteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Bevacizumab , Biomarcadores , Pressão Sanguínea , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único
15.
Soft Matter ; 10(9): 1329-36, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24651297

RESUMO

Autonomic materials are those that automatically respond to a change in environmental conditions, such as temperature or chemical composition. While such materials hold incredible potential for a wide range of uses, their implementation is limited by the small number of fully-developed material systems. To broaden the number of available systems, we have developed a post-functionalization technique where a reactive Ru catalyst ink is printed onto a non-responsive polymer substrate. Using a succinimide-amine coupling reaction, patterns are printed onto co-polymer or biomacromolecular films containing primary amine functionality, such as polyacrylamide (PAAm) or poly-N-isopropyl acrylamide (PNIPAAm) copolymerized with poly-N-(3-Aminopropyl)methacrylamide (PAPMAAm). When the films are placed in the Belousov-Zhabotinsky (BZ) solution medium, the reaction takes place only inside the printed nodes. In comparison to alternative BZ systems, where Ru-containing monomers are copolymerized with base monomers, reactive printing provides facile tuning of a range of hydrogel compositions, as well as enabling the formation of mechanically robust composite monoliths. The autonomic response of the printed nodes is similar for all matrices in the BZ solution concentrations examined, where the period of oscillation decreases in response to increasing sodium bromate or nitric acid concentration. A temperature increase reduces the period of oscillations and temperature gradients are shown to function as pace-makers, dictating the direction of the autonomic response (chemical waves).


Assuntos
Resinas Acrílicas/química , Hidrogéis/química , Polímeros/química , Acrilamidas/química , Impressão , Soluções , Temperatura
16.
Phys Rev Lett ; 110(24): 246803, 2013 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-25165953

RESUMO

We present an infrared transmission spectroscopy study of the inter-Landau-level excitations in quasineutral epitaxial graphene nanoribbon arrays. We observed a substantial deviation in energy of the L(0(-1)) → L(1(0)) transition from the characteristic square root magnetic-field dependence of two-dimensional graphene. This deviation arises from the formation of an upper-hybrid mode between the Landau-level transition and the plasmon resonance. In the quantum regime, the hybrid mode exhibits a distinct dispersion relation, markedly different from that expected for conventional two-dimensional systems and highly doped graphene.

18.
bioRxiv ; 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37745421

RESUMO

Genetic factors play a significant role in the risk for development of alcohol use disorder (AUD). Using 3-bottle choice intermittent access ethanol (IEA), we have employed the Diversity Outbred (DO) mouse panel as a model of alcohol use disorder in a genetically diverse population. Through use of gene expression network analysis techniques, in combination with expression quantitative trait loci (eQTL) mapping, we have completed an extensive analysis of the influence of genetic background on gene expression changes in the prefrontal cortex (PFC). This approach revealed that, in DO mice, genes whose expression was significantly disrupted by intermittent ethanol in the PFC also tended to be those whose expression correlated to intake. This finding is in contrast to previous studies of both mice and nonhuman primates. Importantly, these analyses identified genes involved in myelination in the PFC as significantly disrupted by IEA, correlated to ethanol intake, and having significant eQTLs. Genes that code for canonical components of the myelin sheath, such as Mbp, also emerged as key drivers of the gene expression response to intermittent ethanol drinking. Several regulators of myelination were also key drivers of gene expression, and had significant QTLs, indicating that genetic background may play an important role in regulation of brain myelination. These findings underscore the importance of disruption of normal myelination in the PFC in response to prolonged ethanol exposure, that genetic variation plays an important role in this response, and that this interaction between genetics and myelin disruption in the presence of ethanol may underlie previously observed behavioral changes under intermittent access ethanol drinking such as escalation of consumption.

19.
Appl Radiat Isot ; 201: 111027, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37748217

RESUMO

To fulfil the technical requirements for accreditation to ISO/IEC 17025, the end-to-end validation of all processes associated with standardising 60Co, including gravimetric source dispensing, primary standardisation by the 4π(LS)ß-γ coincidence and live-timed anti-coincidence extrapolation techniques, and impurity determination were performed and documented. Pure-beta-emitting impurities in a 60Co stock solution were identified. The impact of such impurities on measurement by liquid scintillation counting and comparison in the ESIR are discussed. A fresh 60Co source was produced, standardised, and compared using the SIR.

20.
Artigo em Inglês | MEDLINE | ID: mdl-22302526

RESUMO

Leaf-borne vibrations are potentially important to caterpillars for communication and risk assessment. Yet, little is known about the vibratory environment of caterpillars, or how they detect and discriminate between vibrations from relevant and non-relevant sources. We measured the vibratory 'landscape' of the territorial masked birch caterpillar Drepana arcuata (Drepanidae), and assessed its ability to detect and respond to vibrations generated by conspecific and predatory intruders, wind and rain. Residents of leaf shelters were shown to respond to low amplitude vibrations generated by a crawling conspecific intruder, since removal of the vibrations through leaf incision prevented the resident's response. Residents did not respond to large amplitude, low frequency disturbances caused by wind and rain alone, but did respond to approaching conspecifics under windy conditions, indicating an ability to discriminate between these sources. Residents also responded differently in the presence of vibrations generated by approaching predators (Podisus) and conspecifics. An analysis of vibration characteristics suggests that despite significant overlap between vibrations from different sources, there are differences in frequency and amplitude characteristics that caterpillars may use to discriminate between sources. Caterpillars live in a vibration-rich environment that we argue forms a prominent part of the sensory world of substrate bound holometabolous larvae.


Assuntos
Comunicação Animal , Comportamento Animal/fisiologia , Aprendizagem por Discriminação/fisiologia , Lepidópteros/fisiologia , Territorialidade , Tato/fisiologia , Animais , Vibração
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