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Zhou M Morgner N Barrera NP Politis A Isaacson SC Matak-Vinković D Murata T Bernal RA Stock D Robinson CV 《Science (New York, N.Y.)》2011,334(6054):380-385
The ability of electrospray to propel large viruses into a mass spectrometer is established and is rationalized by analogy to the atmospheric transmission of the common cold. Much less clear is the fate of membrane-embedded molecular machines in the gas phase. Here we show that rotary adenosine triphosphatases (ATPases)/synthases from Thermus thermophilus and Enterococcus hirae can be maintained intact with membrane and soluble subunit interactions preserved in vacuum. Mass spectra reveal subunit stoichiometries and the identity of tightly bound lipids within the membrane rotors. Moreover, subcomplexes formed in solution and gas phases reveal the regulatory effects of nucleotide binding on both ATP hydrolysis and proton translocation. Consequently, we can link specific lipid and nucleotide binding with distinct regulatory roles. 相似文献
123.
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
127.
Veronesi F Diaferia M Viola O Fioretti DP 《Veterinary journal (London, England : 1997)》2011,190(2):296-299
The long-term effects of a toltrazuril treatment against natural Eimeria bovis and/or Eimeria zuernii infections were investigated in comparison with diclazuril and untreated controls on two dairy (Italian Friesian breed) and two beef (Chianina breed) farms. At each trial site, 30 calves were allocated into three groups of 10 calves each: T (treated with toltrazuril), D (treated with diclazuril) and C (left untreated). For 40 weeks post-treatment, the calves were weighed and examined clinically and parasitologically. The oocyst counts as well as the number of scour days were significantly lower in the T group than in the D and C groups. Final bodyweights and body condition scores of the T group exceeded those of groups C and D. The results confirmed that toltrazuril was highly efficacious, safe and provided productive benefits in dairy and beef calves. 相似文献
128.
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
129.
Objective To determine corneal sensitivity in 20 healthy adult alpacas (40 eyes) in order to establish reference values. Design Prospective study. Animals Twenty healthy, adult alpacas. Procedures Corneal sensitivity was determined by the corneal touch threshold (CTT) using a Cochet‐Bonnet esthesiometer. Five different regions of the cornea were evaluated (nasal, ventral, lateral, dorsal, and central). Results Corneal touch threshold values (in mm filament length) obtained from five corneal regions demonstrated varying corneal sensitivities. The central region (34.5 ± 7.1 mm) was the most sensitive, followed by the ventral (29.5 ± 7.2 mm), medial (29.3 ± 7.3 mm), dorsal (25.6 ± 6.3 mm), and lateral (21.8 ± 5.7 mm) regions. All pairwise comparisons of regional differences were statistically significant (P < 0.05), except for the comparison between the ventral and medial regions (P = 0.88). Evaluation of the CCT while controlling for age (2–5 years vs. 6–10 years) demonstrated an increased CTT with an increasing age for the central, ventral, medial and lateral regions. A decrease in the CTT of the dorsal region was noted with increasing age. Conclusion and Clinical Relevance Corneal touch threshold values in 40 eyes of 20 healthy adult alpacas were determined using a Cochet‐Bonnet esthesiometer. This study demonstrated the central corneal region to be most sensitive. Values obtained may serve as reference values in subsequent studies. 相似文献
130.
Danail Takov Danail Doychev Andreas Linde Slavimira Draganova Daniela Pilarska 《Phytoparasitica》2011,39(4):343-352
The occurrence and prevalence of bark beetle pathogens in forest stands in Bulgaria were investigated in 944 specimens belonging
to 21 bark beetle species. Protozoa, microsporidia, fungi and nematodes occurred in 19 of all investigated species. The infections
were found in the gut (nematodes, gregarines, microsporidia), gonads (microsporidia) and hemolymph (nematodes) of the infected
insects. Protozoan species (Gregarina typographi, Gregarina spp.) were detected in eight bark beetle species. Morphometric data about G. typographi and Gregarina spp. are presented. The prevalence of the gregarines varied between 1.4% and 64.2%. Microsporidia of the genera Nosema and Chytridiopsis were revealed in three bark beetle species. The prevalence of microsporidia ranged between 1.5% and 11.8%. This is the first report of a microsporidium in Taphrorychus villifrons and of gregarines in T. villifrons, Pityogenes bistridentatus, P. conjunctus, and Orthotomicus erosus. The fungus Beauveria bassiana was found in 3.4% of Hylurgops palliatus specimens. Nematodes (in gut and haemolymph) were revealed in 19 bark beetle species and their prevalence varied between
10% and 98.5%. 相似文献