Understanding the relationship between a dam's size and its ecological effects is important for prioritization of river restoration efforts based on dam removal. Although much is known about the effects of large storage dams, this information may not be applicable to small dams, which represent the vast majority of dams being considered for removal. To better understand how dam effects vary with size, we conducted a multidisciplinary study of the downstream effect of dams on a range of ecological characteristics including geomorphology, water chemistry, periphyton, riparian vegetation, benthic macroinvertebrates, and fish.
View Article and Find Full Text PDFJ Am Water Resour Assoc
April 2019
Downstream flow in rivers is repeatedly delayed by hydrologic exchange with off-channel storage zones where biogeochemical processing occurs. We present a dimensionless metric that quantifies river connectivity as the balance between downstream flow and the exchange of water with the bed, banks, and floodplains. The degree of connectivity directly influences downstream water quality - too little connectivity limits the amount of river water exchanged and leads to biogeochemically inactive water storage, while too much connectivity limits the contact time with sediments for reactions to proceed.
View Article and Find Full Text PDFPurpose: This study aims (1) to investigate the feasibility of robot-assisted penetrating keratoplasty (PK) using the new Da Vinci Xi Surgical System and (2) to report what we believe to be the first use of this system in experimental eye surgery.
Methods: Robot-assisted PK procedures were performed on human corneal transplants using the Da Vinci Xi Surgical System. After an 8-mm corneal trephination, four interrupted sutures and one 10.
The present study investigated whether engaging in a mindful breathing exercise would affect EEG oscillatory activity associated with self-monitoring processes, based on the notion that mindfulness enhances attentional awareness. Participants were assigned to either an audio exercise in mindful breathing or an audio control condition, and then completed a Stroop task while EEG was recorded. The primary EEG measure of interest was error-related alpha suppression (ERAS), an index of self-monitoring in which alpha power is reduced, suggesting mental engagement, following errors compared to correct responses.
View Article and Find Full Text PDFVisual experiences increase our ability to discriminate environmentally relevant stimuli (native stimuli, e.g., human faces) at the cost of a reduced sensitivity to irrelevant or infrequent stimuli (non-native stimuli, e.
View Article and Find Full Text PDFStreams collect runoff, heat, and sediment from their watersheds, making them highly vulnerable to anthropogenic disturbances such as urbanization and climate change. Forecasting the effects of these disturbances using process-based models is critical to identifying the form and magnitude of likely impacts. Here, we integrate a new biotic model with four previously developed physical models (downscaled climate projections, stream hydrology, geomorphology, and water temperature) to predict how stream fish growth and reproduction will most probably respond to shifts in climate and urbanization over the next several decades.
View Article and Find Full Text PDFWe report a severe hemorrhagic disorder in two pediatric patients with lupus anticoagulant (LA) associated to acquired factor II (prothrombin) deficiency. In both patients, hemorrhagic symptoms resolved after corticosteroid therapy. Serial coagulation studies showed that Staclot LA assay was more sensitive than DVVconfirm and Staclot PNP tests to confirm the presence of LA when associated with severe factor II deficiency.
View Article and Find Full Text PDFConsidering that the prevalence of some hematologic malignancies may have a geographic distribution that could be related with its etiology, a group of 2,387 patients with acute leukemia (1,968 adults and 419 children) was studied along a 5-year period in six different locations within México. Twenty-seven patients (16 males and 11 females) with hairy cell leukemia (HCL) were identified. The adjusted overall proportion of HCL, after excluding data from centers reporting only adults, was 1.
View Article and Find Full Text PDFAdult patients with chronic autoimmune thrombocytopenic purpura (ATP), which proved refractory to various treatments, received a single dose of autologous in vitro opsonized erythrocytes with 100 micrograms of anti-D IgG. In 1983, 30 of these patients were treated with autologous erythrocytes that had been opsonized and labeled with 25 mCi (740 MBq) of technetium Tc 99m; this treatment was designated as the radioimmune method. Favorable responses were noted in 36% of patients so treated.
View Article and Find Full Text PDFIdiopathic thrombocytopenic purpura (ITP) is more frequently seen in young females than in any other age or sex group. Danazol, an impeded androgen with a decreased masculinizing potential, has been described as useful in ITP. A total of 25 women 16 to 41 years of age, with chronic ITP were studied.
View Article and Find Full Text PDFAccessory spleens were sought in 28 patients who had undergone splenectomy for chronic idiopathic thrombocytopenic purpura (ITP), using a variety of techniques. Abdominal scintigraphy with autologous erythrocytes labeled with Tc-99m and opsonized with anti-D IgG (radioimmune method) proved to be most useful, clearly demonstrating one or more accessory spleens in 12 cases (43%). Computed tomography (CT) was also helpful.
View Article and Find Full Text PDFIn order to analyze the usefulness of different types of treatment in relation to the interval since the onset of idiopathic thrombocytopenic purpura (ITP), a collaborative study of 934 adult patients was undertaken. Prednisone was administered to 818 patients, and 32% of them achieved prolonged complete remission (PCR). However, only 14% of patients who had ITP for more than six months achieved a prednisone-induced PCR (P less than .
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