Portable thermal scanners to detect and monitor small endotherms: A comparative assessment of available equipment to guide practitioners.

Detection is essential to studying and monitoring wild animals; however, detection is challenging for small endotherms that are nocturnal or best detected at night. Techniques such as trapping or spotlighting disturb focal species, and the effectiveness of spotlighting can be limited for cryptic species, resulting in low detection rates that hinder our ability to monitor and study some endotherms at night. Thermal scanners detect infrared wavelengths not otherwise visible to humans. With improvements in equipment size and cost, thermal scanners have emerged as a valuable tool for passive detection of endotherms. Here we seek to provide objective guidance on thermal tool selection to practitioners who wish to adopt such tools to detect and monitor small endotherms. We compared the efficacy of three handheld thermal scanners (of varying resolutions) and a traditional spotlight for detecting small, cryptic endotherms at night. Random arrays of artificially heated small bird models (representing small, cryptic endotherms) were established along transects in native grasslands that support a range of small threatened endotherms, including the Critically Endangered Plains-wanderer (Pedionomus torquatus). Transects were independently surveyed by five observers, blind to model locations and model density. Performance measures representing detection capability were assessed for all devices, and usability of each device was assessed with a survey completed by all observers. Detection rates, detection distances, and survey accuracy were greater for thermal scanners with resolutions of 320 × 240 and 640 × 480 than for the spotlight. A low-resolution thermal scope (160 × 120) performed poorly for all performance measures. There was a consensus among users that a video camera-style thermal scanner was most comfortable to hold and view while traversing the transect, as opposed to thermal scopes where users look directly through the lens. These results suggest that high-resolution thermal scanners (≥320 × 240) provide improved detection capabilities compared to traditional spotlights. Higher detection rates provide opportunities for detecting and monitoring small endotherms at night where this was once difficult or impossible.

Routine Laboratory Tests are not Necessary After Primary Total Joint Arthroplasty: A Prospective Study Utilizing a Selective Algorithmic Approach.

BACKGROUND: Laboratory tests are obtained following total joint arthroplasty (TJA) despite a lack of supporting evidence. No prior study has prospectively analyzed the effect of discontinuing routine laboratory tests. This study aimed to determine whether discontinuing routine laboratory tests in TJA patients resulted in a difference in 90-day complications. METHODS: This was a prospective protocol change study at a high-volume center. Prior to protocol change, patients underwent routine laboratory tests following primary unilateral TJA (control group). After the change, an algorithmic approach was used to selectively order laboratory tests (protocol group). Patients with bleeding disorders, chronic obstructive pulmonary disease, arrhythmia, coronary artery disease, congestive heart failure, chronic renal failure, dementia, abnormal preoperative sodium, potassium, or hemoglobin <10 g/dL were excluded. In-hospital and 90-day data were collected. Student's t-test was used to analyze continuous variables and chi-squared test was used for categorical variables. A pre-hoc analysis examining the primary outcome required 607 patients per group to achieve 80% power. RESULTS: The protocol group included 937 patients, whereas the control group included 891 patients. The protocol group had fewer females and total hip arthroplasties. There were no differences in age, body mass index, American Society of Anesthesiologists classification, tranexamic acid administration, or estimated blood loss between the protocol and control groups. There were also no differences in transfusions, electrolyte corrections, unplanned consults, length of stay, or transfers. The protocol cohort had more fluid boluses and home discharges. There was no difference in 90-day complications between the 2 groups. CONCLUSIONS: This study utilizing an algorithmic approach to laboratory collection demonstrates that discontinuing routine laboratory tests following TJA is safe and effective. We believe this protocol can be implemented for most patients undergoing primary unilateral TJA.

An a posteriori Error Estimate for Scanning Electron Microscope Simulation with Adaptive Mesh Refinement.

The intensity variation in a scanning electron microscope is a complex function of sample topography and composition. Measurement accuracy is improved when an explicit accounting for the relationship between signal and measurand is made. Because the determinants of the signal are many, the theoretical understanding usually takes the form of a simulator. For samples with nonconducting regions that charge, one phase of the simulation is finite element analysis to compute the electric field. The size of the finite element mesh, and consequently computation time, can be reduced through the use of adaptive mesh refinement. We present a new a posteriori local error estimator and adaptive mesh refinement algorithm for the scanning electron microscope simulation. This error estimate is designed to minimize the error in the electron trajectories, rather than the energy norm of the error that traditional error estimators minimize. Using a test problem with a known exact solution, we show that the adaptive mesh can achieve the same error in electron trajectories as a carefully designed hand-graded mesh while using 3.5 times fewer vertices and 2.25 times less computation time.

Resonant control of polar molecules in individual sites of an optical lattice.

We study the resonant control of two nonreactive polar molecules in an optical lattice site, focusing on the example of RbCs. Collisional control can be achieved by tuning bound states of the intermolecular dipolar potential by varying the applied electric field or trap frequency. We consider a wide range of electric fields and trapping geometries, showing that a three-dimensional optical lattice allows significantly wider avoided crossings than free space or quasi-two dimensional geometries. Furthermore, we find that dipolar confinement-induced resonances can be created with reasonable trapping frequencies and electric fields, and have widths that will enable useful control in forthcoming experiments.

Hamiltonian Paths Through Two- and Three-Dimensional Grids.

This paper addresses the existence of Hamiltonian paths and cycles in two-dimensional grids consisting of triangles or quadrilaterals, and three-dimensional grids consisting of tetrahedra or hexahedra. The paths and cycles may be constrained to pass from one element to the next through an edge, through a vertex, or be unconstrained and pass through either. It was previously known that an unconstrained Hamiltonian path exists in a triangular grid under very mild conditions, and that there are triangular grids for which there is no through-edge Hamiltonian path. In this paper we prove that a through-vertex Hamiltonian cycle exists in any triangular or tetrahedral grid under very mild conditions, and that there exist quadrilateral and hexahedral grids for which no unconstrained Hamiltonian path exists. The existence proofs are constructive, and lead to an efficient algorithm for finding a through-vertex Hamiltonian cycle.

The Refinement-Tree Partition for Parallel Solution of Partial Differential Equations.

Dynamic load balancing is considered in the context of adaptive multilevel methods for partial differential equations on distributed memory multiprocessors. An approach that periodically repartitions the grid is taken. The important properties of a partitioning algorithm are presented and discussed in this context. A partitioning algorithm based on the refinement tree of the adaptive grid is presented and analyzed in terms of these properties. Theoretical and numerical results are given.