SNAPSHOT USA 2021: A third coordinated national camera trap survey of the United States.

SNAPSHOT USA is a multicontributor, long-term camera trap survey designed to survey mammals across the United States. Participants are recruited through community networks and directly through a website application (https://www.snapshot-usa.org/). The growing Snapshot dataset is useful, for example, for tracking wildlife population responses to land use, land cover, and climate changes across spatial and temporal scales. Here we present the SNAPSHOT USA 2021 dataset, the third national camera trap survey across the US. Data were collected across 109 camera trap arrays and included 1711 camera sites. The total effort equaled 71,519 camera trap nights and resulted in 172,507 sequences of animal observations. Sampling effort varied among camera trap arrays, with a minimum of 126 camera trap nights, a maximum of 3355 nights, a median 546 nights, and a mean 656 ± 431 nights. This third dataset comprises 51 camera trap arrays that were surveyed during 2019, 2020, and 2021, along with 71 camera trap arrays that were surveyed in 2020 and 2021. All raw data and accompanying metadata are stored on Wildlife Insights (https://www.wildlifeinsights.org/), and are publicly available upon acceptance of the data papers. SNAPSHOT USA aims to sample multiple ecoregions in the United States with adequate representation of each ecoregion according to its relative size. Currently, the relative density of camera trap arrays varies by an order of magnitude for the various ecoregions (0.22-5.9 arrays per 100,000 km2), emphasizing the need to increase sampling effort by further recruiting and retaining contributors. There are no copyright restrictions on these data. We request that authors cite this paper when using these data, or a subset of these data, for publication. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the US Government.

Increasing the precision of simulated percutaneous dilatational tracheostomy-a pilot prototype device development study.

Percutaneous dilatational tracheostomy (PDT) is a bedside medical procedure which sites a new tracheostomy tube in the front of the neck. The critical first step is accurate placement of a needle through the neck tissues into the trachea. Misplacement occurs in around 5% of insertions, causing morbidity, mortality, and delays to recovery. We aimed to develop and evaluate a prototype medical device to improve precision of initial PDT-needle insertion. The Guidance for Tracheostomy (GiFT) system communicates the relative locations of intra-tracheal target sensor and PDT-needle sensor to the operator. In simulated "difficult neck" models, GiFT significantly improved accuracy (mean difference 10.0 mm, ANOVA p < 0.001) with ten untrained laboratory-based participants and ten experienced medical participants. GiFT resulted in slower time-to-target (mean difference 56.1 s, p < 0.001) than unguided attempts, considered clinically insignificant. Our proof-of-concept study highlights GiFT's potential to significantly improve PDT accuracy, reduce procedural complications and offer bedside PDT to more patients.

A novel camera trapping method for individually identifying pumas by facial features.

Camera traps (CTs), used in conjunction with capture-mark-recapture analyses (CMR; photo-CMR), are a valuable tool for estimating abundances of rare and elusive wildlife. However, a critical requirement of photo-CMR is that individuals are identifiable in CT images (photo-ID). Thus, photo-CMR is generally limited to species with conspicuous pelage patterns (e.g., stripes or spots) using lateral-view images from CTs stationed along travel paths. Pumas (Puma concolor) are an elusive species for which CTs are highly effective at collecting image data, but their suitability to photo-ID is controversial due to their lack of pelage markings. For a wide range of taxa, facial features are useful for photo-ID, but this method has generally been limited to images collected with traditional handheld cameras. Here, we evaluate the feasibility of using puma facial features for photo-ID in a CT framework. We consider two issues: (1) the ability to capture puma facial images using CTs, and (2) whether facial images improve human ability to photo-ID pumas. We tested a novel CT accessory that used light and sound to attract the attention of pumas, thereby collecting face images for use in photo-ID. Face captures rates increased at CTs that included the accessory (n = 208, χ 2 = 43.23, p ≤ .001). To evaluate if puma faces improve photo-ID, we measured the inter-rater agreement of 5 independent assessments of photo-ID for 16 of our puma face capture events. Agreement was moderate to good (Fleiss' kappa = 0.54, 95% CI = 0.48-0.60), and was 92.90% greater than a previously published kappa using conventional CT methods. This study is the first time that such a technique has been used for photo-ID, and we believe a promising demonstration of how photo-ID may be feasible for an elusive but unmarked species.

A comparison of regional brain volumes and white matter connectivity in subjects with stimulant induced psychosis versus schizophrenia.

RATIONALE: Schizophrenia and stimulant-induced psychosis (SIP) represent two different forms of psychotic disorder, with different etiologies. While many of the symptoms of psychosis are common to both disorders, there have been few direct comparisons between these conditions, especially when controlling for stimulant use in individuals with schizophrenia. OBJECTIVES: We directly compared both psychotic disorders with a comprehensive battery of clinical, neurocognitive and neuroanatomical measures. This included one group with SIP (and concurrent stimulant dependence) and two groups with schizophrenia (either with or without concurrent stimulant dependence). METHODS: Ninety-six participants were recruited from a marginalized urban population, which included 39 with SIP (and concurrent stimulant dependence), 18 with schizophrenia (without stimulant dependence), and 39 with schizophrenia (with concurrent stimulant dependence). All subjects had extensive clinical and neurocognitive evaluations, complemented with structural MRI including diffusion tensor imaging (DTI) sequences to determine regional brain volumes and white matter connectivity. RESULTS: Both positive and negative symptoms were greater in the SZ-dependent group than the other two. Neurocognitive function was broadly similar. The structural brain imaging revealed lateralized changes to the left parietal/temporal lobe, in which regional volumes were smaller in the SZ-dependent than the SZ-non-dependent group. DTI analysis indicated extensive decreases in fractional anisotropy, with parallel increases in radial diffusivity, in the SIP group compared to the SZ-dependent group. CONCLUSIONS: These findings reveal both similarities and differences between SIP and schizophrenia. Furthermore, schizophrenia with concurrent stimulant dependence may be associated with a different clinical and neuroanatomical profile as compared to schizophrenia alone.

A comparison of psychotic symptoms in subjects with methamphetamine versus cocaine dependence.

RATIONALE: The psychostimulant drugs cocaine and methamphetamine are potent indirect dopamine receptor agonists which act through similar but not identical mechanisms. Studies in humans have observed that a large proportion of those who chronically use these drugs experience psychotic symptoms. However, direct comparisons of psychotic symptom severity between cocaine and methamphetamine users are lacking. OBJECTIVES: The goal of the present study was to directly compare severity of psychotic symptoms between cocaine- and methamphetamine-dependent individuals. Additionally, we sought to determine how concurrent cocaine + methamphetamine dependence would influence psychotic symptoms. METHODS: We recruited 153 polysubstance-using subjects meeting DSM-IV-TR criteria for cocaine dependence, 38 with methamphetamine dependence, and 32 with cocaine + methamphetamine dependence. Psychotic symptoms were assessed with the Positive and Negative Syndrome Scale (PANSS) and analyzed using a five-factor model. All participants were also assessed for physical and mental illnesses as well as recent substance use. Most subjects completed a comprehensive neurocognitive battery. RESULTS: While all three groups exhibited high total PANSS scores, the positive symptom subscale was significantly higher in the methamphetamine-dependent (17.03 ± 6.3) than the cocaine-dependent group (13.51 ± 4.12) and non-significantly higher (p = 0.08) than the cocaine + methamphetamine group (14.44 ± 5.50). Groups also differed on demographic variables, viral infection, and other indices of substance use, which were unlikely to account for the difference in positive symptoms. There were only modest differences between groups in neurocognitive function. CONCLUSIONS: Methamphetamine dependence was associated with more severe positive symptoms of psychosis than cocaine dependence. Concurrent cocaine + methamphetamine dependence did not increase psychosis severity.

Association of haemodynamic changes measured by serial central venous saturation during ultrafiltration for acutely decompensated heart failure with diuretic resistance and change in renal function.

BACKGROUND: Patients with acute decompensated heart failure with diuretic resistance (ADHF-DR) have a poor prognosis. The aim of this study was to assess in patients with ADHF-DR, whether haemodynamic changes during ultrafiltration (UF) are associated with changes in renal function (Δcreatinine) and whether Δcreatinine post UF is associated with mortality. METHODS: Seventeen patients with ADHF-DR underwent 20 treatments with UF. Serial bloods (4-6 hourly) from the onset of UF treatment were measured for renal function, electrolytes and central venous saturation (CVO2). Univariate and multivariate analysis were performed to assess the relationship between changes in markers of haemodynamics [heart rate (HR), systolic blood pressure (SBP), packed cell volume (PCV) and CVO2] and Δcreatinine. Patients were followed up and mortality recorded. Cox-regression survival analysis was performed to determine covariates associated with mortality. RESULTS: Renal function worsened after UF in 17 of the 20 UF treatments (baseline vs. post UF creatinine: 164±58 vs. 185±69µmol/l, P<0.01). ΔCVO2 was significantly associated with Δcreatinine [ß-coefficient of -1.3 95%CI (-1.8 to -0.7), P<0.001] and remained significantly associated with Δcreatinine after considering changes in SBP, HR and PCV [P<0.001]. Ten (59%) patients died at 1-year and 15(88%) by 2-years. Δcreatinine was independently associated with mortality (adjusted-hazard ratio 1.03 (1.01 to 1.07) per 1µmol/l increase in creatinine; P=0.02). CONCLUSIONS: Haemodynamic changes during UF as measured by the surrogate of cardiac output was associated with Δcreatinine. Worsening renal function at end of UF treatment occurred in the majority of patients and was associated with mortality.