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Potential effectiveness of harvest weed seed control (HWSC) systems depends upon seed shatter of the target weed species at crop maturity, enabling its collection and processing at crop harvest. However, seed retention likely is influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed shatter phenology in thirteen economically important broadleaf weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to four weeks after physiological maturity at multiple sites spread across fourteen states in the southern, northern, and mid-Atlantic U.S. Greater proportions of seeds were retained by weeds in southern latitudes and shatter rate increased at northern latitudes. Amaranthus species seed shatter was low (0 to 2%), whereas shatter varied widely in common ragweed (Ambrosia artemisiifolia L.) (2 to 90%) over the weeks following soybean physiological maturity. Overall, the broadleaf species studied shattered less than ten percent of their seeds by soybean harvest. Our results suggest that some of the broadleaf species with greater seed retention rates in the weeks following soybean physiological maturity may be good candidates for HWSC.
Seed shatter is an important weediness trait on which the efficacy of harvest weed seed control (HWSC) depends. The level of seed shatter in a species is likely influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed shatter of eight economically important grass weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to four weeks after maturity at multiple sites spread across eleven states in the southern, northern, and mid-Atlantic U.S. From soybean maturity to four weeks after maturity, cumulative percent seed shatter was lowest in the southern U.S. regions and increased as the states moved further north. At soybean maturity, the percent of seed shatter ranged from 1 to 70%. That range had shifted to 5 to 100% (mean: 42%) by 25 days after soybean maturity. There were considerable differences in seed shatter onset and rate of progression between sites and years in some species that could impact their susceptibility to HWSC. Our results suggest that many summer annual grass species are likely not ideal candidates for HWSC, although HWSC could substantially reduce their seed output at during certain years.
Information on performance of sequential treatments of quizalofop-P-ethyl with florpyrauxifen-benzyl is lacking. Field studies were conducted in 2017 and 2018 at Stoneville, MS, to evaluate sequential timings of quizalofop-P-ethyl with florpyrauxifen-benzyl included in preflood treatments. Quizalofop-P-ethyl treatments were no quizalofop-P-ethyl and sequential applications of quizalofop-P-ethyl at 120 followed by (fb) 120 g ai ha-1 applied to rice in the two- to three-leaf (EPOST) fb the four-leaf to one-tiller (LPOST) growth stages or LPOST fb 10 d after flooding (PTFLD); quizalofop-P-ethyl at 100 fb 139 g ha-1 EPOST fb LPOST or LPOST fb PTFLD; quizalofop-P-ethyl at 139 fb 100 g ha-1 EPOST fb LPOST and LPOST fb PTFLD; and quizalofop-P-ethyl at 85 fb 77 g ha-1 fb 77 g ha-1 EPOST fb LPOST fb PTFLD. Quizalofop-P-ethyl was applied alone and in mixture with florpyrauxifen-benzyl at 29 g ai ha-1 LPOST. Visible rice injury 14 d after PTFLD (DA-PTFLD) was ≤3%. Visible control of volunteer rice (‘CL151’ and ‘Rex’) 7 DA-PTFLD was similar and ≥ 95% for each quizalofop-P-ethyl treatment. Barnyardgrass control with quizalofop-P-ethyl at 120 fb 120 g ha-1 LPOST fb PTFLD was greater (88%) in mixture with florpyrauxifen-benzyl. The addition of florpyrauxifen-benzyl to quizalofop-P-ethyl increased rough rice yield when quizalofop-P-ethyl was applied at 100 fb 139 g ha-1 EPOST fb LPOST. Sequential applications of quizalofop-P-ethyl at 120 fb 120 g ha-1 EPOST fb LPOST, 100 fb 139 g ha-1 EPOST fb LPOST, or 139 fb 100 g ha-1 EPOST fb LPOST controlled grass weed species. The addition of florpyrauxifen-benzyl was not beneficial for grass weed control; however, since quizalofop-P-ethyl does not control broadleaf weeds, florpyrauxifen-benzyl could provide broad-spectrum weed control in ACCase-resistant rice.
Background: Peritoneal dialysis is a type of dialysis performed by patients in their homes; patients receive training from dialysis clinic staff. Peritonitis is a serious complication of peritoneal dialysis, most commonly caused by gram-positive organisms. During March‒April 2019, a dialysis provider organization transitioned ~400 patients to a different manufacturer of peritoneal dialysis equipment and supplies (from product A to B). Shortly thereafter, patients experienced an increase in peritonitis episodes, caused predominantly by gram-negative organisms. In May 2019, we initiated an investigation to determine the source. Methods: We conducted case finding, reviewed medical records, observed peritoneal dialysis procedures and trainings, and performed patient home visits and interviews. A 1:1 matched case–control study was performed in 1 state. A case had ≥2 of the following: (1) positive peritoneal fluid culture, (2) high peritoneal fluid white cell count with ≥50% polymorphonuclear cells, or (3) cloudy peritoneal fluid and/or abdominal pain. Controls were matched to cases by week of clinic visit. Conditional logistic regression was used to estimate univariate matched odds ratios (mOR) and 95% confidence intervals (CIs). We conducted microbiological testing of peritoneal dialysis fluid bags to rule out product contamination. Results: During March‒September 2019, we identified 157 cases of peritonitis across 15 clinics in 2 states (attack rate≍39%). Staphylococcus spp (14%), Serratia spp (12%) and Klebsiella spp (6.3%) were the most common pathogens. Steps to perform peritoneal dialysis using product B differed from product A in several key areas; however, no common errors in practice were identified to explain the outbreak. Patient training on transitioning products was not standardized. Outcomes of the 73 cases in the case–control study included hospitalization (77%), peritoneal dialysis failure (40%), and death (7%). The median duration of training prior to product transition was 1 day for cases and controls (P = .86). Transitioning to product B (mOR, 18.00; 95% CI, 2.40‒134.83), using product B (mOR, 18.26; 95% CI, 3.86‒∞), drain-line reuse (mOR, 4.67; 95% CI, 1.34‒16.24) and performing daytime exchanges (mOR, 3.63; 95% CI, 1.71‒8.45) were associated with peritonitis. After several interventions, including transition of patients back to product A (Fig. 1), overall cases declined. Sterility testing of samples from 23 unopened product B peritoneal dialysis solution bags showed no contamination. Conclusions: Multiple factors may have contributed to this large outbreak, including a rapid transition in peritoneal dialysis products and potentially inadequate patient training. Efforts are needed to identify and incorporate best training practices, and product advances are desired to improve the safety of patient transitions between different types of peritoneal dialysis equipment.
Global climate change is the largest existential threat of our time. Glaciers are retreating, sea levels are rising, extreme weather is intensifying and the last four years have been the hottest on record (NASA, 2020; World Meteorological Organization, 2020). Although climate change is already significantly impacting natural and human systems around the world, mitigating further and potentially disastrous climate change will require large-scale individual and collective action, including public support for mitigation policies, as well as the more rapid development and implementation of adaptation plans (van der Linden et al., 2015; Pearson et al., 2016).
Florpyrauxifen-benzyl and quizalofop were available for POST applications in 2018; however, little is known about the response of acetyl-CoA carboxylase (ACCase)–resistant rice cultivars and advanced lines to POST herbicides. A field study was conducted in 2017 and 2018 at Stoneville, MS, to characterize the response of ACCase-resistant rice cultivars and advanced lines to POST applications of florpyrauxifen-benzyl. The imidazolinone-resistant (IR) rice cultivars ‘CL163’ and ‘CLXL 745’, and ACCase-resistant rice cultivars ‘PVL01’, ‘PVL013’, ‘PVL024-B’, ‘PVL038’, ‘PVL080’, and ‘PVL081’were treated with florpyrauxifen-benzyl at 0 (nontreated control for each cultivar) and 58 g ai ha–1 at the four-leaf to one-tiller (LPOST) growth stage. At 14 d after treatment (DAT), PVL01 was injured 5% to 6% greater than CLXL 745, PVL013, and PVL081; however, injury was ≤10% at that evaluation for all cultivars. Similarly, injury was ≤13% for all cultivars 28 DAT. Mature heights were reduced for all cultivars except PVL013 and PVL081. Rough rice yield was ≥100% of the control for all cultivars except PVL081, PVL013, and CL163. Results suggest that florpyrauxifen-benzyl can safely be applied POST to rice cultivars grown in Mississippi as well as ACCase-resistant cultivars that are currently under development.
Schools have been recognised as a potential setting for improving young peoples’ food and beverage choices; however, many schools fail to adhere to healthy food and beverage policy standards. The current study aimed to explore the enablers and barriers to effective implementation of and compliance with school-based food and beverage policies.
Systematic review and meta-synthesis. Eight electronic databases were searched for articles in June 2019. Studies were eligible for inclusion if they reported on implementation and/or compliance of school-based food and/or beverage policies with outcomes relating to enablers and/or barriers. This review had no restrictions on study design, year of publication or language. Seventy-two full-text articles were assessed for eligibility, of which twenty-eight were included in this review.
Studies conducted globally that focused on schools.
School-based healthy food and beverage policies.
Financial (cost of policy-compliant foods, decreased profit and revenue), physical (availability of policy-compliant foods, close geographical proximity to unhealthy food outlets) and social (poor knowledge, understanding, and negative stakeholders’ attitudes towards policy) factors were the most frequently reported barriers for policy implementation. Sufficient funding, effective policy communication and management, and positive stakeholders’ attitudes were the most frequently reported enablers for policy implementation.
There is a need for better communication strategies, financial and social support prior to school-based food policy implementation. Findings of this review contribute to a thorough understanding of factors that underpin best practice recommendations for the implementation of school-based food policy, and inform those responsible for improving public health nutrition.
The rate of manifestation of depressive episodes can vary appreciably. The complete development of a depressive episode may be very rapid, taking less than one hour or be very slow, taking up to one month. Altough this clinical observation suggests different neurobiological pathomechanisms, the onset speed of depressive episodes in different affective disorders has not been investigated systematically up to now. The objective of this study was to establish the onset speed of depressive episodes in patients with a history of at least one depressive episode and to compare the onset speed in unipolar with that in bipolar affective disorders.
A group of 96 inpatients was investigated consecutively using the structured patient interview “Onset of Depression Inventory” (ODI). In 76 patients, there was a unipolar depressive disorder and 20 patients suffered from a bipolar depressive disorder.
The onset speed of the current depressive episode in patients with effective disorders correlated significantly with the onset speed of the previous depressive episodes (p < 0.001). Furthermore, there was a significant difference in the onset of the depressive episodes between unipolar and bipolar affective disorders (p < 0.001). In 55% of patients with a bipolar disorder, the depressive episode was manifested within one week whereas this was the case in only 22,37% of the patients with a unipolar affective disorder.
The rate of manifestation of depressive episodes differs between unipolar and bipolar disorders. The clinical observation reported here can support the diagnostic appraisal of depressive episodes.
The aim of the study was to investigate the influence of agomelatine and venlafaxine on driving skills and on driving performance in an on-road driving test in depressed inpatients.
40 depressed inpatients were randomly assigned to treatment with either agomelatine (n=20) or venlafaxine (n=20). Patients were tested before pharmacologic treatment (t0), and on days 14 (t1) and 28 (t2) with computerized tests and additionally were rated in an on-road driving test on day 28 by a licensed driving instructor. To control for retest effects a group of 20 healthy subjects was examined in the same time schedule.
After two weeks of treatment with agomelatine or venlafaxine patients showed a significant reduction in depressive symptoms, and a distinct improvement in concentration and stress-tolerance. Furthermore, prior discharge to outpatient treatment (day 28), 72.5% of patients were labeled abundantly fit to drive in the on-road driving test, in 22.5% of cases a satisfactory performance was certified and in 5% of our patient sample there were slight concerns with respect to fitness to drive. Patients did not however reach performance level in functional domains of healthy controls. Significant differences between treatment groups could not be observed.
Our results indicate that depressed patients treated with agomelatine or venlafaxine show a better test performance on tasks related to driving skills than do untreated patients Besides, most patients could be rated as fit to drive, on an actual driving test conducted by a licensed driving instructor, prior discharge to outpatient treatment.
− The role of the state as an agent of earth system governance has become more complex, contingent, and interdependent. − Although participatory and collaborative processes have contributed to more effective, equitable, and legitimate environmental governance outcomes in some instances, analyses of these processes should be situated within a broader governance perspective, which recasts questions of policy change around questions of power and justice. −The complexity and normative aspects of agency in earth system governance requires new forms of policy evaluation that account for social impacts and the ability of governance systems to adapt. − Many of the core analytical concepts in ESG–Agency scholarship, such as agency, power, authority, and accountability, remain under-theorized. In addition, some types of actors, including women, labor, non-human agents, those who work against earth system governance, and many voices from the Global South, remain largely hidden. − ESG–Agency scholars need to develop research projects and collaborations in understudied regions while also recruiting and supporting scholars in those regions to engage with this research agenda.
Rice with enhanced tolerance to herbicides that inhibit acetyl coA carboxylase (ACCase) allows POST application of quizalofop, an ACCase-inhibiting herbicide. Two concurrent field studies were conducted in 2017 and 2018 near Stoneville, MS, to evaluate control of grass (Grass Study) and broadleaf (Broadleaf Study) weeds with sequential applications of quizalofop alone and in mixtures with auxinic herbicides applied in the first or second application. Sequential treatments of quizalofop were applied at 119 g ai ha−1 alone and in mixtures with labeled rates of auxinic herbicides to rice at the two- to three-leaf (EPOST) or four-leaf to one-tiller (LPOST) growth stages. In the Grass Study, no differences in rice injury or control of volunteer rice (‘CL151’ and ‘Rex’) were detected 14 and 28 d after last application (DA-LPOST). Barnyardgrass control at 14 and 28 DA-LPOST with quizalofop applied alone or with auxinic herbicides EPOST was ≥93% for all auxinic herbicide treatments except penoxsulam plus triclopyr. Barnyardgrass control was ≥96% with quizalofop applied alone and with auxinic herbicides LPOST. In the Broadleaf Study, quizalofop plus florpyrauxifen-benzyl controlled more Palmer amaranth 14 DA-LPOST than other mixtures with auxinic herbicides, and control with this treatment was greater EPOST compared with LPOST. Hemp sesbania control 14 DA-LPOST was ≤90% with quizalofop plus quinclorac LPOST, orthosulfamuron plus quinclorac LPOST, and triclopyr EPOST or LPOST. All mixtures except quinclorac and orthosulfamuron plus quinclorac LPOST controlled ivyleaf morningglory ≥91% 14 DA-LPOST. Florpyrauxifen-benzyl or triclopyr were required for volunteer soybean control >63% 14 DA-LPOST. To optimize barnyardgrass control and rice yield, penoxsulam plus triclopyr and orthosulfamuron plus quinclorac should not be mixed with quizalofop. Quizalofop mixtures with auxinic herbicides are safe and effective for controlling barnyardgrass, volunteer rice, and broadleaf weeds in ACCase-resistant rice, and the choice of herbicide mixture could be adjusted based on weed spectrum in the treated field.
The dynamics and wall collision of inertial particles were investigated in non-isotropic turbulence of a horizontal liquid channel flow. The inertial particles were
glass beads at a volumetric concentration of 0.03 %. The bead-laden flow and the unladen base case had the same volumetric flow rates, with a shear Reynolds number,
, of the unladen flow equal to 410 based on the half-channel height and friction velocity. Lagrangian measurements of three-dimensional trajectories of both fluid tracers and glass beads were obtained using time-resolved particle tracking velocimetry based on the shake-the-box algorithm of Schanz et al. (Exp. Fluids, vol. 57, no. 5, 2016, pp. 1–27). The analysis showed that on average the near-wall glass beads decelerate in the streamwise direction, while farther away from the wall, the streamwise acceleration of the glass beads became positive. The ejection motions provided a local maximum streamwise acceleration above the buffer layer by transporting glass beads to high velocity layers and exposing them to a high drag force in the streamwise direction. Conversely, the sweep motion made the maximum contribution to the average streamwise deceleration of glass beads in the near-wall region. The wall-normal acceleration of the beads was positive in the vicinity of the wall, and it became negative farther from the wall. The investigation showed that the glass beads with sweeping motion had the maximum momentum, streamwise deceleration, and wall-normal acceleration among all the beads close to the wall and these values increased with increasing their trajectory angle. The investigation of the beads that collided with the wall showed that those with shallow impact angles (less than
) typically slide along the wall. The sliding beads had a small streamwise momentum exchange of
during these events. The duration of their sliding motion could be as much as five times the inner time scale of the unladen flow. The wall-normal velocity of these beads after sliding was greater than their wall-normal velocity before sliding, and was associated with the rotation induced lift force. Beads with impact angles greater than
had shorter interaction times with the wall and smaller streamwise and wall-normal restitution ratios.
Carbapenemase-producing Enterobacteriaceae (CPE) pose a significant global health threat.
To conduct a systematic review of health outcomes and long-term sequelae attributable to CPE infection.
We followed PRISMA reporting guidelines and published our review protocol on PROSPERO (CRD42018097357). We searched Medline, Embase, CINAHL and the Cochrane Library. We included primary studies with a carbapenem-susceptible control group in high-income countries, published in English. Quality appraisal was completed using Joanna Briggs Institute checklists. We qualitatively summarized frequently reported outcomes and conducted a meta-analysis.
Our systematic review identified 8,671 studies; 17 met the eligibility criteria for inclusion. All studies reported health outcomes; none reported health-related quality-of-life. Most studies were from Europe (65%), were conducted in teaching or university-affiliated hospitals (76%), and used case-control designs (53%). Mortality was the most commonly reported consequence of CPE-infections; in-hospital mortality was most often reported (62%). Our meta-analysis (n = 5 studies) estimated an absolute risk difference (ARD) for in-hospital bloodstream infection mortality of 0.25 (95% confidence interval [CI], 0.17–0.32). Duration of antibiotic therapy (range, 4–29.7 vs 1–23.6 days) and length of hospital stay (range, 21–87 vs 15–43 days) were relatively higher for CPE-infected patients than for patients infected with carbapenem-susceptible pathogens. Most studies (82%) met >80% of their respective quality appraisal criteria.
The risk of in-hospital mortality due to CPE bloodstream infection is considerably greater than carbapenem-susceptible bloodstream infection (ARD, 0.25; 95% CI, 0.17–0.32). Health outcome studies associated with CPE infection are focused on short-term (eg, in-hospital) outcomes; long-term sequelae and quality-of-life are not well studied.
Evidence-based parenting support (EBPS) programs derived from social learning theory, cognitive behavioural principles, and developmental theory are among the most successful innovations in the entire field of psychological intervention. EBPS programs have been at the cutting edge of global dissemination efforts to increase community access to evidence-based parenting programs. Despite the widely recognised success of these efforts, existing models of parenting intervention are not a panacea, and much can be done to improved outcomes. Efforts to improve outcomes have included the emergence of a population-based approach to increase reach of intervention. This has included the development of flexible delivery modalities, including online parenting interventions, the incorporation of strategies to enhance cultural relevance and acceptability of programs, and more recently, applications with parents in very low resource settings. Further enhancements of outcomes are likely to be forthcoming as we gain a better understanding of the mechanisms that explain positive intervention effects and non-response to interventions. More cost-effective online professional training models are needed to disseminate and promote the sustained use of EBPS programs. New interventions are required for the most vulnerable parents when parenting concerns are complicated by other problems such as trauma, addictions, relationship conflict, family violence, mental health problems and intergenerational poverty. However, to scale effective programs, Commonwealth and state government policies and funding priorities need to respond to evidence about what works and make sustained investments in the implementation of parenting programs. Possible strategies to enhance the policy impact of intervention research are discussed.
The amplification of reward-seeking behavior under uncertainty described by Anselme & Güntürkün is based on the animal literature. However, this phenomenon could provide valuable information for the understanding of several dysfunctional human behaviors such as overeating and gambling. Therefore, we formulated some considerations on how the “incentive hope” hypothesis could be tested on a human population.
Following pioneering work in Norway, cirque glaciers have widely been viewed as rigidly rotating bodies. This model is incorrect for basin-filling cirque glaciers, as we have demonstrated at West Washmawapta Glacier, a small glacier in the Canadian Rocky Mountains. Here we report observations at the same glacier that assess whether complex temporal variations of flow also occur. For parts of three summers, we measured daily displacements of the glacier surface. In one year, four short-duration speed-up events were recorded. Three of the events occurred during the intervals of warmest weather, when melt was most rapid; the fourth event occurred immediately following heavy rain. We interpret the speed-up events as manifestations of enhanced water inputs to the glacier bed and associated slip lubrication by increased water volumes and pressures. No further speed-ups occurred in the final month of the melt season, despite warm temperatures and several rainstorms; the dominant subglacial water system likely transformed from one of poorly connected cavities to one with an efficient channel network. The seasonal evolution of hydrology and flow resembles behaviors documented at other, larger temperate glaciers and indicates that analyses of cirque erosion cannot rely on simple assumptions about ice dynamics.
Supergiant X-ray Binaries host a compact object, generally a neutron star, orbiting an evolved O/B star. Mass transfer proceeds through the intense radiatively-driven wind of the stellar donor, a fraction of which is captured by the gravitational field of the neutron star. The subsequent accretion process onto the neutron star is responsible for the abundant X-ray emission from those systems. They also display variations in time of the X-ray flux by a factor of a few 10, along with changes in the hardness ratios believed to be due to varying absorption along the line-of-sight. We used the most recent results on the inhomogeneities (aka clumps) in the non-stationary wind of massive hot stars to evaluate their impact on the time-variable accretion process. We ran three-dimensional simulations of the wind in the vicinity of the accretor to witness the formation of the bow shock and follow the inhomogeneous flow over several spatial orders of magnitude, down to the neutron star magnetosphere. In particular, we show that the impact of the clumps on the time-variability of the intrinsic mass accretion rate is severely damped by the crossing of the shock, compared to the purely ballistic Bondi-Hoyle-Lyttleton estimation. We also account for the variable absorption due to clumps passing by the line-of-sight and estimate the final effective variability of the mass accretion rate for different orbital separations. These results are confronted to recent analysis of Vela X-1 observations with Chandra by Grinberg et al. (2017). It shows that clumps account well for time-variability at low luminosity but can not generate, per se, the high luminosity activity observed.
Understanding the complex behavior of High Mass X-ray binaries (HMXBs) is not possible without detailed information about their donor stars. While crucial, this turns out to be a challenge on multiple fronts. First, multi-wavelength spectroscopy is vital. As such systems can be highly absorbed, this is often already hard to accomplish. Secondly, even if the spectroscopic data is available, the determination of reliable stellar parameters requires sophisticated model atmospheres that accurately describe the outermost layers and the wind of the donor star.
For early-type donors, the stellar wind is radiatively driven and there is a smooth transition between the outermost layers of the star and the wind. The intricate non-LTE conditions in the winds of hot stars complicate the situation even further, as proper model atmospheres need to account for a multitude of physics to accurately provide stellar and wind parameters. The latter are especially crucial for the so-called “wind-fed” HXMBs, where the captured wind of the supergiant donor is the only source for the material accreted by the compact object.
In this review I will briefly address the different approaches for treating stellar winds in the analysis of HMXBs. The fundamentals of stellar atmosphere modeling will be discussed, also addressing the limitations of modern models. Examples from recent analysis results for particular HMXBs will be outlined. Furthermore, the path for the next generation of stellar atmosphere models will be outlined, where models can be used not only for measurement purposes, but also to make predictions and provide a laboratory for theoretical conclusions. Stellar atmospheres are a key tool in understanding HMXBs, e.g. by providing insights about the accretion of stellar winds onto the compact object, or by placing the studied systems in the correct evolutionary context in order to identify potential gravitational wave (GW) progenitors.
Classical Wolf-Rayet stars are evolved, hydrogen depleted massive stars that exhibit strong mass-loss. In theory, these stars can form either by intrinsic mass loss (stellar winds or eruptions), or via mass-removal in binaries. The Wolf-Rayet stars in the Magellanic Clouds are often thought to have originated through binary interaction due to the low ambient metallicity and, correspondingly, reduced wind mass-loss. We performed a complete spectral analysis of all known WR binaries of the nitrogen sequence in the Small and Large Magellanic Clouds, as well as additional orbital analyses, and constrained the evolutionary histories of these stars. We find that the bulk of Wolf-Rayet stars are luminous enough to be explained by single-star evolution. In contrast to prediction, we do not find clear evidence for a large population of low-luminosity Wolf-Rayet stars that could only form via binary interaction, suggesting a discrepancy between predictions and observations.
The antiquity of iron meteorites and the inferred early intense heating by the decay of 26Al suggest that many planetesimals were molten beneath a thin insulating cap at the same time as chondrules were being made. As those planetesimals were colliding and merging, it seems inevitable that impact plumes of droplets from their liquid interiors would have been launched into space and cooled to form chondrules. We call the process splashing; it is quite distinct from making droplets by jetting during hypervelocity impacts. Evidence both for the existence of molten planetesimals, and for the cooling of chondrules within a plume setting, is strong and growing. Detailed petrographic and isotopic features of chondrules, particularly in carbonaceous chondrites (that probably formed beyond the orbit of Jupiter), suggest that the chondrule plume would have been ‘dirty’ and the otherwise uniform droplets would have been contaminated with earlier-formed dust and larger grains from a variety of sources. The contamination possibly accounts for relict grains, for the spread of oxygen isotopes along the primitive chondrule mineral (PCM) line in carbonaceous chondrites, and for the newly recognized nucleosynthetic isotopic complementarity between chondrules and matrix in Allende.