bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of abemaciclib in treatment of advanced breast cancer
Authors: McCartney Amelia , Moretti Erica , Sanna Giuseppina , Pestrin Marta , Risi Emanuela , Malorni Luca , Biganzoli Laura , Di Leo Angelo
Published: May 2018

Until recently, the mainstay of treatment in the majority of hormone receptor (HR)-positive, human epidermal growth factor 2 receptor (HER2)-negative advanced breast cancer (ABC) has consisted of single-agent endocrine therapy (ET). However, as understanding of endocrine resistance has grown, newer targeted agents have come to the fore. Inhibition of cyclin-dependent kinase complexes 4 and 6 (CDK4/6) combined with ET has shown significant activity in HR+ HER2− ABC, with impressive results in terms of progression-free survival (PFS) when compared with ET alone. This review summarizes the seminal findings pertaining to CDK4/6 inhibition in this population, specifically focusing on abemaciclib, contrasted with palbociclib and ribociclib. Potential directions for future studies are discussed, as a way of addressing outstanding issues such as establishing optimal treatment sequencing and agent combinations, appropriate patient selection to derive maximal benefits, predictive biomarkers and the employment of CDK4/6 inhibition beyond the ABC setting.
Use of Blood Glucose Meters Featuring Color Range Indicators Improves Glycemic Control in Patients With Diabetes in Comparison to Blood Glucose Meters Without Color (ACCENTS Study)
Authors: Grady Mike , Katz Laurence B. , Levy Brian L.
Published: May 2018

Background:

The ability of patients to improve glycemic control depends partly on their ability to interpret and act on blood glucose results. We investigated whether switching people with diabetes to blood glucose meters (BGMs) featuring a color range indicator (CRI) could improve glycemic control compared to remaining on their current BGM without color.

Methods:

163 adults with type 1 (T1D) or type 2 diabetes (T2D) and a hemoglobin A1c (A1c) of 7.5-11% were randomized to: One Touch Verio™ (Verio), OneTouch Verio Flex™ (Flex), or controls remaining on their current BGM. Diabetes nurses had standard conversations about diabetes management with all subjects at baseline. No changes in medication, insulin dosing, or SMBG frequency were recommended.

Results:

After 12 weeks, subjects who switched to Verio or Flex meters with CRI (n = 108) had a mean change in A1c 0.36% lower than controls (n = 55) ( P = .017). A1c reductions were greatest in T1D subjects (n = 45), with a decrease of 0.50% ( P = .004). T1D subjects using Verio meters (n = 25) contributed a 0.59% reduction compared to controls ( P < .008), whereas T1D subjects using Flex meters (n = 20) had a clinical meaningful reduction in A1c of 0.40% without reaching statistical significance ( P > .05). Verio and Flex users reported taking more action and easier understanding of diabetes management compared to previous BGMs.

Conclusions:

This study demonstrated that switching patients to BGMs featuring a CRI resulted in improvements in glycemic control compared to subjects using currently marketed BGMs that do not use a CRI. Registration: Clinicaltrials.gov NCT02929654 https://clinicaltrials.gov/ct2/show/NCT02929654
In Silico Assessment of Literature Insulin Bolus Calculation Methods Accounting for Glucose Rate of Change
Authors: Cappon Giacomo , Marturano Francesca , Vettoretti Martina , Facchinetti Andrea , Sparacino Giovanni
Published: May 2018

Background:

The standard formula (SF) used in bolus calculators (BCs) determines meal insulin bolus using “static” measurement of blood glucose concentration (BG) obtained by self-monitoring of blood glucose (SMBG) fingerprick device. Some methods have been proposed to improve efficacy of SF using “dynamic” information provided by continuous glucose monitoring (CGM), and, in particular, glucose rate of change (ROC). This article compares, in silico and in an ideal framework limiting the exposition to possibly confounding factors (such as CGM noise), the performance of three popular techniques devised for such a scope, that is, the methods of Buckingham et al (BU), Scheiner (SC), and Pettus and Edelman (PE).

Method:

Using the UVa/Padova Type 1 diabetes simulator we generated data of 100 virtual subjects in noise-free, single-meal scenarios having different preprandial BG and ROC values. Meal insulin bolus was computed using SF, BU, SC, and PE. Performance was assessed with the blood glucose risk index (BGRI) on the 9 hours after meal.

Results:

On average, BU, SC, and PE improve BGRI compared to SF. When BG is rapidly decreasing, PE obtains the best performance. In the other ROC scenarios, none of the considered methods prevails in all the preprandial BG conditions tested.

Conclusion:

Our study showed that, at least in the considered ideal framework, none of the methods to correct SF according to ROC is globally better than the others. Critical analysis of the results also suggests that further investigations are needed to develop more effective formulas to account for ROC information in BCs.
Seed Longevity of Five Tropical Species From South-Eastern Mexico: Changes in Seed Germination During Storage
Authors: Becerra-Vázquez Ángel G. , Sánchez-Nieto Sobeida , Coates Rosamond , Flores-Ortiz César M. , Orozco-Segovia Alma
Published: May 2018

To design conservation strategies, the extent of plant richness of tropical forests needs to be characterized in terms of their seed longevity. In this study, we examined the potential seed longevity, that is, storage ex situ, of species from south-eastern Mexico: Chamaedorea glaucifolia, Cymbopetalum baillonii, Magnolia mexicana, Nectandra coriacea, and Ternstroemia tepezapote. Immediately after collection, seeds were stored at different temperatures (≤23℃). We evaluated seed germination after different storage durations. Seed water content (WC) was determined for each period. Seed desiccation sensitivity was determined as WC50, which is the WC at which the initial seed viability decreases to 50%; further, the time required to reach WC50 was also determined. Subsequently, we analyzed the relations between seed functional traits with other morphological and functional traits, along with the weather characteristics of their respective habitat. All of the studied species had short-lived seeds; they exhibited desiccation sensitivity after storage with differences across the species. Additionally, C. baillonii exhibited differences in seed desiccation sensitivity across 2 years of seed collection. Interaction was observed between storage time and storage temperature: Seeds exhibited less deterioration at 15℃ in C. glaucifolia and C. baillonii and at 5℃ in M. mexicana and N. coriacea. Seed storage behavior is discussed in this article. Finally, a relationship determined between germination traits, and seed WC, embryo size, endosperm amount, and rain and temperature patterns in the month of seed dispersal explained the limited longevity of the studied species.
School-Wide Foresight Education: All Together Now!
Authors: Shostak Arthur B.
Published: May 2018

Schools are better when futures studies are included in the curriculum. This is not common today but can become common with creative and persistent effort. A plan is offered for systematic and sustained promotion in the nation’s K–12 school system. Examples are provided of projects for age appropriate employ throughout K–12 schooling.
Nasal septal abscess as a sequela of orbital cellulitis: An uncommon presentation
Authors: Fatima Syeda Nidaa , Sarwar Fatima , Khan Muhammad Sarwar
Published: May 2018

Nasal septal abscess is a rather unusual condition encountered in the Otorhinolaryngology outpatient department, let alone it being a complication of orbital cellulitis! The condition usually occurs due to trauma which is significant enough to cause a septal haematoma. The haematoma then eventually results in formation of a localised abscess. Orbital cellulitis as a sequela of nasal septal abscess is an established complication but vice versa, septal abscess as a sequela of orbital cellulitis is an extremely rare presentation. To emphasise the possibility of anterograde as well as retrograde passage of infection via valveless veins in the face, we report a unique case of a 2-month-old infant who developed nasal septal abscess as a complication of orbital cellulitis.
Sarcopenia is associated with reduced survival in patients with advanced hepatocellular carcinoma undergoing sorafenib treatment
Authors: Antonelli Giulio , Gigante Elia , Iavarone Massimo , Begini Paola , Sangiovanni Angelo , Iannicelli Elsa , Biondetti Piero , Pellicelli Adriano M. , Miglioresi Lucia , Marchetti Paolo , Lampertico Pietro , Marignani Massimo
Published: May 2018

Background

Sarcopenia has been associated with poor outcomes in patients with cirrhosis and solid tumours.

Objective

Analyse the influence of sarcopenia on survival and treatment duration in patients with advanced hepatocellular carcinoma (HCC) treated with sorafenib.

Methods

We conducted a multicentre, retrospective study on 96 patients with advanced HCC treated with sorafenib, all with available abdominal computed tomography (CT) scan within 30 days from treatment start. Anthropometric, laboratory, treatment and follow‐up data were collected. Sarcopenia was defined by reduced skeletal muscle index calculated from an L3 section CT image.

Results

Sarcopenia was present in 49% of patients. Patients were divided into two groups according to sarcopenia: age was significantly higher in the sarcopenic group (SG) (66 years (31–87) versus 72 years (30–84), p = 0.04], with no difference in other baseline characteristics. The SG showed shorter overall survival (OS) (39 (95% confidence interval (CI) 26–50) versus 61 (95% CI 47–77) weeks (p = 0,01)) and shorter time on treatment (12.3 (95% CI 8–19) versus 25.9 (95% CI 15–33) weeks (p = 0.0044)). At multivariate analysis, sarcopenia was independently associated to reduced OS (p = 0.03) and reduced time on treatment (p = 0.001).

Conclusion

Sarcopenia is present in almost half of patients with advanced HCC, and is associated with reduced survival and reduced duration of oral chemotherapy.
Developing programme theories as part of a realist evaluation of a healthcare quality improvement programme
Authors: Feather Julie Louise
Published: May 2018

The application of realist approaches to health services research and evaluation has continued to grow over the past two decades. However, difficulties in defining and operationalising key realist concepts of contexts, mechanisms and outcomes in healthcare settings continue to be recognised within the realist evaluation literature. Reflecting on an ongoing realist evaluation of a healthcare quality improvement programme across an inter-organisational context, this article explores some of the methodological challenges encountered by the author in the early stages of programme theory development. An individualised operationalisation and application of realist concepts are presented to demonstrate how initial programme theories can be developed despite the methodological difficulties presented.
Staphylococcus-Associated Glomerulonephritis Mimicking Henoch-Schönlein Purpura and Cryoglobulinemic Vasculitis in a Patient With an Epidural Abscess: A Case Report and Brief Review of the Literature
Authors: Mahmood Tahrin , Puckrin Robert , Sugar Linda , Naimark David
Published: May 2018

Rationale:

Staphylococcus-associated glomerulonephritis (SAGN) is a rare immune complex–mediated glomerulonephritis associated with active Staphylococcus infection. We report a case illustrating the importance of clinical history and kidney biopsy findings in establishing the correct diagnosis.

Presenting concerns of the patient:

We report the case of a 64-year-old man with alcohol-associated cirrhosis, type 2 diabetes mellitus, and hypertension who presented to hospital with lower back and abdominal pain, rectal bleeding, a purpuric lower extremity rash, and oliguric acute kidney injury with microscopic hematuria and nephrotic-range proteinuria.

Diagnoses:

Skin biopsy revealed IgA leukocytoclastic vasculitis. Serum cryoglobulins were positive and there was hypocomplementemia with a low C3 level. Magnetic resonance imaging of the lumbar spine revealed septic discitis and epidural abscesses caused by a recent Staphylococcus aureus bacteremia. Kidney biopsy showed IgA-dominant and C3-dominant proliferative glomerulonephritis with subepithelial humps in keeping with SAGN.

Interventions:

Urgent hemodialysis was initiated along with a prolonged course of intravenous cefazolin.

Outcomes:

Remarkably, the patient demonstrated a complete recovery of renal function after 2 months of dialysis dependence and successful treatment of the epidural abscesses.

Lessons learned:

This case shows that SAGN can closely mimic the clinical, laboratory, and histological presentation of Henoch-Schönlein Purpura or cryoglobulinemic vasculitis. Clinical history and kidney biopsy, particularly electron microscopic analysis, are essential to establishing the correct diagnosis to avoid the unnecessary and potentially harmful administration of immunosuppression. Despite the typically poor prognosis of SAGN, this case report illustrates that full renal recovery remains possible with supportive care and eradication of the underlying infection.
Two Brothers With Dextro-Transposition of the Great Arteries
Authors: Kurtz Joshua D. , Boucek Katerina , Kavarana Minoo , Atz Andrew M.
Published: May 2018

Dextro-transposition of the great arteries (d-TGA) is a common cause of cyanotic heart disease in neonates. Current thought is d-TGA is a sporadic occurrence in families with an unclear etiology. We describe a case of brothers with d-TGA. Genetic testing revealed that both are heterozygous for two gene variations that are associated with congenital heart disease.
Motor Clusters Reveal Differences in Risk for Psychosis, Cognitive Functioning, and Thalamocortical Connectivity: Evidence for Vulnerability Subtypes
Authors: Dean Derek J. , Walther Sebastian , Bernard Jessica A. , Mittal Vijay A.
Published: May 2018

Abnormal development of parallel cortical-striatal networks may contribute to abnormal motor, cognitive, and affective behavior prior to the onset of psychosis. Partitioning individuals at clinical high risk (CHR) using motor behavior may provide a novel perspective on different etiological pathways or patient subtypes. A k-means cluster analysis was conducted in CHR ( N = 69; 42% female, mean age = 18.67 years) young adults using theoretically distinct measures of motor behavior. The resulting subtypes were then compared on positive and negative symptoms at baseline, and 2-year risk of psychosis conversion. CHR participants were followed for 2 years to determine conversion to psychosis. CHR subtypes and healthy controls ( n = 61; 57% female, mean age = 18.58 years) were compared on multiple cognitive domains and cortical-striatal connectivity. Results suggest 3 vulnerability subtypes of CHR individuals with different profiles of motor performance, symptoms, risk for conversion to psychosis, cognition, and thalamocortical connectivity. This approach may reflect a novel strategy for promoting tailored risk assessment as well as future research developing individualized medicine.
The Case Method in Legal Education
Authors: Dhar Upinder , Dhar Santosh
Published: May 2018

Each doctrine has a history. In the case of law, Langdell has argued that students would be better educated if they were asked to draw their own conclusions about the meaning of judicial decisions. Case studies provide students with an overview of the main issue; background of the institution, industry and individuals involved; and the events that had led to the problem or decision. Faculty may assign questions prior to class to facilitate the students to focus on certain important issues. Principles of law are taught by making the students analyse abridgments of appellate cases in combination with the Socratic method.
Application of Data Mining to a Large Hearing-Aid Manufacturer’s Dataset to Identify Possible Benefits for Clinicians, Manufacturers, and Users
Authors: Mellor Joseph , Stone Michael A. , Keane John
Published: May 2018

Modern hearing instruments contain logging technology to record data, such as the acoustic environments in which the device is being used and how the signal processing is consequently operating. Combined with patient data, such as the audiogram, this information gives a more comprehensive picture of the user and their relationship with the aid. Here, a relatively large, anonymized dataset (>300,000 devices, >150,000 wearers) from a hearing-aid manufacturer was data mined for connections between subsets of the logged varieties of data. Apart from replicating links that have previously been reported in labor-intensive studies, a link between device style (in-the-ear/behind-the-ear) and the sound levels of encountered environments was demonstrated, suggesting that some device types are more successful from a lifestyle perspective. Furthermore, the data also suggested links between the audiogram and the sound environments in which the aid was operated. Modeling the expected link between the environment and the microphone directionality settings revealed patterns of either abnormal fitting or where the aid was not operating correctly—factors that may indicate a failed fitting. Given the necessarily redacted nature of the dataset, the reported findings represent a proof-of-concept of the use of relatively large-scale data mining to guide and assess hearing-aid fitting procedures for possible benefits to the clinician, manufacturer, and patient.
Driving and Patients With Dementia
Authors: Hamdy R. C. , Kinser A. , Kendall-Wilson T. , Depelteau A. , Whalen K. , Culp J.
Published: May 2018

Driving is a symbol of autonomy and independence, eagerly awaited during adolescence, cherished during adulthood and reluctantly rescinded during old age. It is nevertheless an individual’s privilege, not right, especially as driving may affect other drivers and pedestrians on the road. It is therefore not only the individual patient who is at stake but essentially the entire community. In this case scenario, we describe the situation that arose when a patient with multi-infarct dementia wanted to go for a drive and his son and grandson tried to convince him that he could no longer drive. What went wrong in the caregivers/patient interaction is presented. The futility of arguing with patients who have dementia is highlighted as well as the suspiciousness it may generate. Alternate actions that can be useful to avoid/avert the situation from escalating and having a catastrophic ending are discussed. Testing/evaluating patients with dementia for fitness to drive is also reviewed and a list of select resources is included.
Conceptualizing a Resilient Supply Chain for Single-fuel Biomass Power Plant
Authors: Bhaskar Kalyan , Jain Nikunj Kumar
Published: May 2018

India is taking several steps to decarbonize electricity as part of the climate change mitigation efforts. One of those steps has been to promote electricity generation from biomass. Past research has focused on risks related to technology, cost, financing, policy, and supply chain in case of biomass power, but there have been limited studies on risks arising due to climate change. Climate change can have major implications for the supply chain of biomass power plants by affecting the underground water availability and land productivity and thereby affecting the availability of biomass for power plants. The effect could be more acute for single-fuel biomass power plants rather than for multi-fuel biomass power plants. Using data from an 8 megawatt (MW) biomass power plant and by developing a conceptual model, this article models risks arising due to climate change and assesses their likely impact on single-fuel biomass power plants. Two key insights emerge from the analysis: (a) A supply chain that is not sustainable and resilient to climate change impacts poses a major risk to the profits of a biomass power plant; and (b) Single-fuel biomass power plants may need to change their businesses and sourcing strategies by either turning into multi-fuel biomass power plant or by increasing the catchment area of their sourcing.
Interpretive Structural Modeling-based Framework for Analysis of Sustainable Supply Chain Management Enablers: Indian Thermal Power Plant Perspective
Authors: Biswal Jitendra Narayan , Muduli Kamalakanta , Satapathy Suchismita , Yadav Devendra K. , Pumwa John
Published: May 2018

Indian thermal power industries, being perceived as the most polluting, are experiencing tremendous pressure to implement sustainable supply chain practices. In this light, the purpose of this article is to explore the factors that initiate sustainable supply chain management (SSCM) adoption in Indian thermal power industries and understand the interrelationship existing among them. Interpretive structural modeling (ISM) technique is employed to extract the structural relationship existing among the SSCM enablers and portray the same through a hierarchical model. Further, MICMAC (Matrice d’Impacts Croisés Multiplication Appliquée á un Classement) analysis has been employed to classify the enablers by taking their driving and dependence power as a measure. Eleven SSCM enablers have been explored through an extensive review of the literature. The interpretive structural model of selected enablers indicates that SSCM adoption in thermal power plants is mainly due to “pressure from environmental advocacy groups” and “government policies and employee pressure”. Prior knowledge of these influential factors and their interdependence will help the decision makers to develop suitable strategies that would enable the organizations to reduce the impact of barriers while optimizing the benefits derived from the enablers.
Human Resource Strategies for Operational Planning: Case Study of Tea Plantation Workers in India
Authors: Gupta Ananda Das
Published: May 2018

The concept of sustainability comes from considering the context of the organization. Leadership sustainability is not just what the leader does but how others are impacted by the leader’s actions. We judge ourselves by our intentions, but others judge us by our behaviors. It is imperative that the human resource development (HRD) perspectives along with human rights initiatives (HRI) in the plantation sector are of utmost importance in the direction of workers’ participation in management, their promotional scopes, the welfare measures, and the fatigue study to enhancing productivity. The role of government and the positive attitude of corporate sector are to be initiated in tandem for ushering their sector into a new dimension, which is but compulsory and nevertheless challenging.
The Ongoing Genocidal Crisis of the Rohingya Minority in Myanmar
Authors: Dussich John P. J.
Published: May 2018

The serious plight of the Rohingya ethnic group’s extreme victimization in Myanmar has finally emerged on the international stage. They are mostly a stateless Muslim minority from the state of Rakhine which, over recent decades, have been abused by severe and repeated multiple human rights violations. There are now approximately 850,000 displaced Rohingya refugees mostly in Bangladesh and surrounding countries with thousands more waiting in peril between Myanmar and Bangladesh. The saga of the Rohingya dilemma has been fraught with complex ethno-religious conflicts between Buddhist, Muslim and Hindu factions exacerbated by the scale of people involved, rapidity of events, recency of occurrences, abject poverty, racial hatred, linguistic differences, confused ancestral rights, severe humanitarian violations, genocidal policies, surrounded by nations themselves struggling with few resources. The present-day conflicted leadership in Myanmar between the military and the democratically elected leader of her government, Aung San Suu Kyi, has been severely criticized for their brutal continued ethnic cleansing.
Shear-induced integrin signaling in platelet phosphatidylserine exposure, microvesicle release, and coagulation
Authors: Pang Aiming , Cui Yujie , Chen Yunfeng , Cheng Ni , Delaney M. Keegan , Gu Minyi , Stojanovic-Terpo Aleksandra , Zhu Cheng , Du Xiaoping
Published: May 2018

Key Points

Shear-induced, Gα13-mediated integrin outside-in signaling facilitates platelet PS exposure, MV release, and coagulation. An inhibitor of outside-in signaling inhibits not only occlusive platelet thrombus formation but also intravascular coagulation in vivo.
Hematopoiesis and the bacterial microbiome
Authors: Yan Hannah , Baldridge Megan T. , King Katherine Y.
Published: May 2018

Recent studies have revealed that the intestinal bacterial microbiome plays an important role in the regulation of hematopoiesis. A correlation between adverse hematologic effects and imbalance of the intestinal microbiome, or dysbiosis, is evident in several human conditions, such as inflammatory bowel disease, obesity, and, critically, in the setting of antibiotic exposure. Here we review the effects of gut dysbiosis on the hematological compartment and our current understanding of the mechanisms through which changes in the bacterial microbiome affect hematopoiesis.
Similar telomere attrition rates in androgen-treated and untreated patients with dyskeratosis congenita
Authors: Khincha Payal P. , Bertuch Alison A. , Gadalla Shahinaz M. , Giri Neelam , Alter Blanche P. , Savage Sharon A.
Published: May 2018

Key Points

TL for age shortens over time in patients with the TBD DC, irrespective of treatment with androgens. Prospective long-term research is needed to understand the extra-hematopoietic effects of androgens for management of TBDs.
Measuring financial protection against catastrophic health expenditures: methodological challenges for global monitoring
Authors: Hsu Justine , Flores Gabriela , Evans David , Mills Anne , Hanson Kara
Published: May 2018

Background

Monitoring financial protection against catastrophic health expenditures is important to understand how health financing arrangements in a country protect its population against high costs associated with accessing health services. While catastrophic health expenditures are generally defined to be when household expenditures for health exceed a given threshold of household resources, there is no gold standard with several methods applied to define the threshold and household resources. These different approaches to constructing the indicator might give different pictures of a country’s progress towards financial protection. In order for monitoring to effectively provide policy insight, it is critical to understand the sensitivity of measurement to these choices.

Methods

This paper examines the impact of varying two methodological choices by analysing household expenditure data from a sample of 47 countries. We assess sensitivity of cross-country comparisons to a range of thresholds by testing for restricted dominance. We further assess sensitivity of comparisons to different methods for defining household resources (i.e. total expenditure, non-food expenditure and non-subsistence expenditure) by conducting correlation tests of country rankings.

Results

We found country rankings are robust to the choice of threshold in a tenth to a quarter of comparisons within the 5–85% threshold range and this increases to half of comparisons if the threshold is restricted to 5–40%, following those commonly used in the literature. Furthermore, correlations of country rankings using different methods to define household resources were moderate to high; thus, this choice makes less difference from a measurement perspective than from an ethical perspective as different definitions of available household resources reflect varying concerns for equity.

Conclusions

Interpreting comparisons from global monitoring based on a single threshold should be done with caution as these may not provide reliable insight into relative country progress. We therefore recommend financial protection against catastrophic health expenditures be measured across a range of thresholds using a catastrophic incidence curve as shown in this paper. We further recommend evaluating financial protection in relation to a country’s health financing system arrangements in order to better understand the extent of protection and better inform future policy changes.
Extracellular vesicles as circulating cancer biomarkers: opportunities and challenges
Authors: Lane R. E. , Korbie D. , Hill M. M. , Trau M.
Published: May 2018

Extracellular vesicles (EVs) are small, lipid‐bound particles containing nucleic acid and protein cargo which are excreted from cells under a variety of normal and pathological conditions. EVs have garnered substantial research interest in recent years, due to their potential utility as circulating biomarkers for a variety of diseases, including numerous types of cancer. The following review will discuss the current understanding of the form and function of EVs, their specific role in cancer pathogenesis and their potential for non‐invasive disease diagnosis and/or monitoring. This review will also highlight several key issues for this field, including the importance of implementing robust and reproducible sample handling protocols, and the challenge of extracting an EV‐specific biomarker signal from a complex biological background.
The mimetic multiscale method for Maxwell’s equations
Authors: Wilhelms Wenke , Schwarzbach Christoph , Caudillo-Mata Luz Angélica , Haber Eldad
Published: May 2018

We have developed a mimetic multiscale method to simulate quasistatic Maxwell’s equations in the frequency domain. This is especially useful for extensive geophysical models that include small-scale features. Applying the concept of multiscale methods, we avoid setting up a large and costly system of equations on the fine mesh where the material parameters are discretized on. Instead, we build and solve a system on a much coarser mesh. For doing that, it is inevitable to interpolate between fine and coarse meshes. The construction of this coarse-to-fine interpolation is done by solving local, frequency-independent optimization problems for the electric field and the magnetic flux on each coarse cell incorporating the fine-mesh features. Hence, the interpolation operators transfer the fine-mesh material properties onto the coarse simulation mesh. To increase the accuracy of the interpolation, we apply oversampling; i.e., the coarse-cell optimization problems are solved on extended local domains. Previous work on multiscale methods for Maxwell’s equations is not capable of keeping the mimetic properties of the discretization. With our method being mimetic, the properties of the continuous differential operators are preserved in their discrete counterparts and thus, the resulting simulations do not contain spurious modes. We determine the effectiveness of our multiscale construction with coarse-mesh simulations for two examples: a vertical borehole and a mine model.
Thermal conductivity of sandstones from Biot’s coefficient
Authors: Orlander Tobias , Adamopoulou Eirini , Jerver Asmussen Janus , Marczyński Adam Andrzej , Milsch Harald , Pasquinelli Lisa , Lykke Fabricius Ida
Published: May 2018

Thermal conductivity of rocks is typically measured on core samples and cannot be directly measured from logs. We have developed a method to estimate thermal conductivity from logging data, where the key parameter is rock elasticity. This will be relevant for the subsurface industry. Present models for thermal conductivity are typically based primarily on porosity and are limited by inherent constraints and inadequate characterization of the rock texture and can therefore be inaccurate. Provided known or estimated mineralogy, we have developed a theoretical model for prediction of thermal conductivity with application to sandstones. Input parameters are derived from standard logging campaigns through conventional log interpretation. The model is formulated from a simplified rock cube enclosed in a unit volume, where a 1D heat flow passes through constituents in three parallel heat paths: solid, fluid, and solid-fluid in series. The cross section of each path perpendicular to the heat flow represents the rock texture: (1) The cross section with heat transfer through the solid alone is limited by grain contacts, and it is equal to the area governing the material stiffness and quantified through Biot’s coefficient. (2) The cross section with heat transfer through the fluid alone is equal to the area governing fluid flow in the same direction and quantified by a factor analogous to Kozeny’s factor for permeability. (3) The residual cross section involves the residual constituents in the solid-fluid heat path. By using laboratory data for outcrop sandstones and well-log data from a Triassic sandstone formation in Denmark, we compared measured thermal conductivity with our model predictions as well as to the more conventional porosity-based geometric mean. For outcrop material, we find good agreement with model predictions from our work and with the geometric mean, whereas when using well-log data, our model predictions indicate better agreement.
Site characterization with 3D elastic full-waveform tomography
Authors: Nguyen Trung Dung , Tran Khiem T.
Published: May 2018

We have developed a 3D elastic full-waveform inversion (FWI) method for geotechnical site characterization. The method is based on a solution of 3D elastic-wave equations for forward modeling to simulate wave propagation and a local optimization approach based on the adjoint-state method to update the model parameters. The staggered-grid finite-difference technique is used to solve the wave equations together with implementation of the perfectly matched layer condition for boundary truncation. Seismic wavefields are acquired from geophysical testing using sensors and sources located in uniform 2D grids on the ground surface, and they are then inverted for the extraction of 3D subsurface wave velocity structures. The capability of the presented FWI method is tested on synthetic and field data sets. The inversion results from synthetic data indicate the ability of characterizing laterally variable low- and high-velocity layers. Field experimental data were collected using 96 receivers and a propelled energy generator to induce seismic wave energy. The field data result indicates that the waveform analysis was able to delineate variable subsurface soil layers. The seismic inversion results are generally consistent with invasive standard penetration test [Formula: see text]-values, including identification of a low-velocity zone.
Three-term amplitude-variation-with-offset projections
Authors: Ball Vaughn , Tenorio Luis , Schiøtt Christian , Thomas Michelle , Blangy J. P.
Published: May 2018

A three-term (3T) amplitude-variation-with-offset projection is a weighted sum of three elastic reflectivities. Parameterization of the weighting coefficients requires two angle parameters, which we denote by the pair [Formula: see text]. Visualization of this pair is accomplished using a globe-like cartographic representation, in which longitude is [Formula: see text], and latitude is [Formula: see text]. Although the formal extension of existing two-term (2T) projection methods to 3T methods is trivial, practical implementation requires a more comprehensive inversion framework than is required in 2T projections. We distinguish between projections of true elastic reflectivities computed from well logs and reflectivities estimated from seismic data. When elastic reflectivities are computed from well logs, their projection relationships are straightforward, and they are given in a form that depends only on elastic properties. In contrast, projection relationships between reflectivities estimated from seismic may also depend on the maximum angle of incidence and the specific reflectivity inversion method used. Such complications related to projections of seismic-estimated elastic reflectivities are systematized in a 3T projection framework by choosing an unbiased reflectivity triplet as the projection basis. Other biased inversion estimates are then given exactly as 3T projections of the unbiased basis. The 3T projections of elastic reflectivities are connected to Bayesian inversion of other subsurface properties through the statistical notion of Bayesian sufficiency. The triplet of basis reflectivities is computed so that it is Bayes sufficient for all rock properties in the hierarchical seismic rock-physics model; that is, the projection basis contains all information about rock properties that is contained in the original seismic.
Capturing uncertainties through scenario-based integrated static reservoir modeling of lacustrine turbidites in the Barmer Basin, India
Authors: Konar Shubhodip , Majumdar Pinaki , Kumar Prem , Saha Chandan , Krishna Bora Ajoy , Kothari Vachaspati , Shankar Pranay
Published: May 2018

Most static modeling workflows deal with stochastic simulations of the uncertain subsurface parameters on a base case model, although recent studies highlighted usefulness of discrete deterministic multiple geological scenario-based modeling. This paper illustrates the benefits of capturing the principal geological uncertainties through discrete subsurface scenarios, through a case study from the Vijaya and Vandana (V&V) field, Barmer Basin, northwest India. The 12 exploration and appraisal wells have established seven stratigraphically trapped oil pools with the maximum resources confined in the V&V mounds, consisting of turbidite sandstones and conglomerates in a shale background, inferred to be deposited in a deep lacustrine environment. Hydraulic fracturing of these sandstones resulted in significant production increase. Detailed subsurface analysis suggests that the V&V mounds consist of two channel complexes represented by a laterally migrating network of turbidite channels with a maximum thickness of 4–5 m for individual sandstones. Multiattribute seismic studies indicate that delineation of these channel sands, controlled mainly by the channel geometries, cannot be resolved by seismic signature/attribute studies alone, which necessitates the iteration of the facies model into five different scenarios. Each of the facies scenarios is further iterated with other key uncertain input parameters for STOIIP calculation (namely saturation, porosity, contact, etc.) to result in 50 deterministic static realizations that capture the wide uncertainty range of in-place volumes, through a cumulative distribution function plot. In the absence of a defined concept, our model highlights the importance of deterministic depiction of subsurface concepts (geologic, geophysical, petrophysical, and dynamic) through a scenario-based approach. This workflow captures a wide range of various high-impact uncertainties in an integrated manner and links discrete, deterministic, scenario-based outcomes to probabilistic reporting. This will help in the decision-making process by linking the model outcome with long-term well testing and ultimately the concept underlying the development plan.
Seismic Demands in Column Base Connections of Steel Moment Frames
Authors: Torres-Rodas Pablo , Zareian Farzin , Kanvinde Amit
Published: May 2018

Methods for the seismic design of base connections in steel moment frames are well-developed and routinely utilized by practicing engineers. However, design loads for these connections are not verified by rigorous analysis. This knowledge gap is addressed through nonlinear time history simulations using design-level seismic excitation that interrogate demands in column base connections in 2-, 4-, 8-, and 12-story steel moment frames, featuring base connections that reflect current U.S. practice. The results indicate that: (1) for exposed base plate connections, lower bound (rather than peak) estimates of axial compression are suitable for design because higher axial forces increase connection strength by delaying base plate uplift; (2) even when designed as pinned (as in low-rise frames), base connections carry significant moment, which can be estimated only through accurate representation of base flexibility; and (3) the failure of embedded base connections is controlled by moment, which may be estimated either through overstrength or capacity-based calculations.
2016–2017 Central Italy Earthquake Sequence: Seismic Retrofit Policy and Effectiveness
Authors: Mazzoni Silvia , Castori Giulio , Galasso Carmine , Calvi Paolo , Dreyer Richard , Fischer Erica , Fulco Alessandro , Sorrentino Luigi , Wilson Jay , Penna Andrea , Magenes Guido
Published: May 2018

The 2016–2017 Central Italy earthquake sequence consisted of several moderately high-magnitude earthquakes, between M5.5 and M6.5, each centered in a different location and with its own sequences of aftershocks spanning several months. To study the effects of this earthquake sequence on the built environment and the impact on the communities, a collaborative reconnaissance effort was organized by the Earthquake Engineering Research Institute (EERI), the Eucentre Foundation, the European Centre for Training and Research in Earthquake Engineering (EUCentre), and the Rete dei Laboratori Universitari di Ingegneria Sismica (ReLuis). The effort consisted of two reconnaissance missions: one following the Amatrice Earthquake of 24 August 2016 and one after the end of the earthquake sequence, in May 2017. One objective of the reconnaissance effort was to evaluate existing strengthening methodologies and assess their effectiveness in mitigating the damaging effects of ground shaking. Parallel studies by the Geotechnical Extreme Events Reconnaissance (GEER) Association, presented in a companion paper, demonstrate that variations in-ground motions due to topographic site effects had a significant impact on damage distribution in the affected area. This paper presents that, in addition to these ground motion variations, variations in the vulnerability of residential and critical facilities were observed to have a significant impact on the level of damage in the region. The damage to the historical centers of Amatrice and Norcia will be used in this evaluation: the historical center of Amatrice was devastated by the sequence of earthquakes; the significant damage in Norcia was localized to individual buildings. Amatrice has not experienced the same number of devastating earthquakes as Norcia in the last 150 years. As a result, its building stock is much older than that of Norcia and there appeared to be little visual evidence of strengthening of the buildings. The distribution of damage observed throughout the region was found to be indicative of the effectiveness of strengthening and of the need for a comprehensive implementation of retrofit policies.
Development of Deep Shear Wave Velocity Profiles in the Canterbury Plains, New Zealand
Authors: Deschenes Michael R. , Wood Clinton M. , Wotherspoon Liam M. , Bradley Brendon A. , Thomson Ethan
Published: May 2018

Deep (typically > 1,000 m) shear wave velocity ( V S) profiles were developed across the Canterbury region of New Zealand at nine strong-motion stations using a combination of active and passive surface wave methods. A multimode, multimethod joint inversion process, which included Rayleigh and Love wave dispersion and horizontal-to-vertical spectral ratio data, was used to develop the V S profiles at each site. A priori geologic information was used in defining preliminary constraints on the complex geologic layering of the deep basin underlying the region, including velocity reversals in locations where interbedded terrestrial gravels and marine sediments are present. Shear wave profiles developed as part of this study had characteristics comparable to the profiles from 14 Christchurch sites detailed in a separate study. The profiles developed in the two studies were combined to form region-specific V S profiles for typical deposits, which can be used to improve the accuracy of current three-dimensional (3-D) crustal velocity models of the region.
Metabolic Effects of Betaine: A Randomized Clinical Trial of Betaine Supplementation in Prediabetes
Authors: Grizales Ana Maria , Patti Mary-Elizabeth , Lin Alexander P , Beckman Joshua A , Sahni V Anik , Cloutier Emilie , Fowler Kristen M , Dreyfuss Jonathan M , Pan Hui , Kozuka Chisayo , Lee Adrienne , Basu Rita , Pober David M , Gerszten Robert E , Goldfine Allison B
Published: May 2018

Context

Plasma betaine correlates with insulin sensitivity in humans. Betaine supplementation improves metabolic effects in mice fed a high-fat diet.

Objective

To assess metabolic effects of oral betaine in obese participants with prediabetes.

Design

A 12-week, parallel arm, randomized, double-masked, placebo-controlled trial.

Setting

University-affiliated hospital.

Participants and Interventions

Persons with obesity and prediabetes (N = 27) were randomly assigned to receive betaine 3300 mg orally twice daily for 10 days, then 4950 mg twice daily for 12 weeks, or placebo.

Main Outcome Measures

Changes from baseline in insulin sensitivity, glycemia, hepatic fat, and endothelial function.

Results

There was a 16.5-fold increase in plasma dimethylglycine [dimethylglycine (DMG); P < 0.0001] levels, but modest 1.3- and 1.5-fold increases in downstream serine and methionine levels, respectively, in the betaine vs placebo arm. Betaine tended to reduce fasting glucose levels (P = 0.08 vs placebo) but had no other effect on glycemia. Insulin area under curve after oral glucose was reduced for betaine treatment compared with placebo (P = 0.038). Insulin sensitivity, assessed by euglycemic hyperinsulinemic clamp, was not improved. Serum total cholesterol levels increased after betaine treatment compared with placebo (P = 0.032). There were no differences in change in intrahepatic triglyceride or endothelial function between groups.

Conclusion

DMG accumulation supports DMG dehydrogenase as rate limiting for betaine metabolism in persons with prediabetes. Betaine had little metabolic effect. Additional studies may elucidate mechanisms contributing to differences between preclinical and human responses to betaine, and whether supplementation of metabolites downstream of DMG improves metabolism.
Biblical Porn
Authors: Johnson Jessica
Published: May 2018

Between 1996 and 2014, Mark Driscoll's Mars Hill Church multiplied from its base in Seattle into fifteen facilities spread across five states with 13,000 attendees. When it closed, the church was beset by scandal, with former attendees testifying to spiritual abuse, emotional manipulation, and financial exploitation. In Biblical Porn Jessica Johnson examines how Mars Hill's congregants became entangled in processes of religious conviction. Johnson shows how they were affectively recruited into sexualized and militarized dynamics of power through the mobilization of what she calls "biblical porn"—the affective labor of communicating, promoting, and embodying Driscoll's teaching on biblical masculinity, femininity, and sexuality, which simultaneously worked as a marketing strategy, social imaginary, and biopolitical instrument. Johnson theorizes religious conviction as a social process through which Mars Hill's congregants circulated and amplified feelings of hope, joy, shame, and paranoia as affective value that the church capitalized on to grow at all costs.