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The efficacy of future human-machine teaming will be determined by the ability of machine agents to engage in teamwork behaviors and processes with their human teammates. A critical aspect of teamwork is cooperation, as team members must work interdependently to achieve common goals. In the current experiment we investigated how violations of cooperation expectations, presented to participants in a narrative vignette, influenced ratings of cooperation on a novel measure derived from social interdependence theory. Our results indicated that participants’ ratings of cooperation were strongly influenced by actions associated with assisting and communicating with a cooperating partner; violations in these expectations resulted in much lower estimates of cooperation, though the identity of the actors as two humans or a human and a robot did not appear to matter. Overall, this is an important first step to understanding the factors that influence perceptions of cooperation in human-machine teaming.

A microfluidic paper-based analytical device (μPAD) is a cost-effective platform to implement assays, especially for point-of-care testing. Developing μPADs with fluidic control is important to implement multistep assays and provide high sensitivities. However, current localized delays in μPADs made of sucrose have a limited ability to decrease the flow rate. In addition, existing μPADs for automatic multistep assays are limited by their need for auxiliary instruments, their false activation, or their unavoidable tradeoff between available fluid volumes and temporal differences between steps. Here, a novel μPAD composed of a localized dissolvable delay and a horizontal motion mechanical valve for use as an automatic multistep assay is reported. A mixture of fructose and sucrose was used in the localized dissolvable delay and it provided an effective decrease in the flow rate to ensure adequate sensitivity in an assay. The dissolvable delay effectively doubled the flow time. A mechanical valve using a horizontal movement was developed to automatically implement a multistep process. Two-step and four-step processes were enabled with the μPAD. Cardiac troponin I (cTnI), a gold-standard biomarker for myocardial infarction, was used as a model analyte to show the performance of the developed μPAD in an assay. The designed μPAD, with the simple-to-make localized dissolvable delay and the robust mechanical valve, provides the potential to automatically implement high-performance multistep assays toward a versatile platform for point-of-care diagnostics.

Significance: Cardiac troponin I (cTnI) is a primary biomarker for diagnosis of myocardial infarction (MI). In contrast to central laboratory tests for cTnI, point-of-care (POC) testing has the advantage of providing results when the patient is first encountered, which helps high-risk patients to be treated more rapidly and low-risk patients to be released in a timely fashion. A paper fluidic platform is good for POC testing because the paper is abundant, low cost, and disposable. However, current cTnI assays on paper platforms use antibodies as the recognition element, which has limitations due to the high cost of production and antibody stability issues at the POC. Aim: To develop an aptamer-based assay on a paper strip using surface-enhanced resonance Raman spectroscopy (SERRS) for detection of cTnI in the clinically relevant range at the POC. Approach: Gold nanoparticles (AuNPs) were functionalized with a Raman reporter molecule, malachite green isothiocyanate. The functionalized AuNPs were encapsulated in a silica shell and provided a SERRS signal using a handheld Raman system with a 638-nm excitation wavelength. A primary aptamer and a secondary aptamer of cTnI were used in a sandwich assay format to bind the cTnI on a test line of a paper fluidic platform. By measuring the SERRS signal from the test line, the concentration of cTnI was quantitatively determined. Results: The aptamer-based SERRS assay on a paper strip had a detection range of 0.016 to 0.1 ng/ml for cTnI, had good selectivity for cTnI compared to three other markers, had good stability over 10 days, and had good performance in the more complex serum sample matrix. Conclusions: The aptamer-based SERRS assay on a paper strip has the potential to provide a sensitive, selective, stable, repeatable, and cost-effective platform for the detection of cTnI toward eventual use in diagnosis of MI at the POC.

The accurate and rapid diagnosis of myocardial infarction (MI) is essential to implement timely and definitive treatment to the patient. Cardiac Troponin I (cTnI) has been widely used as a biomarker for early diagnosis of MI. Point-of-care (POC) testing is favored because it can provide timely results when the patient is first encountered (e.g. ambulance, clinic, or emergency department). However, the clinical cut-off of cTnI for diagnosis of MI is in the pico- to femtomolar range (i.e. 0.01-0.1 ng/ml). Thus, a sensitive sensing system is needed to quantitively measure cTnI at the POC. Surface-enhanced Raman spectroscopy (SERS) is a sensitive optical technique that can be used to measure trace analytes in a sample. Moreover, paper-based sensing systems have demonstrated potential as a platform to implement assays, especially at the POC. This research describes the development of a paper-based SERS assay for detection of cTnI in the physiological relevant range. Aptamer is used in the assay for recognizing the cTnI in a sample. SERS is used to sensitively transduce the sensing signal from the assay. A handheld Raman spectrometer is used to measure the SERS signal. By measuring the change in the SERS signal, the concentration of target molecule is quantitatively determined. Moreover, spectral processing techniques are used to evaluate their effect on signal-to-noise ratio as well as sensitivity of the assay. Results showed the designed sensing system can be used to measure cTnI (0-0.5 ng/mL) in standard buffer solutions.

In North America, the transition from more conventional reservoirs into tight, basin-centered gas and now source shales has caused the industry to change the way reservoir performance is being assessed, measured, and documented. Historically in conventional reservoirs the reservoir quality was carefully examined on a well by well basis to determine reserves in place and exploitation plans. For unconventional reservoirs, however, the commercializing of such plays quickly became centered on horizontal drilling of long laterals combined with massive volume, high rate multi-stage hydraulic fracturing. In that environment, completion design and hydraulic fracturing have become more of a statistical process; additionally, incremental improvement and innovation are used to create a treatment schedule often replicated across an entire field without consideration of reservoir variability across a lateral. Based upon vertical well experience, the fracture initiation points can be carefully selected by identifying the locations within the well that are best to perforate. In a horizontal well, however, the location of the lateral defines the fracture initiation points anywhere along the well, so the stratigraphic location of the well lateral becomes critical in non-homogeneous shale plays. To address this, engineers and geoscientists can identify important parameters necessary for optimum completion design, and earth modelling can then be used as a tool to capture and model these properties across the asset making critical information available as needed for drilling, completion, and production operations.

Summary Throughout the past several years, economic and technological advancements in the North American shale market with respect to drilling and hydraulic-fracturing operations have helped create a “typical” operating scheme for producing from the multiple shale-formation reservoirs currently being exploited. This typical scheme focuses on operational efficiency and cost reduction to drive profitability in these markets. Although operational efficiency and effective cost control have led to more-profitable operations in these shale reservoirs, the unknowns regarding the subsurface of these highly complex formations can often create situations of operating without sufficient information to optimally design drilling-and-completions strategies to produce larger volumes of hydrocarbon from the reservoir. Opposed to conventional operations, the amount of basin and asset knowledge being collected and developed in most of these shale plays is much lower, and thus can result in poor development decisions, leading to less than optimum economic performance. Focus on subsurface knowledge as well as collaboration between the various aspects of developing an asset is essential to helping discover and produce more oil and gas from these complex reservoir systems. This paper examines a case study of three wells in Wise County, Texas, in the Barnett shale, where a collaborative subsurface insight investigation and a drilling-and-completions optimization process were used to illustrate the production benefit achieved through improved reservoir understanding. Within this process, an asset Earth model was created with the collected information from wireline logging, logging while drilling, core testing, mechanical rock and fluid properties, formation mineralogy, and wellbore-image logging. In addition, for the completions-design strategy, microseismic measurement and image-log fracture matching and complex-fracture modeling software tools were used to define and model the growth of the stimulated fracture network during hydraulic-fracturing completions. This paper presents an overview of “typical” previous completions and subsurface information collected before implementation of the new process in comparison to changes made to the drilling-and-completions designs used on three wells, as well as an overview of the types of information collected to supply the Earth model. Examples of the fracture matching and complex-fracture modeling for the wells help illustrate the design and optimization of hydraulic-fracturing treatments in a complex shale reservoir. Finally, a production-results comparison is presented to illustrate a significant increase to production of hydrocarbon through better reservoir understanding and drilling-and-completion designs.

Although the prey of Reddish Egrets (Egretta rufescens) generally consists of shallow-water, euryhaline fish species, rangewide differences in breeding season diet have not been examined. Furthermore, the relative proportions of the two Reddish Egret color morphs vary from east to west across the species' range. Color morph may influence foraging efficiency, but variations in prey across the species' range and between morphs is undocumented. By examining boluses from Reddish Egret (n = 109) nestlings, prey species proportions were compared between morphs, among regions and among colonies within Texas. Between regions, prey species and proportion of species differed widely; however, fish species with similar life histories were selected across the Reddish Egret's range (Bahamas: 100% sheepshead minnow (Cyprinodon variegatus); Texas: 85% sheepshead minnow; Baja California Sur: 49% American shadow goby (Quietula y-cauda); Yucatan: 64% Yucatan pupfish (C. artifrons)). Within the Laguna Madre in Texa...

This paper discusses a study of condensate-rich Barnett Shale stimulation treatments with designs incorporating a micro-proppant (MP). By placing this proppant early during treatment, it can enter into the narrow natural fracture network where proppant even as small as 100 mesh cannot access. A description of the MP, area regional formation and fracture modeling, stimulation designs, reservoir simulation production results, and production comparisons to offsets are presented. In present day shale plays, maximizing communication between natural fracture systems and the wellbore while also avoiding any damage to those natural fractures are two pillars of optimized stimulation. Increased proppant volume in primary fractures and helping ensure the near-wellbore (NWB) area of these fractures is open are two important stimulation concepts. Further improvements depend on: Communicating with a greater number of natural fractures. Enhancing the number of secondary fractures opened. Increasing the number of these secondary fractures that remain open for the long term. Of these three items listed, the third is probably the most challenging. This paper presents a study of MP use with the goal of propping natural fractures in a liquids-rich area of the Barnett, wherein the first and second items listed have already been addressed and provided significant production improvement. A well-to-well comparison of MP use revealed another step-change in an otherwise optimized drilling and completion program. Production history matching using advanced discrete fracture network (DFN) simulations of hydraulic fractures with the complexity of natural fractures included helped provide insight into how relatively small conductivity improvement to the natural fractures significantly improved well productivity. A new complex fracture design simulator successfully predicted the most favorable method within the fracturing design to include a MP entering these narrow natural fractures and thus improving conductivity. With the understanding gained from these new modeling tools, the MP was then field tested and proven to enhance production response.

Within the ever increasing collaborative environment of the oil and gas industry, there has been significant growth in the need for professionals to be able to operate across industry-standard definitions of disciplines. Influences, such as economic cycles, growth in other industries, and population growth have created a growing demand for young professionals to assume responsibilities and management duties at a rapid pace. While educational advances within the university setting are making efforts to close the gap necessary to supplement this demand, the majority of the responsibility to develop competent employees lies with the employer. Employers within the industry are beginning to realize and act on the need for structured training and development programs to help ensure employees are adequately prepared and familiar with multiple concepts of business, even across historically set up discipline divisions. This is particularly true within technical disciplines, because there is a great demand for these technical employees to fulfill roles and responsibilities that push them beyond their technical training and typical roles. Moreover, the rapid increase in the use of technology necessary to operate in the unconventional reservoir setting has created a situation of dependency on these technical employees to take on managerial and strategic business-focused roles. Historically, technical employees within the oil and gas industry have operated within specific niches according to their education and/or experience. However, an increase in multidisciplinary project management as it relates to asset development suggests the need for technical employees to develop themselves across discipline boundaries. Training and development programs that cover all aspects, from geology and geophysics, drilling, completions, production, and asset management, are essential to prepare these young professionals for the responsibilities within this setting. In addition to broader technical training, soft skills training to adequately prepare technical employees to express difficult concepts coherently and effectively is paramount to bridging the gap between the technical and nontechnical portions of the industry. This paper outlines suggested advances that can be made to effectively train and develop technical employees in this evolving setting during entry level training and more specifically mid-career professional development. A description of historical training methods in the industry, current trends of training technical employees within a certain discipline, and the developing understanding of the importance of multidisciplinary technical collaboration are also discussed.

Throughout the past several years, economic and technological advancements in the North American shale market with respect to drilling and hydraulic fracturing operations have helped create a "typical" operating scheme for producing from the multiple shale formation reservoirs currently being exploited. This typical scheme focuses on operational efficiency and cost reduction to drive profitability in these markets. While operational efficiency and effective cost control have led to more profitable operations in these shale reservoirs, the unknowns regarding the subsurface of these highly complex formations can often create situations of operating without sufficient information to optimally design drilling and completions strategies to produce larger volumes of hydrocarbon from the reservoir. Opposed to conventional operations, the amount of basin and asset knowledge being collected and developed in most of these shale plays is much lower, and thus can result in poor development decisions, leading to less than optimum economic performance. Focus on subsurface knowledge as well as collaboration between the various aspects of developing an asset is essential to helping discover and produce more oil and gas from these complex reservoir systems. This paper examines a case study of three wells in Wise County, Texas, in the Barnett shale, where a collaborative subsurface insight investigation and drilling and completions optimization process were used to illustrate the production benefit achieved through improved reservoir understanding. Within this process, an asset earth model was created using the collected information from wireline logging, logging while drilling (LWD), core testing, mechanical rock and fluid properties, formation mineralogy, and wellbore image logging. Additionally, for the completions design strategy, microseismic measurement and image log fracture matching and complex fracture modeling software tools were used to define and model the growth of the stimulated fracture network during hydraulic fracturing completions. This paper presents an overview of "typical" previous completions and subsurface information collected before implementation of the new process in comparison to changes made to the drilling and completions designs used on three wells, as well as an overview of the types of information collected to supply the earth model. Examples of the fracture matching and complex fracture modeling for the wells helps illustrate the design and optimization of hydraulic fracturing treatments in a complex shale reservoir. Finally, a production results comparison is presented to illustrate a significant increase to production of hydrocarbon through better reservoir understanding and drilling and completion designs.

Bandura's (1982) self-efficacy theory was applied to explain the process by which self-efficacy for managing pediatric diseases can be enhanced. Adolescents (N = 143) diagnosed with insulin-dependent diabetes mellitus (IDDM) completed measures of adherence to IDDM treatment, self-efficacy for diabetes care, personal responsibility for diabetes care, and a measure of supportive and nonsupportive diabetes-specific behaviors exhibited by their parents. Self-efficacy was tested as a mediator variable for hypothesized relations between adherence to treatment and 2 methods proposed to enhance self-efficacy, including mastery experience (i.e., responsibility for treatment) and social persuasion (i.e., supportive and nonsupportive parental behaviors). Regression analyses revealed support for self-efficacy as a mediator variable for the relation between mastery experience and adherence to treatment. Self-efficacy was also a mediator variable for the relation between nonsupportive parental behaviors and adolescents...