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OBJECTIVES: The goals of this retrospective study were to assess the clinical and radiographic outcomes in dogs with proximal femoral fractures, other than capital physeal fractures, treated via total hip arthroplasty. MATERIALS AND METHODS: Medical records as well as pre-operative, immediate post-operative and 2 to 3 months post-operative radiographs of 14 dogs with femoral head and neck fractures treated via total hip arthroplasty were reviewed. A Liverpool Osteoarthritis in Dogs questionnaire was completed by owners to assess long-term outcomes. RESULTS: Seven femoral head fractures, and seven femoral neck fractures were included. Four of the femoral head fractures were acute in nature, the three remaining femoral head fractures and all seven femoral neck fracture cases were chronic fractures. Malorientation of the femoral stem was more common in the chronic femoral fracture cases when compared to the acute femoral fracture cases. Two of the acute fracture cases and five chronic fracture cases experienced a change in femoral stem position post-operatively. One femoral fissure fracture occurred and was repaired intraoperatively. One case had a post-operative complication that resulted in implant removal. All dogs had good to excellent owner-perceived outcome. CLINICAL SIGNIFICANCE: Femoral head and neck fractures, and in particular the chronic cases, represented a challenging subset of cases presenting for total hip arthroplasty, resulting in suboptimal stem alignment in many cases. However, clinical outcomes were considered good to excellent in all dogs in the study, indicating that total hip arthroplasty is a viable treatment option for these types of fractures.
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INTRODUCTION: Exposure factor selection influences ionising radiation dose and image quality in projection radiography. Radiographers have a duty to comply with legislation, ensuring doses (resulting from exposure factor selection) are kept ALARP. Hence, this paper aims to explore variation in patient habitus perceptions among final-year student radiographers and any influence on imparted dose due to exposure factor selection. METHODS: Institutional ethics was granted. Student radiographers engaged in a 2-stage primary research study. Students were asked to select exposure factors (kVp and mAs values) and the most appropriate BMI category for several models undergoing a routine anteroposterior abdomen projection. Monte-Carlo simulation software was utilised to establish the absorbed and effective dose for these exposures. SPSS software was used to conduct statistical analysis of this data. RESULTS: A response rate of 19% (n = 14) was recorded. The findings identified variation in habitus perception with greater variation among female models. (p = 0.002). There was significant variation in exposure factor selection and ionising radiation dose, particularly between the male and female models. There was a significant difference between the healthy, overweight, and obese female models for absorbed (p = 0.032) and effective dose (p = 0.032) but not for the male models. CONCLUSION: There was a distinct difficulty recognising overweight and obese models and inconsistency regarding the selection of exposure factors. It was concluded that male models were more likely to receive a greater dose than females due to higher proposed exposure factors. IMPLICATIONS FOR PRACTICE: This study adds to the existing evidence base, providing insight into the perceptions of radiography students and the effect on exposure factor selection. This study will likely stand as a baseline for further investigation into competency levels among qualified radiographers to improve radiation protection.
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Doses de Radiação , Humanos , Feminino , Masculino , Método de Monte Carlo , Percepção , Índice de Massa CorporalRESUMO
BACKGROUND AND OBJECTIVE: Predicting the duration of surgical procedures is an important step in scheduling operating rooms. Many factors have been shown to influence the duration of a procedure, in this research we aim to use medical ontological information to improve the predictions. METHODS: This paper presents two methods for incorporating the medical information about a surgical procedure into the prediction of the duration of the procedure. The first method uses the Systematised Nomenclature of Medicine Clinical Terms to relate different procedures to each other. The second uses simple text fragments. The relationships between types of procedures are included in a regression model for the procedure duration. These methods are applied to data from New Zealand healthcare facilities and the accuracy of the estimations of the durations is compared. In addition a simulation of scheduling the procedures in an operating room is performed. RESULTS: It is shown that both of the methods provide an improvement in the prediction of procedure durations. When compared to a traditional categorical encoding, the ontological information provides an improvement in the continuous ranked probability scores of the prediction of procedure durations from 18.4 min to 17.1 min, and from 25.3 to 21.3 min for types of procedures that are not performed very often. CONCLUSIONS: Different methods for encoding medical ontological information in surgery procedure duration predictions are presented, and show an improvement over traditional models. The improvement in duration prediction is shown to improve the efficiency of scheduling in a simple simulation.
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Salas Cirúrgicas , Simulação por Computador , ProbabilidadeRESUMO
We describe an analysis comparing the pp[over ¯] elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in pp collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM cross sections, extrapolated to a center-of-mass energy of sqrt[s]=1.96 TeV, are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the pp cross section. The two data sets disagree at the 3.4σ level and thus provide evidence for the t-channel exchange of a colorless, C-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same C-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scattering amplitude in pp scattering for which the significance is between 3.4σ and 4.6σ. The combined significance is larger than 5σ and is interpreted as the first observation of the exchange of a colorless, C-odd gluonic compound.
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BACKGROUND: Pneumococcal carriage studies provide a baseline for measuring the impact of pneumococcal conjugate vaccines (PCVs). The advent of conjugate vaccines has led to reductions in vaccine serotypes (VTs) in pneumococcal carriage. However, increasing non-vaccine serotypes (NVTs) remain a significant concern, necessitating continued surveillance of serotypes in the 13-valent PCV vaccine (PCV13) era. OBJECTIVES: To investigate pneumococcal carriage, serotype distribution and risk factors for pneumococcal colonisation among children presenting for routine immunisation at two clinics in Gauteng Province, South Africa (SA), 10 years after PCV introduction into the SA Expanded Programme on Immunisation (EPI-SA). METHODS: Nasopharyngeal swabs were collected from 322 healthy children aged between 6 weeks and 5 years at two clinic centres in 2014 and 2016. Demographic data, risk factors for colonisation and vaccination details were recorded. The pneumococcal isolates were serotyped and tested for antimicrobial susceptibility. RESULTS: Pneumococci were isolated from 138/316 healthy children (43.7%) presenting for routine immunisation at two clinics. The median age was 8.3 months and the age range 1.4 months - 5 years. Carriage varied across the age groups: 6 - 14 weeks 35.5%, 9 months 27.5%, 18 months 21.7%, and 5 years 15.2%. Risk factors significantly associated with pneumococcal colonisation included young age (9 - 18 months (odds ratio OR 3.5; 95% confidence interval (CI) 1.9 - 5.9), type of dwelling (single room (OR 8.1; 95% CI 1.3 - 52.3) or informal dwelling (OR 2.4; 95% CI 1.2 - 4.5)) and Haemophilus influenzae carriage (OR 5.6; 95% CI 0.6 - 2.5). Of the 26 serotypes detected, 19F (10/121; 8.3%) was the most frequent. The most frequent NVTs were 23B (16/121; 13.2%), 15B/C (14/121; 11.6 %) and 35B (11/121; 8.2%). Children aged 9 months carried the highest proportion of NVTs (33/101; 32.7%). Penicillin non-susceptibility was observed in 20 NVT isolates (20/36; 55.6%) and 2 VT isolates (2/36; 5.6%). CONCLUSIONS: The pneumococcal carriage prevalence described in our study varied across the age groups and was lower compared with other African studies that looked at pneumococcal carriage post PCV. The study gave insight into the common NVTs encountered at two immunisation clinics in Gauteng. Given that pneumococcal carriage precedes disease, common colonisers such as 15B/C and 35B may be sufficiently prevalent in carriage for expansion to result in significant disease replacement.
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Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Infecções Pneumocócicas/epidemiologia , Vacinas Pneumocócicas/provisão & distribuição , Vacinação/estatística & dados numéricos , Criança , Pré-Escolar , Humanos , Lactente , Nasofaringe/microbiologia , Infecções Pneumocócicas/prevenção & controle , Prevalência , África do Sul , Streptococcus pneumoniae/isolamento & purificaçãoRESUMO
Malaria, caused by Plasmodium parasites, continues to be a devastating global health issue. Despite a decline in malaria related deaths over the last decade, overall progress has plateaued. Key challenges to malaria prevention and control include the lack of a broadly effective vaccine and parasite drug resistance, including to the current gold standard artemisinin combination therapies (ACTs). New drugs with unique modes of action are therefore a priority for both the treatment and prevention of malaria. Unlike treatment drugs which need to kill parasites quickly to reduce or prevent clinical symptoms, compounds that kill parasites more slowly may be an option for malaria prevention. Natural products and natural product derived compounds have historically been an excellent source of antimalarial drugs, including the artemisinin component of ACTs. In this study, 424 natural product derived compounds were screened for in vitro activity against P. falciparum in assays designed to detect slow action activity, with 46 hit compounds identified as having >50% inhibition at 10 µM. Dose response assays revealed nine compounds with submicromolar activity, with slow action activity confirmed for two compounds, alstonine and himbeline (50% inhibitory concentration (IC50) 0.17 and 0.58 µM, respectively). Both compounds displayed >140-fold better activity against P. falciparum versus two human cell lines (Selectivity Index (SI) >1,111 and > 144, respectively). Importantly, P. falciparum multi-drug resistant lines showed no cross-resistance to alstonine or himbeline, with some resistant lines being more sensitive to these two compounds compared to the drug sensitive line. In addition, alstonine displayed cross-species activity against the zoonotic species, P. knowelsi (IC50 ~1 µM). Outcomes of this study provide a starting point for further investigations into these compounds as antiplasmodial drug candidates and the investigation of their molecular targets.
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Antimaláricos , Produtos Biológicos , Malária Falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Humanos , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum , Alcaloides de Triptamina e SecologaninaRESUMO
OBJECTIVE: Physical exercise may serve as a protective factor for posttraumatic stress disorder (PTSD), but little is known about whether physical exercise is associated with PTSD in population-based samples of military veterans. METHODS: We analyzed cross-sectional data on the relation between self-reported physical exercise frequency and the prevalence of probable PTSD in a nationally representative sample of 2832 U.S. military veterans who participated in the National Health and Resilience in Veterans Study. RESULTS: A "U-shaped" association best explained the relation between self-reported exercise frequency and the prevalence of probable PTSD. Compared to veterans without probable PTSD, those with probable PTSD were nearly twice as likely to report no weekly exercise (52.3% vs. 29.3%) or daily (7 days/week) exercise (15.2% vs. 8.5%) and were nearly half as likely to report exercising a median of 3.5 days/week (32.6% vs. 62.1%). No exercise was associated with greater severity of emotional numbing and lower severity of anxious arousal symptoms, while daily exercise was associated with greater severity of re-experiencing symptoms. CONCLUSIONS: Results of this study suggest a "U-shaped" association between self-reported exercise frequency and the prevalence of probable PTSD among U.S. veterans. Veterans with probable PTSD were more likely than those without probable PTSD to report not exercising at all or exercising every day and were less likely to report exercising 1-6 days per week. Clinical implications of these findings are discussed.
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Exercício Físico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Veteranos/psicologia , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Autorrelato , Transtornos de Estresse Pós-Traumáticos/psicologia , Estados Unidos/epidemiologia , Veteranos/estatística & dados numéricosRESUMO
High-flow nasal oxygen is increasingly used in complex head and neck surgical procedures and difficult airway management. We describe a case where an operating room fire occurred while using high-flow nasal oxygen during an awake tracheostomy for an obese patient in airway extremis due to supraglottitis. Shortly after the operation began, and before incision of the trachea, electrical diathermy applied to bleeding sub-cutaneous vessels ignited a small flame. This was extinguished without harm to the patient and the procedure was completed without further complication. Fire requires three components: fuel; heat; and an oxidiser. We speculate that high-flow oxygen channelled under the drapes and acted as the oxidiser; either tissue eschar or vapourised fat were the fuel; and the diathermy supplied a source of ignition to complete the fire triad. When using high flows of concentrated oxygen, practitioners should aim to minimise all of these factors and be alert for the risk of fire at every stage of the operation.
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The recent discovery by Advanced LIGO and Advanced Virgo of a gravitational wave signal from a binary neutron star inspiral has enabled tests of general relativity (GR) with this new type of source. This source, for the first time, permits tests of strong-field dynamics of compact binaries in the presence of matter. In this Letter, we place constraints on the dipole radiation and possible deviations from GR in the post-Newtonian coefficients that govern the inspiral regime. Bounds on modified dispersion of gravitational waves are obtained; in combination with information from the observed electromagnetic counterpart we can also constrain effects due to large extra dimensions. Finally, the polarization content of the gravitational wave signal is studied. The results of all tests performed here show good agreement with GR.
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We analyze the impact of a proposed tidal instability coupling p modes and g modes within neutron stars on GW170817. This nonresonant instability transfers energy from the orbit of the binary to internal modes of the stars, accelerating the gravitational-wave driven inspiral. We model the impact of this instability on the phasing of the gravitational wave signal using three parameters per star: an overall amplitude, a saturation frequency, and a spectral index. Incorporating these additional parameters, we compute the Bayes factor (lnB_{!pg}^{pg}) comparing our p-g model to a standard one. We find that the observed signal is consistent with waveform models that neglect p-g effects, with lnB_{!pg}^{pg}=0.03_{-0.58}^{+0.70} (maximum a posteriori and 90% credible region). By injecting simulated signals that do not include p-g effects and recovering them with the p-g model, we show that there is a ≃50% probability of obtaining similar lnB_{!pg}^{pg} even when p-g effects are absent. We find that the p-g amplitude for 1.4 M_{â} neutron stars is constrained to less than a few tenths of the theoretical maximum, with maxima a posteriori near one-tenth this maximum and p-g saturation frequency â¼70 Hz. This suggests that there are less than a few hundred excited modes, assuming they all saturate by wave breaking. For comparison, theoretical upper bounds suggest â²10^{3} modes saturate by wave breaking. Thus, the measured constraints only rule out extreme values of the p-g parameters. They also imply that the instability dissipates â²10^{51} erg over the entire inspiral, i.e., less than a few percent of the energy radiated as gravitational waves.
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Oxygen minimum zones (OMZs), large midwater regions of very low oxygen, are expected to expand as a result of climate change. While oxygen is known to be important in structuring midwater ecosystems, a precise and mechanistic understanding of the effects of oxygen on zooplankton is lacking. Zooplankton are important components of midwater food webs and biogeochemical cycles. Here, we show that, in the eastern tropical North Pacific OMZ, previously undescribed submesoscale oxygen variability has a direct effect on the distribution of many major zooplankton groups. Despite extraordinary hypoxia tolerance, many zooplankton live near their physiological limits and respond to slight (≤1%) changes in oxygen. Ocean oxygen loss (deoxygenation) may, thus, elicit major unanticipated changes to midwater ecosystem structure and function.
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Oxigênio/química , Água do Mar/química , Zooplâncton/fisiologia , Adaptação Fisiológica , Animais , Respiração Celular , Mudança Climática , Ecossistema , Cadeia Alimentar , Hipóxia , Oceanos e Mares , Oxigênio/metabolismoRESUMO
We present the first Advanced LIGO and Advanced Virgo search for ultracompact binary systems with component masses between 0.2 M_{â}-1.0 M_{â} using data taken between September 12, 2015 and January 19, 2016. We find no viable gravitational wave candidates. Our null result constrains the coalescence rate of monochromatic (delta function) distributions of nonspinning (0.2 M_{â}, 0.2 M_{â}) ultracompact binaries to be less than 1.0×10^{6} Gpc^{-3} yr^{-1} and the coalescence rate of a similar distribution of (1.0 M_{â}, 1.0 M_{â}) ultracompact binaries to be less than 1.9×10^{4} Gpc^{-3} yr^{-1} (at 90% confidence). Neither black holes nor neutron stars are expected to form below â¼1 M_{â} through conventional stellar evolution, though it has been proposed that similarly low mass black holes could be formed primordially through density fluctuations in the early Universe and contribute to the dark matter density. The interpretation of our constraints in the primordial black hole dark matter paradigm is highly model dependent; however, under a particular primordial black hole binary formation scenario we constrain monochromatic primordial black hole populations of 0.2 M_{â} to be less than 33% of the total dark matter density and monochromatic populations of 1.0 M_{â} to be less than 5% of the dark matter density. The latter strengthens the presently placed bounds from microlensing surveys of massive compact halo objects (MACHOs) provided by the MACHO and EROS Collaborations.
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On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were neutron stars that are described by the same equation of state and have spins within the range observed in Galactic binary neutron stars. Our analysis employs two methods: the use of equation-of-state-insensitive relations between various macroscopic properties of the neutron stars and the use of an efficient parametrization of the defining function p(ρ) of the equation of state itself. From the LIGO and Virgo data alone and the first method, we measure the two neutron star radii as R_{1}=10.8_{-1.7}^{+2.0} km for the heavier star and R_{2}=10.7_{-1.5}^{+2.1} km for the lighter star at the 90% credible level. If we additionally require that the equation of state supports neutron stars with masses larger than 1.97 M_{â} as required from electromagnetic observations and employ the equation-of-state parametrization, we further constrain R_{1}=11.9_{-1.4}^{+1.4} km and R_{2}=11.9_{-1.4}^{+1.4} km at the 90% credible level. Finally, we obtain constraints on p(ρ) at supranuclear densities, with pressure at twice nuclear saturation density measured at 3.5_{-1.7}^{+2.7}×10^{34} dyn cm^{-2} at the 90% level.
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We report high-precision small-angle neutron scattering of the orientation of the Skyrmion lattice in a spherical sample of MnSi under systematic changes of the magnetic field direction. For all field directions the Skyrmion lattice may be accurately described as a triple-Q[over â] state, where the modulus |Q[over â]| is constant and the wave vectors enclose rigid angles of 120°. Along a great circle across ⟨100⟩, ⟨110⟩, and ⟨111⟩ the normal to the Skyrmion-lattice plane varies systematically by ±3° with respect to the field direction, while the in-plane alignment displays a reorientation by 15° for magnetic field along ⟨100⟩. Our observations are qualitatively and quantitatively in excellent agreement with an effective potential, which is determined by the symmetries of the tetrahedral point group T and includes contributions up to sixth order in spin-orbit coupling, providing a full account of the effect of cubic magnetocrystalline anisotropies on the Skyrmion lattice in MnSi.
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We present a measurement of the effective weak mixing angle parameter sin^{2}θ_{eff}^{â} in pp[over ¯]âZ/γ^{*}âµ^{+}µ^{-} events at a center-of-mass energy of 1.96 TeV, collected by the D0 detector at the Fermilab Tevatron Collider and corresponding to 8.6 fb^{-1} of integrated luminosity. The measured value of sin^{2}θ_{eff}^{â}[µµ]=0.23016±0.00064 is further combined with the result from the D0 measurement in pp[over ¯]âZ/γ^{*}âe^{+}e^{-} events, resulting in sin^{2}θ_{eff}^{â}[comb]=0.23095±0.00040. This combined result is the most precise measurement from a single experiment at a hadron collider and is the most precise determination using the coupling of the Z/γ^{*} to light quarks.
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The detection of gravitational waves with Advanced LIGO and Advanced Virgo has enabled novel tests of general relativity, including direct study of the polarization of gravitational waves. While general relativity allows for only two tensor gravitational-wave polarizations, general metric theories can additionally predict two vector and two scalar polarizations. The polarization of gravitational waves is encoded in the spectral shape of the stochastic gravitational-wave background, formed by the superposition of cosmological and individually unresolved astrophysical sources. Using data recorded by Advanced LIGO during its first observing run, we search for a stochastic background of generically polarized gravitational waves. We find no evidence for a background of any polarization, and place the first direct bounds on the contributions of vector and scalar polarizations to the stochastic background. Under log-uniform priors for the energy in each polarization, we limit the energy densities of tensor, vector, and scalar modes at 95% credibility to Ω_{0}^{T}<5.58×10^{-8}, Ω_{0}^{V}<6.35×10^{-8}, and Ω_{0}^{S}<1.08×10^{-7} at a reference frequency f_{0}=25 Hz.
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We present possible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitational-wave transients, with particular focus on gravitational-wave signals from the inspiral of binary neutron star systems, which are the most promising targets for multi-messenger astronomy. The ability to localize the sources of the detected signals depends on the geographical distribution of the detectors and their relative sensitivity, and [Formula: see text] credible regions can be as large as thousands of square degrees when only two sensitive detectors are operational. Determining the sky position of a significant fraction of detected signals to areas of 5-[Formula: see text] requires at least three detectors of sensitivity within a factor of [Formula: see text] of each other and with a broad frequency bandwidth. When all detectors, including KAGRA and the third LIGO detector in India, reach design sensitivity, a significant fraction of gravitational-wave signals will be localized to a few square degrees by gravitational-wave observations alone.
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Biofumigation is an integrated pest-management method involving the mulching of a glucosinolate-containing cover crop into a field in order to generate toxic isothiocyanates (ITCs), which are effective soil-borne-pest-control compounds. Variation in biofumigation efficacy demonstrates a need to better understand the factors affecting pest-control outcomes and develop best practices for choosing biofumigants, growth conditions, and mulching methods that allow the greatest potential isothiocyanate release. We measured the glucosinolate concentrations of six different commercial varieties of three biofumigant plant species: Brassica juncea (ISCI99, Vitasso, and Scala) Raphanus sativus (Diablo and Bento), and Sinapis alba (Ida Gold). The plants were grown in the range of commercially appropriate seeding rates and sampled at three growth stages (early development, mature, and 50% flowering). Within biofumigant species, the highest ITC-release potentials were achieved with B. juncea cv. ISCI99 and R. sativus cv. Bento. The highest ITC-release potential occurred at the 50% flowering growth stage across the species. The seeding rate had a minor impact on the ITC-release potential of R. sativus but had no significant effects on the ITC-release potentials of the B. juncea or S. alba cultivars.
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Isotiocianatos/química , Mostardeira/química , Raphanus/química , Sinapis/química , Fumigação , Glucosinolatos/química , Mostardeira/crescimento & desenvolvimento , Controle de Pragas , Raphanus/crescimento & desenvolvimento , Sinapis/crescimento & desenvolvimentoRESUMO
Individuals with OCD often identify psychosocial stress as a factor that exacerbates their symptoms, and many trace the onset of symptoms to a stressful period of life or a discrete traumatic incident. However, the pathophysiological relationship between stress and OCD remains poorly characterized: it is unclear whether trauma or stress is an independent cause of OCD symptoms, a triggering factor that interacts with a preexisting diathesis, or simply a nonspecific factor that can exacerbate OCD along with other aspects of psychiatric symptomatology. Nonetheless, preclinical research has demonstrated that stress has conspicuous effects on corticostriatal and limbic circuitry. Specifically, stress can lead to neuronal atrophy in frontal cortices (particularly the medial prefrontal cortex), the dorsomedial striatum (caudate), and the hippocampus. Stress can also result in neuronal hypertrophy in the dorsolateral striatum (putamen) and amygdala. These neurobiological effects mirror reported neural abnormalities in OCD and may contribute to an imbalance between goal-directed and habitual behavior, an imbalance that is implicated in the pathogenesis and expression of OCD symptomatology. The modulation of corticostriatal and limbic circuits by stress and the resultant imbalance between habit and goal-directed learning and behavior offers a framework for investigating how stress may exacerbate or trigger OCD symptomatology.