Herbicides that inhibit very-long-chain fatty acids (VLCFAs) have been widely used for preemergence control of annual monocot and small-seeded dicot weed species, such as waterhemp, since their discovery in the 1950s. VLCFA-inhibiting herbicides are often applied in combination with active ingredients that possess residual activity on small-seeded broadleaf weeds, which can make their contribution to preemergence waterhemp control difficult to quantify. Bare-ground field experiments were designed to investigate the efficacy of eight VLCFA-inhibiting herbicides applied at their minimum and maximum labeled rates for control of Illinois waterhemp populations. Four different locations were selected, two of which contained previously characterized VLCFA inhibitor–resistant waterhemp populations in Champaign County (CHR) and McLean County (MCR). Two locations with VLCFA inhibitor–sensitive waterhemp populations included the University of Illinois South Farm in Urbana, IL, and the Orr Research Center in Perry, IL. Soils at the CHR, MCR, and Urbana locations contained greater than 3% organic matter, but less than 3% organic matter at Perry. Non-encapsulated acetochlor and alachlor controlled CHR and MCR waterhemp populations 28 d after treatment (DAT), whereas other VLCFA-inhibiting herbicides resulted in 61% and 76% control of the CHR and MCR populations, respectively. In contrast, all VLCFA-inhibiting herbicides resulted in 81% and 88% control of the Perry and Urbana waterhemp populations, respectively, 28 DAT. Waterhemp control decreased by 42 DAT, especially for the VLCFA inhibitor–resistant CHR and MCR populations. Overall, VLCFA-inhibiting herbicides remain effective for controlling sensitive waterhemp, but most are not effective for controlling VLCFA inhibitor–resistant waterhemp populations. Proper herbicide stewardship and integrated weed management practices should be implemented to maintain VLCFA-inhibiting herbicide efficacy for waterhemp management in the future.

Waterhemp [Amaranthus tuberculatus (Moq.) Sauer] is one of the most troublesome agronomic weeds in the midwestern United States. The rapid evolution and selection of herbicide-resistance traits in A. tuberculatus is a major challenge in managing this species. An A. tuberculatus population, designated CHR, was identified in 2012 in Champaign County, IL, and previously characterized as resistant to herbicides from six site-of-action groups: 2,4-D (Group 4), acetolactate synthase inhibitors (Group 2), protoporphyrinogen oxidase inhibitors (Group 14), 4-hydroxyphenylpyruvate dioxygenase inhibitors (Group 27), photosystem II inhibitors (Group 5), and very-long-chain fatty-acid synthesis inhibitors (Group 15). Recently, ineffective control of CHR was observed in the field after dicamba application. Therefore, this research was initiated to confirm dicamba resistance, quantify the resistance level, and investigate its inheritance in CHR. Multiple field trials were conducted at the CHR location to confirm poor control with dicamba and compare dicamba treatments with other herbicides. Greenhouse trials were conducted to quantify the resistance level in CHR and confirm genetic inheritance of the resistance. In field trials, dicamba did not provide more than 65% control, while glyphosate and glufosinate provided at least 90% control. Multiple accessions were generated from controlled crosses and evaluated in greenhouse trials. Greenhouse dicamba dose–response experiments indicated a resistance level of 5- to 10-fold relative to a sensitive parental line. Dose–response experiments using F1 lines indicated that dicamba resistance was an incompletely dominant trait. Segregation analysis with F2 and backcross populations indicated that dicamba resistance had moderate heritability and was potentially a multigenic trait. Although dicamba resistance was predominantly inherited as a nuclear trait, minor maternal inheritance was not completely ruled out. To our knowledge, CHR is one of the first cases of dicamba resistance in A. tuberculatus. Further studies will focus on elucidating the genes involved in dicamba resistance.

The Patient Registry for Adolescents and Adults with Stable Fontan Circulation aims to describe a contemporary cohort of Fontan patients who could be eligible for a clinical trial investigating macitentan, an endothelin receptor antagonist. This international, non-interventional, multicentre, cross-sectional, observational registry enrolled patients with “stable” Fontan circulation ≥10 years following extra-cardiac conduit or lateral tunnel procedure. Main exclusion criteria were NYHA functional class IV, reoperation of Fontan circulation, or signs of disease worsening. Patient characteristics at enrolment are described; available data were collected during a single registration visit. Of the 266 screened patients, 254 were included in this analysis. At enrolment, median (interquartile range) age was 24 (20;30) years, 37%/63% of patients were from the USA/Europe, 54% were male, 54%/47% had undergone extra-cardiac conduit/lateral tunnel procedures, and 95% were in NYHA functional class I or II. History of arrhythmia was more common in older patients and patients with lateral tunnel; overall prevalence was 19%. Most laboratory values were within the normal range but mean creatinine clearance was abnormally low (87.7 ml/min). Angiotensin-converting enzyme inhibitors were used by 48% of patients and their use was associated with creatinine clearance <90 ml/min (p = 0.007), as was Fontan completion at an older age (p = 0.007). 53.4% of patients had clinical characteristics that could potentially meet an endothelin receptor antagonist trial’s eligibility criteria. The PREpArE-Fontan registry describes a cohort of patients who could potentially participate in an endothelin receptor antagonist trial and identified early subtle signs of Fontan failure, even in “stable” patients.

Ice mélange has been postulated to impact glacier and fjord dynamics through a variety of mechanical and thermodynamic couplings. However, observations of these interactions are very limited. Here, we report on glaciological and oceanographic data that were collected from 2016 to 2017 at LeConte Glacier and Bay, Alaska, and serendipitously captured the formation, flow and break-up of ephemeral ice mélange. Sea ice formed overnight in mid-February. Over the subsequent week, the sea ice and icebergs were compacted by the advancing glacier terminus, after which the ice mélange flowed quasi-statically. The presence of ice mélange coincided with the lowest glacier velocities and frontal ablation rates in our record. In early April, increasing glacier runoff and the formation of a sub-ice-mélange plume began to melt and pull apart the ice mélange. The plume, outgoing tides and large calving events contributed to its break-up, which took place over a week and occurred in pulses. Unlike observations from elsewhere, the loss of ice mélange integrity did not coincide with the onset of seasonal glacier retreat. Our observations provide a challenge to ice mélange models aimed at quantifying the mechanical and thermodynamic couplings between ice mélange, glaciers and fjords.

Genome wide association studies (GWAS) of Schizophrenia (SZ) patients have identified common variants in ten genes including SMARCA2 (Koga et al., HMG, 2009). We found that the SZ-GWAS genes are part of an interacting network centered on SMARCA2 (Loe-Mie et al., HMG, 2010). Furthermore, SMARCA2 was found disrupted in SZ (Walsh et al., Science, 2008). SMARCA2 encodes the ATPase (BRM) of the SWI/SNF chromatin remodeling complex that is at the interface of genome and environmental adaptation.

Taking advantage of an Algerian trio cohort of one hundred SZ patients (Benmessaoud et al., BMC Psychiatry, 2008), we replicated the association of SNP rs2296212 localized in exon 33, already shown associated in Koga study and resulting in D1546E amino acid change in the SMARCA2 protein. We studied SMARCA2 codons and found that exon 33 displays a signature of positive evolution in the primate lineage.

Our working hypothesis is that the coding regions displaying positive selection are target of novel rare variants. To address this question, we sequenced two exons displaying positive evolution and one exon without evidence of positive evolution.

We found (i) that rare variants are significantly in excess in SZ-patients compared to their parents (p = 0.038, Fisher test) and (ii) a higher proportion of rare variants in the primate-accelerated exons compared with the non-evolutionary exon in SZ-patients (p = 0.032, Fisher test).

SMARCA2 exon sequencing and whole exome sequencing from patients harboring SNP rs2296212 common variant are under progress. Altogether, these results are expected to give new insights into the genetic architecture of SZ.

The Continuous Performance Test (CPT) has become an essential constituent of the neuropsychological investigation of schizophrenia. Also, a vast number of brain imaging studies, mostly PET investigations, have employed the CPT as a cognitive challenge and established a relative hypofrontality in schizophrenics compared to controls. The aim of the present investigation was to clarify whether this predescribed hypofrontality could also be verified using functional magnetic resonance imaging (fMRI). 20 healthy volunteers and 14 schizophrenics on stable neuroleptic medication were included. Imaging was performed using the CPT-double-T-version and a clinical 1.5 T MRI-scanner with a single slice technique and a T2*-weighted gradient-echo-sequence. The schizophrenics exhibited a decreased activation in the right mesial prefrontal cortex, the right cingulate and the left thalamus compared to controls. These results obtained by fMRI are discussed in relation to published findings using PET.

The genetic architecture of schizophrenia (SZ) is based on common variants identified by Genome Wide Association Studies (GWIS) and on rare variants. We found that the SZ-GWIS genes are part of an interacting network centered on SMARCA2 (Loe-Mie et al., HMG, 2010). Both rare and common variants have been identified in SMARCA2 gene (Koga et al., HMG, 2009; Walsh et al., Science, 2008).

Taking advantage of an Algerian trio cohort of one hundred SZ patients (Benmessaoud et al., BMC Psychiatry, 2008), we replicated the association of SNP rs2296212 localized in exon 33, resulting in D1546E amino acid change. We found that exon 33 displays a signature of positive evolution in the primate lineage, with an excess of rare variants in SZ-patients compared to their parents (p = 0.038, Fisher test) and a higher proportion of rare variants in the primate-accelerated exons compared with the non-evolutionary exon in SZ-patients (p = 0.032, Fisher test).

As SMARCA2/BRM protein is part of a large SWI/SNF protein complex involved in epigenetics regulation of synaptic plasticity (Lepagnol-Bestel et al., in preparation), this raises the question of possible rare variants in SMARCA2 gene and in genes encoding SMARCA2/BRM interactors, in particular for those displaying a signature of primate-accelerated evolution. A total of 17 genes have been selected: MEECP2, SMARCA2, DNMT1, SMARCA4, SMARCE1, EHMT2, SMARCC1, HDAC2, SIN3A, RCOR2, CSF2RA, TCF4, PGBD1, RBM9, UTP11L, DDX5, EWRS1. the sequencing data obtained from Roche 454 device will be presented.

Altogether, these results are expected to give new insights into the genetic architecture of SZ.

Addition of multispecies impurity ions to the total-f gyrokinetic particle-in-cell code XGCa is reported, including a cross-verification of neoclassical physics against the NEO code. This new version of the neoclassical gyrokinetic code XGCa is used to benchmark and confirm the previous reduced-equation-based prediction that high-$Z$ impurity particles in the Pfirsch–Schlüter regime can exhibit a significant level of up–down poloidal asymmetry, through the large parallel friction force, and thus influence the radial plasma transport significantly. The study is performed in a plasma with weak toroidal rotation. In comparison, when the impurity particles are in the plateau regime, the up–down poloidal asymmetry becomes weak, with the parallel friction force becoming weaker than the parallel viscous force. It is also found that the linearization of the perturbed distribution function, based on the small poloidal asymmetry assumption, can become invalid. Using the numerical data from XGCa, each term in the parallel fluid force-balance equation have been analysed to find that both the main ions and the electrons respond to the poloidal potential variation adiabatically when the high-$Z$ tungsten possesses large poloidal variation.

Experiments were initiated to characterize a waterhemp population (CHR) discovered in a central Illinois corn field after it was not controlled by the 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor topramezone. Field experiments conducted during 2014–2015 indicated that acetolactate synthase (ALS)-, protoporphyrinogen oxidase (PPO)-, photosystem II (PSII)-, and HPPD-inhibiting herbicides and the synthetic auxin 2,4-D did not control the CHR population. Laboratory experiments confirmed target site–based resistance mechanisms to ALS- and PPO-inhibiting herbicides. Herbicide doses required to reduce dry biomass 50% (GR50) were determined in greenhouse dose–response experiments, and indicated 16-fold resistance to the HPPD inhibitor mesotrione, 9.5-fold resistance to the synthetic auxin 2,4-D, and 252-fold resistance to the PSII inhibitor atrazine. Complementary results from field, laboratory, and greenhouse investigations indicate that the CHR population has evolved resistance to herbicides from five sites of action (SOAs): ALS-, PPO-, PSII-, and HPPD-inhibiting herbicides and 2,4-D. Herbicide use history for the field in which CHR was discovered indicates no previous use of 2,4-D.

The crystal structure of H3O+-exchanged pharmacosiderite (pharmacosiderite is KFe4(AsO4)3(OH)4·nH2O, sensu stricto) has been determined by single-crystal X-ray diffraction and refined to R1 = 0.0418. H3O+-exchanged pharmacosiderite, (H3O+)Fe4(AsO4)3(OH)4·4.5H2O, is cubic, space group Pm, with a = 7.982(9) Å, V = 508.5(9) Å3 and Z = 1. The structure broadly conforms to that of the general pharmacosiderite structure type, with the hydronium ion generated by partial protonation of a site corresponding to a molecule of water of crystallization and its symmetry-related equivalents. In addition, the structure of a “pharmacosiderite” from Cornwall, United Kingdom, in which no alkali metals could be detected, has been re-evaluated and found to be consistent with that of the H3O+- exchanged structure. Its composition is (H3O+)Fe4(AsO4)3(OH)4·4H2O, with the partially occupied water found for the exchanged structure at (½, ½, ½) being absent in this case.

In 2006 and 2007, farmers from two counties in Illinois reported failure to control waterhemp with glyphosate. Subsequent onsite field experiments revealed that the populations might be resistant to multiple herbicides. Greenhouse experiments therefore were conducted to confirm glyphosate resistance, and to test for multiple resistance to other herbicides, including atrazine, acifluorfen, lactofen, and imazamox. In glyphosate dose-response experiments, both populations responded similarly to a previously characterized glyphosate-resistant population (MO1). Both Illinois populations also demonstrated high frequencies of resistance to the acetolactate synthase (ALS) inhibitor, imazamox. Additionally, one of the populations demonstrated high frequencies of resistance to both atrazine and the protoporphyrinogen oxidase (PPO) inhibitor, lactofen. Furthermore, using combinations of sequential and tank-mix herbicide applications, individual plants resistant to herbicides spanning all four site-of-action groups were identified from one population. Molecular experiments were performed to provide an initial characterization of the resistance mechanisms and to provide confirmation of the presence of multiple resistance traits within the two populations. Both populations contained the W574L ALS mutation and the ΔG210 PPO mutation, previously shown to confer resistance to ALS and PPO inhibitors, respectively. Atrazine resistance in both populations is suspected to be metabolism-based, because a triazine target-site mutation was not identified. A P106S EPSPS mutation, previously reported to confer glyphosate resistance, was identified in one population. This mutation was identified in both resistant and sensitive plants from the population; however, and so more research is needed to determine the glyphosate-resistance mechanism(s). This is the first known case of a weed population in the United States possessing multiple resistance to herbicides from four site-of-action groups.

If an herbicide application fails to control a targeted weed community sufficiently, farmers may try to eliminate surviving weeds with a follow-up application (hereafter “respray”). Despite the implications of resprays on the spread of herbicide-resistant weeds, respray frequencies and causal factors are poorly understood. A two-part survey of glyphosate-resistant soybean fields and custom application services was conducted in Illinois during 2005 and 2006 to determine the relative frequency of respray requests for postemergence glyphosate, and to identify weed community factors associated with glyphosate respray requests. A meta-analysis was then utilized to project the impacts of weed community factors driving respray requests on crop yield. Glyphosate resprays were requested for 14% of surveyed fields in both 2005 (n = 43) and 2006 (n = 90). In 2005, respray requests were highly associated with both population densities of weed communities visible from roadsides and incidences of skips (i.e., rectangular areas of escaped weeds indicating custom application failure). A skip increased the odds of respray request by more than ninefold, and population densities of weed communities visible from roadsides were, on average, 2.5 times greater in respray-requested fields compared with nonrequested fields. In 2006, respray requests were associated with population densities of weed communities identified by walking through fields. Contrary to 2005, requests in 2006 were concentrated in those fields with low weed population densities. Prior to resprays, weed communities capable of causing substantial soybean yield loss were present in both respray-requested and nonrequested fields in 2005 but in only nonrequested fields in 2006. Although this investigation indicated that custom applicators can take actions to reduce respray requests (i.e., avoiding skips), farmers and custom applicators should be prepared to implement additional weed control after postemergence glyphosate applications because damaging weed communities may remain.

A waterhemp population (MCR) previously characterized as resistant to 4-hydroxyphenylpyruvate dioxygenase and photosystem II inhibitors demonstrated both moderate and high levels of resistance to acetolactate synthase (ALS) inhibitors. Plants from the MCR population exhibiting high resistance to ALS inhibitors contained the commonly found Trp574Leu ALS amino acid substitution, whereas plants with only moderate resistance did not have this substitution. A subpopulation (JG11) was derived from the MCR population in which the moderate-resistance trait was isolated from the Trp574Leu mutation. Results from DNA sequencing and ALS enzyme assays demonstrated that resistance to ALS inhibitors in the JG11 population was not due to an altered site of action. This nontarget-site ALS-inhibitor resistance was characterized with whole-plant dose–response experiments using herbicides from each of the five commercialized families of ALS-inhibiting herbicides. Resistance ratios ranging from 3 to 90 were obtained from the seven herbicides evaluated. Nontarget-site resistance to ALS has been rarely documented in eudicot weeds, and adds to the growing list of resistance traits evolved in waterhemp.

Field and greenhouse experiments were conducted to characterize the response of a waterhemp population from McLean County, IL to foliar-applied 4-hydroxyphenylpyruvate dioxygenase (HPPD) –inhibiting herbicides and determine the population's sensitivity to herbicides from other site-of-action groups. In the field, 10 to 15–cm-tall waterhemp treated with mesotrione at 105 g ai ha−1, tembotrione at 92 g ai ha−1, or topromezone at 18 g ai ha−1 had significantly greater biomass (≥ 10%) 14 d after treatment (DAT) than waterhemp harvested the day of herbicide application, indicating growth had occurred following herbicide application. Waterhemp growth stage at the time of herbicide application influenced control. Mesotrione applied at 105 g ha−1 alone or combined with atrazine at 560 g ai ha−1 provided significantly greater waterhemp control (≥ 66%) when applied to small waterhemp plants (2 to 5 cm tall) compared with applications made to plants 5 to 10 or 10 to 15 cm tall. Glyphosate, glufosinate, fomesafen, lactofen, or acifluorfen provided greater waterhemp control (≥ 68%) 7 and 14 DAT than mesotrione, dicamba, or 2,4-D. Control of this population with atrazine, chlorimuron, and imazethapyr did not exceed 12%. Results of a greenhouse experiment with waterhemp plants grown from field-collected seed were similar to field data, and confirm the McLean County population was poorly controlled with HPPD, photosystem II, and acetolactate synthase inhibitors.

A waterhemp population (McLean County resistant, MCR) from McLean County, Illinois is resistant to both mesotrione and atrazine by elevated rates of herbicide metabolism. Research was conducted to investigate the inheritance of these resistance traits. Resistant and sensitive plants were crossed to obtain reciprocal F1 populations, which were then used to create pseudo-F2 and backcross (to sensitive parent; BCS) populations. The various populations were evaluated with whole-plant herbicide efficacy studies in a greenhouse. The responses of the F1 populations to both mesotrione and atrazine were intermediate when compared with parental populations. In the case of atrazine, BCS and F2 populations segregated 1 : 1 and 1 : 3, respectively, for susceptibility (S) : resistance (R), at a dose that controlled the sensitive parent but not the F1 or resistant parent. For mesotrione, variability was observed within the F1 populations, suggesting that mesotrione resistance is multigenic and the resistant parents used in the cross were not homozygous at the resistance loci. Furthermore, at low mesotrione doses, more F2 plants survived than expected on the basis of a single-gene trait, whereas at high doses, fewer F2 plants survived than expected. Dry weight data confirmed the conclusions obtained from survival data. Specifically, atrazine responses segregated into two discrete classes (R and S) in both the F2 and BCS populations, whereas mesotrione responses showed continuous distributions of phenotypes in F2 and BCS populations. We conclude that metabolism-based atrazine resistance in MCR is conferred by a single major gene, whereas inheritance of mesotrione resistance in this population is complex.

Palmer amaranth, a dioecious summer annual forb, originating in Sonoran desert washes, compromises crop yields in much of the southern United States and its range is expanding northward. Appropriate tactics for managing this weed proactively in the Upper Midwest will depend on characterizing its damage niche, the geographic range in which it can reduce crop yields. We implemented a common garden study in 2011 and 2012, planting eight accessions of Palmer amaranth from the southern and midwestern United States, into soybean crops in southern, central, and northern Illinois, at a population density of 8 plants m−2 with a biocontainment protocol. Once Palmer amaranth plants initiated flowering, they were removed and burned. Weed survival, flowering, and weed biomass were measured, in addition to soybean yield and weather data. Analyses indicated that Palmer amaranth's damage niche in Illinois soybean was independent of weed genotype or maternal environment. Despite competing only briefly, Palmer amaranth reduced soybean yields in all site–years, indicating its damage niche in Illinois, and much of the Midwest, is limited primarily by seed immigration rate. These results highlight the urgent need for weed managers to learn Palmer amaranth identification, prevent seed introduction, and maintain a policy of zero seed return.

With the frequency of glyphosate-resistant waterhemp increasing throughout the Midwest, the identification of resistant populations has become important for managing this species. However, high-throughput screening for glyphosate resistance in the greenhouse is tedious and inefficient. Research was conducted to document the occurrence of glyphosate-resistant waterhemp throughout the state of Illinois, and to determine whether a molecular assay for 5-enolypyruvyl-shikimate-3-phosphate synthase (EPSPS) gene amplification can be used as an alternative means to detect resistant populations. Populations throughout the state of Illinois were collected in 2010 and screened for glyphosate resistance using a whole-plant assay in a greenhouse, and survivors were examined for EPSPS gene amplification. Of 80 populations investigated, 22 were glyphosate resistant based on the greenhouse screen, and gene amplification was identified in 20 (91%) of the resistant populations. Although there are multiple mechanisms for glyphosate resistance in waterhemp, a molecular test for EPSPS gene amplification provides a rapid alternative for identification of glyphosate resistance in most populations.

Miscanthus × giganteus cv. Illinois is a high-yielding perennial grass crop being developed for cellulosic biomass production in the United States. It is a sterile cultivar and must be established using plantlets or rhizomes; this asexual propagation is relatively expensive, thereby limiting more widespread acceptance. Perennial, tetraploid, seeded types of M. × giganteus have been developed that could reduce establishment costs, while producing high biomass yields. Weed control during the year of establishment is essential because this grass crop does not compete well with weeds in the establishment year. Greenhouse and field experiments were conducted to identify PRE and POST herbicides that would not adversely affect seeded M. × giganteus emergence or growth. Imazethapyr and quinclorac applied PRE had no negative affect on M. × giganteus growth in the greenhouse with respect to seedling emergence, plant height, observed injury symptoms, or fresh weight. In the field, plant emergence was significantly higher with quinclorac plus atrazine than the nontreated control, and emergence with isoxaflutole plus atrazine was not significantly different from the control. Six herbicides applied POST in the greenhouse showed little or no negative effect on miscanthus growth. In the field, several PRE plus POST herbicide combinations did not negatively affect M. × giganteus growth; however, none of these provided adequate weed control under irrigated conditions. Further evaluation of PRE and POST herbicides is needed to identify robust weed control options that are safe on seeded M. × giganteus.