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1.
Plants (Basel) ; 13(10)2024 May 09.
Article in English | MEDLINE | ID: mdl-38794373

ABSTRACT

Severe cadmium contamination poses a serious threat to food security and human health. Plant-microbial combined remediation represents a potential technique for reducing heavy metals in soil. The main objective of this study is to explore the remediation mechanism of cadmium-contaminated soil using a combined approach of lawn plants and microbes. The target bacterium Bacillus cereus was selected from cadmium-contaminated soil in mining areas, and two lawn plants (Festuca arundinacea A'rid III' and Poa pratensis M'idnight II') were chosen as the target plants. We investigated the remediation effect of different concentrations of bacterial solution on cadmium-contaminated soil using two lawn plants through pot experiments, as well as the impact on the soil microbial community structure. The results demonstrate that Bacillus cereus promotes plant growth, and the combined action of lawn plants and Bacillus cereus improves soil quality, enhancing the bioavailability of cadmium in the soil. At a bacterial suspension concentration of 105 CFU/mL, the optimal remediation treatment was observed. The removal efficiency of cadmium in the soil under Festuca arundinacea and Poa pratensis treatments reached 33.69% and 33.33%, respectively. Additionally, the content of bioavailable cadmium in the rhizosphere soil increased by up to 13.43% and 26.54%, respectively. Bacillus cereus increased the bacterial diversity in the non-rhizosphere soil of both lawn plants but reduced it in the rhizosphere soil. Additionally, the relative abundance of Actinobacteriota and Firmicutes, which have potential for heavy metal remediation, increased after the application of the bacterial solution. This study demonstrates that Bacillus cereus can enhance the potential of lawn plants to remediate cadmium-contaminated soil and reshape the microbial communities in both rhizosphere and non-rhizosphere soils.

2.
Article in English | MEDLINE | ID: mdl-38557405

ABSTRACT

Background: Environmental exposures impact amyotrophic lateral sclerosis (ALS) risk and progression, a fatal and progressive neurodegenerative disease. Better characterization of these exposures is needed to decrease disease burden. Objective: To identify exposures in the residential setting that associate with ALS risk, survival, and onset segment. Methods: ALS and control participants recruited from University of Michigan completed a survey that ascertained exposure risks in the residential setting. ALS risk was assessed using logistic regression models followed by latent profile analysis to consider exposure profiles. A case-only analysis considered the contribution of the residential exposure variables via a Cox proportional hazards model for survival outcomes and multinomial logistic regression for onset segment, a polytomous outcome. Results: This study included 367 ALS and 255 control participants. Twelve residential variables were associated with ALS risk after correcting for multiple comparison testing, with storage in an attached garage of chemical products including gasoline or kerosene (odds ratio (OR) = 1.14, padjusted < 0.001), gasoline-powered equipment (OR = 1.16, padjusted < 0.001), and lawn care products (OR = 1.15, padjusted < 0.001) representing the top three risk factors sorted by padjusted. Latent profile analysis indicated that storage of these chemical products in both attached and detached garages increased ALS risk. Although residential variables were not associated with poorer ALS survival following multiple testing corrections, storing pesticides, lawn care products, and woodworking supplies in the home were associated with shorter ALS survival using nominal p values. No exposures were associated with ALS onset segment. Conclusion: Residential exposures may be important modifiable components of the ALS susceptibility and prognosis exposome.

3.
Am J Emerg Med ; 80: 18-23, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38479112

ABSTRACT

AIMS: To characterize the clinical features of ocular trauma resulting from lawn mower, identify determinants of unfavorable final visual acuity (FVA), and assess the spectrum of microbial in posttraumatic endophthalmitis. METHODS: This retrospective study enrolled patients who experienced ocular trauma due to lawn mower at Zhongshan Ophthalmic Center from January 2013 to August 2021. Demographics, clinical features, isolated microorganisms, risk factors influencing reduced visual acuity, treatment regimens, and utilization of eyewear were collected. RESULTS: The study included 140 participants (140 eyes) (49.47 ± 12.03 years, 95% male). The predominant injury manifestations were penetrating globe injuries (75.7%) and intraocular foreign bodies (51.4%). Endophthalmitis occurred in 35 cases (25%) and Bacillus cereus (23.5%) was the primary pathogen, followed by Staphylococcus epidermidis (11.8%) and Streptococcus species (11.8%). Following the initial assessment, where 77.9% of patients had initial visual acuity (IVA) at grade IV (ranging from light perception to 4/200) and only 0.7% attained grade I (better than 20/40), post-treatment results revealed that 5.7% achieved FVA at grade I, with a concurrent decrease in patients with grade IV vision to 64.3%. Multivariate logistic regression revealed that injury protection (p < 0.001, OR = 0.237, 95% CI = 0.126-0.446), IVA (p = 0.001, OR = 4.102, 95% CI = 1.730-9.729), and retinal detachment (p = 0.042, OR = 8.105, 95% CI = 1.075-61.111) were significant independent risk factors impacting FVA. CONCLUSION: Lawn mower often cause severe ocular injuries, with high-velocity metal foreign bodies that can lead to infections, most commonly caused by Bacillus cereus. Correct use of protective gear, initial vision assessment, and detecting retinal detachment are crucial for visual prognosis.


Subject(s)
Endophthalmitis , Visual Acuity , Humans , Male , Female , Middle Aged , Retrospective Studies , Endophthalmitis/microbiology , Endophthalmitis/epidemiology , Adult , Eye Foreign Bodies/complications , Eye Foreign Bodies/epidemiology , Eye Injuries, Penetrating/complications , Eye Injuries, Penetrating/epidemiology , Eye Injuries/epidemiology , Eye Injuries/complications , Risk Factors , Aged , China/epidemiology
4.
Orthop Traumatol Surg Res ; 110(1S): 103771, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38000507

ABSTRACT

Open fracture is rare in children, raising dual issues of sepsis and mechanics. Here, we address certain practical questions regarding childhood open fracture. Should the recognized adult classifications be used in children? Two classifications exist for adults, without pediatric specificities; of these, we recommend Gustilo's, as being more precise in its description of severe grades. Is there any consensus on emergency prophylactic antibiotic therapy in children? The risks seem to be the same, and 24hours' prophylactic antibiotic therapy should be initiated as soon as possible, as in adults. What are the most recent guidelines on time to treatment, type of internal fixation and possible associated procedures in tibial fracture in children? Wound cleansing is indispensable. Treatment under anesthesia can be delayed up to 24hours in the absence of neurovascular complications on condition that antibiotic therapy is implemented immediately. In Gustilo grade I and II, or IIIA, external fixation is not systematic and non-operative treatment or intramedullary nailing is possible. In grades IIIB and IIIC, external fixation is the rule, although conversion is possible if indicated early enough. Do the particular cases of nail bed injury or lawn mower foot injury in children require specific management? Nail bed injury is not to be minimized and should be treated strictly. In case of serious accidents with garden equipment, initial wound care in surgery should be economic, but experienced practitioners should weigh the risk/benefit ratio between conservation and early amputation. LEVEL OF EVIDENCE: IV.


Subject(s)
Fracture Fixation, Intramedullary , Fractures, Open , Tibial Fractures , Adult , Humans , Child , Adolescent , Fractures, Open/surgery , Fracture Fixation, Internal/methods , Tibial Fractures/surgery , Anti-Bacterial Agents/therapeutic use , Treatment Outcome , Fracture Healing , Retrospective Studies
5.
Front Psychol ; 14: 1259920, 2023.
Article in English | MEDLINE | ID: mdl-38022966

ABSTRACT

Within urban green spaces, spontaneous groundcovers, as potential alternatives for traditional lawns, have garnered attention due to their ecological adaptability. However, little attention has been paid to whether spontaneous groundcovers can serve as suitable replacements for lawns in terms of the aesthetic values and human preferences for each. Based on questionnaires accompanied by photo elicitation, this study explored the perceptions of and preferences for seven kinds of lawns and six kinds of spontaneous groundcovers in China. The effects of social backgrounds on people's perceptions of and preferences for ground covers were also analyzed. The results indicated a general equivalence in preferences for the lawn and spontaneous groundcover. The Taraxacum mongolicum - Cynodon dactylon - Conyza canadensis community was significantly preferred most among all of the selected ground covers. Spontaneous groundcovers were regarded as more natural, wild, variable, and species-richer compared to lawns, while lawns were perceived as better kept than spontaneous groundcovers. Ground covers were preferred which were perceived to have high ecological aesthetic value and low wildness. Industry and attention to herbaceous plants mostly affected human perceptions and preferences among the social background factors, and gender, age, education level, and occupation also had significant effects. The results thus provide the support for the application of spontaneous groundcovers in moderately developed cities, but such application should consider the comprehensive development of ecological aesthetic value and the applicability of different groups of residents.

6.
Inj Epidemiol ; 10(Suppl 1): 51, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37864276

ABSTRACT

BACKGROUND: Riding lawn mower injuries are the most common cause of major limb loss in young U.S. children. Our study objective was to investigate the circumstances surrounding pediatric riding lawn mower injuries and to identify potential contributing risk factors and behaviors leading to these events. METHODS: Followers/members of both a public and a private lawn mower injury support and prevention Facebook page who had or were aware of children who had suffered a lawn mower-related injury were invited to complete an electronic survey on Qualtrics. Duplicate cases and those involving push mowers were removed. Frequencies and chi-square analyses were performed. RESULTS: 140 injured children were identified with 71% of surveys completed by parents and 19% by an adult survivor of a childhood incident. The majority of injured children were Caucasian (94%), male (64%), and ≤ 5 years of age at the time of the incident (63%). Bystanders were 69% of those injured, 24% were lawn mower riders, and mower operators and others accounted for 7%. The lawn mower operator was usually male (77%), being the father/stepfather in almost half. Overall, 59% of injuries occurred while traveling in reverse, 29% while moving forward. Nearly all (92%) had an amputation and/or permanent disability. Subgroup analysis (n = 130) found injured bystanders were younger than injured passengers with 71% versus 45% being < 5 years of age, respectively (p = 0.01). Over three-quarters of bystander incidents occurred while moving in reverse as compared to 17% of passenger incidents (p < 0.01). Amputations and/or permanent disabilities were greater among bystanders (97%) as compared to passengers (79%, p = 0.01). Only 3% of bystanders had an upper extremity injury as compared to 21% of passengers (p = 0.01). Seventy-three percent of bystander victims had received at least one ride on a lawn mower prior to their injury incident. CONCLUSIONS: Child bystanders seriously injured by riding lawn mowers were frequently given prior rides likely desensitizing them to their inherent dangers and leading them to seek rides when mowers were being used. Engineering changes preventing blade rotation when traveling in reverse and not giving children rides (both when and when not mowing) may be critical in preventing mower-related injuries.

7.
J Environ Manage ; 346: 118919, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37729836

ABSTRACT

Globally, greenhouse gas (GHG) reduction is a serious concern. To evaluate whether turfs serve as a GHG sink or source, GHG budget assessments for life cycle are required. However, previous studies have only focused on the use of turfs. To bridge these gaps in literature, this study investigated GHG (CO2, N2O, and CH4) emissions from the disposal of grass clippings and soil GHG fluxes in turfs. Additionally, GHG budgets in the turf production phase were assessed. Finally, inclusive GHG budgets from turf production to disposal of grass clippings for four turf uses (soccer stadium, golf course, office, and urban park) were assessed. Grass clippings were disposed in three forms (incineration, leaving as-is, and biochar). We found that GHG emissions from incineration and leaving 1 t-fresh weight (FW) of grass clippings were 0.711 and 0.207 t-CO2e, respectively. Contrastingly, the GHG emissions from the biochar yield from 1 t-FW of grass clippings were -0.200 t-CO2e. Further, annual soil GHG fluxes in newly established Zoysia and Kentucky bluegrass turfs were calculated at 0.067 and 0.040 tCO2eï½¥ha-1ï½¥yr-1, respectively. As the turf grass in production fields sequester large amounts of CO2, GHG budgets in turf production phase were estimated at approximately -20 t-CO2eï½¥ha-1ï½¥yr-1. Inclusive GHG budget assessment from turf production to disposal of grass clippings showed that turfs only in the urban parks served as a GHG sink and this ability was comparable to CO2 sequestration in forests. To enhance the ability of GHG sinks and to promote changes from a GHG source to GHG sink, our study revealed the importance of reduction of GHG emissions from energy and resource uses (especially fertilizers and gasoline) for turf management.

8.
Oecologia ; 202(2): 337-351, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37286887

ABSTRACT

Land-use change is highly dynamic globally and there is great uncertainty about the effects of land-use legacies on contemporary environmental performance. We used a chronosequence of urban grasslands (lawns) that were converted from agricultural and forested lands from 10 to over 130 years prior to determine if land-use legacy influences components of soil biodiversity and composition over time. We used historical aerial imagery to identify sites in Baltimore County, MD (USA) with agricultural versus forest land-use history. Soil samples were taken from these sites as well as from existing well-studied agricultural and forest sites used as historical references by the National Science Foundation Long-Term Ecological Research Baltimore Ecosystem Study program. We found that the microbiomes in lawns of agricultural origin were similar to those in agricultural reference sites, which suggests that the ecological parameters on lawns and reference agricultural systems are similar in how they influence soil microbial community dynamics. In contrast, lawns that were previously forest showed distinct shifts in soil bacterial composition upon recent conversion but reverted back in composition similar to forest soils as the lawns aged over decades. Soil fungal communities shifted after forested land was converted to lawns, but unlike bacterial communities, did not revert in composition over time. Our results show that components of bacterial biodiversity and composition are resistant to change in previously forested lawns despite urbanization processes. Therefore land-use legacy, depending on the prior use, is an important factor to consider when examining urban ecological homogenization.


Subject(s)
Ecosystem , Microbiota , Soil , Forests , Biodiversity , Urbanization , Soil Microbiology , Agriculture
9.
Adv Sci (Weinh) ; 10(19): e2205479, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37129311

ABSTRACT

Nitride perovskite LaWN3 has been predicted to be a promising ferroelectric material with unique properties for diverse applications. However, due to the challenging sample preparation at ambient pressure, the crystal structure of this nitride remains unsolved, which results in many ambiguities in its properties. Here, the authors report a comprehensive study of LaWN3 based on high-quality samples synthesized by a high-pressure method, leading to a definitive resolution of its crystal structure involving nitrogen deficiency. Combined with theoretical calculations, these results show that LaWN3 adopts an orthorhombic Pna21 structure with a polar symmetry, possessing a unique atomic polarization along the c-axis. The associated atomic polar distortions in LaWN3 are driven by covalent hybridization of W: 5d and N: 2p orbitals, opening a direct bandgap that explains its semiconducting behaviors. The structural stability and electronic properties of this nitride are also revealed to be closely associated with its nitrogen deficiency. The success in unraveling the structural and electronic ambiguities of LaWN3 would provide important insights into the structures and properties of the family of nitride perovskites.

10.
Microorganisms ; 11(2)2023 Feb 04.
Article in English | MEDLINE | ID: mdl-36838363

ABSTRACT

Myxobacteria prey upon a broad range of microorganisms. Lawn assays are commonly used to quantify myxobacterial predation-myxobacterial suspensions are spotted onto prey lawns, and monitored via spot expansion. The diversity in motility behaviours of myxobacterial strains and differing assay protocols in myxobacteriology laboratories led us to develop a highly-specified assay, which was applied to 28 myxobacterial strains preying on seven phytopathogenic prey species. Generally, prey organisms showed no qualitative differences in their susceptibility/resistance to myxobacterial predation. For most myxobacteria, prey did not stimulate, and in ~50% of cases actively hindered colony expansion. Only ~25% of predator/prey strain combinations exhibited greater colony expansion than in the absence of nutrients. The activity of predatory strains against different prey correlated, implying effective predators may have relatively non-specific predation mechanisms (e.g., broad specificity proteases/lipases), but no correlation was observed between predatory activity and phylogeny. Predation on dead (but intact) or lysed prey cells gave greater colony expansion than on live prey. Occasional strains grew substantially faster on dead compared to lysed cells, or vice-versa. Such differences in accessing nutrients from live, dead and lysed cells indicates there are strain-specific differences in the efficiencies/machineries of prey killing and nutrient acquisition, which has important implications for the ecology of myxobacterial predators and their prey.

11.
Glob Chang Biol ; 29(12): 3489-3502, 2023 06.
Article in English | MEDLINE | ID: mdl-36825371

ABSTRACT

Urban land-use change has the potential to affect local to global biogeochemical carbon (C) and nitrogen (N) cycles and associated greenhouse gas (GHG) fluxes. We conducted a meta-analysis to (1) assess the effects of urbanization-induced land-use conversion on soil nitrous oxide (N2 O) and methane (CH4 ) fluxes, (2) quantify direct N2 O emission factors (EFd ) of fertilized urban soils used, for example, as lawns or forests, and (3) identify the key drivers leading to flux changes associated with urbanization. On average, urbanization increases soil N2 O emissions by 153%, to 3.0 kg N ha-1  year-1 , while rates of soil CH4 uptake are reduced by 50%, to 2.0 kg C ha-1  year-1 . The global mean annual N2 O EFd of fertilized lawns and urban forests is 1.4%, suggesting that urban soils can be regional hotspots of N2 O emissions. On a global basis, conversion of land to urban greenspaces has increased soil N2 O emission by 0.46 Tg N2 O-N year-1 and decreased soil CH4 uptake by 0.58 Tg CH4 -C year-1 . Urbanization driven changes in soil N2 O emission and CH4 uptake are associated with changes in soil properties (bulk density, pH, total N content, and C/N ratio), increased temperature, and management practices, especially fertilizer use. Overall, our meta-analysis shows that urbanization increases soil N2 O emissions and reduces the role of soils as a sink for atmospheric CH4 . These effects can be mitigated by avoiding soil compaction, reducing fertilization of lawns, and by restoring native ecosystems in urban landscapes.


Subject(s)
Ecosystem , Soil , Soil/chemistry , Climate Change , Urbanization , Forests , Nitrous Oxide/analysis , Methane/analysis , Carbon Dioxide/analysis
12.
Animals (Basel) ; 14(1)2023 Dec 19.
Article in English | MEDLINE | ID: mdl-38200733

ABSTRACT

The populations of European hedgehog (Erinaceus europaeus) are in decline, and it is essential that research identifies and mitigates the factors causing this. Hedgehogs are increasingly sharing habitats with humans, being exposed to a range of dangers in our backyards. Previous research has documented that some models of robotic lawn mowers can cause harm to hedgehogs. This study explored the personality and behaviour of 50 live hedgehogs when facing an approaching, disarmed robotic lawn mower. By combining a novel arena and novel object test, we found that 27 hedgehogs could be categorised as "shy" and 23 as "bold", independently of sex and age. The encounter tests with a robotic lawn mower showed that the hedgehogs positioned themselves in seven different ways. Personality did not affect their reactions. Adult hedgehogs tended to react in a shyer manner, and the hedgehogs, generally, acted less boldly during their second encounter with the robotic lawn mower. Additionally, our results show that bold individuals reacted in a more unpredictable way, being more behaviourally unstable compared to the shy individuals. This knowledge will be applied in the design of a standardised hedgehog safety test, eventually serving to produce and approve hedgehog-friendly robotic lawn mowers.

13.
Animals (Basel) ; 14(1)2023 Dec 29.
Article in English | MEDLINE | ID: mdl-38200853

ABSTRACT

Previous research has established that some models of robotic lawn mowers are potentially harmful to hedgehogs. As the market for robotic lawn mowers is expanding rapidly and the populations of European hedgehogs (Erinaceus europaeus) are in decline, it is important to investigate this risk further to understand the potential threat which some robotic lawn mowers may pose to hedgehogs. We tested 19 models of robotic lawn mowers in collision with hedgehog cadavers to measure their effect on hedgehogs. Our results showed that some models of robotic lawn mowers may injure hedgehogs, whereas others are not harmful to them. Apart from one single incidence, all robotic lawn mowers had to physically touch the hedgehog carcasses to detect them. Larger hedgehog cadavers were less likely to be "injured", with height being the most influential measure of size. The firmness of the tested hedgehog cadavers (frozen or thawed) did not influence the outcome of the collision tests. Neither the position of the hedgehog cadavers nor the selected technical features of the lawn mowers affected the probability of injury. Based on the results, we designed a standardised safety test to measure the effect of a specific model of robotic lawn mower on hedgehogs.

14.
Plants (Basel) ; 11(19)2022 Sep 22.
Article in English | MEDLINE | ID: mdl-36235344

ABSTRACT

Plants are key components of the terrestrial ecosystem carbon cycle. Atmospheric CO2 is assimilated through photosynthesis and stored in plant biomass and in the soil. The use of turfgrass is expanding due to the increasing human population and urbanization. In this review, we summarize recent carbon sequestration research in turfgrass and compare turfgrass systems to other plant systems. The soil organic carbon (SOC) stored in turfgrass systems is comparable to that in other natural and agricultural systems. Turfgrass systems are generally carbon-neutral or carbon sinks, with the exception of intensively managed areas, such as golf course greens and athletic fields. Turfgrass used in other areas, such as golf course fairways and roughs, parks, and home lawns, has the potential to contribute to carbon sequestration if proper management practices are implemented. High management inputs can increase the biomass productivity of turfgrass but do not guarantee higher SOC compared to low management inputs. Additionally, choosing the appropriate turfgrass species that are well adapted to the local climate and tolerant to stresses can maximize CO2 assimilation and biomass productivity, although other factors, such as soil respiration, can considerably affect SOC. Future research is needed to document the complete carbon footprint, as well as to identify best management practices and appropriate turfgrass species to enhance carbon sequestration in turfgrass systems.

15.
Strategies Trauma Limb Reconstr ; 17(2): 131-135, 2022.
Article in English | MEDLINE | ID: mdl-35990179

ABSTRACT

Aim: This article aims to describe a novel surgical technique for medial malleolar reconstruction in a young child. Background: Severe open ankle injuries that result in bone and soft tissue loss carry a high risk for complications, especially in children who are still growing. These injuries can cause abnormal growth patterns, degenerative diseases, and recurrent instability. Cases of medial malleolar reconstruction have been previously described but none in a child this young. Case description: We present a case of an 13-year-old girl who suffered an open injury to the medial distal tibia with traumatic loss of the medial malleolus at the age of 2 and later suffered a Salter-Harris II fracture to the ipsilateral distal fibula. She presented with varus alignment, a leg length discrepancy, premature asymmetrical growth arrest, chronic non-union of the distal fibula physeal fracture, and severe attenuation of the deltoid ligament. Her secondary deformities were managed with distal fibula osteotomy and fixation, distal tibial hemi-plafond corrective osteotomy, and medial malleolus reconstruction with iliac crest autograft. Her leg length discrepancy was corrected by epiphysiodesis of the contralateral distal femur and proximal tibia. At the 2-year follow-up, the alignment was well maintained, the graft was healing well, and the patient reported no pain and being able to walk and play sports without a brace. Conclusion: Surgical reconstruction of the medial malleolus with correction for abnormal angulation and leg length discrepancies is critical to promoting healthy growth patterns and quality of life for paediatric patients. This severe open ankle injury can be successfully managed by distal fibula osteotomy and fixation, distal tibial intra-articular osteotomy, and medial malleolus reconstruction with iliac crest autograft. Clinical significance: This novel technique is an effective method for the surgical management of paediatric traumatic medial malleolar bone loss in children who are skeletally immature and are at risk of complications due to further growth. How to cite this article: Ponton E, Bakkai A, Courtemanche DJ, et al. Late Ankle Reconstruction in a Child with Remote Traumatic Medial Malleolus Loss: Clinical and Radiographic Outcomes. Strategies Trauma Limb Reconstr 2022;17(2):131-135.

16.
Sci Total Environ ; 837: 155765, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-35533855

ABSTRACT

Returning turfgrass clippings to soil (i.e., mulching) has been shown to yield many benefits, such as reducing fertilizer requirements. However, previous reports on the contribution of clippings to turfgrass fertilization varies widely, making it difficult for turfgrass managers to adjust their fertilization practices. Other potential benefits of this practice, such as soil water conservation, still need to be quantified. The objectives of this project were to measure the contribution of Kentucky bluegrass clippings to N, P and K fertilization under four different N levels and to measure the impact of clippings management on turfgrass color (NDVI), soil nutrient and water content as well as thatch accumulation. A field experiment was conducted over three years, with treatments consisting of two clipping management strategies (returned or removed) and four nitrogen levels (0, 48, 96 and 144 kg N ha -1 yr -1). Clippings were collected on every mowing date and were analyzed for N, P and K foliar content. Soil volumetric water content and NDVI were measured weekly, while thatch accumulation and soil chemical content (Mehlich-3) were assessed twice per year. Increasing N fertilization resulted in an increase in both clippings dry matter yield (DMY) and foliar N concentration. Returning grass clippings was equivalent to doubling the amount of N applied through the fertilizer and resulted in an increase in turfgrass color and soil P and K levels. For P and K, clippings contribution was more affected by their DMY than by foliar concentrations. Grass clippings did not contribute to thatch accumulation, but resulted in a consistent increase (3.9% on average) in soil volumetric water content.


Subject(s)
Nitrogen , Soil , Fertilization , Fertilizers , Nitrogen/analysis , Poaceae , Soil/chemistry , Water
17.
J Sports Sci ; 40(11): 1214-1219, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35501668

ABSTRACT

The aim of this study was to determine whether there are differences in the accuracy and consistency of repeated lawn bowl deliveries between different bowling conditions and to describe the bias of bowls that missed the target (jack). Twenty-seven elite lawn bowl athletes were recruited to partake in the study. Participants delivered 16 bowls in four conditions: (i) forehand and (ii) backhand towards a target 23 metres away and (iii) forehand and (iv) backhand towards a target 27 metres away. The resting position of each bowl relative to the jack was described in terms of absolute displacement, width displacement and length displacement. For each participant and each condition, the average absolute displacement of deliveries was calculated as a measure of accuracy; the average width and length displacement was used to describe the bias of deliveries; and the bivariate variable error of absolute displacement was calculated as a measure of consistency. The forehand towards a target 23 metres away was significantly less accurate and consistent when compared with other conditions. There was a bias for greater width displacement of both forehand deliveries (p < 0.001). Analysing lawn bowls in this detail provides specific areas for coaching to improve lawn bowling performance.


Subject(s)
Sports , Athletes , Biomechanical Phenomena , Humans
18.
Environ Sci Pollut Res Int ; 29(16): 22947-22951, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34508315

ABSTRACT

Deicing reagents are priority soil pollutants in urban ecosystems. Sodium chloride is one of the priority deicing reagents. Sodium chloride is limiting the spread of lawn grass. We first showed the possibility of using environmental biotechnology in urban greening to obtain lawn grasses tolerant of sodium chloride. We have developed a cell selection technology to obtain salt-tolerant lawn grasses. A cell selection scheme with 1% sodium chloride was used. Most of the tested regenerants were more tolerant to NaCl than original plants. The descendants of the studied regenerants demonstrated the preservation of salt resistance. Most of the descendants of the regenerants Agrostis stolonifera retained high decorative qualities under salinity conditions. The tolerance remained in the next five generations. The descendants of the most salt-tolerant clones Agrostis stolonifera demonstrated resistance to 1% sodium chloride concentration in soil. These plants can serve as the basis for the creation of new salt-tolerant varieties.


Subject(s)
Agrostis , Poaceae , Ecosystem , Indicators and Reagents , Salinity , Salt-Tolerant Plants
19.
Insects ; 14(1)2022 Dec 22.
Article in English | MEDLINE | ID: mdl-36661937

ABSTRACT

The tiger beetle, Megacephala carolina carolina L. (Coleoptera: Carabidae), is a common predator in turfgrass and ornamental landscapes in Georgia, USA. Among insecticides used in turfgrass to control foliar and root-feeding insect pests, bifenthrin and imidacloprid are routinely used. It was unclear whether sub-lethal doses of bifenthrin and imidacloprid could cause nontarget effects on larvae and M. carolina carolina adults. Thus, the objective was to determine the sub-lethal effects of bifenthrin and imidacloprid on larvae and M. carolina carolina adults. The results show that M. carolina carolina larvae actively hunt for passing prey by waiting at the hole of the tunnel during the day and nighttime. This larval behavior was affected by sub-lethal doses (up to 25% of full label rate) of bifenthrin but not of imidacloprid. The walking behavior of adult M. carolina carolina was also altered when exposed to sub-lethal doses of bifenthrin as they traveled further distances at greater velocities than the nontreated control. The results imply that turfgrass managers should avoid treating lawns where tiger beetles have actively colonized.

20.
Sensors (Basel) ; 21(16)2021 Aug 05.
Article in English | MEDLINE | ID: mdl-34450732

ABSTRACT

Mobile robots designed for agricultural tasks need to deal with challenging outdoor unstructured environments that usually have dynamic and static obstacles. This assumption significantly limits the number of mapping, path planning, and navigation algorithms to be used in this application. As a representative case, the autonomous lawn mowing robot considered in this work is required to determine the working area and to detect obstacles simultaneously, which is a key feature for its working efficiency and safety. In this context, RGB-D cameras are the optimal solution, providing a scene image including depth data with a compromise between precision and sensor cost. For this reason, the obstacle detection effectiveness and precision depend significantly on the sensors used, and the information processing approach has an impact on the avoidance performance. The study presented in this work aims to determine the obstacle mapping accuracy considering both hardware- and information processing-related uncertainties. The proposed evaluation is based on artificial and real data to compute the accuracy-related performance metrics. The results show that the proposed image and depth data processing pipeline introduces an additional distortion of 38 cm.


Subject(s)
Robotics , Algorithms
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