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Arthraxon hispidus is an introduced, rapidly spreading, and newly invasive grass in the eastern United States, yet little is known about the foundational biology of this aggressive invader. Germination responses to environmental factors including salinity, pH, osmotic potential, temperature, and burial depth were investigated to better understand its germination niche. Seeds from six populations in the Mid-Atlantic US germinated 95% with an average mean time to germination of 3.42 days of imbibition in the dark at 23°C. Germination occurred across a temperature range of 8-37°C and a pH range of 5-10 (≥83%), suggesting that neither pH nor temperature will limit germination in many environments. Arthraxon hispidus germination occurred in high salinity (342 mM NaCl) and osmotic potentials as low as -0.83MPa. The NaCl concentration required to reduce germination by 50% exceeded salinity concentrations found in soil and some brackish water saltmarsh systems. While drought adversely affects A. hispidus, 50% germination occurred at osmotic potentials ranging from -0.25 to -0.67 MPa. Given the climatic conditions of North America, drought stress is unlikely to restrict germination in large regions. Finally, emergence greatly decreased with burial depth. Emergence was reduced to 45% at 1-2 cm burial depths, and 0% at 8 cm. Emergence depths in concert with adequate moisture, germination across a range of temperatures, and rapid germination suggests A. hispidus' seed bank may be short-lived in moist environments, but further investigation is warranted. Given the broad abiotic tolerances of A. hispidus and a widespread native range, A. hispidus has the potential to germinate in novel territories beyond its currently observed invaded range.
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Germinação , Espécies Introduzidas , Temperatura , Germinação/fisiologia , Poaceae/fisiologia , Poaceae/crescimento & desenvolvimento , Salinidade , Concentração de Íons de Hidrogênio , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , SecasRESUMO
INTRODUCTION: Multiplanar mesh plating of patella fractures has become more popular in recent years. It was the goal of this study to compare the biomechanical stability of cannulated screw with anterior tension band to multiplanar mesh plating for fixation of transverse patella fractures in cadaver specimens. MATERIALS AND METHODS: Eight matched pairs of fresh frozen cadaveric knees were obtained and soft tissues dissected leaving the extensor mechanism, joint capsule, and retinaculum intact. Transverse fractures were created at the mid-portion of the patella. For each pair, one specimen was repaired using cannulated screws with anterior tension band, and the second was repaired using multiplanar mesh plating. Each specimen underwent cyclic extension loading with loads increasing by 1.1 kg after every 50 cycles. Interfragmentary displacement was measured at the end of each interval at both 5° and 45° of knee flexion angle, with fixation failure defined by >2 mm displacement. RESULTS: The specimens fixed with multiplanar mesh plating survived more cycles and higher loads than the specimens fixed with cannulated screws with anterior tension band (p = 0.011 comparing survival plots). After 150 cycles of extension loading, 3 of 8 of the specimens fixed with screws/tension band had failed, whereas none of the mesh plated specimens had failed. After 400 cycles, 7 of 8 of the screws/tension band had failed, whereas half of the mesh plated specimens had failed. CONCLUSIONS: While a more technically challenging and expensive technique, mesh plating for patella fractures appears to offer greater durability than traditional cannulated screw with tension banding.
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Placas Ósseas , Parafusos Ósseos , Cadáver , Fixação Interna de Fraturas , Fraturas Ósseas , Patela , Humanos , Patela/cirurgia , Patela/lesões , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Fenômenos Biomecânicos , Fraturas Ósseas/cirurgia , Fraturas Ósseas/fisiopatologia , Telas Cirúrgicas , Masculino , Feminino , Idoso , Teste de Materiais , Pessoa de Meia-Idade , Amplitude de Movimento ArticularRESUMO
A major challenge for tuberculosis (TB) drug development is to prioritize promising combination regimens from a large and growing number of possibilities. This includes demonstrating individual drug contributions to the activity of higher-order combinations. A BALB/c mouse TB infection model was used to evaluate the contributions of each drug and pairwise combination in the clinically relevant Nix-TB regimen [bedaquiline-pretomanid-linezolid (BPaL)] during the first 3 weeks of treatment at human equivalent doses. The rRNA synthesis (RS) ratio, an exploratory pharmacodynamic (PD) marker of ongoing Mycobacterium tuberculosis rRNA synthesis, together with solid culture CFU counts and liquid culture time to positivity (TTP) were used as PD markers of treatment response in lung tissue; and their time-course profiles were mathematically modeled using rate equations with pharmacologically interpretable parameters. Antimicrobial interactions were quantified using Bliss independence and Isserlis formulas. Subadditive (or antagonistic) and additive effects on bacillary load, assessed by CFU and TTP, were found for bedaquiline-pretomanid and linezolid-containing pairs, respectively. In contrast, subadditive and additive effects on rRNA synthesis were found for pretomanid-linezolid and bedaquiline-containing pairs, respectively. Additionally, accurate predictions of the response to BPaL for all three PD markers were made using only the single-drug and pairwise effects together with an assumption of negligible three-way drug interactions. The results represent an experimental and PD modeling approach aimed at reducing combinatorial complexity and improving the cost-effectiveness of in vivo systems for preclinical TB regimen development.
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Antituberculosos , Diarilquinolinas , Modelos Animais de Doenças , Linezolida , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis , Animais , Antituberculosos/farmacologia , Antituberculosos/farmacocinética , Antituberculosos/uso terapêutico , Linezolida/farmacologia , Linezolida/farmacocinética , Diarilquinolinas/farmacologia , Diarilquinolinas/farmacocinética , Camundongos , Mycobacterium tuberculosis/efeitos dos fármacos , Feminino , Nitroimidazóis/farmacologia , Nitroimidazóis/farmacocinética , Nitroimidazóis/uso terapêutico , Quimioterapia Combinada , Pulmão/microbiologia , Pulmão/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Testes de Sensibilidade Microbiana , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologiaRESUMO
OBJECTIVES: Standardized ('plain') packaging is effective in reducing the appeal of cigarettes among young people. This study examined the impact of plain packaging and brand imagery on interest in trying e-cigarettes among youth. STUDY DESIGN: Experimental design. METHODS: Two online experiments were conducted in February 2020 as part of the ITC Youth Tobacco & Vaping Survey, conducted with 13,624 16- to 19-year-olds in Canada, England, and the USA. In the between-group Experiment 1, participants were randomized to view a set of 3 e-cigarette brands, in either their original external packaging ('branded' condition) or standardized olive-green packaging ('standardized' condition), and asked to select the product they would be most interested in trying. The within-group Experiment 2 examined brand imagery directly on devices, including potential differences in appeal among subgroups. Each participant viewed 4 pod-style e-cigarette devices: one 'plain' and 3 in colourful 'skins'. Logistic regression models were conducted to test the effect of condition, adjusting for demographics, smoking and vaping status. RESULTS: In Experiment 1, participants in the 'standardized' packaging condition were significantly more likely to indicate 'I have no interest in trying any of these products' (72.3%) than those in the 'branded' condition (66.9%, AOR 1.45, 95% CI 1.33-1.59). Experiment 2 results indicated differences in e-cigarette appeal by sex in the selection of male- and female-oriented designs, and by cannabis use for a Rastafarian-themed design. CONCLUSIONS: Brand imagery on e-cigarettes can target products to specific subgroups. Removal of imagery, in the form of standardized packaging, has the potential to reduce interest in trying e-cigarettes among young people.
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Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Vaping , Humanos , Masculino , Feminino , Adolescente , Embalagem de Produtos/métodos , FumarRESUMO
During medical school, residency, or fellowship, many trainees struggle to balance their careers with starting a family. Some may feel the optimal time for parenthood is after completion of training, but the effect of increasing age on fertility is a real consideration for female physicians.1 Several studies have explored the impact of pregnancy and parental leave during surgical residency, yet little has been published on these topics during psychiatry training. This is surprising as psychiatry residents often address the challenges of integrating work and parenthood with their patients, yet it has not traditionally been within the culture of medicine to openly discuss this with colleagues. It is critical to address pregnancy and parenthood routinely during training and in the literature to reiterate the importance of work-life integration. In this article, we discuss current practices for psychiatry residents and advocate for the development of a standardized policy across psychiatry training programs that considers multiple aspects of childbearing including maternal mental health, family leave, and infertility.
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BACKGROUND: Dynamic compression plating is a fundamental type of bone fracture fixation used to generate interfragmentary compression. The goal of this study was to investigate the mechanics of the surgical application of these plates, specifically how plate prebend, screw location, fracture gap, and applied torque influence the resulting compressive pressures. METHODS: Synthetic bones with transverse fractures were fixed with locking compression plates. One side of the fracture was fixed with locking screws. On the other side of the fracture, a nonlocking screw was inserted eccentrically to induce interfragmentary compression. A pressure mapping sensor within the fracture gap was used to record the resulting pressure distribution. Plate prebends of 0 mm, 1.5 mm, and 3 mm were tested. Three locations of the eccentric screw, four levels of screw torque, and two initial fracture gap conditions also were tested. FINDINGS: With increasing plate prebend, fracture compression pressures shifted significantly toward the far cortex; however, compression force decreased (P < 0.05). The 1.5 mm prebend plate resulted in the greatest contact area. Increasing screw torque generally resulted in greater fracture compression force. The introduction of a 1 mm fracture gap at the far cortex prior to dynamic compression resulted in little or no fracture compression. INTERPRETATION: The model showed that increasing plate prebend results in an increasing shift of fracture compression pressures toward the far cortex; however, this is accompanied by decreases in compressive force. Initial fracture gaps at the far cortex can result in little or no compression.
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Fraturas Ósseas , Humanos , Fraturas Ósseas/cirurgia , Fixação Interna de Fraturas/métodos , Placas Ósseas , Parafusos Ósseos , Osso e Ossos , Fenômenos BiomecânicosRESUMO
OBJECTIVE: To determine whether intrawound vancomycin changes the bacteriology of surgical site infection pathogens and investigate the emergence of antibiotic-resistant pathogens. DESIGN: Secondary analysis of phase III, prospective, randomized clinical trial. SETTING: Thirty-six US trauma centers. PATIENT SELECTION CRITERIA: Patients who became infected after fixation of tibial plateau or pilon fracture. OUTCOME MEASURES AND COMPARISONS: Pathogen types and bacterial susceptibilities as determined from routine clinical culture in the operating room. RESULTS: Seventy-four patients were studied who were 67.5% male with a mean age of 48.6 years. A lower proportion of gram-positive cocci was observed in the vancomycin powder compared with the standard-of-care group (3.7% vs. 8.0%, P = 0.01). Methicillin-resistant Staphylococcus aureus infection incidence was comparable in both the vancomycin powder and the standard-of-care groups, but rates of methicillin-susceptible S. aureus infections were lower in the treatment group (1.4% vs. 4.8%, P = 0.01). The incidence of coagulase-negative Staphylococci and gram-negative rod infections were similar in both groups. There was no significant difference in susceptibilities between groups in rates of vancomycin-resistant enterococcus. CONCLUSIONS: Topical vancomycin powder decreases the likelihood of gram-positive infections consistent with the biologic activity of vancomycin. Fewer methicillin-susceptible S. aureus and coagulase-negative Staphylococci infections were observed in the group treated with vancomycin powder. An effect of vancomycin powder on methicillin-resistant S. aureus infection risk was not detected given the low incidence in both the intrawound vancomycin and the standard-of-care groups. There was no emergence of gram-negative rod infections or increased resistance patterns observed. Use of topical vancomycin powder does not seem to produce infections in these patients with greater antibiotic resistance than would have occurred without its use. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.
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Bacteriologia , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antibacterianos , Coagulase/farmacologia , Coagulase/uso terapêutico , Meticilina/farmacologia , Meticilina/uso terapêutico , Pós/farmacologia , Estudos Prospectivos , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle , VancomicinaRESUMO
It is unclear if cardiopulmonary resuscitation is an aerosol-generating procedure and whether this poses a risk of airborne disease transmission to healthcare workers and bystanders. Use of airborne transmission precautions during cardiopulmonary resuscitation may confer rescuer protection but risks patient harm due to delays in commencing treatment. To quantify the risk of respiratory aerosol generation during cardiopulmonary resuscitation in humans, we conducted an aerosol monitoring study during out-of-hospital cardiac arrests. Exhaled aerosol was recorded using an optical particle sizer spectrometer connected to the breathing system. Aerosol produced during resuscitation was compared with that produced by control participants under general anaesthesia ventilated with an equivalent respiratory pattern to cardiopulmonary resuscitation. A porcine cardiac arrest model was used to determine the independent contributions of ventilatory breaths, chest compressions and external cardiac defibrillation to aerosol generation. Time-series analysis of participants with cardiac arrest (n = 18) demonstrated a repeating waveform of respiratory aerosol that mapped to specific components of resuscitation. Very high peak aerosol concentrations were generated during ventilation of participants with cardiac arrest with median (IQR [range]) 17,926 (5546-59,209 [1523-242,648]) particles.l-1 , which were 24-fold greater than in control participants under general anaesthesia (744 (309-2106 [23-9099]) particles.l-1 , p < 0.001, n = 16). A substantial rise in aerosol also occurred with cardiac defibrillation and chest compressions. In a complimentary porcine model of cardiac arrest, aerosol recordings showed a strikingly similar profile to the human data. Time-averaged aerosol concentrations during ventilation were approximately 270-fold higher than before cardiac arrest (19,410 (2307-41,017 [104-136,025]) vs. 72 (41-136 [23-268]) particles.l-1 , p = 0.008). The porcine model also confirmed that both defibrillation and chest compressions generate high concentrations of aerosol independent of, but synergistic with, ventilation. In conclusion, multiple components of cardiopulmonary resuscitation generate high concentrations of respiratory aerosol. We recommend that airborne transmission precautions are warranted in the setting of high-risk pathogens, until the airway is secured with an airway device and breathing system with a filter.
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Reanimação Cardiopulmonar , Parada Cardíaca Extra-Hospitalar , Humanos , Animais , Suínos , Reanimação Cardiopulmonar/métodos , Parada Cardíaca Extra-Hospitalar/terapia , Coração , Respiração , ExpiraçãoRESUMO
OBJECTIVES: To estimate the generalizability of treatment effects observed in the VANCO trial to a broader population of patients with tibial plateau or pilon fractures. METHODS: Design and Setting: Clinical trial data from 36 United States trauma centers and Trauma Quality Programs registry data from more than 875 Level I-III trauma centers in the United States and Canada.Patient Selection Criteria: Patients enrolled in the VANCO trial treated with intrawound vancomycin powder from January 2015 to June 2017 and 31,924 VANCO-eligible TQP patients admitted in 2019 with tibial plateau and pilon fractures.Outcome Measure and Comparisons: Deep surgical site infection and gram-positive deep surgical site infection estimated in the TQP sample weighed by the inverse probability of trial participation. RESULTS: The 980 patients in the VANCO trial were highly representative of 31,924 TQP VANCO-eligible patients (Tipton generalizability index 0.96). It was estimated that intrawound vancomycin powder reduced the odds of deep surgical infection by odds ratio (OR) = 0.46 (95% confidence interval [CI] 0.25-0.86) and gram-positive deep surgical infection by OR = 0.39 (95% CI, 0.18-0.84) within the TQP sample of VANCO-eligible patients. For reference, the trial average treatment effects for deep surgical infection and gram-positive deep surgical infection were OR = 0.60 (95% CI, 0.37-0.98) and OR = 0.44 (95% CI, 0.23-0.80), respectively. CONCLUSIONS: This generalizability analysis found that the inferences of the VANCO trial generalize and might even underestimate the effects of intrawound vancomycin powder when observed in a wider population of patients with tibial plateau and pilon fractures. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
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Fraturas da Tíbia , Vancomicina , Humanos , Vancomicina/uso terapêutico , Vancomicina/farmacologia , Antibacterianos/uso terapêutico , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/tratamento farmacológico , Pós , Fraturas da Tíbia/cirurgia , América do Norte , Estudos RetrospectivosRESUMO
Problems associated with muddy pens have been identified as some of the most serious animal welfare issues related to outdoor feedlot beef production, but there is relatively little work examining the use of woodchip bedding for lot-fed beef cattle under conditions of cold, wet, but non-freezing winters on soil under-bases. This study examined the effects of graded levels of woodchip on the performance and behaviour of feedlot cattle housed in wet pen conditions. Bos taurus steers (n = 300; 379.1 ± 24.1 kg) were blocked by weight and breed and randomly assigned to 30 10-steer feedlot pens provided with either no woodchip bedding (Control, n = 10) manure interface only, or 15 cm depth of woodchip bedding (W15, n = 10) or 30 cm depth of woodchip bedding (W30, n = 10). The steers were housed in these treatment pens for 109 days on a feedlot ration, and the pens were irrigated so that approximately 74 mm of total precipitation (irrigation + natural rainfall) fell onto the pen surface every 30 days. Temperatures were mostly <20 °C maximum and -1 to 5 °C minimum. Steers were weighed on five occasions. Animal position and posture in pen were recorded once a week over an 8-hour day-time period. Carcase characteristics were measured, and adrenal gland weights were recorded. Providing woodchip bedding increased liveweight gain (P < 0.001) and gain:feed (G:F, P = 0.012) after day 28, increased DM intake (DMI) after day 92 (P = 0.049), and increased carcase weight (P = 0.001) and dressing percentage (P = 0.023). There was no additional benefit of W30 over W15 for liveweight gain or DMI, but the benefit of W15 for G:F was lower than that of W30 by the end of the feeding period (P = 0.012). There were no effects of bedding on other carcase quality traits. Steers in Control pens utilised the front of the pen for lying and standing more than the W15 and W30 steers (P < 0.001) suggesting the steers in the Control pens perceived the front of the pen as less aversive, potentially due to increased drainage compared to rest of the pen and proximity to feed bunk. Adrenal gland weight/kg and carcase weight tended to be higher in the Control treatment group than the W30 steers (P = 0.077). This research has demonstrated that for a 109-day feeding period in cold, wet conditions, steer performance and welfare can be improved by providing a minimum of 15 cm woodchip bedding.
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Esterco , Aumento de Peso , Bovinos , Animais , Temperatura , Estações do Ano , Glândulas Suprarrenais , Ração Animal/análise , Dieta/veterináriaRESUMO
A major challenge for tuberculosis (TB) drug development is to prioritize promising combination regimens from a large and growing number of possibilities. This includes demonstrating individual drug contributions to the activity of higher-order combinations. A BALB/c mouse TB infection model was used to evaluate the contributions of each drug and pairwise combination in the clinically relevant Nix-TB regimen (bedaquiline-pretomanid-linezolid [BPaL]) during the first three weeks of treatment at human equivalent doses. RS ratio, an exploratory pharmacodynamic (PD) marker of ongoing Mycobacterium tuberculosis rRNA synthesis, to-gether with solid culture CFU and liquid culture time to positivity (TTP) were used as PD markers of treatment response in lung tissue; and their time course profiles were mathematically modeled using rate equations with pharmacologically interpretable parameters. Antimicrobial interactions were quantified using Bliss independence and Isserlis formulas. Subadditive (or antagonistic) and additive effects on bacillary load, assessed by CFU and TTP, were found for bedaquiline-pretomanid and linezolid-containing pairs, respectively. In contrast, subadditive and additive effects on rRNA synthesis were found for pretomanid-linezolid and bedaquiline-containing pairs, respectively. Additionally, accurate predictions of the response to BPaL for all three PD markers were made using only the single-drug and pairwise effects together with an assumption of negligible three-way drug interactions. The results represent an experimental and PD modeling approach aimed at reducing combinatorial complexity and improving the cost-effectiveness of in vivo systems for preclinical TB regimen development.
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Substituting the sole primary hydroxyl group of the low molecular weight organogelator (LMOG), 1,3:2,4-dibenzylidene-D-sorbitol (DBS), with a halogen atom (Cl, Br, or I; i.e., 6-Cl-DBS, 6-Br-DBS, or 6-I-DBS) drastically alters the supramolecular self-assembled fibrillar network (SAFiN) that forms when the molecules aggregate. The SAFiN varies depending on the solvent properties, impacting the role of non-covalent hydrogen- and halogen-bonding interactions along and between fibers. The halogenated DBS derivatives have more coherent crystalline fibers than DBS, with larger length-to-width aspect ratios. High-resolution synchrotron powder X-ray diffraction of each wet-state gel in toluene and DFT optimization obtained complete structures for the three halogenated DBS derivatives in their SAFiNs. The presence of a halogen atom reduces the reliance on hydrogen bonding by enabling new halogen bonding interactions that impact the self-assembly behavior, especially in solvents of higher polarity. For 6-I-DBS and 6-Br-DBS, the primary forces driving molecular self-assembly are C-Hâ¯π and intermolecular halogen-to-halogen interactions, and there is one unique molecule in each unit cell. However, the Cl atoms of 6-Cl-DBS are not close, and its SAFiN structures rely more on hydrogen bonding. As a result, the enhanced hydrogen bonding, electronic differences among the halogens, and spatial factors allow its unit cell to include two independent molecules of 6-Cl-DBS.
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Recent research on item-method directed forgetting demonstrates that forget instructions not only decrease recognition for targets, but also decrease false recognition for foils from the same semantic categories as targets instructed to be forgotten. According to the selective rehearsal account of directed forgetting, this finding suggests that remember instructions may engage elaborative rehearsal of the category-level information of items. In contrast to this explanation, Reid and Jamieson (Canadian Journal of Experimental Psychology / Revue canadienne de psychologie expérimentale, 76(2), 75-86, 2022) proposed that the differential rates of false recognition may emerge at retrieval when foils from "remember" and "forget" categories are compared to traces in memory. Using MINERVA S, an instance model of memory based on MINERVA 2 that incorporates structured semantic representations, Reid and Jamieson successfully simulated lower false recognition for foils from "forget" categories without assuming rehearsal of category-level information. In this study, we extend the directed forgetting paradigm to categories consisting of orthographically related nonwords. Presumably participants would have difficulty rehearsing category-level information for these items because they would have no pre-experimental knowledge of these categories. To simulate the findings in MINERVA S, we imported structured orthographic representations rather than semantic representations. The model not only predicted differential rates of false recognition for foils from "remember" and "forget" categories, but also predicted higher rates of false recognition overall than what was observed for semantic categories. The empirical data closely matched these predictions. These data suggest that differential rates of false recognition due to remember and forget instructions emerge at retrieval when participants compare recognition probes to traces stored in memory.
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Sinais (Psicologia) , Reconhecimento Psicológico , Humanos , Canadá , Rememoração Mental , AprendizagemRESUMO
Aerosol-generating procedures are medical interventions considered high risk for transmission of airborne pathogens. Tracheal intubation of anaesthetised patients is not high risk for aerosol generation; however, patients often perform respiratory manoeuvres during awake tracheal intubation which may generate aerosol. To assess the risk, we undertook aerosol monitoring during a series of awake tracheal intubations and nasendoscopies in healthy participants. Sampling was undertaken within an ultraclean operating theatre. Procedures were performed and received by 12 anaesthetic trainees. The upper airway was topically anaesthetised with lidocaine and participants were not sedated. An optical particle sizer continuously sampled aerosol. Passage of the bronchoscope through the vocal cords generated similar peak median (IQR [range]) aerosol concentrations to coughing, 1020 (645-1245 [120-48,948]) vs. 1460 (390-2506 [40-12,280]) particles.l-1 respectively, p = 0.266. Coughs evoked when lidocaine was sprayed on the vocal cords generated 91,700 (41,907-166,774 [390-557,817]) particles.l-1 which was significantly greater than volitional coughs (p < 0.001). For 38 nasendoscopies in 12 participants, the aerosol concentrations were relatively low, 180 (120-525 [0-9552]) particles.l-1 , however, five nasendoscopies generated peak aerosol concentrations greater than a volitional cough. Awake tracheal intubation and nasendoscopy can generate high concentrations of respiratory aerosol. Specific risks are associated with lidocaine spray of the larynx, instrumentation of the vocal cords, procedural coughing and deep breaths. Given the proximity of practitioners to patient-generated aerosol, airborne infection control precautions are appropriate when undertaking awake upper airway endoscopy (including awake tracheal intubation, nasendoscopy and bronchoscopy) if respirable pathogens cannot be confidently excluded.
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Tosse , Vigília , Humanos , Tosse/etiologia , Aerossóis e Gotículas Respiratórios , Intubação Intratraqueal/métodos , LidocaínaRESUMO
Abnormal reward processing is an important yet understudied risk factor for suicide. Recent neuroimaging studies have found that suicidality is associated with abnormal reward-related neural reactivity and connectivity across a wide range of brain regions and circuits. The varying, and oftentimes discrepant, findings have hindered progress in elucidating the neurobiological link between reward processing dysfunction and suicide risk. Some of this variability is likely related to different reward-related paradigms that are utilized across studies. The primary aim of the current study was to address these issues by comparing neural reactivity between youth with and without a history of suicidal ideation during direct manipulation of reward parameters. A total of 108 unmedicated youth, ages 17-19, were classified into two groups: 1) history of suicidal ideation (n = 39) and 2) no history of suicidal ideation (n = 69). All participants completed a novel reward anticipation task probing anticipation of predictable (P-reward) and unpredictable (U-reward) monetary reward. Results revealed that compared with controls, youth with a history of suicidal ideation exhibited increased neural activation in the dorsal anterior cingulate cortex (dACC) and right anterior insula (aINS) during anticipation of U-reward. There were no group differences during anticipation of P-reward. These findings suggest that propensity for suicidal ideation may be related to specific abnormalities during anticipation of U-reward, but not P-reward.
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Imageamento por Ressonância Magnética , Suicídio , Humanos , Adolescente , Adulto Jovem , Adulto , Imageamento por Ressonância Magnética/métodos , Ideação Suicida , Encéfalo/diagnóstico por imagem , Recompensa , Antecipação PsicológicaRESUMO
Reversing large-scale habitat degradation and deforestation goes beyond what can be achieved by site-level ecological restoration and a landscape ecology perspective is fundamental. Here we assess the relative importance of tree cover and its configuration on forest-dependent birds and late-successional tree seedlings in restoration sites in southern Costa Rica. The abundance and species richness of birds increased in landscapes with more corridors, higher tree cover, and lower levels of fragmentation, highlighting the importance of riparian corridors for connectivity, and continuous tree cover as suitable habitat. Landscape variables affected abundance and species richness of seedlings similarly, but effects were weaker, possibly because seedlings face establishment limitation in addition to dispersal limitation. Moreover, the scale of landscape effects on seedlings was small, likely because proximal individual trees can significantly influence recruitment in restoration plots. Results underscore the importance of incorporating landscape-level metrics to restoration projects, as knowing the extent, and how the landscape may affect restoration outcomes can help to infer what kind of species will arrive to restoration plots.
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Florestas , Clima Tropical , Animais , Aves , Conservação dos Recursos Naturais , Ecossistema , Plântula , ÁrvoresRESUMO
Previous research has found that reading a list of ostensibly unrelated expressions based on the same underlying conceptual metaphor can evoke false recognition on a memory task for new expressions that use the same metaphor, the so-called conceptual metaphor false memory effect. We examined the automaticity of this effect by dividing participants' attention with a concurrent task. In Study 1, attention was manipulated while participants read the lists of expressions, whereas in Study 2, attention was manipulated both when they read the lists and when they were engaged in the later recognition memory test. Across both studies, the conceptual metaphor false memory effect was observed when conscious processing was limited by dividing attention. These data support the argument that conceptual metaphors are automatically activated when metaphorical expressions are read.
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Atenção , Metáfora , Atenção/fisiologia , Humanos , MemóriaRESUMO
New approaches for the sensitive and accurate quantification of aerosol optical properties are needed to improve the current understanding of the unique physical chemistry of airborne particles and to explore their roles in fields as diverse as chemical manufacturing, healthcare, and atmospheric science. We have pioneered the use of cavity ring-down spectroscopy (CRDS), with concurrent angularly resolved elastic light scattering measurements, to interrogate the optical properties of single aerosol particles levitated in optical and electrodynamic traps. This approach enables the robust quantification of optical properties such as extinction cross sections for individual particles of known size. Our measurements can now distinguish the scattering and absorption contributions to the overall light extinction, from which the real and imaginary components of the complex refractive indices can be retrieved and linked to chemical composition. In this Feature Article, we show that this innovative measurement platform enables accurate and precise optical measurements for spherical and nonspherical particles, whether nonabsorbing or absorbing at the CRDS probe wavelength. We discuss the current limitations of our approach and the key challenges in physical and atmospheric chemistry that can now be addressed by CRDS measurements for single aerosol particles levitated in controlled environments.
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Montagliani and Hockley (2019) presented evidence that item-method directed forgetting not only leads to worse recognition of forget-cued targets than remember-cued targets but also better rejection of foils associated with forget-cued targets than remember-cued targets. Based on that result, they proposed that participants elaboratively encode more category-level information about R-cued targets. We present a retrieval-based explanation of the result within an instance-based memory model. The model imports word representations from two distributional semantic models, latent semantic analysis (LSA) and random permutation model (RPM), into an instance-based model of memory, MINERVA 2. The model reproduced Montagliani and Hockley's results without requiring assumptions about elaborated encoding of category-level information at study. The simulations demonstrate that whereas Montagliani and Hockley's findings are consistent with an account grounded in elaborated encoding of words at study, the results do not force that conclusion. Instead, better encoding of remember-cued targets at study establishes the conditions for retrieval-time effects at test to produce a corresponding influence on false recognition for category-related foils. Our model can be used as a formal tool to think about and study the incidental consequences of item directed forgetting in recognition memory. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
Assuntos
Rememoração Mental , Reconhecimento Psicológico , Simulação por Computador , Sinais (Psicologia) , Humanos , SemânticaRESUMO
BACKGROUND: Open respiratory suctioning is defined as an aerosol generating procedure (AGP). Laryngopharyngeal suctioning, used to clear secretions during anaesthesia, is widely managed as an AGP. However, it is uncertain whether upper airway suctioning should be designated as an AGP due to the lack of both aerosol and epidemiological evidence. AIM: To assess the relative risk of aerosol generation by upper airway suctioning during tracheal intubation and extubation in anaesthetized patients. METHODS: This prospective environmental monitoring study was undertaken in an ultraclean operating theatre setting to assay aerosol concentrations during intubation and extubation sequences, including upper airway suctioning, for patients undergoing surgery (N=19). An optical particle sizer (particle size 0.3-10 µm) sampled aerosol 20 cm above the patient's mouth. Baseline recordings (background, tidal breathing and volitional coughs) were followed by intravenous induction of anaesthesia with neuromuscular blockade. Four periods of laryngopharyngeal suctioning were performed with a Yankauer sucker: pre-laryngoscopy, post-intubation, pre-extubation and post-extubation. FINDINGS: Aerosol was reliably detected {median 65 [interquartile range (IQR) 39-259] particles/L} above background [median 4.8 (IQR 1-7) particles/L, P<0.0001] when sampling in close proximity to the patient's mouth during tidal breathing. Upper airway suctioning was associated with a much lower average aerosol concentration than breathing [median 6.0 (IQR 0-12) particles/L, P=0.0007], and was indistinguishable from background (P>0.99). Peak aerosol concentrations recorded during suctioning [median 45 (IQR 30-75) particles/L] were much lower than during volitional coughs [median 1520 (IQR 600-4363) particles/L, P<0.0001] and tidal breathing [median 540 (IQR 300-1826) particles/L, P<0.0001]. CONCLUSION: Upper airway suctioning during airway management was not associated with a higher aerosol concentration compared with background, and was associated with a much lower aerosol concentration compared with breathing and coughing. Upper airway suctioning should not be designated as a high-risk AGP.