Holocene Pedogenesis in Fluvial Deposits of the Conejos River Valley, Southern Colorado

Relatively few geomorphic studies have examined Holocene-aged soils developed in alluvial deposits in the Rocky Mountains. Here, we present a soil morphological investigation from a suite of fluvial terraces in the glaciated portion of the Conejos River Valley, southern Colorado. The surficial geology of 25 km of the glacial valley was mapped in detail. Within three separate sub-reaches (Platoro, Lake Fork and South Fork) a total of thirteen soil pits and exposures were excavated and described on alluvial deposits. Soil samples were analyzed for particle size and extractable iron. Soil horizonation (A/C to A/B/2C), structure (fine sub angular to medium angular blocks), clay content of the B horizon (8.0% to 22.8%) and Feo/Fed (0.39 to 0.80) illustrate trends with relative terrace deposit age in individual sub-reaches. However, only Feo/Fed ratios displayed similar rates of development between all sub-reaches highlighting the usefulness of this metric for determining accurate rates of pedogenesis and relative age for Holocene-aged deposits in sub-alpine environments. Results indicate that clay content and structure developed in alluvial deposits of similar ages vary between sub-reaches. Clay contents were found to be lower in the Platoro sub-reach (e.g. 13.1% at Platoro and 20.0% at South Fork on Qt1 deposits). This variation is attributed to heterogeneity in the nature of the inherited parent material and potential variability in aeolian dust contributions throughout the Holocene

Ochrobactrum anthropi bacteremia in a child.

Children undergoing chemotherapy for cancer are at increased risk of supervening infection, including bacteremia. This may be due to immunosuppression as well as the presence of intravascular devices such as central venous catheters. Bacteria responsible for these infections include those found in the child\u27s endogenous flora as well as in environmental sources. We report the case of a child with acute lymphoblastic leukemia (ALL) who developed bacteremia secondary to Ochrobactrum anthropi. Details of this extremely rare infection are the focus of this report

Childhood typhoid fever diagnosed in an urban U.S. setting.

The majority of cases of childhood typhoid fever diagnosed in the United States occur in persons recently returned from travel abroad. We report two childhood cases of typhoid fever acquired in Mexico and India and diagnosed in an urban United States setting. This report describes these cases and provides insights into the pitfalls in recognizing this condition in a nonendemic setting as well as information concerning differential diagnosis and treatment

A clustering of childhood meningococcal disease: a challenge for physicians, press and community.

The Delaware Division of Public Health reported only two cases of documented meningococcal infection in the pediatric population in 1992. As of March 1, 1993, the Morbidity and Mortality Weekly Report indicated only one case of meningococcal disease in the state of Delaware for 1993. However, from the end of February to early April 1993, approximately six weeks, there were seven cases of documented meningococcal infection in the pediatric population that either presented or were transferred to one of the pediatric care facilities in the Wilmington, Delaware area. Notification of these cases to the Delaware Division of Public Health prompted the dispersion of a statewide letter concerning the recognition of the clinical signs of meningitis and the proper prophylaxis for meningococcal exposure

Germbuster Brainteaser: A Novel Education Tool

As part of the Pediatric Infectious Diseases elective at the Alfred I. duPont Institute, pediatric residents from the Medical Center of Delaware and the Thomas Jefferson Medical College are encouraged to contribute original, educational material to our Germbusters newsletters. We thought readers of the Delaware Medical Journal would enjoy seeing one of the more innovative resident contributions

Recurrent/persistent pneumonia in a 3 1/2-year-old-girl due to acquired immune deficiency syndrome.

The following is the report of the first case of a Delaware born child who developed AIDS, born from a mother who was not in a high risk camp

Introducing standardized field methods for fracture-focused surface process research

Rock fractures are a key contributor to a broad array of Earth surface processes due to their direct control on rock strength as well as rock porosity and permeability. However, to date, there has been no standardization for the quantification of rock fractures in surface process research. In this work, the case is made for standardization within fracture-focused research, and prior work is reviewed to identify various key datasets and methodologies. Then, a suite of standardized methods is presented as a starting “baseline” for fracture-based research in surface process studies. These methods have been shown in pre-existing work from structural geology, geotechnical engineering, and surface process disciplines to comprise best practices for the characterization of fractures in clasts and outcrops. This practical, accessible, and detailed guide can be readily employed across all fracture-focused weathering and geomorphology applications. The wide adoption of a baseline of data collected using the same methods will enable comparison and compilation of datasets among studies globally and will ultimately lead to a better understanding of the links and feedbacks between rock fracture and landscape evolution.</p