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Spontaneous intracranial hypotension (SIH) is caused by spinal cerebrospinal fluid (CSF) leaks, which result in continued loss of CSF volume and multiple debilitating clinical manifestations. The estimated annual incidence of SIH is 5/100,000. Diagnostic methods have evolved in recent years due to improved understanding of pathophysiology and implementation of advanced myelographic techniques. Here, we synthesize recent updates and contextualize them in an algorithm for diagnosis and treatment of SIH, highlighting basic principles and points of practice variability or continued debate. This discussion includes finer points of SIH diagnosis, CSF leak classification systems, less common types and variants of CSF leaks, brain MRI Bern scoring, potential SIH complications, key technical considerations, and positioning strategies for different types of dynamic myelography. The roles of conservative measures, non-targeted or targeted blood patches, surgery, and recently developed endovascular techniques are presented.

Aberrant internal carotid arteries (ICA) are congenital vascular anomalies that occur from involution of the cervical portion of the ICA, which leads to enlargement of the normally small collateral inferior tympanic and caroticotympanic arteries. The inferior tympanic artery is a branch of the external carotid artery, usually the ascending pharyngeal artery, which extends through the inferior tympanic canaliculus (ITC), a small foramen located along the cochlea promontory. Aberrant ICAs can also be associated with a persistent stapedial artery (PSA), which is an abnormal vessel that arises from the petrous ICA and passes through the obturator foramen of the stapes. An aberrant ICA is a very important anomaly to recognize on imaging. Accurately describing its presence is important to help prevent iatrogenic injury during intervention. It is also important to distinguish an aberrant ICA from a lateralized ICA. The improvement of spatial resolution with photon counting detector (PCD)-CT has been proven to provide higher performance in detection of sub-centimeter vascular lesions compared to conventional energy-integrated detector (EID)-CT. PCD-CT also provides superior visualization of small skull-based foramina such as the inferior tympanic canaliculus, which can aid in more accurately characterizing an aberrant ICA (variant course without ITC involvement).

We demonstrate the effectiveness of using hydrogen-doped argon as the support gas for the dielectric barrier discharge (DBD) ambient desorption/ionization (ADI) source in mass spectrometry. Also, we explore the chemistry responsible for the signal enhancement observed when using both hydrogen-doped argon and hydrogen-doped helium. The hydrogen-doped argon was tested for five analytes representing different classes of molecules. Addition of hydrogen to the argon plasma gas enhanced signals for gas-phase analytes and for analytes coated onto glass slides in positive and negative ion mode. The enhancements ranged from factors of 4 to 5 for gas-phase analytes and factors of 2 to 40 for coated slides. There was no significant increase in the background. The limit of detection for caffeine was lowered by a factor of 79 using H 2 /Ar and 2 using H 2 /He. Results are shown that help explain the fundamental differences between the pure-gas discharges and those that are hydrogen-doped for both argon and helium. Experiments with different discharge geometries and grounding schemes indicate that observed signal enhancements are strongly dependent on discharge configuration. Graphical Abstract ᅟ

Here, we report the most comprehensive characterization of nanodiamonds (NDs) yet undertaken. Five different samples from three different vendors were analyzed by a suite of analytical techniques, including X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), inductively coupled plasma mass spectrometry (ICP-MS), diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), Brunauer-Emmett-Teller (BET) surface area measurements, and particle size distribution (PSD) measurements. XPS revealed the elemental compositions of the ND surfaces (83–87 at.% carbon and 12–14 at.% oxygen) with varying amounts of nitrogen (0.4–1.8 at.%), silicon (0.1–0.7 at.%), and tungsten (0.3 at.% only in samples from one vendor). ToF-SIMS and ICP showed metal impurities (Al, Fe, Ni, Cr, etc. with unexpectedly high amounts of W in one vendor’s samples: ca. 900 ppm). Principal component analyses were performed on the ToF-SIMS and ICP data. DRIFT showed key functional groups (–OH, C=O, C–O, and C=C). BET showed surface areas of 50–214 m²/g. XRD and TEM revealed PSD (bimodal distribution and a wide PSD, 5–100 nm, for one vendor’s samples). XRD also provided particle sizes (2.7–27 nm) and showed the presence of graphite. EELS gave the sp²/sp³ contents of the materials (37–88 % sp³). PSD measurements were performed via differential sedimentation of the particles (mean particle size ca. 17–50 nm). This comprehensive understanding should allow for improved construction of nanodiamond-based materials. Graphical Abstract Five different nanodiamond samples were exhaustively characterized using a suite of analytical techniques.

We present mass spectrometric data demonstrating the effect that hydrogen has on a helium-based dielectric-barrier discharge (DBD) atmospheric-pressure plasma jet used as an ambient desorption/ionization (ADI) source. The addition of 0.9 % hydrogen to the helium support gas in a 35-W plasma jet increased signals for a range of test analytes, with enhancement factors of up to 68, without proportional increases in background levels. The changes in signal levels result from a combination of changes in the desorption kinetics from the surface and increased ion production in the gas phase. The enhancement in ADI-MS performance despite the quenching of key plasma species reported in earlier studies suggests that ionization with a H 2 /He plasma jet is the result of an alternate mechanism involving the direct generation of ionized hydrogen.

We have developed a multimodal ion source design that can be configured on the fly for various analysis modes, designed for more efficient and reproducible sampling at the mass spectrometer atmospheric pressure (AP) interface in a number of different applications. This vacuum-assisted plasma ionization (VaPI) source features interchangeable transmission mode and laser ablation sampling geometries. Operating in both AC and DC power regimes with similar results, the ion source was optimized for parameters including helium flow rate and gas temperature using transmission mode to analyze volatile standards and drug tablets. Using laser ablation, matrix effects were studied, and the source was used to monitor the products of model prebiotic synthetic reactions. Graphical Abstract ᅟ

This comprehensive study of the historical archaeology of the Caribbean provides sociopolitical context for the ongoing development of national identities. Long before the founding of Jamestown in 1607, there were Spanish forts, bustling towns, sugar plantations, and sea trade flourishing in the Caribbean. While richer nations, particularly the United States, may view the Caribbean today as merely a place for sun and fun, the island colonies were at one time far more important and lucrative to their European empire countries than their North American counterparts. From the 15th to the 19th centuries, as competing colonial powers vied with each other for military and economic advantage in the Western Hemisphere, events in the Caribbean directly influenced the American mainland. This is one rationale for the close study of historical archaeology in the Caribbean. Another is the growing recognition of how archaeological research can support the defining of national identities for the islands, many of them young independent states struggling to establish themselves economically and politically. By looking at cases in the French West Indies, specifically on Guadeloupe, in the Dutch Antilles and Aruba, in the British Bahamas, on Montserrat and St. Eustatius, on Barbados, and the within the U.S. Virgin Islands, the contributors to Island Lives have produced a broad overview of Caribbean historical archaeology. Island Lives makes clear that historical archaeology in the Caribbean will continue to grow and diversify due to the interest Caribbean peoples have in recording, preserving, and promoting their culture and heritage; the value it adds to their "heritage tourism"; and the connection it has to African American history and archaeology. In addition, the contributors point to the future by suggesting different trajectories that historical archaeology and its practitioners may take in the Caribbean arena. In so doing, they elucidate the problems and issues faced worldwide by researchers working in colonial and post-colonial societies. Paul Farnsworth is Associate Professor of Anthropology at Louisiana State University.

T2 coronal and axial magnetic resonance images (Figure 3) showed a heterogeneous T2 hyperintense left adrenal mass measuring 3 cm (yellow arrow), atypical for adrenal adenoma and suspicious for adrenocortical carcinoma DIAGNOSIS_ Testicular adrenal rest tumors and an adrenal nodule in a patient with congenital adrenal hyperplasia DISCUSSION_ Testicular adrenal rest tumors (TART) are benign tumors that occur secondary to longstanding stimulation of ectopic adrenal tissue within the testis of patients with CAH. CAH represents a group of genetic disorders involving the dysfunction of enzymes in the cortisol biosynthesis pathway.1 The impaired production of adrenal steroids leads to increased secretion of ACTH which, in turn, causes hyperplasia of the adrenal tissue. TART arise from the rete portion of the testis and are remnants of embryonic adrenal tissue that persist into adolescence.2,3 Coexisting adrenal adenomas, as in our patient, are seldom seen in these patients, although a review of the literature reveals that adrenal adenomas also occur due to longstanding inadequate hormone suppression in the setting of CAH.1,4'5'6'7 TART haves been reported in up to 94% of CAH patients; complications include mechanical obstruction, gonadal dysfunction, and infertility.3,5'4'7'8 Owing to the commonly asymptomatic nature of TART, diagnosis is usually not made until the tumors are large enough to be palpated or to cause mechanical obstruction.4,6,7 In patients with known CAH, TART are diagnosed earlier through routine screening, and ultrasound is considered the best, most cost-effective imaging modality for diagnosing TART.

Archaeologists working on plantation sites have typically ignored the role that violence played in the lives of enslaved African-Americans. By drawing together examples from archaeological publications in which violence has been mentioned, the commentary illustrates not only both the types and scale of violence endured by African-Americans, but also how archaeologists have effectively sanitized their publications on plantation life. In order to understand the African-American experience on the plantation, archaeologists must recognize that violence played a significant role in plantation society, and integrate it explicitly into all our models and interpretations of plantation life.

A team from Brigham Young University and I performed full-scale lateral load tests on individual and grouped 12.75x0.375 inch pipe piles spaced at varying distances behind an MSE wall. The individually loaded pile which acted as a control was spaced at 4.0 pile diameters from the wall face, and the three grouped piles which were loaded in unison were spaced at 3.0, 2.8, and 1.8 pile diameters from the wall face and transversely spaced at 4.7 pile diameters center-to-center. The purpose of these tests was to determine the extent of group effects on lateral pile resistance, induced loads in soil reinforcements, and MSE wall panel deflections compared to those previously observed in individually laterally loaded piles behind MSE walls. The computer model LPILE was used in my analysis of the measured test data. The p-multipliers back-calculated with LPILE for the grouped piles were 0.25, 0.60, and 0.25 for the grouped piles spaced at 3.0, 2.8, and 1.8 pile diameters from the wall, respectively. These values are lower than that predicted for piles at the same pile-to-wall spacings using the most recent equation for computing p-multipliers. I propose the use of an additional p-multiplier for grouped piles near an MSE wall, a group-effect p-multiplier, to account for discrepancies between individual and grouped pile behaviors. The group effect p-multipliers were 0.35, 0.91, and 0.74 for the grouped piles spaced at 3.0, 2.8, and 1.8 pile diameters from the wall, respectively. The average group-effect p-multiplier was 0.66. Additionally, I used LPILE to analyze test data from Pierson et al. (2009), who had previously performed full-scale lateral load tests of individual and grouped shafts. In said analysis, the group of three 3-foot diameter concrete shafts spaced at 2.0 shaft diameters from the wall face and transversely spaced at 5.0 shaft diameters center-to-center had an average group effect p-multiplier of 0.78. As in previous studies, the induced forces in soil reinforcements in this study were greatest either near the locations of the test piles or at the MSE wall face. The most recent equation for calculating the maximum induced force in a soil reinforcement strip was reasonably effective in predicting the measured maximum loads when superimposed between the test piles, with 65% and 85% of the data points falling within the one and two standard deviation boundaries, respectively, of the original data used to develop the equation. Deflection of the MSE wall panels was greater during the grouped pile test than was previously observed for individually loaded piles under similar pile head deflections--with a maximum wall deflection of 0.31 inch compared to the previous average of 0.10 inch for pile head deflections of about 1.25 inches.