An approach to rapid processing of camera trap images with minimal human input.

Camera traps have become an extensively utilized tool in ecological research, but the manual processing of images created by a network of camera traps rapidly becomes an overwhelming task, even for small camera trap studies.We used transfer learning to create convolutional neural network (CNN) models for identification and classification. By utilizing a small dataset with an average of 275 labeled images per species class, the model was able to distinguish between species and remove false triggers.We trained the model to detect 17 object classes with individual species identification, reaching an accuracy up to 92% and an average F1 score of 85%. Previous studies have suggested the need for thousands of images of each object class to reach results comparable to those achieved by human observers; however, we show that such accuracy can be achieved with fewer images.With transfer learning and an ongoing camera trap study, a deep learning model can be successfully created by a small camera trap study. A generalizable model produced from an unbalanced class set can be utilized to extract trap events that can later be confirmed by human processors.

Endogenous angiotensins and catecholamines do not reduce skin blood flow or prevent hypotension in preterm piglets.

Endocrine control of cardiovascular function is probably immature in the preterm infant; thus, it may contribute to the relative ineffectiveness of current adrenergic treatments for preterm cardiovascular compromise. This study aimed to determine the cardiovascular and hormonal responses to stress in the preterm piglet. Piglets were delivered by cesarean section either preterm (97 of 115 days) or at term (113 days). An additional group of preterm piglets received maternal glucocorticoids as used clinically. Piglets were sedated and underwent hypoxia (4% FiO2 for 20 min) to stimulate a cardiovascular response. Arterial blood pressure, skin blood flow, heart rate and plasma levels of epinephrine, norepinephrine, angiotensin II (Ang II), angiotensin-(1-7) (Ang-(1-7)), and cortisol were measured. Term piglets responded to hypoxia with vasoconstriction; preterm piglets had a lesser response. Preterm piglets had lower blood pressures throughout, with a delayed blood pressure response to the hypoxic stress compared with term piglets. This immature response occurred despite similar high levels of circulating catecholamines, and higher levels of Ang II compared with term animals. Prenatal exposure to glucocorticoids increased the ratio of Ang-(1-7):Ang II. Preterm piglets, in contrast to term piglets, had no increase in cortisol levels in response to hypoxia. Preterm piglets have immature physiological responses to a hypoxic stress but no deficit of circulating catecholamines. Reduced vasoconstriction in preterm piglets could result from vasodilator actions of Ang II. In glucocorticoid exposed preterm piglets, further inhibition of vasoconstriction may occur because of an increased conversion of Ang II to Ang-(1-7).

Effects of glucocorticoid exposure on growth and structural maturation of the heart of the preterm piglet.

Inadequate maintenance of systemic blood flow in neonates following preterm birth is associated with increased morbidity and mortality, and may be due in part to structural immaturity of the myocardium. Maternal glucocorticoid administration is associated with improved cardiovascular function, and possibly promotes structural maturation of the myocardium. This study assessed the structural maturity of the myocardium in male and female preterm and term piglets, and preterm piglets exposed to a regimen of maternal glucocorticoids as used clinically. In preterm, term and glucocorticoid exposed preterm piglets cardiomyocyte maturity was examined by measuring the proportion of binucleated myocytes and the volumes of single living ventricular cardiomyocytes with fluorescence microscopy. Ventricular apoptosis and proliferation were measured by immunohistochemistry. Preterm piglet hearts had fewer binucleated myocytes, smaller myocytes, and more proliferative and fewer apoptotic nuclei than term hearts. Maternal glucocorticoid treatment resulted in increased binucleation with no increase in myocyte volume, and levels of proliferation and apoptosis that were more similar to the term heart. Atrial weights were increased and in female piglets there was an increase in the ratio of left to right ventricular weight. The observed changes in atrial mass and myocyte structural maturation correlated with changes in cardiac function of isolated hearts of littermates. In conclusion, the association between increased myocardial maturation following glucocorticoid exposure, improved cardiac function in littermates, and clinical improvement in human neonatal cardiac function exposed to antenatal glucocorticoids, suggests that glucocorticoid exposure contributes to improved cardiovascular function in preterm infants by promoting myocardial structural maturity.

A pig model of the preterm neonate: anthropometric and physiological characteristics.

BACKGROUND: Large animal models are an essential tool in the development of rationally-based new clinical therapies for preterm infants. We provide a description of the newborn pig as a model of the preterm neonate in terms of growth parameters, physiology and the requirement for intensive care over a range of gestational ages. METHODS: Twenty-nine litters of piglets (n = 298) were delivered by caesarean section at six timepoints during gestation from 91d to 113d (term = 115d). Two groups, at 91 and 97d gestation, also received maternal glucocorticoid treatment. At four of these timepoints, piglets (n = 79) were ventilated, sedated and monitored using standard neonatal intensive care techniques for up to 8 h in various experimental protocols. RESULTS: Body weight increased from mean 697 g (SD 193) at 91d gestation to 1331 g (SD 368) at 113d gestation. Piglets delivered at 97d gestation were able to be resuscitated and kept alive for at least 8 h on respiratory support after surfactant administration. Maternal glucocorticoid treatment 48 h and 24 h hours prior to delivery reduced the requirement for ventilator support and improved cardiovascular stability. CONCLUSION: The pig provides a relevant model for the study of human preterm physiology and for investigation of novel therapies to improve outcomes.

Youth living on Hispanic-operated farms: injuries and population estimates in the U.S., 2000.

A dearth of information exists in public health surveillance on the injury burden among Hispanic farm youth in the U.S. In this study, data were collected via a telephone survey with Hispanic farm operators sampled from the 1991 Census of Agriculture active list of farms. There were an estimated 307 nonfatal injuries among an estimated 21,631 youth less than 20 years old living on Hispanic-operated farms in the U.S., 2000. Males accounted for 73% of the injuries and had an injury rate of 20.2 compared to 8.2 per 1,000 for females. Injury rates were higher for work-related incidents than for nonwork, and this relationship was true for both males and females. Work and nonwork injury rates were also similar for youth < 10 and 10-15 years old, but for youth 16-19 years of age, the risk of injury for work-related incidents was higher than for nonwork. Livestock operations had a larger number of injuries and higher injury rates compared to crop operations. These data provide previously unavailable descriptive statistics for both the nonfatal injury burden and population estimate for youth on Hispanic-operated farms.

Nonfatal injuries to household youth on racial minority-operated farms in the U.S., 2000.

The National Institute for Occupational Safety and Health (NIOSH) estimated that 32,808 nonfatal injuries occurred to youth less than 20 years of age on U.S. farms during 1998. These data, however, do not allow for the identification of minority farm operators. The Minority Farm Operator Childhood Agricultural Injury Survey (M-CAIS) was conducted to provide an overview of the number of youth on minority-operated farms and their associated farm-related injuries during 2000. M-CAIS was conducted by the USDA for NIOSH through a telephone survey of 49,270 minority-operated farms identified in the 1997 Census of Agriculture. These minority-operated farms included four racial categories (black, Asian, Native American, and other) and operators of Hispanic ethnicity. This study included only racial minority-operated farms for analysis, white Hispanic farms were excluded. In 2000, there were an estimated 28,577 youth living on U.S. farms operated by racial minorities. In that year, these youth sustained an estimated 348 nonfatal injuries. Males accounted for 245 (70%) of the injuries to household youth. The majority of all injuries to household youth (247, 71%) occurred on livestock operations. Native American household youth accounted for both the largest number of injuries (177) and the highest rate of injury (24.0/1,000 household youth) on these farms. M-CAIS data indicated significant variation in injury rates among specific racial categories. Results of the M-CAIS suggest the need for prevention strategies to address issues found within these specific sub-populations of the agricultural community.

Activity-dependent maintenance and growth of dendrites in adult cortex.

Whereas it is widely accepted that the adult cortex is capable of a remarkable degree of functional plasticity, demonstrations of accompanying structural changes have been limited. We examined the basal dendritic field morphology of dye-filled neurons in layers III and IV of the mature barrel cortex after vibrissal-deafferentation in adult rats. Eight weeks later, the tendency for these neurons to orient their dendritic arbors toward the center of their home barrel was found to be disrupted by the resultant reduced activity of thalamocortical innervation. Measures of spine density and total dendritic length were normal, indicating that the loss of dendritic bias was accompanied by growth of dendrites directed away from the barrel center. This finding suggests that in the mature cortex, the apparently static structural attributes of the normal adult cortex depend on maintenance of patterns of afferent activity; with the corollary that changes in these patterns can induce structural plasticity.

The type 1 polyaxonal amacrine cells of the rabbit retina: a tracer-coupling study.

The type 1 polyaxonal (PA1) cell is a distinct type of axon-bearing amacrine cell whose soma commonly occupies an interstitial position in the inner plexiform layer; the proximal branches of the sparse dendritic tree produce 1-4 axon-like processes, which form an extensive axonal arbor that is concentric with the smaller dendritic tree (Dacey, 1989; Famiglietti, 1992a,b). In this study, intracellular injections of Neurobiotin have revealed the complete dendritic and axonal morphology of the PA1 cells in the rabbit retina, as well as labeling the local array of PA1 cells through homologous tracer coupling. The dendritic-field area of the PA1 cells increased from a minimum of 0.15 mm2 (0.44-mm equivalent diameter) on the visual streak to a maximum of 0.67 mm2 (0.92-mm diameter) in the far periphery; the axonal-field area also showed a 3-fold variation across the retina, ranging from 3.1 mm2 (2.0-mm diameter) to 10.2 mm2 (3.6-mm diameter). The increase in dendritic- and axonal-field size was accompanied by a reduction in cell density, from 60 cells/mm2 in the visual streak to 20 cells/mm2 in the far periphery, so that the PA1 cells showed a 12 times overlap of their dendritic fields across the retina and a 200-300 times overlap of their axonal fields. Consequently, the axonal plexus was much denser than the dendritic plexus, with each square millimeter of retina containing approximately 100 mm of dendrites and approximately 1000 mm of axonal processes. The strong homologous tracer coupling revealed that approximately 45% of the PA1 somata were located in the inner nuclear layer, approximately 50% in the inner plexiform layer, and approximately 5% in the ganglion cell layer. In addition, the Neurobiotin-injected PA1 cells sometimes showed clear heterologous tracer coupling to a regular array of small ganglion cells, which were present at half the density of the PA1 cells. The PA1 cells were also shown to contain elevated levels of gamma-aminobutyric acid (GABA), like other axon-bearing amacrine cells.

Topographic plasticity in primary visual cortex is mediated by local corticocortical connections.

The placement of monocular laser lesions in the adult cat retina produces a lesion projection zone (LPZ) in primary visual cortex (V1) in which the majority of neurons have a normally located receptive field (RF) for stimulation of the intact eye and an ectopically located RF (displaced to intact retina at the edge of the lesion) for stimulation of the lesioned eye. Animals that had such lesions for 14-85 d were studied under halothane and nitrous oxide anesthesia with conventional neurophysiological recording techniques and stimulation of moving light bars. Previous work suggested that a candidate source of input, which could account for the development of the ectopic RFs, was long-range horizontal connections within V1. The critical contribution of such input was examined by placing a pipette containing the neurotoxin kainic acid at a site in the normal V1 visual representation that overlapped with the ectopic RF recorded at a site within the LPZ. Continuation of well defined responses to stimulation of the intact eye served as a control against direct effects of the kainic acid at the LPZ recording site. In six of seven cases examined, kainic acid deactivation of neurons at the injection site blocked responsiveness to lesioned-eye stimulation at the ectopic RF for the LPZ recording site. We therefore conclude that long-range horizontal projections contribute to the dominant input underlying the capacity for retinal lesion-induced plasticity in V1.

Nonfatal work-related inhalations: surveillance data from hospital emergency departments, 1995-1996.

BACKGROUND: Data from a stratified sample of hospital emergency rooms in the USA were used to describe nonfatal work-related inhalation injuries and illnesses during July 1995 to July 1996. METHODS: Information was abstracted from emergency room records by the Consumer Product Safety Commission (CPSC) as part of the National Electronic Injury Surveillance System (NEISS) for all work-related injuries and illnesses regardless of product involvement. RESULTS: There were an estimated 44,423 occupational inhalation cases nationwide, with an annual rate of 3.6 cases/10(4) workers/year. The rate for men (4.4 cases/10(4)) was greater than that observed for women (2.6 cases/10(4)), and the rates tended to decline with increasing age. An estimated 4.6% of the cases were hospitalized for further treatment. The highest rate by industry was 16.4 cases/10(4) for public administration (which included fire and police departments). Among non-firefighters, there were an estimated 6,470 cases nationwide in which respiratory symptoms or conditions were noted, which yielded an annual rate of 0.5 cases/10(4) (95% CI 0.3, 0.7). Chlorine compounds were a common agent for the cases with adverse respiratory outcomes. CONCLUSIONS: The NEISS data provide an efficient method to learn about the national frequency of work-related inhalation injuries and illnesses. The National Institute for Occupational Safety and Health (NIOSH) is exploring two ways to use these data: first, to routinely review the reports to conduct surveillance for work-related inhalation cases; and second, to consider working with CPSC to conduct follow-back interviews of selected cases in order to learn more about the circumstances of the exposure, prior training of the case, and outcome of the exposure. Am. J. Ind. Med. 38:140-148, 2000. Published 2000 Wiley-Liss, Inc.

Adolescent occupational injuries in fast food restaurants: an examination of the problem from a national perspective.

Work injuries to adolescents are most prevalent in the retail trades industry, with a large portion occurring in eating and drinking establishments (E&DEs). Data from the National Electronic Injury Surveillance System were examined for nonfatal injuries to adolescents, ages 14 through 17, injured while working in fast food restaurants (a subcategory of E&DEs) from July 1, 1992, to June 30, 1994. There were an estimated 44,765 adolescent injuries in E&DEs, with an estimated 27,997 in fast food restaurants, during this period. The injury rate for E&DEs in the 15 through 17 age group was higher than for all other industries combined (rate ratio [RR] = 1.7), with little disparity in rates between the sexes. This study identifies the fast food industry as the source of a large proportion of occupational injuries to adolescents, and indicates that task-specific risk factors seem to be strongly related to sex.

A descriptive analysis of nonfatal occupational injuries to older workers, using a national probability sample of hospital emergency departments.

An estimated 136,985 nonfatal, work-related injuries to workers 55 years of age and older were presented for treatment in hospital emergency departments across the United States during 1993. Men accounted for 63.7% of the injuries and had an injury rate of 1.06 per 100 workers, compared with a rate of 0.76 among women. Among the oldest workers (65+ years), injuries were more likely to be fractures or dislocations, to result from falls on the same level, or to involve hospitalization. The services industry had the largest number of injuries (31.9%), whereas the highest injury rate occurred in the agriculture/forestry/fishing industry (1.50 per 100 workers). The types of injuries most frequently requiring hospitalization were fractures or dislocations that resulted from a fall. Because older workers' employment demographics and injury patterns differ from the remainder of the labor force, interventions need to be developed which are specific to the workplace for this older working population.

Three perspectives on work-related injury surveillance systems.

This paper reviews surveillance approaches for occupational injuries and evaluates three emerging methodologies for the enhancement of work-related injury surveillance: (1) narrative data analysis, (2) data set linkage, and (3) comprehensive company-wide surveillance systems. All three methods are the result of new applications of computer hardware and software that have apparent strengths and limitations. A major strength is the improved description of work exposures and related injuries leading to better understanding of injury etiology. This understanding, however, is limited by the data quality and completeness entered on records at the time of the injury. We recommend (1) more widespread inclusion of narrative text in databases, analyses of which can be a valuable supplement to injury coded data; (2) the increased use of data set linkage studies to combine injury and work-history data; and (3) the development of comprehensive company-wide surveillance systems to expedite the use of epidemiologic data for occupational injury prevention activities. Further development of these methods and others is encouraged, especially in light of technological advancements in data capture, analysis and presentation. Only through such efforts can we best apply epidemiologic principles to preventing injuries in the workplace.

"How's the baby doing?" Struggling with narratives of progress in a neonatal intensive care unit.

In this at once biographical and autobiographical piece (cf. Shapiro 1988), I describe the processes of "knowledge-making" of one neonatal intensive care parent. In particular, I investigate the ways that narratives of linear progress informed my efforts to understand my son's condition and future prospects, that is, to engage in lay prognostication. In examining and comparing the three metaphors most commonly used to describe my son's changing condition-roller coaster, graduation, and course-I explore how the discrepancy between narratives of linear progress and the complex and volatile condition of many premature and/or critically ill babies is discursively managed in a neonatal intensive care unit.

Cardiac asystoles in preterm infants: are these a risk factor for SIDS? - abstract

In spite of significant advances in perinatal/neonatal care, preterm infants remain at high risk for unexplained death in infancy. Using continous documented monitoring as a predischarge screen for persistance of apneas and bradycardias in preterm infants (mean GA 30.5 weeks) prior to hospital discharge, 21 of 332 infants (6.3 per cent) had asystolic events defined as cardiac pauses > 3 seconds. All affected infants had a history of O2 desaturation < 85 per cent and/or colour change in the weeks prior to event monitor screening. Concurrent 72-hour Holter monitoring confirmed sinus pauses of 3 - 10 seconds. Echocardiogram revealed pulmonary artery branch stenosis in 9 of the 21 infants, but no other structural abnormalities. Gastroesophageal reflux was diagnosed by pH probe and/or Milk-Scan in all 21 infants; clinical symptoms improved after specific therapy but asystoles and bradycardias persisted. All infants were followed with home monitoring until asystole-free for 2 months. Asystoles decreased with age: with a mean of 33.7 events/wk at 36 wks post-conceptional age, 24.7 at 47 wks and only 1 infant had asystolic events beyond 58 weeks. Pacemakers were recommended in 3 infants, but only placed in one. None of the infants died. Conclusion: asystolic events occur in preterm infants without significant anatomical cardiac abnormalities and can be diagnosed by continuous documented monitoring. Resolution occurs spontaneously, but long-term cardiology follow-up is necessary to determine later outcome and complications. The significance of these events and their relationship to sudden death in infancy need to be explored (AU)

True apenas as a first symptom of viral upper respiratory tract infection in preterm infants on home documented event monitors - abstract

Between January, 1992 and September, 1994 all preterm infants followed in the Neonatal High-risk Follow-up Clinic were prospectively evaluated for apneas and/or bradycardias associated with upper respiratory tract infection (URI). 52 infants (mean post-conceptional age 39.2 weeks) had increased apneas with URI. All infants had nasal stuffiness; dry cough was present in 10 (19 percent) and 12 (23 percent) had low grade fever, 16 (31 percent) slept more and had to be awakened for feeds. Respiratory syncytial virus (RSV) antigen was negative in 40; 12 were RSV positive. All bacterial cultures were negative. Hospitalization was necessary in 23 infants (5 with RSV and 19 without RSV). The 9 infants on xanthine therapy had therapeutic levels. The onset of apneas and bradycardias was abrupt, apneas (by report and monitor data) preceded parental suspicion of URI. Monitor data showed 0-5 apneas > 20 sec. per during URI. In addition, 22 percent of infants demonstrated bradycardias with heart rates < 80 minute with URI. Continous pulse oximetry on hospitalized infants showed baseline levels of 93-98 percent with frequent desaturations as low as 78 percent, requiring O 2 supplementation in 14 infants and Xanthine therapy in 16. None of the infants expired. Ex-preterm infants on home monitoring for persistence of apnea of prematurity may be at a high risk for severe apneas and bradycardias with viral upper respiratory infection, and require close surveillance whenever exposed. The relationship of this to SIDS/ALTE needs to be investigated (AU)

A detailed analysis of work-related injury among youth treated in emergency departments.

Telephone interviews were conducted with 146 14- to 16-year-olds who incurred an occupational injury treated in an emergency department during the period July through September 1992. Thirty-two percent of the injuries occurred as the result of using equipment. Over half the workers reported not having received prior training on how to avoid injury. The injury limited normal activities for at least 1 day for 68% of the youth and for more than a week for 25%, corresponding to an estimated 6,208 (95% CI: 4,277, 8,139) and 2,639 (95% CI: 1,580, 3,699) youths nationwide, respectively. Employment in retail trades, equipment use, lack of training, and burn injuries were associated with increased limitation of normal activities. Nineteen percent of the youths appear to have been injured in jobs declared to be hazardous, or typically prohibited for their age (14- and 15-year-olds) under federal child labor laws. The prohibited job directly contributed to the injury in 64% of these cases.

Occupational injury deaths of 16- and 17-year-olds in the United States.

Data from the National Traumatic Occupational Fatalities surveillance system were used to analyze occupational injury deaths of civilian 16- and 17-year-olds during 1980 through 1989. There were 670 deaths; the rate was 5.11 per 100,000 full-time equivalent workers. The leading causes of death were incidents involving motor vehicles and machines, electrocution, and homicide. Workers 16 and 17 years old appear to be at greater risk than adults for occupational death by electrocution, suffocation, drowning, poisoning, and natural and environmental factors. Improved enforcement of and compliance with federal child labor laws, evaluation of the appropriateness of currently permitted activities, and education are encouraged.