Winner Winner Turkey Dinner! An Empirical Approach to Measuring Palatability and Satisfaction with Emergency Department Turkey Sandwiches.

Introduction: Despite their popularity in many EDs, little is known regarding perceptions of turkey sandwiches among patients. Given the importance of turkey sandwiches as a form of nutrition provided in EDs, we sought to quantify the composition and taste of ED turkey sandwiches through a quantitative assessment of turkey sandwiches by ED staff. Methods: This was a blinded observational study performed at a tertiary, urban academic medical center in Boston, MA. We collected ED turkey sandwiches up to 48 hours prior to study days from 4 emergency departments in the Boston area (2 community hospitals and 2 academic medical centers). We enrolled ED physicians, nurses, physician assistants, and staff who were exposed to four sandwiches in a random fashion. Participants were asked to assess sandwiches on a Likert scale of 1 to 5 on a variety of factors including, nutritional value "goodness", smell "olfactory", texture "bite", ingredient distribution "balance", appearance "look", and flavor "edibility" to produce a composite score for sandwich quality (GOBBLE score). Next, participants were asked standardized questions surrounding suitability for consumption and nutrition on a 10 point Likert scale. We calculated mean scores and measured differences using t-tests. Results: We enrolled 22 participants over the study period. Twenty-one participants completed all measures. GOBBLE scores were calculated and averaged for sandwiches. A One-way ANOVA test was performed to measure statistically significant differences between mean GOBBLE scores (p<0.05) with a post hoc Tukey HSD procedure used to assess for statistically significant difference for pairwise comparison. A significant difference (p=0.009) was noted between the 4 sandwiches being compared, with a single site outperforming the others. Aggregating for academic and community sites demonstrated no statistically significant difference (p=0.08). Sandwiches in general were not considered healthy or palatable by study subjects. Conclusion: Despite out-performance by a single ED, there is no significant difference in the quality of sandwiches provided to patients in EDs between academic and community hospitals. ED turkey sandwiches do not appear to be food items that are viewed as healthy or recommended to patients by ED staff who participated in this study.

Wartime toxicology: the spectre of chemical and radiological warfare in Ukraine.

The unprovoked invasion of Ukraine by the Russian Federation has resulted in the largest humanitarian crisis in Europe since World War II. As fighting intensifies throughout Ukraine, there is an increasing concern that the Russian Federation may consider the direct use of chemical or radiological weapons against military personnel and civilians in Ukraine. Despite prohibition of chemical weapons from the Chemical Weapons Convention of 1997, recent evidence has demonstrated that state actors will continue to use these agents as weapons of war and terror, despite publicly denying their use. We review chemical weapons produced and used by the Russian Federation (or its allies) to identify plausible risks in the Russian war in Ukraine. We also provide rapid assessment and treatment guidelines to recognize and manage these acute exposures.

Severe colchicine poisoning treated successfully with kidney replacement therapy and plasmapheresis: a case report.

Colchicine is commonly prescribed for treatment of inflammatory conditions but has a narrow therapeutic window and dangerous toxicity profile. Here we describe a case of survival after massive unintentional colchicine overdose treated with plasmapheresis and renal replacement therapy. A 37 year old male with history of pericarditis presented to the Emergency Department with a chief complaint of nausea, vomiting, and diarrhea after unintentionally ingesting 36 mg of colchicine 17 h prior to arrival. An initial colchicine concentration resulted at 5.1 ng/mL (30 h post-ingestion) and peaked at 12 ng/mL (40 h post-ingestion). He was treated with continuous kidney replacement therapy (CKRT) beginning on his first day of hospitalization and with plasmapheresis on hospital days two through four. The patient's course was complicated by multiorgan failure including coagulopathy, respiratory failure, neuropathy, renal failure, pancytopenia, and heart failure. He was discharged to inpatient rehabilitation on hospital day 24. On clinical follow up four months after discharge the patient was found to have no significant persistent morbidity related to colchicine overdose.

Traumatic pedestrian and bicyclist injuries associated with intoxication.

BACKGROUND: Drug and alcohol use are risk factors for trauma among operators of motor vehicles and contribute to trauma in pedestrians and bicyclists. We describe the prevalence of drug and alcohol use and clinical consequences in a cohort of pedestrians and bicyclists with trauma. METHODS: We analyzed a 25-month data set of 916 trauma team activations from January 2017-January 2019 at an urban, level I trauma center. Blood ethanol levels and urine toxicology screens were obtained in 94 pedestrian and bicyclist trauma activations. We compared pedestrians or bicyclists with a positive urine or blood screen (n = 69) to those with negative screens (n = 25). We conducted a retrospective chart review to determine mechanism of injury, injury pattern, and disposition from the emergency department (ED). RESULTS: Overall, 38 (55%) of injured patients with positive screen were pedestrians and 31 (45%) were bicyclists. Fentanyl was the most commonly detected drug (n = 38; 40%), followed by opiates (n = 27; 29%), and tetrahydrocannabiol (THC) (n = 23; 25%). Twenty-one patients were positive for ethanol. Pedestrians and bicyclists with positive toxicology screens were significantly more likely to sustain fractures (p < .01), require an operative procedure (p < .05), or intensive care unit admission (p < .05). CONCLUSION: Our study builds on previous literature which suggests that intoxicated bicyclists and pedestrians suffer frequent and more severe injury than their sober counterparts. Public health campaigns should educate bicyclists and pedestrians about the risks of cycling or walking in areas of road traffic while under the influence of alcohol or illicit drugs.

Intentional Hydroxychloroquine Overdose Treated with High-Dose Diazepam: an Increasing Concern in the COVID-19 Pandemic.

INTRODUCTION: Recent attention on the possible use of hydroxychloroquine and chloroquine to treat COVID-19 disease has potentially triggered a number of overdoses from hydroxychloroquine. Toxicity from hydroxychloroquine manifests with cardiac conduction abnormalities, seizure activity, and muscle weakness. Recognizing this toxidrome and unique management of this toxicity is important in the COVID-19 pandemic. CASE REPORT: A 27-year-old man with a history of rheumatoid arthritis presented to the emergency department 7 hours after an intentional overdose of hydroxychloroquine. Initial presentation demonstrated proximal muscle weakness. The patient was found to have a QRS complex of 134 ms and QTc of 710 ms. He was treated with early orotracheal intubation and intravenous diazepam boluses. Due to difficulties formulating continuous diazepam infusions, we opted to utilize an intermitted intravenous bolus strategy that achieved similar effects that a continuous infusion would. The patient recovered without residual side effects. DISCUSSION: Hydroxychloroquine toxicity is rare but projected to increase in frequency given its selection as a potential modality to treat COVID-19 disease. It is important for clinicians to recognize the unique effects of hydroxychloroquine poisoning and initiate appropriate emergency maneuvers to improve the outcomes in these patients.

Chloroquine, hydroxychloroquine and COVID-19.

The media have featured the antimalarials chloroquine (CQ) and hydroxychloroquine (HCQ) to treat coronavirus (COVID-19). Political leaders have touted their use and recommended availability to the public. These anti-inflammatory agents have substantial human toxicity with a narrow therapeutic window. CQ and HCQ poisoning cause myocardial depression and profound hypotension due to vasodilation. Bradycardia and ventricular escape rhythms arise from impaired myocardial automaticity and conductivity due to sodium and potassium channel blockade. With cardiotoxicity, ECGs may show widened QRS, atrioventricular heart block and QT interval prolongation. CQ may also cause seizures, often refractory to standard treatment. Of concern is pediatric poisoning, where 1-2 pills of CQ or HCQ can cause serious and potentially fatal toxicity in a toddler. The treatment of CQ/HCQ poisoning includes high-dose intravenous diazepam postulated to have positive ionotropic and antidysrhythmic properties that may antagonize the cardiotoxic effects of CQ. Infusions of epinephrine titrated to treat unstable hypotension, as well as potassium for severe hypokalemia may be required. Current scientific evidence does not support treatment or prophylactic use of these agents for COVID-19 disease. Regulatory and public health authorities recognize that CQ/HCQ may offer little clinical benefit and only add risk requiring further investigation before wider public distribution.

Cocaine and its major metabolites in plasma and urine samples from patients in an urban emergency medicine setting.

In this retrospective study, we examined the levels of cocaine and its major metabolites in plasma and urine from 29 randomly selected emergency department patients (19 males and 10 females, aged 19 to 55) whose urine screened positive for benzoylecgonine using fluorescence polarization immunoassay. Levels of cocaine along with benzoylecgonine, ecgonine methyl ester, and norcocaine were quantitated in EDTA plasma and urine from each patient using gas chromatography-mass spectrometry with selected ion monitoring. Admission diagnosis and history were also obtained for each patient. In plasma, the levels were 16-130 ng/mL for cocaine (n = 3), 27-96 ng/mL for ecgonine methyl ester (n = 9), and 18-1390 ng/mL for benzoylecgonine (n = 22). Norcocaine was not detected in any of the plasma samples. In urine, the concentration ranges were 4-40,130 ng/mL for cocaine (n = 23), 36-660,500 ng/mL for ecgonine methyl ester (n = 27), and 9-2520 ng/mL for norcocaine (n = 9). All urine samples were positive for benzoylecgonine (106-3,361,000 ng/mL), and benzoylecgonine was the only metabolite present in two urine samples (at concentrations of 407 and 435 ng/mL). Two patients had plasma and urine samples positive for all analytes (except norcocaine in plasma). The patient with the highest urinary concentrations of cocaine (40,130 ng/mL), ecgonine methyl ester (660,500 ng/mL), benzoylecgonine (3,361,000 ng/mL), and norcocaine (2520 ng/mL) had a small quantity of benzoylecgonine (465 ng/mL) in plasma. No correlation was noted with patient history, admitting diagnosis or symptomatology, or plasma/urine levels of cocaine or any of its metabolites.

Simultaneous detection and quantitation of diethylene glycol, ethylene glycol, and the toxic alcohols in serum using capillary column gas chromatography.

Determination of toxic glycols and alcohols in an emergency setting requires a rapid yet accurate and reliable method. To simultaneously determine diethylene glycol (DEG) along with ethylene glycol, methanol, isopropanol, acetone, and ethanol, we modified a previously developed gas chromatographic (GC) method. The system used a Hewlett-Packard 6890 GC with EPC, a Gooseneck splitless liner, and an Rtx-200 capillary column (30 m x 0.53-mm i.d., 3 mm). After serum samples were deproteinized using ultrafiltration (Millipore Ultrafree-MC), 1 mL of the protein-free filtrate was manually injected into the GC. Internal standards for alcohols (and acetone) and glycols were n-propanol and 1,3-butanediol, respectively. All compounds eluted within 3.5 min (linear temperature gradient from 40 to 260 degrees C); total run time was 6.5 min. Limit of detection and linear range for all compounds were 1 or 2.5 mg/dL and 0-500 mg/dL, respectively. In addition, there was no interference from propionic acid, propylene glycol, and 2,3-butanediol. The modifications in the equipment and temperature program allowed increased resolution and thus, detection and reliable quantitation of DEG and other common toxic glycols and alcohols of clinical interest.

Training military medics as civilian prehospital care providers in Southern Sudan.

OBJECTIVE: To describe and evaluate a training program to teach civilian prehospital care to military medics in the Sudan People's Liberation Army (SPLA). METHODS: Forty-one SPLA military personnel with variable prior medical experience participated in the course. Pre- and postintervention tests were used to evaluate participant knowledge and skill level, and test results were compared using paired t-tests. RESULTS: An intensive 40-hour course consisting of didactic teaching sessions, small-group discussions, and practical skill stations was completed during November 1997. Thirty-seven participants successfully completed the program. Four medics with significant prior experience were trained as teaching assistants. The pretest scores for the other 33 participants ranged from 25.0% to 75.0% (SD 12.4). The posttest scores ranged from 25.0% to 87.5% (SD 15.2), with a mean improvement in test scores of 35.0% (p < 0.0005). The most striking improvements were noted in the knowledge of subjects related to wound care, hemorrhage, and head trauma. CONCLUSIONS: A field medic training program in Southern Sudan was conducted utilizing an interactive training curriculum. This program may serve as an educational model to teach prehospital care principles in other areas of international conflict.

Toxicological deaths of major league baseball players.

REPORT: A retrospective review of major league baseball records was conducted for players' cause of death. Any death attributed to a toxic exposure was analyzed for causal agent, reason for exposure, age at time of death, location, time of year, team, and dominant position played while active. RESULTS: Twenty-eight poisoning deaths were identified between 1889-1995. The most common agent was carbon monoxide (8), followed by methane gas asphyxiation (4), opiate overdose (4), ethanol (3), and phenol (3). Fourteen (50%) were unintentional deaths, 13 (46%) were suicidal in nature, and 1 (4%) homicidal. The majority of deaths (75%) occurred after the players had retired from the game. The leading position was pitcher (13), followed by catcher (5), outfield (4), second base (2), first (1), shortstop (1), third (1), and umpire (1). CONCLUSIONS: With society's increased illicit drug use, better drug detection, escalating salaries, and increased public pressures placed on present-day players, more poisonings may likely occur.

Assaults from penetrating trauma in the State of Illinois.

This study was undertaken to evaluate the incidence, epidemiology, and temporal relationships of assaults in the State of Illinois from penetrating trauma presenting to Level I and Level II trauma centers, and to project the impact of these variables on hospital staffing. A retrospective analysis was performed on 4 months of data (7/1/92 to 10/31/92) provided by the Illinois Department of Public Health describing consecutive assaults with firearms or knives presenting to all Level I and Level II trauma facilities in the State of Illinois. Data were analyzed for epidemiological parameters including age, gender, and race. Other variables analyzed included trauma score, Glasgow Coma Scale (GCS) score, ethanol levels, urine toxicology results, and mortality. The data were also analyzed for temporal patterns of hospital presentations with respect to the time of day and day of the week. A total of 1,288 cases of penetrating wounds were analyzed. Of these, 881 (68.4%) resulted from firearms and 407 (31.6%) resulted from stab wounds. Ages of all penetrating trauma victims ranged from less than 1 year to 84 years of age. The mean age for firearm victims was 25.0 +/- 10.8 (SD) years and 30.5 +/- 11.4 years for stabbing victims. Ninety percent of penetrating trauma victims were male and 10% were female. Seventy-two percent of the victims were African-American, 13% Hispanic, 13% Caucasian, and 2% other. Alcohol levels were available for 727 of the 1,288 (56.4%) patients. Of these 727, 433 (59.6%) had measurable levels. The results of drug screens were available for 582 of the 1,288 (45.1%) victims. Of these 582, 208 (35.7%) were positive. Other than alcohol, cocaine was the most frequently detected drug, accounting for 58.4% of the positive drug screens. Firearm victims had significantly lower trauma scores (10.5 v 11.2) and GCS scores (13.2 v 14.3) than stab victims. Significant circadian patterns of penetrating trauma were observed for both types of assaults. For assaults with firearms, the circadian rhythm peaked at 23.1 +/- 0.36 hours. For assaults with knives, the circadian rhythm peaked at 23.7 +/- 0.44 hours. Weekly patterns were not statistically significant for each individual type of assault. However, when the data were pooled, a weekly pattern peaking on Thursday was observed. These patterns of presentation for assaults are a significant finding that may have implications for hospital staff scheduling of trauma center physicians, nurses, technicians, security, social service, and other ancillary staff.

Analysis of cocaine chronotoxicology in an urban ED.

To describe the chronotoxicology of cocaine and its potential impact on emergency department (ED) staffing and services, Drug Abuse Warning Network (DAWN) data from a single urban university ED were retrospectively reviewed. The DAWN data reviewed spanned an 11-year period (1/1/83 through 12/31/93), and 3,762 patients were enrolled. Patients were included if the ED records included documentation of recent cocaine abuse prior to presentation to the ED. Of the 3,762 study patients, 1,609 (43%) had documentation of recent cocaine use: 506 (32%) had used cocaine alone, 614 (38%) had used cocaine and ethanol in combination, and 489 (30%) had used cocaine in combination with other drugs. For all patients using cocaine, there were two significant rhythms (P < .05) identified: a circadian rhythm that peaked at 1800 and a 12-hour rhythm that peaked at approximately noon and midnight. A significant rhythmicity was found among cocaine-using patients who presented during the study period. Increased or shift-adjusted staffing focusing specifically on psychosocial services, detoxification, and security during these peak hours may provide more efficient emergent care for this subpopulation of patients.

Prehospital severity scoring at major rock concert events.

INTRODUCTION: Rock and contemporary music concerts are popular, recurrent events requiring on-site medical staffing. STUDY OBJECTIVE: To describe a novel severity score used to stratify the level of acuity of patients presenting to first-aid stations at these events. METHODS: Retrospective review of charts generated at the first-aid stations of five major rock concerts within a 60,000 spectator capacity, outdoor, professional sports stadium. Participants included all concert patrons presenting to the stadium's first-aid stations as patients. Data were collected on patient demographics, history of drug or ethanol usage while at the concert event, first-aid station time, treatment rendered, diagnosis, and disposition. All patients evaluated were retrospectively assigned a "DRUG-ROCK" Injury Severity Score (DRISS) to stratify their level of acuity. Individual concert events and patient dispositions were compared statistically using chi-square, Fisher's exact, and the ANOVA Mean tests. RESULTS: Approximately 250,000 spectators attended the five concert events. First-aid stations evaluated 308 patients (utilization rate of 1.2 per 1,000 patrons). The most common diagnosis was minor trauma (130; 42%), followed in frequency by ethanol/illicit drug intoxication (98; 32%). The average time in the first-aid station was 23.5 +/- 22.5 minutes (+/- standard deviation; range: 5-150 minutes). Disposition of patients included 100 (32.5%) who were treated and released; 98 (32%) were transported by paramedics to emergency departments (EDs); and 110 (35.5%) signed-out against medical advise (AMA), refusing transport. The mean DRISS was 4.1 (+/- 2.65). Two-thirds (67%) of the study population were ranked as mild by DRISS criteria (score = 1-4), with 27% rated as moderate (score = 5-9), and 6% severe (score > 10). The average of severity scores was highest (6.5) for patients transported to hospitals, and statistically different from the scores of the average of the treated and released and AMA groups (p < 0.005). CONCLUSION: The DRISS was useful in stratifying the acuity level of this patient population. This severity score may serve as a potential triage mechanism for future mass gatherings such as rock concerts.

Health care in post-war Rwanda: re-establishing a national hospital using a mentor approach.

OBJECTIVES: To describe the rehabilitation of a large referral hospital amid the civil war in Rwanda, and to discuss the effectiveness of a mentor approach in re-establishing the facility's administrative structure. DESIGN: A mentor administrative design was used to re-establish the hospital personnel structure. This approach linked Rwandan health workers with foreign medical consultants. Formal interviews to evaluate the acceptance and effectiveness of the mentor administration model were conducted with foreign and Rwandan administrative staff. Six month retrospective review of hospital demographics (August 1994-January 1995) was compared to 1993 pre-war data (January-December, 1993). SETTING: The Central Hospital of Kigali, a 600 bed facility in Rwanda, East Africa. PARTICIPANTS: Rwandan and foreign administrators, non-government relief organizations (NGOs), United Nations Military forces, and patients presenting to the Central Hospital. RESULTS: The hospital became fully functional in August of 1994. Both foreign and Rwandan administrators surveyed stated that the mentor program was effective but the hospital would ultimately require external financial support for sustainability. A total of 38,042 patients were treated at the hospital during the six month study period. Compared to 1993 pre-war data, there was a substantial increase in both the overall patient volume and the number of traumatic injuries. Despite this, the case fatality ratio during the post-war period was significantly lower. CONCLUSIONS: A mentor approach was utilized to re-establish the administrative structure of the Central Hospital of Kigali. The facility was able to successfully function despite a larger patient volume compared to the pre-war period. This collaborative effort between NGOs and Rwandan personnel resulted in the development of a sustainable administrative and medical program. The use of a mentor administration may serve as a model for future rehabilitative efforts abroad.

Emergency medicine education intervention in Rwanda.

STUDY OBJECTIVE: To describe the effectiveness of an emergency medical education program in a postwar developing country. METHODS: A prospective, nonrandomized interrupted time-series study was conducted in an emergency department at a national referral hospital in Rwanda immediately after the 1994 civil war. Participants included 11 medical personnel staffing the ED comprising physicians, nurses, and medical assistants. International medical relief workers in the ED identified deficiencies by directly observing routine clinical practices. On the basis of this assessment, formal training programs in trauma resuscitation, airway management, wound care, and blood/fluid precautions were conducted. Subjects were then observed 1 week and 2 months after the educational programs and scored on a standardized data-collection form. Scores before and after intervention were compared with the use of Fisher's exact test to determine program effectiveness. RESULTS: Educational interventions with statistically significantly longer term effects included wound management principles and blood/fluid precautions (before versus after intervention, P < .05). Interventions with the least sustained effect included advanced airway interventions and procedures related to trauma resuscitation. CONCLUSION: Educational seminars proved to have the greatest sustained effect on those behaviors requiring minimal equipment and noncomplex medical decisionmaking.

Drug use patterns at major rock concert events.

STUDY OBJECTIVE: To describe alcohol and drug use patterns in patients presenting to first aid stations at major rock concerts. METHODS: We retrospectively reviewed all charts generated at the first aid stations of five major rock concerts featuring the rock groups Pink Floyd, the Grateful Dead, and the Rolling Stones. The first aid stations, located at a sports stadium, were staffed by paramedics, emergency medicine nurses, and physicians. We recorded the following data: patient demographics, history of drug or ethanol use, time spent by patient in first aid station, treatment rendered, diagnosis, and patient disposition. RESULTS: A total of 253, 286 spectators attended the five concert events. The rate of use of the first aid station was 1.2 per 1,000 patrons. The average age of the patrons was 26.3 +/- 7.9 years (range, 3 to 56 years). The most common diagnoses were minor trauma 130 (42%) and ethanol or illicit drug intoxication 98 (32%). Of the patients treated, 147 (48%) admitted to using illicit drugs or ethanol while attending the concerts. The median time spent in the first aid station was 15 +/- 22.5 minutes (range, 5 to 150 minutes). One hundred patients (32.5%) were treated and released, 98 (32%) were transported to emergency departments, and 110 (35.5%) signed out against medical advice. CONCLUSION: Minor trauma and the use of illicit drugs and ethanol were common in spectators presenting to first aid stations at these concert events. Physicians and paramedical personnel working at rock concerts should be aware of the current drug use patterns and should be trained in treating such drug use.

Acute renal toxicity after ingestion of Lava light liquid.

A 65-year-old man with a history of alcohol abuse and seizure disorder presented to the emergency department with altered mental status, increased anion gap acidosis, phenytoin toxicity, and acute kidney failure. The patient had ingested the liquid contents of a Lava light, which contained chlorinated paraffin, polyethylene glycol (molecular weight 200), kerosene, and micro-crystalline wax. Gas chromatography-mass spectrophotometry of the patient's blood produced results consistent with the same analysis of the Lava light contents. After 3 days of declining mental status and worsening kidney function, the patient required hemodialysis. After a prolonged hospitalization, the patient was discharged home with residual renal insufficiency. Although multifactorial, the associated renal toxicity was most probably related to the low molecular weight polyethylene glycol content of the lamp's liquid contents.

The price of gold: mercury exposure in the Amazonian rain forest.

Concern has surfaced over the recent discovery of human mercury exposure throughout the tropical rain forest of South America's Amazon River Basin. The probable source of mercury has been traced to gold mines located within the interior. The mining process involves the extraction of gold from ore by burning off a mercury additive, resulting in vaporization of elemental mercury into the surrounding environment. The purpose of this case series is to document mercury levels in miners and local villagers presenting with a history of exposure, or signs and symptoms consistent with mercury toxicity. Over a five year period (1986-91), the whole blood and urine mercury levels of 55 Brazilian patients demonstrating signs and symptoms consistent with mercury exposure were collected. Thirty-three (60%) of the subjects had direct occupational exposure to mercury via gold mining and refining. Whole blood mercury levels ranged from 0.4-13.0 micrograms/dL (mean 3.05 micrograms/dL). Spot urine levels ranged 0-151 micrograms/L (mean = 32.7 micrograms/L). Occupational mercury exposure is occurring in the Amazon River Basin. Interventions aimed at altering the gold mining process while protecting the workers and surrounding villagers from the source of exposure are essential. The impact of the gold mining industry on general environmental contamination has not been investigated.

Chronic phencyclidine abuse and physical assault.

When the authors investigated aggressive behavior on a phencyclidine (PCP) detoxification and rehabilitation unit and compared similar types of behavior on a heroin unit, they found no differences between the two units. The urinary PCP levels of a subgroup of 75 patients admitted to the PCP unit who had PCP-positive urine were significantly higher than those of 75 patients admitted to an acute psychiatric ward because of violent behavior who also had PCP-positive urine. The authors discuss the implications of these findings and the need for more information on the relationship between PCP levels in blood and urine and behavior.