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1.
bioRxiv ; 2023 Mar 24.
Article in English | MEDLINE | ID: mdl-36993629

ABSTRACT

Neural circuit function is shaped both by the cell types that comprise the circuit and the connections between those cell types 1 . Neural cell types have previously been defined by morphology 2, 3 , electrophysiology 4, 5 , transcriptomic expression 6-8 , connectivity 9-13 , or even a combination of such modalities 14-16 . More recently, the Patch-seq technique has enabled the characterization of morphology (M), electrophysiology (E), and transcriptomic (T) properties from individual cells 17-20 . Using this technique, these properties were integrated to define 28, inhibitory multimodal, MET-types in mouse primary visual cortex 21 . It is unknown how these MET-types connect within the broader cortical circuitry however. Here we show that we can predict the MET-type identity of inhibitory cells within a large-scale electron microscopy (EM) dataset and these MET-types have distinct ultrastructural features and synapse connectivity patterns. We found that EM Martinotti cells, a well defined morphological cell type 22, 23 known to be Somatostatin positive (Sst+) 24, 25 , were successfully predicted to belong to Sst+ MET-types. Each identified MET-type had distinct axon myelination patterns and synapsed onto specific excitatory targets. Our results demonstrate that morphological features can be used to link cell type identities across imaging modalities, which enables further comparison of connectivity in relation to transcriptomic or electrophysiological properties. Furthermore, our results show that MET-types have distinct connectivity patterns, supporting the use of MET-types and connectivity to meaningfully define cell types.

2.
Sci Rep ; 11(1): 981, 2021 01 13.
Article in English | MEDLINE | ID: mdl-33441691

ABSTRACT

Esophageal cancer (EC) is an aggressive disease, presenting two main histological subtypes: adenocarcinoma (EAC) and squamous cell carcinoma (ESCC). The two EC subtypes widely differ concerning virtually all factors. ESCC development is mainly associated with tobacco and alcohol abuse, whereas obesity and chronic gastroesophageal reflux disease (GERD) are important risk factors not only for EAC, but also for for Barrett's esophagus (BE), an intestinal metaplasia that precedes EAC. Obesity triggers ectopic lipid droplets (LD) accumulation in non-adipose tissues. LD are organelles involved in cell metabolism, signaling, proliferation and production of inflammatory mediators. Therefore, the aim of this work was to investigate LD occurrence and role in EC. This study shows progressive LD levels increase along EAC development, in esophageal samples from non-obese through obese individuals, as well as BE, and EAC patients, whereas no significant changes were observed in ESCC samples, when compared to non-tumor samples. Additionally, in order to mimic BE and EAC risk factors exposure, a non-tumor esophageal cell line was incubated with oleic acid (OA) and acidified medium and/or deoxycholic acid (DCA), revealing a significant increment in LD amount as well as in COX-2 and CXCL-8 expression, and in IL-8 secretion. Further, COX-2 expression and LD amount presented a significant positive correlation and were detected co-localized in EAC, but not in ESCC, suggesting that LD may be the site for eicosanoid production in EAC. In conclusion, this study shows that obesity, and BE- and EAC-associated inflammatory stimuli result in a gradual increase of LD, that may be responsible for orchestrating inflammatory mediators' production and/or action, thus contributing to BE and EAC genesis and progression.


Subject(s)
Adenocarcinoma/metabolism , Barrett Esophagus/metabolism , Cyclooxygenase 2/metabolism , Esophageal Neoplasms/metabolism , Esophageal Squamous Cell Carcinoma/metabolism , Lipid Droplets/metabolism , Signal Transduction/physiology , Adenocarcinoma/pathology , Barrett Esophagus/pathology , Cell Line , Esophageal Neoplasms/pathology , Esophageal Squamous Cell Carcinoma/pathology , Esophagus/metabolism , Esophagus/pathology , Gastroesophageal Reflux/metabolism , Gastroesophageal Reflux/pathology , Humans , Inflammation/metabolism , Inflammation/pathology , Risk Factors
3.
ISME J ; 14(12): 3011-3023, 2020 12.
Article in English | MEDLINE | ID: mdl-32770118

ABSTRACT

Lakes play a pivotal role in ecological and biogeochemical processes and have been described as "sentinels" of environmental change. Assessing "lake health" across large geographic scales is critical to predict the stability of their ecosystem services and their vulnerability to anthropogenic disturbances. The LakePulse research network is tasked with the assessment of lake health across gradients of land use on a continental scale. Bacterial communities are an integral and rapidly responding component of lake ecosystems, yet large-scale responses to anthropogenic activity remain elusive. Here, we assess the ecological impact of land use on bacterial communities from over 200 lakes covering more than 660,000 km2 across Eastern Canada. In addition to community variation between ecozones, land use across Eastern Canada also appeared to alter diversity, community composition, and network structure. Specifically, increasing anthropogenic impact within the watershed lowered diversity. Likewise, community composition was significantly correlated with agriculture and urban development within a watershed. Interaction networks showed decreasing complexity and fewer keystone taxa in impacted lakes. Moreover, we identified potential indicator taxa of high or low lake water quality. Together, these findings point to detectable bacterial community changes of largely unknown consequences induced by human activity within lake watersheds.


Subject(s)
Ecosystem , Lakes , Agriculture , Bacteria/genetics , Canada , Humans
4.
J Helminthol ; 94: e50, 2019 Apr 11.
Article in English | MEDLINE | ID: mdl-30973122

ABSTRACT

New therapeutic approaches are necessary to control strongyloidiasis due to the side effects of, and resistance to, currently available drugs thiabendazole, albendazole, and ivermectin. This study examined the anthelmintic properties of extracts and isolated compounds from Siparuna guianensis against Strongyloides venezuelensis eggs and larvae, using the egg hatching test (EHT) and larval motility test (LMT). Albendazole (0.025 mg/ml) and ivermectin (0.316 mg/ml) were used as the positive controls for the EHT and LMT assays, respectively. Strongyloides venezuelensis eggs or larvae (±50 specimens) were treated with ethanol extract (0.05-1.0 mg/ml), ethyl acetate and aqueous fractions (0.05-0.8 mg/ml), essential oil (0.2-1.0 mg/ml) and α-bisabolol (0.2-1.0 mg/ml) from S. guianensis, and analysed by optical microscopy after 48 h (EHT), or after 24, 48 and 72 h (LMT). All the tested compounds exhibited ovicidal activity equivalent to the positive control and changed the morphology of the eggs. The S. guianensis ethanol extract and aqueous fraction were as effective as the positive control. Phytochemical analysis of the ethanol extract and fractions revealed the presence of phenolic compounds, tannins and flavonoids. Therefore, S. guianensis is effective against S. venezuelensis eggs and larvae in vitro, and can be considered as a potential alternative treatment for strongyloidiasis.


Subject(s)
Anthelmintics/pharmacology , Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Strongyloides/drug effects , Tracheophyta/chemistry , Animals , Anthelmintics/chemistry , Larva/drug effects , Monocyclic Sesquiterpenes/chemistry , Monocyclic Sesquiterpenes/pharmacology , Oils, Volatile/chemistry , Ovum/drug effects , Plant Extracts/chemistry
5.
Metallomics ; 9(9): 1271-1278, 2017 09 20.
Article in English | MEDLINE | ID: mdl-28795724

ABSTRACT

Mercury exposure is considered to be a public health problem due to the generation of toxic effects on human health as a result of environmental and occupational conditions. The inorganic form of mercury (HgCl2) can cause several biological changes in cells and tissues through its cumulative toxic potential, but little has been experimentally proven about the effects of inorganic mercury on salivary glands, an important modulator organ of oral health. This study analyzes the effects of prolonged low dose exposure to HgCl2 on the salivary glands of rats. Adult animals received a dose of 0.375 mg kg-1 day-1 over a period of 45 days. The parotid and submandibular glands were collected for analysis of the mercury levels and evaluation of oxidative stress, histological parameters and immunomodulation for metallothionein I and II (MT-I/II). In this investigation, biochemical and tissue changes in the salivary glands were verified due to the mercury levels, causing reduction in antioxidant capacity against peroxyl radicals, with consequent cellular lipid peroxidation and an increase in nitrite levels, volumetric changes and cytoskeletal damage in the submandibular glands, with less severe damage to the parotid glands. The results also have shown the occurrence of a cytoprotection mechanism due to increased MT-I/II expression, but not enough to avoid the morphology and oxidative damage. This evidence highlights, for the first time, that inorganic mercury is able to alter the morphology and oxidative biochemistry in salivary glands when exposed for a long time in low doses.


Subject(s)
Mercuric Chloride/toxicity , Mercury/metabolism , Oxidative Stress/drug effects , Salivary Glands/drug effects , Animals , Cytoskeleton/drug effects , Cytoskeleton/metabolism , Lipid Peroxidation/drug effects , Male , Metallothionein/metabolism , Nitrites/metabolism , Organ Size/drug effects , Rats, Wistar , Salivary Glands/anatomy & histology , Salivary Glands/metabolism
6.
Arch Pediatr ; 24(3): 225-230, 2017 Mar.
Article in French | MEDLINE | ID: mdl-28131558

ABSTRACT

In routine practice, intensive care physicians rarely have to manage children under 18years of age, particularly those under 15. This study's objectives were to assess the quality of training in pediatrics of adult intensive care teams, to document the workload generated by care of pediatric patients, and to identify the difficulties encountered in managing minors as patients. A survey was administered in Lower Normandy from 4 April 2012 to 1 September 2012. Physicians, residents, nurses, and nurses' aides practicing in one of the nine intensive care units of Lower Normandy were asked to complete an electronic or paper format questionnaire. This questionnaire assessed their level of pediatric training, the workload management of pediatric patients entailed, and the challenges posed by these patients. One hundred and nine questionnaires were returned (by 26 attending physicians, 18 residents, 38 nurses, and 27 nurses' aides). Eighty-three of the respondents (76%) had no experience in a pediatric unit of any kind. Forty-two percent thought that the pediatric age range lies between 3months and 15years of age. However, more than 50% of respondents would like the upper limit to be 16years or even older. Ninety-three respondents (85%) estimated having some exposure to pediatric patients in their routine practice, but this activity remained quite low. Seventy-three (67%) reported difficulties with the management of these young patients. This survey provides current information regarding the level of training of adult intensive care unit professionals and their concerns about managing patients under 18years of age, both in terms of workload and specific challenges.


Subject(s)
Intensive Care Units/organization & administration , Patient Care Team/organization & administration , Pediatrics/education , Transition to Adult Care/organization & administration , Workload , Adolescent , Adult , Child, Preschool , Clinical Competence , Female , France , Humans , Infant , Inservice Training , Male , Quality Assurance, Health Care/organization & administration , Resuscitation/education , Surveys and Questionnaires , Young Adult
7.
Braz J Med Biol Res ; 49(11): e5238, 2016.
Article in English | MEDLINE | ID: mdl-27828666

ABSTRACT

Early nutrition plays a long-term role in the predisposition to chronic diseases and influences the metabolism of several drugs. This may happen through cytochromes P450 (CYPs) regulation, which are the main enzymes responsible for the metabolism of xenobiotics. Here, we analyzed the effects of maternal protein restriction (MPR) on the expression and activity of hepatic offspring's CYPs during 90 days after birth, using Wistar rats as a mammal model. Hepatic CYP1A1, CYP1A2, CYP2B1, CYP2B2 and CYP2E1 mRNA and protein expression, and associated catalytic activities (ECOD, EROD, MROD, BROD, PROD and PNPH) were evaluated in 15-, 30-, 60-, and 90-day-old offspring from dams fed with either a 0% protein (MPR groups) or a standard diet (C groups) during the 10 first days of lactation. Results showed that most CYP genes were induced in 60- and 90-day-old MPR offspring. The inductions detected in MPR60 and MPR90 were of 5.0- and 2.0-fold (CYP1A2), 3.7- and 2.0-fold (CYP2B2) and 9.8- and 5.8- fold (CYP2E1), respectively, and a 3.8-fold increase of CYP2B1 in MPR90. No major alterations were detected in CYP protein expression. The most relevant CYP catalytic activities' alterations were observed in EROD, BROD and PNPH. Nevertheless, they did not follow the same pattern observed for mRNA expression, except for an induction of EROD in MPR90 (3.5-fold) and of PNPH in MPR60 (2.2-fold). Together, these results suggest that MPR during lactation was capable of altering the expression and activity of the hepatic CYP enzymes evaluated in the offspring along development.


Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Diet, Protein-Restricted , Lactation/metabolism , Liver/enzymology , Animals , Aryl Hydrocarbon Hydroxylases/metabolism , Cytochrome P-450 CYP1A1/metabolism , Cytochrome P-450 CYP1A2/metabolism , Cytochrome P-450 CYP2B1/metabolism , Cytochrome P-450 CYP2E1/metabolism , Female , Models, Animal , Rats , Rats, Wistar , Steroid Hydroxylases/metabolism , Time Factors
8.
Braz. j. med. biol. res ; 49(11): e5238, 2016. graf
Article in English | LILACS | ID: lil-797893

ABSTRACT

Early nutrition plays a long-term role in the predisposition to chronic diseases and influences the metabolism of several drugs. This may happen through cytochromes P450 (CYPs) regulation, which are the main enzymes responsible for the metabolism of xenobiotics. Here, we analyzed the effects of maternal protein restriction (MPR) on the expression and activity of hepatic offspring’s CYPs during 90 days after birth, using Wistar rats as a mammal model. Hepatic CYP1A1, CYP1A2, CYP2B1, CYP2B2 and CYP2E1 mRNA and protein expression, and associated catalytic activities (ECOD, EROD, MROD, BROD, PROD and PNPH) were evaluated in 15-, 30-, 60-, and 90-day-old offspring from dams fed with either a 0% protein (MPR groups) or a standard diet (C groups) during the 10 first days of lactation. Results showed that most CYP genes were induced in 60- and 90-day-old MPR offspring. The inductions detected in MPR60 and MPR90 were of 5.0- and 2.0-fold (CYP1A2), 3.7- and 2.0-fold (CYP2B2) and 9.8- and 5.8– fold (CYP2E1), respectively, and a 3.8-fold increase of CYP2B1 in MPR90. No major alterations were detected in CYP protein expression. The most relevant CYP catalytic activities’ alterations were observed in EROD, BROD and PNPH. Nevertheless, they did not follow the same pattern observed for mRNA expression, except for an induction of EROD in MPR90 (3.5-fold) and of PNPH in MPR60 (2.2-fold). Together, these results suggest that MPR during lactation was capable of altering the expression and activity of the hepatic CYP enzymes evaluated in the offspring along development.


Subject(s)
Animals , Female , Rats , Cytochrome P-450 Enzyme System/metabolism , Diet, Protein-Restricted , Lactation/metabolism , Liver/enzymology , Aryl Hydrocarbon Hydroxylases/metabolism , Cytochrome P-450 CYP1A1/metabolism , Cytochrome P-450 CYP1A2/metabolism , Cytochrome P-450 CYP2B1/metabolism , Cytochrome P-450 CYP2E1/metabolism , Models, Animal , Rats, Wistar , Steroid Hydroxylases/metabolism , Time Factors
9.
Nutr Hosp ; 24(4): 422-8, 2009.
Article in English | MEDLINE | ID: mdl-19721921

ABSTRACT

Conjugated linoleic acid (CLA) refers to a family of polyunsaturated fatty acids, being represented by a group of isomers of linoleic acid called conjugated for having a double bound after a simple bound. Among its isomers, trans-10,cis-12 and cis-9, cis-12 CLA stand out. These isomers can lead to different effects on the body: anticarcinogenic, antidiabetogenic, antiatherogenesis and positive body composition alteration. The objective of this review is to describe their mechanisms of action, effects on body composition, on plasmatic lipoproteins and supplementation. Studies about CLA supplementation show its capacity of reducing fat percentage, body mass and of promoting an improvement in lipid metabolism. One of the adverse effects attributed to one of the isomers is insulin resistance by body fat redistribution. Limitations in the scientific models used in CLA researches make impossible to draw conclusions about the action of this fatty acid on human metabolism.


Subject(s)
Body Composition , Linoleic Acids, Conjugated/physiology , Lipoproteins/blood , Animals , Dietary Supplements/adverse effects , Humans
10.
Nutr. hosp ; 24(4): 422-428, jul.-ago. 2009.
Article in English | IBECS | ID: ibc-73505

ABSTRACT

Conjugated linoleic acid (CLA) refers to a family of polyunsaturated fatty acids, being represented by a group of isomers of linoleic acid called conjugated for having a double bound after a simple bound. Among its isomers, trans-10,cis-12 and cis-9, cis-12 CLA stand out. These isomers can lead to different effects on the body: anticarcinogenic, antidiabetogenic, antiatherogenesis and positive body composition alteration. The objective of this review is to describe their mechanisms of action, effects on body composition, on plasmatic lipoproteins and supplementation. Studies about CLA supplementation show its capacity of reducing fat percentage, body mass and of promoting an improvement in lipid metabolism. One of the adverse effects attributed to one of the isomers is insulin resistance by body fat redistribution. Limitations in the scientific models used in CLA researches make impossible to draw conclusions about the action of this fatty acid on human metabolism (AU)


El ácido linoleico conjugado (CLA) es un ácido graso que pertenece al grupo de los ácidos grasos poliinsaturados, representado por el conjunto de isómeros del ácido linoleico, que son denominados conjugados porque poseen una doble conexión tras una conexión simple. De entre sus isómeros se distinguen el trans-10,cis-12 y cis-9, cis-12 CLA. Estos isómeros son capaces de promover efectos distintos en el organismo: anticarcinogénesis, antidiabetogénesis, antiaterogénesis y cambios de composición corporal. El objetivo de esta revisión es describir sus mecanismos de acción, los efectos en las lipoproteínas plasmáticas, en la composición corporal y la suplementación. Los estudios acerca de la suplementación del CLA demuestran su capacidad de reducir el porcentaje de grasa, el peso corporal, y de mejorar el metabolismo lipídico. Sin embargo, unos de los efectos contrarios relacionados a uno de sus isómeros es la resistencia a la insulina a través de la redistribución de grasa corporal. Las limitaciones en los modelos científicos adoptados en investigaciones acerca del CLA nos quitan la posibilidad de hacer conclusiones cuanto a la acción de este ácido graso en el metabolismo humano (AU)


Subject(s)
Humans , Linoleic Acids, Conjugated/physiology , Body Composition , Lipoproteins/blood , Dietary Supplements/adverse effects
12.
J Food Sci ; 74(2): C100-5, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19323722

ABSTRACT

Stewed beef and grilled dry aged beef were analyzed as part of an in-depth analytical program, with the aim of creating new flavors incorporating only compounds identified in the target foods and identifying new synthesis targets. In-house GC-MS analyses of several types of cooked beef have identified over 1000 volatile and semivolatile components; many for the 1st time. Among the semivolatiles detected were ten 2, 5-diketopiperazines (cyclic dipeptides) previously unreported in beef. These cyclic dipeptides are cis-cyclo(L-Ile-L-Pro), cis-cyclo(L-Leu-L-Pro), cis-cyclo(L-Pro-L-Pro), cis-cyclo(L-Pro-L-Val), cis-cyclo(L-Ala-L-Pro), cyclo(Gly-L-Pro), cyclo(Gly-L-Leu), cis-cyclo(L-Met-L-Pro), cis-cyclo(L-Phe-L-Pro), and cis-cyclo(L-Phe-L-Val). All 10 cyclic dipeptides were synthesized and evaluated organoleptically. Among them cis-cyclo(L-Leu-L-Pro), cis-cyclo(L-Met-L-Pro), and cis-cyclo(L-Phe-L-Pro) were found to be of particular organoleptic interest.


Subject(s)
Diketopiperazines/analysis , Meat/analysis , Animals , Cattle , Chromatography, Gas , Cooking , Diketopiperazines/chemistry , Diketopiperazines/isolation & purification , Dipeptides/analysis , Dipeptides/isolation & purification , Gas Chromatography-Mass Spectrometry , Humans , Odorants , Taste , Volatile Organic Compounds/analysis , Volatile Organic Compounds/isolation & purification
13.
Arch Pediatr ; 16(3): 294-8, 2009 Mar.
Article in French | MEDLINE | ID: mdl-19171468

ABSTRACT

An asthmatic girl was first hospitalized at age 2(9/12) years because of dyspnoea, lung consolidations and/or atelectasis, and rattling. Between ages 2(9/12) and 6(2/12) years, she required three hospitalizations in ICU out of nine hospitalizations for the same symptoms. Differential diagnosis of this difficult to treat asthma disclosed severe tracheomalacia and persistent asthma. Treatments given according to the clinical, radiological and functional findings failed to decrease frequency and severity of acute respiratory episodes. Eventually, positive pressure ventilation delivered at airway opening (via a mouthpiece) associated to active respiratory physiotherapy succeeded in removing atelectasis and quickly cured the five following acute episodes without any further hospitalization. This case report is about diagnosis procedure, intricate asthma and tracheomalacia, and open mind to unusual therapeutics that may disclose potential help.


Subject(s)
Asthma/complications , Positive-Pressure Respiration , Tracheomalacia/etiology , Tracheomalacia/therapy , Child , Female , Hospitalization/statistics & numerical data , Humans , Pulmonary Atelectasis/etiology , Pulmonary Atelectasis/therapy
16.
Anim Genet ; 38(5): 474-84, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17697135

ABSTRACT

Ten genes (ANK1, bR10D1, CA3, EPOR, HMGA2, MYPN, NME1, PDGFRA, ERC1, TTN), whose candidacy for meat-quality and carcass traits arises from their differential expression in prenatal muscle development, were examined for association in 1700 performance-tested fattening pigs of commercial purebred and crossbred herds of Duroc, Pietrain, Pietrain x (Landrace x Large White), Duroc x (Landrace x Large White) as well as in an experimental F(2) population based on a reciprocal cross of Duroc and Pietrain. Comparative sequencing revealed polymorphic sites segregating across commercial breeds. Genetic mapping results corresponded to pre-existing assignments to porcine chromosomes or current human-porcine comparative maps. Nine of these genes showed association with meat-quality and carcass traits at a nominal P-value of < or = 0.05; PDGFRA revealed no association reaching the P < or = 0.05 threshold. In particular, HMGA2, CA3, EPOR, NME1 and TTN were associated with meat colour, pH and conductivity of loin 24 h postmortem; CA3 and MYPN exhibited association with ham weight and lean content (FOM) respectively at P-values of < 0.003 that correspond to false discovery rates of < 0.05. However, none of the genes showed significant associations for a particular trait across all populations. The study revealed statistical-genetic evidence for association of the functional candidate genes with traits related to meat quality and muscle deposition. The polymorphisms detected are not likely causal, but markers were identified that are in linkage disequilibrium with causal genetic variation within particular populations.


Subject(s)
Gene Expression Profiling , Meat , Muscle Development/genetics , Muscle, Skeletal/embryology , Muscle, Skeletal/physiology , Swine/genetics , Animals , Chromosome Mapping , Swine/physiology
17.
Dentomaxillofac Radiol ; 36(5): 256-62, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17586851

ABSTRACT

OBJECTIVES: Radiographic evaluation of periodontal conditions is a difficult process because of the many limitations inherent to this complementary examination and the lack of image specificity for different types of bone defects. The objectives of this study are to utilize digitized imaging resources to describe the radiographic features of different types of periodontal bone defects produced artificially in dry mandibles. METHODS: 14 dry mandibles were utilized, in which periodontal bone defects were produced. Digital photographs and conventional radiographs of each site were obtained in a standardized manner, before and after producing these defects. The radiographs were then digitized, displayed on the screen and evaluated by three examiners. RESULTS: Most of the bone defects presented distinct imaging characteristics that allowed them to be identified, with the exception of one-, two- and three-wall infrabony defects. The defects that were most easily interpreted were horizontal and vertical defects and the most difficult were defects in the radicular septum. CONCLUSIONS: Despite the importance of imaging diagnoses in reaching clinical decisions regarding treatment, such diagnoses for different types of periodontal bone defects are extremely difficult to make. In the present study, the utilization of digital tools for interpreting digitized radiographic images facilitated the process.


Subject(s)
Alveolar Bone Loss/diagnostic imaging , Radiographic Image Interpretation, Computer-Assisted , Radiography, Dental, Digital , Cadaver , Humans , Mandible/diagnostic imaging , Observer Variation
18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(3 Pt 1): 031112, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17500673

ABSTRACT

We investigate the critical behavior of a model with two coupled critical densities, one of which is diffusive. The model simulates the propagation of an epidemic process in a population, which uses the underlying lattice to leave a track of the recent disease history. We determine the critical density of the population above which the system reaches an active stationary state with a finite density of active particles. We also perform a scaling analysis to determine the order parameter, the correlation length, and critical relaxation exponents. We show that the model does not belong to the usual directed percolation universality class and is compatible with the class of directed percolation with diffusive and conserved fields.

19.
Dentomaxillofac Radiol ; 35(2): 83-7, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16549434

ABSTRACT

OBJECTIVES: The purpose of this study was to evaluate the reliability of direct and indirect measurement methods, with a view to standardizing morphometry instruments. METHODS: Dry skulls of 30 New Zealand rabbits were used. Measurements were made with a transparent flexible plastic ruler, an EKG calliper and a digital calliper, as well as with computerized tomography and lateral radiographs for direct and indirect analysis of distances and angles. RESULTS: The different instruments studied showed only partial agreement. CONCLUSIONS: A standardized and reliable direct or indirect morphometry method for the craniofacial skeleton of rabbits still has not been determined.


Subject(s)
Cephalometry/methods , Facial Bones/growth & development , Skull/growth & development , Animals , Calibration , Cephalometry/instrumentation , Cephalometry/statistics & numerical data , Facial Bones/diagnostic imaging , Male , Mandible/diagnostic imaging , Mandible/growth & development , Maxilla/diagnostic imaging , Maxilla/growth & development , Nasal Bone/diagnostic imaging , Nasal Bone/growth & development , Occipital Bone/diagnostic imaging , Occipital Bone/growth & development , Orbit/diagnostic imaging , Orbit/growth & development , Rabbits , Reproducibility of Results , Skull/diagnostic imaging , Sphenoid Bone/diagnostic imaging , Sphenoid Bone/growth & development , Tomography, Spiral Computed , Vertical Dimension
20.
Meat Sci ; 67(4): 651-67, 2004 Aug.
Article in English | MEDLINE | ID: mdl-22061815

ABSTRACT

A study in 192 entire male pigs examined the effects of breed, diet and muscle on growth, fatness, sensory traits and fatty acid composition. There were four breeds: two modern breeds, Duroc and Large White and two traditional breeds, Berkshire and Tamworth. The diets differed in energy:protein ratio, being conventional (C) and low protein (LP) diets, respectively. Muscles investigated were the `white' longissimus dorsi (LD) and the `red' psoas major (PS). Breed influenced growth rate and fatness, the modern breeds being faster-growing with leaner carcasses. However, the concentrations of neutral lipid fatty acids and marbling fat (neutral lipid+phosopholipid fatty acids) were higher in Berkshire and Duroc, in both LD and PS. Relationships between marbling fat and P2 fat thickness showed clear breed effects, with Duroc having high marbling fat at low P2 and Tamworth low marbling fat at high P2. Breed effects on sensory scores given by the trained taste panel to griddled LD and PS steaks were relatively small. Breed affected the fatty acid composition of intramuscular neutral lipid, with high % values for the saturated fatty acids, 14:0 and 16:0 in Berkshire and Tamworth (fat carcasses) and high values for polyunsaturated fatty acids in Duroc and Large White (lean carcasses). Duroc had particularly high concentrations of the long-chain polyunsaturated fatty acids, 20:5n-3 and 22:6n-3 in phospholipid of both muscles. Diet influenced growth rate and fatness, the LP diet slowing growth and producing fatter meat, more so in the two modern breeds, and particularly in intramuscular rather than subcutaneous fat. This diet produced more tender and juicy meat, although pork flavour and flavour liking were reduced. The PS muscle had higher tenderness, juiciness, pork flavour, flavour liking and overall liking scores than LD. The concentration of phospholipid fatty acids was higher in PS than LD but neutral lipid fatty acid content and marbling fat were higher in LD.

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