Benchmarking the Agronomic Performance of Biodegradable Mulches against Polyethylene Mulch Film: A Meta-Analysis

Growers are interested in biodegradable alternatives to petroleum-based polyethylene mulch film (PEM). However, many growers cite limited knowledge about biodegradable mulch films (BDMs) as a significant barrier to adoption. Agronomic field tests of BDMs are often limited temporally or spatially, and the variability of performance results relative to PEM may be contributing to this perceived knowledge gap. Our objective was to use data available in the scientific literature to provide the first quantitative performance benchmark of BDMs against PEM. We extracted data from 66 articles for meta-analysis. Response ratios were calculated for comparison of BDMs relative to black PEM, and differences among categorical groups were determined using 95% bootstrap confidence intervals. Overall, BDMs reduced soil temperature by 4.5% ± 0.8% (±one standard error) compared to PEM, and temperatures were coolest beneath paper-based BDM. Starch-polyester BDM was less effective than PEM for weed control, but paper-based BDM reduced weed density and biomass by 85.7% ± 9.2%. Paper-based BDMs were particularly useful for controlling Cyperus spp. weeds. Despite differences in soil temperature and weed suppression, crop yields were not different between BDMs and PEM. Future research should focus on reducing costs, adding functional value, and increasing the biodegradability of BDMs.

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Cover Crop Effectiveness Varies in Cover Crop-Based Rotational Tillage Organic Soybean Systems Depending on Species and Environment

Agronomy ◽

10.3390/agronomy9060319 ◽

2019 ◽

Vol 9 (6) ◽

pp. 319 ◽

Cited By ~ 2

Author(s):

Laura Vincent-Caboud ◽

Léa Vereecke ◽

Erin Silva ◽

Joséphine Peigné

Keyword(s):

Cover Crops ◽

Weed Management ◽

Cover Crop ◽

Crop Yields ◽

Weed Suppression ◽

Future Research ◽

Weed Biomass ◽

Cereal Rye ◽

Cereal Grain ◽

Crop Biomass

Organic farming relies heavily on tillage for weed management, however, intensive soil disturbance can have detrimental impacts on soil quality. Cover crop-based rotational tillage (CCBRT), a practice that reduces the need for tillage and cultivation through the creation of cover crop mulches, has emerged as an alternative weed management practice in organic cropping systems. In this study, CCBRT systems using cereal rye and triticale grain species are evaluated with organic soybean directly seeded into a rolled cover crop. Cover crop biomass, weed biomass, and soybean yields were evaluated to assess the effects of cereal rye and winter triticale cover crops on weed suppression and yields. From 2016 to 2018, trials were conducted at six locations in Wisconsin, USA, and Southern France. While cover crop biomass did not differ among the cereal grain species tested, the use of cereal rye as the cover crop resulted in higher soybean yields (2.7 t ha−1 vs. 2.2 t ha−1) and greater weed suppression, both at soybean emergence (231 vs. 577 kg ha−1 of weed biomass) and just prior to soybean harvest (1178 vs. 1545 kg ha−1). On four out of six sites, cover crop biomass was lower than the reported optimal (<8000 kg ha−1) needed to suppress weeds throughout soybean season. Environmental conditions, in tandem with agronomic decisions (e.g., seeding dates, cultivar, planters, etc.), influenced the ability of the cover crop to suppress weeds regardless of the species used. In a changing climate, future research should focus on establishing flexible decision support tools based on multi-tactic cover crop management to ensure more consistent results with respect to cover crop growth, weed suppression, and crop yields.

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Weed Suppression by Live and Desiccated Hairy Vetch (Vicia villosa)

Weed Science ◽

10.1017/s0043174500076074 ◽

1993 ◽

Vol 41 (2) ◽

pp. 207-212 ◽

Cited By ~ 98

Author(s):

John R. Teasdale ◽

Craig S. T. Daughtry

Keyword(s):

Soil Temperature ◽

Bare Soil ◽

Weed Suppression ◽

Light Extinction ◽

Daily Maximum ◽

Hairy Vetch ◽

Vicia Villosa ◽

Winter Annual ◽

Density And Biomass ◽

Temperature Amplitude

Hairy vetch was grown as a winter annual cover crop and evaluated for weed suppression when desiccated by paraquat or left alive until natural senescence in a 3-yr field experiment. Total weed density and biomass were variable in the desiccated hairy vetch treatment relative to a bare soil treatment but were consistently lower in the live hairy vetch treatment relative to the desiccated or bare soil treatments. An average of 87% of sites under live hairy vetch compared to 8% of sites under desiccated hairy vetch transmitted less than 1% of unobstructed sunlight. The red (660 nm) to far-red (730 nm) ratio of transmitted light was reduced by 70% under live hairy vetch compared to 17% under desiccated hairy vetch. Daily maximum soil temperature and diurnal soil temperature amplitude were reduced by live hairy vetch > desiccated hairy vetch > bare soil. Soil moisture content was greater under both live and desiccated hairy vetch compared to bare soil during droughty periods. Changes in light extinction, red to far-red ratio, and diurnal soil temperature amplitude were sufficient to explain greater weed suppression by live than desiccated hairy vetch.

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Weed suppression with hydramulch, a biodegradable liquid paper mulch in development

Renewable Agriculture and Food Systems ◽

10.1079/raf2006154 ◽

2006 ◽

Vol 21 (4) ◽

pp. 216-223 ◽

Cited By ~ 11

Author(s):

J.P. Warnick ◽

C.A. Chase ◽

E.N. Rosskopf ◽

E.H. Simonne ◽

J.M. Scholberg ◽

...

Keyword(s):

Soil Moisture ◽

Soil Temperature ◽

Weed Management ◽

Management Practices ◽

Organic Production ◽

Weed Suppression ◽

Vegetable Production ◽

North Central ◽

Purple Nutsedge ◽

Polyethylene Mulch

AbstractCost-effective, laborsaving, and environmentally sound weed management practices are needed for sustainable vegetable production. Organic production, in particular, precludes the use of synthetic herbicides and requires that organic farmers utilize practices that reduce harmful environmental impact. Although polyethylene film mulch is used extensively in vegetable production in Florida, its use has a number of drawbacks, among which is the susceptibility of opaque polyethylene mulch to penetration by yellow and purple nutsedge. Appreciable labor and disposal/environmental costs are associated with its removal. A durable mulch material that would effectively control nutsedge and other weeds but with no associated environmental and disposal costs is highly desirable. Hydramulch, a paper-like material applied as a slurry consisting of cotton waste, newsprint, gypsum and a proprietary adhesive, was tested as a biodegradable alternative to polyethylene mulch during the spring of 2003. Experiments were conducted in southeastern and north-central Florida to compare the effects of three hydramulch formulations, polyethylene mulch and a no mulch control on soil temperature, soil moisture and weed infestation. Soil temperature under hydramulch was 1–4°C lower than that under polyethylene. In the absence of rain, the use of hydramulch resulted in soil moisture levels that were 1–4% lower than with polyethylene mulch. Higher soil moisture with hydramulch than polyethylene was coincident with rainfall. Hydramulch remained intact on most beds and suppressed broadleaf weeds and grasses, particularly at the north-central site where the mulch was applied at a greater thickness. However, purple nutsedge readily penetrated hydramulch. Therefore, hydramulch may be applicable for use for the suppression of broadleaf weeds and grasses at sites with little or no nutsedge pressure in fall or in crops for which cooler soils are desirable or crops that are rainfed or overhead irrigated.

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No Tillage and Strip Tillage Effects on Plant Performance, Weed Suppression, and Profitability in Transitional Organic Broccoli Production

HortScience ◽

10.21273/hortsci10706-16 ◽

2016 ◽

Vol 51 (9) ◽

pp. 1103-1110 ◽

Cited By ~ 5

Author(s):

Dana Jokela ◽

Ajay Nair

Keyword(s):

Soil Temperature ◽

Cover Crop ◽

Soil Health ◽

Weed Suppression ◽

Production Costs ◽

Plant Performance ◽

Research Station ◽

No Tillage ◽

Strip Tillage ◽

Density And Biomass

Organic no-till and strip-till systems have gained attention because of their reported capacity to enhance soil health and suppress annual weeds. This study, conducted at the Horticulture Research Station, Ames, IA, over 2 years (2013–14 and 2014–15) compared a cover crop–based no tillage (NT), strip tillage (ST), and conventional tillage (CT) in transitional organic broccoli (Brassica oleracea L. var. italica) production, with data collected on broccoli yield and quality, plant health, weed suppression, soil temperature, and cost of production. A cover crop mixture of cereal rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth.) was seeded in all plots in September, and was ended by rolling and crimping (NT and ST) or soil incorporation (CT) in late spring the following year. Each whole-plot tillage treatment was split into two subplot fertility treatments—one based entirely on organic preplant granular fertilizer, and the other split between preplant granular fertilizer and postplanting fertigation—to test the effect of fertigation on yield and plant growth under the typically nitrogen (N)-limited reduced tillage conditions. In 2014, yield of broccoli was highest in CT treatments, averaging 5.4 t·ha−1, with no difference between ST and NT treatments. In 2015, yields were equal among tillage treatments, averaging 20.0 t·ha−1. Changing the timing of fertilizer application through the use of fertigation did not affect yield. Weed density and biomass were lowest in the between-row (BR) regions of NT and ST plots in 2014, indicating effective early-season weed suppression. In 2015, NT and ST plots generally had lower weed biomass and density compared with CT plots, but weed growth in BR and in-row (IR) regions of NT and ST plots was similar. Soil temperature was highest in CT plots throughout the year, and higher in ST than in NT plots only during some periods. While production costs did vary slightly across treatments, profit per hectare was most strongly affected by yield. Our findings suggest that cover crop–based organic NT and ST systems may be viable options for organic broccoli growers.

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Chasing the Anchor: A Systematic Review and Meta-analysis of Perceptual Anchoring Deficits in Developmental Dyslexia

10.31234/osf.io/amzpj ◽

2020 ◽

Author(s):

Kurt D Shulver ◽

Nicholas A Badcock

Keyword(s):

Systematic Review ◽

Reading Ability ◽

English Language ◽

Prediction Interval ◽

Meta Analysis ◽

Visual Assessment ◽

Individual Performance ◽

Future Research ◽

Significant Heterogeneity ◽

Eligibility Criteria

We report the results of a systematic review and meta-analysis investigating the relationship between perceptual anchoring and dyslexia. Our goal was to assess the direction and degree of effect between perceptual anchoring and reading ability in typical and atypical (dyslexic) readers. We performed a literature search of experiments explicitly assessing perceptual anchoring and reading ability using PsycInfo (Ovid, 1860 to 2020), MEDLINE (Ovid, 1860 to 2019), EMBASE (Ovid, 1883 to 2019), and PubMed for all available years up to June (2020). Our eligibility criteria consisted of English-language articles and, at minimum, one experimental group identified as dyslexic - either by reading assessment at the time, or by previous diagnosis. We assessed for risk of bias using an adapted version of the Newcastle-Ottawa scale. Six studies were included in this review, but only five (n = 280 participants) were included in the meta-analysis (we were unable to access the necessary data for one study).The overall effect was negative, large and statistically significant; g = -0.87, 95% CI [-1.47, 0.27]: a negative effect size indicating less perceptual anchoring in dyslexic versus non-dyslexic groups. Visual assessment of funnel plot and Egger’s test suggest minimal bias but with significant heterogeneity; Q (4) = 9.70, PI (prediction interval) [-2.32, -0.58]. The primary limitation of the current review is the small number of included studies. We discuss methodological limitations, such as limited power, and how future research may redress these concerns. The variability of effect sizes appears consistent with the inherent variability within subtypes of dyslexia. This level of dispersion seems indicative of the how we define cut-off thresholds between typical reading and dyslexia populations, but also the methodological tools we use to investigate individual performance.

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Autobiographical Memory Impairments as a Transdiagnostic Feature of Mental Illness: A meta-analysis of autobiographical memory specificity and overgenerality amongst people with psychiatric diagnoses

10.31234/osf.io/ab5cu ◽

2020 ◽

Author(s):

Tom Joseph Barry ◽

David John Hallford ◽

Keisuke Takano

Keyword(s):

Autobiographical Memory ◽

Memory Retrieval ◽

Keyword Search ◽

Meta Analysis ◽

Future Research ◽

Psychiatric Diagnoses ◽

Schizophrenia Spectrum Disorders ◽

Memory Impairments ◽

Memory Specificity ◽

Causal Mechanisms

Decades of research has examined the difficulty that people with psychiatric diagnoses, such as Major Depressive Disorder, Schizophrenia Spectrum Disorders, and Posttraumatic Stress Disorder, have in recalling specific autobiographical memories from events that lasted less than a day. Instead, they seem to retrieve general events that have occurred many times or which occurred over longer periods of time, termed overgeneral memory. We present the first transdiagnostic meta-analysis of memory specificity/overgenerality, and the first meta-regression of proposed causal mechanisms. A keyword search of Embase, PsycARTICLES and PsycINFO databases yielded 74 studies that compared people with and without psychiatric diagnoses on the retrieval of specific (k = 85) or general memories (k = 56). Multi-level meta-analysis confirmed that people with psychiatric diagnoses typically recall fewer specific (g = -0.864, 95% CI[-1.030, -0.698]) and more general (g = .712, 95% CI[0.524, 0.900]) memories than diagnoses-free people. The size of these effects did not differ between diagnostic groups. There were no consistent moderators; effect sizes were not explained by methodological factors such as cue valence, or demographic variables such as participants’ age. There was also no support for the contribution of underlying processes that are thought to be involved in specific/general memory retrieval (e.g., rumination). Our findings confirm that deficits in autobiographical memory retrieval are a transdiagnostic factor associated with a broad range of psychiatric problems, but future research should explore novel causal mechanisms such as encoding deficits and the social processes involved in memory sharing and rehearsal.

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Challenges and Opportunities for Neuroimaging in Young Patients with Traumatic Brain Injury: a Coordinated Effort towards Advancing Discovery from the ENIGMA Pediatric Moderate/Severe TBI Group

10.31234/osf.io/y2txh ◽

2019 ◽

Cited By ~ 4

Author(s):

Emily L. Dennis ◽

Karen Caeyenberghs ◽

Robert F. Asarnow ◽

Talin Babikian ◽

Brenda Bartnik-Olson ◽

...

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Meta Analysis ◽

Young Patients ◽

Future Research ◽

Childhood And Adolescence ◽

Developmental Issues ◽

Challenges And Opportunities ◽

Severe Tbi ◽

Advance Research

Traumatic brain injury (TBI) is a major cause of death and disability in children in both developed and developing nations. Children and adolescents suffer from TBI at a higher rate than the general population; however, research in this population lags behind research in adults. This may be due, in part, to the smaller number of investigators engaged in research with this population and may also be related to changes in safety laws and clinical practice that have altered length of hospital stays, treatment, and access to this population. Specific developmental issues also warrant attention in studies of children, and the ever-changing context of childhood and adolescence may require larger sample sizes than are commonly available to adequately address remaining questions related to TBI. The ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) Pediatric Moderate-Severe TBI (msTBI) group aims to advance research in this area through global collaborative meta-analysis. In this paper we discuss important challenges in pediatric TBI research and opportunities that we believe the ENIGMA Pediatric msTBI group can provide to address them. We conclude with recommendations for future research in this field of study.

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Comparing Instructional Approaches in Caregiver-Implemented Intervention: An Interdisciplinary Systematic Review and Meta-Analysis

Journal of Early Intervention ◽

10.1177/1053815121989807 ◽

2021 ◽

pp. 105381512198980

Author(s):

Bailey J. Sone ◽

Jordan Lee ◽

Megan Y. Roberts

Keyword(s):

Adult Learning ◽

Family Involvement ◽

Meta Analysis ◽

Future Research ◽

Instructional Approaches ◽

Comparative Efficacy ◽

Robust Variance ◽

Analysis Methodology ◽

Intervention Models ◽

Variance Estimate

Family involvement is a cornerstone of early intervention (EI). Therefore, positive caregiver outcomes are vital, particularly in caregiver-implemented interventions. As such, caregiver instructional approaches should optimize adult learning. This study investigated the comparative efficacy of coaching and traditional caregiver instruction on caregiver outcomes across EI disciplines. A systematic search for articles was conducted using PRISMA guidelines. Meta-analysis methodology was used to analyze caregiver outcomes, and a robust variance estimate model was used to control for within-study effect size correlations. Seven relevant studies were ultimately included in the analysis. A significant, large effect of coaching on caregiver outcomes was observed compared to other models of instruction ( g = 0.745, SE = 0.125, p = .0013). These results support the adoption of a coaching framework to optimize caregiver outcomes in EI. Future research should examine how coaching and traditional instruction can be used in tiered intervention models with a variety of populations.

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Cybersickness in current-generation virtual reality head-mounted displays: systematic review and outlook

Virtual Reality ◽

10.1007/s10055-021-00513-6 ◽

2021 ◽

Author(s):

Polona Caserman ◽

Augusto Garcia-Agundez ◽

Alvar Gámez Zerban ◽

Stefan Göbel

Keyword(s):

Systematic Review ◽

Virtual Reality ◽

Meta Analysis ◽

Subjective Evaluation ◽

Future Research ◽

Current Generation ◽

Research Areas ◽

Head Mounted Displays ◽

Skin Response ◽

Golden Standard

AbstractCybersickness (CS) is a term used to refer to symptoms, such as nausea, headache, and dizziness that users experience during or after virtual reality immersion. Initially discovered in flight simulators, commercial virtual reality (VR) head-mounted displays (HMD) of the current generation also seem to cause CS, albeit in a different manner and severity. The goal of this work is to summarize recent literature on CS with modern HMDs, to determine the specificities and profile of immersive VR-caused CS, and to provide an outlook for future research areas. A systematic review was performed on the databases IEEE Xplore, PubMed, ACM, and Scopus from 2013 to 2019 and 49 publications were selected. A summarized text states how different VR HMDs impact CS, how the nature of movement in VR HMDs contributes to CS, and how we can use biosensors to detect CS. The results of the meta-analysis show that although current-generation VR HMDs cause significantly less CS ($$p<0.001$$ p < 0.001 ), some symptoms remain as intense. Further results show that the nature of movement and, in particular, sensory mismatch as well as perceived motion have been the leading cause of CS. We suggest an outlook on future research, including the use of galvanic skin response to evaluate CS in combination with the golden standard (Simulator Sickness Questionnaire, SSQ) as well as an update on the subjective evaluation scores of the SSQ.

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Research on the Operating Characteristics of Hydraulic Free-Piston Engines: A Systematic Review and Meta-Analysis

Energies ◽

10.3390/en14123530 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3530

Author(s):

Fukang Ma ◽

Shuanlu Zhang ◽

Zhenfeng Zhao ◽

Yifang Wang

Keyword(s):

Systematic Review ◽

High Efficiency ◽

Meta Analysis ◽

Combustion Process ◽

Research Progress ◽

Future Research ◽

Operating Characteristics ◽

Piston Engine ◽

Free Piston ◽

Free Piston Engine

The hydraulic free-piston engine (HFPE) is a kind of hybrid-powered machine which combines the reciprocating piston-type internal combustion engine and the plunger pump as a whole. In recent years, the HFPE has been investigated by a number of research groups worldwide due to its potential advantages of high efficiency, energy savings, reduced emissions and multi-fuel operation. Therefore, our study aimed to assess the operating characteristics, core questions and research progress of HFPEs via a systematic review and meta-analysis. We included operational control, starting characteristics, misfire characteristics, in-cylinder working processes and operating stability. We conducted the literature search using electronic databases. The research on HFPEs has mainly concentrated on four kinds of free-piston engine, according to piston arrangement form: single piston, dual pistons, opposed pistons and four-cylinder complex configuration. HFPE research in China is mainly conducted in Zhejiang University, Tianjin University, Jilin University and the Beijing Institute of Technology. In addition, in China, research has mainly focused on the in-cylinder combustion process while a piston is free by considering in-cylinder combustion machinery and piston dynamics. Regarding future research, it is very important that we solve the instabilities brought about by chance fluctuations in the combustion process, which will involve the hydraulic system’s efficiency, the cyclical variation, the method of predicting instability and the recovery after instability.

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