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Subsurface microbial (biogenic) methane production is an important part of the global carbon cycle that has resulted in natural gas accumulations in many coal beds worldwide. Laboratory studies suggest that complex carbon-containing nutrients (e.g., yeast or algae extract) can stimulate methane production, yet the effectiveness of these nutrients within coal beds is unknown. Here, we use downhole monitoring methods in combination with deuterated water (D2O) and a 200-liter injection of 0.1% yeast extract (YE) to stimulate and isotopically label newly generated methane. A total dissolved gas pressure sensor enabled real-time gas measurements (641 days preinjection and for 478 days postinjection). Downhole samples, collected with subsurface environmental samplers, indicate that methane increased 132% above preinjection levels based on isotopic labeling from D2O, 108% based on pressure readings, and 183% based on methane measurements 266 days postinjection. Demonstrating that YE enhances biogenic coalbed methane production in situ using multiple novel measurement methods has immediate implications for other field-scale biogenic methane investigations, including in situ methods to detect and track microbial activities related to the methanogenic turnover of recalcitrant carbon in the subsurface.

Summary In this manuscript, we describe the second of two field demonstrations of microbially induced calcium carbonate precipitation (MICP) performed in a failed waterflood injection well in Indiana. In 2012, fracture-related flow pathways developed in the wellbore cement, causing injection water to bypass the oil-bearing formation and enter a high-permeability sandstone thief zone, thereby substantially decreasing injection pressure. In the first field demonstration, our study team characterized the well's mode of failure and successfully applied MICP to decrease flow through the defective cement. However, because the MICP treatment was conducted using a bailer delivery system, the degree of permeability reduction achievable was not adequate to fully restore the historic injection pressure of 1,400 psi at 1 gal/min. For the second field demonstration (reported herein), a direct injection system was developed that substantially increased the injection volume of MICP-promoting fluids. Two strategies were implemented to produce more ureolytic microbes: resuspending concentrated frozen cells immediately before injection and scaling up the bioreactor growth capacity. Multiple pulses of microbes and urea-calcium media were pumped into a string of 1-in.-diameter tubing separated by brine spacers and injected continuously at a flow rate of 3.4 to 1.4 gal/min. During the third day of injection, an injection pressure of 1,384 psi at a flow rate of 1.4 gal/min was achieved, and the experiment was terminated. This study demonstrates that MICP can be successfully used in large-volume applications where the time frame for the delivery of reactants is limited. This finding has significant relevance for commercialization of the MICP biotechnology in the oil and gas industry.

The etiology of minimal lesion nephrosis (MLN), the most common cause of nephrotic syndrome in children, is unknown. The only incidence data on MLN have been extrapolated from population surveys of nephrotic syndrome in childhood performed over 20 years ago. These studies estimated the incidence of MLN at 1.5 cases per year per 100,000 children, ages 1-9. New cases of MLN occurring during the years 1970-1979 were identified by survey of area pediatricians and by medical record review of 9 hospitals in the area most likely to care for children. Total population of the study area in 1974 was 1.1 million with 187,000 children, ages 1-9. Thirty-five cases of MLN were identified with onset after first and before tenth birthday. Criteria for identification were initial response to daily steroids (33 pts) with complete clearing of proteinuria in <1 month or initial non-response (2 pts) with both renal biopsy and subsequent clinical course compatible with MLN. Incidence of MLN in the study area was 1.9 cases per year per 100,000 children, ages 1-9. However, in one rural 5-county area the incidence was 4.7 cases per year per 100,000. Whether this cluster of cases is epidemiologically meaningful or a statistical artifact is uncertain. Further refinement of the distribution and demographics of cases in the high rate area may provide clues to the etiology of MLN and continuing surveillance of area will enable us to assess the reliability of the finding. NOSOCQ\lIAL SCABIES INFECTIONS: EPIDEMIOLOGY IN THE 502 OUTPATIENT CLINIC. T. Yamauchi K. Eisenach, and S. Furr, Departments 07 P-; GdPediatric PatFol-o w , Universityof AGkansas Medical Sciences and Arkansas Child-ren's ~ospital; Little Rock, Arkansas. Scabies infestation appears to be increasing over the past few years. Nosocomial spread of this disease has been rarely reported. In October of 1978, 2 nurses and a medical student developed pruritic, papular eruptions on wrists, shoulders, neck and axil-lary areas. Scabies was diagnosed in each case by clinical and microscopic findings. Since all 3 of these individuals were assigned to the general pediatric outpatient clinic, an epidemio-logic investigation was initiated. Both nurses and the medical student remembered prolonged close contact (during lumbar puncture procedure) with a 6-year-old child with aseptic meningitis and scabies. Thls index child had been diagnosed infested with scabies 24 hours previously, but had not received the prescribed treatment. A total of 41 persons who had both direct and indirect contact with the scabietic child were identified and examined. Scabies was diagnosed in 12 cases: 6 family members of the index child, 5 family members of the nurses, and a single child visiting one of the infested children. Topical application of 1% gamma benzene hexachloride was initiated for all diagnosed individuals and persons sharing living facilities were simultaneously treated to avoid reinfection. A re-education of staff, stressing the importance of proper handling of infected and suspected patients was ini...