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A laboratory study was performed using the Visible Oxford Space Environment Goniometer in which the broadband (350–1250 nm) bidirectional reflectance distribution functions (BRDFs) of two representative Apollo regolith samples were measured, for two surface roughness profiles, across a range of viewing angles—reflectance: 0–70°, in steps of 5°; incidence: 15°, 30°, 45°, and 60°; and azimuthal: 0°, 45°, 90°, 135°, and 180°. The BRDF datasets were fitted using the Hapke BRDF model to (1) provide a method of comparison to other photometric studies of the lunar regolith and (2) to produce Hapke parameter values which can be used to extrapolate the BRDF to all angles. Importantly, the surface profiles of the samples were characterized using an Alicona 3D® instrument, allowing two of the free parameters within the Hapke model, φ and θ¯, which represent porosity and surface roughness, respectively, to be constrained. The study determined that, for θ¯, the 500–1000 μm size‐scale is the most relevant for the BRDF. Thus, it deduced the following "best fit" Hapke parameters for each of the samples: Apollo 11 rough—w = 0.315 ± 0.021, b = 0.261 ± 0.007, and hS = 0.039 ± 0.005 (with θ¯ = 21.28° and φ = 0.41 ± 0.02); Apollo 11 smooth—w = 0.281 ± 0.028, b = 0.238 ± 0.008, and hS = 0.032 ± 0.006 (with θ¯ = 13.80° and φ = 0.60 ± 0.02); Apollo 16 rough—w = 0.485 ± 0.155, b = 0.155 ± 0.083, and hS = 0.135 ± 0.007 (with θ¯ = 21.69° and φ = 0.55 ± 0.02); Apollo 16 smooth—w = 0.388 ± 0.057, b = 0.063 ± 0.033, and hS = 0.221 ± 0.011 (with θ¯ = 14.27° and φ = 0.40 ± 0.02). Finally, updated hemispheric albedo functions were determined for the samples, which can be used to set laboratory measured visible scattering functions within thermal models. [ABSTRACT FROM AUTHOR]

A laboratory study was performed using the Visible Oxford Space Environment Goniometer in which the broadband (350–1250 nm) bidirectional reflectance distribution function (BRDF) of the Winchcombe meteorite was measured, across a range of viewing angles—reflectance: 0°–70°, in steps of 5°; incidence: 15°, 30°, 45°, and 60°; and azimuthal: 0°, 90°, and 180°. The BRDF dataset was fitted using the Hapke BRDF model to (1) provide a method of comparison to other meteorites and asteroids, and (2) to produce Hapke parameter values that can be used to extrapolate the BRDF to all angles. The study deduced the following Hapke parameters for Winchcombe: w = 0.152 ± 0.030, b = 0.633 ± 0.064, and hS = 0.016 ± 0.008, demonstrating that it has a similar w value to Tagish Lake (0.157 ± 0.020) and a similar b value to Orgueil (0.671 ± 0.090). Importantly, the surface profile of the sample was characterized using an Alicona 3D® instrument, allowing two of the free parameters within the Hapke model φ and θ¯, which represent porosity and surface roughness, respectively, to be constrained as φ = 0.649 ± 0.023 and θ¯ = 16.113° (at 500 μm size scale). This work serves as part of the characterization process for Winchcombe and provides a reference photometry dataset for current and future asteroid missions. [ABSTRACT FROM AUTHOR]

On the microscale, the Winchcombe CM carbonaceous chondrite contains a number of lithological units with a variety of degrees of aqueous alteration. However, an understanding of the average hydration state is useful when comparing to other meteorites and remote observations of airless bodies. We report correlated bulk analyses on multiple subsamples of the Winchcombe meteorite, determining an average phyllosilicate fraction petrologic type of 1.2 and an average water content of 11.9 wt%. We show the elemental composition and distribution of iron and iron oxidation state are consistent with measurements from other CM chondrites; however, Winchcombe shows a low Hg concentration of 58.1 ± 0.5 ng g−1. We demonstrate that infrared reflectance spectra of Winchcombe are consistent with its bulk modal mineralogy, and comparable to other CM chondrites with similar average petrologic types. Finally, we also evaluate whether spectral parameters can estimate H/Si ratios and water abundances, finding generally spectral parameters underestimate water abundance compared to measured values. [ABSTRACT FROM AUTHOR]

Introduction: The Winchcombe fall was observed on the 28th of February 2021 and ~600 g of meteoritic material was recovered over the following month [1]. Winchcombe is classified as a CM2 chondrite, though several lithologies are represented in the recovered material showing variations in petrologic type and degree of aqueous alteration. Analyses have been performed to gain a comprehensive understanding of its bulk material properties as part of a nationwide collaboration [e.g. 1, 2]. Here we discuss spectral analyses conducted at the Planetary Spectroscopy Facility at the University of Oxford. These measurements include visible to near-infrared (VNIR; 0.7-5 um) and mid-infrared (MIR; 5-25 um) reflectance measurements of two Winchcombe samples, as well as multi-angle VNIR Bidirectional Reflectance Distribution Function (BRDF) measurements made using the Visible Oxford Space Environment Goniometer [3]. The BRDF was measured for a powdered sample characterized in terms of porosity and surface roughness, and this dataset was used to determine the broadband albedo (0.35-1.25 um) of Winchcombe in [1]. IR Spectroscopy: Reflectance spectra of two samples (BM.2022,M1-91; BM.2022,M2-41) were measured with a Bruker VERTEX 70v Fourier Transform Infrared spectrometer, using a diffuse reflectance accessory under vacuum (~2 hPa) at 4 cm-1 resolution and an average of 150 scans calibrated to a diffuse gold target. The shortest wavelength range (0.8-2 μm) was acquired using an InGaAs detector coupled with a VIS/Quartz beamsplitter, while a RTDLaTGS detector and wide range beamsplitter were used for the near- and mid-infrared (2-25 μm). We correlate the spectra with modal mineralogy as determined using position-sensitive-detector X-ray diffraction (PSD-XRD) [1] and water abundance using thermogravimetric analysis (TGA) [2] for the same samples. A strong feature near 2.7 μm is attributed to OH-stretching, which indicates the aqueously altered mineralogy of the meteorite. It can also be affected by terrestrial alteration products and adsorbed water. Several studies [4,5,6] have used reflectance near this feature to estimate water content of asteroids and meteorites. We compared water abundances as measured through TGA to calculated water abundance using reflectance parameters and found reflectance measurements generally underestimated measured water abundance. The Christiansen feature (reflectance minimum) is located near 9 μm and indicates poor silicate polymerization. The shift in position between the two Winchcombe spectra (~0.1 um) correlates to slightly different olivine contents. The positions in the Winchcombe spectra are consistent with spectra of other CM chondrites [e.g. 7]. The transparency feature (reflectance maximum) near 11.5 um is another compositional indicator and has been shown to correlate to aqueous alteration in CM chondrites [7]. Shifts in this feature indicate BM.2022,M2-41 is more aqueously altered than BM.2022,M1-91. This is consistent with the determined mineralogy [1]. Bidirectional Reflectance Distribution Function (BRDF): The BRDF was measured for a powdered sample of the Winchcombe meteorite (BM.2022,M1-22) across 0 - 70° reflectance angles, in steps of 5°; at 15°, 30°, 45° and 60° incidence angles; and at 0°, 90° and 180° azimuthal angles. The dataset was then fitted using the Hapke BRDF model to enable constraints to be placed on the bulk scattering properties of the meteorite sample [8]. Importantly, the surface profile of the sample was characterized using an Alicona 3D® instrument. Therefore, two of the free parameters within the model - the filling factor, φ; and the RMS slope angle, θ - could be set, as φ = 0.65 ± 0.02 and θ = 16.11° (at 500 μm size-scale). This enabled w, b and hS to be set as the three open parameters within the Hapke BRDF model Least-Squares Levenberg-Marquardt fitting function. The best fit Hapke parameters were determined to be w = 0.152 ± 0.030, b = 0.633 ± 0.064 and hS = 0.016 ± 0.008. From the BRDF dataset, the broadband albedo value was calculated to be A = 4.09 ± 0.18 %, which can be converted to hemispheric albedo by multiplying by π [8]. As with the reflectance samples (previous section), modal mineralogy and water abundance were obtained for BM.2022,M1-22 [2]. Summary: VNIR and MIR spectroscopy are highly effective tools used in planetary remote sensing to determine the composition and physical properties of rocks and minerals. Here we are able to catalog several important spectral features and derived properties of the Winchcombe material for comparison to other meteorites and asteroids. The laboratory measured Winchcombe BRDF provides a reference photometric dataset for use in remote sensing studies of similar airless bodies, and by combining the IR spectra of the pristine Winchcombe material with other measurements on Earth, we can better understand and interpret data from Solar System objects and, in turn, learn more about their origins and evolution. [ABSTRACT FROM AUTHOR]

Nurses in service and academia joined to form the Nursing Resource Coalition in Southern California. The group works together to tackle common issues, such as shared resources, nursing's future, and measurement of vital indicators in both arenas.

Fractures about the shoulder in children rarely require operative treatment. Exceptions include open fractures and those associated with neurovascular compromise. Fractures of the proximal humerus in older children that cannot be adequately reduced and maintained should be treated with open reduction and internal fixation. Interposition of periosteum and biceps tendon can lead to difficulty in fracture reduction. Irreducible displaced fractures of the clavicular shaft, fractures that develop nonunion, and congenital pseudarthrosis of the clavicle can be treated by an intramedullary pin technique with bone grafting. Posterior displacement of fractures of the medical clavicle sometimes become an orthopedic emergency. Reduction by closed or open means should be accomplished to relieve compression of mediastinal structures. This injury does not require internal fixation. Types IV, V, and VI distal clavicle injuries require open reduction and reefing of the periosteal tube with occasional need for temporary lag-screw fixation. There is some debate about the type III injury. Large glenoid fractures involving the anterior rim that are associated with instability of the glenohumeral joint are best treated by open reduction and internal fixation.

In 16 adult dogs the anterior cruciate ligament (ACL) was transected and then reconstructed using freeze dried fascia lata allografts. Eight of the dogs had the intraarticular graft passed through drill holes in the tibia and femur, while in the other eight dogs the graft was passed through a drill hole in the tibia and routed "over-the-top" of the lateral femoral condyle. In all dogs the grafts were then passed deep to the lateral collateral ligament and secondarily secured to the tibia as an extraarticular reconstruction. Specimens from each group underwent histologic study and biomechanical testing on a mechanical testing system at 3, 6, 12, and 24 week intervals. All grafts were found to be intact at sacrifice with no overt evidence of biologic incompatibility. The knees displayed only mild instability to clinical testing without evidence of arthrosis. Histologically, the grafts appeared to function as a collagenous scaffolding for revascularization and fibrovascular creeping substitution. The mean maximum load at failure in the 24 week specimens reached 536.44 N, compared to values of 801.85 N in contralateral knees with an intact ACL.

Fractures and fracture dislocations of the forearm are common injuries that are being seen more frequently today in our active population. These injuries can occur in any sport, by direct blows to the arm or by falls on the outstretched hand. Many of these injuries are dramatic in their presentation and easily diagnosed, but only careful physical examination and radiographic evaluation avoids the pitfalls in diagnosis associated with the Monteggia's, Galeazzi's, and Essex-Lopresti's fracture dislocations. Most of these injuries require anatomic reduction to preserve the delicate interaction between radius and ulna in allowing forearm rotation. Owing to the instability of these fractures, open reduction and internal fixation is often required. Attention to detail in treatment and rehabilitation will avoid the problems of loss of motion, malunion, and nonunion associated with these injuries in the past.

Over a period of approximately 11 months, a total of 57 24 hour experiments was performed on 5 calves. The animals were fed a vitamin A-free diet and showed the common signs of vitamin A deficiency. During each experiment blood samples were taken hourly and the plasma iodoprotein content of each sample was determined. Each set of 24 values was subjected to Fourier analysis in an attempt to elucidate 24 hour, sinusoidal rhythms in iodoprotein concentration. A rhythm was deemed to be present where the chance of random sampling producing the observed pattern of concentration was less than or equal to 0.05. 25 such rhythms were detected. As the probability of random sampling giving rise to 25 rhythms in 57 tests is extremely small, circadian rhythms are assumed to exist in vitamin A-deficient, as in normal, calves. Rhythms, the characteristics of which are described here, were observed under natural conditions of day and night, and with controlled light and darkness. It is suggested that the occurrence of the rhythms, in relation to the environmental patterns of light and darkness, is better related to other aspects of brain activity than to those concerned with vision.

Amitraz has been shown to be successful in controlling mange and lice infestations on pigs which had failed to respond to diazinon and gamma-BHC, respectively, and by the use of a prophylactic programme to maintain pig herds mange free. In addition, trials have indicated the elimination of psoroptic mange from sheep by applying the compound to the animal using either conventional or less conventional methods of treatment. Mixed infections of Chorioptes spp., Psoroptes spp. and Sarcoptes spp., in cattle have also been controlled using spray applications of amitraz, where in some cases organochlorine, organophosphorus and organotin compounds had failed. In a pilot study a heavy infestation of chorioptic mange was controlled on a calf using a pour-on formulation of amitraz.