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1.
PLoS One ; 19(5): e0300813, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38753730

RESUMO

Myxomatous mitral valve disease (MMVD) is the most common cardiovascular disorder in dogs with a high prevalence, accounting for approximately 75% of all canine heart disease cases. MMVD is a complex disease and shows variable progression from mild valve leakage to severe regurgitation, potentially leading to heart failure. However, the molecular mechanisms and age-related changes that govern disease progression, especially at the early stage (B1) before the development of discernable clinical signs, remain poorly understood. In this prospective study, we aimed to compare gene expression differences between blood samples of aged beagle dogs with stage B1 MMVD and those of healthy controls using RNA sequencing. Clinical evaluation was also conducted, which revealed minimal differences in radiographic and echocardiographic measurements despite distinct biomarker variations between the two groups. Comparative transcriptomics revealed differentially expressed genes associated with extracellular matrix remodeling, prostaglandin metabolism, immune modulation, and interferon-related pathways, which bear functional relevance for MMVD. In particular, the top 10 over- and under-expressed genes represent promising candidates for influencing pathogenic changes in MMVD stage B1. Our research findings, which include identified variations in clinical markers and gene expression, enhance our understanding of MMVD. Furthermore, they underscore the need for further research into early diagnosis and treatment strategies, as, to the best of our knowledge, no prior studies have explored the precise molecular mechanisms of stage B1 in MMVD through total RNA sequencing.


Assuntos
Doenças do Cão , Análise de Sequência de RNA , Animais , Cães , Doenças do Cão/genética , Doenças do Cão/patologia , Masculino , Feminino , Valva Mitral/patologia , Doenças das Valvas Cardíacas/genética , Doenças das Valvas Cardíacas/veterinária , Doenças das Valvas Cardíacas/patologia , Transcriptoma , Estudos Prospectivos , Perfilação da Expressão Gênica
2.
Front Vet Sci ; 10: 1153702, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37732139

RESUMO

Inflammatory bowel disease is a common condition in cats, characterized by recurring gastrointestinal signs with histologic evidence of intestinal inflammation. A 9-month-old neutered male Sphynx cat was presented with a 5-week history of vomiting and hematochezia. Conservative patient management with a therapeutic gastrointestinal formula, antibiotics, and antiemetics resulted in a positive response to treatment, with relapse of signs when the medications were discontinued. A new finding of marked eosinophilia and basophilia was identified 3 months after the initial presentation. Colonoscopy revealed cecal erosions and a surgical biopsy with histopathology confirmed a diagnosis of lymphocytic-plasmacytic and eosinophilic enterocolitis. For this diagnosis, the patient was treated with prednisolone, tylosin, and metronidazole. Antibiotics were gradually tapered as the cat showed clinical improvement. The patient showed resolution of the gastrointestinal signs, and the numbers of eosinophils and basophils returned within the reference range 8 weeks after the treatment began. Basophilia and eosinophilia has been reported in conjunction with feline T-cell lymphoma. However, marked basophilia accompanying eosinophilia is extremely rare in cats with inflammatory bowel disease. We herein provide clinical details, including ultrasonography, endoscopy, histopathology, and disease course of feline lymphocytic-plasmacytic and eosinophilic enterocolitis with marked basophilia and eosinophilia. This case highlights the importance of considering enteritis as potential diagnoses when eosinophilia and basophilia are concurrently observed in cats.

3.
Vet Med Sci ; 9(6): 2504-2512, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37766491

RESUMO

BACKGROUND: Bone-subtraction computed tomography angiography (CTA) (BSCTA) is a new technique designed to overcome the limitation of three-dimensional CTA, where the vessels surrounded by bone and calcification can be obscured. An optimal contrast CT protocol for intracranial artery visualization with BSCTA has yet to be established in dogs. OBJECTIVES: The purpose of this study was to determine the optimal contrast protocol of CTA for visualizing intracranial artery using an automatic bone-subtraction technique in dogs. METHODS: Brain CTA was performed four times for each of nine healthy beagle dogs to cover all the contrast protocols: two different contrast iodine concentrations (300 and 370 mgI/mL) and two different contrast media injection rates (2 and 4 mL/s). Bone removal post-processing was performed automatically by subtracting the non-enhanced CT data from the contrast CT data using a dedicated workstation. The bone-subtracted intracranial vessels were analysed for quantitative and qualitative evaluation. RESULTS: Quantitative evaluation showed significantly higher CT attenuation values for the group with a 370 mgI/mL iodine content at a rate of 4 mL/s than the two groups with a 300 mgI/mL iodine content at the rates of 2 and 4 mL/s (p < 0.001). Qualitative assessment revealed significantly higher mean scores for the 370 mgI/mL groups than the 300 mgI/mL groups and significantly higher mean scores for the 4 mL/s groups than the 2 mL/s groups (p < 0.05). CONCLUSIONS: The optimal contrast protocol for BSCTA suggests that high iodine material concentration and high injection rate should be used for strong arterial attenuation and great visualization of the intracranial arterial structure in dogs.


Assuntos
Angiografia por Tomografia Computadorizada , Iodo , Cães , Animais , Angiografia por Tomografia Computadorizada/veterinária , Meios de Contraste , Tomografia Computadorizada por Raios X/veterinária , Artérias
4.
Front Vet Sci ; 10: 1196006, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37519999

RESUMO

Emphysematous cystitis is an extremely rare, complicated urinary tract infection with the presence of gas in the bladder wall and lumen caused by gas-producing bacterial infections. A 7-year-old spayed female pomeranian dog was presented with a 3-day history of hematuria and pollakiuria (case 1), and a 9-year-old spayed female jindo dog was presented with a 4-day history of intermittent hematuria (case 2). Imaging modalities, including radiography, ultrasonography, and computed tomography, and bacterial culture tests were used for the diagnosis. Emphysematous cystitis due to Escherichia coli infection with the extension of gas into multiple locations was identified in both cases. Based on the results of antibiotic susceptibility testing, systemic antibiotics were initiated. Both animals had an excellent response to antibiotic treatment, and the clinical signs of the gas collection were completely resolved within ~1 month after treatment initiation. This response was sustained without recurrence in the follow-up period. This case report describes clinical details of extremely rare canine cases of emphysematous cystitis with the extension of gas into multiple locations and evaluates the clinical efficacy of antibiotic therapy.

5.
Genes (Basel) ; 13(11)2022 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-36360165

RESUMO

Reference genes are crucial in molecular biological studies as an internal control for gene re-search as they exhibit consistent expression patterns across many tissue types. In canines, radiation therapy is the most important therapeutic tool to cure various diseases like cancer. However, when using radiation for therapeutic strategy, radiation exposure to healthy tissues leads to some possible side effects such as acute radiation-induced skin injury and alters gene expression. Therefore, the analysis of a change in reference gene expression during the skin recovery process after radiation therapy is essential in healthy canine tissue. In the present study, we analyzed eight reference genes (ACTB, GAPDH, YWHAZ, GUSB, HPRT1, RPL4, RPS5, and TBP) in canine dermal tissues at 0, 1, 2, 3, 4, 5, 7, and 9 weeks of radiation exposure that affected the skin condition of canines. The stability of reference genes is determined by evaluating radiation therapy's effect on healthy canine dermal tissue. Epidermal marker, Keratin 10 expression varies each week after irradiation, and HPRT1 is found to be the most suitable for normalization of mRNA expression in radiation-exposed canine dermal tissues. Changes in the gene expression level were evaluated by using a reliable tool such as quantitative real-time polymerase chain reaction (qRT-PCR). In order to achieve a valid qRT-PCR result, the most stable reference genes used for normalization after the radiation exposure process are important. Therefore, the current study was designed to evaluate the most stable reference gene for the post-irradiation canine tissues. After radiation exposure, the alternation of reference gene expression was estimated by three algorithms (geNorm, Normfinder, and Bestkeeper). The RG validation programs (GeNorm and NormFinder) suggested that HPRT1, RPL4, and TBP were suitable for normalization in qRT-PCR. Furthermore, three algorithms suggested that HPRT1 was the most stable reference gene for normalization with qRT-PCR results, regardless of before and after radiation exposure. Whereas GAPDH was found to be the most unstable reference gene. In addition, the use of stable or unstable reference genes for the normalization of Keratin 10 expression showed statistical differences. Therefore, we observed that, to obtain accurate and suitable PCR results of the canine tissues with and without radiation exposure, the HPRT1 reference gene is recommended for normalization with its high stability. Additionally, the use of RGs such as HPRT1, RPL4, and TBP for normalization in qRT-PCR experiments is recommended for post-radiation canine tissues to generate more accurate and reliable data. These results will provide fundamental information regarding internal controls for gene expression studies and can be used for the analysis of gene patterns in regenerative medicine.


Assuntos
Algoritmos , Queratina-10 , Cães , Animais , Queratina-10/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
6.
Vet Sci ; 9(7)2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35878339

RESUMO

A 4-year-old spayed female miniature poodle dog presented with a 1-week history of acute tetraparesis. A neurological examination revealed severe neck pain and non-ambulatory tetraparesis. Computed tomography and magnetic resonance imaging showed hypoplastic dens with moderate compression of the spinal cord at C1-C2. The atlantoaxial subluxation (AAS) was surgically stabilized using ventral pins and polymethylmethacrylate (PMMA) cement. On the second postoperative day, the patient showed significant dyspnea, and aspiration pneumonia was identified on radiography. The patient exhibited dysphagia with abnormal food prehension and an inability to protrude the tongue, with no gag reflex. We tentatively diagnosed the patient with multiple cranial nerve (CN) palsies involving the 9th, 10th, and 12th CNs following surgical ventral stabilization. The protruding cranial part of the implanted PMMA cement, which could mechanically contribute to the corresponding CNs dysfunction, was surgically removed. The symptoms gradually improved, and the patient showed normal tongue movement 1 month after revision surgery. In conclusion, we report herein a canine case of multiple CN palsies following ventral stabilization surgery for AAS. The experience gained from this case suggests an optimized management plan for postoperative neurological complications associated with ventral stabilization.

7.
Korean J Parasitol ; 60(2): 127-131, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35500894

RESUMO

Feline hemotropic mycoplasmosis (hemoplasmosis) is an infection of the red blood cells caused by the Mycoplasma haemofelis (Mhf), Candidatus Mycoplasma haemominutum (CMhm), and Candidatus Mycoplasma turicensis (CMt). The existence of Mhf, CMhm, and CMt has been demonstrated in feral cats in Korea using molecular methods, but no clinical cases have yet been reported. This study reports 2 clinical cases of hemotropic mycoplasmosis caused by CMhm and CMt in 2 anemic cats. The first case was a client-owned intact female domestic shorthair cat that presented with fever, pale mucous membranes, and normocytic normochromic non-regenerative anemia. Prior to referral, an immunosuppressive prednisolone dose was administered at the local veterinary clinic for 1 month. The cat was diagnosed with high-grade alimentary lymphoma. Organisms were found on the surface of the red blood cells on blood smear examination. The second case was of a rescued cat that presented with dehydration and fever. The cat had normocytic normochromic non-regenerative anemia. Necropsy revealed concurrent feline infectious peritonitis. Polymerase chain reaction assay targeting 16S rRNA revealed CMhm infection in case 1 and dual infection of CMhm and CMt in case 2. Normocytic normochromic non-regenerative anemia was observed in both cats before and during the management of the systemic inflammation. This is the first clinical case report in Korea to demonstrate CMhm and CMt infections in symptomatic cats.


Assuntos
Anemia , Infecções por Mycoplasma , Mycoplasma , Anemia/diagnóstico , Anemia/veterinária , Animais , Gatos , Feminino , Mycoplasma/genética , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/veterinária , RNA Ribossômico 16S/genética
8.
Vet Q ; 42(1): 41-47, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35068361

RESUMO

Bacillus amyloliquefaciens is a gram-positive bacterial species that is utilised as a probiotic in humans and animals. There are no reports of infective endocarditis (IE) in dogs. An 8-year-old, spayed, female Maltese presented with a 1-month history of fever, depression, weight loss, and hindlimb lameness. Laboratory test results indicated non-regenerative anaemia, neutrophilia, hyperglobulinemia, and proteinuria. Echocardiography revealed vegetation on the septal leaflet of the mitral valve and thromboemboli in the left atrium. Consecutive blood culture results revealed that the blood samples were consistently positive for Bacillus amyloliquefaciens, which is generally considered a probiotic bacterial species for animals. Broad-spectrum antibiotics (amoxicillin-clavulanic acid and cefotaxime) and anticoagulants (clopidogrel and rivaroxaban) were administered for 4 months. The clinical signs were responsive to antibiotic treatment. After 4 months, the dog was no longer febrile and the size of the thromboemboli in the left atrium had decreased. Bacteria were no longer isolated in blood cultures after antibiotic therapy. To the best of our knowledge, this is the first case report of canine IE caused by bactaeremic infection with Bacillus amyloliquefaciens.


Assuntos
Bacillus amyloliquefaciens , Doenças do Cão , Endocardite Bacteriana , Endocardite , Animais , Antibacterianos/uso terapêutico , Doenças do Cão/tratamento farmacológico , Cães , Ecocardiografia , Endocardite/tratamento farmacológico , Endocardite/veterinária , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/veterinária , Feminino , Valva Mitral/diagnóstico por imagem
9.
BMC Vet Res ; 16(1): 192, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532259

RESUMO

BACKGROUND: Combination therapy with glucocorticoids and adjunctive immunomodulating drugs has been generally accepted as a standard treatment regimen for meningoencephalomyelitis of unknown etiology (MUE). We hypothesized that treatment with MMF as an adjunctive agent along with glucocorticoids would be effective and well-tolerated protocol in dogs with MUE. Eighty-six dogs with MUE between May 2009 and June 2017 were included (59 females and 27 males; mean age of 5.93 years; mean body weight of 3.83 kg). The medical records of dogs with MUE treated with prednisolone and MMF were retrospectively evaluated to determine the therapeutic response, survival time, and treatment-related adverse effects. RESULTS: A partial or complete response (CR) was recorded for 75 dogs. The overall median survival time from the initiation of treatment was 558 days. Dogs that showed CR with no relapse over the treatment period (from diagnosis to death) had significantly longer median survival times. A significantly higher mortality hazard ratio of 4.546 was recorded in dogs that failed to achieve CR. The interval between the onset of clinical signs and the clinical presentation was not significantly associated with CR, relapse rate, and survival time. Adverse effects included gastrointestinal upsets in 26 dogs (30.23%), sporadic infections in 17 dogs (19.77%), and pancreatitis in seven dogs (8.14%). CONCLUSIONS: The results suggest that adjunctive MMF treatment for MUE is safe and comparable to other immunosuppressive protocols. The treatment should focus on the achievement of CR and preventing relapse for successful management.


Assuntos
Doenças do Cão/tratamento farmacológico , Meningoencefalite/veterinária , Ácido Micofenólico/uso terapêutico , Prednisolona/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Cães , Quimioterapia Combinada/veterinária , Feminino , Imunossupressores/uso terapêutico , Masculino , Meningoencefalite/tratamento farmacológico , Meningoencefalite/mortalidade , Ácido Micofenólico/efeitos adversos , Prednisolona/efeitos adversos , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
10.
Vet Med Sci ; 6(4): 965-974, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32585777

RESUMO

BACKGROUND: Given the active research on targeted therapy using tyrosine kinase (TK) inhibitors (TKIs) in the field of oncology, further studies have recently been conducted to evaluate their use in autoimmune disorders. Based on immunological investigations, previous studies have suggested that granulomatous meningoencephalomyelitis (GME) and necrotizing encephalomyelitis (NE) are similar to multiple sclerosis (MS), which is a human autoimmune demyelinating central nervous system disease. OBJECTIVES: Considering this perspective, we hypothesized that canine GME and NE have significant expression of one or more TKs, which are associated with human MS pathogenesis. METHODS: To determine the possible use of conventional multi-targeted TKIs as a treatment for canine GME and NE, we characterized the immunohistochemical expression of platelet-derived growth factor receptor (PDGFR)-α, PDGFR-ß, vascular endothelial growth factor receptor (VEGFR)-2, c-Abl and c-Kit in GME and NE samples. RESULTS: Histological samples from four dogs with GME and three with NE were retrieved. All samples stained positive for PDGFR-ß (7/7 [100%]). PDGFR-α and c-Kit were expressed in 3/7 (42.8%) samples each. c-Abl was identified in 2/7 (28.5%) samples; no sample showed VEGFR-2 (0%) expression. Co-expression of TKs was identified in 6/7 (85.7%) dogs. CONCLUSIONS: All samples were positive for at least one or more of PDGFR-α, PDGFR-ß, c-Kit and c-Abl, which are known as the target TKs of conventional multi-targeted TKIs. Their presence does suggest that these TKs may play a role in the pathogenesis of GME and NE. Therefore, multi-targeted TKIs may provide benefits in the treatment of canine GME and NE by suppressing the activity of these TKs.


Assuntos
Doenças do Cão/genética , Encefalite/veterinária , Expressão Gênica , Meningoencefalite/veterinária , Animais , Cães , Encefalite/genética , Feminino , Masculino , Meningoencefalite/genética , Proteínas Proto-Oncogênicas c-abl/genética , Proteínas Proto-Oncogênicas c-abl/metabolismo , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/genética , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
11.
J Vet Sci ; 20(4): e44, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31364328

RESUMO

This study evaluated the feasibility of using texture analysis and machine learning to distinguish radiographic lung patterns. A total of 1200 regions of interest (ROIs) including four specific lung patterns (normal, alveolar, bronchial, and unstructured interstitial) were obtained from 512 thoracic radiographs of 252 dogs and 65 cats. Forty-four texture parameters based on eight methods of texture analysis (first-order statistics, spatial gray-level-dependence matrices, gray-level-difference statistics, gray-level run length image statistics, neighborhood gray-tone difference matrices, fractal dimension texture analysis, Fourier power spectrum, and Law's texture energy measures) were used to extract textural features from the ROIs. The texture parameters of each lung pattern were compared and used for training and testing of artificial neural networks. Classification performance was evaluated by calculating accuracy and the area under the receiver operating characteristic curve (AUC). Forty texture parameters showed significant differences between the lung patterns. The accuracy of lung pattern classification was 99.1% in the training dataset and 91.9% in the testing dataset. The AUCs were above 0.98 in the training set and above 0.92 in the testing dataset. Texture analysis and machine learning algorithms may potentially facilitate the evaluation of medical images.


Assuntos
Pulmão/diagnóstico por imagem , Aprendizado de Máquina , Radiografia/veterinária , Algoritmos , Animais , Área Sob a Curva , Gatos , Cães , Feminino , Masculino , Curva ROC , Radiografia/métodos
12.
J Vet Sci ; 19(6): 840-845, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29929358

RESUMO

The purpose of this study was to propose a standard for differentiation between normal dogs and patients with hyperadrenocorticism (HAC) by measuring skin thickness via ultrasonography in small breed dogs. Significant changes in skin thickness of patients treated with prednisolone (PDS) or patients with HAC treated with trilostane were evaluated. Skin thickness was retrospectively measured on three abdominal digital images obtained from small breed dogs weighing < 15 kg that underwent abdominal ultrasonography. Mean skin thickness of normal dogs was 1.03 ± 0.25 mm (mean ± SD). Both the HAC and PDS groups showed significantly thinner skin than that in the normal group. Seven of the 10 HAC patients treated with trilostane had increased skin thickness. The area under the curve value of 0.807 was based on the receiver operating characteristics (ROC) curve for differentiating normal dogs from HAC patients. Sensitivity was 76% and specificity was 73% when skin thickness was less than the 0.83 mm cutoff value. In conclusion, measurement of skin thickness in small breed dogs by using ultrasonography is likely to provide clinical information useful in differentiating HAC patients from normal dogs. However, exposure to PDS, trilostane, and other conditions may have a significant effect on skin thickness.


Assuntos
Hiperfunção Adrenocortical/veterinária , Doenças do Cão/diagnóstico por imagem , Pele/diagnóstico por imagem , Ultrassonografia/veterinária , Hiperfunção Adrenocortical/diagnóstico por imagem , Hiperfunção Adrenocortical/patologia , Animais , Estudos de Casos e Controles , Doenças do Cão/patologia , Cães , Feminino , Glucocorticoides/farmacologia , Masculino , Prednisolona/farmacologia , Estudos Retrospectivos , Pele/efeitos dos fármacos , Pele/patologia
13.
J Vet Sci ; 19(2): 296-300, 2018 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-29169229

RESUMO

This study was carried out to derive and evaluate reference computed tomography (CT)-based indices for normal canine spine. CT and magnetic resonance images were acquired from 12 clinically normal Beagle dogs (normal group) and 50 dogs with 56 spinal disorders (patient group). Image acquisition regions were cervical spine (C2-T1), thoracic spine (T1-T13), and lumbar spine (L1-L7). Measured indices were: the ratios of width to height of the spinal cord including the dura matter (CR) and of the vertebral foramen (FR), and the ratio of the cross-sectional area of the spinal cord to that of the vertebral foramen (CFAR). Reliability analysis was performed to evaluate intermodality agreement. Student's t-tests and receiver operating characteristic curves were used to discriminate the normal and patient groups on CT. Intermodality agreements of the normal and patient groups were acceptable to excellent. The highest discriminating levels of CR at the vertebral body level and the intervertebral disc space level were 1.25 or more and 1.44 or more, respectively. FR and CFAR had the highest discriminating level at the cervical region. This report presents quantitative information on canine spinal morphometry; the obtained indices may be helpful for CT screening of dogs with spinal disorders.


Assuntos
Doenças do Cão/diagnóstico por imagem , Doenças da Coluna Vertebral/veterinária , Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/veterinária , Animais , Estudos de Casos e Controles , Cães , Feminino , Imageamento por Ressonância Magnética/veterinária , Masculino , Doenças da Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
14.
Environ Sci Technol ; 49(19): 11569-76, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26368392

RESUMO

This work develops an integrated model approach for estimating emissions from long-haul freight truck and rail transport in the United States between 2010 and 2050. We connect models of macroeconomic activity, freight demand by commodity, transportation networks, and emission technology to represent different pathways of future freight emissions. Emissions of particulate matter (PM), carbon monoxide (CO), nitrogen oxides (NOx), and total hydrocarbon (THC) decrease by 60%-70% from 2010 to 2030, as older vehicles built to less-stringent emission standards retire. Climate policy, in the form of carbon tax that increases apparent fuel prices, causes a shift from truck to rail, resulting in a 30% reduction in fuel consumption and a 10%-28% reduction in pollutant emissions by 2050, if rail capacity is sufficient. Eliminating high-emitting conditions in the truck fleet affects air pollutants by 20% to 65%; although these estimates are highly uncertain, they indicate the importance of durability in vehicle engines and emission control systems. Future infrastructure investment will be required both to meet transport demand and to enable actions that reduce emissions of air and climate pollutants. By driving the integrated model framework with two macroeconomic scenarios, we show that the effect of carbon tax on air pollution is robust regardless of growth levels.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/economia , Modelos Teóricos , Veículos Automotores , Ferrovias , Emissões de Veículos/análise , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , Monóxido de Carbono/análise , Política Ambiental , Hidrocarbonetos/análise , Modelos Econômicos , Veículos Automotores/economia , Óxidos de Nitrogênio/análise , Material Particulado/análise , Ferrovias/economia , Estados Unidos
15.
J Air Waste Manag Assoc ; 64(1): 2-12, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24620398

RESUMO

UNLABELLED: Freight transportation activities are responsible for a large share of air pollution and greenhouse gas emissions in the United States. Various freight transportation modes have significantly different impacts on air quality and environmental sustainability, and this highlights the need for a better understanding of interregional freight shipment mode choices. This paper develops a binomial logit market share model to predict interregional freight modal share between truck and rail as a function of freight and shipment characteristics. This model can be used to estimate the impacts of various factors, such as oil price, on shippers' mode choice decisions. A set of multiyear freight and geographical information databases was integrated to construct regression models for typical freight commodities. The atmospheric impact levels incurred by different freight modal choice decisions are analyzed to provide insights on the relationship among freight modal split, oil price change, and air quality. IMPLICATIONS: Freight transportation has become a major source of energy consumption and air pollution, and emissions rates vary significantly across different modes. Understanding freight shipment mode choice under various economic and engineering factors will help assess the environmental impacts of freight shipment systems at the national level. This paper develops a binomial logit model for two dominating modes (truck and rail) and shows how this model is incorporated into an environmental impact analysis. The framework will be useful to policy makers to assess the impacts of freight movements on air quality and public health and to mitigate those adverse impacts.


Assuntos
Poluição do Ar/prevenção & controle , Comércio/economia , Comércio/métodos , Meio Ambiente , Meios de Transporte/métodos , Modelos Teóricos , Reprodutibilidade dos Testes , Emissões de Veículos
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