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Beef-calf mortality rates across tropical and subtropical Australia are high, with sub-optimal nutrition in pregnant cows being the primary risk. The nutritional deficiencies associated with calf mortality are the same as those associated with reduced milk yields. Although the highest mortality risk occurs during neonatal life, the role of inadequate milk delivery to beef neonates is not well established. This study investigated the frequency of low milk delivery in tropically adapted neonatal calves and the time for their dams to initiate full lactation in five management groups of Brahman and Droughtmaster calving cows in the dry tropics of northern Queensland, Australia. Change in calf weight in the days following birth was the primary measure of milk uptake. Plasma globulin concentration was used to indicate colostrum uptake. Across management groups, data were available on 250 calves for regression analysis of average daily gain vs. globulin and on 78 for plotting calf growth profiles. Calves had one of two growth profiles, either with immediate high growth from birth (day one) or with high growth delayed until day three. The frequency of delayed growth calves (with inadequate milk intake to gain at least 0.5 kg by day three after birth) was on average 30% across management groups, with management groups ranging 25%-50%. The frequency of calves growing ≤0.2 kg/day to day three was 15%-37%, depending on management group. The frequency of calves growing ≤0.2 kg/day to day five was 7%-20%, depending on management group. Calf globulin explained only 25% of the variation in calf average daily gain. Our study shows that a third of tropically adapted calves may experience a three-day delay to initiation of full lactation by their dams. Although study conditions were relatively benign, any additional risks with milk delivery, such as those that occur widely in tropical and subtropical northern Australia, would place such calves at risk of dehydration and mortality. Calf plasma globulin should not be used as a standalone measure of adequacy of neonatal milk delivery, especially when comparing across herds. This study demonstrates a fundamental problem of high frequency in northern Australia. The underlying risks for delayed milk delivery should be considered in the quest for practical solutions to reduce tropically adapted beef-calf mortalities.
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Ração Animal , Leite , Ração Animal/análise , Animais , Bovinos , Colostro , Feminino , Lactação , Parto , GravidezRESUMO
We study transport mediated by Andreev bound states formed in InSb nanowire quantum dots. Two kinds of superconducting source and drain contacts are used: epitaxial Al/InSb devices exhibit a doubling of tunneling resonances, while, in NbTiN/InSb devices, Andreev spectra of the dot appear to be replicated multiple times at increasing source-drain bias voltages. In both devices, a mirage of a crowded spectrum is created. To describe the observations a model is developed that combines the effects of a soft induced gap and of additional Andreev bound states both in the quantum dot and in the finite regions of the nanowire adjacent to the quantum dot. Understanding of Andreev spectroscopy is important for the correct interpretation of Majorana experiments done on the same structures.
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The aim of this study was to evaluate the use of real-time polymerase chain reaction (qPCR) combined with DNA extraction directly from composite milk and bulk tank samples for detection and enumeration of Streptococcus agalactiae (SAG) causing subclinical mastitis. Dilutions of sterile reconstituted skim milk inoculated with SAG ATCC 13813 were used to establish a standard curve (cfu/mL) for the qPCR assay targeting SAG. The analytical sensitivity and repeatability of the qPCR assay were determined. Bulk tank (BTM; n = 38) and composite milk samples (CM; n = 26) collected from lactating cows with positive isolation of SAG were submitted to the qPCR protocol and SAG plate counting, with results from both methods compared. Amplification of DNA was not possible in two out of 64 samples, indicating that qPCR was able to detect SAG in 96 and 97% of BTM and CM samples, respectively. The inter-assay coefficient of variation was <5%, showing that the technique had adequate repeatability. The qPCR protocol can be a high-throughput and rapid diagnostic assay to accurately detect SAG from BTM and CM samples compared with conventional microbiological culture method. However, the evaluated qPCR protocol is not accurate for enumerating SAG in milk samples, probably due to quantification of DNA of non-viable cells.
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Carga Bacteriana/métodos , Leite/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Streptococcus agalactiae/isolamento & purificação , Animais , Infecções Assintomáticas , Bovinos , Mastite Bovina/microbiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Streptococcus agalactiae/genéticaRESUMO
Coagulase-negative staphylococci (CoNS) are among the main pathogens causing bovine intramammary infection (IMI) in many countries. However, one of the limitations related to the specific diagnosis of CoNS is the lack of an accurate, rapid, and convenient method that can differentiate the bacterial species comprising this group. The aim of this study was to evaluate the ability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to accurately identify CoNS species in dairy cow IMI. In addition, the study aimed to determine the frequency of CoNS species causing bovine IMI. A total of 108 bacterial isolates were diagnosed as CoNS by microbiological cultures from two milk samples collected from 21 dairy herds; the first sample was collected at the cow level (i.e., 1,242 composite samples from all quarters), while the second sample was collected at the mammary quarter level (i.e., 1,140 mammary samples collected from 285 cows). After CoNS isolation was confirmed by microbiological culture for both samples, all CoNS isolates (n=108) were genotypically differentiated by PCR restriction fragment length polymorphism (RFLP) analysis of a partial groEL gene sequence and subjected to the MALDI-TOF MS identification procedure. MALDI-TOF MS correctly identified 103 (95.4%) of the CoNS isolates identified by PCR-RFLP at the species level. Eleven CoNS species isolated from bovine IMI were identified by PCR-RFLP, and the most prevalent species was Staphylococcus chromogenes (n=80; 74.1%). In conclusion, MALDI-TOF MS may be a reliable alternative method for differentiating CoNS species causing bovine IMI.
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Doenças dos Bovinos/microbiologia , Coagulase/genética , Mastite Bovina/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Infecções Estafilocócicas/microbiologia , Staphylococcus/genética , Animais , Bovinos , Feminino , Leite/microbiologiaRESUMO
Resveratrol, a modulator of several signaling proteins, can exert off-target effects involving the peroxisome proliferator-activated receptor (PPAR) transcription factors. However, evidence for the direct interaction between this polyphenol and PPARs is lacking. Here, we addressed the hypothesis that resveratrol and its metabolites control aspects of PPAR transcriptional activity through direct interaction with PPARs. Bioaffinity chromatographic studies with the immobilized ligand-binding domains (LBDs) of PPARγ and PPARα and isothermal titration calorimetry allowed the binding affinities of resveratrol, resveratrol 3-O-glucuronide, resveratrol 4-O-glucuronide, and resveratrol 3-O-sulfate to both PPAR-LBDs to be determined. Interaction of resveratrol, resveratrol 3-O-glucuronide, and resveratrol 4-O-glucuronide with PPARγ-LBD occurred with binding affinities of 1.4, 1.1, and 0.8 µM, respectively, although only resveratrol bound to the PPARα-LBD with a binding affinity of 2.7 µM. Subsequently, X-ray crystallographic studies were carried out to characterize resveratrol binding to the PPARγ-LBD at the molecular level. The electron density map from the crystal structure of the complex between PPARγ-LBD and resveratrol revealed the presence of one molecule of resveratrol bound to the LBD of PPARγ, with the ligand occupying a position close to that of other known PPARγ ligands. Transactivation assays were also performed in HepG2 cells, with the results showing that resveratrol was not a PPAR agonist but instead was able to displace rosiglitazone from PPARγ and Wy-14643 from PPARα with IC50 values of (27.4±1.8) µM and (31.7±2.5) µM, respectively. We propose that resveratrol acts as a PPAR antagonist through its direct interaction with PPARγ and PPARα.
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Receptores Ativados por Proliferador de Peroxissomo/antagonistas & inibidores , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Estilbenos/metabolismo , Estilbenos/farmacologia , Sítios de Ligação , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Modelos Moleculares , Receptores Ativados por Proliferador de Peroxissomo/química , Pirimidinas/farmacologia , Resveratrol , Rosiglitazona , Relação Estrutura-Atividade , Tiazolidinedionas/farmacologia , Células Tumorais CultivadasRESUMO
Hyponatremia is the most common electrolyte disturbance in hospitalized children, with a reported incidence of 15-30%, but its overall incidence and severity are not well known. The objective of our study was to determine the incidence, severity, and associated risk factors of community- and hospital-acquired hyponatremia on a general pediatric ward. Data of 5550 children admitted from June 2012 to December 2019 on plasma sodium and discharge diagnosis were analyzed by logistic regression model. Clinically relevant diagnostic groups were created. Hyponatremia was classified as mild, moderate, and severe. The incidence of community- and hospital-acquired hyponatremia was 15.8% and 1.4%, respectively. Most of the cases were mild (90.8%) to moderate (8.6%), with only two cases of severe community-acquired hyponatremia. There were no clinical complications in any of the hyponatremic children. Age and diagnosis at discharge were principal factors significantly correlated with hyponatremia. Community-acquired hyponatremia is more common than hospital-acquired hyponatremia in clinical practice. Severe cases of both types are rare. Children from 2 to 11 years of age presenting with infections, cardiovascular disorders, and gastrointestinal disorders are at risk of developing hyponatremia.
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Graphene nanoribbons can be folded into a double layer system keeping the two layers decoupled. In the quantum Hall regime folds behave as a new type of Hall bar edge. We show that the symmetry properties of the zero Landau level in metallic nanoribbons dictate that the zero energy edge states traversing a fold are perfectly transmitted onto the opposite layer. This result is valid irrespective of fold geometry, magnetic field strength, and crystallographic orientation of the nanoribbon. Backscattering suppression on the N=0 Hall plateau is ultimately due to the orthogonality of forward and backward channels, much like in the Klein paradox.
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Molecular targeted therapy of advanced neuroendocrine tumours (NETs) of the gastroenteropancreatic (GEP) system currently encompasses approved therapy with the mammalian target of rapamycin (mTOR) inhibitor everolimus and the multi-tyrosinkinase inhibitor sunitinib. However, clinical efficacy of these treatment strategies is limited by low objective response rates and limited progression-free survival due to tumour resistance. Further novel strategies for molecular targeted therapy of NETs of the GEP system are needed. This paper reviews preclinical research models and signalling pathways in NETs of the GEP system. Preclinical and early clinical data on putative novel targets for molecular targeted therapy of NETs of the GEP system are discussed, including PI3K, Akt, mTORC1/mTORC2, GSK3, c-Met, Ras-Raf-MEK-ERK, embryogenic pathways (Hedgehog, Notch, Wnt/beta-catenin, TGF-beta signalling and SMAD proteins), tumour suppressors and cell cycle regulators (p53, cyclin-dependent kinases (CDKs) CDK4/6, CDK inhibitor p27, retinoblastoma protein (Rb)), heat shock protein HSP90, Aurora kinase, Src kinase family, focal adhesion kinase and epigenetic modulation by histone deacetylase inhibitors.
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BACKGROUND: This research was undertaken to evaluate Oxford Domed Lateral unicompartmental knee replacement (UKR) survival and clinical and radiological outcomes. The study also considered the influence of body mass index (BMI) on results and proposed contralateral healthy knee anatomic femorotibial angle (AFTA) as a predictor of postoperative knee alignment. METHODS: A retrospective evaluation of 41 primary Oxford Domed Lateral UKR performed in 41 patients in the same institution was undertaken on a patient group comprising of 10 men and 31 women with a mean age of 63â¯years (range: 38-81â¯years). A minimum follow-up of two years was required. RESULTS: The total revision rate was one out of 41 patients (2.4%), with a mean follow-up of 49â¯months (range: 25-84â¯months). One patient presented with a traumatic medial dislocation of the bearing after 15â¯months (resulting in an overall dislocation rate of 2.4%). The visual analogue scale (VAS) and the Oxford knee score (OKS) demonstrated significant postoperative improvement (Pâ¯<â¯0.001). Survival at five years, with revision for any reason as the endpoint, was 97.5%. No significant correlation was observed between BMI and postoperative flexion angle, radiologically measured parameters, or pre- and postoperative VAS and OKS. Significant correlation was found (râ¯=â¯0.77, Pâ¯<â¯0.001) between postoperative and contralateral healthy knee anatomic femorotibial angles. CONCLUSIONS: The Oxford Domed Lateral UKR presents a low dislocation rate and excellent mid-term clinical and functional results. Contralateral healthy knee AFTA appears to be a predictor of postoperative knee alignment.
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Artroplastia do Joelho/instrumentação , Artroplastia do Joelho/métodos , Prótese do Joelho , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia , Avaliação de Resultados da Assistência ao Paciente , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Escala Visual AnalógicaRESUMO
Arteriovenous malformations (AVM) in the scalp are infrequent vascular lesions. Its clinical presentation varies from annoying and unaesthetic mass of the skin to devastating hemorrhages. Its origin can be congenital or traumatic. The diagnosis of AVM is based on physical examination and confirmed by internal and external carotid angiography. Nowadays the gold standard treatment is the surgical intervention although the endovascular approach is gaining field in order to reduce blood losses as presurgical or like lonely treatment. A 50 year old woman was admitted with a huge mass in scalp, with subcutaneous enlarged vessels and no other symptoms. A head traumatic antecedent had occurred 12 years before. The angiography evidenced a mottled AVM with blood supplies from the external and internal carotid arteries, with meningeal transosseous branches from both ophthalmic arteries. Endovascular treatment could not be performed due to high risk of uni or bilateral amaurosis. Thus, a conventional surgical treatment was done without complications. The treatment of AVM of scalp offers various possibilities but the individualization of each case becomes essential to decide the correct management in order to avoid complications.
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Malformações Arteriovenosas , Couro Cabeludo , Malformações Arteriovenosas/diagnóstico , Malformações Arteriovenosas/patologia , Malformações Arteriovenosas/cirurgia , Angiografia Cerebral , Feminino , Humanos , Pessoa de Meia-Idade , Couro Cabeludo/anormalidades , Couro Cabeludo/irrigação sanguínea , Couro Cabeludo/cirurgiaRESUMO
This research aimed to evaluate the effects of the beta-agonist zilpaterol hydrochloride (ZH) on carcass traits, subprimal yield, meat quality, palatability traits, and gene expression in Nellore heifers. Zilpaterol increased Longissimus lumborum area and did not change back fat thickness, meat color, and cooking loss. Heifers fed ZH had greater hindquarter weight and carcass percentage. Muscles from hindquarter were heavier for animals fed ZH. Forequarter (% of carcass) decreased and brisket did not change with ZH supplementation. There were no differences between treatments for steak aroma, beef flavor, and off-flavor. However, tenderness and juiciness were reduced by ZH, depending on postmortem aging. Zilpaterol increased Calpain-1, Calpain-2, and calpastatin mRNA expression, with no effect of day of slaughter or ZH×Day interaction. In conclusion, ZH supplementation improved hypertrophy, meat production, and debone yield in Nellore heifers, which led to decreased tenderness and to increased mRNA expression in the calpain-calpastatin system.
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Proteínas de Ligação ao Cálcio/metabolismo , Calpaína/metabolismo , Carne Vermelha , Compostos de Trimetilsilil/farmacologia , Animais , Proteínas de Ligação ao Cálcio/genética , Calpaína/genética , Bovinos , Cor , Comportamento do Consumidor , Culinária , Aditivos Alimentares/farmacologia , Qualidade dos Alimentos , Expressão Gênica , Humanos , Concentração de Íons de Hidrogênio , RNA Mensageiro , PaladarRESUMO
Major improvements have been achieved in endovascular treatment of intracranial aneurysms during the last twenty years. Initial techniques of selective balloon occlusion were progressively replaced by the packing of the aneurysmal pouch with very small and soft metallic devices, named coils, with controlled detachment. In some rare cases, balloon occlusion is still used in order to occlude the parent vessel or to reverse the flow, especially in the vertebro-basilar system. Essential aims for the anaesthesiologist include: complete immobility of the patient throughout the endovascular procedure, systemic anticoagulation in order to avoid any thromboembolic complication during and after treatment, prevention and/or treatment of vasospasm, precise evaluation of fluid balance during the procedure. Our experience is based on 145 aneurysms in 135 patients, treated by endovascular route; 91 (63%) of them were revealed by a subarachnoid haemorrhage (SAH). Their main locations were: the carotid siphon (33.1%), the anterior communicating artery (19.3%), the basilar artery (17.2%) and the middle cerebral artery (17.2%). Thirty-seven of these aneurysms (25.5%) were very small in size with a diameter less than 4 mm. Total or sub-total (more than 90%) occlusion was achieved in 141 aneurysms (90.3%). Thromboembolic complications occurred in eight patients (5.9%), neurological sequelae in one. Other treatment-related complications included the migration of a coil outside the aneurysm in six cases (4.4%) without neurological deficit in one and five ruptures of the aneurysm (3.7%) during the procedure with one lethal issue due to the spontaneous bleeding of a controlateral arterio-venous malformation. Thirteen patients died (9.6%). The cause of the death was related on the initial SAH in 11 of them. The two others were both due to rupture: of a second untreated aneurysm in one case and of an associated arteriovenous malformation in the second one. At present the main indications of endovascular treatment are poor or non indications for neurosurgery. Due to the quality of results, endovascular therapy will be more and more used in case of ruptured or non ruptured aneurysms.
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Embolização Terapêutica/métodos , Aneurisma Intracraniano/terapia , Radiologia Intervencionista , Stents , Angiografia Cerebral , Embolização Terapêutica/efeitos adversos , HumanosRESUMO
Sperm cryopreservation is widely used for both research and reproduction purposes, but its effect on sperm DNA damage remains controversial. Sperm DNA fragmentation (SDF) has become an important biomarker to assess male infertility. In particular, the differentiation between single- and double-stranded DNA fragmentation (ssSDF and dsSDF) has clinical implications for male infertility where ssSDF is associated with reduced fertility, whereas dsSDF is associated with increased risk of miscarriage. In this study, semen samples from 30 human males have been analysed in both fresh and cryopreserved using the alkaline and neutral Comet assays. Results show an increase of about 10% of ssSDF, assessed by the alkaline Comet assay, regardless of the male fertility status. Neutral Comet analysis of dsSDF does not show any statistical increase when comparing fresh and cryopreserved samples in any of the patient groups. Results support previous reports that oxidative stress is the major effector in DNA damage during sample cryopreservation, as, on one hand, ssSDF has previously been related to oxidative damage and, on the other hand, we have not found any effect on dsSDF. Therefore, there might be a slight risk of decreased fertility after using a freezed sample, but no evidence for increased miscarriage risk from cryopreserved spermatozoa should be expected.
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Criopreservação , Fragmentação do DNA , Preservação do Sêmen/efeitos adversos , Espermatozoides/citologia , Ensaio Cometa , Humanos , Infertilidade Masculina , Masculino , Estresse Oxidativo , Sêmen , Análise do SêmenRESUMO
Sperm DNA fragmentation (SDF) is becoming an important test to assess male infertility. Several different tests are available, but no consensus has yet been reached as to which tests are most predictive of infertility. Few publications have reported a comprehensive analysis comparing these methods within the same population. The objective of this study was to analyze the differences between the five most common methodologies, to study their correlations and to establish their cut-off values, sensitivity and specificity in predicting male infertility. We found differences in SDF between fertile donors and infertile patients in TUNEL, SCSA, SCD and alkaline Comet assays, but none with the neutral Comet assay. The alkaline COMET assay was the best in predicting male infertility followed by TUNEL, SCD and SCSA, whereas the neutral COMET assay had no predictive power. For our patient population, threshold values for infertility were 20.05% for TUNEL assay, 18.90% for SCSA, 22.75% for the SCD test, 45.37% for alkaline Comet and 34.37% for neutral Comet. This work establishes in a comprehensive study that the all techniques except neutral Comet are useful to distinguish fertile and infertile men.
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Fragmentação do DNA , Infertilidade Masculina/diagnóstico , Análise do Sêmen/métodos , Espermatozoides/citologia , Cromatina/metabolismo , Ensaio Cometa , Humanos , Marcação In Situ das Extremidades Cortadas , Infertilidade Masculina/genética , MasculinoRESUMO
The peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptor superfamily. In the last years novel PPARs ligands have been identified and these include PPARα/γ dual agonists. To rapidly identify novel PPARs dual ligands, a robust binding assay amenable to high-throughput screening toward PPAR isoforms would be desirable. In this work we describe a parallel assay based on the principles of frontal affinity chromatography coupled to mass spectrometry (FAC-MS) that can be used to characterize dual agonists. For this purpose the ligand binding domain of PPARα receptor was immobilized onto the surface of open tubular capillaries to create new PPAR-alpha-OT columns to be used in parallel with PPAR-gamma-OT columns. The two biochromatographic systems were used in both ranking and Kd experiments toward new ureidofibrate-like dual agonists for subtype selectivity ratio determination. In order to validate the system, the Kd values determined by frontal analysis chromatography were compared to the affinity constants obtained by ITC experiments. The results of this study strongly demonstrate the specific nature of the interaction of the ligands with the two immobilized receptor subtypes.
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Cromatografia de Afinidade/instrumentação , Cromatografia de Afinidade/métodos , Espectrometria de Massas/métodos , PPAR alfa/química , PPAR gama/química , Calorimetria , Descoberta de Drogas/métodos , Proteínas Imobilizadas/agonistas , Proteínas Imobilizadas/química , Proteínas Imobilizadas/metabolismo , Ligantes , PPAR alfa/agonistas , PPAR alfa/metabolismo , PPAR gama/agonistas , PPAR gama/metabolismo , Ligação Proteica , Reprodutibilidade dos TestesRESUMO
The present study aimed to evaluate non-fiber carbohydrates (NFC) in sugarcane-based diets on rumen pH, and forage digestibility, and to describe NFC degradation curves. The study consisted of two trials. For the first trial, three rumen cannulated steers, BW of 350 ± 15 kg (mean ± SE), were assigned in a 3×3 Latin Square (LS) design. They were fed diets containing finely-ground (0.9 mm average particle size) corn (GC), steam-rolled corn (SRC), or pelleted citrus pulp (PCP). Each period had 14 d, with the first 12 for adaptation. The 13th d was for serial measurement of rumen pH, and the14th for rumen fluid collection and in vitro incubation for DM and NDF digestibility (IVDMD and IVNDFD) of bermudagrass hay (Hay), corn (CS), and sugarcane (SS) silages. In the second trial, rumen fluid of a cannulated bull, fed corn silage and a regular concentrate, was collected for in vitro digestion of NFC for multiple time points. The incubation results were used to adjust the NFC degradation curves, and calculate lag-time, feed fractions, and degradation rate. Data from first trial was analyzed in a 3×3 LS. The model for the digestibility parameters included fixed effects of forage (Feed), diets with NFC (Diet), and their interaction (Feed × Diet), and random effect of animal and period. The model for rumen pH included fixed effect of diet, time as repeated measures, animal and period as random effects. The significance was considered at probability ≤ 5% (α = 0.05). The NFC degradation curves were adjusted using the PROC NLIN procedure from SAS, and equation parameters compared using confidence intervals. There was a Diet × Time interaction on rumen pH (P = 0.04), where SRC decreased pH compared to PCP and GC diets at the time 6 h, only. There was no Feed × Diet interaction effect (P > 0.05) for any digestibility parameter. There was a Feed effect on both IVDMD and IVNDFD, either after 30 or 48 h incubation (P < 0.01). The CS had the greatest IVDMD, followed by SS and Hay, after 30 and 48 h of incubation. The CS had the greatest IVNDFD after 30 h, compared to SS and Hay. However, for IVNDFD after 48 h, CS presented the greatest mean, followed by SS and Hay. The rumen fluid from animals fed SRC decreased both IVDMD and IVNDFD (P < 0.05) of all roughages after 48 h. Results from the second trial showed that the PCP had lower Lag Time, B fraction and greater kd compared to both corn sources, and SRC had greater kd than GC. In conclusion, the SRC diet decreased rumen pH 6 h after feeding and, consequently, decreased fiber digestibility of the tropical forage sources evaluated. Although the PCP had lower lag time, and faster rate of degradation of B fraction, it did not negatively affect rumen pH or fiber digestibility of forage.(AU)
O presente estudo teve como objetivo avaliar os carboidratos não-fibrosos (CNF) em dietas à base de cana-de-açúcar sobre o pH ruminal e digestibilidade da forragem, e descrever as curvas de degradação dos CNF. O estudo foi composto de dois ensaios. No primeiro, três novilhos canulados no rúmen, com peso vivo de 350 ± 15 kg (Média ± DP), foram alocados em um quadrado latino (QL) 3×3, e alimentados com dietas contendo: milho moído (MM, tamanho de partículas 0,9 mm), laminado a vapor (MLV) ou polpa cítrica peletizada (PCP). Cada período tinha 14 d, sendo os primeiros 12 para adaptação e o 13º para a medição seriada do pH e o 14º para a coleta de líquido ruminal e incubação in vitro para digestibilidade da MS e FDN (DIVMS e DIVFDN) de feno de bermudagrass (Feno) e silagens de milho (SM) e cana (SC). No segundo ensaio, coletou-se fluido ruminal de um touro canulado, alimentado com silagem de milho e concentrado padrão, para digestão in vitro dos CNF em vários tempos. Esses resultados foram utilizados para ajustar as curvas de degradação dos CNF e calcular o tempo de colonização, frações alimentares e taxa de degradação. Os resultados do primeiro ensaio foram analisados em um QL 3×3. O modelo dos parâmetros de digestibilidade incluiu efeito fixo de forragem (Alimento), dieta com CNF (Dieta) e interação (Alimento × Dieta), e efeito aleatório de animal e período. O modelo para pH incluiu efeito fixo de Dieta, Tempo como medida repetida, animal e período como aleatórios. Foi considerada a probabilidade significativa de ≤ 5% (α = 0,05). As curvas de degradação dos CNF foram ajustadas pelo PROC NLIN do SAS, e parâmetros de equação comparados por intervalo de confiança. Houve interação Dieta × Tempo no pH ruminal (P = 0,04), onde o MLV diminuiu o pH comparado com PCP e MM apenas no tempo 6 h. Não houve interação Alimento × Dieta (P > 0,05) para nenhum parâmetro de digestibilidade. Houve efeito de Alimento sobre a DIVMS e DIVFDN, após 30 e 48 h de incubação (P < 0,01). A SM teve a maior DIVMS, seguido por SC e Feno, após 30 e 48 h de incubação. A SM teve a maior DIVFDN após 30 h, comparado com SC e Feno. No entanto, para DIVFDN após 48 h, a SM teve maior média, seguida da SC e Feno. O fluido ruminal de animais alimentados com MLV diminuiu a DIVMS e DIVFDN (P < 0.05) de todas as forragens, após 48 h. Resultados do segundo ensaio mostram que PCP diminuiu o tempo de colonização, fração B e aumentou a kd comparado com os dois milhos, e MLV apresentou maior kd que o MM. Em conclusão, a dieta com MLV diminuiu o pH ruminal no tempo 6 h e, consequentemente, diminuiu a DIVFDN das forragens avaliadas. Embora PCP tenha apresentado menor tempo de colonização e maior taxa de degradação da fração B, não afetou negativamente o pH do rúmen nem a digestibilidade da fibra das forragens. (au)
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Carboidratos/análise , Citrus/química , Ruminação Digestiva , Zea mays/efeitos adversosAssuntos
Análise Química do Sangue/normas , Ensaio de Proficiência Laboratorial/organização & administração , Garantia da Qualidade dos Cuidados de Saúde/normas , Sociedades Científicas/normas , Urinálise/normas , Comitês Consultivos , Consenso , Humanos , Ensaio de Proficiência Laboratorial/normas , Guias de Prática Clínica como Assunto , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Controle de Qualidade , EspanhaRESUMO
We propose a nonmagnetic, pseudospin-based version of a spin valve, in which the pseudospin polarization in neighboring regions of a graphene bilayer is controlled by external gates. Numerical calculations demonstrate a large on-off ratio of such a device. This finding holds promise for the realization of pseudospintronics: a form of electronics based upon the manipulation of pseudospin analogous to the control of physical spin in spintronics applications.
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O artigo aborda o significado que toma o termo fé no campo da psicanálise, tal como introduzido por Bion no contexto de seu pensamento a partir do livro Transformações. Para penetrar a penumbra de significados do termo, a autora se dirige à concepção religiosa de fé, usando subsídios do pensamento de Søren Kierkegaard. O artigo procede a uma aproximação dos dois vértices numa ilustração clínica do conceito de fé.
This paper explores the meaning of faith in the field of psychoanalysis, as introduced by Bion in the context of his thoughts since 1965, in his book Tansformations. The author searches the religious concept of faith in the thoughts of Søren Kierkegaard and tries to approximate the two vertices through a clinical illustration of the concept of faith.