bluuebunny/crossref_metadata_2025 huggingface dataset:
Possible roles of Juvenile Hormone and Juvenile Hormone binding protein on changes in the integument during termination of larval diapause in the bamboo borer Omphisa fuscidentalis
Authors: RITDACHYENG EAKARTIT , MANABOON MANAPORN , TOBE STEPHEN S. , SINGTRIPOP TIPPAWAN
Published: April 2013

To understand the role of Juvenile Hormone (JH) on changes in the integument of Omphisa fuscidentalis Hampson (Lepidoptera: Pyralidae) during larval–pupal development, the expression patterns of transcripts of the O. fuscidentalis JH binding protein gene (OfJHBP) are determined in the integument of diapausing larvae. Quantitative real‐time polymerase chain reaction (qRT‐PCR) studies show that the relative levels OfJHBP mRNA in the integument do not differ significantly in different segments of the body. Application of the JH analogue (JHA) methoprene to diapausing larvae results in a relatively low expression of OfJHBP mRNA from days 0 to 8 after JHA application and reaches maximal levels in the pupal stage. Changes in OfJHBP expression after 20‐hydroxyecdysone (20E) injection also show low levels of OfJHBP mRNA from days 0 to 8 and show a peak of expression in the pupal stage. Incubation of the integument in vitro in the presence of JHA (3.22 µm) induces high levels of OfJHBP expression within 120 min, whereas incubation with 20E (2.08 µm) induces gene expression at 150 min. To study the cooperative effect on OfJHBP expression of these two hormones, dose–response experiments are performed. Larval integument is maintained in the presence of 0.32 µm JHA or 2.08 µm 20E or a combination of both hormones in vitro for 120 min. Induction of OfJHBP expression by JHA and 20E in combination is significantly higher than that of either hormone alone. The results impact not only on our understanding of how methoprene (and hence JH) terminates larval diapause through an increase in ecdysteroid titre in the haemolymph, but also on how JH acts directly on the integument to stimulate the expression of a JH binding protein gene.
Broadband Network Management and the Net Neutrality Debate
Authors: Guo Hong , Cheng Hsing Kenneth , Bandyopadhyay Subhajyoti
Published: April 2013

The debate of net neutrality and the potential regulation of net neutrality may fundamentally change the dynamics of data consumption and transmission through the Internet. The existing literature on economics of net neutrality focuses only on the supply side of the market, that is, a broadband service provider (BSP) may charge content providers for priority delivery of their content to consumers. In this article, we explore a complete spectrum of broadband network management options based on both the supply and demand sides of the market. We find that although the BSP always prefers the non‐neutral network management options, it does not always discriminate both sides of the market. From the social planner's perspective, we find that some network management options maximize the social welfare under certain market conditions while other options reduce the social welfare. Using the terminology from a recent Federal Communications Commission report and order, we categorize the social welfare maximizing options as “reasonable network management” and the social welfare reducing options as “unreasonable discrimination.” We also identify conditions under which the BSP's network management choices deviate from the social optimum. These conditions help establish the criteria under which the social planner might wish to regulate the BSP's actions.
Transcriptional regulation of the V‐ATPase subunit c and V‐PPase isoforms in Cucumis sativus under heavy metal stress
Authors: Kabała Katarzyna , Janicka‐Russak Małgorzata , Reda Małgorzata , Migocka Magdalena
Published: April 2013

Two electrogenic proton pumps, vacuolar H+ transporting ATPase (V‐ATPase, EC 3.6.3.14) and vacuolar H+ transporting inorganic pyrophosphatase (V‐PPase, EC 3.6.1.1), co‐exist in the vacuolar membrane of plant cells. In this work, all CsVHA and CsVHP genes encoding V‐ATPase and V‐PPase, respectively, were identified in the cucumber genome. Among them, three CsVHA‐c genes for V‐ATPase subunit c and two CsVHP1 genes for type I V‐PPase were analyzed in detail. Individual isogenes were differentially regulated in plant tissues and during plant development as well as under changing environmental conditions. CsVHA‐c1 and CsVHA‐c2 showed similar tissue‐specific expression patterns with the highest levels in stamens and old leaves. CsVHP1;1 was predominantly expressed in roots and female flowers. In contrast, both CsVHA‐c3 and CsVHP1;2 remained in a rather constant ratio in all examined cucumber organs. Under heavy metal stress, the transcript amount of CsVHA‐c1 and CsVHP1;1 showed a pronounced stress‐dependent increase after copper and nickel treatment. CsVHA‐c3 was upregulated by nickel only whereas CsVHA‐c2 was induced by all metals with the most visible effect of copper. Additionally, CsVHP1;2 showed a tendency to be upregulated by copper and zinc. We propose that CsVHA‐c1, CsVHA‐c2 and CsVHP1;1 are essential elements of mechanisms involved in adaptation of cucumber plants to copper toxicity.
The art of friendship: Daniel Nijs, Isaac Wake and the sale of the Gonzaga collection
Authors: Anderson Christina M.
Published: April 2013

The 1627–28 sale of the cream of the Gonzaga art collection belonging to the Dukes of Mantua was, arguably, the greatest art transaction of the seventeenth century. Many theories have been put forward by scholars as to the origins of the sale. However, the friendship between Daniel Nijs, the Flemish merchant in Venice who brokered the sale, and Isaac Wake, the English ambassador in Venice at the time, has largely been overlooked. This article will trace the development of their friendship from its beginnings during Wake's employment as secretary to Dudley Carleton, English ambassador in Venice between 1610 and 1615, through Wake's subsequent posting to Turin and his return to Venice as ambassador himself in 1625. Wake held Nijs in high esteem and was in a position to recommend the Fleming's services favourably to his fellow Englishmen. The Gonzaga sale needs to be understood against this background.
Bayesian Ranking Responses in Multiple-Response Questions
Authors: Wang Hsiuying , Huang Wei Heng
Published: April 2013

Questionnaires are important surveying tools that are used in numerous studies. Analyses of multiple-response questions are not as well established in detail compared with single-response questions. Wang has proposed several methods for ranking responses in multiple-response questions under the frequentist set-up. However, prior information may exist for ranks of responses in numerous situations. Therefore, establishing a methodology that combines updated survey data and past information for ranking responses is an essential issue in questionnaire data analysis. This study develops Bayesian ranking methods based on several Bayesian multiple-testing procedures to rank responses by controlling the posterior expected false discovery rate. Moreover, a simulation is conducted to compare these approaches, and a real data example is presented to show the effectiveness of the methods proposed.
External validation and updating of a Dutch prediction model for low hemoglobin deferral in Irish whole blood donors
Authors: Baart A. Mireille , Atsma Femke , McSweeney Ellen N. , Moons Karel G.M. , Vergouwe Yvonne , de Kort Wim L.A.M.
Published: April 2013

Background

Recently, sex‐specific prediction models for low hemoglobin (Hb) deferral have been developed in Dutch whole blood donors. In the present study, we validated and updated the models in a cohort of Irish whole blood donors.

Study Design and Methods

Prospectively collected data from 45,031 Irish whole blood donors were used. Hb cutoff levels for donation were approximately 0.35 mmol/L lower in Ireland than the Dutch cutoff levels (8.07 mmol/L vs. 8.40 mmol/L in men; 7.45 mmol/L vs. 7.80 mmol/L in women). The predictive performance of the models was assessed with calibration plots, calibration‐in‐the‐large, and the concordance (c)‐statistic. The models were updated by revising the strength of the individual predictors in the models.

Results

A total of 613 men (2.4%) and 1624 women (8.4%) were deferred from donation because of a low Hb level. Validation demonstrated underestimation of predicted risks and lower c‐statistics for men and women compared to the Dutch cohort. The strength of most predictive factors, particularly previous Hb level, was lower in Irish donors. The updated models showed a c‐statistic of 0.83 (95% confidence interval [CI], 0.81‐0.84) for men and 0.76 (95% CI, 0.74‐0.77) for women.

Conclusion

The performance of Dutch prediction models for Hb deferral was limited when validated in Irish whole blood donors. Updating the models resulted in different predictor effects. This improved mainly the model calibration; the improvement in discrimination was small.
Quantification and comparison of baseline cortisol levels between aqueous and plasma from healthy anesthetized hound dogs utilizing mass spectrometry
Authors: Claude Andrew K. , Miller William W. , Beyer Anne M. , Willeford Kenneth O. , Ross Matthew K.
Published: April 2013

Objective

The purpose of this study is to quantify and compare the resting cortisol levels between aqueous (Aq) and plasma of anesthetized hound dogs utilizing mass spectrometry.

Animals

Nine hound breed dogs weighing between 20.8 and 29.2 kg ( = 26.3 kg, SD ± 2.6 kg) were utilized from a previous project.

Procedures

All dogs underwent two anesthesia sessions to harvest Aq from each eye respectively. A paired blood sample was taken immediately after aqueous centesis. The Aq and plasma were analyzed for cortisol levels using mass spectrometry. Correlation of cortisol levels in dog serum and ocular fluid was determined with Sigma Stat using Pearson's correlation analysis. The level of significance for correlation analysis was set atP < 0.05.

Results

The plasma resting cortisol levels in the dog ranged from 3.59 to 89.35 nm( = 31.68 nm, SD ± 28.53 nm), while the Aq cortisol levels ranged from 0.82 to 5.62 nm( = 2.73 nm, SD ± 1.94 nm). The correlation of cortisol levels in Aq compared to plasma was significant (P = 0.008) with a correlation coefficient ofr = 0.779. Based on these results, 61% (r = 0.7792) of the variation in Aq cortisol levels is explained by the variations in plasma cortisol levels.

Conclusion and Clinical Relevance

This study identified significant levels of cortisol in the Aq of the canine eye and positively correlated them with plasma cortisol levels. The dog may offer a representative model for further studies to help clarify the overall role of cortisol in the anterior chamber.
Effectiveness of robust optimization in intensity‐modulated proton therapy planning for head and neck cancers
Authors: Liu Wei , Frank Steven J. , Li Xiaoqiang , Li Yupeng , Park Peter C. , Dong Lei , Ronald Zhu X. , Mohan Radhe
Published: April 2013

Purpose:

Intensity‐modulated proton therapy (IMPT) is highly sensitive to uncertainties in beam range and patient setup. Conventionally, these uncertainties are dealt using geometrically expanded planning target volume (PTV). In this paper, the authors evaluated a robust optimization method that deals with the uncertainties directly during the spot weight optimization to ensure clinical target volume (CTV) coverage without using PTV. The authors compared the two methods for a population of head and neck (H&N) cancer patients.

Methods:

Two sets of IMPT plans were generated for 14 H&N cases, one being PTV‐based conventionally optimized and the other CTV‐based robustly optimized. For the PTV‐based conventionally optimized plans, the uncertainties are accounted for by expanding CTV to PTV via margins and delivering the prescribed dose to PTV. For the CTV‐based robustly optimized plans, spot weight optimization was guided to reduce the discrepancy in doses under extreme setup and range uncertainties directly, while delivering the prescribed dose to CTV rather than PTV. For each of these plans, the authors calculated dose distributions under various uncertainty settings. The root‐mean‐square dose (RMSD) for each voxel was computed and the area under the RMSD‐volume histogram curves (AUC) was used to relatively compare plan robustness. Data derived from the dose volume histogram in the worst‐case and nominal doses were used to evaluate the plan optimality. Then the plan evaluation metrics were averaged over the 14 cases and were compared with two‐sided pairedt tests.

Results:

CTV‐based robust optimization led to more robust (i.e., smaller AUCs) plans for both targets and organs. Under the worst‐case scenario and the nominal scenario, CTV‐based robustly optimized plans showed better target coverage (i.e., greater D95%), improved dose homogeneity (i.e., smaller D5% − D95%), and lower or equivalent dose to organs at risk.

Conclusions:

CTV‐based robust optimization provided significantly more robust dose distributions to targets and organs than PTV‐based conventional optimization in H&N using IMPT. Eliminating the use of PTV and planning directly based on CTV provided better or equivalent normal tissue sparing.
Turn Off Youth
Authors: Hines Pamela J.
Published: April 2013

Reciprocal signals promote axon regeneration in young worms and repress axon regeneration in older worms.
TPL2, a MAPKKK That Suppresses Lung Cancer
Authors: Ferrarelli Leslie K.
Published: April 2013

The kinase TPL2 suppresses lung carcinogenesis by promoting the stability of p53.
Impact of the MIC of Piperacillin-Tazobactam on the Outcome of Patients with Bacteremia Due to Extended-Spectrum-β-Lactamase-Producing Escherichia coli
Authors: Retamar Pilar , López-Cerero Lorena , Muniain Miguel Angel , Pascual Álvaro , Rodríguez-Baño Jesús ,   the ESBL-REIPI/GEIH Group
Published: April 2013

We investigated the impact of the piperacillin-tazobactam MIC in the outcome of 39 bloodstream infections due to extended-spectrum-β-lactamase-producing
Escherichia coli
. All 11 patients with urinary tract infections survived, irrespective of the MIC. For other sources, 30-day mortality was lower for isolates with a MIC of ≤2 mg/liter than for isolates with a higher MIC (0% versus 41.1%;
P
= 0.02).
Molecular Characterization of Acquired Enrofloxacin Resistance in Mycoplasma synoviae Field Isolates
Authors: Lysnyansky I. , Gerchman I. , Mikula I. , Gobbo F. , Catania S. , Levisohn S.
Published: April 2013

The
in vitro
activity of enrofloxacin against 73
Mycoplasma synoviae
field strains isolated in Israel and Europe was determined by broth microdilution. Decreased susceptibility to enrofloxacin was identified in 59% of strains, with the MICs ranging from 1 to >16 μg/ml. The estimated MIC
50
and MIC
90
values for enrofloxacin were 2 and 8 μg/ml, respectively. Moreover, this study showed that 92% of recent Israeli field isolates (2009 to 2011) of
M. synoviae
have MICs of ≥2 μg/ml to enrofloxacin. Comparison of the quinolone resistance-determining regions (QRDRs) in
M. synoviae
isolates revealed a clear correlation between the presence of one of the amino acid substitutions Asp79-Asn, Thr80-Ala/Ile, Ser81-Pro, and Asp84-Asn/Tyr/His of the ParC QRDR and decreased susceptibility to enrofloxacin (MIC, ≥1 μg/ml). Amino acid substitutions at positions GyrA 87, GyrB 401/402, and ParE 420/454 were also identified, but there was no clear-cut correlation with susceptibility to enrofloxacin. Comparison of
vlhA
molecular profiles revealed the presence of 9 different genotypes in the Israeli
M. synoviae
field isolates and 10 genotypes in the European isolates; only one
vlhA
genotype (type 4) was identified in both cohorts. Based on results of
vlhA
molecular typing, several mechanisms for emergence and dissemination of Israeli enrofloxacin-resistant
M. synoviae
isolates are suggested.
Effect of Mutations at Position E138 in HIV-1 Reverse Transcriptase and Their Interactions with the M184I Mutation on Defining Patterns of Resistance to Nonnucleoside Reverse Transcriptase Inhibitors Rilpivirine and Etravirine
Authors: Xu Hong-Tao , Colby-Germinario Susan P. , Asahchop Eugene L. , Oliveira Maureen , McCallum Matthew , Schader Susan M. , Han Yingshan , Quan Yudong , Sarafianos Stefan G. , Wainberg Mark A.
Published: April 2013

Impacts of mutations at position E138 (A/G/K/Q/R/V) alone or in combination with M184I in HIV-1 reverse transcriptase (RT) were investigated. We also determined why E138K is the most prevalent nonnucleoside reverse transcriptase inhibitor mutation in patients failing rilpivirine (RPV) therapy. Recombinant RT enzymes and viruses containing each of the above-mentioned mutations were generated, and drug susceptibility was assayed. Each of the E138A/G/K/Q/R mutations, alone or in combination with M184I, resulted in decreased susceptibility to RPV and etravirine (ETR). The maximum decrease in susceptibility to RPV was observed for E138/R/Q/G by both recombinant RT assay and cell-based assays. E138Q/R-containing enzymes and viruses also showed the most marked decrease in susceptibility to ETR by both assays. The addition of M184I to the E138 mutations did not significantly change the levels of diminution in drug susceptibility. These findings indicate that E138R caused the highest level of loss of susceptibility to both RPV and ETR, and, accordingly, E138R should be recognized as an ETR resistance-associated mutation. The E138K/Q/R mutations can compensate for M184I in regard to both enzymatic fitness and viral replication capacity. The favored emergence of E138K over other mutations at position E138, together with M184I, is not due to an advantage in either the level of drug resistance or viral replication capacity but may reflect the fact that E138R and E138Q require two distinct mutations to occur, one of which is a disfavorable G-to-C mutation, whereas E138K requires only a single favorable G-to-A hypermutation. Of course, other factors may also affect the concept of barrier to resistance.
Appropriateness of Empirical Treatment and Outcome in Bacteremia Caused by Extended-Spectrum-β-Lactamase-Producing Bacteria
Authors: Frakking Florine N. J. , Rottier Wouter C. , Dorigo-Zetsma J. Wendelien , van Hattem Jarne M. , van Hees Babette C. , Kluytmans Jan A. J. W. , Lutgens Suzanne P. M. , Prins Jan M. , Thijsen Steven F. T. , Verbon Annelies , Vlaminckx Bart J. M. , Cohen Stuart James W. , Leverstein-van Hall Maurine A. , Bonten Marc J. M.
Published: April 2013

We studied clinical characteristics, appropriateness of initial antibiotic treatment, and other factors associated with day 30 mortality in patients with bacteremia caused by extended-spectrum-β-lactamase (ESBL)-producing bacteria in eight Dutch hospitals. Retrospectively, information was collected from 232 consecutive patients with ESBL bacteremia (due to
Escherichia coli
,
Klebsiella pneumoniae
, and
Enterobacter cloacae
) between 2008 and 2010. In this cohort (median age of 65 years; 24 patients were <18 years of age), many had comorbidities, such as malignancy (34%) or recurrent urinary tract infection (UTI) (15%). One hundred forty episodes (60%) were nosocomial, 54 (23%) were otherwise health care associated, and 38 (16%) were community acquired. The most frequent sources of infection were UTI (42%) and intra-abdominal infection (28%). Appropriate therapy within 24 h after bacteremia onset was prescribed to 37% of all patients and to 54% of known ESBL carriers. The day 30 mortality rate was 20%. In a multivariable analysis, a Charlson comorbidity index of ≥3, an age of ≥75 years, intensive care unit (ICU) stay at bacteremia onset, a non-UTI bacteremia source, and presentation with severe sepsis, but not inappropriate therapy within <24 h (adjusted odds ratio [OR], 1.53; 95% confidence interval [CI], 0.68 to 3.45), were associated with day 30 mortality. Further assessment of confounding and a stratified analysis for patients with UTI and non-UTI origins of infection did not reveal a statistically significant effect of inappropriate therapy on day 30 mortality, and these results were insensitive to the possible misclassification of patients who had received β-lactam–β-lactamase inhibitor combinations or ceftazidime as initial treatment. In conclusion, ESBL bacteremia occurs mostly in patients with comorbidities requiring frequent hospitalization, and 84% of episodes were health care associated. Factors other than inappropriate therapy within <24 h determined day 30 mortality.
The Clinical Isolate Pseudomonas aeruginosa MMA83 Carries Two Copies of the
bla
NDM-1
Gene in a Novel Genetic Context
Authors: Jovčić Branko , Lepsanović Zorica , Begović Jelena , Rakonjac Bojan , Perovanović Jelena , Topisirović Ljubiša , Kojić Milan
Published: April 2013

The genetic context of the
bla
NDM-1
gene in the genome of
Pseudomonas aeruginosa
MMA83 was investigated. Sequencing of the cosmid selected for the
bla
NDM-1
gene revealed the presence of two
bla
NDM-1
copies in the genome of
P. aeruginosa
MMA83 in a unique genetic environment. Additionally, mating assays, DNA-DNA hybridization, and an S1 nuclease assay strongly suggest that the
bla
NDM-1
gene in
P. aeruginosa
MMA83 is chromosome borne.
Molecular Characterization of
bla
NDM-1
in a Sequence Type 235 Pseudomonas aeruginosa Isolate from France
Authors: Janvier Frédéric , Jeannot Katy , Tessé Sophie , Robert-Nicoud Marjorie , Delacour Hervé , Rapp Christophe , Mérens Audrey
Published: April 2013

An NDM-1 carbapenemase-producing
Pseudomonas aeruginosa
isolate was recovered from a patient hospitalized in France after a previous hospitalization in Serbia. Genetic studies revealed that the
bla
NDM-1
gene was surrounded by insertion sequence IS
Aba125
and a truncated bleomycin resistance gene. This
bla
NDM-1
region was a part of the variable region of a new complex class 1 integron bearing IS common region 1 (IS
CR1
). The presence of IS
Pa7
upstream of this integron suggests insertion in a chromosomally located Tn
402
-like structure.
Chapter 5.—Origin of the Mississippi Valley Lead and Zinc Deposits—A Critical Summary
Authors: Bastin Edson S. , Behre Chas. H.
Published: April 2013

INTRODUCTION

To trace fully and in chronological sequence the development of ideas concerning the origin of the lead and zinc ores of the Mississippi Valley region would be of considerable historic interest but a task of discouraging magnitude. It is fortunate, therefore, that the concepts of genesis, though varying much in detail, lend themselves to a grouping in two major categories: (1) The meteoric hypotheses, and (2) the magmatic hypothesis.

In the following summary chronology and the crediting of ideas to their ultimate source will be subordinated to simplicity and brevity of treatment.

As pointed out by Shepard (1898, p. 169–170), the earlier geologists, including Schoolcraft, Featherstonhaugh, Swallow, Owen, and Percival, being familiar mainly with the more steeply inclined vein-like occurrences, were almost unanimous in attributing the mineralization to ascending solutions from deep-seated sources. With the discovery and development of the great blanket deposits which gave little or no evidence of extension to considerable depths, the concept of leaching of the metals from sparse disseminations in the country rocks and concentration in their present location by meteoric waters became the dominant view and was presented in the reports of T. C. Chamberlin, Winslow, Bain, Van Hise, Buckley, Buehler, Grant, Siebenthal, Cox, and others. Shepard and Jenney were notable dissenters from this view. Of recent years, as a consequence of the mounting volume of evidence indicating that the majority of metalliferous deposits were deposited by solutions from magmatic sources and as a consequence of the discovery of numerous though scattered . . .
Chapter 2.—Structural Features of the Mississippi Valley Region and Their Relation to Mineralization
Authors: Giles Albert W.
Published: April 2013

INTRODUCTION

The Mississippi Valley is a large area of plains and low plateaus between the Appalachian Mountains on the east and the Cordilleras on the west. It is the southern part of the central stable region of North America. The basement rocks are pre-Cambrian crystallines whose surface is irregular and nearly everywhere buried beneath Paleozoic and later sediments. The ancient crystallines appear at the surface in the Sioux quartzite area of southwestern Minnesota, the Black Hills of western South Dakota, the Baraboo region of Wisconsin, the St. Francis Mountains of eastern Missouri, the Arbuckle Mountains of south-central Oklahoma, the Wichita Mountains of southwestern Oklahoma, and the Central Mineral Region of eastern Texas. In general, however, the thickness of the sedimentary cover is several thousand feet. In the eastern and central parts of the Mississippi Valley the surface rocks are of Paleozoic age, except where overlapped by Coastal Plain Cretaceous and Tertiary sediments. In the western part of the Valley, Cretaceous and Tertiary rocks cover large areas and overlie the older Paleozoic sediments. The Paleozoic sediments were derived mainly from five old landmasses—Laurentia on the north, Appalachia on the east, Llanoria on the south, Columbia on the southwest, and Cascadia on the west. Since their deposition the beds have been flexed into broad domes and basins which constitute the major structural elements of the Mississippi Valley. The deformation of most of the region has been so slight that regional dips of more than one degree are rare. Locally broad and . . .
Chapter 3.—Igneous Rocks of the Mississippi Valley Lead-Zinc Districts
Authors: Tolman Carl , Landes Kenneth K.
Published: April 2013

GENERAL STATEMENT

The igneous rocks of the Mississippi Valley lead-zinc district are widely distributed, but their total area of outcrop is relatively small (Fig. 13). They include exposed parts of the pre-Cambrian basement, almost wholly confined to the St. Francis Mountains adjacent to the southeastern Missouri lead-producing district, and small bodies which have intrusive contacts with sedimentary rocks of various horizons in the Paleozoic and in the Mesozoic as late as mid-Cretaceous. The rocks of the St. Francis Mountains occupy an area of several hundred square miles, but the other occurrences are so small that they must be indicated diagrammatically on all but very large scale maps. Nevertheless they are important components of the geological setting, and their careful consideration is warranted in order to bring out any possible genetic, structural, or other relationship that they may have to the lead-zinc mineralization.

The igneous rocks show a wide range in petrographic character, but it seems true, both among the pre-Cambrian and among the younger rocks, that they are preponderantly either basic or acidic with a meager development of intermediate types. Of exceptional petrographical interest are the alkalic varieties of Arkansas. The age of most of the igneous rocks younger than pre-Cambrian is indefinitely known, and there is difference of opinion as to whether more than one intrusive epoch is represented. An igneous history of some complexity is indicated in the pre-Cambrian rocks so that probably a considerable range of time in the pre-Cambrian is represented. However, since the pre-Cambrian intrusives . . .
Foreword
Authors: Bastin Edson S.
Published: April 2013

The Mississippi Valley region has long held the dominant position in the domestic production of both lead and zinc and has been an important factor in bringing the United States into a position of world leadership in the production of these metals. The situation of these deposits in a mid-continent region of continually growing industrial importance, their large areal extent, and prolonged productivity have made them the object of repeated study by State and Federal Geological surveys and by geologists and engineers employed by the mining companies, and an amazingly voluminous literature concerning them has accumulated in the course of nearly 50 years of intermittent investigation.

Almost from the beginning of such studies scientific opinion on the origin of the ores has wavered back and forth between the concept that the ore-depositing solutions emanated from deep-lying bodies of igneous magmas and the view that the metals were scattered in minute amounts through the country rocks and had been dissolved from them by meteoric waters and precipitated in concentrated form in the present ore bodies.

Not in the hope of settling this old and vexing problem but of hastening its eventual solution, these ore deposits became the object of special attention by the National Research Council through a subcommittee of its Committee on the Processes of Ore Deposition that was organized in 1932, and a number of papers that were partly stimulated by this committee’s activities have already been published. The committee felt that its official activities could appropriately be concluded . . .
Melting and Transformation Temperatures of Mineral and Allied Substances
Authors: Kracek F. C.
Published: April 2013

ContentsPageTable 111. Elements1422. Oxides1433. Hydrous and hydrated oxides1464. Binary aluminates1485. Binary borates1496. Binary oxide systems1507. Three or more oxides (except SiO2)1528. Binary silicates1539. Ternary and higher silicate systems15510. Aluminosilicates15811. Borosilicates16112. Miscellaneous systems containing silicates16113. Hydrothermal alteration of silicates and other minerals16214. Carbonates16315. Sulfates16416. Oxygen salts16617. Haloids16818. Sulfide-type minerals17019. Ternary sulfides173

Scope of the tables.—These tables list the melting (congruent and incongruent) temperatures, boiling temperatures, and transition temperatures for the more important substances of interest to the geologist, the geochemist, and the petrologist. Eutectic and related data are given when the substance under discussion has been studied as a part of a binary or higher system. The aim in compiling the tables has been to describe the known thermal reactions of the compounds and the systems briefly, but in enough detail to be of use to an investigator in the field where extensive reference books are usually not available.

Arrangement.—The entries are arranged alphabetically by chemical symbol (elements) or formula (compounds). Compounds composed of two or more oxides (except carbonates, sulfates, and other oxygen salts) are entered in the increasing alphabetical order of the constituent oxides.

Mineralogical names are given following the nomenclature employed in Dana-Ford : Textbook of mineralogy (John Wiley and Sons Inc., New York).
Effect of Pressure on Temperatures of Melting and of Solid-Solid Equilibrium, in Systems of One Component
Authors: Birch Francis
Published: April 2013

ContentsPageTable 121. Melting and solid-solid transitions of elements1771.1. Melting temperatures of A, H2, He, N2, Ne, and O21801.2. Formulas for melting curves1822. Melting and transitions of compounds1833. Liquid-vapor critical data185

In systems containing a single component, the change ΔT of the temperature of equilibrium between two phases resulting from a change of hydrostatic pressure ΔP upon the two phases is given by Clapeyron’s equation, ΔT/ΔP = TΔV/ΔH, where T is the absolute temperature, and ΔV and ΔH are the volume change and heat absorption, respectively, for a given mass of material in passing from one phase to the other. One phase may be considered the “high-temperature” phase, the other, the “low-temperature” phase. Heat is always absorbed in passing from the low-temperature phase to the high-temperature phase at constant pressure (the actual quantity may be negligibly small). In the same way, one of the phases will be the “low-pressure” phase, the other the “high-pressure” phase; in passing from the low-pressure phase to the high-pressure phase at constant temperature, the density always increases, or ΔV is negative. There is, however, no a priori way of knowing whether the high-temperature phase will be the high-pressure phase or the low-pressure phase. The liquid phase is “normally” the high-temperature, low-pressure phase with respect to solid phases; thus, in passing from a “normal” solid phase to the liquid phase, ΔV and ΔH are both positive, and ΔT/ΔP is positive (the melting temperature increases with . . .
Heat Capacity; Heat of Fusion
Authors: Goranson Roy W.
Published: April 2013

ContentsPageTable 161. Heat capacity of minerals2282. Heat capacity of rocks2353. Heats of transformation and of fusion2374. Heat capacity of gases241

Heat capacities of minerals.—In the tables (in this section), the minerals are classified according to the first elements of their chemical formulae; for example, albite (NaAlSi8O8) will be found under sodium, and calcite (CaCO3) under calcium. The heat data are given in terms of absolute joules per gram (one joule = 0.23895 gram calories at 15°C.).

True or instantaneous heat capacities may be obtained by measuring the amount of heat needed to raise the temperature of the sample one degree or fraction thereof. This is the preferable type of data, available for many materials at low temperatures. At high temperatures this method is experimentally difficult because of large radiation losses so that ordinarily a different technique is employed—namely, the method of mixtures. (See W. P. White, The Modern Calorimeter, N. Y., 1928.) This latter method yields data in the form of mean or interval heat capacities. The mean heat capacity is usually given for the temperature interval between 273.1°K. (0°C.) or room temperature and some higher temperature. The quantity measured is, however, the difference in heat content between some elevated temperature and that of the calorimeter. In order to convert these quantities to true heat capacities the mean heat capacity data (at constant pressure) are fitted to the equation 1c¯p|TTo=a+bTo+T2−cToTwhere c̄p is the mean heat capacity at . . .
Radioactivity: The Earth’s Heat and Geological Age Measurements
Authors: Evans Robley D. , Goodman Clark , Keevil Norman B.
Published: April 2013

ContentsPageTable 181. Heat flow to the earth’s surface2692. Radioactive content and heat generation in rocks2703. Ultimate products of naturally occurring disintegration processes2714. Isotopic constitution of radioactive elements and their end products2725. Variations in the isotopic composition of common lead2736. Lead age ratios of selected radioactive minerals2747. Age results by lead isotope ratios2758. Helium age ratios of various magnetite deposits276

THE EARTH’S HEAT

A. Loss of heat.—Only a limited amount of data is available on the heat flux transferred to the surface from within the earth. These observations are summarized in Table 18–1 and show a mean value of 1.3 ± 0.1 × 10−6 cal./cm.2/sec., when the necessary correction is made for the effect of the recent ice age. Considering the heat conductivity of the outer granitic layer as 0.006 cal./sec./cm.2/°C./cm., the corresponding surface geothermal gradient is about 2.0 × 10−4°C./cm., or 20°C./km.

This heat is partially transferred to the atmosphere by convection and radiation with subsequent reradiation by the atmosphere into space. The remainder of the heat is radiated directly through the blanketing atmosphere. The proportion of heat loss attributable to each of these processes is still a matter of speculation.

B. Sources of heat.—Aside from the residuum of heat associated with the earth at the time of its formation, the primary sources of heat in the earth are radioactivity, solar radiation, and exothermal chemical changes.

1. Radioactivity: Because . . .
Electrical Properties of Rocks and Minerals
Authors: Slichter Louis B. , Telkes M.
Published: April 2013

ContentsPageTable 211. Electrical resistivity of rocks and soils3042.1. Electrical resistivity of mineralized rocks3072.2. Electrical resistivity of specular hematite in quartz porphyry3073. Electrical resistivity of metallic sulfides3084. Electrical resistivity of some oxides and miscellaneous minerals3115. Electrical resistivity of hydrocarbons3136.1. Electrical resistivity of natural water3146.2. Electrical resistivity of saline waters3146.3. Effect of water and oil on direct current resistance of sandstone3156.4. Electrical resistivity of wet sand3156.5. Resistivity of soils and sea water measured with high-frequency alternating current3167. Dielectric constant of rocks3178. Dielectric constant of minerals3188.1. Dielectric constant of Rochelle salt, as function of temperature318

ELECTRICAL RESISTIVITY

(1) Electrolytic conductors.—The electrical conductivity of rocks and soils in place is generally due almost entirely to the moisture content. With some exceptions, the solid minerals which constitute the rock or soil are good insulators. Thus, the conductivity is not an essential property of the rock or rock type; it depends not only upon the capacity of the rock to absorb water and upon the kind and structure of its pore spaces, but also upon the amount and composition of the water retained. Hence, the conductivity may depend to an important extent upon the accident of the geological and climatic environment in which the material happens to find itself. It follows that resistivities tabulated in the literature should not be used to predict the . . .
Density at High Pressure; Compressibility
Authors: Birch Francis
Published: April 2013

ContentsPageTable 41. Compressibility of elements crystallizing in the cubic system432. Compressibility of elements crystallizing in the hexagonal and tetragonal systems463. Compression of a few miscellaneous elements474. Compression and thermal expansion of the alkali metals484.1. Effect of pressure on thermal expansion485. Compression of elements to 50,000 kg/cm2496. Compression of compounds to 50,000 kg/cm2507. Compressibility of cubic compounds528. Compressibility of hexagonal, trigonal, and tetragonal compounds549. Compressibility of orthorhombic compounds5610. Compressibility of monoclinic and triclinic compounds5811. Change of compressibility on melting5912. Compressibility of several artificial and natural glasses6013. Compressibility of rocks at low pressures6114. Compressibility of rocks at high pressures62

Density and specific volume are dependent not only upon the temperature but also upon the stress. A stress system consisting of uniform pressure in all directions is known as “ hydrostatic” pressure; the change of specific volume or of density for not too great changes of hydrostatic pressure may be described in terms of a single coefficient, the compressibility β, defined by β=1V0(dVdP)T=1ρ0(dρdP)T, where V0 is the specific volume, ρ0 the density at 1 atmosphere, and P the pressure. Since dV/dP is intrinsically negative, β is a positive number, with the dimensions of the reciprocal of a pressure or stress. In general, β depends upon the pressure and the temperature. Its reciprocal K is known as the bulk modulus.

The compressibility . . .
Density at Room Temperature and 1 Atmosphere
Authors: Berman H. , Daly R. A. , Spicer H. C.
Published: April 2013

ContentsPageTable 21. Density of minerals (H. Berman)82. Average densities of holocrystalline igneous rocks (R. A. Daly)143. Densities of crystals and corresponding glasses (R. A. Daly)154. Density of natural glasses (R. A. Daly)165. Density of crystalline rock and corresponding glass (artificially prepared) (R. A. Daly)166. Porosity and bulk density, dry and saturated, of sedimentary deposits (H. C. Spicer)177. Loss of weight on drying at elevated temperatures (H. C. Spicer)26

Table 2 – 1.—Density of Minerals

(H. Berman)

The densities of minerals here listed are selected from the complete list by Rosenholtz and Smith, Rensselaer Polytechnic Institute Eng. and Sci. Series, No. 34, Troy, 1931, who have compiled all the published values. The ranges given are, in most cases, not significant, since they arise from an uncritical compilation of the limiting values found in the literature. Some minerals have a considerable spread in specific gravity as a result of isomorphous substitution, and in these instances it is necessary to correlate a specific chemical analysis with the given value of density. In a number of instances, new values marked * have been substituted for those in Rosenholtz and Smith.

Room temperature, 1 atm. NameDensity gm./cm.3NameDensity gm./cm.3Acanthite7.2 – 7.33Annite2.8 – 3.4Actinolite2.9 – 3.2Anorthite2.70 – 2.76Adamite4.34 – 4.35Anorthite, pure2.76Adularia2.56Anorthoclase2.56 – 2.65Aegirinaugite3.5Anthophyllite2.86 – 3.2Aegirite3.5 – 3.56Antigorite2.55 – 2.62Aegirite-hedenbergite3.502* Antimony
Internal Friction in Vibrating Solids
Authors: Birch Francis
Published: April 2013

ContentsPageTable 61. Internal friction in single crystals892. Internal friction in polycrystalline metals903. Internal friction in glass914. Internal friction in rocks92

The vibrations of solid bodies are accompanied by dissipation of energy attributable to their “ internal friction”; this loss of energy is additional to whatever external losses may occur. There are various ways of specifying the internal friction, and few of the published researches have adopted a common terminology. In this section the results have been reduced to show a dimensionless quantity, 1/Q, which may be called the “dissipation function” or the “internal friction.” The logarithmic decrement Δ of free vibrations is related to this function by Δ = π/Q. If dE is the loss of energy per cycle, and E the total energy, then 1/Q = dE/(2πE), Thus the internal friction is small when 1/Q is small.

Only in the last few years has the technique of measuring internal friction reached a point where the losses in single crystals can be studied [4, 16, 17]. The mechanism of internal dissipation of energy in single crystals probably involves plastic flow and strain hardening even for very small strains. The internal friction is sensitive to the condition of the surface and to annealing [16]. Unannealed single crystals may show losses approaching those of polycrystalline material. In the latter, internal friction arises from a number of distinct sources, including (1) losses within the individual crystals, (2) losses at the surfaces of the . . .
Seismic Velocities
Authors: Leet L. D. , Birch Francis
Published: April 2013

ContentsPageTable 71. Field determinations of wave velocities at small depths952. Velocity of compressional waves in soils, water, petroleum963. Velocity in relation to depth and age974. Seismic velocities and thickness of upper layers in various regions995. Seismic velocities in the interior of the earth101

Seismic prospecting or surveying constitutes one of the most important geophysical diagnostic methods; knowledge of the wave velocities in different materials is evidently a primary requirement, to which a great deal of effort has been devoted in the field and laboratory. Unfortunately for the sensitivity of the diagnosis, a given material is not characterized by a unique set of velocities, different from those of all other materials. For each material, the velocities depend upon a number of factors, such as alteration, present and perhaps former depth, and in some cases moisture, direction with respect to schistosity, bedding, and so on. Thus a range of values must exist even for a fairly well defined material, and this range frequently overlaps, to a large extent, the ranges of other materials. A velocity determined in the field for a more or less well-defined formation will represent an average for the varying conditions within this layer along the path of the wave; for different depths of penetration, different conditions and hence different velocities may be expected. The determinations which have been published are not adequate for the formulation of definite relations between velocity and the various other factors except . . .
25-Year summary of US malpractice claims for diagnostic errors 1986–2010: an analysis from the National Practitioner Data Bank
Authors: Saber Tehrani Ali S , Lee HeeWon , Mathews Simon C , Shore Andrew , Makary Martin A , Pronovost Peter J , Newman-Toker David E
Published: April 2013

Background

We sought to characterise the frequency, health outcomes and economic consequences of diagnostic errors in the USA through analysis of closed, paid malpractice claims.

Methods

We analysed diagnosis-related claims from the National Practitioner Data Bank (1986–2010). We describe error type, outcome severity and payments (in 2011 US dollars), comparing diagnostic errors to other malpractice allegation groups and inpatient to outpatient within diagnostic errors.

Results

We analysed 350 706 paid claims. Diagnostic errors (n=100 249) were the leading type (28.6%) and accounted for the highest proportion of total payments (35.2%). The most frequent outcomes were death, significant permanent injury, major permanent injury and minor permanent injury. Diagnostic errors more often resulted in death than other allegation groups (40.9% vs 23.9%, p<0.001) and were the leading cause of claims-associated death and disability. More diagnostic error claims were outpatient than inpatient (68.8% vs 31.2%, p<0.001), but inpatient diagnostic errors were more likely to be lethal (48.4% vs 36.9%, p<0.001). The inflation-adjusted, 25-year sum of diagnosis-related payments was US$38.8 billion (mean per-claim payout US$386 849; median US$213 250; IQR US$74 545–484 500). Per-claim payments for permanent, serious morbidity that was ‘quadriplegic, brain damage, lifelong care’ (4.5%; mean US$808 591; median US$564 300), ‘major’ (13.3%; mean US$568 599; median US$355 350), or ‘significant’ (16.9%; mean US$419 711; median US$269 255) exceeded those where the outcome was death (40.9%; mean US$390 186; median US$251 745).

Conclusions

Among malpractice claims, diagnostic errors appear to be the most common, most costly and most dangerous of medical mistakes. We found roughly equal numbers of lethal and non-lethal errors in our analysis, suggesting that the public health burden of diagnostic errors could be twice that previously estimated. Healthcare stakeholders should consider diagnostic safety a critical health policy issue.
AN OPINION SPREADING MODEL IN SIGNED NETWORKS
Authors: LI WEI , FAN PENGYI , LI PEI , WANG HUI , PAN YIGUANG
Published: April 2013

The opinion spreading process can be modeled as the spread of an epidemic through a network, which assumes homogeneous relationships between individuals. However, positive and negative relationships in signed networks play different roles in the opinion spreading process, following the general rule that the same opinion will diffuse through friends, while the opposite opinion will likely emerge out of interactions between enemies. In order to explore opinion spreading behavior in signed networks, we proposed a simple opinion spreading model based on the susceptible-infected-recovered (SIR) epidemic model. Under the assumption of homogeneous mixing, we also analyzed the phase transition of opinion spreading in signed networks and found that critical spreading rates were closely related to the fraction of positive relationships in signed networks. Finally, we confirmed the correctness of our solutions using numerical simulations of the opinion spreading model in signed networks.
ENVELOPING ALGEBRAS OF PRELIE ALGEBRAS, SOLOMON IDEMPOTENTS AND THE MAGNUS FORMULA
Authors: CHAPOTON FRÉDÉRIC , PATRAS FRÉDÉRIC
Published: April 2013

We study the internal structure of enveloping algebras of preLie algebras. We show in particular that the canonical projections arising from the Poincaré–Birkhoff–Witt theorem can be computed explicitly. They happen to be closely related to the Magnus formula for matrix differential equations. Indeed, we show that the Magnus formula provides a way to compute the canonical projection on the preLie algebra. Conversely, our results provide new insights on classical problems in the theory of differential equations and on recent advances in their combinatorial understanding.