30 research outputs found
Preface
The distinguished authors of these tectonic studies, which span the United States from the Atlantic continental shelf margin to the Pacific coast, need no introduction to the geologic profession. Each was selected as a participant in the V. H. McNutt-Geology Department Colloquium because of his intimate knowledge and thorough research on the tectonic development of the area on which he reports. The authors publicly presented their papers during the Spring of 1966 on the campus of the University of Missouri at Rolla (formerly University of Missouri School of Mines and Metallurgy). The colloquium volume is unique in that such a distinguished group could be assembled and that each would consent to prepare his oral report for publication.
The “Geologic and Crustal Cross Section of the United States Along the 37th Parallel,\u27* published in 1965 by W. Hamilton and L. C. Pakiser as United States Geological Survey Miscellaneous Geologic Investigations Map 1-448, gives a broad geological and geophysical interpretation of the upper mantle and crust. The detailed reports and excellent illustrations in this volume should add needed details to the above generalized section and should lead to a better understanding of the tectonic development of this portion of the North American continent. Hopefully, the study can be used by the geologic profession and students as a reference.
Publication of these studies as the initial contribution of a continuing colloquium series is the culmination of the efforts and contributions of many people. Foremost among them is Mrs. V. H. McNutt, of Gallagher Ranch, San Antonio, Texas. The colloquium series has been made possible through her generosity and love for the Geology Department of the Missouri School of Mines and Metallurgy. In memory of Vachel Harry McNutt, student and former faculty member of the school, her husband and partner in developing the oil and mineral resources of the United States, and discoverer of the great potash deposits at Carlsbad, New Mexico, she named the Geology Department as beneficiary of the one million dollar V. H. McNutt Memorial it\u27oundation, the income to be used by the department.
Members of the V. H. McNutt Committee hope that this publication will be one way of helping the geologic profession benefit from some of the material wealth obtained by V. H. McNutt during his career through his practical understanding and use of geologic structures and stratigraphy.
The V. H. McNutt Committee --1966 T. R. Beveridge D. L. Frizzell R. E. Morgan P. D. Proctor, Chairman A. C. Spren
Preface
The UMR Journal has had an interesting but somewhat sporadic history. The topics of papers that appeared in UMR Journal 1 in 1968 under the general title of “A Coast to Coast Tectonic Study of the United States” covered the major tectonic features of the contiguous United States from the margin of the Atlantic continental shelf to the Pacific coast. Each paper was authored by a recognized expert for the specific province reviewed. UMR Journal 2, which was published in 1971, related to “Alaska—Its Mineral Potentials and Environmental Challenges”. This UMR Journal 3 emphasizes the geology, genesis, and energy resources of a marginal basin and selected interior basins in the midcontinental region of the United States. Authors of the papers were selected for their comprehensive knowledge of the subject areas. The papers were originally presented in a colloquium held in the Department of Geology and Geophysics at the University of Missouri-Rolla during September and October of 1980.
Because the Precambrian basement rocks as well as their composition and possible internal structures in the sites of the basins-to-be are considered essential to basin development, Edward C. Lidiak, a long-time researcher on the basement rocks of the Midcontinent and a contributor to the basement map of the United States,, initiated the colloquium. He was followed by L. L. Sloss, who described the backyard he knows so well, the Michigan basin. He succinctly and knowledgeably described this classic basin and the problems associated with developing a model capable of accommodating the known facts of its history.
Although a presentation was originally scheduled for the Illinois basin, factors beyond the control of the colloquium convener and the selected author required a modification of the subject matter. Hence, H. R. Schwalb of the Illinois State Geological Survey detailed the interface of the southern part of the Illinois basin with the Mississippi Embayment. He presented some intriguing views of this unique tectonic area of the Midcontinent.
Boyd R. Haley of the U.S. Geological Survey and semi-resident geologist of Arkansas most ably reviewed the results of his research on the Arkoma basin. He illuminated the contrasts that exist between a basin that is marginal to a mobile belt and a basin that is located on a craton.
The relatively young and less geologically developed Forest City-Salina basins were described by Don W. Steeples of the Kansas Geological Survey. His broad ranging report on the geology and geophysics of these basins brought forth some novel concepts concerning the development of the basins and their energy resources.
The topic of the final presentation of the colloquium was concerned mainly with the North Dakota portion of the Williston basin. Because of the renewed and successful exploration efforts being expended within this basin, this presentation by Lee C. Gerhard of the North Dakota Geological Survey and University of North Dakota was and should be of particular interest to members of the profession. He thoroughly documented his subject and added new approaches to the solution of problems related to basin development and energy sources.
We believe that this printed record of these presentations will be read with interest by members of the geologic profession, in industry, government, and academia. It is our hope that it will assist in the understanding of the geology and genesis of the basins and in the continued development of their energy resources.
The V. H. NcNutt Colloquium series has been sponsored by the V. H. McNutt Memorial Foundation, which was initially established for the Department of Geology of the University of Missouri School of Mines and Metallurgy, now the University of Missouri-Rolla, through the generosity and thoughtfulness of Mrs. V. H. McNutt, wife of the late Vachael H. McNutt, well known as “Mac”. It was he who discovered the Carlsbad potash salt deposits and numerous oil and gas fields in the United States. Mac was a graduate of the Missouri School of Mines and Metallurgy in 1912 and was a member of the faculty of the Department of Geology before beginning his eminently successful consulting career. His co-worker, Mrs. Mac, as she is affectionately known, established the V. H. McNutt Memorial Foundation in his memory, stating that she wanted to show in some form more concrete than words the debt that both of them owed to the Department for the training Mac had received.
Income from the Foundation has been a great boon to hundreds of students in geology. It has provided them with undergraduate scholarships, summer field camp scholarships, graduate fellowships, and other forms of financial aid. The Department also benefits, because it can invite special speakers, purchase selected equipment, support short course attendance for its faculty, and obtain supplemental items, all through the income from the Foundation. It is also because of this income that even a larger segment of the geologic profession can benefit through the publication of the papers presented in colloquiums such as these. To Mrs. Mac, wise counselor and dear friend, and to her late husband, Mac we are ever grateful.
Paul Dean ProctorJohn W. KoenigEditors.
The V. H. McNutt Committee - 1982Department of Geology and GeophysicsUniversity of Missouri-RollaS. K. GrantR. E. Morgan, ChairmanG. E. RupertPaul Dean ProctorA. C. Spren
Preface
Because this university, formerly under the well known title of Missouri School of Mines and Metallurgy, has contributed so much to the nation’s and world’s mineral supplies through the work of its well trained graduates, it was considered appropriate that a major symposium be held during its Centennial Year on one of the last major mineral frontiers of the United States......Alaska.
Preliminary planning for the symposium on “Alaska, Its Mineral Potentials and Environmental Challenges” began in the fall of 1969. In January, 1970, Robert E. Carlile and Paul Dean Proctor visited Alaska to meet with some of the petroleum and mineral industry personnel. The purpose of the journey was to personally invite some of the experts who could directly relate to this Centennial Symposium. The warm hospitality, graciousness, and suggestions of industry and government leaders gave much impetus to the finalization of the program and the plans.
Formal invitations were extended to various individuals who had in-depth experience in Alaska or direct interest in the Arctic areas to participate in this Centennial Symposium. Objectives were to give platform presentation and audience discussion to important aspects of the petroleum-solid mineral potential of this frontier state of America and the adjacent arctic lands and continental shelf. Because of the unusual climatic setting other speakers were invited to discuss the challenges of this environment in discovering, recovering, and transporting the potential mineral wealth of Alaska. The state consists mainly of public domain and state lands, hence other speakers were invited to present the government’s views on oil and gas developments on these lands and the Alaskan business communities viewpoint on the possible future progress of Alaska.
Special recognition has been given the various authors of the papers, but exceptional efforts were extended by the moderators who so ably assisted in the symposium presentation. Short biographical and alphabetically listed sketches are included for each of the external moderators with our sincere thanks for their considerable help. Similar concise biographical information on each of the authors is included at the end of each of the papers.
The paper presentations includes an introductory paper on Arctic Ecology, by Dr. John Schindler, Assistant Director of the Naval Research Laboratory, Point Barrow, Alaska. Regrettably, Dr. Max Brewer, Director, Naval Research Laboratory was unable to include his presentation on “What We Should Know About the Arctic Environment”. Following the ecological paper, George Gryc and A1 Weissenborn of the U.S. Geological Survey present data on the energy fuels and solid mineral potentials of Alaska. Dr. Earl Hayes, Chief Scientist of the U.S. Bureau of Mines then relates to the environmental challenges of Alaskan mineral resources. Co-authors, Drs. R. G. McCrossan and R. Procter, of the Canadian Geological Survey, review the mineral potential of Arctic Canada. Dr. A. J. Eardley’s paper on Oil and Gas Reserves in the Siberian Shelf extends the prognostications on the Arctic basin. The latter author specifically asked that it be indicated he was substituting for Russian authors who had been invited but could not attend.
With the good potential for petroleum which exists, consideration was then given to physical exploration by drilling and to the unique problems encountered in the handling of equipment under the rigorous arctic conditions. Robert L. Parker, President of the Parker Drilling Company discusses problems in such an environment. Charles C7 Norris of William Brothers Engineering Company describes the maintenance and operation of facilities and equipment in the Arctic. William Pearn discusses details of “Pipeline Design for Arctic and Subarctic Regions”, and A. V. Cardin, Chief Engineer, TAPS, specifically relates to the environmental challenges facing construction of TAPS. Russell Venn, Vice President, Humble Oil Company, expertly discussed details of the epic voyage of the S. S. Manhattan through the Northwest passage. With the possibility that oil might be transported by ship or submarine from northern Alaska, Robert L. McCollom and William Moore present interesting views on arctic marine terminals and their environmental and engineering considerations.
The practicalities and experience of handling petroleum products under conditions varying from arctic conditions to almost temperate conditions and some of the problems related to pipeline construction and pumping of oil products is dynamically presented by Colonel Frederic Johnson, Chief, Petroleum Supply, U.S. Army. Don Simasko gives his views on the place of the independent operator in this developing region with its attendent problems. Thomas R. Marshall, representing the State of Alaska, succinctly and expertly discusses the regulatory controls on oil and gas in the state.
Mr. W. H. Scott, President of the Alaskan Chamber of Commerce, concisely describes the Alaskan business communities view on the petroleum mineral resource development of his state. The final paper, by C. O. Banks, representing the Anchorage Chamber of Commerce, spells out the optimism of the good people of a great state as it moves into its stride in the 20th century.
These thoughts, views and warnings on “Alaska - Its Mineral Potentials - Its Environmental Challenges” are, therefore, presented in the hope that the reader will gain a deeper appreciation and awareness of Alaska - truly one of the last frontiers of today where, most appropriately, the words of J. Robert Oppenheimer apply:
“Both the man of science and the man of action live always at the edge of mystery, surrounded by it.”
Paul Dean ProctorR. E. Carlil
Heavy metals in the main streams of the James River Basin, Missouri
Demand for water in the James River basin has greatly increased. Larger numbers of industrial plants and the presence of lead-zinc prospects in the basin are potential sources of heavy metal additions to the waters of the area. This study determines selected heavy metal content and distribution in the streams of the basin and establishes some heavy metal bench mark values for this time period. Approximately 50 water samples were collected in each of three seasons. These samples were analyzed by atomic absorption techniques. Temperature, specific conductance, pH, and effective alkalinity were made in the field. Ranges of heavy metal content were: (1) mercury - [less than] 0.1 to 0.3 ppb (summer only); (2) zinc - [less than] 1 to 80 ppb; (3) copper - [less than] 1 to 18 ppb; (4) lead - [less than] 1 to 41 ppb; (5) cadmium- [less than] 1 to 7 ppb; and (6) iron [less than] 50 to 277 ppb. The urban areas of Springfield contribute dissolved heavy metals to the surface streams. The Southwest Springfield Sewage Treatment Plant is not a significant source. Seasonal and geographic variations are also apparent. Heavy metal contributions appear to be related to mineralized and faulted areas in the basin. Variation of heavy metals at individual sample sites is not considered of great significance. Filtered water samples meet PHS heavy metal standards for public drinking water.Project # A-066-MO Agreement # 14-31-0001-382
Water quality as related to possible heavy metal additions in surface and ground water in the Springfield and Joplin areas, Missouri
Students supported: 3 MS StudentsSome 165 seasonal water samples were collected and analyzed for heavy metals from surface and subsurface sources in a one hundred mile area around Springfield and Joplin, Missouri, respectively. Joplin is in a former large zinc mining district. Springfield is 72 miles east. Locally, cadmium, lead, zinc and iron exceed acceptable PHS standards for drinking water, but the majority of water samples are well within the established limits. Yet, ten percent of the water wells sampled in the Springfield area and twenty-five percent of those sampled in the Joplin area approached or exceeded the PHS limits of the one or more heavy metals for drinking water. High zinc values are related to known zinc-lead mineralization in both areas. Average cadmium values are slightly higher in Joplin, copper content is similar for both areas, and lead content is slightly higher near Joplin. Surface waters in Joplin are 17 times higher in average zinc content than in Springfield, though shallow wells for both areas are similar in zinc content. Iron is higher and more variable in Joplin. Mercury, in very low quantity in both areas, is somewhat higher in the Springfield area. Some seasonal variation occurs in the heavy metal content in both areas. Alternate sources of water are suggested or those areas having heavy metal content in excess of PHS standards. Effects on living systems within areas containing anomalous heavy metal content are unknown.Project # B-054-MO Agreement # 14-31-0001-360
Transmission pathways for sporadic Shiga-toxin producing E. coli infections: A systematic review and meta-analysis
Background: Shiga-toxin E. coli infections remain a public health concern because of the severity of the gastrointestinal illness and associated complications. Transmission pathways are typically elucidated from outbreaks, with foodborne transmission the primary source. However, most STEC cases are sporadic. This systematic review aimed to identify the most common pathways for sporadic STEC transmission and quantify their importance. Methods: We systematically reviewed epidemiological studies of sporadic (non-outbreak) STEC cases that investigated potential risk factors. Searches were run in Medline, EMBASE, and Scopus. Included studies needed to confirm STEC infection and investigate ≥20 cases. Results: 31 studies were included, of which 25 were case-control or case-case studies. 62.5% found consumption of undercooked/raw meat associated with STEC infection while 70.4% found contact with animals or their environment a risk factor. Random-effects meta-analysis provided pooled odds ratios and population attributable fraction (PAF). The PAF was 19% for undercooked/raw meat, followed by person to person transmission at 15%. Contact with animals and visiting farm environments had PAFs of 14% and 12% respectively. Conclusions: Out of potential sources for STEC exposure, undercooked meat and contact with animals and their environment were the most frequently found transmission routes. Decreasing the chances of acquiring the bacteria by these methods would additionally cut down on the other major transmission route, person-to-person spread
Phenotypic and Genome-Wide Analysis of an Antibiotic-Resistant Small Colony Variant (SCV) of Pseudomonas aeruginosa
Small colony variants (SCVs) are slow-growing bacteria, which often show increased resistance to antibiotics and cause latent or recurrent infections. It is therefore important to understand the mechanisms at the basis of this phenotypic switch.One SCV (termed PAO-SCV) was isolated, showing high resistance to gentamicin and to the cephalosporine cefotaxime. PAO-SCV was prone to reversion as evidenced by emergence of large colonies with a frequency of 10(-5) on media without antibiotics while it was stably maintained in presence of gentamicin. PAO-SCV showed a delayed growth, defective motility, and strongly reduced levels of the quorum sensing Pseudomonas quinolone signal (PQS). Whole genome expression analysis further suggested a multi-layered antibiotic resistance mechanism, including simultaneous over-expression of two drug efflux pumps (MexAB-OprM, MexXY-OprM), the LPS modification operon arnBCADTEF, and the PhoP-PhoQ two-component system. Conversely, the genes for the synthesis of PQS were strongly down-regulated in PAO-SCV. Finally, genomic analysis revealed the presence of mutations in phoP and phoQ genes as well as in the mexZ gene encoding a repressor of the mexXY and mexAB-oprM genes. Only one mutation occurred only in REV, at nucleotide 1020 of the tufA gene, a paralog of tufB, both encoding the elongation factor Tu, causing a change of the rarely used aspartic acid codon GAU to the more common GAC, possibly causing an increase of tufA mRNA translation. High expression of phoP and phoQ was confirmed for the SCV variant while the revertant showed expression levels reduced to wild-type levels.By combining data coming from phenotypic, gene expression and proteome analysis, we could demonstrate that resistance to aminoglycosides in one SCV mutant is multifactorial including overexpression of efflux mechanisms, LPS modification and is accompanied by a drastic down-regulation of the Pseudomonas quinolone signal quorum sensing system
Phylogenetic ctDNA analysis depicts early-stage lung cancer evolution.
The early detection of relapse following primary surgery for non-small-cell lung cancer and the characterization of emerging subclones, which seed metastatic sites, might offer new therapeutic approaches for limiting tumour recurrence. The ability to track the evolutionary dynamics of early-stage lung cancer non-invasively in circulating tumour DNA (ctDNA) has not yet been demonstrated. Here we use a tumour-specific phylogenetic approach to profile the ctDNA of the first 100 TRACERx (Tracking Non-Small-Cell Lung Cancer Evolution Through Therapy (Rx)) study participants, including one patient who was also recruited to the PEACE (Posthumous Evaluation of Advanced Cancer Environment) post-mortem study. We identify independent predictors of ctDNA release and analyse the tumour-volume detection limit. Through blinded profiling of postoperative plasma, we observe evidence of adjuvant chemotherapy resistance and identify patients who are very likely to experience recurrence of their lung cancer. Finally, we show that phylogenetic ctDNA profiling tracks the subclonal nature of lung cancer relapse and metastasis, providing a new approach for ctDNA-driven therapeutic studies
Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.
BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112
Pooled analysis of WHO Surgical Safety Checklist use and mortality after emergency laparotomy
Background The World Health Organization (WHO) Surgical Safety Checklist has fostered safe practice for 10 years, yet its place in emergency surgery has not been assessed on a global scale. The aim of this study was to evaluate reported checklist use in emergency settings and examine the relationship with perioperative mortality in patients who had emergency laparotomy. Methods In two multinational cohort studies, adults undergoing emergency laparotomy were compared with those having elective gastrointestinal surgery. Relationships between reported checklist use and mortality were determined using multivariable logistic regression and bootstrapped simulation. Results Of 12 296 patients included from 76 countries, 4843 underwent emergency laparotomy. After adjusting for patient and disease factors, checklist use before emergency laparotomy was more common in countries with a high Human Development Index (HDI) (2455 of 2741, 89.6 per cent) compared with that in countries with a middle (753 of 1242, 60.6 per cent; odds ratio (OR) 0.17, 95 per cent c.i. 0.14 to 0.21, P <0001) or low (363 of 860, 422 per cent; OR 008, 007 to 010, P <0.001) HDI. Checklist use was less common in elective surgery than for emergency laparotomy in high-HDI countries (risk difference -94 (95 per cent c.i. -11.9 to -6.9) per cent; P <0001), but the relationship was reversed in low-HDI countries (+121 (+7.0 to +173) per cent; P <0001). In multivariable models, checklist use was associated with a lower 30-day perioperative mortality (OR 0.60, 0.50 to 073; P <0.001). The greatest absolute benefit was seen for emergency surgery in low- and middle-HDI countries. Conclusion Checklist use in emergency laparotomy was associated with a significantly lower perioperative mortality rate. Checklist use in low-HDI countries was half that in high-HDI countries.Peer reviewe