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To measure the association between statewide adoption of the Centers for Disease Control and Prevention’s (CDC’s) Core Elements for Hospital Antimicrobial Stewardship Programs (Core Elements) and hospital-associated methicillin-resistant Staphylococcus aureus bacteremia (MRSA) and Clostridioides difficile infection (CDI) rates in the United States. We hypothesized that states with a higher percentage of reported compliance with the Core Elements have significantly lower MRSA and CDI rates.
All US states.
Observational longitudinal study.
We used 2014–2016 data from Hospital Compare, Provider of Service files, Medicare cost reports, and the CDC’s Patient Safety Atlas website. Outcomes were MRSA standardized infection ratio (SIR) and CDI SIR. The key explanatory variable was the percentage of hospitals that meet the Core Elements in each state. We estimated state and time fixed-effects models with time-variant controls, and we weighted our analyses for the number of hospitals in the state.
The percentage of hospitals reporting compliance with the Core Elements between 2014 and 2016 increased in all states. A 1% increase in reported ASP compliance was associated with a 0.3% decrease (P < .01) in CDIs in 2016 relative to 2014. We did not find an association for MRSA infections.
Increasing documentation of the Core Elements may be associated with decreases in the CDI SIR. We did not find evidence of such an association for the MRSA SIR, probably due to the short length of the study and variety of stewardship strategies that ASPs may encompass.
SDG 15 requires the maintenance of life on land and endorses priorities already established through international conventions and agreements. The scale, and complexity, of tropical forest loss and biodiversity decline versus the limited resources for conservation and forestry pose many challenges. The main innovation of SDG 15 is that decision makers will see this goal as one to integrate with other SDGs; the risk is that short-term priorities and a ‘business as usual’ approach will undermine this. We examine these opportunities and challenges, the factors that impinge upon them and how they may play out over the next decade. There will be trade-offs between SDG 15 and other SDGs resulting from competition for land, but there are also synergies and opportunities that require recognition. We encourage conservation and development professionals to engage with those responsible for all the Agenda 2030 targets to ensure that SDG 15 is a priority in all SDG related processes.
There is now a strong body of literature showing that bullying victimisation during childhood and adolescence precedes the later development of anxiety and depressive disorders. This study aimed to quantify the burden of anxiety and depressive disorders attributable to experiences of bullying victimisation for the Australian population.
This study updated a previous systematic review summarising the longitudinal association between bullying victimisation and anxiety and depressive disorders. Estimates from eligible studies published from inception until 18 August 2018 were included and meta-analyses were based on quality-effects models. Pooled relative risks were combined with a contemporary prevalence estimate for bullying victimisation for Australia in order to calculate population attributable fractions (PAFs) for the two mental disorder outcomes. PAFs were then applied to estimates of the burden of anxiety and depressive disorders in Australia expressed as disability-adjusted life years (DALYs).
The findings from this study suggest 7.8% of the burden of anxiety disorders and 10.8% of the burden of depressive disorders are attributable to bullying victimisation in Australia. An estimated 30 656 DALYs or 0.52% (95% uncertainty interval 0.33–0.72%) of all DALYs in both sexes and all ages in Australia were attributable to experiences of bullying victimisation in childhood or adolescence.
There is convincing evidence to demonstrate a causal relationship between bullying victimisation and mental disorders. This study showed that bullying victimisation contributes a significant proportion of the burden of anxiety and depressive disorders. The investment and implementation of evidence-based intervention programmes that reduce bullying victimisation in schools could reduce the burden of disease arising from common mental disorders and improve the health of Australians.
Refractory depression is a major contributor to the economic burden of depression. Radically open dialectical behaviour therapy (RO DBT) is an unevaluated new treatment targeting overcontrolled personality, common in refractory depression, but it is not yet known whether the additional expense of RO DBT is good value for money.
To estimate the cost-effectiveness of RO DBT plus treatment as usual (TAU) compared with TAU alone in people with refractory depression (trial registration: ISRCTN85784627).
We undertook a cost-effectiveness analysis alongside a randomised trial evaluating RO DBT plus TAU versus TAU alone for refractory depression in three UK secondary care centres. Our economic evaluation, 12 months after randomisation, adopted the perspective of the UK National Health Service (NHS) and personal social services. It evaluated cost-effectiveness by comparing the net cost of RO DBT with the net gain in quality-adjusted life-years (QALYs), estimated using the EQ-5D-3L measure of health-related quality of life.
The additional cost of RO DBT plus TAU compared with TAU alone was £7048 and was associated with a difference of 0.032 QALYs, yielding an incremental cost-effectiveness ratio (ICER) of £220 250 per QALY. This ICER was well above the National Institute for Health and Care Excellence (NICE) upper threshold of £30 000 per QALY. A cost-effectiveness acceptability curve indicated that RO DBT had a zero probability of being cost-effective compared with TAU at the NICE £30 000 threshold.
In its current resource-intensive form, RO DBT is not a cost-effective use of resources in the UK NHS.
Declaration of interest
R.H. is co-owner and director of Radically Open Ltd, the RO DBT training and dissemination company. D.K. reports grants outside the submitted work from the National Institute for Health Research (NIHR). T.L. receives royalties from New Harbinger Publishing for sales of RO DBT treatment manuals, speaking fees from Radically Open Ltd, and a grant outside the submitted work from the Medical Research Council. He was co-director of Radically Open Ltd between November 2014 and May 2015 and is married to Erica Smith-Lynch, the principal shareholder and one of two directors of Radically Open Ltd. H.O'M. reports personal fees outside the submitted work from the Charlie Waller Institute and Improving Access to Psychological Therapy. S.R. provides RO DBT supervision through her company S C Rushbrook Ltd. I.R. reports grants outside the submitted work from NIHR and Health & Care Research Wales. M. Stanton reports personal fees outside the submitted work from British Isles DBT Training, Stanton Psychological Services Ltd and Taylor & Francis. M. Swales reports personal fees outside the submitted work from British Isles DBT Training, Guilford Press, Oxford University Press and Taylor & Francis. B.W. was co-director of Radically Open Ltd between November 2014 and February 2015.
Individuals with depression often do not respond to medication or psychotherapy. Radically open dialectical behaviour therapy (RO DBT) is a new treatment targeting overcontrolled personality, common in refractory depression.
To compare RO DBT plus treatment as usual (TAU) for refractory depression with TAU alone (trial registration: ISRCTN 85784627).
RO DBT comprised 29 therapy sessions and 27 skills classes over 6 months. Our completed randomised trial evaluated RO DBT for refractory depression over 18 months in three British secondary care centres. Of 250 adult participants, we randomised 162 (65%) to RO DBT. The primary outcome was the Hamilton Rating Scale for Depression (HRSD), assessed masked and analysed by treatment allocated.
After 7 months, immediately following therapy, RO DBT had significantly reduced depressive symptoms by 5.40 points on the HRSD relative to TAU (95% CI 0.94–9.85). After 12 months (primary end-point), the difference of 2.15 points on the HRSD in favour of RO DBT was not significant (95% CI –2.28 to 6.59); nor was that of 1.69 points on the HRSD at 18 months (95% CI –2.84 to 6.22). Throughout RO DBT participants reported significantly better psychological flexibility and emotional coping than controls. However, they reported eight possible serious adverse reactions compared with none in the control group.
The RO DBT group reported significantly lower HRSD scores than the control group after 7 months, but not thereafter. The imbalance in serious adverse reactions was probably because of the controls' limited opportunities to report these.
Declaration of interest
Six of the 16 authors have received royalties or fees for RO DBT. R.J.H. is co-owner and director of Radically Open Ltd, the RO DBT training and dissemination company. D.K. reports grants outside the submitted work from NIHR. T.R.L. receives royalties from New Harbinger Publishing for sales of RO DBT treatment manuals, speaking fees from Radically Open Ltd and a grant outside the submitted work from the Medical Research Council. He was codirector of Radically Open Ltd between November 2014 and May 2015 and is married to Erica Smith-Lynch, the principal shareholder and one of two current directors of Radically Open Ltd. H.O’M. reports personal fees from the Charlie Waller Institute and Improving Access to Psychological Therapy. S.C.R. provides RO DBT supervision through S C Rushbrook Ltd. I.T.R. reports grants outside the submitted work from NIHR and Health & Care Research Wales. M.St. reports personal fees from British Isles DBT Training, Stanton Psychological Services Ltd, and Taylor & Francis Ltd. M.Sw. reports personal fees from British Isles DBT Training, Guilford Press, Oxford University Press and Taylor & Francis Ltd. B.W. was codirector of Radically Open Ltd between November 2014 and February 2015.
To sustainably improve cleaning of high-touch surfaces (HTSs) in acute-care hospitals using a multimodal approach to education, reduction of barriers to cleaning, and culture change for environmental services workers.
The study was conducted in 2 academic acute-care hospitals, 2 community hospitals, and an academic pediatric and women’s hospital.
Frontline environmental services workers.
A 5-module educational program, using principles of adult learning theory, was developed and presented to environmental services workers. Audience response system (ARS), videos, demonstrations, role playing, and graphics were used to illustrate concepts of and the rationale for infection prevention strategies. Topics included hand hygiene, isolation precautions, personal protective equipment (PPE), cleaning protocols, and strategies to overcome barriers. Program evaluation included ARS questions, written evaluations, and objective assessments of occupied patient room cleaning. Changes in hospital-onset C. difficile infection (CDI) and methicillin-resistant S. aureus (MRSA) bacteremia were evaluated.
On average, 357 environmental service workers participated in each module. Most (93%) rated the presentations as ‘excellent’ or ‘very good’ and agreed that they were useful (95%), reported that they were more comfortable donning/doffing PPE (91%) and performing hand hygiene (96%) and better understood the importance of disinfecting HTSs (96%) after the program. The frequency of cleaning individual HTSs in occupied rooms increased from 26% to 62% (P < .001) following the intervention. Improvement was sustained 1-year post intervention (P < .001). A significant decrease in CDI was associated with the program.
A novel program that addressed environmental services workers’ knowledge gaps, challenges, and barriers was well received and appeared to result in learning, behavior change, and sustained improvements in cleaning.
To compare risk of surgical site infection (SSI) following cesarean delivery between women covered by Medicaid and private health insurance.
Cesarean deliveries covered by Medicaid or private insurance and reported to the National Healthcare Safety Network (NHSN) and state inpatient discharge databases by hospitals in California (2011–2013).
Deliveries reported to NHSN and state inpatient discharge databases were linked to identify SSIs in the 30 days following cesarean delivery, primary payer, and patient and procedure characteristics. Additional hospital-level characteristics were obtained from public databases. Relative risk of SSI by primary payer primary payer was assessed using multivariable logistic regression adjusting for patient, procedure, and hospital characteristics, accounting for facility-level clustering.
Of 291,757 cesarean deliveries included, 48% were covered by Medicaid. SSIs were detected following 1,055 deliveries covered by Medicaid (0.75%) and 955 deliveries covered by private insurance (0.63%) (unadjusted odds ratio, 1.2; 95% confidence interval [CI], 1.1–1.3; P < .0001). The adjusted odds of SSI following cesarean deliveries covered by Medicaid was 1.4 (95% CI, 1.2–1.6; P < .0001) times the odds of those covered by private insurance.
In this, the largest and only multicenter study to investigate SSI risk following cesarean delivery by primary payer, Medicaid-insured women had a higher risk of infection than privately insured women. These findings suggest the need to evaluate and better characterize the quality of maternal healthcare for and needs of women covered by Medicaid to inform targeted infection prevention and policy.
Breakthrough Listen is a 10-yr initiative to search for signatures of technologies created by extraterrestrial civilisations at radio and optical wavelengths. Here, we detail the digital data recording system deployed for Breakthrough Listen observations at the 64-m aperture CSIRO Parkes Telescope in New South Wales, Australia. The recording system currently implements two modes: a dual-polarisation, 1.125-GHz bandwidth mode for single-beam observations, and a 26-input, 308-MHz bandwidth mode for the 21-cm multibeam receiver. The system is also designed to support a 3-GHz single-beam mode for the forthcoming Parkes ultra-wideband feed. In this paper, we present details of the system architecture, provide an overview of hardware and software, and present initial performance results.
Herbicide active ingredients, formulation type, ambient temperature, and humidity can influence volatility. A method was developed using volatility chambers to compare relative volatility of different synthetic auxin herbicide formulations in controlled environments. 2,4-D or dicamba acid vapors emanating after application were captured in air-sampling tubes at 24, 48, 72, and 96 h after herbicide application. The 2,4-D or dicamba was extracted from sample tubes and quantified using liquid chromatography and tandem mass spectrometry. Volatility from 2,4-D dimethylamine (DMA) was determined to be greater than that of 2,4-D choline in chambers where temperatures were held at 30 or 40 C and relative humidity (RH) was 20% or 50%. Air concentration of 2,4-D DMA was 0.399 µg m−3 at 40 C and 20% RH compared with 0.005 µg m−3 for 2,4-D choline at the same temperature and humidity at 24 h after application. Volatility from 2,4-D DMA and 2,4-D choline increased as temperature increased from 30 to 40 C. However, volatility from 2,4-D choline was lower than observed from 2,4-D DMA. Volatility from 2,4-D choline at 40 C increased from 0.00458 to 0.0263 µg m−3 and from 0.00341 to 0.025 µg m−3 when humidity increased from 20% to 50% at 72 and 96 h after treatment, respectively, whereas, volatility from 2,4-D DMA tended to be higher at 20% RH compared with 50% RH. Air concentration of dicamba diglycolamine was similar at all time points when measured at 40 C and 20% RH. By 96 h after treatment, there was a trend for lower air concentration of dicamba compared with earlier timings. This method using volatility chambers provided good repeatability with low variability across replications, experiments, and herbicides.
The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
Antineuronal antibodies are associated with psychosis, although their clinical significance in first episode of psychosis (FEP) is undetermined.
To examine all patients admitted for treatment of FEP for antineuronal antibodies and describe clinical presentations and treatment outcomes in those who were antibody positive.
Individuals admitted for FEP to six mental health units in Queensland, Australia, were prospectively tested for serum antineuronal antibodies. Antibody-positive patients were referred for neurological and immunological assessment and therapy.
Of 113 consenting participants, six had antineuronal antibodies (anti-N-methyl-D-aspartate receptor antibodies [n = 4], voltage-gated potassium channel antibodies [n = 1] and antibodies against uncharacterised antigen [n = 1]). Five received immunotherapy, which prompted resolution of psychosis in four.
A small subgroup of patients admitted to hospital with FEP have antineuronal antibodies detectable in serum and are responsive to immunotherapy. Early diagnosis and treatment is critical to optimise recovery.
Objectives: To evaluate prospective and retrospective memory abilities in Operation Enduring Freedom (OEF), Operation Iraqi Freedom (OIF), and Operation New Dawn (OND) Veterans with and without a self-reported history of blast-related mild traumatic brain injury (mTBI). Methods: Sixty-one OEF/OIF/OND Veterans, including Veterans with a self-reported history of blast-related mTBI (mTBI group; n=42) and Veterans without a self-reported history of TBI (control group; n=19) completed the Memory for Intentions Test, a measure of prospective memory (PM), and two measures of retrospective memory (RM), the California Verbal Learning Test-II and the Brief Visuospatial Memory Test-Revised. Results: Veterans in the mTBI group exhibited significantly lower PM performance than the control group, but the groups did not differ in their performance on RM measures. Further analysis revealed that Veterans in the mTBI group with current PTSD (mTBI/PTSD+) demonstrated significantly lower performance on the PM measure than Veterans in the control group. PM performance by Veterans in the mTBI group without current PTSD (mTBI/PTSD-) was intermediate between the mTBI/PTSD+ and control groups, and results for the mTBI/PTSD- group were not significantly different from either of the other two groups. Conclusions: Results suggest that PM performance may be a sensitive marker of cognitive dysfunction among OEF/OIF/OND Veterans with a history of self-reported blast-related mTBI and comorbid PTSD. Reduced PM may account, in part, for complaints of cognitive difficulties in this Veteran cohort, even years post-injury. (JINS, 2018, 24, 324–334)
The Yellow Sea region is of high global importance for waterbird populations, but recent systematic bird count data enabling identification of the most important sites are relatively sparse for some areas. Surveys of waterbirds at three sites on the coast of southern Jiangsu Province, China, in 2014 and 2015 produced peak counts of international importance for 24 species, including seven globally threatened and six Near Threatened species. The area is of particular global importance for the ‘Critically Endangered’ Spoon-billed Sandpiper Calidris pygmaea (peak count across all three study sites: 62 in spring  and 225 in autumn  and ‘Endangered’ Spotted Greenshank Tringa guttifer (peak count across all three study sites: 210 in spring  and 1,110 in autumn ). The southern Jiangsu coast is therefore currently the most important migratory stopover area in the world, in both spring and autumn, for both species. Several serious and acute threats to waterbirds were recorded at these study sites. Paramount is the threat of large-scale land claim which would completely destroy intertidal mudflats of critical importance to waterbirds. Degradation of intertidal mudflat habitats through the spread of invasive Spartina, and mortality of waterbirds by entrapment in nets or deliberate poisoning are also real and present serious threats here. Collisions with, and displacement by, wind turbines and other structures, and industrial chemical pollution may represent additional potential threats. We recommend the rapid establishment of effective protected areas for waterbirds in the study area, maintaining large areas of open intertidal mudflat, and the urgent removal of all serious threats currently faced by waterbirds here.
X-ray fluorescence (XRF) has been employed as one of several orthogonal means of screening materials to prevent counterfeit and adulterated products from entering the product stream. We document the use of principal component analysis (PCA) of XRF data on compositionally similar and dissimilar stainless steels for the purpose of testing the feasibility of employing XRF spectra to parse and bin these alloys as the same or significantly different alloy materials. The results indicate that XRF spectra can separate and assign alloys via PCA, but that important corrections for detector drift and scaling must be performed in order to achieve valid results.
The spatial and temporal development of shear-induced overturning billows associated with breaking internal solitary waves is studied by means of a combined laboratory and numerical investigation. The waves are generated in the laboratory by a lock exchange mechanism and they are simulated numerically via a contour-advective semi-Lagrangian method. The properties of individual billows (maximum height attained, time of collapse, growth rate, speed, wavelength, Thorpe scale) are determined in each case, and the billow interaction processes are studied and classified. For broad flat waves, similar characteristics are seen to those in parallel shear flow, but, for waves not at the conjugate flow limit, billow characteristics are affected by the spatially varying wave-induced shear flow. Wave steepness and wave amplitude are shown to have a crucial influence on determining the type of interaction that occurs between billows and whether billow overturning can be arrested. Examples are given in which billows (i) evolve independently of one another, (ii) pair with one another, (iii) engulf/entrain one another and (iv) fail to completely overturn. It is shown that the vertical extent a billow can attain (and the associated Thorpe scale of the billow) is dependent on wave amplitude but that its value saturates once a given amplitude is reached. It is interesting to note that this amplitude is less than the conjugate flow limit amplitude. The number of billows that form on a wave is shown to be dependent on wavelength; shorter waves support fewer but larger billows than their long-wave counterparts for a given stratification.
Background: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a recently described life-threatening autoimmune disorder associated with a characteristic multi-stage neuropsychiatric syndrome. Although it is known that the majority of patients experience neuropsychological disturbance post-treatment, some aspects of the cognitive profile remain unclear. Methods: This study sought to investigate patterns of cognitive functioning in a sample of anti-NMDAR encephalitis patients. Seven (6F:1M; mean age, 26.4 years; range, 16–37 years) treated patients completed a comprehensive set of neurocognitive and social functioning measures. Performance was analyzed using normative data (where available), and comparison with matched controls (10F:4M; mean age, 25.8 years; range, 16–38 years). Results: Individual cognitive profiles ranged from within normal limits to extensive dysfunction. Relative to controls, the patient group’s performance was affected in the domains of verbal/ visual memory, working memory, attention, processing speed, executive functioning, and social cognition. The patient group also reported significantly higher levels of anxiety compared to controls. Conclusions: These results add to the accumulating evidence that neurocognitive deficits, consistent with the distribution and functions of the NMDAR system can persist during recovery from anti-NMDAR encephalitis. This is the first study to provide evidence of performance decrements on measures of social cognition, including some involving theory of mind. (JINS, 2016, 22, 828–838)
The relationship between the duration of depressive symptoms and mortality remains poorly understood.
To examine whether the duration of depressive symptoms is associated with mortality risk.
Data (n = 9560) came from the English Longitudinal Study of Ageing (ELSA). We assessed depressive symptom duration as the sum of examinations with an eight-item Center for Epidemiologic Studies Depression Scale score of ⩾3; we ascertained mortality from linking our data to a national register.
Relative to those participants who never reported symptoms, the age- and gender-adjusted hazard ratios for elevated depressive symptoms over 1, 2, 3 and 4 examinations were 1.41 (95% CI 1.15–1.74), 1.80 (95% CI 1.44–2.26), 1.97 (95% CI 1.57–2.47) and 2.48 (95% CI 1.90–3.23), respectively (P for trend <0.001). This graded association can be explained largely by differences in physical activity, cognitive function, functional impairments and physical illness.
In this cohort of older adults, the duration of depressive symptoms was associated with mortality in a dose–response manner.
The collective response of electrons in an ultrathin foil target irradiated by an ultraintense (
) laser pulse is investigated experimentally and via 3D particle-in-cell simulations. It is shown that if the target is sufficiently thin that the laser induces significant radiation pressure, but not thin enough to become relativistically transparent to the laser light, the resulting relativistic electron beam is elliptical, with the major axis of the ellipse directed along the laser polarization axis. When the target thickness is decreased such that it becomes relativistically transparent early in the interaction with the laser pulse, diffraction of the transmitted laser light occurs through a so called ‘relativistic plasma aperture’, inducing structure in the spatial-intensity profile of the beam of energetic electrons. It is shown that the electron beam profile can be modified by variation of the target thickness and degree of ellipticity in the laser polarization.
Crop rotation promotes productivity, nutrient cycling, and effective pest
management. However, in row-crop systems, rotation is frequently limited to
two crops. Adding a third crop, especially a perennial crop, might increase
crop-rotation benefits, but concerns about disruption of agricultural and
ecological processes preclude grower adoption of a three-crop rotation. The
objective of the present research was to determine whether weed seed banks
differ between a sod-based rotation (bahiagrass–bahiagrass–peanut–cotton)
and a conventional peanut–cotton rotation (peanut–cotton–cotton) and the
importance of crop phase in weed seed-bank dynamics in a long-term
experiment initiated in 1999 in Florida. Extractable (ESB) and germinable
(GSB) seed banks were evaluated at the end of each crop phase in 2012 and
2013, and total weed seed or seedling number, Shannon-Weiner's diversity
(H′), richness, and evenness were determined. ESB
increased in H′ (36%), richness (29%), and total number of
weed seeds (40%) for sod-based compared with conventional rotation, whereas
GSB increased 32% in H′, 27% in richness, and 177% in total
number of weed seedlings. Crop phase was a determinant factor in the
differences between crop rotations. The first year of bahiagrass (B1)
exhibited increases in weed seed and seedling number, H′,
and richness and had the highest values observed in the sod-based rotation.
These increases were transient, and in the second year of bahiagrass (B2),
weed numbers and H′ decreased and reached levels equivalent
to those in the conventional peanut–cotton rotation. The B1 phase increased
the germinable fraction of the seed bank, compared with the other crop
phases, but not the total number of weed seeds as determined by ESB. The
increases in H′ and richness in bahiagrass phases were
mainly due to grass weed species. However, these grass weed species were not
associated with peanut and cotton phases of the sod-based rotation. The
results of the present study demonstrated that including bahiagrass as a
third crop in a peanut–cotton rotation could increase weed community
diversity, mainly by favoring increases in richness and diversity, but the
structure and characteristics of the rotation would prevent continuous
increases in the weed seed bank that could affect the peanut and cotton