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71.
R W Schevitz M A Navia D A Bantz G Cornick J J Rosa M D Rosa P B Sigler 《Science (New York, N.Y.)》1972,177(47):429-431
An isomorphous osmium derivative of crystalline yeast initiator transfer RNA has been prepared and interpreted to 6-angstrom resolution. The coordinates of the heavy atoms have been determined by Patterson and "direct" methods applied to the difference coefficients of the centric projections, followed by least-squares refinement. There is one dominant site per asymmetric unit, consistent with the finding by neutron-activation analysis that there is approximately one osmium atom per molecule of transfer RNA. The osmium derivative appears to be a normal substrate for enzymatic aminoacylation. 相似文献
72.
Cimino G DE Rosa S DE Stefano S Sodano G Villani G 《Science (New York, N.Y.)》1983,219(4589):1237-1238
A biosynthetic experiment with mevalonic acid labeled with carbon-14 showed that the nudibranch Dendrodoris limbata elaborates polygodial, a sesquiterpenoid dialdehyde stored in the mantle, which constitutes its chemical defense against predators. Previously described nudibranchs drew defensive chemicals from their preys. 相似文献
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Gelfand MJ Raver JL Nishii L Leslie LM Lun J Lim BC Duan L Almaliach A Ang S Arnadottir J Aycan Z Boehnke K Boski P Cabecinhas R Chan D Chhokar J D'Amato A Ferrer M Fischlmayr IC Fischer R Fülöp M Georgas J Kashima ES Kashima Y Kim K Lempereur A Marquez P Othman R Overlaet B Panagiotopoulou P Peltzer K Perez-Florizno LR Ponomarenko L Realo A Schei V Schmitt M Smith PB Soomro N Szabo E Taveesin N Toyama M Van de Vliert E Vohra N Ward C Yamaguchi S 《Science (New York, N.Y.)》2011,332(6033):1100-1104
With data from 33 nations, we illustrate the differences between cultures that are tight (have many strong norms and a low tolerance of deviant behavior) versus loose (have weak social norms and a high tolerance of deviant behavior). Tightness-looseness is part of a complex, loosely integrated multilevel system that comprises distal ecological and historical threats (e.g., high population density, resource scarcity, a history of territorial conflict, and disease and environmental threats), broad versus narrow socialization in societal institutions (e.g., autocracy, media regulations), the strength of everyday recurring situations, and micro-level psychological affordances (e.g., prevention self-guides, high regulatory strength, need for structure). This research advances knowledge that can foster cross-cultural understanding in a world of increasing global interdependence and has implications for modeling cultural change. 相似文献
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Jaime A. Ocampo-Hernández Patricia Tamez-Guerra Samuel Pineda Fernando Tamayo-Mejía Ariel Guzmán-Franco José I. Figueroa de la Rosa Ana Mabel Martínez 《Journal of pest science》2011,84(4):471-477
Entomopathogenic fungi represent excellent candidates for biological insecticides. Among the many entomopathogenic fungi, Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) is one of the most promising species. Here, we report the results of infection studies performed using four B. bassiana native isolates (Bb37, Bb38, Bb40, and Bb45) compared with the commercial product Mycotrol® (strain GHA) on adult Mexican bean beetle Epilachna varivestis Mulsant (Coleoptera: Coccinellidae), one of the most important pests of bean production in Mexico. First, single concentration (1 × 108 conidia mL?1) assays were carried out using all isolates applied using an immersion method. Examinations at 10 days after inoculation indicated that isolates Bb37, Bb38, and Bb40 significantly reduced adult survival, causing 60–75% mortality compared to the commercial strain GHA (33%) and control (29%). Second, using two selected isolates (Bb37 and Bb40), the mean lethal concentration values (LC50) were estimated for third instar larvae and adult E. varivestis. The LC50 values for Bb37 and Bb40 isolates decreased 5.26-fold and 3.19-fold, respectively, in third instars compared with adults. However, such difference for Bb40 isolate was not significant. Finally, an experiment, to compare the median survival time (MST) values between third instar and adult E. varivestis, was conducted using Bb37 and Bb40 at 1 × 109 conidia mL?1. MST values were significantly reduced against larvae (87 and 100 h) compared with adults (130 and 134 h) by Bb37 and Bb40, respectively. We conclude that native isolates of B. bassiana represent an important alternative for the control of E. varivestis. However, to demonstrate its effectiveness under field conditions, detailed studies are needed. 相似文献
79.
Padilha ST Steagall PV Monteiro BP Kahvegian MA Ubukata R Rodrigues EO Rosa AL Aguiar AJ 《Journal of Feline Medicine and Surgery》2011,13(10):738-743
Sixteen cats were used to compare the cardiovascular and anesthetic effects of remifentanil (REMI) or alfentanil (ALF) in propofol-anesthetized cats undergoing ovariohysterectomy. After premedication with acepromazine, anesthesia was induced and maintained with a constant rate infusion of propofol (0.3 mg/kg/min). REMI or ALF infusions were administered simultaneously with propofol. Heart rate (HR), systolic arterial pressure (SAP), pulse oximetry (SpO(2)), rectal temperature (RT), and response to surgical stimulation were recorded at predefined time points during anesthesia. Data [mean±standard deviation (SD)] were analyzed by analysis of variance (ANOVA) for repeated measures followed by a Dunnett's test and Student t-test (P<0.05). SAP was significantly lower in ALF group than in REMI group. Extubation time was significantly shorter in REMI than in ALF group. Overall infusion rate of REMI and ALF was 0.24±0.05 μg/kg/min and 0.97±0.22 μg/kg/min, respectively. The combination of propofol and REMI or ALF provided satisfactory anesthesia in cats undergoing ovariohysterectomy. 相似文献
80.
Piérri Spolti Luana Schneider Rosa M. V. Sanhueza Jean C. Batzer Mark L. Gleason Emerson Medeiros Del Ponte 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(1):21-29
Sooty blotch and flyspeck is caused by numerous species of fungi that colonize the surface of apple fruit and thereby lower
its market value. Although this disease poses a substantial threat to apple growers’ profitability in some regions, reliable
and cost-effective methods for epidemiological and disease control studies have not been validated, nor are they widely available.
We modified a standard area diagram to aid sooty blotch and flyspeck severity assessments and quantified its impact on accuracy
and precision of visual estimates. Samples of ‘Fuji’ and ‘Mutsu’ fruit were photographed both from the top and laterally.
Severity was assessed from a sub-sample of 160 images using image analysis software. Validation of the diagram was performed
by eight raters who independently assessed severity in two series of selected images representing the lateral view and the
top view, initially unaided and subsequently with the aid of the scale. Severity estimates ranged from 0.4% to 98% (most fruit
had <10% severity). Accuracy and precision of the estimates were significantly improved when using the diagrammatic scale;
concordance correlation coefficient values increased from 0.81 to 0.95. A strong tendency to underestimate severity for the
mid-range to high levels was minimized when using the aid, which also improved reproducibility of the estimates among raters.
In addition to strengthening evidence that a standard area diagram can be used reliably in sooty blotch and flyspeck studies,
we expanded its application to disease assessment in the peduncle region, which enhances the usefulness of the method for
evaluating efficacy of management practices. 相似文献