544 research outputs found

    Puma predation on radiocollared and uncollared bighorn sheep

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    BackgroundWe used Global Positioning System (GPS) data from radiocollared pumas (Puma concolor) to identify kill sites of pumas preying upon an endangered population of bighorn sheep (Ovis canadensis) in southern California. Our aims were to test whether or not pumas selected radiocollared versus uncollared bighorn sheep, and to identify patterns of movement before, during, and after kills.FindingsThree pumas killed 23 bighorn sheep over the course of the study, but they did not preferentially prey on marked (radiocollared) versus unmarked bighorn sheep. Predation occurred primarily during crepuscular and nighttime hours, and 22 kill sites were identified by the occurrence of 2 or more consecutive puma GPS locations (a cluster) within 200 m of each other at 1900, 0000, and 0600 h.ConclusionWe tested the "conspicuous individual hypothesis" and found that there was no difference in puma predation upon radiocollared and uncollared bighorn sheep. Pumas tended to move long distances before and after kills, but their movement patterns immediately post-kill were much more restricted. Researchers can exploit this behaviour to identify puma kill sites and investigate prey selection by designing studies that detect puma locations that are spatially clustered between dusk and dawn

    A Note on the Integral Formulation of Einstein's Equations Induced on a Braneworld

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    We revisit the integral formulation (or Green's function approach) of Einstein's equations in the context of braneworlds. The integral formulation has been proposed independently by several authors in the past, based on the assumption that it is possible to give a reinterpretation of the local metric field in curved spacetimes as an integral expression involving sources and boundary conditions. This allows one to separate source-generated and source-free contributions to the metric field. As a consequence, an exact meaning to Mach's Principle can be achieved in the sense that only source-generated (matter fields) contributions to the metric are allowed for; universes which do not obey this condition would be non-Machian. In this paper, we revisit this idea concentrating on a Randall-Sundrum-type model with a non-trivial cosmology on the brane. We argue that the role of the surface term (the source-free contribution) in the braneworld scenario may be quite subtler than in the 4D formulation. This may pose, for instance, an interesting issue to the cosmological constant problem.Comment: 10 pages, no figures, accepted for publication in the General Relativity and Gravitation Journa

    The Shaken Baby Syndrome: A Clinical, Pathological, and Biomechanical Study

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    Because a history of shaking is often lacking in the so-called “shaken baby syndrome,” diagnosis is usually based on a constellation of clinical and radiographic findings. Forty-eight cases of infants and young children with this diagnosis seen between 1978 and 1985 at the Children\u27s Hospital of Philadelphia were reviewed. All patients had a presenting history thought to be suspicious for child abuse, and either retinal hemorrhages with subdural or subarachnoid hemorrhages or a computerized tomography scan showing subdural or subarachnoid hemorrhages with interhemispheric blood. The physical examination and presence of associated trauma were analyzed; autopsy findings for the 13 fatalities were reviewed. All fatal cases had signs of blunt impact to the head, although in more than half of them these findings were noted only at autopsy. All deaths were associated with uncontrollably increased intracranial pressure. Models of 1-month-old infants with various neck and skull parameters were instrumented with accelerometers and shaken and impacted against padded or unpadded surfaces. Angular accelerations for shakes were smaller than those for impacts by a factor of 50. All shakes fell below injury thresholds established for subhuman primates scaled for the same brain mass, while impacts spanned concussion, subdural hematoma, and diffuse axonal injury ranges. It was concluded that severe head injuries commonly diagnosed as shaking injuries require impact to occur and that shaking alone in an otherwise normal baby is unlikely to cause the shaken baby syndrome

    Loss of Trop2 causes ErbB3 activation through a neuregulin-1-dependent mechanism in the mesenchymal subtype of HNSCC

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    In head and neck squamous cell cancer (HNSCC), four intrinsic subtypes (or groups) have been identified, and each one possesses a unique biology that will require specific treatment strategies. We previously reported that mesenchymal (group 2) tumors exhibit reduced levels of Trop2 expression. In this study, we investigated the functional role of Trop2 in HNSCC and find that loss results in autocrine activation of the EGFR family member ErbB3 via neuregulin-1. Trop2 localizes to both the cell surface and cytosol of HNSCC cells and forms a complex with neuregulin-1, which is predominantly cytosolic. Inactivation of Trop2 increases the concentration of neuregulin-1 at the cell surface where it is cleaved to activate ErbB3. In primary HNSCC, detection of ErbB3 activation was limited to Trop2 negative tumors. An analysis of the Cancer Genome Atlas (TCGA) HNSCC dataset confirms enrichment for ErbB3 activity in mesenchymal tumors. Notably, Trop2 loss triggers sensitivity to anti-ErbB3 antibodies, which results in reduced proliferation and tumorigenic growth of Trop2 negative HNSCC cancer cells. These results uncover a molecular mechanism by which tumor cells control the amount of cell-surface neuregulin-1 available for cleavage and ErbB3 activation. Moreover, we demonstrate that Trop2 is a potential surrogate biomarker to identify tumors with ErbB3 activation and may therefore respond to anti-ErbB3 therapeutics

    Pharmacists in Pharmacovigilance: Can Increased Diagnostic Opportunity in Community Settings Translate to Better Vigilance?

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    The pharmacy profession has undergone substantial change over the last two to three decades. Whilst medicine supply still remains a central function, pharmacist’s roles and responsibilities have become more clinic and patient focused. In the community (primary care), pharmacists have become important providers of healthcare as Western healthcare policy advocates patient self-care. This has resulted in pharmacists taking on greater responsibility in managing minor illness and the delivery of public health interventions. These roles require pharmacists to more fully use their clinical skills, and often involve diagnosis and therapeutic management. Community pharmacists are now, more than ever before, in a position to identify, record and report medication safety incidents. However, current research suggests that diagnostic ability of community pharmacists is questionable and they infrequently report to local or national schemes. The aim of this paper is to highlight current practice and suggest ways in which community pharmacy can more fully contribute to patient safety

    Mycobacterium intermedium Granulomatous Dermatitis from Hot Tub Exposure

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    Nontuberculous mycobacteria, which are widespread in the environment, frequently cause opportunistic infections in immunocompromised patients. We report the first case of a patient with chronic granulomatous dermatitis caused by a rarely described organism, Mycobacterium intermedium. The infection was associated with exposure in a home hot tub

    Penerapan Metode Eksperimen untuk Meningkatkan Konsep Dasar Sains pada Anak Didik Kelompok A Tk Pkk Suruhwadang Kecamatan Kademangan Kabupaten Blitar

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    Tujuan penelitian ini adalah untuk memperoleh tentang kemampuan kognitif anak dalamhal konsep dasar sains dengan menggunakan metode eksperimen pada anak didik kelompokA TK PKK Suruhwadang sebelum dan sesudah dilakukan tindakan. Melakukan tindakanberupa penerapan metode eksperimen untuk meningkatkan kemampuan kognitif dalamkonsep dasar sains pada anak didik kelompok A TK PKK Suruhwadang. Mengetahui adatidaknya perbedaan kemampuan konsep dasar sains dengan menggunakan metodeeksperimen pada anak didik kelompok A TK PKK Suruhwadang antara sebelum dan setelahdilakukan tindakan. Rumusan masalah pada penitilian ini adalah apakah metode eksperimendapat meningkatkan kemampuan pemahaman konsep dasar sains pada anak didik kelompokA TK PKK Suruhwadang Kecamatan Kademangan Kabupaten Blitar. Untuk menjawabrumusan masalah digunakan jenis penelitian tindakan kelas (PTK) dengan model Kemmisdan Taggart melalui empat tahapan yaitu tahap perencanaan , pelaksanaan, observasi danrefleksiyang dilalui dengan dua siklus. Teknik pengumpulan data menggunakan teknikobservasi dan dokumentasi. Adapun instrumen yang digunakan adalah lembar observasikegiatan anak dan lembar observasi pembelajaran oleh guru.Hasil penelitian menunjukanbahwa kemampuan kognitif anak kelompok A pada konsep dasar sain pada pra penelitianmenunjukkan prosentase 56.25%. Setelah pelaksanaan siklus I tentang bidang kemampuankognitif pada konsep dasar sains menunjukkan 59% mengalami peningkatan .Setelahpelaksanaan siklus ke II naik menjadi 83%. Hal ini menunjukkan pelaksanaan siklus ke IItelah mencapai kriteria ketuntasan dan membuktikan bahwa dengan metode eksperimendapat meningkatkan kemampuan kognitif dalam konsep dasar sains
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