Anthropogenic uranium signatures in turtles, tortoises, and sea turtles from nuclear sites.

Chelonians (turtles, tortoises, and sea turtles) grow scute keratin in sequential layers over time. Once formed, scute keratin acts as an inert reservoir of environmental information. For chelonians inhabiting areas with legacy or modern nuclear activities, their scute has the potential to act as a time-stamped record of radionuclide contamination in the environment.

Separation of protactinium from uranium-niobium alloys for Pa-U radiochronometry in nuclear forensic investigations.

Unlabelled: The isolation and purification of protactinium from uranium materials is essential for Pa-U radiochronometry, but separating Pa from uranium-niobium alloys, a common material in the nuclear fuel cycle, is challenging due to the chemical similarity of Pa and Nb. Here we present three resin chromatography separation techniques for isolating Pa from U and Nb which were independently developed by three different laboratories through ad hoc adaptations of standard operating procedures. Our results underscore the need for and value of purification methods suitable for a diversity of uranium-based materials to ensure the operational readiness of nuclear forensics laboratories.

Trace Actinide Signatures of a Bulk Neptunium Sample.

In nuclear forensic analyses, measurements of actinide elements in a sample can assist with identifying interdicted or unknown materials. While these radiochemical signatures have been extensively investigated in uranium materials, less is known about bulk neptunium samples. This paper describes the measurement of trace actinide concentrations and isotopic profiles in a Np oxide sample.

Dural Venous Sinus Stent Placement Reduces Dosage Requirements for Carbonic Anhydrase Inhibitors in Patients with Idiopathic Intracranial Hypertension.

This retrospective single-center study evaluated the change in required dosage of acetazolamide and topiramate before and after dural venous sinus stent placement (VSSP) for idiopathic intracranial hypertension (IIH). Adults diagnosed with IIH who failed optimized medical management and were treated with VSSP were included. This study comprised 55 patients who underwent VSSP for the diagnosis of IIH.

Nuclear Sample Provenance and Age Determination Using Ruthenium Isotopes.

Measurements of the ruthenium isotopic composition of nuclear samples could provide information about the method of sample production, sample irradiation history, and age. To investigate the feasibility and applicability of this idea, this study focuses on measurements of the ruthenium isotope composition of a nominally single-isotope Ru radioactivity standard, where the complications of environmental mixing are eliminated. The measurements of the Ru standards reveal unusual stable ruthenium isotopic compositions consistent with fissiogenic ruthenium.

Trace element geochemistry of coarse-grained angrites from Northwest Africa: Implications for their petrogenesis on the angrite parent body.

The angrites are a class of achondrites that encompass a wide range of igneous textures from quenched, volcanic, and subvolcanic stones to slowly cooled, plutonic rocks. The compositions of the various geochemical reservoirs generating this variety of rocks have not been investigated fully because historically the numbers and masses of angrites available for study have been quite small. However, the rapid increase in meteorites from Northwest Africa (NWA) has enabled a renewed opportunity for such an investigation.

The impact and recovery of asteroid 2018 LA.

The June 2, 2018, impact of asteroid 2018 LA over Botswana is only the second asteroid detected in space prior to impacting over land. Here, we report on the successful recovery of meteorites. Additional astrometric data refine the approach orbit and define the spin period and shape of the asteroid.

Chromium Isotopic Evidence for Mixing of NC and CC Reservoirs in Polymict Ureilites: Implications for Dynamical Models of the Early Solar System.

Nucleosynthetic isotope anomalies show that the first few million years of solar system history were characterized by two distinct cosmochemical reservoirs, CC (carbonaceous chondrites and related differentiated meteorites) and NC (the terrestrial planets and all other groups of chondrites and differentiated meteorites), widely interpreted to correspond to the outer and inner solar system, respectively. At some point, however, bulk CC and NC materials became mixed, and several dynamical models offer explanations for how and when this occurred. We use xenoliths of CC materials in polymict ureilite (NC) breccias to test the applicability of such models.

The fall, recovery, classification, and initial characterization of the Hamburg, Michigan H4 chondrite.

The Hamburg meteorite fell on January 16, 2018, near Hamburg, Michigan, after a fireball event widely observed in the U.S. Midwest and in Ontario, Canada.

Circulating tumor cell analysis in locally advanced and metastatic squamous cell carcinoma of the head and neck.

Background: Circulating tumors cells (CTCs) are considered an early step towards metastasis and have been linked to poor prognosis in several types of cancer. CTCs in squamous cell carcinoma of the head and neck (SCCHN) have an unclear role.

Methods: In this prospective study, patients with locally advanced or metastatic SCCHN had CTC counts assessed before starting systemic treatment using the CellSearch System.

Chondrules reveal large-scale outward transport of inner Solar System materials in the protoplanetary disk.

Dynamic models of the protoplanetary disk indicate there should be large-scale material transport in and out of the inner Solar System, but direct evidence for such transport is scarce. Here we show that the εTi-εCr-ΔO systematics of large individual chondrules, which typically formed 2 to 3 My after the formation of the first solids in the Solar System, indicate certain meteorites (CV and CK chondrites) that formed in the outer Solar System accreted an assortment of both inner and outer Solar System materials, as well as material previously unidentified through the analysis of bulk meteorites. Mixing with primordial refractory components reveals a "missing reservoir" that bridges the gap between inner and outer Solar System materials.

A Randomized Phase 2 Study of Pembrolizumab With or Without Radiation in Patients With Recurrent or Metastatic Adenoid Cystic Carcinoma.

Purpose: We evaluated the safety and efficacy of pembrolizumab (pembro) ± radiation therapy (RT) in a phase 2 study among patients with progressive, metastatic adenoid cystic carcinoma (ACC).

Methods And Materials: Eligible patients had metastatic ACC with progression within the last year and ≥1 measurable lesion. Patients were randomized to pembro alone or with RT to 30 Gy in 5 fractions (pembroRT).

The origin of the unique achondrite Northwest Africa 6704: Constraints from petrology, chemistry and Re-Os, O and Ti isotope systematics.

Northwest Africa (NWA) 6704 is a unique achondrite characterized by a near-chondritic major element composition with a remarkably intact igneous texture. To investigate the origin of this unique achondrite, we have conducted a combined petrologic, chemical, and Re-Os, O, and Ti isotopic study. The meteorite consists of orthopyroxene megacrysts (EnWoFs; Fe/Mn = 1.

Petrogenesis and Provenance of Ungrouped Achondrite Northwest Africa 7325 from Petrology, Trace Elements, Oxygen, Chromium and Titanium Isotopes, and Mid-IR Spectroscopy.

Northwest Africa (NWA) 7325 is an ungrouped achondrite that has recently been recognized as a sample of ancient differentiated crust from either Mercury or a previously unknown asteroid. In this work we augment data from previous investigations on petrography and mineral compositions, mid-IR spectroscopy, and oxygen isotope compositions of NWA 7325, and add constraints from Cr and Ti isotope compositions on the provenance of its parent body. In addition, we identify and discuss notable similarities between NWA 7325 and clasts of a rare xenolithic lithology found in polymict ureilites.

Trends in Resident Operative Teaching Opportunities for Treatment of Intracranial Aneurysms.

Objective: The International Subarachnoid Aneurysm Trial heralded a paradigm shift in the treatment of intracranial aneurysms. During this same time frame, neurosurgical training programs increased in size and scope. The present study examines the impact of trends in surgical clipping and the endovascular treatment of intracranial aneurysms, over one decade, and the neurosurgical resident complement on the resident teaching environment using the Nationwide Inpatient Sample (NIS).

Parent vessel occlusion for treatment of cerebral aneurysms: Is there still an indication? A series of 17 patients.

Introduction/purpose: Flow diversion has allowed cerebrovascular neurosurgeons and neurointerventionalists to treat complex, large aneurysms, previously treated with trapping, bypass, and/or parent vessel sacrifice. However, a minority of aneurysms remain that cannot be treated endovascularly, and microsurgical treatment is too dangerous. However, balloon test occlusion (macro and micro), micro WADA testing, ICG, intra-angiography and intra-operative monitoring are all available to clinically test the hypothesis that vessel sacrifice is safe.

Decompressive craniectomy for severe traumatic brain injury: clinical study, literature review and meta-analysis.

Objective: To examine the clinical and neurological outcome of patients who sustained a severe non-penetrating traumatic brain injury (TBI) and underwent unilateral decompressive craniectomy (DC) for refractory intracranial hypertension.

Design: Single center, retrospective, observational.

Setting: Level I Trauma Center in Portland, Maine.

Re-treatment rates after treatment with the Pipeline Embolization Device alone versus Pipeline and coil embolization of cerebral aneurysms: a single-center experience.

OBJECT The optimal strategy for use of the Pipeline Embolization Device (PED, ev3 Neurovascular) has not been clearly defined. The authors examined re-treatment rates after treatment with PED alone versus PED and adjunctive coil embolization (PED/coil). METHODS The authors retrospectively examined cerebral aneurysms treated with the PED from May 2011 to March 2014.

Microparticles Impair Hypotensive Cerebrovasodilation and Cause Hippocampal Neuronal Cell Injury after Traumatic Brain Injury.

Endothelin-1 (ET-1), tissue plasminogen activator (tPA), and extracellular signal-regulated kinases-mitogen activated protein kinase (ERK-MAPK) are mediators of impaired cerebral hemodynamics after fluid percussion brain injury (FPI) in piglets. Microparticles (MPs) are released into the circulation from a variety of cells during stress, are pro-thrombotic and pro-inflammatory, and may be lysed with polyethylene glycol telomere B (PEG-TB). We hypothesized that MPs released after traumatic brain injury impair hypotensive cerebrovasodilation and that PEG-TB protects the vascular response via MP lysis, and we investigated the relationship between MPs, tPA, ET-1, and ERK-MAPK in that process.

Endoscopic approaches to brainstem cavernous malformations: Case series and review of the literature.

Background: Symptomatic cavernous malformations involving the brainstem are frequently difficult to access via traditional methods. Conventional skull-base approaches require significant brain retraction or bone removal to provide an adequate operative corridor. While there has been a trend toward limited employment of the most invasive surgical approaches, recent advances in endoscopic technology may complement existing methods to access these difficult to reach areas.

Cerebral hemodynamics at altitude: effects of hyperventilation and acclimatization on cerebral blood flow and oxygenation.

Objective: Alterations in cerebral blood flow (CBF) and cerebral oxygenation are implicated in altitude-associated diseases. We assessed the dynamic changes in CBF and peripheral and cerebral oxygenation engendered by ascent to altitude with partial acclimatization and hyperventilation using a combination of near-infrared spectroscopy, transcranial Doppler ultrasound, and diffuse correlation spectroscopy.

Methods: Peripheral (Spo2) and cerebral (Scto2) oxygenation, end-tidal carbon dioxide (ETCO2), and cerebral hemodynamics were studied in 12 subjects using transcranial Doppler and diffuse correlation spectroscopy (DCS) at 75 m and then 2 days and 7 days after ascending to 4559 m above sea level.

Elderly patients with intracranial aneurysms have higher quality of life after coil embolization: a decision analysis.

Objective: To develop a decision analytic model to calculate outcomes after treatment of cerebral aneurysms in elderly patients. Neurosurgical clipping and endovascular coiling for both ruptured and unruptured aneurysms were compared with predicted health-related quality of life (HRQoL) after treatment.

Methods: A Medline search of articles published in English between 1995 and June 2012 was performed using key words: 'intracranial aneurysms', 'treatment', or various combinations of 'elderly', 'older', or 'decade'.

Endovascular approaches to pial arteriovenous malformations.

Endovascular approaches to arteriovenous malformations (AVMs) are often necessary to define and help treat these often complex lesions. Angiography provides important information to help plan surgical or radiosurgical approaches. Modern embolization techniques allow AVMs to be treated with the goals of making surgery safer and easier, eliminating high-risk features in patients with AVMs who are otherwise not candidates for treatment, and even potentially curing the patient of the lesion.

Critical assessment of complications associated with use of the Pipeline Embolization Device.

Background: The Pipeline Embolization Device (PED) has become an important tool in the treatment of complex cerebrovascular pathology since it was approved by the Food and Drug Administration in April 2011.

Objective: To determine the overall complication rate (permanent and transient) associated with the use of this new device from a single institution.

Methods: We retrospectively examined a prospectively maintained database of our patients treated with the PED since its availability to the current time.