Radiocarbon signatures of carbon phases exported by Swiss rivers in the Anthropocene.

Lateral carbon transport through the land-to-ocean-aquatic-continuum (LOAC) represents a key component of the global carbon cycle. This LOAC involves complex processes, many of which are prone to anthropogenic perturbation, yet the influence of natural and human-induced drivers remains poorly constrained. This study examines the radiocarbon (C) signatures of particulate and dissolved organic carbon (POC, DOC) and dissolved inorganic carbon (DIC) transported by Swiss rivers to assess controls on sources and cycling of carbon within their watersheds.

Associations of Community and Individual Social Determinants of Health With Medication Adherence in Patients With Atrial Fibrillation: A Retrospective Cohort Study.

Background Despite guideline-recommended use of oral anticoagulation (OAC) for stroke prevention in atrial fibrillation (AF), OAC medication adherence among patients with AF in the United States ranges from 47% to 82%. To characterize potential causes of nonadherence, we analyzed associations between community and individual social risk factors and OAC adherence for stroke prevention in AF. Methods and Results A retrospective cohort analysis of patients with AF was conducted using the IQVIA PharMetrics Plus claims data from January 2016 to June 2020, and 3-digit ZIP code-level social risk scores were calculated using American Community Survey and commercial data.

Residence times of groundwater along a flow path in the Great Artesian Basin determined by Kr, Cl and He: Implications for palaeo hydrogeology.

Understanding the age distribution of groundwater can provide information on both the recharge history as well as the geochemical evolution of groundwater flow systems. Of the few candidates available that can be used to date old groundwater, Kr shows the most promise because its input function is constant through time and there are less sources and sinks to complicate the dating procedure in comparison to traditional tracers such as Cl and He. In this paper we use Kr in a large groundwater basin to obtain a better understanding of the residence time distribution of an unconfined-confined aquifer system.

Nearshore Zone Dynamics Determine Pathway of Organic Carbon From Eroding Permafrost Coasts.

Collapse of permafrost coasts delivers large quantities of particulate organic carbon (POC) to Arctic coastal areas. With rapidly changing environmental conditions, sediment and organic carbon (OC) mobilization and transport pathways are also changing. Here, we assess the sources and sinks of POC in the highly dynamic nearshore zone of Herschel Island-Qikiqtaruk (Yukon, Canada).

Particulate Organic Matter Dynamics in a Permafrost Headwater Stream and the Kolyma River Mainstem.

Ongoing rapid arctic warming leads to extensive permafrost thaw, which in turn increases the hydrologic connectivity of the landscape by opening up subsurface flow paths. Suspended particulate organic matter (POM) has proven useful to trace permafrost thaw signals in arctic rivers, which may experience higher organic matter loads in the future due to expansion and increasing intensity of thaw processes such as thermokarst and river bank erosion. Here we focus on the Kolyma River watershed in Northeast Siberia, the world's largest watershed entirely underlain by continuous permafrost.

Optimization of capture-recapture monitoring of elusive species illustrated with a threatened grasshopper.

Information on population sizes and trends of threatened species is essential for their conservation, but obtaining reliable estimates can be challenging. We devised a method to improve the precision of estimates of population size obtained from capture-recapture studies for species with low capture and recapture probabilities and short seasonal activity, illustrated with population data of an elusive grasshopper (Prionotropis rhodanica). We used data from 5 capture-recapture studies to identify methodological and environmental factors affecting capture and recapture probabilities and estimates of population size.

Rivers across the Siberian Arctic unearth the patterns of carbon release from thawing permafrost.

Climate warming is expected to mobilize northern permafrost and peat organic carbon (PP-C), yet magnitudes and system specifics of even current releases are poorly constrained. While part of the PP-C will degrade at point of thaw to CO and CH to directly amplify global warming, another part will enter the fluvial network, potentially providing a window to observe large-scale PP-C remobilization patterns. Here, we employ a decade-long, high-temporal resolution record of C in dissolved and particulate organic carbon (DOC and POC, respectively) to deconvolute PP-C release in the large drainage basins of rivers across Siberia: Ob, Yenisey, Lena, and Kolyma.

Quantifying Degradative Loss of Terrigenous Organic Carbon in Surface Sediments Across the Laptev and East Siberian Sea.

Ongoing permafrost thaw in the Arctic may remobilize large amounts of old organic matter. Upon transport to the Siberian shelf seas, this material may be degraded and released to the atmosphere, exported off-shelf, or buried in the sediments. While our understanding of the fate of permafrost-derived organic matter in shelf waters is improving, poor constraints remain regarding degradation in sediments.

Remobilization of Old Permafrost Carbon to Chukchi Sea Sediments During the End of the Last Deglaciation.

Climate warming is expected to destabilize permafrost carbon (PF-C) by thaw-erosion and deepening of the seasonally thawed active layer and thereby promote PF-C mineralization to CO and CH. A similar PF-C remobilization might have contributed to the increase in atmospheric CO during deglacial warming after the last glacial maximum. Using carbon isotopes and terrestrial biomarkers (ΔC, δC, and lignin phenols), this study quantifies deposition of terrestrial carbon originating from permafrost in sediments from the Chukchi Sea (core SWERUS-L2-4-PC1).

Bounding cross-shelf transport time and degradation in Siberian-Arctic land-ocean carbon transfer.

The burial of terrestrial organic carbon (terrOC) in marine sediments contributes to the regulation of atmospheric CO on geological timescales and may mitigate positive feedback to present-day climate warming. However, the fate of terrOC in marine settings is debated, with uncertainties regarding its degradation during transport. Here, we employ compound-specific radiocarbon analyses of terrestrial biomarkers to determine cross-shelf transport times.

A preliminary phylogeny of the South African Lentulidae.

Background: The grasshopper family Lentulidae is endemic to eastern and southern Africa, with its center of diversity situated in South Africa, the highest diversity being found in the Cape Floristic Region, which is one of the global biodiversity hotspots. The family consists of 35 genera sorted in two subfamilies. This study provides first insights into the phylogeny of Lentulidae.

[Are we sectioning the cochlear efferent system during vestibular neurotomy?].

Introduction: In addition to sensory neurons which transmit information from the inner ear to the brain, there is a system of efferent feedback fibers, called the olivocochlear system, carrying signals from the brain to the ear. Over the past half-century, the efferent system has been extensively studied in animals and results provided theories as to the functional significance of these efferents: to improve signal-to-noise ratio in the auditory periphery, to mediate selective attention, and to protect the inner ear from acoustic overexposure. The results of several studies conducted in man rely on the study of patients who have undergone a vestibular neurectomy.

[Our current results with acoustic neurinoma surgery].

Out of 130 CPA tumors operated on between 1993 and 1997, 91 were vestibular schwannomas less than 25 mm with preoperative hearing and normal facial function. The pre and postoperative facial and hearing functions were analyzed prospectively. The surgical technique applied was the complete tumor removal via retrosigmoid approach under facial nerve monitoring and CPA endoscopy.

Apoptosis mediates cell death following traumatic injury in rat hippocampal neurons.

A model of in vitro traumatic injury with dissociated rat hippocampal neurons was studied to explore the mechanism of cell death. The neurotoxicity induced by traumatic injury to the cell culture can be transferred to a naive uninjured culture by media exchange. This toxicity is attenuated by dimethylsulfoxide or superoxide dismutase, suggesting that this toxicity is mediated by a free radical generation.

Trauma-induced neurotoxicity in rat hippocampal neurons.

Background And Purpose: We have previously shown that traumatic injury of hippocampal cells triggers release of a soluble neurotoxin that can be transferred to an uninjured culture. The mechanism of this trauma-induced neurotoxicity is independent of glutamate receptor activation. We extended this observation to study the mechanism of this neurotoxicity.

A randomized clinical trial in bronchogenic small-cell carcinoma evaluating alternating maintenance therapy of vincristine, adriamycin, procarbazine, and etoposide (VAPE) with cyclophosphamide, CCNU, and methotrexate (CCM) versus CCM maintenance alone in complete responders following VAPE induction and late intensification.

Initially, 109 evaluable patients with locally advanced or metastatic small cell lung cancer (SCLC) were treated with vincristine, Adriamycin, procarbazine, and etoposide (VAPE). Partial (PR) or nonresponders (NR) were crossed to CCM (cyclophosphamide, CCNU, and methotrexate) and then to HMiVe (hexamethylmelamine, mitomycin C, vinblastine) sequentially at maximum response. Complete responders (CR) were intensified by 50% with VAPE primarily and randomized to VAPE, alternating with CCM or CCM alone during maintenance.

Differential changes in central monoaminergic metabolism during first and multiple sodium depletions in rats.

To investigate the role of central monoamines in the behavior of sodium appetite, serotonergic and dopaminergic metabolism in regions of the forebrain and dorsal hindbrain were measured in sodium-depleted rats. Male Sprague-Dawley rats were sodium depleted by injection of the diuretic-natriuretic drug, Lasix (furosemide, 10 mg), and maintained on a sodium-deficient diet overnight. Rats were tested at a first sodium depletion or after multiple sodium depletions.

A phase II clinical trial evaluating the use of two sequential, four-drug combination chemotherapy regimens in ambulatory bronchogenic adenocarcinoma patients.

Forty-three ambulatory patients with locally advanced or metastatic bronchogenic adenocarcinoma were sequentially treated with two potentially mutually non-cross-resistant chemotherapy regimens. A new regimen, MVPF (mitomycin-c, vinblastine, procarbazine, and 5-fluorouracil), was given until progressive disease occurred. Then, a second regimen--MOCC (methotrexate, vincristine [Oncovin], cyclophosphamide, and CCNU)--was initiated.

Lobular carcinoma of the breast metastatic to bone with unusual clinical, radiologic, and pathologic features mimicking osteopoikilosis.

A 55-year-old woman who underwent a right radical mastectomy for infiltrating lobular carcinoma was found to have multiple diffuse osteoblastic bone lesions. Since she was asymptomatic, had no elevation of alkaline phosphatase, and the lesions did not take up technetium pyrophosphate on bone scan, she was thought to have osteopoikilosis. An iliac bone biopsy was performed that showed greatly thickened bony trabeculae with diffuse delicate marrow fibrosis entrapping easily overlooked short strands of small malignant cells.

Cisplatin-induced autonomic neuropathy.

A 57-year-old man with bronchogenic squamous cell carcinoma developed an autonomic neuropathy following treatment with a chemotherapy combination which included cisplatin. The autonomic neuropathy resolved following discontinuation of the cisplatin and treatment with dextroamphetamine. The following case represents a patient with bronchogenic carcinoma treated with cyclophosphamide, doxorubicin, and cisplatin, who developed a severe autonomic neuropathy following chemotherapy administration.

A controlled clinical trial testing two potentially non-cross-resistant chemotherapeutic regimens in small-cell carcinoma of the lung.

With the objectives of improving response rate, duration of response, and survival in small-cell carcinoma of the lung, 39 patients were randomized to remission-induction with either one of two potentially non-cross-resistant drug combinations: APE (consisting of adriamycin, 35 mg/m2 IV, D1 Q 3 weeks; procarbazine, 60 mg/m2 PO, D1-10 Q 3 weeks; and the epipodophyllotoxin (VP16-213), 130 mg/m2 IV, D8, 15 Q 3 weeks) or MOCC (composed of methotrexate, 15 mg/m2 IV (with [vincristine] Oncovin) or PO twice weekly D8-21 Q 3 weeks; Oncovin, 1.5 mg/m2 IV, D8, 15 Q 3 weeks; cyclophosphamide, 600 mg/m2 IV, D1 Q 3 weeks, and CCNU, 60 mg/m2 PO Q 6 weeks). A fixed crossover to the alternate regimen occurred at three months.

Calcitonin as a marker for bronchogenic cancer: a prospective study.

A prospective study was done of serum calcitonin (HCT) levels in 61 patients with bronchogenic cancer. Initially, 52% of patients had hypercalcitonemia. Hypercalcitonemia was not confined to patients with any particular histologic type.