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471.
Juan Carlos Camargo García Christoph Kleinn 《European Journal of Forest Research》2010,129(6):1213-1222
Three models for the prediction of bamboo culm length and two for culm volume were fitted from data of 303 guadua bamboo (Guadua angustifolia Kunth) culms. Data are from 101 temporary inventory plots systematically distributed over the coffee region of Colombia (inventory
area about 1,029,525 ha). Linear and non-linear regression models were used, and the precision of the models was evaluated
by cross-validation. The models were compared by studying the adjusted coefficient of determination, the bias, mean square
error and Akaike’s information criterion and by the F-test that compares predicted and observed values. For culm length, the best fit showed models that included predictor variables
related to stand characteristics such as quadratic mean diameter and number of culms per ha. For culm volume prediction, the
inclusion of culm length improved the model significantly. For the simple form factor model, precision of prediction was least.
The models developed are useful in facilitating the estimation of stand characteristics that are relevant for the silvicultural
management of Guadua stands and also for the assessment of their environmental services (such as carbon sequestration). 相似文献
472.
Powdered leaves of Clausena anisata and Plectranthus glandulosus were evaluated on Cameroonian and German strains of Sitophilus
zeamais and Prostephanus truncatus for their insecticidal activities, the effects on progeny production, grain damage and population increase by admixing powders
and maize grains. The two powders caused significant mortality of the three insects with P. glandulosus being far more effective than C. anisata. P. truncatus was less susceptible to P. glandulosus powder compared with the two strains of S. zeamais. The German strain (LD50 = 2.75 g/100 g grain) of S. zeamais was less susceptible to P. glandulosus powder than the Cameroonian strain (LD50 = 1.86 g/100 g grain). P. glandulosus unlike C. anisata powder, considerably reduced grain damage, progeny production and population increase. This study shows that there is a great
potential for the powder of P. glandulosus as a promising grain protectant for integration within the subsistence farming systems of sub-saharan Africa. 相似文献
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477.
Waldern NM Weishaupt MA Imboden I Wiestner T Lischer CJ 《American journal of veterinary research》2005,66(12):2095-2100
OBJECTIVE: To evaluate the effects of shock wave treatment on cutaneous nerve function, compared with the effects of local nerve block and sedation. ANIMALS: 18 clinically sound Swiss Warmbloods. PROCEDURE: Horses were randomly allocated to 3 groups and received different amounts and types of shock waves (extracorporeal shock wave treatment [ESWT] or radial pressure wave treatment [RPWT]). Horses were sedated with xylazine and levomethadone. Shock waves were applied to the lateral palmar digital nerve at the level of the proximal sesamoid bones on 1 forelimb. Skin sensitivity was evaluated by means of an electrical stimulus at the coronary band before and 5 minutes after sedation and at 4, 24, and 48 hours after application of ESWT or RPWT. On the contralateral forelimb, skin sensitivity was tested before and 10 minutes after an abaxial sesamoid nerve block. RESULTS: No significant changes in skin sensitivity were detected, regardless of the shock wave protocol applied. Mean reaction thresholds after sedation were more than twice the baseline thresholds. After the abaxial sesamoid block, no reaction was recorded in any of the horses. CONCLUSIONS AND CLINICAL RELEVANCE: Application of ESWT or RPWT to the palmar digital nerve had no effect on cutaneous sensation distal to the treated region for at least 2 days after application. The analgesic effect of sedation on reaction to electrical stimuli was distinct but varied among horses. 相似文献
478.
Christian Ulrichs Dominika Dolgowski Tanja Mucha Christoph Reichmuth Inga Mewis 《Gesunde Pflanzen》2005,57(5):110-116
Zusammenfassung Im Rahmen eines Umweltgutachtens wurde die phytotoxische und insektizide Wirkung von Steinkohlenflugasche untersucht. Als Testorganismen dienten die Pflanzen Tropaeolum majus (Kapuzinerkresse) und Lepidium sativum (Brunnenkresse) sowie die Vorratsschädlinge Plodia interpunctella (Dörrobstmotte), Tenebrio molitor (Mehlkäfer) und Sitophilus granarius (Kornkäfer). Gezeigt werden konnte, dass die verwendete Steinkohlenflugasche bei einem aus der Literatur entnommenen theoretischen täglichen Flugstaubniederschlag von 1 g/m2 keine phytotoxischen bzw. insektiziden Eigenschaften aufwies. Selbst eine zehnfach erhöhte Dosis von 10 g/m2 hatte innerhalb von 2 Tagen keine erhöhte Mortalität von Dörrobstmottenlarven bzw. über einen Zeitraum von 12 Tagen keine erhöhte Mortalität von Mehlkäfern (alle Entwicklungsstadien) zur Folge. Für Kornkäfer ergab sich eine leichte Erhöhung der Mortalität auf 2 % innerhalb von 12 Tagen nach einer Dosierung von 5 g/m2. Die Mortalitätsrate von Kornkäfern erhöhte sich nach Applikation von 125 mg Flugasche auf eine Fläche von 50 cm2 innerhalb von 12 Tagen von 6 % in der Kontrolle auf 14 %. Eine mit Diatomeenerde zur Positivkontrolle durchgeführte Versuchsreihe hatte hingegen bei gleich hoher Dosierung eine 100 %ige Abtötung aller adulten Kornkäfer zur Folge. Starke Pflanzausfälle waren erst bei einem komplett aus Flugasche bestehendem Substrat zu verzeichnen. Nur geringfügig waren die Wuchsleistungen der verwendeten Pflanzen ab einem Flugascheanteil von 50 % im Substrat beeinträchtigt.
相似文献
Christian UlrichsEmail: |
479.
Development of two real-time PCR assays for the detection of Mycoplasma hyopneumoniae in clinical samples 总被引:2,自引:0,他引:2
Dubosson CR Conzelmann C Miserez R Boerlin P Frey J Zimmermann W Häni H Kuhnert P 《Veterinary microbiology》2004,102(1-2):55-65
In order to improve the diagnosis of enzootic pneumonia (EP) in pigs two real-time polymerase chain reaction (rtPCR) assays for the detection of Mycoplasma hyopneumoniae in bronchial swabs from lung necropsies were established and validated in parallel. As a gold standard, the current "mosaic diagnosis" was taken, including epidemiological tracing, clinical signs, macro- and histopathological lesions of the lungs and immunofluorescence. One rtPCR is targeting a repeated DNA element of the M. hyopneumoniae genome (REP assay), the other a putative ABC transporter gene (ABC assay). Both assays were shown to be specific for M. hyopneumoniae and did not cross react with other bacteria and mollicutes from pig. With material from pigs of defined EP-negative farms the two assays showed to be 100% specific. When testing lungs from pig farms with EP, the REP assay detected 50% and the ABC assay 90% of the farms as positive. Both tests together detected all positive farms. Within a positive herd the two assays tested similarly with on average over 90% of the lung samples analysed from a single farm showing positive scores. A series of samples with suspicion of EP and samples from pigs with diseases other than respiratory taken from current routine diagnostic was assayed. None of the assays showed false positive results. The sensitivities in this sample group were 50% for the REP and 70% for the ABC assays and for both assays together 85%. The two assays run in parallel are therefore a valuable tool for the improvement of the current diagnosis of EP. 相似文献
480.
Kuemmerle JM Auer JA Rademacher N Lischer CJ Bettschart-Wolfensberger R Fürst AE 《Veterinary surgery : VS》2008,37(2):193-200
Objective— To describe short incomplete sagittal fractures of the proximal phalanx (type Ia P1 fractures) in horses not used for racing and report outcome.
Study Design— Retrospective study.
Animals— Horses (n=10) with type Ia P1 fractures.
Methods— Retrieved data of horses with type Ia P1 fractures were signalment, history and results of orthopedic examination. Radiographs were re-evaluated for position and length of the fracture line, presence of osteoarthritis or subchondral cystic lesions (SCL), periosteal new bone formation and subchondral sclerosis. Conservative treatment (n=4) included box confinement for 2 months followed by 1 month of hand walking. Surgical therapy (n=6) consisted of internal fixation by screws inserted in lag fashion in 5 horses. Concurrent SCL were debrided by curettage via a transcortical drilling approach. In 1 horse, only SCL curettage but not internal fixation was performed. Outcome was assessed on a clinical and radiographic follow-up examination in all horses.
Results— Mean follow-up time was 27 months (median, 13.5 months; range, 9 months to 9 years). All horses treated with internal fixation were sound at follow-up and had radiographic fracture healing. Of the 4 horses managed conservatively, 3 remained lame and only 1 horse had radiographic evidence of fracture healing. Catastrophic fracture propagation occurred in 2 horses not treated by internal fixation, 20 and 30 months after diagnosis, respectively.
Conclusions— Horses with a type Ia P1 fracture treated surgically had a better outcome than those managed conservatively and lack of fracture healing seemingly increases the risk of later catastrophic fracture.
Clinical Relevance— Surgical repair of type Ia P1 fractures should be considered to optimize healing and return to athletic use. 相似文献
Study Design— Retrospective study.
Animals— Horses (n=10) with type Ia P1 fractures.
Methods— Retrieved data of horses with type Ia P1 fractures were signalment, history and results of orthopedic examination. Radiographs were re-evaluated for position and length of the fracture line, presence of osteoarthritis or subchondral cystic lesions (SCL), periosteal new bone formation and subchondral sclerosis. Conservative treatment (n=4) included box confinement for 2 months followed by 1 month of hand walking. Surgical therapy (n=6) consisted of internal fixation by screws inserted in lag fashion in 5 horses. Concurrent SCL were debrided by curettage via a transcortical drilling approach. In 1 horse, only SCL curettage but not internal fixation was performed. Outcome was assessed on a clinical and radiographic follow-up examination in all horses.
Results— Mean follow-up time was 27 months (median, 13.5 months; range, 9 months to 9 years). All horses treated with internal fixation were sound at follow-up and had radiographic fracture healing. Of the 4 horses managed conservatively, 3 remained lame and only 1 horse had radiographic evidence of fracture healing. Catastrophic fracture propagation occurred in 2 horses not treated by internal fixation, 20 and 30 months after diagnosis, respectively.
Conclusions— Horses with a type Ia P1 fracture treated surgically had a better outcome than those managed conservatively and lack of fracture healing seemingly increases the risk of later catastrophic fracture.
Clinical Relevance— Surgical repair of type Ia P1 fractures should be considered to optimize healing and return to athletic use. 相似文献