To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Giant ragweed is a highly competitive weed that continually threatens crop production systems due to evolved resistance to acetolactate synthase–inhibiting herbicides (ALS-R) and glyphosate (GR). Two biotypes of GR giant ragweed exist and are differentiated by their response to glyphosate, termed here as rapid response (RR) and non–rapid response (NRR). A comparison of data from surveys of Indiana crop fields done in 2006 and 2014 showed that GR giant ragweed has spread from 15% to 39% of Indiana counties and the NRR biotype is the most prevalent. A TaqMan® single-nucleotide polymorphism genotyping assay was developed to identify ALS-R populations and revealed 47% of GR populations to be ALS-R as well. The magnitude of glyphosate resistance for NRR populations was 4.6 and 5.9 based on GR50 and LD50 estimates, respectively. For RR populations, these values were 7.8 to 9.2 for GR50 estimates and 19.3 to 22.3 for LD50 estimates. A novel use of the Imaging-PAM fluorometer was developed to discriminate RR plants by assessing photosystem II quantum yield across the entire leaf surface. H2O2 generation in leaves of glyphosate-treated plants was also measured by 3,3′-diaminobenzidine staining and quantified using imagery analysis software. Results show photo-oxidative stress of mature leaves is far greater and occurs more rapidly following glyphosate treatment in RR plants compared with NRR and glyphosate-susceptible plants and is positively associated with glyphosate dose. These results suggest that under continued glyphosate selection pressure, the RR biotype may surpass the NRR biotype as the predominant form of GR giant ragweed in Indiana due to a higher level of glyphosate resistance. Moreover, the differential photo-oxidative stress patterns in response to glyphosate provide evidence of different mechanisms of resistance present in RR and NRR biotypes.
We have serendipitously discovered that the WN+O binary Br 40a in the LMC is surrounded by a remarkable high excitation nebula, showing extended, narrow emission lines of HeII. This prompted us to make a systematic search for similar high excitation nebulae around other WR stars in the Magellanic Clouds. This survey revealed a second even more extreme example surrounding the WN+O binary AB-7 in the SMC, and one other marginal detection AB-5 (SMC). The detection of nebular HeII emission implies that these WN stars emit a much harder UV spectrum than is traditionally expected. For each of these nebulae we have taken narrow band CCD images at the CTIO 0.9-m telescope, and have obtained spectrophotometry with the 2D-Frutti photon counting detector on the CTIO 1.0-m telescope.
The new mineral hansesmarkite (IMA2015-067),
was discovered at the AS Granit larvikite quarry in Tvedalen, Larvik,
Vestfold, Norway. Hansesmarkite forms faintly yellow crystals up to 0.3 mm
or thin coatingsin patches on gonnardite. Hansesmarkite is biaxial (+) with
refractive indices (white light): α = 1.683(2), β = 1.698(2) and γ =
1.745(3); 2V(meas.) = 60.7(6)° and 2V(calc.) = 60.3°.
The mineral exhibits moderate dispersion (r >
v)and is pleochroic with X (almost
colourless) < Y ( pale yellow) <<
Z (orangey yellow). The optical orientation is
X ^ c = 20°, Y ^
b = 16° and Z ^ a =
5°. The empirical formula based on five electron probemicroanalyses and
calculated based on Nb = 6 apfu is
with H2O determined from the structure solution.The mineral is
triclinic, P1, with a = 9.081(4),
b = 9.982(8), c = 10.60(1) Å, α =
111.07(8), β = 101.15(6), γ = 99.39(5)°, V = 850.8(13) Å3
and Z = 1. The structure was solved at 120 K because of
thermalinstability of the mineral and refined to R1 = 2.50% for Fo > 4σ. The strongest reflections in the x-ray diffraction
diagram are: [dobs. in Å (I)(hkl)]
9.282(36)(001), 8.610(100)(100, 011), 3.257(30)(031, 131)and 3.058(18)(130,
212). Hansesmarkite is the third naturally occurring hexaniobate in which
six edge-sharing Nb-octahedra form the Lindqvist ion. These are linked via
Mn-octahedra forming rods along  and Ca is located between the rods,
creating a three dimensional structure via hydrogen bonds.
Leptomeningeal metastasis is a serious complication of systemic cancer commonly occurring in later disease stages which affects approximately 10% of patients with solid tumors. The risk is highest for patients with lung cancer, melanoma and breast cancer. Survival at one year is in the range of 10%. Cerebrospinal fluid analysis and magnetic resonance imaging are the most important diagnostic measures. Treatment recommendations vary by primary tumor and pattern of disease, that is, e.g., the absence or presence of concurrent systemic or solid brain metastasis. To explore the current practice of diagnosing and treating leptomeningeal metastasis across Europe, a web-based survey was sent to members of the European Association of Neuro-Oncology (EANO) and the Brain Tumor Group of the European Organisation for Research and Treatment of Cancer (EORTC) in April 2016 which contains 24 questions on current practice patterns as well as 8 case presentations. The results of this survey will be presented for the first time. They shall serve as the basis for treatment recommendations for this complication of systemic cancer that reflects current knowledge as well as current practice.
We have obtained high-dispersion, long-slit echelle spectra at closely spaced intervals across the face of the bipolar planetary nebulae NGC 2440, NGC 6302 and Mz-3. Deep monochromatic images of these objects in lines from high (HeII, [OIII]), intermediate (HI, [OII]) and low ([NII], [SII]) excitation species have also been acquired. Taken together, these data permit us to construct self-consistent spatio-kinematic models of these nebulae and to investigate the spatial variations of excitation conditions within them.
Long slit, high and low resolution, spectrograms of this object were obtained using the telescopes at CTIO. From the [N II] λ6584 line in the high resolution spectrum, we obtained a radial velocity difference between the front and back expanding shells at the center of the nebula of 56 km s−1 corresponding to an expansion velocity of 28 km s−1, From the low resolution spectra we found [S II] λλ6717/6731 line ratios indicating densities between 500 cm−3 and less than 200 cm−3. The temperature sensitive line ratios of [O III] and [N II] were not well determined due to the weakness of the λ4363 and λ5733 lines. A ionization structure is clearly seen with radial distance to the central star which shows that the inner shell (A2, A4, B2, B4) is not a projection of the outer one but a separate structure.
A segment of the debate surrounding the commercialization and use of glyphosate-resistant (GR) crops focuses on the theory that the implementation of these traits is an extension of the intensification of agriculture that will further erode the biodiversity of agricultural landscapes. A large field-scale study was initiated in 2006 in the United States on 156 different field sites with a minimum 3-yr history of GR-corn, -cotton or -soybean in the cropping system. The impact of cropping system, crop rotation, frequency of using the GR crop trait, and several categorical variables on seedbank weed population density and diversity was analyzed. The parameters of total weed population density of all species in the seedbank, species richness, Shannon's H′ and evenness were not affected by any management treatment. The similarity between the seedbank and aboveground weed community was more strongly related to location than management; previous year's crops and cropping systems were also important while GR trait rotation was not. The composition of the weed flora was more strongly related to location (geography) than any other parameter. The diversity of weed flora in agricultural sites with a history of GR crop production can be influenced by several factors relating to the specific method in which the GR trait is integrated (cropping system, crop rotation, GR trait rotation), the specific weed species, and the geographical location. Continuous GR crop, compared to fields with other cropping systems, only had greater species diversity (species richness) of some life forms, i.e., biennials, winter annuals, and prostrate weeds. Overall diversity was related to geography and not cropping system. These results justify further research to clarify the complexities of crops grown with herbicide-resistance traits to provide a more complete characterization of their culture and local adaptation to the weed seedbank.
An a posteriori granddaughter design was applied to estimate quantitative trait loci genotypes of sires with many sons in the US Holstein population. The results of this analysis can be used to determine concordance between specific polymorphisms and segregating quantitative trait loci. Determination of the actual polymorphisms responsible for observed genetic variation should increase the accuracy of genomic evaluations and rates of genetic gain. A total of 52 grandsire families, each with ⩾100 genotyped sons with genetic evaluations based on progeny tests, were analyzed for 33 traits (milk, fat and protein yields; fat and protein percentages; somatic cell score (SCS); productive life; daughter pregnancy rate; heifer and cow conception rates; service-sire and daughter calving ease; service-sire and daughter stillbirth rates; 18 conformation traits; and net merit). Of 617 haplotype segments spanning the entire bovine genome and each including ~5×106 bp, 5 cM and 50 genes, 608 autosomal segments were analyzed. A total of 19 335 unique haplotypes were found among the 52 grandsires. There were a total of 133 chromosomal segment-by-trait combinations, for which the nominal probability of significance for the haplotype effect was <10−8, which corresponds to genome-wide significance of <10−4. The number of chromosomal regions that met this criterion by trait ranged from one for rear legs (rear view) to seven for net merit. For each of the putative quantitative trait loci, at least one grandsire family had a within-family contrast with a t-value of >3. Confidence intervals (CIs) were estimated by the nonparametric bootstrap for the largest effect for each of nine traits. The bootstrap distribution generated by 100 samples was bimodal only for net merit, which had the widest 90% CI (eight haplotype segments). This may be due to the fact that net merit is a composite trait. For all other chromosomes, the CI spanned less than a third of the chromosome. The narrowest CI (a single haplotype segment) was found for SCS. It is likely that analysis by more advanced methods could further reduce CIs at least by half. These results can be used as a first step to determine the actual polymorphisms responsible for observed quantitative variation in dairy cattle.
The purpose of this study was to evaluate the effect of temperature and different levels of available phosphorus (aP) on the expression of nine genes encoding electron transport chain proteins in the Longissimus dorsi (LD) muscle of pigs. Two trials were carried out using 48 high-lean growth pigs from two different growth phases: from 15 to 30 kg (phase 1) and from 30 to 60 kg (phase 2). Pigs from growth phase 1 were fed with three different levels of dietary aP (0.107%, 0.321% or 0.535%) and submitted either to a thermoneutral (24°C and RH at 76%) or to a heat stress (34°C and RH at 70%) environment. Pigs from growth phase 2 were fed with three different levels of dietary aP (0.116%, 0.306% or 0.496%) and submitted either to a thermoneutral (22ºC and RH at 77%) or to a heat stress (32ºC and RH at 73%) environment. Heat stress decreased (P<0.001) average daily feed intake at both growth phases. At 24°C, pigs in phase 1 fed the 0.321% aP diet had greater average daily gain and feed conversion (P<0.05) than those fed the 0.107% or 0.535% while, at 34°C pigs fed the 0.535% aP had the best performance (P<0.05). Pigs from phase 2 fed the 0.306% aP had best performance in both thermal environments. Gene expression profile was analyzed by quantitative real-time polymerase chain reaction. Irrespective of growing phase, the expression of six genes was lower (P<0.05) at high temperature than at thermoneutrality. The lower expression of these genes under high temperatures evidences the effects of heat stress by decreasing oxidative metabolism, through adaptive physiological mechanisms in order to reduce heat production. In pigs from phase 1, six genes were differentially expressed across aP levels (P<0.05) in the thermoneutral and one gene in the heat stress. In pigs from phase 2, two genes were differentially expressed across aP levels (P<0.05) in both thermal environments. These data revealed strong evidence that phosphorus and thermal environments are key factors to regulate oxidative phosphorylation with direct implications on animal performance.
A segment of the debate surrounding the commercialization of genetically engineered (GE) crops, such as glyphosate-resistant (GR) crops, focuses on the theory that implementation of these traits is an extension of the intensification of agriculture that will further erode the biodiversity of agricultural landscapes. A large field-scale study was conducted in 2006 in the United States on 156 different field sites with a minimum 3-yr history of GR corn, cotton, or soybean in the cropping system. The impact of cropping system, crop rotation, frequency of using the GR crop trait, and several categorical variables on emerged weed density and diversity was analyzed. Species richness, evenness, Shannon's H′, proportion of forbs, erect growth habit, and C3 species diversity were all greater in agricultural sites that lacked crop rotation or were in a continuous GR crop system. Rotating between two GR crops (e.g., corn and soybean) or rotating to a non-GR crop resulted in less weed diversity than a continuous GR crop. The composition of the weed flora was more strongly related to location (geography) than any other parameter. The diversity of weed flora in agricultural sites with a history of GR crop production can be influenced by several factors relating to the specific method in which the GR trait is integrated (cropping system, crop rotation, GR trait rotation), the specific weed species, and the geographical location. The finding that fields with continuous GR crops demonstrated greater weed diversity is contrary to arguments opposing the use of GE crops. These results justify further research to clarify the complexities of crops grown with herbicide-resistance traits, or more broadly, GE crops, to provide a more complete characterization of their culture and local adaptation.
We have investigated structural and magnetic properties of CoPt alloy films with strong perpendicular magnetic anisotropy in the thickness range between 100Å and 400A. From a detailed x-ray analysis we find highly (111) -textured CoPt Microcrystal-lites in all samples. STM studies reveal a granular topography with grain diameters of up to 250Å. Measurements of hysteresis loops yield a saturation field which increases with thickness, and which is consistent with a freely mobile domain Model. Brillouin light scattering measurements of the frequencies of the surface and standing spin wave modes yield a bulk exchange constant, which is strongly dependent on the Pt content.
High resolution Kerr Microscopy has been used to study newly developed Co25Pt75 alloy films with perpendicular magnetic anisotropy. In particular, the dynamics of magnetization reversal processes wase investigated by means of time resolved domain pattern analysis. Domain wall motion dominated magnetization reversal as well as nucleation dominated processes were observed. Magnetic aftereffect phenomena were confirmed by relaxation measurements of magnetic domains. The fractal dimension of the observed domains is correlated to the macroscopic coercivity determined from hysteresis loop Measurements.
We present a comparative in situ RHEED and Polar Magneto-optic Kerr Effect study of the first stages of the growth of a Au overlayer on top of a (111) Co ultrathin film. Drastic behaviours are evidenced on the RHEED diagram, Magnetic anisotropy and coercive force, around 1,5 ML of Au coverage.
In 2010, a grower survey was administered to 1,299 growers in 22 states to determine changes in weed management in the United States from 2006 to 2009. The majority of growers had not changed weed management practices in the previous 3 yr; however, 75% reported using weed management practices targeted at glyphosate-resistant (GR) weeds. Growers were asked to rate their efforts at controlling GR weeds and rate the effectiveness of various practices for controlling/preventing GR weeds regardless of whether they were personally using them. Using the herbicide labeled rate, scouting fields, and rotating crops were among the practices considered by growers as most effective in managing GR weeds. Sixty-seven percent of growers reported effective management of GR weeds. Between the 2005 and 2010 Benchmark surveys, the frequency of growers using specific actions to manage GR weeds increased markedly. Although the relative effectiveness of practices, as perceived by growers, remained the same, the effectiveness rating of tillage and the use of residual and POST herbicides increased.
Approximately 1,300 growers from 22 states were surveyed during 2010 to determine herbicide use. Cropping systems included continuous glyphosate-resistant corn, cotton, and soybean, and various combinations of these crops and rotations with non–glyphosate-resistant crops. The most commonly used herbicide for both fall and spring applications was glyphosate followed by synthetic auxin herbicides. Herbicide application in spring was favored over application in the fall. The percentage of growers in a glyphosate-only system was as high as 69% for some cropping systems. Excluding glyphosate, the most frequently used herbicides included photosystem II, mitotic, and protoporphyrinogen oxidase inhibitors. A higher percentage of growers integrated herbicides other than glyphosate during 2010 compared with 2005. Extensive educational efforts have promoted resistance management by increasing the diversity of herbicides in glyphosate-resistant cropping systems. However, a considerable percentage of growers continued use of only glyphosate from the period of 2005 to 2010, and this practice most likely will continue to exert a high level of selection for evolved glyphosate-resistant weed species.
Almost 1,650 corn, cotton, and soybean growers in 22 states participated in a 2010 telephone survey to determine their attitudes with regard to which weed species were most problematic in glyphosate-resistant (GR) crop production systems for corn, cotton, and soybean. The survey is a follow-up to a previous 2005 to 2006 survey that utilized a smaller set of growers from fewer states. In general, growers continued to estimate weed populations as low and few challenges have been created following adoption of GR cropping systems. Pigweed and foxtail species were dominant overall, whereas other species were more commodity and state specific. Corn, cotton, and soybean growers cited velvetleaf, annual morningglory, and waterhemp, respectively, as predominant weeds. Growers in the South region were more likely to report pigweed and waterhemp (Amaranthus spp.), whereas growers in the East and West reported horseweed. When growers were asked with which GR weeds they had experienced personally, horseweed was reported in all regions, but growers in the South more frequently reported pigweed, whereas growers in the East and West regions more frequently reported waterhemp. Comparisons with the previous 2005 survey indicated that more growers believed they were experiencing GR weeds and were more aware of specific examples in their state. In particular, the Amaranthus complex was of greatest concern in continuously cropped soybean and cotton.
A 2010 survey of 1,299 corn, cotton, and soybean growers was conducted to determine their attitudes and awareness regarding glyphosate-resistant (GR) weeds and resultant implications on weed management practices. An additional 350 growers included in the current study participated in a 2005 survey, and these answers were compared across time so that cross-sectional and longitudinal comparisons of responses could be made. Most growers surveyed in 2010 were aware of the potential for weeds to evolve resistance to glyphosate; however, many growers were not aware of glyphosate resistance in specific weeds in their county or state. Growers in the South were different from growers in other geographic regions and were significantly more aware of local cases of GR weeds. Awareness of GR weeds did not increase appreciably from 2005 to 2010, but the percentage who reported GR weeds as problematic was significantly higher. Grower reports of GR weeds on-farm in 2010 were up considerably from 2005, with growers in the South reporting significantly more instances than growers in other regions. Growers in the South were also more likely to consider glyphosate resistance a serious problem. Overall, 30% of growers did not consider GR weeds to be a problem. It appears that most growers received information about glyphosate resistance from farm publications, although in the South this percentage was less than for other geographic regions. Growers in the South received more information from universities and extension sources.
Field studies were conducted to determine the response of sublethal glyphosate and dicamba doses to processing tomato flowering loss and marketable yield. Dose–response studies for both herbicides were conducted on four commercial processing tomato lines (two different lines within each study) and plants were sprayed at either the vegetative stage or the early bloom stage. Both glyphosate and dicamba caused higher yield losses when sprayed at the early bloom stage. A 25% yield loss was observed with 8.5 and 7.5 g ae ha−1 for glyphosate and dicamba, respectively, at the early bloom stage and 43.9 and 11.9 g ae ha−1 for glyphosate and dicamba, respectively, at the early vegetative stage. Overall, these tomato cultivars were more sensitive to dicamba than to glyphosate. We conclude that glyphosate and dicamba drift could have serious implications on tomato yields especially if the drift occurs during flowering.
Introduction, Mandeep K. Dhami, Anne Schlottmann, and Michael R. Waldmann
In conclusion, rather than present a summary of the preceding chapters, we invited nine eminent past presidents of the Society for Judgment and Decision Making (SJDM) to provide personal perspectives on the concept of JDM as a dynamic skill. These scholars were not asked to comment on the chapters in this book, but rather to highlight their personal points of contact with the notion of JDM as a dynamic skill. The following perspectives offer historical accounts, and also point to future lines of research.
Shanteau describes how over the years he has highlighted the importance of training and skill acquisition in JDM, but feels “blue” that this view has not been more popular. Wallsten remembers the benefits of learning for JDM performance found in a study that he conducted 30 years ago, and confesses that he has only recently begun to revisit this important finding. Fischhoff points out that a sound understanding of the normative implications of tasks has laid a better foundation for the study of dynamically changing skills, especially in development. Levin and colleagues provide useful examples of their research on the developmental and neurological bases of JDM skills. Reyna highlights how her fuzzy trace theory taps into JDM processes that develop over time and experience, has neurological correlates, and may be evolutionarily adaptive. Baron reveals how he now finds himself in search of the developmental origins of the types of moral heuristics and biases that he has studied during his career. Hogarth shares three steps he has developed during decades of teaching decision making that can help people make better decisions. Klayman reveals that despite decades of studying learning and development of JDM, he still seeks a greater understanding of how decision makers “get that way.” Finally, Birnbaum points to the methodological factors that have limited our understanding of JDM as a skill, and presents a challenge for future researchers: to explain how and why JDM skills change. Overall, the following perspectives provide a rare glimpse of the personalized views of those who have made significant contributions to the field of human JDM.