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Some children are more affected by specific family environments than others, as a function of differences in their genetic make-up. However, longitudinal studies of genetic moderation of parenting effects during early childhood have not been conducted. We examined developmental profiles of child behavior problems between 18 months and age 8 in a longitudinal parent–offspring sample of 361 adopted children. In toddlerhood (18 months), observed structured parenting indexed parental guidance in service of task goals. Biological parent psychopathology served as an index of genetic influences on children’s behavior problems. Four profiles of child behavior problems were identified: low stable (11%), average stable (50%), higher stable (29%), and high increasing (11%). A multinominal logistic regression analysis indicated a genetically moderated effect of structured parenting, such that for children whose biological mother had higher psychopathology, the odds of the child being in the low stable group increased as structured parenting increased. Conversely, for children whose biological mother had lower psychopathology, the odds of being in the low stable group was reduced when structured parenting increased. Results suggest that increasing structured parenting is an effective strategy for children at higher genetic risk for psychopathology, but may be detrimental for those at lower genetic risk.
A chloroacetamide herbicide by application timing factorial experiment was conducted in 2017 and 2018 in Mississippi to investigate chloroacetamide use in a dicamba-based Palmer amaranth management program in cotton production. Herbicides used were S-metolachlor or acetochlor, and application timings were preemergence, preemergence followed by (fb) early postemergence, preemergence fb late postemergence, early postemergence alone, late postemergence alone, and early postemergence fb late postemergence. Dicamba was included in all preemergence applications, and dicamba plus glyphosate was included with all postemergence applications. Differences in cotton and weed response due to chloroacetamide type were minimal, and cotton injury at 14 d after late postemergence application was less than 10% for all application timings. Late-season weed control was reduced up to 30% and 53% if chloroacetamide application occurred preemergence or late postemergence only, respectively. Late-season weed densities were minimized if multiple applications were used instead of a single application. Cotton height was reduced by up to 23% if a single application was made late postemergence relative to other application timings. Chloroacetamide application at any timing except preemergence alone minimized late-season weed biomass. Yield was maximized by any treatment involving multiple applications or early postemergence alone, whereas applications preemergence or late postemergence alone resulted in up to 56% and 27% yield losses, respectively. While no yield loss was reported by delaying the first of sequential applications until early postemergence, forgoing a preemergence application is not advisable given the multiple factors that may delay timely postemergence applications such as inclement weather.
Surface albedo typically dominates the mass balance of mountain glaciers, though long-term trends and patterns of glacier albedo are seldom explored. We calculated broadband shortwave albedo for glaciers in the central Chilean Andes (33–34°S) using end-of-summer Landsat scenes between 1986 and 2020. We found a high inter-annual variability of glacier-wide albedo that is largely a function of the glacier fractional snow-covered area and the total precipitation of the preceding hydrological year (up to 69% of the inter-annual variance explained). Under the 2010–2020 ‘Mega Drought’ period, the mean albedo, regionally averaged ranging from ~0.25–0.5, decreased by −0.05 on average relative to 1986–2009, with the greatest reduction occurring 3500–5000 m a.s.l. In 2020, differences relative to 1986–2009 were −0.14 on average as a result of near-complete absence of late summer snow cover and the driest hydrological year since the Landsat observation period began (~90% reduction of annual precipitation relative to the 1986–2009 period). We found statistically significant, negative trends in glacier ice albedo of up to −0.03 per decade, a trend that would have serious implications for the future water security of the region, because glacier ice melt acts to buffer streamflow shortages under severe drought conditions.
We all now know that the novel coronavirus is anything but a common cold. The pandemic has created many new obligations for all of us, several of which come with serious costs to our quality of life. But in some cases, the guidance and the law are open to a degree of interpretation, leaving us to decide what is the ethical (or unethical but desired) course of action. Because of the high cost of some of the obligations, a conflict of interest can arise between what we want to do and what it is right to do. And so, some people choose to respect only the letter of the law, but not the spirit, or not to respect even the spirit of the guidelines. This paper identifies and describes the new obligations imposed on us all by the pandemic, considers their costs in terms of the good life, and provides an ethical analysis of two personal and two public cases in terms of the letter and spirit of the guidance and legislation.
Systematic reviews and meta-analyses suggest that behaviour change interventions have modest effect sizes, struggle to demonstrate effect in the long term and that there is high heterogeneity between studies. Such interventions take huge effort to design and run for relatively small returns in terms of changes to behaviour.
So why do behaviour change interventions not work and how can we make them more effective? This article offers some ideas about what may underpin the failure of behaviour change interventions. We propose three main reasons that may explain why our current methods of conducting behaviour change interventions struggle to achieve the changes we expect: 1) our current model for testing the efficacy or effectiveness of interventions tends to a mean effect size. This ignores individual differences in response to interventions; 2) our interventions tend to assume that everyone values health in the way we do as health professionals; and 3) the great majority of our interventions focus on addressing cognitions as mechanisms of change. We appeal to people’s logic and rationality rather than recognising that much of what we do and how we behave, including our health behaviours, is governed as much by how we feel and how engaged we are emotionally as it is with what we plan and intend to do.
Drawing on our team’s experience of developing multiple interventions to promote and support health behaviour change with a variety of populations in different global contexts, this article explores strategies with potential to address these issues.
Differential susceptibility theory (DST) posits that individuals differ in their developmental plasticity: some children are highly responsive to both environmental adversity and support, while others are less affected. According to this theory, “plasticity” genes that confer risk for psychopathology in adverse environments may promote superior functioning in supportive environments. We tested DST using a broad measure of child genetic liability (based on birth parent psychopathology), adoptive home environmental variables (e.g., marital warmth, parenting stress, and internalizing symptoms), and measures of child externalizing problems (n = 337) and social competence (n = 330) in 54-month-old adopted children from the Early Growth and Development Study. This adoption design is useful for examining DST because children are placed at birth or shortly thereafter with nongenetically related adoptive parents, naturally disentangling heritable and postnatal environmental effects. We conducted a series of multivariable regression analyses that included Gene × Environment interaction terms and found little evidence of DST; rather, interactions varied depending on the environmental factor of interest, in both significance and shape. Our mixed findings suggest further investigation of DST is warranted before tailoring screening and intervention recommendations to children based on their genetic liability or “sensitivity.”
The Early Growth and Development Study (EGDS) is a prospective adoption study of birth parents, adoptive parents and adopted children (n = 561 adoptees). The original sample has been expanded to include siblings of the EGDS adoptees who were reared by the birth mother and assessed beginning at age 7 years (n = 217 biological children), and additional siblings in both the birth and adoptive family homes, recruited when the adoptees were 8–15 years old (n = 823). The overall study aims are to examine how family, peer and contextual processes affect child and adolescent adjustment, and to examine their interplay (mediation, moderation) with genetic influences. Adoptive and birth parents were originally recruited through adoption agencies located throughout the USA following the birth of a child. Assessments are ongoing and occurred in 9 month’s intervals until the adoptees turned 3 years of age, and in 1 to 2 year intervals thereafter through age 15. Data collection includes the following primary constructs: child temperament, behavior problems, mental health, peer relations, executive functioning, school performance and health; birth and adoptive parent personality characteristics, mental health, health, context, substance use, parenting and marital relations; and the prenatal environment. Findings highlight the power of the adoption design to detect environmental influences on child development and provide evidence of complex interactions and correlations between genetic, prenatal environmental and postnatal environmental influences on a range of child outcomes. The study sample, procedures and an overview of findings are summarized and ongoing assessment activities are described.
To advance research from Dishion and others on associations between parenting and peer problems across childhood, we used a sample of 177 sibling pairs reared apart since birth (because of adoption of one of the siblings) to examine associations between parental hostility and children's peer problems when children were ages 7 and 9.5 years (n = 329 children). We extended conventional cross-lagged parent–peer models by incorporating child inhibitory control as an additional predictor and examining genetic contributions via birth mother psychopathology. Path models indicated a cross-lagged association from parental hostility to later peer problems. When child inhibitory control was included, birth mother internalizing symptoms were associated with poorer child inhibitory control, which was associated with more parental hostility and peer problems. The cross-lagged paths from parental hostility to peer problems were no longer significant in the full model. Multigroup analyses revealed that the path from birth mother internalizing symptoms to child inhibitory control was significantly higher for birth parent–reared children, indicating the possible contribution of passive gene–environment correlation to this association. Exploratory analyses suggested that each child's unique rearing context contributed to his or her inhibitory control and peer behavior. Implications for the development of evidence-based interventions are discussed.
Seven half-day regional listening sessions were held between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide-resistance management. The objective of the listening sessions was to connect with stakeholders and hear their challenges and recommendations for addressing herbicide resistance. The coordinating team hired Strategic Conservation Solutions, LLC, to facilitate all the sessions. They and the coordinating team used in-person meetings, teleconferences, and email to communicate and coordinate the activities leading up to each regional listening session. The agenda was the same across all sessions and included small-group discussions followed by reporting to the full group for discussion. The planning process was the same across all the sessions, although the selection of venue, time of day, and stakeholder participants differed to accommodate the differences among regions. The listening-session format required a great deal of work and flexibility on the part of the coordinating team and regional coordinators. Overall, the participant evaluations from the sessions were positive, with participants expressing appreciation that they were asked for their thoughts on the subject of herbicide resistance. This paper details the methods and processes used to conduct these regional listening sessions and provides an assessment of the strengths and limitations of those processes.
Herbicide resistance is ‘wicked’ in nature; therefore, results of the many educational efforts to encourage diversification of weed control practices in the United States have been mixed. It is clear that we do not sufficiently understand the totality of the grassroots obstacles, concerns, challenges, and specific solutions needed for varied crop production systems. Weed management issues and solutions vary with such variables as management styles, regions, cropping systems, and available or affordable technologies. Therefore, to help the weed science community better understand the needs and ideas of those directly dealing with herbicide resistance, seven half-day regional listening sessions were held across the United States between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide resistance management. The major goals of the sessions were to gain an understanding of stakeholders and their goals and concerns related to herbicide resistance management, to become familiar with regional differences, and to identify decision maker needs to address herbicide resistance. The messages shared by listening-session participants could be summarized by six themes: we need new herbicides; there is no need for more regulation; there is a need for more education, especially for others who were not present; diversity is hard; the agricultural economy makes it difficult to make changes; and we are aware of herbicide resistance but are managing it. The authors concluded that more work is needed to bring a community-wide, interdisciplinary approach to understanding the complexity of managing weeds within the context of the whole farm operation and for communicating the need to address herbicide resistance.
Maternal trauma is a complex risk factor that has been linked to adverse child outcomes, yet the mechanisms underlying this association are not well understood. This study, which included adoptive and biological families, examined the heritable and environmental mechanisms by which maternal trauma and associated depressive symptoms are linked to child internalizing and externalizing behaviors. Path analyses were used to analyze data from 541 adoptive mother–adopted child (AM–AC) dyads and 126 biological mother–biological child (BM–BC) dyads; the two family types were linked through the same biological mother. Rearing mother's trauma was associated with child internalizing and externalizing behaviors in AM–AC and BM–BC dyads, and this association was mediated by rearing mothers’ depressive symptoms, with the exception of biological child externalizing behavior, for which biological mother trauma had a direct influence only. Significant associations between maternal trauma and child behavior in dyads that share only environment (i.e., AM–AC dyads) suggest an environmental mechanism of influence for maternal trauma. Significant associations were also observed between maternal depressive symptoms and child internalizing and externalizing behavior in dyads that were only genetically related, with no shared environment (i.e., BM–AC dyads), suggesting a heritable pathway of influence via maternal depressive symptoms.
In a recent essay, Harker and coauthors stated that considering herbicide resistance as a wicked problem “without clear causes or solutions” ignores what weed scientists know about the biology and management of herbicide-resistant weeds. In this response, we argue that this misrepresents what is meant by “wicked” and that the wicked problem concept is valuable in understanding the multifaceted nature of herbicide resistance as a human-caused phenomenon.
With the shift to earlier maturing soybean cultivars, harvest interference data are needed at low weed densities that will not reduce yield, but may affect soybean quality or harvesting efficiency. Field experiments were conducted in 1995 and 1996 to determine the density of five weeds necessary to warrant desiccation treatments. There were no consistent differences in losses of harvestable soybean due to weed density. Common cocklebur increased foreign material and soybean moisture at a greater rate than did hemp sesbania, ivyleaf morningglory, or redroot pigweed, with sicklepod intermediate among these species. Soybean test weight was reduced by 17, 13, and 59 g/L for each plant/meter of row with redroot pigweed, sicklepod, and common cocklebur, respectively, whereas hemp sesbania and ivyleaf morningglory did not affect test weight. However, all species evaluated increased damaged soybean seeds by 8.2 to 11.1% for each plant/meter of row. Combine speed was not affected substantially by the weed densities evaluated.
The acetolactate synthase-inhibiting herbicides chlorimuron and imazaquin, and the diphenylether herbicides acifluorfen and lactofen, were applied alone and in all possible combinations to the foliage of common cocklebur, pitted morningglory, and prickly sida to evaluate interacting effects on absorption and translocation. The addition of unlabeled acifluorfen to 14C-chlorimuron increased absorption in common cocklebur, pitted morningglory, and prickly sida. Lactofen also increased absorption of 14C-imazaquin in all species. Conversely, imazaquin reduced absorption or translocation of 14C-acifluorfen in common cocklebur or pitted morningglory, respectively. In all species, absorption was lower when unlabeled chlorimuron or imazaquin was combined with 14C-lactofen than when applied alone.
The effects of 1.24 kg ha−1 ammonium sulfate, 5 g ae ha−1 of the isopropylamine salt of imazapyr, and air temperatures of 18, 27, or 35 C at 40 or 100% relative humidity (RH) on the absorption and translocation of the ammonium salt of 14C-imazethapyr applied postemergence to pitted morningglory were evaluated. Absorption of 14C-imazethapyr was greater at 100 than at 40% RH (88 vs. 47%). At 40% RH, absorption was increased to 79% by the addition of ammonium sulfate. At 100% RH absorption was similar with all treatments. Translocation of 14C-imazethapyr applied alone was greater at 100 than at 40% RH (34 vs. 17%). Addition of ammonium sulfate increased translocation at 40% RH but not at 100%. Addition of imazapyr did not affect 14C translocation. Distribution of 14C throughout the plant was more acropetal than basipetal with the greatest distribution at 35 C.
In the field, 14 soft red winter wheat cultivars responded differently to 1.1 kg ai ha–1 diclofop, 1.7 kg ai ha–1 BAY SMY 1500, and 0.42 kg ai ha–1 metribuzin applied POST. Diclofop and metribuzin did not injure any cultivar more than 10% on a silty clay soil. However, BAY SMY 1500 injured ‘Pioneer 2551’ and ‘Coker 983’ 39 and 21%, respectively, in March. All other cultivars were injured less than 10% by BAY SMY 1500. Early injury did not translate into yield loss in the cultivar tolerance study. In an application timing study for Italian ryegrass control, late-season ratings indicated better control with two-leaf applications than with PRE applications for all treatments. Delaying application to the three-tiller stage reduced control with BAY SMY 1500 or metribuzin, but not with diclofop. On the sandier soil at this location, wheat injury with 0.28 or 0.43 kg ha–1 metribuzin or 2.2 kg ha–1 BAY SMY 1500 was sufficient to reduce wheat yield compared with other treatments, despite good Italian ryegrass control.
The effects of 1.24 kg ha-1 ammonium sulfate, 5 g ae ha-1 of the isopropylamine salt of imazapyr, and air temperature of 18, 27, and 35 C at 40 and 100% relative humidity on the phytotoxicity of 35 g ae ha-1 of the ammonium salt of imazethapyr applied postemergence to pitted morningglory were evaluated. Both ammonium sulfate and imazapyr increased imazethapyr phytotoxicity to pitted morningglory. Ammonium sulfate enhanced imazethapyr phytotoxicity the most at 40% whereas imazapyr was most effective at 100% relative humidity. Imazethapyr phytotoxicity was enhanced more by the combination of ammonium sulfate and imazapyr than with either alone regardless of relative humidity. Variations in temperature had little effect on phytotoxicity.
Field experiment were conducted to determine interactions of chlorimuron or imazaquin with fomesafen, lactofen, or acifluorfen on three-leaf and eight-leaf common cocklebur, hemp sesbania, pitted morningglory, and prickly sida. Antagonism was the most common interaction with common cocklebur, and was most severe with chlorimuron combined with fomesafen or acifluorfen, whereas lactofen did not antagonize common cocklebur control. Reductions in control were greater when low rates of chlorimuron were used. On three-leaf prickly sida, control synergistically increased when imazaquin was combined with fomesafen or acifluorfen, but the majority of these combinations were additive on eight-leaf prickly sida. Three-leaf pitted morningglory control synergistically increased when 36 g ai ha–1 imazaquin was combined with 210 g ai ha–1 fomesafen or 110 or 220 g ai ha–1 lactofen. With eight-leaf pitted morningglory, synergism occurred when 2 g ai ha–1 chlorimuron was combined with the high rate of any diphenylether herbicide tested, and when 36 g ha–1 imazaquin was combined with 110 g ha–1 lactofen or 210 g ai ha–1 acifluorfen; however, at higher rates of chlorimuron or imazaquin, several antagonistic interactions occurred. Hemp sesbania was controlled over 90% by all combinations, and no interactions occurred.
Field experiments were conducted at three locations in Mississippi in 1995 and 1996 to evaluate labeled and alternative herbicides and herbicide combinations for weed desiccation prior to soybean harvest. Weeds evaluated included pitted morningglory, hemp sesbania, spotted spurge, common cocklebur, and sicklepod. Soybean yield and harvestable soybean losses were not affected by preharvest herbicide treatments, spray volume, or surfactant concentration. Soybean moisture was most consistently reduced by glufosinate compared to the untreated and other herbicides and herbicide combinations evaluated. Most desiccation treatments at Stoneville and Brooksville resulted in foreign material similar to the weed-free check. Glufosinate at 0.84, 1.1, and 1.4 kg ai/ha desiccated all weeds evaluated 90% or more with no differences among rates. The addition of 3.4 or 6.7 kg ai/ha sodium chlorate to 0.28 kg ai/ha paraquat, 1.1 and 2.2 kg ai/ha glyphosate, or 0.28 and 0.56 kg ai/ha oxyfluorfen increased desiccation of most weeds evaluated, with no difference between sodium chlorate rates. In some instances, reducing application volume from 281 to 94 L/ha improved pitted morningglory desiccation when 0.28 g/ha paraquat was applied alone. There were no differences between 0.25 and 0.50% (v/v) surfactant for most parameters evaluated.
Reflectance data were subjected to a variety of analysis methods to determine the utility of hyperspectral reflectance for differentiating soybean, soil, and six weed species commonly found in Mississippi agricultural fields. Weed species evaluated were hemp sesbania, palmleaf morningglory, pitted morningglory, prickly sida, sicklepod, and smallflower morningglory. Hyperspectral reflectance data were collected from mature plant leaves three times in 2002 and two times in 2003. Vegetation indices were calculated and subjected to principal component analysis (PCA) and linear discriminant analysis (LDA). The PCA, using vegetation indices, produced the poorest classification accuracies for the plant species studied, generally less than 50%, whereas LDA resulted in classification accuracies greater than those from PCA. Best spectral band combination (BSBC) provided the greatest classification accuracies, with all better than 80% for all data sets. The BSBC indicated three wavelength bands of interest for species discrimination in the short wavelength infrared portion of the electromagnetic spectrum, which are not commonly used in current vegetation indices for species differentiation. These areas of interest were located from 1,445 to 1,475 nm, 2,030 to 2,090 nm, and 2,115 to 2,135 nm. The top 10 wavelengths determined by BSBC were then added to the vegetation indices and reanalyzed using PCA and LDA. Classification accuracies increased for all species when these wavelengths were added rather than using vegetation indices alone, suggesting greater crop and weed species differentiation can be obtained when using sensors that include these wavelength regions of the short wavelength infrared portion of the electromagnetic spectrum.