User Requirements for a Chronic Kidney Disease Clinical Decision Support Tool to Promote Timely Referral.

PubMed

Gulla, Joy; Neri, Pamela M; Bates, David W; Samal, Lipika

2017-05-01

Timely referral of patients with CKD has been associated with cost and mortality benefits, but referrals are often done too late in the course of the disease. Clinical decision support (CDS) offers a potential solution, but interventions have failed because they were not designed to support the physician workflow. We sought to identify user requirements for a chronic kidney disease (CKD) CDS system to promote timely referral. We interviewed primary care physicians (PCPs) to identify data needs for a CKD CDS system that would encourage timely referral and also gathered information about workflow to assess risk factors for progression of CKD. Interviewees were general internists recruited from a network of 14 primary care clinics affiliated with Brigham and Women's Hospital (BWH). We then performed a qualitative analysis to identify user requirements and system attributes for a CKD CDS system. Of the 12 participants, 25% were women, the mean age was 53 (range 37-82), mean years in clinical practice was 27 (range 11-58). We identified 21 user requirements. Seven of these user requirements were related to support for the referral process workflow, including access to pertinent information and support for longitudinal co-management. Six user requirements were relevant to PCP management of CKD, including management of risk factors for progression, interpretation of biomarkers of CKD severity, and diagnosis of the cause of CKD. Finally, eight user requirements addressed user-centered design of CDS, including the need for actionable information, links to guidelines and reference materials, and visualization of trends. These 21 user requirements can be used to design an intuitive and usable CDS system with the attributes necessary to promote timely referral. Copyright © 2017 Elsevier B.V. All rights reserved.

Towards meaningful medication-related clinical decision support: recommendations for an initial implementation.

PubMed

Phansalkar, S; Wright, A; Kuperman, G J; Vaida, A J; Bobb, A M; Jenders, R A; Payne, T H; Halamka, J; Bloomrosen, M; Bates, D W

2011-01-01

Clinical decision support (CDS) can improve safety, quality, and cost-effectiveness of patient care, especially when implemented in computerized provider order entry (CPOE) applications. Medication-related decision support logic forms a large component of the CDS logic in any CPOE system. However, organizations wishing to implement CDS must either purchase the computable clinical content or develop it themselves. Content provided by vendors does not always meet local expectations. Most organizations lack the resources to customize the clinical content and the expertise to implement it effectively. In this paper, we describe the recommendations of a national expert panel on two basic medication-related CDS areas, specifically, drug-drug interaction (DDI) checking and duplicate therapy checking. The goals of this study were to define a starter set of medication-related alerts that healthcare organizations can implement in their clinical information systems. We also draw on the experiences of diverse institutions to highlight the realities of implementing medication decision support. These findings represent the experiences of institutions with a long history in the domain of medication decision support, and the hope is that this guidance may improve the feasibility and efficiency CDS adoption across healthcare settings.

Clinical Decision Support in Electronic Prescribing: Recommendations and an Action Plan

PubMed Central

Teich, Jonathan M.; Osheroff, Jerome A.; Pifer, Eric A.; Sittig, Dean F.; Jenders, Robert A.

2005-01-01

Clinical decision support (CDS) in electronic prescribing (eRx) systems can improve the safety, quality, efficiency, and cost-effectiveness of care. However, at present, these potential benefits have not been fully realized. In this consensus white paper, we set forth recommendations and action plans in three critical domains: (1) advances in system capabilities, including basic and advanced sets of CDS interventions and knowledge, supporting database elements, operational features to improve usability and measure performance, and management and governance structures; (2) uniform standards, vocabularies, and centralized knowledge structures and services that could reduce rework by vendors and care providers, improve dissemination of well-constructed CDS interventions, promote generally applicable research in CDS methods, and accelerate the movement of new medical knowledge from research to practice; and (3) appropriate financial and legal incentives to promote adoption. PMID:15802474

A Clinical Decision Support Engine Based on a National Medication Repository for the Detection of Potential Duplicate Medications: Design and Evaluation.

PubMed

Yang, Cheng-Yi; Lo, Yu-Sheng; Chen, Ray-Jade; Liu, Chien-Tsai

2018-01-19

A computerized physician order entry (CPOE) system combined with a clinical decision support system can reduce duplication of medications and thus adverse drug reactions. However, without infrastructure that supports patients' integrated medication history across health care facilities nationwide, duplication of medication can still occur. In Taiwan, the National Health Insurance Administration has implemented a national medication repository and Web-based query system known as the PharmaCloud, which allows physicians to access their patients' medication records prescribed by different health care facilities across Taiwan. This study aimed to develop a scalable, flexible, and thematic design-based clinical decision support (CDS) engine, which integrates a national medication repository to support CPOE systems in the detection of potential duplication of medication across health care facilities, as well as to analyze its impact on clinical encounters. A CDS engine was developed that can download patients' up-to-date medication history from the PharmaCloud and support a CPOE system in the detection of potential duplicate medications. When prescribing a medication order using the CPOE system, a physician receives an alert if there is a potential duplicate medication. To investigate the impact of the CDS engine on clinical encounters in outpatient services, a clinical encounter log was created to collect information about time, prescribed drugs, and physicians' responses to handling the alerts for each encounter. The CDS engine was installed in a teaching affiliate hospital, and the clinical encounter log collected information for 3 months, during which a total of 178,300 prescriptions were prescribed in the outpatient departments. In all, 43,844/178,300 (24.59%) patients signed the PharmaCloud consent form allowing their physicians to access their medication history in the PharmaCloud. The rate of duplicate medication was 5.83% (1843/31,614) of prescriptions. When prescribing using the CDS engine, the median encounter time was 4.3 (IQR 2.3-7.3) min, longer than that without using the CDS engine (median 3.6, IQR 2.0-6.3 min). From the physicians' responses, we found that 42.06% (1908/4536) of the potential duplicate medications were recognized by the physicians and the medication orders were canceled. The CDS engine could easily extend functions for detection of adverse drug reactions when more and more electronic health record systems are adopted. Moreover, the CDS engine can retrieve more updated and completed medication histories in the PharmaCloud, so it can have better performance for detection of duplicate medications. Although our CDS engine approach could enhance medication safety, it would make for a longer encounter time. This problem can be mitigated by careful evaluation of adopted solutions for implementation of the CDS engine. The successful key component of a CDS engine is the completeness of the patient's medication history, thus further research to assess the factors in increasing the PharmaCloud consent rate is required. ©Cheng-Yi Yang, Yu-Sheng Lo, Ray-Jade Chen, Chien-Tsai Liu. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 19.01.2018.

Automating Performance Measures and Clinical Practice Guidelines: Differences and Complementarities.

PubMed

Tu, Samson W; Martins, Susana; Oshiro, Connie; Yuen, Kaeli; Wang, Dan; Robinson, Amy; Ashcraft, Michael; Heidenreich, Paul A; Goldstein, Mary K

2016-01-01

Through close analysis of two pairs of systems that implement the automated evaluation of performance measures (PMs) and guideline-based clinical decision support (CDS), we contrast differences in their knowledge encoding and necessary changes to a CDS system that provides management recommendations for patients failing performance measures. We trace the sources of differences to the implementation environments and goals of PMs and CDS.

Reducing risk with clinical decision support: a study of closed malpractice claims.

PubMed

Zuccotti, G; Maloney, F L; Feblowitz, J; Samal, L; Sato, L; Wright, A

2014-01-01

Identify clinical opportunities to intervene to prevent a malpractice event and determine the proportion of malpractice claims potentially preventable by clinical decision support (CDS). Cross-sectional review of closed malpractice claims over seven years from one malpractice insurance company and seven hospitals in the Boston area. For each event, clinical opportunities to intervene to avert the malpractice event and the presence or absence of CDS that might have a role in preventing the event, were assigned by a panel of expert raters. Compensation paid out to resolve a claim (indemnity), was associated with each CDS type. Of the 477 closed malpractice cases, 359 (75.3%) were categorized as substantiated and 195 (54%) had at least one opportunity to intervene. Common opportunities to intervene related to performance of procedure, diagnosis, and fall prevention. We identified at least one CDS type for 63% of substantiated claims. The 41 CDS types identified included clinically significant test result alerting, diagnostic decision support and electronic tracking of instruments. Cases with at least one associated intervention accounted for $40.3 million (58.9%) of indemnity. CDS systems and other forms of health information technology (HIT) are expected to improve quality of care, but their potential to mitigate risk had not previously been quantified. Our results suggest that, in addition to their known benefits for quality and safety, CDS systems within HIT have a potential role in decreasing malpractice payments. More than half of malpractice events and over $40 million of indemnity were potentially preventable with CDS.

Honeywell Cascade Distiller System Performance Testing Interim Results

NASA Technical Reports Server (NTRS)

Callahan, Michael R.; Sargusingh, Miriam

2014-01-01

The ability to recover and purify water through physiochemical processes is crucial for realizing long-term human space missions, including both planetary habitation and space travel. Because of their robust nature, distillation systems have been actively pursued as one of the technologies for water recovery. The Cascade Distillation System (CDS) is a vacuum rotary distillation system with potential for greater reliability and lower energy costs than existing distillation systems. The CDS was previously under development through Honeywell and NASA. In 2009, an assessment was performed to collect data to support down-selection and development of a primary distillation technology for application in a lunar outpost water recovery system. Based on the results of this testing, an expert panel concluded that the CDS showed adequate development maturity, TRL-4, together with the best product water quality and competitive weight and power estimates to warrant further development. The Advanced Exploration Systems (AES) Water Recovery Project (WRP) worked to address weaknesses identified by The Panel; namely bearing design and heat pump power efficiency. Testing at the NASA-JSC Advanced Exploration System Water Laboratory (AES Water Lab) using a prototype Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell International, Torrance, Calif.) with test support equipment and control system developed by Johnson Space Center was performed to evaluate performance of the system with the upgrades. The CDS will also have been challenged with ISS analog waste streams and a subset of those being considered for Exploration architectures. This paper details interim results of the AES WRP CDS performance testing.

Analysis of Nursing Clinical Decision Support Requests and Strategic Plan in a Large Academic Health System

PubMed Central

Bavuso, Karen; Bouyer-Ferullo, Sharon; Goldsmith, Denise; Fairbanks, Amanda; Gesner, Emily; Lagor, Charles; Collins, Sarah

2016-01-01

Summary Objectives To understand requests for nursing Clinical Decision Support (CDS) interventions at a large integrated health system undergoing vendor-based EHR implementation. In addition, to establish a process to guide both short-term implementation and long-term strategic goals to meet nursing CDS needs. Materials and Methods We conducted an environmental scan to understand current state of nursing CDS over three months. The environmental scan consisted of a literature review and an analysis of CDS requests received from across our health system. We identified existing high priority CDS and paper-based tools used in nursing practice at our health system that guide decision-making. Results A total of 46 nursing CDS requests were received. Fifty-six percent (n=26) were specific to a clinical specialty; 22 percent (n=10) were focused on facilitating clinical consults in the inpatient setting. “Risk Assessments/Risk Reduction/Promotion of Healthy Habits” (n=23) was the most requested High Priority Category received for nursing CDS. A continuum of types of nursing CDS needs emerged using the Data-Information-Knowledge-Wisdom Conceptual Framework: 1) facilitating data capture, 2) meeting information needs, 3) guiding knowledge-based decision making, and 4) exposing analytics for wisdom-based clinical interpretation by the nurse. Conclusion Identifying and prioritizing paper-based tools that can be modified into electronic CDS is a challenge. CDS strategy is an evolving process that relies on close collaboration and engagement with clinical sites for short-term implementation and should be incorporated into a long-term strategic plan that can be optimized and achieved overtime. The Data-Information-Knowledge-Wisdom Conceptual Framework in conjunction with the High Priority Categories established may be a useful tool to guide a strategic approach for meeting short-term nursing CDS needs and aligning with the organizational strategic plan. PMID:27437036

Boosting Quality Registries with Clinical Decision Support Functionality*. User Acceptance of a Prototype Applied to HIV/TB Drug Therapy.

PubMed

Wannheden, Carolina; Hvitfeldt-Forsberg, Helena; Eftimovska, Elena; Westling, Katarina; Ellenius, Johan

2017-08-11

The care of HIV-related tuberculosis (HIV/TB) is complex and challenging. Clinical decision support (CDS) systems can contribute to improve quality of care, but more knowledge is needed on factors determining user acceptance of CDS. To analyze physicians' and nurses' acceptance of a CDS prototype for evidence-based drug therapy recommendations for HIV/TB treatment. Physicians and nurses were involved in designing a CDS prototype intended for future integration with the Swedish national HIV quality registry. Focus group evaluation was performed with ten nurses and four physicians, respectively. The Unified Theory of Acceptance and Use of Technology (UTAUT) was used to analyze acceptance. We identified several potential benefits with the CDS prototype as well as some concerns that could be addressed by redesign. There was also concern about dependence on physician attitudes, as well as technical, organizational, and legal issues. Acceptance evaluation at a prototype stage provided rich data to improve the future design of a CDS prototype. Apart from design and development efforts, substantial organizational efforts are needed to enable the implementation and maintenance of a future CDS system.

Medication-related clinical decision support in computerized provider order entry systems: a review.

PubMed

Kuperman, Gilad J; Bobb, Anne; Payne, Thomas H; Avery, Anthony J; Gandhi, Tejal K; Burns, Gerard; Classen, David C; Bates, David W

2007-01-01

While medications can improve patients' health, the process of prescribing them is complex and error prone, and medication errors cause many preventable injuries. Computer provider order entry (CPOE) with clinical decision support (CDS), can improve patient safety and lower medication-related costs. To realize the medication-related benefits of CDS within CPOE, one must overcome significant challenges. Healthcare organizations implementing CPOE must understand what classes of CDS their CPOE systems can support, assure that clinical knowledge underlying their CDS systems is reasonable, and appropriately represent electronic patient data. These issues often influence to what extent an institution will succeed with its CPOE implementation and achieve its desired goals. Medication-related decision support is probably best introduced into healthcare organizations in two stages, basic and advanced. Basic decision support includes drug-allergy checking, basic dosing guidance, formulary decision support, duplicate therapy checking, and drug-drug interaction checking. Advanced decision support includes dosing support for renal insufficiency and geriatric patients, guidance for medication-related laboratory testing, drug-pregnancy checking, and drug-disease contraindication checking. In this paper, the authors outline some of the challenges associated with both basic and advanced decision support and discuss how those challenges might be addressed. The authors conclude with summary recommendations for delivering effective medication-related clinical decision support addressed to healthcare organizations, application and knowledge base vendors, policy makers, and researchers.

Thinking Together: Modeling Clinical Decision-Support as a Sociotechnical System

PubMed Central

Hussain, Mustafa I.; Reynolds, Tera L.; Mousavi, Fatemeh E.; Chen, Yunan; Zheng, Kai

2017-01-01

Computerized clinical decision-support systems are members of larger sociotechnical systems, composed of human and automated actors, who send, receive, and manipulate artifacts. Sociotechnical consideration is rare in the literature. This makes it difficult to comparatively evaluate the success of CDS implementations, and it may also indicate that sociotechnical context receives inadequate consideration in practice. To facilitate sociotechnical consideration, we developed the Thinking Together model, a flexible diagrammatical means of representing CDS systems as sociotechnical systems. To develop this model, we examined the literature with the lens of Distributed Cognition (DCog) theory. We then present two case studies of vastly different CDSSs, one almost fully automated and the other with minimal automation, to illustrate the flexibility of the Thinking Together model. We show that this model, informed by DCog and the CDS literature, are capable of supporting both research, by enabling comparative evaluation, and practice, by facilitating explicit sociotechnical planning and communication. PMID:29854164

Standard practices for computerized clinical decision support in community hospitals: a national survey

PubMed Central

McCormack, James L; Sittig, Dean F; Wright, Adam; McMullen, Carmit; Bates, David W

2012-01-01

Objective Computerized provider order entry (CPOE) with clinical decision support (CDS) can help hospitals improve care. Little is known about what CDS is presently in use and how it is managed, however, especially in community hospitals. This study sought to address this knowledge gap by identifying standard practices related to CDS in US community hospitals with mature CPOE systems. Materials and Methods Representatives of 34 community hospitals, each of which had over 5 years experience with CPOE, were interviewed to identify standard practices related to CDS. Data were analyzed with a mix of descriptive statistics and qualitative approaches to the identification of patterns, themes and trends. Results This broad sample of community hospitals had robust levels of CDS despite their small size and the independent nature of many of their physician staff members. The hospitals uniformly used medication alerts and order sets, had sophisticated governance procedures for CDS, and employed staff to customize CDS. Discussion The level of customization needed for most CDS before implementation was greater than expected. Customization requires skilled individuals who represent an emerging manpower need at this type of hospital. Conclusion These results bode well for robust diffusion of CDS to similar hospitals in the process of adopting CDS and suggest that national policies to promote CDS use may be successful. PMID:22707744

Reducing Risk with Clinical Decision Support

PubMed Central

Maloney, F.L.; Feblowitz, J.; Samal, L.; Sato, L.; Wright, A.

2014-01-01

Summary Objective Identify clinical opportunities to intervene to prevent a malpractice event and determine the proportion of malpractice claims potentially preventable by clinical decision support (CDS). Materials and Methods Cross-sectional review of closed malpractice claims over seven years from one malpractice insurance company and seven hospitals in the Boston area. For each event, clinical opportunities to intervene to avert the malpractice event and the presence or absence of CDS that might have a role in preventing the event, were assigned by a panel of expert raters. Compensation paid out to resolve a claim (indemnity), was associated with each CDS type. Results Of the 477 closed malpractice cases, 359 (75.3%) were categorized as substantiated and 195 (54%) had at least one opportunity to intervene. Common opportunities to intervene related to performance of procedure, diagnosis, and fall prevention. We identified at least one CDS type for 63% of substantiated claims. The 41 CDS types identified included clinically significant test result alerting, diagnostic decision support and electronic tracking of instruments. Cases with at least one associated intervention accounted for $40.3 million (58.9%) of indemnity. Discussion CDS systems and other forms of health information technology (HIT) are expected to improve quality of care, but their potential to mitigate risk had not previously been quantified. Our results suggest that, in addition to their known benefits for quality and safety, CDS systems within HIT have a potential role in decreasing malpractice payments. Conclusion More than half of malpractice events and over $40 million of indemnity were potentially preventable with CDS. PMID:25298814

Cascade Distiller System Performance Testing Interim Results

NASA Technical Reports Server (NTRS)

Callahan, Michael R.; Pensinger, Stuart; Sargusingh, Miriam J.

2014-01-01

The Cascade Distillation System (CDS) is a rotary distillation system with potential for greater reliability and lower energy costs than existing distillation systems. Based upon the results of the 2009 distillation comparison test (DCT) and recommendations of the expert panel, the Advanced Exploration Systems (AES) Water Recovery Project (WRP) project advanced the technology by increasing reliability of the system through redesign of bearing assemblies and improved rotor dynamics. In addition, the project improved the CDS power efficiency by optimizing the thermoelectric heat pump (TeHP) and heat exchanger design. Testing at the NASA-JSC Advanced Exploration System Water Laboratory (AES Water Lab) using a prototype Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell d International, Torrance, Calif.) with test support equipment and control system developed by Johnson Space Center was performed to evaluate performance of the system with the upgrades as compared to previous system performance. The system was challenged with Solution 1 from the NASA Exploration Life Support (ELS) distillation comparison testing performed in 2009. Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. A secondary objective of this testing is to evaluate the performance of the CDS as compared to the state of the art Distillation Assembly (DA) used in the ISS Urine Processor Assembly (UPA). This was done by challenging the system with ISS analog waste streams. This paper details the results of the AES WRP CDS performance testing.

Clinical guideline representation in a CDS: a human information processing method.

PubMed

Kilsdonk, Ellen; Riezebos, Rinke; Kremer, Leontien; Peute, Linda; Jaspers, Monique

2012-01-01

The Dutch Childhood Oncology Group (DCOG) has developed evidence-based guidelines for screening childhood cancer survivors for possible late complications of treatment. These paper-based guidelines appeared to not suit clinicians' information retrieval strategies; it was thus decided to communicate the guidelines through a Computerized Decision Support (CDS) tool. To ensure high usability of this tool, an analysis of clinicians' cognitive strategies in retrieving information from the paper-based guidelines was used as requirements elicitation method. An information processing model was developed through an analysis of think aloud protocols and used as input for the design of the CDS user interface. Usability analysis of the user interface showed that the navigational structure of the CDS tool fitted well with the clinicians' mental strategies employed in deciding on survivors screening protocols. Clinicians were more efficient and more complete in deciding on patient-tailored screening procedures when supported by the CDS tool than by the paper-based guideline booklet. The think-aloud method provided detailed insight into users' clinical work patterns that supported the design of a highly usable CDS system.

What can Natural Language Processing do for Clinical Decision Support?

PubMed Central

Demner-Fushman, Dina; Chapman, Wendy W.; McDonald, Clement J.

2009-01-01

Computerized Clinical Decision Support (CDS) aims to aid decision making of health care providers and the public by providing easily accessible health-related information at the point and time it is needed. Natural Language Processing (NLP) is instrumental in using free-text information to drive CDS, representing clinical knowledge and CDS interventions in standardized formats, and leveraging clinical narrative. The early innovative NLP research of clinical narrative was followed by a period of stable research conducted at the major clinical centers and a shift of mainstream interest to biomedical NLP. This review primarily focuses on the recently renewed interest in development of fundamental NLP methods and advances in the NLP systems for CDS. The current solutions to challenges posed by distinct sublanguages, intended user groups, and support goals are discussed. PMID:19683066

Cascade Distillation Subsystem Development: Progress Toward a Distillation Comparison Test

NASA Technical Reports Server (NTRS)

Callahan, M. R.; Lubman, A.; Pickering, Karen D.

2009-01-01

Recovery of potable water from wastewater is essential for the success of long-duration manned missions to the Moon and Mars. Honeywell International and a team from NASA Johnson Space Center (JSC) are developing a wastewater processing subsystem that is based on centrifugal vacuum distillation. The wastewater processor, referred to as the Cascade Distillation Subsystem (CDS), utilizes an innovative and efficient multistage thermodynamic process to produce purified water. The rotary centrifugal design of the system also provides gas/liquid phase separation and liquid transport under microgravity conditions. A five-stage subsystem unit has been designed, built, delivered and integrated into the NASA JSC Advanced Water Recovery Systems Development Facility for performance testing. A major test objective of the project is to demonstrate the advancement of the CDS technology from the breadboard level to a subsystem level unit. An initial round of CDS performance testing was completed in fiscal year (FY) 2008. Based on FY08 testing, the system is now in development to support an Exploration Life Support (ELS) Project distillation comparison test expected to begin in early 2009. As part of the project objectives planned for FY09, the system will be reconfigured to support the ELS comparison test. The CDS will then be challenged with a series of human-gene-rated waste streams representative of those anticipated for a lunar outpost. This paper provides a description of the CDS technology, a status of the current project activities, and data on the system s performance to date.

Use of a remote clinical decision support service for a multicenter trial to implement prediction rules for children with minor blunt head trauma.

PubMed

Goldberg, Howard S; Paterno, Marilyn D; Grundmeier, Robert W; Rocha, Beatriz H; Hoffman, Jeffrey M; Tham, Eric; Swietlik, Marguerite; Schaeffer, Molly H; Pabbathi, Deepika; Deakyne, Sara J; Kuppermann, Nathan; Dayan, Peter S

2016-03-01

To evaluate the architecture, integration requirements, and execution characteristics of a remote clinical decision support (CDS) service used in a multicenter clinical trial. The trial tested the efficacy of implementing brain injury prediction rules for children with minor blunt head trauma. We integrated the Epic(®) electronic health record (EHR) with the Enterprise Clinical Rules Service (ECRS), a web-based CDS service, at two emergency departments. Patterns of CDS review included either a delayed, near-real-time review, where the physician viewed CDS recommendations generated by the nursing assessment, or a real-time review, where the physician viewed recommendations generated by their own documentation. A backstopping, vendor-based CDS triggered with zero delay when no recommendation was available in the EHR from the web-service. We assessed the execution characteristics of the integrated system and the source of the generated recommendations viewed by physicians. The ECRS mean execution time was 0.74 ±0.72 s. Overall execution time was substantially different at the two sites, with mean total transaction times of 19.67 and 3.99 s. Of 1930 analyzed transactions from the two sites, 60% (310/521) of all physician documentation-initiated recommendations and 99% (1390/1409) of all nurse documentation-initiated recommendations originated from the remote web service. The remote CDS system was the source of recommendations in more than half of the real-time cases and virtually all the near-real-time cases. Comparisons are limited by allowable variation in user workflow and resolution of the EHR clock. With maturation and adoption of standards for CDS services, remote CDS shows promise to decrease time-to-trial for multicenter evaluations of candidate decision support interventions. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Transforming user needs into functional requirements for an antibiotic clinical decision support system: explicating content analysis for system design.

PubMed

Bright, T J

2013-01-01

Many informatics studies use content analysis to generate functional requirements for system development. Explication of this translational process from qualitative data to functional requirements can strengthen the understanding and scientific rigor when applying content analysis in informatics studies. To describe a user-centered approach transforming emergent themes derived from focus group data into functional requirements for informatics solutions and to illustrate these methods to the development of an antibiotic clinical decision support system (CDS). THE APPROACH CONSISTED OF FIVE STEPS: 1) identify unmet therapeutic planning information needs via Focus Group Study-I, 2) develop a coding framework of therapeutic planning themes to refine the domain scope to antibiotic therapeutic planning, 3) identify functional requirements of an antibiotic CDS system via Focus Group Study-II, 4) discover informatics solutions and functional requirements from coded data, and 5) determine the types of information needed to support the antibiotic CDS system and link with the identified informatics solutions and functional requirements. The coding framework for Focus Group Study-I revealed unmet therapeutic planning needs. Twelve subthemes emerged and were clustered into four themes; analysis indicated a need for an antibiotic CDS intervention. Focus Group Study-II included five types of information needs. Comments from the Barrier/Challenge to information access and Function/Feature themes produced three informatics solutions and 13 functional requirements of an antibiotic CDS system. Comments from the Patient, Institution, and Domain themes generated required data elements for each informatics solution. This study presents one example explicating content analysis of focus group data and the analysis process to functional requirements from narrative data. Illustration of this 5-step method was used to develop an antibiotic CDS system, resolving unmet antibiotic prescribing needs. As a reusable approach, these techniques can be refined and applied to resolve unmet information needs with informatics interventions in additional domains.

Development of a SNOMED CT based national medication decision support system.

PubMed

Greibe, Kell

2013-01-01

Physicians often lack the time to familiarize themselves with the details of particular allergies or other drug restrictions. Clinical Decision Support (CDS), based on a structured terminology as SNOMED CT (SCT), can help physicians get an overview, by automatically alerting allergy, interactions and other important information. The centralized CDS platform based on SCT, controls Allergy, Interactions, Risk Situation Drugs and Max Dose restrictions by the help of databases developed for these specific purposes. The CDS will respond to automatic web service requests from the hospital or GP electronic medication system (EMS) during prescription, and return alerts and information. The CDS also contains a Physicians Preference Database where the physicians individually can set which kind of alerts they want to see. The result is clinically useful information physicians can use as a base for a more effective and safer treatment, without developing alert fatigue.

Enhancing Worker Health Through Clinical Decision Support (CDS): An Introduction to a Compilation.

PubMed

Filios, Margaret S; Storey, Eileen; Baron, Sherry; Luensman, Genevieve B; Shiffman, Richard N

2017-11-01

This article outlines an approach to developing clinical decision support (CDS) for conditions related to work and health. When incorporated in electronic health records, such CDS will assist primary care providers (PCPs) care for working patients. Three groups of Subject Matter Experts (SMEs) identified relevant clinical practice guidelines, best practices, and reviewed published literature concerning work-related asthma, return-to-work, and management of diabetes at work. SMEs developed one recommendation per topic that could be supported by electronic CDS. Reviews with PCPs, staff, and health information system implementers in five primary care settings confirmed that the approach was important and operationally sound. This compendium is intended to stimulate a dialogue between occupational health specialists and PCPs that will enhance the use of work information about patients in the primary care setting.

Enhancements in healthcare information technology systems: customizing vendor-supplied clinical decision support for a high-risk patient population.

PubMed

Tiwari, Ruchi; Tsapepas, Demetra S; Powell, Jaclyn T; Martin, Spencer T

2013-01-01

Healthcare organizations continue to adopt information technologies with clinical decision support (CDS) to prevent potential medication-related adverse drug events. End-users who are unfamiliar with certain high-risk patient populations are at an increased risk of unknowingly causing medication errors. The following case describes a heart transplant recipient exposed to supra-therapeutic concentrations of tacrolimus during co-administration of ritonavir as a result of vendor supplied CDS tools that omitted an interaction alert. After review of 4692 potential tacrolimus-based DDIs between 329 different drug pairs supplied by vendor CDS, the severity of 20 DDIs were downgraded and the severity of 62 were upgraded. The need for institution-specific customization of vendor-provided CDS is paramount to ensure avoidance of medication errors. Individualized care will become more important as patient populations and institutions become more specialized. In the future, vendors providing integrated CDS tools must be proactive in developing institution-specific and easily customizable CDS tools.

Enhancements in healthcare information technology systems: customizing vendor-supplied clinical decision support for a high-risk patient population

PubMed Central

Tiwari, Ruchi; Tsapepas, Demetra S; Powell, Jaclyn T

2013-01-01

Healthcare organizations continue to adopt information technologies with clinical decision support (CDS) to prevent potential medication-related adverse drug events. End-users who are unfamiliar with certain high-risk patient populations are at an increased risk of unknowingly causing medication errors. The following case describes a heart transplant recipient exposed to supra-therapeutic concentrations of tacrolimus during co-administration of ritonavir as a result of vendor supplied CDS tools that omitted an interaction alert. After review of 4692 potential tacrolimus-based DDIs between 329 different drug pairs supplied by vendor CDS, the severity of 20 DDIs were downgraded and the severity of 62 were upgraded. The need for institution-specific customization of vendor-provided CDS is paramount to ensure avoidance of medication errors. Individualized care will become more important as patient populations and institutions become more specialized. In the future, vendors providing integrated CDS tools must be proactive in developing institution-specific and easily customizable CDS tools. PMID:22813760

Transforming User Needs into Functional Requirements for an Antibiotic Clinical Decision Support System

PubMed Central

Bright, T.J.

2013-01-01

Summary Background Many informatics studies use content analysis to generate functional requirements for system development. Explication of this translational process from qualitative data to functional requirements can strengthen the understanding and scientific rigor when applying content analysis in informatics studies. Objective To describe a user-centered approach transforming emergent themes derived from focus group data into functional requirements for informatics solutions and to illustrate these methods to the development of an antibiotic clinical decision support system (CDS). Methods The approach consisted of five steps: 1) identify unmet therapeutic planning information needs via Focus Group Study-I, 2) develop a coding framework of therapeutic planning themes to refine the domain scope to antibiotic therapeutic planning, 3) identify functional requirements of an antibiotic CDS system via Focus Group Study-II, 4) discover informatics solutions and functional requirements from coded data, and 5) determine the types of information needed to support the antibiotic CDS system and link with the identified informatics solutions and functional requirements. Results The coding framework for Focus Group Study-I revealed unmet therapeutic planning needs. Twelve subthemes emerged and were clustered into four themes; analysis indicated a need for an antibiotic CDS intervention. Focus Group Study-II included five types of information needs. Comments from the Barrier/Challenge to information access and Function/Feature themes produced three informatics solutions and 13 functional requirements of an antibiotic CDS system. Comments from the Patient, Institution, and Domain themes generated required data elements for each informatics solution. Conclusion This study presents one example explicating content analysis of focus group data and the analysis process to functional requirements from narrative data. Illustration of this 5-step method was used to develop an antibiotic CDS system, resolving unmet antibiotic prescribing needs. As a reusable approach, these techniques can be refined and applied to resolve unmet information needs with informatics interventions in additional domains. PMID:24454586

Development of an Exploration-Class Cascade Distillation System: Flight Like Prototype Design Status

NASA Technical Reports Server (NTRS)

Sargusingh, Miriam C.; Callahan, Michael R.

2016-01-01

The ability to recover and purify water through physiochemical processes is crucial for realizing long-term human space missions, including both planetary habitation and space travel. Because of their robust nature, distillation systems have been actively pursued as one of the technologies for water recovery. One such technology is the Cascade Distillation System (CDS) a multi-stage vacuum rotary distiller system designed to recover water in a microgravity environment. The CDS provides a similar function to the state of the art (SOA) vapor compressor distiller (VCD) currently employed on the International Space Station, but its control scheme and ancillary components are judged to be more straightforward and simpler to implement into a more reliable and efficient system. Through the Advanced Exploration Systems (AES) Life Support Systems (LSS) Project, the NASA Johnson Space Center (JSC) in collaboration with Honeywell International is developing a second generation flight forward prototype (CDS 2.0). A preliminary design fo the CDS 2.0 was presented to the project in September 2014. Following this review, detailed design of the system continued. The existing ground test prototype was used as a platform to demonstrate key 2.0 design and operational concepts to support this effort and mitigate design risk. A volumetric prototype was also developed to evaluate the packaging design for operability and maintainability. The updated system design was reviewed by the AES LSS Project and other key stakeholders in September 2015. This paper details the status of the CDS 2.0 design.

A systematic review of near real-time and point-of-care clinical decision support in anesthesia information management systems.

PubMed

Simpao, Allan F; Tan, Jonathan M; Lingappan, Arul M; Gálvez, Jorge A; Morgan, Sherry E; Krall, Michael A

2017-10-01

Anesthesia information management systems (AIMS) are sophisticated hardware and software technology solutions that can provide electronic feedback to anesthesia providers. This feedback can be tailored to provide clinical decision support (CDS) to aid clinicians with patient care processes, documentation compliance, and resource utilization. We conducted a systematic review of peer-reviewed articles on near real-time and point-of-care CDS within AIMS using the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Studies were identified by searches of the electronic databases Medline and EMBASE. Two reviewers screened studies based on title, abstract, and full text. Studies that were similar in intervention and desired outcome were grouped into CDS categories. Three reviewers graded the evidence within each category. The final analysis included 25 articles on CDS as implemented within AIMS. CDS categories included perioperative antibiotic prophylaxis, post-operative nausea and vomiting prophylaxis, vital sign monitors and alarms, glucose management, blood pressure management, ventilator management, clinical documentation, and resource utilization. Of these categories, the reviewers graded perioperative antibiotic prophylaxis and clinical documentation as having strong evidence per the peer reviewed literature. There is strong evidence for the inclusion of near real-time and point-of-care CDS in AIMS to enhance compliance with perioperative antibiotic prophylaxis and clinical documentation. Additional research is needed in many other areas of AIMS-based CDS.

Evaluation of the Effect of Decision Support on the Efficiency of Primary Care Providers in the Outpatient Practice

PubMed Central

Hankey, Ronald A.; Decker, Lindsay K.; Cha, Stephen S.; Greenes, Robert A.; Liu, Hongfang; Chaudhry, Rajeev

2015-01-01

Background: Clinical decision support (CDS) for primary care has been shown to improve delivery of preventive services. However, there is little evidence for efficiency of physicians due to CDS assistance. In this article, we report a pilot study for measuring the impact of CDS on the time spent by physicians for deciding on preventive services and chronic disease management. Methods: We randomly selected 30 patients from a primary care practice, and assigned them to 10 physicians. The physicians were requested to perform chart review to decide on preventive services and chronic disease management for the assigned patients. The patients assignment was done in a randomized crossover design, such that each patient received 2 sets of recommendations—one from a physician with CDS assistance and the other from a different physician without CDS assistance. We compared the physician recommendations made using CDS assistance, with the recommendations made without CDS assistance. Results: The physicians required an average of 1 minute 44 seconds, when they were they had access to the decision support system and 5 minutes when they were unassisted. Hence the CDS assistance resulted in an estimated saving of 3 minutes 16 seconds (65%) of the physicians’ time, which was statistically significant (P < .0001). There was no statistically significant difference in the number of recommendations. Conclusion: Our findings suggest that CDS assistance significantly reduced the time spent by physicians for deciding on preventive services and chronic disease management. The result needs to be confirmed by performing similar studies at other institutions. PMID:25155103

Developing an Interactive Data Visualization Tool to Assess the Impact of Decision Support on Clinical Operations.

PubMed

Huber, Timothy C; Krishnaraj, Arun; Monaghan, Dayna; Gaskin, Cree M

2018-05-18

Due to mandates from recent legislation, clinical decision support (CDS) software is being adopted by radiology practices across the country. This software provides imaging study decision support for referring providers at the point of order entry. CDS systems produce a large volume of data, providing opportunities for research and quality improvement. In order to better visualize and analyze trends in this data, an interactive data visualization dashboard was created using a commercially available data visualization platform. Following the integration of a commercially available clinical decision support product into the electronic health record, a dashboard was created using a commercially available data visualization platform (Tableau, Seattle, WA). Data generated by the CDS were exported from the data warehouse, where they were stored, into the platform. This allowed for real-time visualization of the data generated by the decision support software. The creation of the dashboard allowed the output from the CDS platform to be more easily analyzed and facilitated hypothesis generation. Integrating data visualization tools into clinical decision support tools allows for easier data analysis and can streamline research and quality improvement efforts.

Key principles for a national clinical decision support knowledge sharing framework: synthesis of insights from leading subject matter experts.

PubMed

Kawamoto, Kensaku; Hongsermeier, Tonya; Wright, Adam; Lewis, Janet; Bell, Douglas S; Middleton, Blackford

2013-01-01

To identify key principles for establishing a national clinical decision support (CDS) knowledge sharing framework. As part of an initiative by the US Office of the National Coordinator for Health IT (ONC) to establish a framework for national CDS knowledge sharing, key stakeholders were identified. Stakeholders' viewpoints were obtained through surveys and in-depth interviews, and findings and relevant insights were summarized. Based on these insights, key principles were formulated for establishing a national CDS knowledge sharing framework. Nineteen key stakeholders were recruited, including six executives from electronic health record system vendors, seven executives from knowledge content producers, three executives from healthcare provider organizations, and three additional experts in clinical informatics. Based on these stakeholders' insights, five key principles were identified for effectively sharing CDS knowledge nationally. These principles are (1) prioritize and support the creation and maintenance of a national CDS knowledge sharing framework; (2) facilitate the development of high-value content and tooling, preferably in an open-source manner; (3) accelerate the development or licensing of required, pragmatic standards; (4) acknowledge and address medicolegal liability concerns; and (5) establish a self-sustaining business model. Based on the principles identified, a roadmap for national CDS knowledge sharing was developed through the ONC's Advancing CDS initiative. The study findings may serve as a useful guide for ongoing activities by the ONC and others to establish a national framework for sharing CDS knowledge and improving clinical care.

A pilot study of distributed knowledge management and clinical decision support in the cloud.

PubMed

Dixon, Brian E; Simonaitis, Linas; Goldberg, Howard S; Paterno, Marilyn D; Schaeffer, Molly; Hongsermeier, Tonya; Wright, Adam; Middleton, Blackford

2013-09-01

Implement and perform pilot testing of web-based clinical decision support services using a novel framework for creating and managing clinical knowledge in a distributed fashion using the cloud. The pilot sought to (1) develop and test connectivity to an external clinical decision support (CDS) service, (2) assess the exchange of data to and knowledge from the external CDS service, and (3) capture lessons to guide expansion to more practice sites and users. The Clinical Decision Support Consortium created a repository of shared CDS knowledge for managing hypertension, diabetes, and coronary artery disease in a community cloud hosted by Partners HealthCare. A limited data set for primary care patients at a separate health system was securely transmitted to a CDS rules engine hosted in the cloud. Preventive care reminders triggered by the limited data set were returned for display to clinician end users for review and display. During a pilot study, we (1) monitored connectivity and system performance, (2) studied the exchange of data and decision support reminders between the two health systems, and (3) captured lessons. During the six month pilot study, there were 1339 patient encounters in which information was successfully exchanged. Preventive care reminders were displayed during 57% of patient visits, most often reminding physicians to monitor blood pressure for hypertensive patients (29%) and order eye exams for patients with diabetes (28%). Lessons learned were grouped into five themes: performance, governance, semantic interoperability, ongoing adjustments, and usability. Remote, asynchronous cloud-based decision support performed reasonably well, although issues concerning governance, semantic interoperability, and usability remain key challenges for successful adoption and use of cloud-based CDS that will require collaboration between biomedical informatics and computer science disciplines. Decision support in the cloud is feasible and may be a reasonable path toward achieving better support of clinical decision-making across the widest range of health care providers. Published by Elsevier B.V.

Publication, discovery and interoperability of Clinical Decision Support Systems: A Linked Data approach.

PubMed

Marco-Ruiz, Luis; Pedrinaci, Carlos; Maldonado, J A; Panziera, Luca; Chen, Rong; Bellika, J Gustav

2016-08-01

The high costs involved in the development of Clinical Decision Support Systems (CDSS) make it necessary to share their functionality across different systems and organizations. Service Oriented Architectures (SOA) have been proposed to allow reusing CDSS by encapsulating them in a Web service. However, strong barriers in sharing CDS functionality are still present as a consequence of lack of expressiveness of services' interfaces. Linked Services are the evolution of the Semantic Web Services paradigm to process Linked Data. They aim to provide semantic descriptions over SOA implementations to overcome the limitations derived from the syntactic nature of Web services technologies. To facilitate the publication, discovery and interoperability of CDS services by evolving them into Linked Services that expose their interfaces as Linked Data. We developed methods and models to enhance CDS SOA as Linked Services that define a rich semantic layer based on machine interpretable ontologies that powers their interoperability and reuse. These ontologies provided unambiguous descriptions of CDS services properties to expose them to the Web of Data. We developed models compliant with Linked Data principles to create a semantic representation of the components that compose CDS services. To evaluate our approach we implemented a set of CDS Linked Services using a Web service definition ontology. The definitions of Web services were linked to the models developed in order to attach unambiguous semantics to the service components. All models were bound to SNOMED-CT and public ontologies (e.g. Dublin Core) in order to count on a lingua franca to explore them. Discovery and analysis of CDS services based on machine interpretable models was performed reasoning over the ontologies built. Linked Services can be used effectively to expose CDS services to the Web of Data by building on current CDS standards. This allows building shared Linked Knowledge Bases to provide machine interpretable semantics to the CDS service description alleviating the challenges on interoperability and reuse. Linked Services allow for building 'digital libraries' of distributed CDS services that can be hosted and maintained in different organizations. Copyright © 2016 Elsevier Inc. All rights reserved.

Automated recommendation for cervical cancer screening and surveillance.

PubMed

Wagholikar, Kavishwar B; MacLaughlin, Kathy L; Casey, Petra M; Kastner, Thomas M; Henry, Michael R; Hankey, Ronald A; Peters, Steve G; Greenes, Robert A; Chute, Christopher G; Liu, Hongfang; Chaudhry, Rajeev

2014-01-01

Because of the complexity of cervical cancer prevention guidelines, clinicians often fail to follow best-practice recommendations. Moreover, existing clinical decision support (CDS) systems generally recommend a cervical cytology every three years for all female patients, which is inappropriate for patients with abnormal findings that require surveillance at shorter intervals. To address this problem, we developed a decision tree-based CDS system that integrates national guidelines to provide comprehensive guidance to clinicians. Validation was performed in several iterations by comparing recommendations generated by the system with those of clinicians for 333 patients. The CDS system extracted relevant patient information from the electronic health record and applied the guideline model with an overall accuracy of 87%. Providers without CDS assistance needed an average of 1 minute 39 seconds to decide on recommendations for management of abnormal findings. Overall, our work demonstrates the feasibility and potential utility of automated recommendation system for cervical cancer screening and surveillance.

Governance for clinical decision support: case studies and recommended practices from leading institutions

PubMed Central

Sittig, Dean F; Ash, Joan S; Bates, David W; Feblowitz, Joshua; Fraser, Greg; Maviglia, Saverio M; McMullen, Carmit; Nichol, W Paul; Pang, Justine E; Starmer, Jack; Middleton, Blackford

2011-01-01

Objective Clinical decision support (CDS) is a powerful tool for improving healthcare quality and ensuring patient safety; however, effective implementation of CDS requires effective clinical and technical governance structures. The authors sought to determine the range and variety of these governance structures and identify a set of recommended practices through observational study. Design Three site visits were conducted at institutions across the USA to learn about CDS capabilities and processes from clinical, technical, and organizational perspectives. Based on the results of these visits, written questionnaires were sent to the three institutions visited and two additional sites. Together, these five organizations encompass a variety of academic and community hospitals as well as small and large ambulatory practices. These organizations use both commercially available and internally developed clinical information systems. Measurements Characteristics of clinical information systems and CDS systems used at each site as well as governance structures and content management approaches were identified through extensive field interviews and follow-up surveys. Results Six recommended practices were identified in the area of governance, and four were identified in the area of content management. Key similarities and differences between the organizations studied were also highlighted. Conclusion Each of the five sites studied contributed to the recommended practices presented in this paper for CDS governance. Since these strategies appear to be useful at a diverse range of institutions, they should be considered by any future implementers of decision support. PMID:21252052

Improving Performance on Preventive Health Quality Measures Using Clinical Decision Support to Capture Care Done Elsewhere and Patient Exceptions.

PubMed

Bowen, Michael E; Bhat, Deepa; Fish, Jason; Moran, Brett; Howell-Stampley, Temple; Kirk, Lynne; Persell, Stephen D; Halm, Ethan A

Preventive services required for performance measurement often are completed in outside health systems and not captured in electronic medical records (EMRs). A before-after study was conducted to examine the ability of clinical decision support (CDS) to improve performance on preventive quality measures, capture clinician-reported services completed elsewhere, and patient/medical exceptions and to describe their impact on quality measurement. CDS improved performance on colorectal cancer screening, osteoporosis screening, and pneumococcal vaccination measures ( P < .05) but not breast or cervical cancer screening. CDS captured clinician-reported services completed elsewhere (2% to 10%) and patient/medical exceptions (<3%). Compared to measures using only within-system data, including services completed elsewhere in the numerator improved performance: pneumococcal vaccine (73% vs 82%); breast (69% vs 75%), colorectal (58% vs 70%), and cervical cancer (53% vs 62%); and osteoporosis (72% vs 75%) screening ( P < .05). Visit-based CDS can capture clinician-reported preventive services, and accounting for services completed elsewhere improves performance on quality measures.

Key principles for a national clinical decision support knowledge sharing framework: synthesis of insights from leading subject matter experts

PubMed Central

Hongsermeier, Tonya; Wright, Adam; Lewis, Janet; Bell, Douglas S; Middleton, Blackford

2013-01-01

Objective To identify key principles for establishing a national clinical decision support (CDS) knowledge sharing framework. Materials and methods As part of an initiative by the US Office of the National Coordinator for Health IT (ONC) to establish a framework for national CDS knowledge sharing, key stakeholders were identified. Stakeholders' viewpoints were obtained through surveys and in-depth interviews, and findings and relevant insights were summarized. Based on these insights, key principles were formulated for establishing a national CDS knowledge sharing framework. Results Nineteen key stakeholders were recruited, including six executives from electronic health record system vendors, seven executives from knowledge content producers, three executives from healthcare provider organizations, and three additional experts in clinical informatics. Based on these stakeholders' insights, five key principles were identified for effectively sharing CDS knowledge nationally. These principles are (1) prioritize and support the creation and maintenance of a national CDS knowledge sharing framework; (2) facilitate the development of high-value content and tooling, preferably in an open-source manner; (3) accelerate the development or licensing of required, pragmatic standards; (4) acknowledge and address medicolegal liability concerns; and (5) establish a self-sustaining business model. Discussion Based on the principles identified, a roadmap for national CDS knowledge sharing was developed through the ONC's Advancing CDS initiative. Conclusion The study findings may serve as a useful guide for ongoing activities by the ONC and others to establish a national framework for sharing CDS knowledge and improving clinical care. PMID:22865671

Cascade Distillation System Design for Safety and Mission Assurance

NASA Technical Reports Server (NTRS)

Sargusingh, Miriam J.; Callahan, Michael R.

2015-01-01

Per the NASA Human Health, Life Support and Habitation System Technology Area 06 report "crewed missions venturing beyond Low-Earth Orbit (LEO) will require technologies with improved reliability, reduced mass, self-sufficiency, and minimal logistical needs as an emergency or quick-return option will not be feasible." To meet this need, the development team of the second generation Cascade Distillation System (CDS 2.0) opted a development approach that explicitely incorporate consideration of safety, mission assurance, and autonomy. The CDS 2.0 prelimnary design focused on establishing a functional baseline that meets the CDS core capabilities and performance. The critical design phase is now focused on incorporating features through a deliberative process of establishing the systems failure modes and effects, identifying mitigative strategies, and evaluating the merit of the proposed actions through analysis and test. This paper details results of this effort on the CDS 2.0 design.

Cascade Distillation System Design for Safety and Mission Assurance

NASA Technical Reports Server (NTRS)

Sarguisingh, Miriam; Callahan, Michael R.; Okon, Shira

2015-01-01

Per the NASA Human Health, Life Support and Habitation System Technology Area 06 report "crewed missions venturing beyond Low-Earth Orbit (LEO) will require technologies with improved reliability, reduced mass, self-sufficiency, and minimal logistical needs as an emergency or quick-return option will not be feasible".1 To meet this need, the development team of the second generation Cascade Distillation System (CDS 2.0) chose a development approach that explicitly incorporate consideration of safety, mission assurance, and autonomy. The CDS 2.0 preliminary design focused on establishing a functional baseline that meets the CDS core capabilities and performance. The critical design phase is now focused on incorporating features through a deliberative process of establishing the systems failure modes and effects, identifying mitigation strategies, and evaluating the merit of the proposed actions through analysis and test. This paper details results of this effort on the CDS 2.0 design.

Cascade Distillation Subsystem Development: Early Results From the Exploration Life Support Distillation Technology Comparison Test

NASA Technical Reports Server (NTRS)

Callahan, Michael R.; Patel, Vipul; Pickering, Karen D.

2009-01-01

In 2009, the Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell International, Torrance, CA) was assessed in the National Aeronautics and Space Administration (NASA) Exploration Life Support (ELS) distillation comparison test. The purpose of the test was to collect data to support down-selection and development of a primary distillation technology for application in a lunar outpost water recovery system. The CDS portion of the comparison test was conducted between May 6 and August 19, 2009. The system was challenged with two pretreated test solutions, each intended to represent a feasible wastewater generated in a surface habitat. The 30-day equivalent wastewater loading volume for a crew of four was processed for each wastewater solution. Test Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. Test Solution 2 contained the addition of human-generated hygiene wastewater to the solution 1 waste stream components. Approximately 1500 kg of total wastewater was processed through the CDS during testing. Respective recoveries per solution were 93.4 +/- 0.7 and 90.3 +/- 0.5%. The average specific energy of the system was calculated to be less than 130 W-hr/kg. The following paper provides detailed information and data on the performance of the CDS as challenged per the ELS distillation comparison test.

Influencing Anesthesia Provider Behavior Using Anesthesia Information Management System Data for Near Real-Time Alerts and Post Hoc Reports.

PubMed

Epstein, Richard H; Dexter, Franklin; Patel, Neil

2015-09-01

In this review article, we address issues related to using data from anesthesia information management systems (AIMS) to deliver near real-time alerts via AIMS workstation popups and/or alphanumeric pagers and post hoc reports via e-mail. We focus on reports and alerts for influencing the behavior of anesthesia providers (i.e., anesthesiologists, anesthesia residents, and nurse anesthetists). Multiple studies have shown that anesthesia clinical decision support (CDS) improves adherence to protocols and increases financial performance through facilitation of billing, regulatory, and compliance documentation; however, improved clinical outcomes have not been demonstrated. We inform developers and users of feedback systems about the multitude of concerns to consider during development and implementation of CDS to increase its effectiveness and to mitigate its potentially disruptive aspects. We discuss the timing and modalities used to deliver messages, implications of outlier-only versus individualized feedback, the need to consider possible unintended consequences of such feedback, regulations, sustainability, and portability among systems. We discuss statistical issues related to the appropriate evaluation of CDS efficacy. We provide a systematic review of the published literature (indexed in PubMed) of anesthesia CDS and offer 2 case studies of CDS interventions using AIMS data from our own institution illustrating the salient points. Because of the considerable expense and complexity of maintaining near real-time CDS systems, as compared with providing individual reports via e-mail after the fact, we suggest that if the same goal can be accomplished via delayed reporting versus immediate feedback, the former approach is preferable. Nevertheless, some processes require near real-time alerts to produce the desired improvement. Post hoc e-mail reporting from enterprise-wide electronic health record systems is straightforward and can be accomplished using system-independent pathways (e.g., via built-in e-mail support provided by the relational database management system). However, for some of these enterprise-wide systems, near real-time data access, necessary for CDS that generates concurrent alerts, has been challenging to implement.

Design of decision support interventions for medication prescribing.

PubMed

Horsky, Jan; Phansalkar, Shobha; Desai, Amrita; Bell, Douglas; Middleton, Blackford

2013-06-01

Describe optimal design attributes of clinical decision support (CDS) interventions for medication prescribing, emphasizing perceptual, cognitive and functional characteristics that improve human-computer interaction (HCI) and patient safety. Findings from published reports on success, failures and lessons learned during implementation of CDS systems were reviewed and interpreted with regard to HCI and software usability principles. We then formulated design recommendations for CDS alerts that would reduce unnecessary workflow interruptions and allow clinicians to make informed decisions quickly, accurately and without extraneous cognitive and interactive effort. Excessive alerting that tends to distract clinicians rather than provide effective CDS can be reduced by designing only high severity alerts as interruptive dialog boxes and less severe warnings without explicit response requirement, by curating system knowledge bases to suppress warnings with low clinical utility and by integrating contextual patient data into the decision logic. Recommended design principles include parsimonious and consistent use of color and language, minimalist approach to the layout of information and controls, the use of font attributes to convey hierarchy and visual prominence of important data over supporting information, the inclusion of relevant patient data in the context of the alert and allowing clinicians to respond with one or two clicks. Although HCI and usability principles are well established and robust, CDS and EHR system interfaces rarely conform to the best known design conventions and are seldom conceived and designed well enough to be truly versatile and dependable tools. These relatively novel interventions still require careful monitoring, research and analysis of its track record to mature. Clarity and specificity of alert content and optimal perceptual and cognitive attributes, for example, are essential for providing effective decision support to clinicians. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Grand Challenges in Clinical Decision Support v10

PubMed Central

Sittig, Dean F.; Wright, Adam; Osheroff, Jerome A.; Middleton, Blackford; Teich, Jonathan M.; Ash, Joan S.; Campbell, Emily; Bates, David W.

2008-01-01

There is a pressing need for high-quality, effective means of designing, developing, presenting, implementing, evaluating, and maintaining all types of clinical decision support capabilities for clinicians, patients and consumers. Using an iterative, consensus-building process we identified a rank-ordered list of the top 10 grand challenges in clinical decision support. This list was created to educate and inspire researchers, developers, funders, and policy-makers. The list of challenges in order of importance that they be solved if patients and organizations are to begin realizing the fullest benefits possible of these systems consists of: Improve the human-computer interface; Disseminate best practices in CDS design, development, and implementation; Summarize patient-level information; Prioritize and filter recommendations to the user; Create an architecture for sharing executable CDS modules and services; Combine recommendations for patients with co-morbidities; Prioritize CDS content development and implementation; Create internet-accessible clinical decision support repositories; Use freetext information to drive clinical decision support; Mine large clinical databases to create new CDS. Identification of solutions to these challenges is critical if clinical decision support is to achieve its potential and improve the quality, safety and efficiency of healthcare. PMID:18029232

Making pharmacogenomic-based prescribing alerts more effective: A scenario-based pilot study with physicians.

PubMed

Overby, Casey Lynnette; Devine, Emily Beth; Abernethy, Neil; McCune, Jeannine S; Tarczy-Hornoch, Peter

2015-06-01

To facilitate personalized drug dosing (PDD), this pilot study explored the communication effectiveness and clinical impact of using a prototype clinical decision support (CDS) system embedded in an electronic health record (EHR) to deliver pharmacogenomic (PGx) information to physicians. We employed a conceptual framework and measurement model to access the impact of physician characteristics (previous experience, awareness, relative advantage, perceived usefulness), technology characteristics (methods of implementation-semi-active/active, actionability-low/high) and a task characteristic (drug prescribed) on communication effectiveness (usefulness, confidence in prescribing decision), and clinical impact (uptake, prescribing intent, change in drug dosing). Physicians performed prescribing tasks using five simulated clinical case scenarios, presented in random order within the prototype PGx-CDS system. Twenty-two physicians completed the study. The proportion of physicians that saw a relative advantage to using PGx-CDS was 83% at the start and 94% at the conclusion of our study. Physicians used semi-active alerts 74-88% of the time. There was no association between previous experience with, awareness of, and belief in a relative advantage of using PGx-CDS and improved uptake. The proportion of physicians reporting confidence in their prescribing decisions decreased significantly after using the prototype PGx-CDS system (p=0.02). Despite decreases in confidence, physicians perceived a relative advantage to using PGx-CDS, viewed semi-active alerts on most occasions, and more frequently changed doses toward doses supported by published evidence. Specifically, sixty-five percent of physicians reduced their dosing, significantly for capecitabine (p=0.002) and mercaptopurine/thioguanine (p=0.03). These findings suggest a need to improve our prototype such that PGx CDS content is more useful and delivered in a way that improves physician's confidence in their prescribing decisions. The greatest increases in communication effectiveness and clinical impact of PGx-CDS are likely to be realized through continued focus on content, content delivery, and tailoring to physician characteristics. Copyright © 2015 Elsevier Inc. All rights reserved.

Clinical decision support improves quality of telephone triage documentation - an analysis of triage documentation before and after computerized clinical decision support

PubMed Central

2014-01-01

Background Clinical decision support (CDS) has been shown to be effective in improving medical safety and quality but there is little information on how telephone triage benefits from CDS. The aim of our study was to compare triage documentation quality associated with the use of a clinical decision support tool, ExpertRN©. Methods We examined 50 triage documents before and after a CDS tool was used in nursing triage. To control for the effects of CDS training we had an additional control group of triage documents created by nurses who were trained in the CDS tool, but who did not use it in selected notes. The CDS intervention cohort of triage notes was compared to both the pre-CDS notes and the CDS trained (but not using CDS) cohort. Cohorts were compared using the documentation standards of the American Academy of Ambulatory Care Nursing (AAACN). We also compared triage note content (documentation of associated positive and negative features relating to the symptoms, self-care instructions, and warning signs to watch for), and documentation defects pertinent to triage safety. Results Three of five AAACN documentation standards were significantly improved with CDS. There was a mean of 36.7 symptom features documented in triage notes for the CDS group but only 10.7 symptom features in the pre-CDS cohort (p < 0.0001) and 10.2 for the cohort that was CDS-trained but not using CDS (p < 0.0001). The difference between the mean of 10.2 symptom features documented in the pre-CDS and the mean of 10.7 symptom features documented in the CDS-trained but not using was not statistically significant (p = 0.68). Conclusions CDS significantly improves triage note documentation quality. CDS-aided triage notes had significantly more information about symptoms, warning signs and self-care. The changes in triage documentation appeared to be the result of the CDS alone and not due to any CDS training that came with the CDS intervention. Although this study shows that CDS can improve documentation, further study is needed to determine if it results in improved care. PMID:24645674

Clinical decision support improves quality of telephone triage documentation--an analysis of triage documentation before and after computerized clinical decision support.

PubMed

North, Frederick; Richards, Debra D; Bremseth, Kimberly A; Lee, Mary R; Cox, Debra L; Varkey, Prathibha; Stroebel, Robert J

2014-03-20

Clinical decision support (CDS) has been shown to be effective in improving medical safety and quality but there is little information on how telephone triage benefits from CDS. The aim of our study was to compare triage documentation quality associated with the use of a clinical decision support tool, ExpertRN©. We examined 50 triage documents before and after a CDS tool was used in nursing triage. To control for the effects of CDS training we had an additional control group of triage documents created by nurses who were trained in the CDS tool, but who did not use it in selected notes. The CDS intervention cohort of triage notes was compared to both the pre-CDS notes and the CDS trained (but not using CDS) cohort. Cohorts were compared using the documentation standards of the American Academy of Ambulatory Care Nursing (AAACN). We also compared triage note content (documentation of associated positive and negative features relating to the symptoms, self-care instructions, and warning signs to watch for), and documentation defects pertinent to triage safety. Three of five AAACN documentation standards were significantly improved with CDS. There was a mean of 36.7 symptom features documented in triage notes for the CDS group but only 10.7 symptom features in the pre-CDS cohort (p < 0.0001) and 10.2 for the cohort that was CDS-trained but not using CDS (p < 0.0001). The difference between the mean of 10.2 symptom features documented in the pre-CDS and the mean of 10.7 symptom features documented in the CDS-trained but not using was not statistically significant (p = 0.68). CDS significantly improves triage note documentation quality. CDS-aided triage notes had significantly more information about symptoms, warning signs and self-care. The changes in triage documentation appeared to be the result of the CDS alone and not due to any CDS training that came with the CDS intervention. Although this study shows that CDS can improve documentation, further study is needed to determine if it results in improved care.

Computerized Design Synthesis (CDS), A database-driven multidisciplinary design tool

NASA Technical Reports Server (NTRS)

Anderson, D. M.; Bolukbasi, A. O.

1989-01-01

The Computerized Design Synthesis (CDS) system under development at McDonnell Douglas Helicopter Company (MDHC) is targeted to make revolutionary improvements in both response time and resource efficiency in the conceptual and preliminary design of rotorcraft systems. It makes the accumulated design database and supporting technology analysis results readily available to designers and analysts of technology, systems, and production, and makes powerful design synthesis software available in a user friendly format.

Immobilization of CdS nanoparticles formed in reverse micelles onto aluminosilicate supports and their photocatalytic properties.

PubMed

Hirai, Takayuki; Bando, Yoko

2005-08-15

CdS nanoparticles, prepared in reverse micellar system, were immobilized onto thiol-modified aluminosilicate particles (ASSH) by a simple operation: addition of ASSH in the micellar solution and mild stirring. The resulting CdS nanoparticles-aluminosilicate composites (ASCdS) were used as photocatalysts for H2 generation from 2-propanol aqueous solution. The chemical properties of the aluminosilicate, such as affinity for water and other reactants, were found to affect the photocatalytic property of the CdS nanoparticles immobilized. Zeolite particles, having affinity for water and 2-propanol, gave a good ASCdS photocatalyst with respect to H2 generation.

Cooperative Data Sharing: Simple Support for Clusters of SMP Nodes

NASA Technical Reports Server (NTRS)

DiNucci, David C.; Balley, David H. (Technical Monitor)

1997-01-01

Libraries like PVM and MPI send typed messages to allow for heterogeneous cluster computing. Lower-level libraries, such as GAM, provide more efficient access to communication by removing the need to copy messages between the interface and user space in some cases. still lower-level interfaces, such as UNET, get right down to the hardware level to provide maximum performance. However, these are all still interfaces for passing messages from one process to another, and have limited utility in a shared-memory environment, due primarily to the fact that message passing is just another term for copying. This drawback is made more pertinent by today's hybrid architectures (e.g. clusters of SMPs), where it is difficult to know beforehand whether two communicating processes will share memory. As a result, even portable language tools (like HPF compilers) must either map all interprocess communication, into message passing with the accompanying performance degradation in shared memory environments, or they must check each communication at run-time and implement the shared-memory case separately for efficiency. Cooperative Data Sharing (CDS) is a single user-level API which abstracts all communication between processes into the sharing and access coordination of memory regions, in a model which might be described as "distributed shared messages" or "large-grain distributed shared memory". As a result, the user programs to a simple latency-tolerant abstract communication specification which can be mapped efficiently to either a shared-memory or message-passing based run-time system, depending upon the available architecture. Unlike some distributed shared memory interfaces, the user still has complete control over the assignment of data to processors, the forwarding of data to its next likely destination, and the queuing of data until it is needed, so even the relatively high latency present in clusters can be accomodated. CDS does not require special use of an MMU, which can add overhead to some DSM systems, and does not require an SPMD programming model. unlike some message-passing interfaces, CDS allows the user to implement efficient demand-driven applications where processes must "fight" over data, and does not perform copying if processes share memory and do not attempt concurrent writes. CDS also supports heterogeneous computing, dynamic process creation, handlers, and a very simple thread-arbitration mechanism. Additional support for array subsections is currently being considered. The CDS1 API, which forms the kernel of CDS, is built primarily upon only 2 communication primitives, one process initiation primitive, and some data translation (and marshalling) routines, memory allocation routines, and priority control routines. The entire current collection of 28 routines provides enough functionality to implement most (or all) of MPI 1 and 2, which has a much larger interface consisting of hundreds of routines. still, the API is small enough to consider integrating into standard os interfaces for handling inter-process communication in a network-independent way. This approach would also help to solve many of the problems plaguing other higher-level standards such as MPI and PVM which must, in some cases, "play OS" to adequately address progress and process control issues. The CDS2 API, a higher level of interface roughly equivalent in functionality to MPI and to be built entirely upon CDS1, is still being designed. It is intended to add support for the equivalent of communicators, reduction and other collective operations, process topologies, additional support for process creation, and some automatic memory management. CDS2 will not exactly match MPI, because the copy-free semantics of communication from CDS1 will be supported. CDS2 application programs will be free to carefully also use CDS1. CDS1 has been implemented on networks of workstations running unmodified Unix-based operating systems, using UDP/IP and vendor-supplied high- performance locks. Although its inter-node performance is currently unimpressive due to rudimentary implementation technique, it even now outperforms highly-optimized MPI implementation on intra-node communication due to its support for non-copy communication. The similarity of the CDS1 architecture to that of other projects such as UNET and TRAP suggests that the inter-node performance can be increased significantly to surpass MPI or PVM, and it may be possible to migrate some of its functionality to communication controllers.

Thermodynamic Analyses of the LCLS-II Cryogenic Distribution System

DOE PAGES

Dalesandro, Andrew; Kaluzny, Joshua; Klebaner, Arkadiy

2016-12-29

The Linac Coherent Light Source (LCLS) at Stanford Linear Accelerator Center (SLAC) is in the process of being upgraded to a superconducting radio frequency (SRF) accelerator and renamed LCLS-II. This upgrade requires thirty-five 1.3 GHz SRF cryomodules (CM) and two 3.9 GHz CM. A cryogenic distribution system (CDS) is in development by Fermi National Accelerator Laboratory to interconnect the CM Linac with the cryogenic plant (CP). The CDS design utilizes cryogenic helium to support the CM operations with a high temperature thermal shield around 55 K, a low temperature thermal intercepts around 5 K, and a SRF cavity liquid heliummore » supply and sub-atmospheric vapor return both around 2 K. Additionally the design must accommodate a Linac consisting of two parallel cryogenic strings, supported by two independent CP utilizing CDS components such as distribution boxes, transfer lines, feed caps and endcaps. In this paper, we describe the overall layout of the cryogenic distribution system and the major thermodynamic factors which influence the CDS design including heat loads, pressure drops, temperature profiles, and pressure relieving requirements. In addition the paper describes how the models are created to perform the analyses.« less

Development of an Exploration-Class Cascade Distillation System: Flight Like Prototype Preliminary Design

NASA Technical Reports Server (NTRS)

Callahan, Michael R.; Sargusingh, Miriam J.

2015-01-01

The ability to recover and purify water through physiochemical processes is crucial for realizing long-term human space missions, including both planetary habitation and space travel. Because of their robust nature, distillation systems have been actively pursued as one of the technologies for water recovery. One such technology is the Cascade Distillation System (CDS) a multi-stage vacuum rotary distiller system designed to recover water in a microgravity environment. Its rotating cascading distiller operates similarly to the state of the art (SOA) vapor compressor distiller (VCD), but its control scheme and ancillary components are judged to be straightforward and simpler to implement into a successful design. Through the Advanced Exploration Systems (AES) Life Support Systems (LSS) Project, the NASA Johnson Space Center (JSC) in collaboration with Honeywell International is developing a second generation flight forward prototype (CDS 2.0). The key objectives for the CDS 2.0 design task is to provide a flight forward ground prototype that demonstrates improvements over the SOA system in the areas of increased reliability and robustness, and reduced mass, power and volume. It will also incorporate exploration-class automation. The products of this task are a preliminary flight system design and a high fidelity prototype of an exploration class CDS. These products will inform the design and development of the third generation CDS which is targeted for on-orbit DTO. This paper details the preliminary design of the CDS 2.0.

Behavioral medicine perspectives on the design of health information technology to improve decision-making, guideline adherence, and care coordination in chronic pain management.

PubMed

Midboe, Amanda M; Lewis, Eleanor T; Cronkite, Ruth C; Chambers, Dallas; Goldstein, Mary K; Kerns, Robert D; Trafton, Jodie A

2011-03-01

Development of clinical decision support systems (CDSs) has tended to focus on facilitating medication management. An understanding of behavioral medicine perspectives on the usefulness of a CDS for patient care can expand CDSs to improve management of chronic disease. The purpose of this study is to explore feedback from behavioral medicine providers regarding the potential for CDSs to improve decision-making, care coordination, and guideline adherence in pain management. Qualitative methods were used to analyze semi-structured interview responses from behavioral medicine stakeholders following demonstration of an existing CDS for opioid prescribing, ATHENA-OT. Participants suggested that a CDS could assist with decision-making by educating providers, providing recommendations about behavioral therapy, facilitating risk assessment, and improving referral decisions. They suggested that a CDS could improve care coordination by facilitating division of workload, improving patient education, and increasing consideration and knowledge of options in other disciplines. Clinical decision support systems are promising tools for improving behavioral medicine care for chronic pain.

Clinical Decision Support for a Multicenter Trial of Pediatric Head Trauma

PubMed Central

Swietlik, Marguerite; Deakyne, Sara; Hoffman, Jeffrey M.; Grundmeier, Robert W.; Paterno, Marilyn D.; Rocha, Beatriz H.; Schaeffer, Molly H; Pabbathi, Deepika; Alessandrini, Evaline; Ballard, Dustin; Goldberg, Howard S.; Kuppermann, Nathan; Dayan, Peter S.

2016-01-01

Summary Introduction For children who present to emergency departments (EDs) due to blunt head trauma, ED clinicians must decide who requires computed tomography (CT) scanning to evaluate for traumatic brain injury (TBI). The Pediatric Emergency Care Applied Research Network (PECARN) derived and validated two age-based prediction rules to identify children at very low risk of clinically-important traumatic brain injuries (ciTBIs) who do not typically require CT scans. In this case report, we describe the strategy used to implement the PECARN TBI prediction rules via electronic health record (EHR) clinical decision support (CDS) as the intervention in a multicenter clinical trial. Methods Thirteen EDs participated in this trial. The 10 sites receiving the CDS intervention used the Epic® EHR. All sites implementing EHR-based CDS built the rules by using the vendor’s CDS engine. Based on a sociotechnical analysis, we designed the CDS so that recommendations could be displayed immediately after any provider entered prediction rule data. One central site developed and tested the intervention package to be exported to other sites. The intervention package included a clinical trial alert, an electronic data collection form, the CDS rules and the format for recommendations. Results The original PECARN head trauma prediction rules were derived from physician documentation while this pragmatic trial led each site to customize their workflows and allow multiple different providers to complete the head trauma assessments. These differences in workflows led to varying completion rates across sites as well as differences in the types of providers completing the electronic data form. Site variation in internal change management processes made it challenging to maintain the same rigor across all sites. This led to downstream effects when data reports were developed. Conclusions The process of a centralized build and export of a CDS system in one commercial EHR system successfully supported a multicenter clinical trial. PMID:27437059

Cascade Distillation Subsystem Development: Early Results from the Exploration Life Support Distillation Technology Comparison Test

NASA Technical Reports Server (NTRS)

Callahan, Michael R.; Patel, Vipul; Pickering, Karen D.

2010-01-01

In 2009, the Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell International, Torrance, California) was assessed in the National Aeronautics and Space Administration (NASA) Exploration Life Support (ELS) distillation comparison test. The purpose of the test was to collect data to support down-selection and development of a primary distillation technology for application in a lunar outpost water recovery system. The CDS portion of the comparison test was conducted between May 6 and August 19, 2009. The system was challenged with two pretreated test solutions, each intended to represent a feasible wastewater generated in a surface habitat. The 30-day equivalent wastewater loading volume for a crew of four was intended to be processed for each wastewater solution. Test Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. Test Solution 2 contained the addition of human-generated hygiene wastewater to the solution 1 waste stream components. Approximately 1500 kg of total wastewater was processed through the CDS during testing. Respective recoveries per solution were 93.4 +/- 0.7 and 90.3 +/- 0.5 percent. The average specific energy of the system during testing was calculated to be less than 120 W-hr/kg. The following paper provides detailed information and data on the performance of the CDS as challenged per the ELS distillation comparison test.

Creating Shareable Clinical Decision Support Rules for a Pharmacogenomics Clinical Guideline Using Structured Knowledge Representation.

PubMed

Linan, Margaret K; Sottara, Davide; Freimuth, Robert R

2015-01-01

Pharmacogenomics (PGx) guidelines contain drug-gene relationships, therapeutic and clinical recommendations from which clinical decision support (CDS) rules can be extracted, rendered and then delivered through clinical decision support systems (CDSS) to provide clinicians with just-in-time information at the point of care. Several tools exist that can be used to generate CDS rules that are based on computer interpretable guidelines (CIG), but none have been previously applied to the PGx domain. We utilized the Unified Modeling Language (UML), the Health Level 7 virtual medical record (HL7 vMR) model, and standard terminologies to represent the semantics and decision logic derived from a PGx guideline, which were then mapped to the Health eDecisions (HeD) schema. The modeling and extraction processes developed here demonstrate how structured knowledge representations can be used to support the creation of shareable CDS rules from PGx guidelines.

Evaluation of prescriber responses to pharmacogenomics clinical decision support for thiopurine S-methyltransferase testing.

PubMed

Ubanyionwu, Samuel; Formea, Christine M; Anderson, Benjamin; Wix, Kelly; Dierkhising, Ross; Caraballo, Pedro J

2018-02-15

Results of a study of prescribers' responses to a pharmacogenomics-based clinical decision support (CDS) alert designed to prompt thiopurine S -methyltransferase (TPMT) status testing are reported. A single-center, retrospective, chart review-based study was conducted to evaluate prescriber compliance with a pretest CDS alert that warned of potential thiopurine drug toxicity resulting from deficient TPMT activity due to TPMT gene polymorphism. The CDS alert was triggered when prescribers ordered thiopurine drugs for patients whose records did not indicate TPMT status or when historical thiopurine use was documented in the electronic health record. The alert pop-up also provided a link to online educational resources to guide thiopurine dosing calculations. During the 9-month study period, 500 CDS alerts were generated: in 101 cases (20%), TPMT phenotyping or TPMT genotyping was ordered; in 399 cases (80%), testing was not ordered. Multivariable regression analysis indicated that documentation of historical thiopurine use was the only independent predictor of test ordering. Among the 99 patients tested subsequent to CDS alerts, 70 (71%) had normal TPMT activity, 29 (29%) had intermediate activity, and none had deficient activity. The online resources provided thiopurine dosing recommendations applicable to 24 patients, but only 3 were prescribed guideline-supported doses after CDS alerts. The pretest CDS rule resulted in a large proportion of neglected alerts due to poor alerting accuracy and consequent alert fatigue. Prescriber usage of online thiopurine dosing resources was low. Copyright © 2018 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Development of a Tailored Intervention With Computerized Clinical Decision Support to Improve Quality of Care for Patients With Knee Osteoarthritis: Multi-Method Study.

PubMed

Van de Velde, Stijn; Kortteisto, Tiina; Spitaels, David; Jamtvedt, Gro; Roshanov, Pavel; Kunnamo, Ilkka; Aertgeerts, Bert; Vandvik, Per Olav; Flottorp, Signe

2018-06-11

Clinical practice patterns greatly diverge from evidence-based recommendations to manage knee osteoarthritis conservatively before resorting to surgery. This study aimed to tailor a guideline-based computerized decision support (CDS) intervention that facilitates the conservative management of knee osteoarthritis. Experts with backgrounds in clinical medicine, research, implementation, or health informatics suggested the most important recommendations for implementation, how to develop an implementation strategy, and how to form the CDS algorithms. In 6 focus group sessions, 8 general practitioners and 22 patients from Norway, Belgium, and Finland discussed the suggested CDS intervention and identified factors that would be most critical for the success of the intervention. The focus group moderators used the GUideline Implementation with DEcision Support checklist, which we developed to support consideration of CDS success factors. The experts prioritized 9 out of 22 recommendations for implementation. We formed the concept for 6 CDS algorithms to support implementation of these recommendations. The focus group suggested 59 unique factors that could affect the success of the presented CDS intervention. Five factors (out of the 59) were prioritized by focus group participants in every country, including the perceived potential to address the information needs of both patients and general practitioners; the credibility of CDS information; the timing of CDS for patients; and the need for personal dialogue about CDS between the general practitioner and the patient. The focus group participants supported the CDS intervention as a tool to improve the quality of care for patients with knee osteoarthritis through shared, evidence-based decision making. We aim to develop and implement the CDS based on these study results. Future research should address optimal ways to (1) provide patient-directed CDS, (2) enable more patient-specific CDS within the context of patient complexity, and (3) maintain user engagement with CDS over time. ©Stijn Van de Velde, Tiina Kortteisto, David Spitaels, Gro Jamtvedt, Pavel Roshanov, Ilkka Kunnamo, Bert Aertgeerts, Per Olav Vandvik, Signe Flottorp. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 11.06.2018.

Clinical Decision Support-based Quality Measurement (CDS-QM) Framework: Prototype Implementation, Evaluation, and Future Directions

PubMed Central

Kukhareva, Polina V; Kawamoto, Kensaku; Shields, David E; Barfuss, Darryl T; Halley, Anne M; Tippetts, Tyler J; Warner, Phillip B; Bray, Bruce E; Staes, Catherine J

2014-01-01

Electronic quality measurement (QM) and clinical decision support (CDS) are closely related but are typically implemented independently, resulting in significant duplication of effort. While it seems intuitive that technical approaches could be re-used across these two related use cases, such reuse is seldom reported in the literature, especially for standards-based approaches. Therefore, we evaluated the feasibility of using a standards-based CDS framework aligned with anticipated EHR certification criteria to implement electronic QM. The CDS-QM framework was used to automate a complex national quality measure (SCIP-VTE-2) at an academic healthcare system which had previously relied on time-consuming manual chart abstractions. Compared with 305 manually-reviewed reference cases, the recall of automated measurement was 100%. The precision was 96.3% (CI:92.6%-98.5%) for ascertaining the denominator and 96.2% (CI:92.3%-98.4%) for the numerator. We therefore validated that a standards-based CDS-QM framework can successfully enable automated QM, and we identified benefits and challenges with this approach. PMID:25954389

Comparison of Overridden Medication-related Clinical Decision Support in the Intensive Care Unit between a Commercial System and a Legacy System.

PubMed

Wong, Adrian; Wright, Adam; Seger, Diane L; Amato, Mary G; Fiskio, Julie M; Bates, David

2017-08-23

Electronic health records (EHRs) with clinical decision support (CDS) have shown to be effective at improving patient safety. Despite this, alerts delivered as part of CDS are overridden frequently, which is of concern in the critical care population as this group may have an increased risk of harm. Our organization recently transitioned from an internally-developed EHR to a commercial system. Data comparing various EHR systems, especially after transitions between EHRs, are needed to identify areas for improvement. To compare the two systems and identify areas for potential improvement with the new commercial system at a single institution. Overridden medication-related CDS alerts were included from October to December of the systems' respective years (legacy, 2011; commercial, 2015), restricted to three intensive care units. The two systems were compared with regards to CDS presentation and override rates for four types of CDS: drug-allergy, drug-drug interaction (DDI), geriatric and renal alerts. A post hoc analysis to evaluate for adverse drug events (ADEs) potentially resulting from overridden alerts was performed for 'contraindicated' DDIs via chart review. There was a significant increase in provider exposure to alerts and alert overrides in the commercial system (commercial: n=5,535; legacy: n=1,030). Rates of overrides were higher for the allergy and DDI alerts (p<0.001) in the commercial system. Geriatric and renal alerts were significantly different in incidence and presentation between the two systems. No ADEs were identified in an analysis of 43 overridden contraindicated DDI alerts. The vendor system had much higher rates of both alerts and overrides, although we did not find evidence of harm in a review of DDIs which were overridden. We propose recommendations for improving our current system which may be helpful to other similar institutions; improving both alert presentation and the underlying knowledge base appear important.

Usability evaluation of pharmacogenomics clinical decision support aids and clinical knowledge resources in a computerized provider order entry system: a mixed methods approach.

PubMed

Devine, Emily Beth; Lee, Chia-Ju; Overby, Casey L; Abernethy, Neil; McCune, Jeannine; Smith, Joe W; Tarczy-Hornoch, Peter

2014-07-01

Pharmacogenomics (PGx) is positioned to have a widespread impact on the practice of medicine, yet physician acceptance is low. The presentation of context-specific PGx information, in the form of clinical decision support (CDS) alerts embedded in a computerized provider order entry (CPOE) system, can aid uptake. Usability evaluations can inform optimal design, which, in turn, can spur adoption. The study objectives were to: (1) evaluate an early prototype, commercial CPOE system with PGx-CDS alerts in a simulated environment, (2) identify potential improvements to the system user interface, and (3) understand the contexts under which PGx knowledge embedded in an electronic health record is useful to prescribers. Using a mixed methods approach, we presented seven cardiologists and three oncologists with five hypothetical clinical case scenarios. Each scenario featured a drug for which a gene encoding drug metabolizing enzyme required consideration of dosage adjustment. We used Morae(®) to capture comments and on-screen movements as participants prescribed each drug. In addition to PGx-CDS alerts, 'Infobutton(®)' and 'Evidence' icons provided participants with clinical knowledge resources to aid decision-making. Nine themes emerged. Five suggested minor improvements to the CPOE user interface; two suggested presenting PGx information through PGx-CDS alerts using an 'Infobutton' or 'Evidence' icon. The remaining themes were strong recommendations to provide succinct, relevant guidelines and dosing recommendations of phenotypic information from credible and trustworthy sources; any more information was overwhelming. Participants' median rating of PGx-CDS system usability was 2 on a Likert scale ranging from 1 (strongly agree) to 7 (strongly disagree). Usability evaluation results suggest that participants considered PGx information important for improving prescribing decisions; and that they would incorporate PGx-CDS when information is presented in relevant and useful ways. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Reducing Diagnostic Error with Computer-Based Clinical Decision Support

ERIC Educational Resources Information Center

Greenes, Robert A.

2009-01-01

Information technology approaches to delivering diagnostic clinical decision support (CDS) are the subject of the papers to follow in the proceedings. These will address the history of CDS and present day approaches (Miller), evaluation of diagnostic CDS methods (Friedman), and the role of clinical documentation in supporting diagnostic decision…

Qualitative analysis of vendor discussions on the procurement of Computerised Physician Order Entry and Clinical Decision Support systems in hospitals

PubMed Central

Cresswell, Kathrin M; Lee, Lisa; Slee, Ann; Coleman, Jamie; Bates, David W; Sheikh, Aziz

2015-01-01

Objectives We studied vendor perspectives about potentially transferable lessons for implementing organisations and national strategies surrounding the procurement of Computerised Physician Order Entry (CPOE)/Clinical Decision Support (CDS) systems in English hospitals. Setting Data were collected from digitally audio-recorded discussions from a series of CPOE/CDS vendor round-table discussions held in September 2014 in the UK. Participants Nine participants, representing 6 key vendors operating in the UK, attended. The discussions were transcribed verbatim and thematically analysed. Results Vendors reported a range of challenges surrounding the procurement and contracting processes of CPOE/CDS systems, including hospitals’ inability to adequately assess their own needs and then select a suitable product, rushed procurement and implementation processes that resulted in difficulties in meaningfully engaging with vendors, as well as challenges relating to contracting leading to ambiguities in implementation roles. Consequently, relationships between system vendors and hospitals were often strained, the vendors attributing this to a lack of hospital management's appreciation of the complexities associated with implementation efforts. Future anticipated challenges included issues surrounding the standardisation of data to enable their aggregation across systems for effective secondary uses, and implementation of data exchange with providers outside the hospital. Conclusions Our results indicate that there are significant issues surrounding capacity to procure and optimise CPOE/CDS systems among UK hospitals. There is an urgent need to encourage more synergistic and collaborative working between providers and vendors and for a more centralised support for National Health Service hospitals, which draws on a wider body of experience, including a formalised procurement framework with value-based product specifications. PMID:26503385

Integrative review of clinical decision support for registered nurses in acute care settings.

PubMed

Dunn Lopez, Karen; Gephart, Sheila M; Raszewski, Rebecca; Sousa, Vanessa; Shehorn, Lauren E; Abraham, Joanna

2017-03-01

To report on the state of the science of clinical decision support (CDS) for hospital bedside nurses. We performed an integrative review of qualitative and quantitative peer-reviewed original research studies using a structured search of PubMed, Embase, Cumulative Index to Nursing and Applied Health Literature (CINAHL), Scopus, Web of Science, and IEEE Xplore (Institute of Electrical and Electronics Engineers Xplore Digital Library). We included articles that reported on CDS targeting bedside nurses and excluded in stages based on rules for titles, abstracts, and full articles. We extracted research design and methods, CDS purpose, electronic health record integration, usability, and process and patient outcomes. Our search yielded 3157 articles. After removing duplicates and applying exclusion rules, 28 articles met the inclusion criteria. The majority of studies were single-site, descriptive or qualitative (43%) or quasi-experimental (36%). There was only 1 randomized controlled trial. The purpose of most CDS was to support diagnostic decision-making (36%), guideline adherence (32%), medication management (29%), and situational awareness (25%). All the studies that included process outcomes (7) and usability outcomes (4) and also had analytic procedures to detect changes in outcomes demonstrated statistically significant improvements. Three of 4 studies that included patient outcomes and also had analytic procedures to detect change showed statistically significant improvements. No negative effects of CDS were found on process, usability, or patient outcomes. Clinical support systems targeting bedside nurses have positive effects on outcomes and hold promise for improving care quality; however, this research is lagging behind studies of CDS targeting medical decision-making in both volume and level of evidence. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Design, Development, and Initial Evaluation of a Terminology for Clinical Decision Support and Electronic Clinical Quality Measurement.

PubMed

Lin, Yanhua; Staes, Catherine J; Shields, David E; Kandula, Vijay; Welch, Brandon M; Kawamoto, Kensaku

2015-01-01

When coupled with a common information model, a common terminology for clinical decision support (CDS) and electronic clinical quality measurement (eCQM) could greatly facilitate the distributed development and sharing of CDS and eCQM knowledge resources. To enable such scalable knowledge authoring and sharing, we systematically developed an extensible and standards-based terminology for CDS and eCQM in the context of the HL7 Virtual Medical Record (vMR) information model. The development of this terminology entailed three steps: (1) systematic, physician-curated concept identification from sources such as the Health Information Technology Standards Panel (HITSP) and the SNOMED-CT CORE problem list; (2) concept de-duplication leveraging the Unified Medical Language System (UMLS) MetaMap and Metathesaurus; and (3) systematic concept naming using standard terminologies and heuristic algorithms. This process generated 3,046 concepts spanning 68 domains. Evaluation against representative CDS and eCQM resources revealed approximately 50-70% concept coverage, indicating the need for continued expansion of the terminology.

Design, Development, and Initial Evaluation of a Terminology for Clinical Decision Support and Electronic Clinical Quality Measurement

PubMed Central

Lin, Yanhua; Staes, Catherine J; Shields, David E; Kandula, Vijay; Welch, Brandon M; Kawamoto, Kensaku

2015-01-01

When coupled with a common information model, a common terminology for clinical decision support (CDS) and electronic clinical quality measurement (eCQM) could greatly facilitate the distributed development and sharing of CDS and eCQM knowledge resources. To enable such scalable knowledge authoring and sharing, we systematically developed an extensible and standards-based terminology for CDS and eCQM in the context of the HL7 Virtual Medical Record (vMR) information model. The development of this terminology entailed three steps: (1) systematic, physician-curated concept identification from sources such as the Health Information Technology Standards Panel (HITSP) and the SNOMED-CT CORE problem list; (2) concept de-duplication leveraging the Unified Medical Language System (UMLS) MetaMap and Metathesaurus; and (3) systematic concept naming using standard terminologies and heuristic algorithms. This process generated 3,046 concepts spanning 68 domains. Evaluation against representative CDS and eCQM resources revealed approximately 50–70% concept coverage, indicating the need for continued expansion of the terminology. PMID:26958220

Using statistical anomaly detection models to find clinical decision support malfunctions.

PubMed

Ray, Soumi; McEvoy, Dustin S; Aaron, Skye; Hickman, Thu-Trang; Wright, Adam

2018-05-11

Malfunctions in Clinical Decision Support (CDS) systems occur due to a multitude of reasons, and often go unnoticed, leading to potentially poor outcomes. Our goal was to identify malfunctions within CDS systems. We evaluated 6 anomaly detection models: (1) Poisson Changepoint Model, (2) Autoregressive Integrated Moving Average (ARIMA) Model, (3) Hierarchical Divisive Changepoint (HDC) Model, (4) Bayesian Changepoint Model, (5) Seasonal Hybrid Extreme Studentized Deviate (SHESD) Model, and (6) E-Divisive with Median (EDM) Model and characterized their ability to find known anomalies. We analyzed 4 CDS alerts with known malfunctions from the Longitudinal Medical Record (LMR) and Epic® (Epic Systems Corporation, Madison, WI, USA) at Brigham and Women's Hospital, Boston, MA. The 4 rules recommend lead testing in children, aspirin therapy in patients with coronary artery disease, pneumococcal vaccination in immunocompromised adults and thyroid testing in patients taking amiodarone. Poisson changepoint, ARIMA, HDC, Bayesian changepoint and the SHESD model were able to detect anomalies in an alert for lead screening in children and in an alert for pneumococcal conjugate vaccine in immunocompromised adults. EDM was able to detect anomalies in an alert for monitoring thyroid function in patients on amiodarone. Malfunctions/anomalies occur frequently in CDS alert systems. It is important to be able to detect such anomalies promptly. Anomaly detection models are useful tools to aid such detections.

Photodegradation of rhodamine B over biomass-derived activated carbon supported CdS nanomaterials under visible irradiation

NASA Astrophysics Data System (ADS)

Huang, Hai-Bo; Wang, Yu; Cai, Feng-Ying; Jiao, Wen-Bin; Zhang, Ning; Liu, Cheng; Cao, Hai-Lei; Lü, Jian

2017-12-01

A family of new CdS@SAC composite materials was successfully prepared through the deposition of as-synthesized CdS nanomaterials on various lotus-seedpod-derived activated carbon (SAC) materials. The SAC supports derived at different activation temperatures exhibited considerably large surface areas and various microstructures that were responsible for the enhanced photocatalytic performance of CdS@SAC composite materials towards the photodegradation of rhodamine B (RhB) under visible irradiation. The best-performing CdS@SAC-800 showed excellent photocatalytic activity with a rate constant of ca. 2.40×10–2 min–1, which was approximately 13 times higher than that of the CdS precursor. Moreover, the estimated band gap energy of CdS@SAC-800 (1.99 eV) was significantly lower than that of the CdS precursor (2.22 eV), which suggested considerable strength of interface contact between the CdS and carbon support, as well as efficient light harvesting capacity of the composite material. Further photocatalytic study indicated that the SAC supports enhanced synergistically the accessibility of organic substrates, the efficiency of solar energy harvesting, as well as the separation of photogenerated electrons and holes in this system. Improved photocatalytic activity of the composite materials was largely due to the increased generation of active species such as h+, OH•, O2•‑ etc. This work provides a facile and low-cost pathway to fabricate composite photocatalysts for viable degradation of organic pollutants.

Implementation Pearls from a New Guidebook on Improving Medication Use and Outcomes with Clinical Decision Support

PubMed Central

Sirajuddin, Anwar M; Osheroff, Jerome A.; Sittig, Dean F.; Chuo, John; Velasco, Ferdinand; Collins, David A.

2012-01-01

Effective clinical decision support (CDS) is essential for addressing healthcare performance improvement imperatives, but care delivery organizations (CDO) typically struggle with CDS deployment. Ensuring safe and effective medication delivery to patients is a central focus of CDO performance improvement efforts, and this article provides an overview of best-practice strategies for applying CDS to these goals. The strategies discussed are drawn from a new guidebook, co-published and co-sponsored by more than a dozen leading organizations. Developed by scores of CDS implementers and experts, the guidebook outlines key steps and success factors for applying CDS to medication management. A central thesis is that improving outcomes with CDS interventions requires that the CDS five rights be addressed successfully. That is, the interventions must deliver the right information, to the right person, in the right format, through the right channel, at the right point in workflow. This paper provides further details about these CDS five rights, and highlights other important strategies for successful CDS programs. PMID:19894486

The Morningside Initiative: Collaborative Development of a Knowledge Repository to Accelerate Adoption of Clinical Decision Support

PubMed Central

Greenes, Robert; Bloomrosen, Meryl; Brown-Connolly, Nancy E.; Curtis, Clayton; Detmer, Don E; Enberg, Robert; Fridsma, Douglas; Fry, Emory; Goldstein, Mary K; Haug, Peter; Hulse, Nathan; Hongsermeier, Tonya; Maviglia, Saverio; Robbins, Craig W; Shah, Hemant

2010-01-01

The Morningside Initiative is a public-private activity that has evolved from an August, 2007, meeting at the Morningside Inn, in Frederick, MD, sponsored by the Telemedicine and Advanced Technology Research Center (TATRC) of the US Army Medical Research Materiel Command. Participants were subject matter experts in clinical decision support (CDS) and included representatives from the Department of Defense, Veterans Health Administration, Kaiser Permanente, Partners Healthcare System, Henry Ford Health System, Arizona State University, and the American Medical Informatics Association (AMIA). The Morningside Initiative was convened in response to the AMIA Roadmap for National Action on Clinical Decision Support and on the basis of other considerations and experiences of the participants. Its formation was the unanimous recommendation of participants at the 2007 meeting which called for creating a shared repository of executable knowledge for diverse health care organizations and practices, as well as health care system vendors. The rationale is based on the recognition that sharing of clinical knowledge needed for CDS across organizations is currently virtually non-existent, and that, given the considerable investment needed for creating, maintaining and updating authoritative knowledge, which only larger organizations have been able to undertake, this is an impediment to widespread adoption and use of CDS. The Morningside Initiative intends to develop and refine (1) an organizational framework, (2) a technical approach, and (3) CDS content acquisition and management processes for sharing CDS knowledge content, tools, and experience that will scale with growing numbers of participants and can be expanded in scope of content and capabilities. Intermountain Healthcare joined the initial set of participants shortly after its formation. The efforts of the Morningside Initiative are intended to serve as the basis for a series of next steps in a national agenda for CDS. It is based on the belief that sharing of knowledge can be highly effective as is the case in other competitive domains such as genomics. Participants in the Morningside Initiative believe that a coordinated effort between the private and public sectors is needed to accomplish this goal and that a small number of highly visible and respected health care organizations in the public and private sector can lead by example. Ultimately, a future collaborative knowledge sharing organization must have a sustainable long-term business model for financial support. PMID:21603282

The morningside initiative: collaborative development of a knowledge repository to accelerate adoption of clinical decision support.

PubMed

Greenes, Robert; Bloomrosen, Meryl; Brown-Connolly, Nancy E; Curtis, Clayton; Detmer, Don E; Enberg, Robert; Fridsma, Douglas; Fry, Emory; Goldstein, Mary K; Haug, Peter; Hulse, Nathan; Hongsermeier, Tonya; Maviglia, Saverio; Robbins, Craig W; Shah, Hemant

2010-01-01

The Morningside Initiative is a public-private activity that has evolved from an August, 2007, meeting at the Morningside Inn, in Frederick, MD, sponsored by the Telemedicine and Advanced Technology Research Center (TATRC) of the US Army Medical Research Materiel Command. Participants were subject matter experts in clinical decision support (CDS) and included representatives from the Department of Defense, Veterans Health Administration, Kaiser Permanente, Partners Healthcare System, Henry Ford Health System, Arizona State University, and the American Medical Informatics Association (AMIA). The Morningside Initiative was convened in response to the AMIA Roadmap for National Action on Clinical Decision Support and on the basis of other considerations and experiences of the participants. Its formation was the unanimous recommendation of participants at the 2007 meeting which called for creating a shared repository of executable knowledge for diverse health care organizations and practices, as well as health care system vendors. The rationale is based on the recognition that sharing of clinical knowledge needed for CDS across organizations is currently virtually non-existent, and that, given the considerable investment needed for creating, maintaining and updating authoritative knowledge, which only larger organizations have been able to undertake, this is an impediment to widespread adoption and use of CDS. The Morningside Initiative intends to develop and refine (1) an organizational framework, (2) a technical approach, and (3) CDS content acquisition and management processes for sharing CDS knowledge content, tools, and experience that will scale with growing numbers of participants and can be expanded in scope of content and capabilities. Intermountain Healthcare joined the initial set of participants shortly after its formation. The efforts of the Morningside Initiative are intended to serve as the basis for a series of next steps in a national agenda for CDS. It is based on the belief that sharing of knowledge can be highly effective as is the case in other competitive domains such as genomics. Participants in the Morningside Initiative believe that a coordinated effort between the private and public sectors is needed to accomplish this goal and that a small number of highly visible and respected health care organizations in the public and private sector can lead by example. Ultimately, a future collaborative knowledge sharing organization must have a sustainable long-term business model for financial support.

A Multidisciplinary Sepsis Program Enabled by a Two-Stage Clinical Decision Support System: Factors That Influence Patient Outcomes.

PubMed

Amland, Robert C; Haley, James M; Lyons, Jason J

2016-11-01

Sepsis is an inflammatory response triggered by infection, with risk of in-hospital mortality fueled by disease progression. Early recognition and intervention by multidisciplinary sepsis programs may reverse the inflammatory response among at-risk patient populations, potentially improving outcomes. This retrospective study of a sepsis program enabled by a 2-stage sepsis Clinical Decision Support (CDS) system sought to evaluate the program's impact, identify early indicators that may influence outcomes, and uncover opportunities for quality improvement. Data encompassed 16 527 adult hospitalizations from 2014 and 2015. Of 2108 non-intensive care unit patients screened-in by sepsis CDS, 97% patients were stratified by 177 providers. Risk of adverse outcome improved 30% from baseline to year end, with gains materializing and stabilizing at month 7 after sepsis program go-live. Early indicators likely to influence outcomes include patient age, recent hospitalization, electrolyte abnormalities, hypovolemic shock, hypoxemia, patient location when sepsis CDS activated, and specific alert patterns. © The Author(s) 2015.

Clinical Decision Support: a 25 Year Retrospective and a 25 Year Vision.

PubMed

Middleton, B; Sittig, D F; Wright, A

2016-08-02

The objective of this review is to summarize the state of the art of clinical decision support (CDS) circa 1990, review progress in the 25 year interval from that time, and provide a vision of what CDS might look like 25 years hence, or circa 2040. Informal review of the medical literature with iterative review and discussion among the authors to arrive at six axes (data, knowledge, inference, architecture and technology, implementation and integration, and users) to frame the review and discussion of selected barriers and facilitators to the effective use of CDS. In each of the six axes, significant progress has been made. Key advances in structuring and encoding standardized data with an increased availability of data, development of knowledge bases for CDS, and improvement of capabilities to share knowledge artifacts, explosion of methods analyzing and inferring from clinical data, evolution of information technologies and architectures to facilitate the broad application of CDS, improvement of methods to implement CDS and integrate CDS into the clinical workflow, and increasing sophistication of the end-user, all have played a role in improving the effective use of CDS in healthcare delivery. CDS has evolved dramatically over the past 25 years and will likely evolve just as dramatically or more so over the next 25 years. Increasingly, the clinical encounter between a clinician and a patient will be supported by a wide variety of cognitive aides to support diagnosis, treatment, care-coordination, surveillance and prevention, and health maintenance or wellness.

Agile Acceptance Test–Driven Development of Clinical Decision Support Advisories: Feasibility of Using Open Source Software

PubMed Central

Baldwin, Krystal L; Kannan, Vaishnavi; Flahaven, Emily L; Parks, Cassandra J; Ott, Jason M; Willett, Duwayne L

2018-01-01

Background Moving to electronic health records (EHRs) confers substantial benefits but risks unintended consequences. Modern EHRs consist of complex software code with extensive local configurability options, which can introduce defects. Defects in clinical decision support (CDS) tools are surprisingly common. Feasible approaches to prevent and detect defects in EHR configuration, including CDS tools, are needed. In complex software systems, use of test–driven development and automated regression testing promotes reliability. Test–driven development encourages modular, testable design and expanding regression test coverage. Automated regression test suites improve software quality, providing a “safety net” for future software modifications. Each automated acceptance test serves multiple purposes, as requirements (prior to build), acceptance testing (on completion of build), regression testing (once live), and “living” design documentation. Rapid-cycle development or “agile” methods are being successfully applied to CDS development. The agile practice of automated test–driven development is not widely adopted, perhaps because most EHR software code is vendor-developed. However, key CDS advisory configuration design decisions and rules stored in the EHR may prove amenable to automated testing as “executable requirements.” Objective We aimed to establish feasibility of acceptance test–driven development of clinical decision support advisories in a commonly used EHR, using an open source automated acceptance testing framework (FitNesse). Methods Acceptance tests were initially constructed as spreadsheet tables to facilitate clinical review. Each table specified one aspect of the CDS advisory’s expected behavior. Table contents were then imported into a test suite in FitNesse, which queried the EHR database to automate testing. Tests and corresponding CDS configuration were migrated together from the development environment to production, with tests becoming part of the production regression test suite. Results We used test–driven development to construct a new CDS tool advising Emergency Department nurses to perform a swallowing assessment prior to administering oral medication to a patient with suspected stroke. Test tables specified desired behavior for (1) applicable clinical settings, (2) triggering action, (3) rule logic, (4) user interface, and (5) system actions in response to user input. Automated test suite results for the “executable requirements” are shown prior to building the CDS alert, during build, and after successful build. Conclusions Automated acceptance test–driven development and continuous regression testing of CDS configuration in a commercial EHR proves feasible with open source software. Automated test–driven development offers one potential contribution to achieving high-reliability EHR configuration. Vetting acceptance tests with clinicians elicits their input on crucial configuration details early during initial CDS design and iteratively during rapid-cycle optimization. PMID:29653922

Agile Acceptance Test-Driven Development of Clinical Decision Support Advisories: Feasibility of Using Open Source Software.

PubMed

Basit, Mujeeb A; Baldwin, Krystal L; Kannan, Vaishnavi; Flahaven, Emily L; Parks, Cassandra J; Ott, Jason M; Willett, Duwayne L

2018-04-13

Moving to electronic health records (EHRs) confers substantial benefits but risks unintended consequences. Modern EHRs consist of complex software code with extensive local configurability options, which can introduce defects. Defects in clinical decision support (CDS) tools are surprisingly common. Feasible approaches to prevent and detect defects in EHR configuration, including CDS tools, are needed. In complex software systems, use of test-driven development and automated regression testing promotes reliability. Test-driven development encourages modular, testable design and expanding regression test coverage. Automated regression test suites improve software quality, providing a "safety net" for future software modifications. Each automated acceptance test serves multiple purposes, as requirements (prior to build), acceptance testing (on completion of build), regression testing (once live), and "living" design documentation. Rapid-cycle development or "agile" methods are being successfully applied to CDS development. The agile practice of automated test-driven development is not widely adopted, perhaps because most EHR software code is vendor-developed. However, key CDS advisory configuration design decisions and rules stored in the EHR may prove amenable to automated testing as "executable requirements." We aimed to establish feasibility of acceptance test-driven development of clinical decision support advisories in a commonly used EHR, using an open source automated acceptance testing framework (FitNesse). Acceptance tests were initially constructed as spreadsheet tables to facilitate clinical review. Each table specified one aspect of the CDS advisory's expected behavior. Table contents were then imported into a test suite in FitNesse, which queried the EHR database to automate testing. Tests and corresponding CDS configuration were migrated together from the development environment to production, with tests becoming part of the production regression test suite. We used test-driven development to construct a new CDS tool advising Emergency Department nurses to perform a swallowing assessment prior to administering oral medication to a patient with suspected stroke. Test tables specified desired behavior for (1) applicable clinical settings, (2) triggering action, (3) rule logic, (4) user interface, and (5) system actions in response to user input. Automated test suite results for the "executable requirements" are shown prior to building the CDS alert, during build, and after successful build. Automated acceptance test-driven development and continuous regression testing of CDS configuration in a commercial EHR proves feasible with open source software. Automated test-driven development offers one potential contribution to achieving high-reliability EHR configuration. Vetting acceptance tests with clinicians elicits their input on crucial configuration details early during initial CDS design and iteratively during rapid-cycle optimization. ©Mujeeb A Basit, Krystal L Baldwin, Vaishnavi Kannan, Emily L Flahaven, Cassandra J Parks, Jason M Ott, Duwayne L Willett. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 13.04.2018.

NASA Cloud-Based Climate Data Services

NASA Astrophysics Data System (ADS)

McInerney, M. A.; Schnase, J. L.; Duffy, D. Q.; Tamkin, G. S.; Strong, S.; Ripley, W. D., III; Thompson, J. H.; Gill, R.; Jasen, J. E.; Samowich, B.; Pobre, Z.; Salmon, E. M.; Rumney, G.; Schardt, T. D.

2012-12-01

Cloud-based scientific data services are becoming an important part of NASA's mission. Our technological response is built around the concept of specialized virtual climate data servers, repetitive cloud provisioning, image-based deployment and distribution, and virtualization-as-a-service (VaaS). A virtual climate data server (vCDS) is an Open Archive Information System (OAIS) compliant, iRODS-based data server designed to support a particular type of scientific data collection. iRODS is data grid middleware that provides policy-based control over collection-building, managing, querying, accessing, and preserving large scientific data sets. We have deployed vCDS Version 1.0 in the Amazon EC2 cloud using S3 object storage and are using the system to deliver a subset of NASA's Intergovernmental Panel on Climate Change (IPCC) data products to the latest CentOS federated version of Earth System Grid Federation (ESGF), which is also running in the Amazon cloud. vCDS-managed objects are exposed to ESGF through FUSE (Filesystem in User Space), which presents a POSIX-compliant filesystem abstraction to applications such as the ESGF server that require such an interface. A vCDS manages data as a distinguished collection for a person, project, lab, or other logical unit. A vCDS can manage a collection across multiple storage resources using rules and microservices to enforce collection policies. And a vCDS can federate with other vCDSs to manage multiple collections over multiple resources, thereby creating what can be thought of as an ecosystem of managed collections. With the vCDS approach, we are trying to enable the full information lifecycle management of scientific data collections and make tractable the task of providing diverse climate data services. In this presentation, we describe our approach, experiences, lessons learned, and plans for the future.; (A) vCDS/ESG system stack. (B) Conceptual architecture for NASA cloud-based data services.

Recommended practices for computerized clinical decision support and knowledge management in community settings: a qualitative study

PubMed Central

2012-01-01

Background The purpose of this study was to identify recommended practices for computerized clinical decision support (CDS) development and implementation and for knowledge management (KM) processes in ambulatory clinics and community hospitals using commercial or locally developed systems in the U.S. Methods Guided by the Multiple Perspectives Framework, the authors conducted ethnographic field studies at two community hospitals and five ambulatory clinic organizations across the U.S. Using a Rapid Assessment Process, a multidisciplinary research team: gathered preliminary assessment data; conducted on-site interviews, observations, and field surveys; analyzed data using both template and grounded methods; and developed universal themes. A panel of experts produced recommended practices. Results The team identified ten themes related to CDS and KM. These include: 1) workflow; 2) knowledge management; 3) data as a foundation for CDS; 4) user computer interaction; 5) measurement and metrics; 6) governance; 7) translation for collaboration; 8) the meaning of CDS; 9) roles of special, essential people; and 10) communication, training, and support. Experts developed recommendations about each theme. The original Multiple Perspectives framework was modified to make explicit a new theoretical construct, that of Translational Interaction. Conclusions These ten themes represent areas that need attention if a clinic or community hospital plans to implement and successfully utilize CDS. In addition, they have implications for workforce education, research, and national-level policy development. The Translational Interaction construct could guide future applied informatics research endeavors. PMID:22333210

Structured representation for core elements of common clinical decision support interventions to facilitate knowledge sharing.

PubMed

Zhou, Li; Hongsermeier, Tonya; Boxwala, Aziz; Lewis, Janet; Kawamoto, Kensaku; Maviglia, Saverio; Gentile, Douglas; Teich, Jonathan M; Rocha, Roberto; Bell, Douglas; Middleton, Blackford

2013-01-01

At present, there are no widely accepted, standard approaches for representing computer-based clinical decision support (CDS) intervention types and their structural components. This study aimed to identify key requirements for the representation of five widely utilized CDS intervention types: alerts and reminders, order sets, infobuttons, documentation templates/forms, and relevant data presentation. An XML schema was proposed for representing these interventions and their core structural elements (e.g., general metadata, applicable clinical scenarios, CDS inputs, CDS outputs, and CDS logic) in a shareable manner. The schema was validated by building CDS artifacts for 22 different interventions, targeted toward guidelines and clinical conditions called for in the 2011 Meaningful Use criteria. Custom style sheets were developed to render the XML files in human-readable form. The CDS knowledge artifacts were shared via a public web portal. Our experience also identifies gaps in existing standards and informs future development of standards for CDS knowledge representation and sharing.

Clinical Decision Support: a 25 Year Retrospective and a 25 Year Vision

PubMed Central

Sittig, D. F.; Wright, A.

2016-01-01

Summary Objective The objective of this review is to summarize the state of the art of clinical decision support (CDS) circa 1990, review progress in the 25 year interval from that time, and provide a vision of what CDS might look like 25 years hence, or circa 2040. Method Informal review of the medical literature with iterative review and discussion among the authors to arrive at six axes (data, knowledge, inference, architecture and technology, implementation and integration, and users) to frame the review and discussion of selected barriers and facilitators to the effective use of CDS. Result In each of the six axes, significant progress has been made. Key advances in structuring and encoding standardized data with an increased availability of data, development of knowledge bases for CDS, and improvement of capabilities to share knowledge artifacts, explosion of methods analyzing and inferring from clinical data, evolution of information technologies and architectures to facilitate the broad application of CDS, improvement of methods to implement CDS and integrate CDS into the clinical workflow, and increasing sophistication of the end-user, all have played a role in improving the effective use of CDS in healthcare delivery. Conclusion CDS has evolved dramatically over the past 25 years and will likely evolve just as dramatically or more so over the next 25 years. Increasingly, the clinical encounter between a clinician and a patient will be supported by a wide variety of cognitive aides to support diagnosis, treatment, care-coordination, surveillance and prevention, and health maintenance or wellness. PMID:27488402

Use of Mobile Clinical Decision Support Software by Junior Doctors at a UK Teaching Hospital: Identification and Evaluation of Barriers to Engagement.

PubMed

Patel, Rakesh; Green, William; Shahzad, Muhammad Waseem; Larkin, Chris

2015-08-13

Clinical decision support (CDS) tools improve clinical diagnostic decision making and patient safety. The availability of CDS to health care professionals has grown in line with the increased prevalence of apps and smart mobile devices. Despite these benefits, patients may have safety concerns about the use of mobile devices around medical equipment. This research explored the engagement of junior doctors (JDs) with CDS and the perceptions of patients about their use. There were three objectives for this research: (1) to measure the actual usage of CDS tools on mobile devices (mCDS) by JDs, (2) to explore the perceptions of JDs about the drivers and barriers to using mCDS, and (3) to explore the perceptions of patients about the use of mCDS. This study used a mixed-methods approach to study the engagement of JDs with CDS accessed through mobile devices. Usage data were collected on the number of interactions by JDs with mCDS. The perceived drivers and barriers for JDs to using CDS were then explored by interviews. Finally, these findings were contrasted with the perception of patients about the use of mCDS by JDs. Nine of the 16 JDs made a total of 142 recorded interactions with the mCDS over a 4-month period. Only 27 of the 114 interactions (24%) that could be categorized as on-shift or off-shift occurred on-shift. Eight individual, institutional, and cultural barriers to engagement emerged from interviews with the user group. In contrast to reported cautions and concerns about the impact of clinicians' use of mobile phone on patient health and safety, patients had positive perceptions about the use of mCDS. Patients reported positive perceptions toward mCDS. The usage of mCDS to support clinical decision making was considered to be positive as part of everyday clinical practice. The degree of engagement was found to be limited due to a number of individual, institutional, and cultural barriers. The majority of mCDS engagement occurred outside of the workplace. Further research is required to verify these findings and assess their implications for future policy and practice.

Clinical Decision Support Alert Appropriateness: A Review and Proposal for Improvement

PubMed Central

McCoy, Allison B.; Thomas, Eric J.; Krousel-Wood, Marie; Sittig, Dean F.

2014-01-01

Background Many healthcare providers are adopting clinical decision support (CDS) systems to improve patient safety and meet meaningful use requirements. Computerized alerts that prompt clinicians about drug-allergy, drug-drug, and drug-disease warnings or provide dosing guidance are most commonly implemented. Alert overrides, which occur when clinicians do not follow the guidance presented by the alert, can hinder improved patient outcomes. Methods We present a review of CDS alerts and describe a proposal to develop novel methods for evaluating and improving CDS alerts that builds upon traditional informatics approaches. Our proposal incorporates previously described models for predicting alert overrides that utilize retrospective chart review to determine which alerts are clinically relevant and which overrides are justifiable. Results Despite increasing implementations of CDS alerts, detailed evaluations rarely occur because of the extensive labor involved in manual chart reviews to determine alert and response appropriateness. Further, most studies have solely evaluated alert overrides that are appropriate or justifiable. Our proposal expands the use of web-based monitoring tools with an interactive dashboard for evaluating CDS alert and response appropriateness that incorporates the predictive models. The dashboard provides 2 views, an alert detail view and a patient detail view, to provide a full history of alerts and help put the patient's events in context. Conclusion The proposed research introduces several innovations to address the challenges and gaps in alert evaluations. This research can transform alert evaluation processes across healthcare settings, leading to improved CDS, reduced alert fatigue, and increased patient safety. PMID:24940129

A proposed clinical decision support architecture capable of supporting whole genome sequence information.

PubMed

Welch, Brandon M; Loya, Salvador Rodriguez; Eilbeck, Karen; Kawamoto, Kensaku

2014-04-04

Whole genome sequence (WGS) information may soon be widely available to help clinicians personalize the care and treatment of patients. However, considerable barriers exist, which may hinder the effective utilization of WGS information in a routine clinical care setting. Clinical decision support (CDS) offers a potential solution to overcome such barriers and to facilitate the effective use of WGS information in the clinic. However, genomic information is complex and will require significant considerations when developing CDS capabilities. As such, this manuscript lays out a conceptual framework for a CDS architecture designed to deliver WGS-guided CDS within the clinical workflow. To handle the complexity and breadth of WGS information, the proposed CDS framework leverages service-oriented capabilities and orchestrates the interaction of several independently-managed components. These independently-managed components include the genome variant knowledge base, the genome database, the CDS knowledge base, a CDS controller and the electronic health record (EHR). A key design feature is that genome data can be stored separately from the EHR. This paper describes in detail: (1) each component of the architecture; (2) the interaction of the components; and (3) how the architecture attempts to overcome the challenges associated with WGS information. We believe that service-oriented CDS capabilities will be essential to using WGS information for personalized medicine.

A Proposed Clinical Decision Support Architecture Capable of Supporting Whole Genome Sequence Information

PubMed Central

Welch, Brandon M.; Rodriguez Loya, Salvador; Eilbeck, Karen; Kawamoto, Kensaku

2014-01-01

Whole genome sequence (WGS) information may soon be widely available to help clinicians personalize the care and treatment of patients. However, considerable barriers exist, which may hinder the effective utilization of WGS information in a routine clinical care setting. Clinical decision support (CDS) offers a potential solution to overcome such barriers and to facilitate the effective use of WGS information in the clinic. However, genomic information is complex and will require significant considerations when developing CDS capabilities. As such, this manuscript lays out a conceptual framework for a CDS architecture designed to deliver WGS-guided CDS within the clinical workflow. To handle the complexity and breadth of WGS information, the proposed CDS framework leverages service-oriented capabilities and orchestrates the interaction of several independently-managed components. These independently-managed components include the genome variant knowledge base, the genome database, the CDS knowledge base, a CDS controller and the electronic health record (EHR). A key design feature is that genome data can be stored separately from the EHR. This paper describes in detail: (1) each component of the architecture; (2) the interaction of the components; and (3) how the architecture attempts to overcome the challenges associated with WGS information. We believe that service-oriented CDS capabilities will be essential to using WGS information for personalized medicine. PMID:25411644

Decoupling interface effect on the phase stability of CdS thin films by van der Waals heteroepitaxy

NASA Astrophysics Data System (ADS)

Sun, Xin; Wang, Yiping; Seewald, Lucas J.; Chen, Zhizhong; Shi, Jian; Washington, Morris A.; Lu, Toh-Ming

2017-01-01

Wurtzite (W) and zinc-blende (ZB) polytypism has long been observed in epitaxial CdS thin films. The present work, based on van der Waals epitaxial CdS thin films, is an attempt to explain which crystal modification, W or ZB, is favored under different growth conditions. In this van der Waals epitaxy system where the substrate influence is considered weak, it is found that the substrate temperature plays a crucial role in determining the crystal modification of CdS, that is, W and ZB CdS are more stable at low and high ends of substrate temperature, respectively. We attribute this temperature effect to the entropy difference (SW < SZB), a conclusion well supported by the thermodynamic hard sphere model formulation of the entropy difference between hexagonal close-packed and face-centered cubic structures. By summarizing other works, we find that the entropy difference model can also be applied to large mismatched (≳3%) CdS-substrate chemical epitaxy systems but not for small mismatched (≲3%) ones. In the latter case, the energy benefit in terms of high density of bonding contributed by the substrate-film interface is believed to be too overwhelming for the intrinsic entropy difference to overcome. Furthermore, the deposition rate is found to affect the crystalline quality and strain level in CdS films but not the crystal modification of the CdS films. Last, Raman and photoluminescence spectroscopies reveal the strain behaviors in the films. The phase change from W to ZB CdS is well-correlated with the observed peak shifts in Raman and photoluminescence spectroscopies.

Toward best practice: leveraging the electronic patient record as a clinical data warehouse.

PubMed

Ledbetter, C S; Morgan, M W

2001-01-01

Automating clinical and administrative processes via an electronic patient record (EPR) gives clinicians the point-of-care tools they need to deliver better patient care. However, to improve clinical practice as a whole and then evaluate it, healthcare must go beyond basic automation and convert EPR data into aggregated, multidimensional information. Unfortunately, few EPR systems have the established, powerful analytical clinical data warehouses (CDWs) required for this conversion. This article describes how an organization can support best practice by leveraging a CDW that is fully integrated into its EPR and clinical decision support (CDS) system. The article (1) discusses the requirements for comprehensive CDS, including on-line analytical processing (OLAP) of data at both transactional and aggregate levels, (2) suggests that the transactional data acquired by an OLTP EPR system must be remodeled to support retrospective, population-based, aggregate analysis of those data, and (3) concludes that this aggregate analysis is best provided by a separate CDW system.

Rear-facing versus forward-facing child restraints: an updated assessment.

PubMed

McMurry, Timothy L; Arbogast, Kristy B; Sherwood, Christopher P; Vaca, Federico; Bull, Marilyn; Crandall, Jeff R; Kent, Richard W

2018-02-01

The National Highway Traffic Safety Administration and the American Academy of Pediatrics recommend children be placed in rear-facing child restraint systems (RFCRS) until at least age 2. These recommendations are based on laboratory biomechanical tests and field data analyses. Due to concerns raised by an independent researcher, we re-evaluated the field evidence in favour of RFCRS using the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) database. Children aged 0 or 1 year old (0-23 months) riding in either rear-facing or forward-facing child restraint systems (FFCRS) were selected from the NASS-CDS database, and injury rates were compared by seat orientation using survey-weighted χ 2 tests. In order to compare with previous work, we analysed NASS-CDS years 1988-2003, and then updated the analyses to include all available data using NASS-CDS years 1988-2015. Years 1988-2015 of NASS-CDS contained 1107 children aged 0 or 1 year old meeting inclusion criteria, with 47 of these children sustaining injuries with Injury Severity Score of at least 9. Both 0-year-old and 1-year-old children in RFCRS had lower rates of injury than children in FFCRS, but the available sample size was too small for reasonable statistical power or to allow meaningful regression controlling for covariates. Non-US field data and laboratory tests support the recommendation that children be kept in RFCRS for as long as possible, but the US NASS-CDS field data are too limited to serve as a strong statistical basis for these recommendations. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The evolution of the market for commercial computerized physician order entry and computerized decision support systems for prescribing.

PubMed

Mozaffar, Hajar; Williams, Robin; Cresswell, Kathrin; Morrison, Zoe; Bates, David W; Sheikh, Aziz

2016-03-01

To understand the evolving market of commercial off-the-shelf Computerized Physician Order Entry (CPOE) and Computerized Decision Support (CDS) applications and its effects on their uptake and implementation in English hospitals. Although CPOE and CDS vendors have been quick to enter the English market, uptake has been slow and uneven. To investigate this, the authors undertook qualitative ethnography of vendors and adopters of hospital CPOE/CDS systems in England. The authors collected data from semi-structured interviews with 11 individuals from 4 vendors, including the 2 most entrenched suppliers, and 6 adopter hospitals, and 21 h of ethnographic observation of 2 user groups, and 1 vendor event. The research and analysis was informed by insights from studies of the evolution of technology fields and the emergence of generic COTS enterprise solutions. Four key themes emerged: (1) adoption of systems that had been developed outside of England, (2) vendors' configuration and customization strategies, (3) localized adopter practices vs generic systems, and (4) unrealistic adopter demands. Evidence for our over-arching finding concerning the current immaturity of the market was derived from vendors' strategies, adopters' reactions to the technology, and policy makers' incomplete insights. The CPOE/CDS market in England is still in an emergent phase. The rapid entrance of diverse products, triggered by federal policy initiatives, has resulted in premature adoption of systems that do not yet adequately meet the needs of hospitals. Vendors and adopters lacked understanding of how to design and implement generic solutions to meet diverse user needs. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Resources and rewards for clerkship directors: how surgery compares.

PubMed

Ephgrave, Kimberly; Ferguson, Kristi; Shaaban, Aimen; Hoshi, Hisakazu

2010-01-01

Clerkship directors (CDs) are key educators and active clinicians. In 2003, the Alliance for Clinical Education published standards for CD resources and responsibilities, but how reality compares is unknown. Representatives from each core clinical disciplines' CD organizations created an electronic survey that CDs received in 2006-2007. More than 500 CDs responded, including 71 surgeons. Surgeons reported spending approximately 27% of professional time on education. Most have codirectors, so total CD effort approximates the greater than 50% Alliance for Clinical Education guidelines. No disciplines' CDs have more than one support staff as recommended. Surgeons have the least clinic time, but the most inpatient weeks and many publications. Surgery CD concerns are curricula and simulation; few believe being a CD impairs academic advancement and more than 95% believe it enhances work satisfaction. Surgery CDs are clinically active and academically productive. Although few surgery CDs have the recommended support staff, more than 95% report being a CD enhances work satisfaction.

Automation bias in electronic prescribing.

PubMed

Lyell, David; Magrabi, Farah; Raban, Magdalena Z; Pont, L G; Baysari, Melissa T; Day, Richard O; Coiera, Enrico

2017-03-16

Clinical decision support (CDS) in e-prescribing can improve safety by alerting potential errors, but introduces new sources of risk. Automation bias (AB) occurs when users over-rely on CDS, reducing vigilance in information seeking and processing. Evidence of AB has been found in other clinical tasks, but has not yet been tested with e-prescribing. This study tests for the presence of AB in e-prescribing and the impact of task complexity and interruptions on AB. One hundred and twenty students in the final two years of a medical degree prescribed medicines for nine clinical scenarios using a simulated e-prescribing system. Quality of CDS (correct, incorrect and no CDS) and task complexity (low, low + interruption and high) were varied between conditions. Omission errors (failure to detect prescribing errors) and commission errors (acceptance of false positive alerts) were measured. Compared to scenarios with no CDS, correct CDS reduced omission errors by 38.3% (p < .0001, n = 120), 46.6% (p < .0001, n = 70), and 39.2% (p < .0001, n = 120) for low, low + interrupt and high complexity scenarios respectively. Incorrect CDS increased omission errors by 33.3% (p < .0001, n = 120), 24.5% (p < .009, n = 82), and 26.7% (p < .0001, n = 120). Participants made commission errors, 65.8% (p < .0001, n = 120), 53.5% (p < .0001, n = 82), and 51.7% (p < .0001, n = 120). Task complexity and interruptions had no impact on AB. This study found evidence of AB omission and commission errors in e-prescribing. Verification of CDS alerts is key to avoiding AB errors. However, interventions focused on this have had limited success to date. Clinicians should remain vigilant to the risks of CDS failures and verify CDS.

Using Arden Syntax for the creation of a multi-patient surveillance dashboard.

PubMed

Kraus, Stefan; Drescher, Caroline; Sedlmayr, Martin; Castellanos, Ixchel; Prokosch, Hans-Ulrich; Toddenroth, Dennis

2015-10-09

Most practically deployed Arden-Syntax-based clinical decision support (CDS) modules process data from individual patients. The specification of Arden Syntax, however, would in principle also support multi-patient CDS. The patient data management system (PDMS) at our local intensive care units does not natively support patient overviews from customizable CDS routines, but local physicians indicated a demand for multi-patient tabular overviews of important clinical parameters such as key laboratory measurements. As our PDMS installation provides Arden Syntax support, we set out to explore the capability of Arden Syntax for multi-patient CDS by implementing a prototypical dashboard for visualizing laboratory findings from patient sets. Our implementation leveraged the object data type, supported by later versions of Arden, which turned out to be serviceable for representing complex input data from several patients. For our prototype, we designed a modularized architecture that separates the definition of technical operations, in particular the control of the patient context, from the actual clinical knowledge. Individual Medical Logic Modules (MLMs) for processing single patient attributes could then be developed according to well-tried Arden Syntax conventions. We successfully implemented a working dashboard prototype entirely in Arden Syntax. The architecture consists of a controller MLM to handle the patient context, a presenter MLM to generate a dashboard view, and a set of traditional MLMs containing the clinical decision logic. Our prototype could be integrated into the graphical user interface of the local PDMS. We observed that with realistic input data the average execution time of about 200ms for generating dashboard views attained applicable performance. Our study demonstrated the general feasibility of creating multi-patient CDS routines in Arden Syntax. We believe that our prototypical dashboard also suggests that such implementations can be relatively easy, and may simultaneously hold promise for sharing dashboards between institutions and reusing elementary components for additional dashboards. Copyright © 2015 Elsevier B.V. All rights reserved.

Improving Emergency Department Triage Classification with Computerized Clinical Decision Support at a Pediatric Hospital

ERIC Educational Resources Information Center

Kunisch, Joseph Martin

2012-01-01

Background: The Emergency Severity Index (ESI) is an emergency department (ED) triage classification system based on estimated patient-specific resource utilization. Rules for a computerized clinical decision support (CDS) system based on a patient's chief complaint were developed and tested using a stochastic model for predicting ESI scores.…

The Arden Syntax standard for clinical decision support: experiences and directions.

PubMed

Samwald, Matthias; Fehre, Karsten; de Bruin, Jeroen; Adlassnig, Klaus-Peter

2012-08-01

Arden Syntax is a widely recognized standard for representing clinical and scientific knowledge in an executable format. It has a history that reaches back until 1989 and is currently maintained by the Health Level 7 (HL7) organization. We created a production-ready development environment, compiler, rule engine and application server for Arden Syntax. Over the course of several years, we have applied this Arden - Syntax - based CDS system in a wide variety of clinical problem domains, such as hepatitis serology interpretation, monitoring of nosocomial infections or the prediction of metastatic events in melanoma patients. We found the Arden Syntax standard to be very suitable for the practical implementation of CDS systems. Among the advantages of Arden Syntax are its status as an actively developed HL7 standard, the readability of the syntax, and various syntactic features such as flexible list handling. A major challenge we encountered was the technical integration of our CDS systems in existing, heterogeneous health information systems. To address this issue, we are currently working on incorporating the HL7 standard GELLO, which provides a standardized interface and query language for accessing data in health information systems. We hope that these planned extensions of the Arden Syntax might eventually help in realizing the vision of a global, interoperable and shared library of clinical decision support knowledge. Copyright © 2012 Elsevier Inc. All rights reserved.

Expressing clinical data sets with openEHR archetypes: a solid basis for ubiquitous computing.

PubMed

Garde, Sebastian; Hovenga, Evelyn; Buck, Jasmin; Knaup, Petra

2007-12-01

The purpose of this paper is to analyse the feasibility and usefulness of expressing clinical data sets (CDSs) as openEHR archetypes. For this, we present an approach to transform CDS into archetypes, and outline typical problems with CDS and analyse whether some of these problems can be overcome by the use of archetypes. Literature review and analysis of a selection of existing Australian, German, other European and international CDSs; transfer of a CDS for Paediatric Oncology into openEHR archetypes; implementation of CDSs in application systems. To explore the feasibility of expressing CDS as archetypes an approach to transform existing CDSs into archetypes is presented in this paper. In case of the Paediatric Oncology CDS (which consists of 260 data items) this lead to the definition of 48 openEHR archetypes. To analyse the usefulness of expressing CDS as archetypes, we identified nine problems with CDS that currently remain unsolved without a common model underpinning the CDS. Typical problems include incompatible basic data types and overlapping and incompatible definitions of clinical content. A solution to most of these problems based on openEHR archetypes is motivated. With regard to integrity constraints, further research is required. While openEHR cannot overcome all barriers to Ubiquitous Computing, it can provide the common basis for ubiquitous presence of meaningful and computer-processable knowledge and information, which we believe is a basic requirement for Ubiquitous Computing. Expressing CDSs as openEHR archetypes is feasible and advantageous as it fosters semantic interoperability, supports ubiquitous computing, and helps to develop archetypes that are arguably of better quality than the original CDS.

Clinical Decision Support Tools for Selecting Interventions for Patients with Disabling Musculoskeletal Disorders: A Scoping Review.

PubMed

Gross, Douglas P; Armijo-Olivo, Susan; Shaw, William S; Williams-Whitt, Kelly; Shaw, Nicola T; Hartvigsen, Jan; Qin, Ziling; Ha, Christine; Woodhouse, Linda J; Steenstra, Ivan A

2016-09-01

Purpose We aimed to identify and inventory clinical decision support (CDS) tools for helping front-line staff select interventions for patients with musculoskeletal (MSK) disorders. Methods We used Arksey and O'Malley's scoping review framework which progresses through five stages: (1) identifying the research question; (2) identifying relevant studies; (3) selecting studies for analysis; (4) charting the data; and (5) collating, summarizing and reporting results. We considered computer-based, and other available tools, such as algorithms, care pathways, rules and models. Since this research crosses multiple disciplines, we searched health care, computing science and business databases. Results Our search resulted in 4605 manuscripts. Titles and abstracts were screened for relevance. The reliability of the screening process was high with an average percentage of agreement of 92.3 %. Of the located articles, 123 were considered relevant. Within this literature, there were 43 CDS tools located. These were classified into 3 main areas: computer-based tools/questionnaires (n = 8, 19 %), treatment algorithms/models (n = 14, 33 %), and clinical prediction rules/classification systems (n = 21, 49 %). Each of these areas and the associated evidence are described. The state of evidentiary support for CDS tools is still preliminary and lacks external validation, head-to-head comparisons, or evidence of generalizability across different populations and settings. Conclusions CDS tools, especially those employing rapidly advancing computer technologies, are under development and of potential interest to health care providers, case management organizations and funders of care. Based on the results of this scoping review, we conclude that these tools, models and systems should be subjected to further validation before they can be recommended for large-scale implementation for managing patients with MSK disorders.

Outcomes of clinical decision support (CDS) and correlates of CDS use for home care patients with high medication regimen complexity: A randomized trial

PubMed Central

McDonald, Margaret V.; Feldman, Penny H.; Barrón-Vayá, Yolanda; Peng, Timothy R.; Sridharan, Sridevi; Pezzin, Liliana E.

2017-01-01

Objective To assess the outcomes of a clinical decision support (CDS) intervention designed for home care patients with high medication regimen complexity (MRC) and to examine the correlates of CDS use and its relationship to patient outcomes. Method The intervention randomized nurses upon identification of an eligible patient. The CDS consisted of a computerized algorithm that identified high MRC patients, electronic clinician alerts, and a care management module. Analyses were completed on full intention to treat and intervention group-only samples. Regression-adjusted outcomes were hospitalization, emergency department use and reduction in MRC. Data sources included health records and administrative data. Results Five hundred nurses were randomized with 7,919 of their patients. Approximately 20% of the intervention group was hospitalized versus 21% in the control group; 16.5% of the intervention group had an emergency department visit versus 16.7% in the control group; and 6% in each group dropped below the high MRC threshold. No statistically significant differences were found in the intention to treat analysis. Eighty-two percent of intervention nurses used the CDS but for only 42% of their patients. Among intervention patients, CDS use (versus non-use) was associated with reduced MRC and hospitalization. CDS use was more likely among older nurses, those with higher study-patient caseload and, marginally, among salaried nurses and those with longer tenure. Significant patient characteristics were clinical conditions, payer, episode length, care continuity and race. Conclusion CDS use was limited, thus negating the impact of the intervention overall. The findings on correlates of CDS use and the relationship between CDS use and positive outcomes suggest that CDS use and outcomes could be enhanced by avoiding very short patient lengths of stay, improving continuity of care, increasing reliance on salaried nurses and/or increasing per diem nurses’ incentives to use CDS. PMID:26009977

CDS - Database Administrator's Guide

NASA Astrophysics Data System (ADS)

Day, J. P.

This guide aims to instruct the CDS database administrator in: o The CDS file system. o The CDS index files. o The procedure for assimilating a new CDS tape into the database. It is assumed that the administrator has read SUN/79.

Assessment of readiness for clinical decision support to aid laboratory monitoring of immunosuppressive care at U.S. liver transplant centers.

PubMed

Jacobs, J; Weir, C; Evans, R S; Staes, C

2014-01-01

Following liver transplantation, patients require lifelong immunosuppressive care and monitoring. Computerized clinical decision support (CDS) has been shown to improve post-transplant immunosuppressive care processes and outcomes. The readiness of transplant information systems to implement computerized CDS to support post-transplant care is unknown. a) Describe the current clinical information system functionality and manual and automated processes for laboratory monitoring of immunosuppressive care, b) describe the use of guidelines that may be used to produce computable logic and the use of computerized alerts to support guideline adherence, and c) explore barriers to implementation of CDS in U.S. liver transplant centers. We developed a web-based survey using cognitive interviewing techniques. We surveyed 119 U.S. transplant programs that performed at least five liver transplantations per year during 2010-2012. Responses were summarized using descriptive analyses; barriers were identified using qualitative methods. Respondents from 80 programs (67% response rate) completed the survey. While 98% of programs reported having an electronic health record (EHR), all programs used paper-based manual processes to receive or track immunosuppressive laboratory results. Most programs (85%) reported that 30% or more of their patients used external laboratories for routine testing. Few programs (19%) received most external laboratory results as discrete data via electronic interfaces while most (80%) manually entered laboratory results into the EHR; less than half (42%) could integrate internal and external laboratory results. Nearly all programs had guidelines regarding pre-specified target ranges (92%) or testing schedules (97%) for managing immunosuppressive care. Few programs used computerized alerting to notify transplant coordinators of out-of-range (27%) or overdue laboratory results (20%). Use of EHRs is common, yet all liver transplant programs were largely dependent on manual paper-based processes to monitor immunosuppression for post-liver transplant patients. Similar immunosuppression guidelines provide opportunities for sharing CDS once integrated laboratory data are available.

A combined paging alert and web-based instrument alters clinician behavior and shortens hospital length of stay in acute pancreatitis.

PubMed

Dimagno, Matthew J; Wamsteker, Erik-Jan; Rizk, Rafat S; Spaete, Joshua P; Gupta, Suraj; Sahay, Tanya; Costanzo, Jeffrey; Inadomi, John M; Napolitano, Lena M; Hyzy, Robert C; Desmond, Jeff S

2014-03-01

There are many published clinical guidelines for acute pancreatitis (AP). Implementation of these recommendations is variable. We hypothesized that a clinical decision support (CDS) tool would change clinician behavior and shorten hospital length of stay (LOS). Observational study, entitled, The AP Early Response (TAPER) Project. Tertiary center emergency department (ED) and hospital. Two consecutive samplings of patients having ICD-9 code (577.0) for AP were generated from the emergency department (ED) or hospital admissions. Diagnosis of AP was based on conventional Atlanta criteria. The Pre-TAPER-CDS-Tool group (5/30/06-6/22/07) had 110 patients presenting to the ED with AP per 976 ICD-9 (577.0) codes and the Post-TAPER-CDS-Tool group (5/30/06-6/22/07) had 113 per 907 ICD-9 codes (7/14/10-5/5/11). The TAPER-CDS-Tool, developed 12/2008-7/14/2010, is a combined early, automated paging-alert system, which text pages ED clinicians about a patient with AP and an intuitive web-based point-of-care instrument, consisting of seven early management recommendations. The pre- vs. post-TAPER-CDS-Tool groups had similar baseline characteristics. The post-TAPER-CDS-Tool group met two management goals more frequently than the pre-TAPER-CDS-Tool group: risk stratification (P<0.0001) and intravenous fluids >6L/1st 0-24 h (P=0.0003). Mean (s.d.) hospital LOS was significantly shorter in the post-TAPER-CDS-Tool group (4.6 (3.1) vs. 6.7 (7.0) days, P=0.0126). Multivariate analysis identified four independent variables for hospital LOS: the TAPER-CDS-Tool associated with shorter LOS (P=0.0049) and three variables associated with longer LOS: Japanese severity score (P=0.0361), persistent organ failure (P=0.0088), and local pancreatic complications (<0.0001). The TAPER-CDS-Tool is associated with changed clinician behavior and shortened hospital LOS, which has significant financial implications.

A long-term follow-up evaluation of electronic health record prescribing safety

PubMed Central

Abramson, Erika L; Malhotra, Sameer; Osorio, S Nena; Edwards, Alison; Cheriff, Adam; Cole, Curtis; Kaushal, Rainu

2013-01-01

Objective To be eligible for incentives through the Electronic Health Record (EHR) Incentive Program, many providers using older or locally developed EHRs will be transitioning to new, commercial EHRs. We previously evaluated prescribing errors made by providers in the first year following transition from a locally developed EHR with minimal prescribing clinical decision support (CDS) to a commercial EHR with robust CDS. Following system refinements, we conducted this study to assess the rates and types of errors 2 years after transition and determine the evolution of errors. Materials and methods We conducted a mixed methods cross-sectional case study of 16 physicians at an academic-affiliated ambulatory clinic from April to June 2010. We utilized standardized prescription and chart review to identify errors. Fourteen providers also participated in interviews. Results We analyzed 1905 prescriptions. The overall prescribing error rate was 3.8 per 100 prescriptions (95% CI 2.8 to 5.1). Error rates were significantly lower 2 years after transition (p<0.001 compared to pre-implementation, 12 weeks and 1 year after transition). Rates of near misses remained unchanged. Providers positively appreciated most system refinements, particularly reduced alert firing. Discussion Our study suggests that over time and with system refinements, use of a commercial EHR with advanced CDS can lead to low prescribing error rates, although more serious errors may require targeted interventions to eliminate them. Reducing alert firing frequency appears particularly important. Our results provide support for federal efforts promoting meaningful use of EHRs. Conclusions Ongoing error monitoring can allow CDS to be optimally tailored and help achieve maximal safety benefits. Clinical Trials Registration ClinicalTrials.gov, Identifier: NCT00603070. PMID:23578816

Is there cardiac risk in panic disorder? An updated systematic review.

PubMed

Caldirola, Daniela; Schruers, Koen R; Nardi, Antonio E; De Berardis, Domenico; Fornaro, Michele; Perna, Giampaolo

2016-04-01

The recognized relationship between panic disorder (PD) and cardiac disorders (CDs) is not unequivocal. We reviewed the association between PD and coronary artery disease (CAD), arrhythmias, cardiomyopathies, and sudden cardiac death. We undertook an updated systematic review, according to PRISMA guidelines. Relevant studies dating from January 1, 2000, to December 31, 2014, were identified using the PubMed database and a review of bibliographies. The psychiatric and cardiac diagnostic methodology used in each study was then to very selective inclusion criteria. Of 3044 studies, 14 on CAD, 2 on cardiomyopathies, and 1 on arrhythmias were included. Overall, the studies supported a panic-CAD association. Furthermore, in some of the studies finding no association between current full-blown PD and CAD, a broader susceptibility to panic, manifesting as past PD, current agoraphobia, or subthreshold panic symptoms, appeared to be relevant to the development of CAD. Preliminary data indicated associations between panic, arrhythmias, and cardiomyopathies. The studies were largely cross-sectional and conducted in cardiological settings. Only a few included blind settings. The clinical conditions of patients with CDs and the qualifications of raters of psychiatric diagnoses were highly heterogeneous. CDs other than CAD had been insufficiently investigated. Our review supported a relationship between PD and CDs. Given the available findings and the involvement of the cardiorespiratory system in the pathophysiology of PD, an in-depth investigation into the panic-CDs association is highly recommended. This should contribute to improved treatment and prevention of cardiac events and/or mortality, linked to PD. Copyright © 2016 Elsevier B.V. All rights reserved.

Unesco Integrated Documentation Network; Computerized Documentation System (CDS).

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Paris (France). Dept. of Documentation, Libraries, and Archives.

Intended for use by the Computerized Documentation System (CDS), the Unesco version of ISIS (Integrated Set of Information Systems)--originally developed by the International Labour Organization--was developed in 1975 and named CDS/ISIS. This system has a comprehensive collection of programs for input, management, and output, running in batch or…

NASA's Climate Data Services Initiative

NASA Astrophysics Data System (ADS)

McInerney, M.; Duffy, D.; Schnase, J. L.; Webster, W. P.

2013-12-01

Our understanding of the Earth's processes is based on a combination of observational data records and mathematical models. The size of NASA's space-based observational data sets is growing dramatically as new missions come online. However a potentially bigger data challenge is posed by the work of climate scientists, whose models are regularly producing data sets of hundreds of terabytes or more. It is important to understand that the 'Big Data' challenge of climate science cannot be solved with a single technological approach or an ad hoc assemblage of technologies. It will require a multi-faceted, well-integrated suite of capabilities that include cloud computing, large-scale compute-storage systems, high-performance analytics, scalable data management, and advanced deployment mechanisms in addition to the existing, well-established array of mature information technologies. It will also require a coherent organizational effort that is able to focus on the specific and sometimes unique requirements of climate science. Given that it is the knowledge that is gained from data that is of ultimate benefit to society, data publication and data analytics will play a particularly important role. In an effort to accelerate scientific discovery and innovation through broader use of climate data, NASA Goddard Space Flight Center's Office of Computational and Information Sciences and Technology has embarked on a determined effort to build a comprehensive, integrated data publication and analysis capability for climate science. The Climate Data Services (CDS) Initiative integrates people, expertise, and technology into a highly-focused, next-generation, one-stop climate science information service. The CDS Initiative is providing the organizational framework, processes, and protocols needed to deploy existing information technologies quickly using a combination of enterprise-level services and an expanding array of cloud services. Crucial to its effectiveness, the CDS Initiative is developing the technical expertise to move new information technologies from R&D into operational use. This combination enables full, end-to-end support for climate data publishing and data analytics, and affords the flexibility required to meet future and unanticipated needs. Current science efforts being supported by the CDS Initiative include IPPC, OBS4MIP, ANA4MIPS, MERRA II, National Climate Assessment, the Ocean Data Assimilation project, NASA Earth Exchange (NEX), and the RECOVER Burned Area Emergency Response decision support system. Service offerings include an integrated suite of classic technologies (FTP, LAS, THREDDS, ESGF, GRaD-DODS, OPeNDAP, WMS, ArcGIS Server), emerging technologies (iRODS, UVCDAT), and advanced technologies (MERRA Analytic Services, MapReduce, Ontology Services, and the CDS API). This poster will describe the CDS Initiative, provide details about the Initiative's advanced offerings, and layout the CDS Initiative's deployment roadmap.

Developing knowledge resources to support precision medicine: principles from the Clinical Pharmacogenetics Implementation Consortium (CPIC).

PubMed

Hoffman, James M; Dunnenberger, Henry M; Kevin Hicks, J; Caudle, Kelly E; Whirl Carrillo, Michelle; Freimuth, Robert R; Williams, Marc S; Klein, Teri E; Peterson, Josh F

2016-07-01

To move beyond a select few genes/drugs, the successful adoption of pharmacogenomics into routine clinical care requires a curated and machine-readable database of pharmacogenomic knowledge suitable for use in an electronic health record (EHR) with clinical decision support (CDS). Recognizing that EHR vendors do not yet provide a standard set of CDS functions for pharmacogenetics, the Clinical Pharmacogenetics Implementation Consortium (CPIC) Informatics Working Group is developing and systematically incorporating a set of EHR-agnostic implementation resources into all CPIC guidelines. These resources illustrate how to integrate pharmacogenomic test results in clinical information systems with CDS to facilitate the use of patient genomic data at the point of care. Based on our collective experience creating existing CPIC resources and implementing pharmacogenomics at our practice sites, we outline principles to define the key features of future knowledge bases and discuss the importance of these knowledge resources for pharmacogenomics and ultimately precision medicine. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

US Gateway to SIMBAD Astronomical Database

NASA Technical Reports Server (NTRS)

Eichhorn, G.

1998-01-01

During the last year the US SIMBAD Gateway Project continued to provide services like user registration to the US users of the SIMBAD database in France. User registration is required by the SIMBAD project in France. Currently, there are almost 3000 US users registered. We also provide user support by answering questions from users and handling requests for lost passwords. We have worked with the CDS SIMBAD project to provide access to the SIMBAD database to US users on an Internet address basis. This will allow most US users to access SIMBAD without having to enter passwords. This new system was installed in August, 1998. The SIMBAD mirror database at SAO is fully operational. We worked with the CDS to adapt it to our computer system. We implemented automatic updating procedures that update the database and password files daily. This mirror database provides much better access to the US astronomical community. We also supported a demonstration of the SIMBAD database at the meeting of the American Astronomical Society in January. We shipped computer equipment to the meeting and provided support for the demonstration activities at the SIMBAD booth. We continued to improve the cross-linking between the SIMBAD project and the Astro- physics Data System. This cross-linking between these systems is very much appreciated by the users of both the SIMBAD database and the ADS Abstract Service. The mirror of the SIMBAD database at SAO makes this connection faster for the US astronomers. The close cooperation between the CDS in Strasbourg and SAO, facilitated by this project, is an important part of the astronomy-wide digital library initiative called Urania. It has proven to be a model in how different data centers can collaborate and enhance the value of their products by linking with other data centers.

CDS Re Mix

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

CDS (Change Detection Systems) is a mechanism for rapid visual analysis using complex image alignment algorithms. CDS is controlled with a simple interface that has been designed for use for anyone that can operate a digital camera. A challenge of complex industrial systems like nuclear power plants is to accurately identify changes in systems, structures and components that may critically impact the operation of the facility. CDS can provide a means of early intervention before the issues evolve into safety and production challenges.

Understanding misfit strain releasing mechanisms via molecular dynamics simulations of CdTe growth on {112}zinc-blende CdS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Xiaowang; Chavez, Jose J.; Almeida, Sergio F.

Molecular dynamics simulations have been used to analyse microstructures of CdTe films grown on {112} surfaces of zinc-blende CdS. Interestingly, CdTe films grow in <331> orientations as opposed to <112> epitaxial orientations. At the CdTe-{331}/CdS-{112} interface, however, there exists an axis that is parallel to the <110> orientation of both CdS and CdTe. It is the direction orthogonal to this <110> that becomes different, being <116> for CdTe and <111> for CdS, respectively. Missing CdTe-{110} planes are found along the <110> axis, suggesting that the misfit strain is released by the conventional misfit dislocation mechanism along this axis. In themore » orthogonal axis, the misfit strain is found to be more effectively released by the new grain orientation mechanism. Our finding is supported by literature experimental observations of the change of growth direction when Cd 0.96Zn 0.04Te films are deposited on GaAs. Lastly the analyses of energetics clearly demonstrate the cause for the formation of the new orientation, and the insights gained from our studies can help understand the grain structures experimentally observed in lattice mismatched systems.« less

Understanding misfit strain releasing mechanisms via molecular dynamics simulations of CdTe growth on {112}zinc-blende CdS

DOE PAGES

Zhou, Xiaowang; Chavez, Jose J.; Almeida, Sergio F.; ...

2016-07-25

Molecular dynamics simulations have been used to analyse microstructures of CdTe films grown on {112} surfaces of zinc-blende CdS. Interestingly, CdTe films grow in <331> orientations as opposed to <112> epitaxial orientations. At the CdTe-{331}/CdS-{112} interface, however, there exists an axis that is parallel to the <110> orientation of both CdS and CdTe. It is the direction orthogonal to this <110> that becomes different, being <116> for CdTe and <111> for CdS, respectively. Missing CdTe-{110} planes are found along the <110> axis, suggesting that the misfit strain is released by the conventional misfit dislocation mechanism along this axis. In themore » orthogonal axis, the misfit strain is found to be more effectively released by the new grain orientation mechanism. Our finding is supported by literature experimental observations of the change of growth direction when Cd 0.96Zn 0.04Te films are deposited on GaAs. Lastly the analyses of energetics clearly demonstrate the cause for the formation of the new orientation, and the insights gained from our studies can help understand the grain structures experimentally observed in lattice mismatched systems.« less

Incorporating INTERACT II Clinical Decision Support Tools into Nursing Home Health Information Technology

PubMed Central

Handler, Steven M.; Sharkey, Siobhan S.; Hudak, Sandra; Ouslander, Joseph G.

2012-01-01

A substantial reduction in hospitalization rates has been associated with the implementation of the Interventions to Reduce Acute Care Transfers (INTERACT) quality improvement intervention using the accompanying paper-based clinical practice tools (INTERACT II). There is significant potential to further increase the impact of INTERACT by integrating INTERACT II tools into nursing home (NH) health information technology (HIT) via standalone or integrated clinical decision support (CDS) systems. This article highlights the process of translating INTERACT II tools from paper to NH HIT. The authors believe that widespread dissemination and integration of INTERACT II CDS tools into various NH HIT products could lead to sustainable improvement in resident and clinician process and outcome measures, including enhanced interclinician communication and a reduction in potentially avoidable hospitalizations. PMID:22267955

Comparative effectiveness of childhood obesity interventions in pediatric primary care: a cluster-randomized clinical trial.

PubMed

Taveras, Elsie M; Marshall, Richard; Kleinman, Ken P; Gillman, Matthew W; Hacker, Karen; Horan, Christine M; Smith, Renata L; Price, Sarah; Sharifi, Mona; Rifas-Shiman, Sheryl L; Simon, Steven R

2015-06-01

Evidence of effective treatment of childhood obesity in primary care settings is limited. To examine the extent to which computerized clinical decision support (CDS) delivered to pediatric clinicians at the point of care of obese children, with or without individualized family coaching, improved body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) and quality of care. We conducted a cluster-randomized, 3-arm clinical trial. We enrolled 549 children aged 6 to 12 years with a BMI at the 95% percentile or higher from 14 primary care practices in Massachusetts from October 1, 2011, through June 30, 2012. Patients were followed up for 1 year (last follow-up, August 30, 2013). In intent-to-treat analyses, we used linear mixed-effects models to account for clustering by practice and within each person. In 5 practices randomized to CDS, pediatric clinicians received decision support on obesity management, and patients and their families received an intervention for self-guided behavior change. In 5 practices randomized to CDS + coaching, decision support was augmented by individualized family coaching. The remaining 4 practices were randomized to usual care. Smaller age-associated change in BMI and the Healthcare Effectiveness Data and Information Set (HEDIS) performance measures for obesity during the 1-year follow-up. At baseline, mean (SD) patient age and BMI were 9.8 (1.9) years and 25.8 (4.3), respectively. At 1 year, we obtained BMI from 518 children (94.4%) and HEDIS measures from 491 visits (89.4%). The 3 randomization arms had different effects on BMI over time (P = .04). Compared with the usual care arm, BMI increased less in children in the CDS arm during 1 year (-0.51 [95% CI, -0.91 to -0.11]). The CDS + coaching arm had a smaller magnitude of effect (-0.34 [95% CI, -0.75 to 0.07]). We found substantially greater achievement of childhood obesity HEDIS measures in the CDS arm (adjusted odds ratio, 2.28 [95% CI, 1.15-4.53]) and CDS + coaching arm (adjusted odds ratio, 2.60 [95% CI, 1.25-5.41]) and higher use of HEDIS codes for nutrition or physical activity counseling (CDS arm, 45%; CDS + coaching arm, 25%; P < .001 compared with usual care arm). An intervention that included computerized CDS for pediatric clinicians and support for self-guided behavior change for families resulted in improved childhood BMI. Both interventions improved the quality of care for childhood obesity. clinicaltrials.gov Identifier: NCT01537510.

Census Data System of the Management Information System for Occupational Education: Guidelines and Instructions for Reporting. CDS Document No. 1.

ERIC Educational Resources Information Center

Management and Information System for Occupational Education, Winchester, MA.

The MISOE Census Data System (CDS) is one of two major subsystems of an integrated management information system (MISOE), which was developed to provide occupational education managers with comprehensive data on which to base rational management decisions. Essentially, CDS contains descriptive information systematically structured in a manner…

Standards for reporting randomized controlled trials in medical informatics: a systematic review of CONSORT adherence in RCTs on clinical decision support

PubMed Central

Berntsen, G; Lassen, K; Bellika, J G; Wootton, R; Lindsetmo, R O

2011-01-01

Introduction The Consolidated Standards for Reporting Trials (CONSORT) were published to standardize reporting and improve the quality of clinical trials. The objective of this study is to assess CONSORT adherence in randomized clinical trials (RCT) of disease specific clinical decision support (CDS). Methods A systematic search was conducted of the Medline, EMBASE, and Cochrane databases. RCTs on CDS were assessed against CONSORT guidelines and the Jadad score. Result 32 of 3784 papers identified in the primary search were included in the final review. 181 702 patients and 7315 physicians participated in the selected trials. Most trials were performed in primary care (22), including 897 general practitioner offices. RCTs assessing CDS for asthma (4), diabetes (4), and hyperlipidemia (3) were the most common. Thirteen CDS systems (40%) were implemented in electronic medical records, and 14 (43%) provided automatic alerts. CONSORT and Jadad scores were generally low; the mean CONSORT score was 30.75 (95% CI 27.0 to 34.5), median score 32, range 21–38. Fourteen trials (43%) did not clearly define the study objective, and 11 studies (34%) did not include a sample size calculation. Outcome measures were adequately identified and defined in 23 (71%) trials; adverse events or side effects were not reported in 20 trials (62%). Thirteen trials (40%) were of superior quality according to the Jadad score (≥3 points). Six trials (18%) reported on long-term implementation of CDS. Conclusion The overall quality of reporting RCTs was low. There is a need to develop standards for reporting RCTs in medical informatics. PMID:21803926

Cross-vendor evaluation of key user-defined clinical decision support capabilities: a scenario-based assessment of certified electronic health records with guidelines for future development

PubMed Central

Wright, Adam; Sittig, Dean F

2015-01-01

Objective Clinical decision support (CDS) is essential for delivery of high-quality, cost-effective, and safe healthcare. The authors sought to evaluate the CDS capabilities across electronic health record (EHR) systems. Methods We evaluated the CDS implementation capabilities of 8 Office of the National Coordinator for Health Information Technology Authorized Certification Body (ONC-ACB)-certified EHRs. Within each EHR, the authors attempted to implement 3 user-defined rules that utilized the various data and logic elements expected of typical EHRs and that represented clinically important evidenced-based care. The rules were: 1) if a patient has amiodarone on his or her active medication list and does not have a thyroid-stimulating hormone (TSH) result recorded in the last 12 months, suggest ordering a TSH; 2) if a patient has a hemoglobin A1c result >7% and does not have diabetes on his or her problem list, suggest adding diabetes to the problem list; and 3) if a patient has coronary artery disease on his or her problem list and does not have aspirin on the active medication list, suggest ordering aspirin. Results Most evaluated EHRs lacked some CDS capabilities; 5 EHRs were able to implement all 3 rules, and the remaining 3 EHRs were unable to implement any of the rules. One of these did not allow users to customize CDS rules at all. The most frequently found shortcomings included the inability to use laboratory test results in rules, limit rules by time, use advanced Boolean logic, perform actions from the alert interface, and adequately test rules. Conclusion Significant improvements in the EHR certification and implementation procedures are necessary. PMID:26104739

Emergency physicians' knowledge and attitudes of clinical decision support in the electronic health record: a survey-based study.

PubMed

Ballard, Dustin W; Rauchwerger, Adina S; Reed, Mary E; Vinson, David R; Mark, Dustin G; Offerman, Steven R; Chettipally, Uli K; Graetz, Ilana; Dayan, Peter; Kuppermann, Nathan

2013-04-01

The objective was to investigate clinician knowledge of and attitudes toward clinical decision support (CDS) and its incorporation into the electronic health record (EHR). This was an electronic survey of emergency physicians (EPs) within an integrated health care delivery system that uses a complete EHR. Randomly assigned respondents completed one of two questionnaires, both including a hypothetical vignette and self-reported knowledge of and attitudes about CDS. One vignette version included CDS, and the other did not (NCDS). The vignette described a scenario in which a cranial computed tomography (CCT) is not recommended by validated prediction rules (the Pediatric Emergency Care Applied Research Network [PECARN] rules). In both survey versions, subjects responded first with their likely approach to evaluation and then again after receiving either CDS (the PECARN prediction rules) or no additional support. Descriptive statistics were used for self-reported responses and multivariate logistic regression was used to identify predictors of self-reported knowledge and use of the PECARN rules, as well as use of vignette responses. There were 339 respondents (68% response rate), with 172 of 339 (51%) randomized to the CDS version. Initially, 25% of respondents to each version indicated they would order CCTs. After CDS, 30 of 43 (70%) of respondents who initially would order CCTs changed their management decisions to no CCT versus two of 41 (5%) with the NCDS version (chi-square, p = 0.003). In response to self-report questions, 81 of 338 respondents (24%) reported having never heard of the PECARN prediction rules, 122 of 338 (36%) were aware of the rules but not their specifics, and 135 of 338 (40%) reported knowing the rules and their specifics. Respondents agreed with favorable statements about CDS (75% to 96% agreement across seven statements) and approaches to its implementation into the EHR (60% to 93% agreement across seven statements). In multivariable analyses, EPs with tenure of 5 to 14 years (odds ratio [AOR] = 0.51, 95% confidence interval [CI] = 0.30 to 0.86) and for 15 years or more (AOR = 0.37, 95% CI = 0.20 to 0.70) were significantly less likely to report knowing the specifics of the PECARN prediction rules compared with EPs who practiced for fewer than 5 years. In addition, in the initial vignette responses (across both versions), physicians with ≥15 years of ED tenure compared to those with fewer than 5 years of experience (AOR = 0.30, 95% CI = 0.13 to 0.69), and those reporting knowing the specifics of the PECARN prediction rules were less likely to order CCTs (AOR = 0.53, 95% CI = 0.30 to 0.92). EPs incorporated pediatric head trauma CDS via the EHR into their clinical judgment in a hypothetical scenario and reported favorable opinions of CDS in general and their inclusion into the EHR. © 2013 by the Society for Academic Emergency Medicine.

The Financial Management System: A Pivotal Tool for Fiscal Viability. CDS Spotlight. ECAR Research Bulletin

ERIC Educational Resources Information Center

Lang, Leah; Pirani, Judith A.

2014-01-01

This spotlight focuses on data from the 2013 CDS to better understand how higher education institutions approach financial management systems. Information provided for this spotlight was derived from Module 8 of Core Data Service (CDS), which asked several questions regarding information systems and applications. Responses from 525 institutions…

SSBRP User Operations Facility (UOF) Overview and Development Strategy

NASA Technical Reports Server (NTRS)

Picinich, Lou; Stone, Thom; Sun, Charles; Windrem, May; Givens, John J. (Technical Monitor)

1995-01-01

This paper will present the Space Station Biological Research Project (SSBRP) User Operations Facility (UOF) architecture and development strategy. A major element of the UOF at NASA Ames Research Center, the Communication and Data System (CDS) will be the primary focus of the discussions. CDS operational, telescience, security, and development objectives will be discussed along with CDS implementation strategy. The implementation strategy discussions will include: Object Oriented Analysis & Design, System & Software Prototyping, and Technology Utilization. A CDS design overview that includes: CDS Context Diagram, CDS Architecture, Object Models, Use Cases, and User Interfaces will also be presented. CDS development brings together "cutting edge" technologies and techniques such as: object oriented development, network security, multimedia networking, web-based data distribution, JAVA, and graphical user interfaces. Use of these "cutting edge" technologies and techniques translates directly to lower development and operations costs.

Cascade Distillation System Development

NASA Technical Reports Server (NTRS)

Callahan, Michael R.; Sargushingh, Miriam; Shull, Sarah

2014-01-01

NASA's Advanced Exploration Systems (AES) Life Support System (LSS) Project is chartered with de-veloping advanced life support systems that will ena-ble NASA human exploration beyond low Earth orbit (LEO). The goal of AES is to increase the affordabil-ity of long-duration life support missions, and to re-duce the risk associated with integrating and infusing new enabling technologies required to ensure mission success. Because of the robust nature of distillation systems, the AES LSS Project is pursuing develop-ment of the Cascade Distillation Subsystem (CDS) as part of its technology portfolio. Currently, the system is being developed into a flight forward Generation 2.0 design.

Utilization of Condensed Distillers Solubles as Nutrient Supplement for Production of Nisin and Lactic Acid from Whey

NASA Astrophysics Data System (ADS)

Liu, Chuanbin; Hu, Bo; Chen, Shulin; Glass, Richard W.

The major challenge associated with the rapid growth of the ethanol industry is the usage of the coproducts, i.e., condensed distillers solubles (CDS) and distillers dried grains, which are currently sold as animal feed supplements. As the growth of the livestock industries remains flat, alternative usage of these coproducts is urgently needed. CDS is obtained after the removal of ethanol by distillation from the yeast fermentation of a grain or a grain mixture by condensing the thin stillage fraction to semisolid. In this work, CDS was first characterized and yeast biomass was proven to be the major component of CDS. CDS contained 7.50% crude protein but with only 42% of that protein being water soluble. Then, CDS was applied as a nutrient supplement for simultaneous production of nisin and lactic acid by Lactococcus lactis subsp. lactis (ATCC 11454). Although CDS was able to support bacteria growth and nisin production, a strong inhibition was observed when CDS was overdosed. This may be caused by the existence of the major ethanol fermentation byproducts, especially lactate and acetate, in CDS. In the final step, the CDS based medium composition for nisin and lactic acid production was optimized using response surface methodology.

The Influence of Child-Directed Speech on Word Learning and Comprehension.

PubMed

Foursha-Stevenson, Cassandra; Schembri, Taylor; Nicoladis, Elena; Eriksen, Cody

2017-04-01

This paper describes an investigation into the function of child-directed speech (CDS) across development. In the first experiment, 10-21-month-olds were presented with familiar words in CDS and trained on novel words in CDS or adult-directed speech (ADS). All children preferred the matching display for familiar words. However, only older toddlers in the CDS condition preferred the matching display for novel words. In Experiment 2, children 3-6 years of age were presented with a sentence comprehension task in CDS or ADS. Older children performed better overall than younger children with 5- and 6-year-olds performing above chance regardless of speech condition, while 3- and 4-year-olds only performed above chance when the sentences were presented in CDS. These findings provide support for the theory that CDS is most effective at the beginning of acquisition for particular constructions (e.g. vocabulary acquisition, syntactic comprehension) rather than at a particular age or for a particular task.

Recommendations for selecting drug-drug interactions for clinical decision support.

PubMed

Tilson, Hugh; Hines, Lisa E; McEvoy, Gerald; Weinstein, David M; Hansten, Philip D; Matuszewski, Karl; le Comte, Marianne; Higby-Baker, Stefanie; Hanlon, Joseph T; Pezzullo, Lynn; Vieson, Kathleen; Helwig, Amy L; Huang, Shiew-Mei; Perre, Anthony; Bates, David W; Poikonen, John; Wittie, Michael A; Grizzle, Amy J; Brown, Mary; Malone, Daniel C

2016-04-15

Recommendations for including drug-drug interactions (DDIs) in clinical decision support (CDS) are presented. A conference series was conducted to improve CDS for DDIs. A work group consisting of 20 experts in pharmacology, drug information, and CDS from academia, government agencies, health information vendors, and healthcare organizations was convened to address (1) the process to use for developing and maintaining a standard set of DDIs, (2) the information that should be included in a knowledge base of standard DDIs, (3) whether a list of contraindicated drug pairs can or should be established, and (4) how to more intelligently filter DDI alerts. We recommend a transparent, systematic, and evidence-driven process with graded recommendations by a consensus panel of experts and oversight by a national organization. We outline key DDI information needed to help guide clinician decision-making. We recommend judicious classification of DDIs as contraindicated and more research to identify methods to safely reduce repetitive and less-relevant alerts. An expert panel with a centralized organizer or convener should be established to develop and maintain a standard set of DDIs for CDS in the United States. The process should be evidence driven, transparent, and systematic, with feedback from multiple stakeholders for continuous improvement. The scope of the expert panel's work should be carefully managed to ensure that the process is sustainable. Support for research to improve DDI alerting in the future is also needed. Adoption of these steps may lead to consistent and clinically relevant content for interruptive DDIs, thus reducing alert fatigue and improving patient safety. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Automating Guidelines for Clinical Decision Support: Knowledge Engineering and Implementation.

PubMed

Tso, Geoffrey J; Tu, Samson W; Oshiro, Connie; Martins, Susana; Ashcraft, Michael; Yuen, Kaeli W; Wang, Dan; Robinson, Amy; Heidenreich, Paul A; Goldstein, Mary K

2016-01-01

As utilization of clinical decision support (CDS) increases, it is important to continue the development and refinement of methods to accurately translate the intention of clinical practice guidelines (CPG) into a computable form. In this study, we validate and extend the 13 steps that Shiffman et al. 5 identified for translating CPG knowledge for use in CDS. During an implementation project of ATHENA-CDS, we encoded complex CPG recommendations for five common chronic conditions for integration into an existing clinical dashboard. Major decisions made during the implementation process were recorded and categorized according to the 13 steps. During the implementation period, we categorized 119 decisions and identified 8 new categories required to complete the project. We provide details on an updated model that outlines all of the steps used to translate CPG knowledge into a CDS integrated with existing health information technology.

Service oriented architecture for clinical decision support: a systematic review and future directions.

PubMed

Loya, Salvador Rodriguez; Kawamoto, Kensaku; Chatwin, Chris; Huser, Vojtech

2014-12-01

The use of a service-oriented architecture (SOA) has been identified as a promising approach for improving health care by facilitating reliable clinical decision support (CDS). A review of the literature through October 2013 identified 44 articles on this topic. The review suggests that SOA related technologies such as Business Process Model and Notation (BPMN) and Service Component Architecture (SCA) have not been generally adopted to impact health IT systems' performance for better care solutions. Additionally, technologies such as Enterprise Service Bus (ESB) and architectural approaches like Service Choreography have not been generally exploited among researchers and developers. Based on the experience of other industries and our observation of the evolution of SOA, we found that the greater use of these approaches have the potential to significantly impact SOA implementations for CDS.

A novel fluorescent retrograde neural tracer: cholera toxin B conjugated carbon dots

NASA Astrophysics Data System (ADS)

Zhou, Nan; Hao, Zeyu; Zhao, Xiaohuan; Maharjan, Suraj; Zhu, Shoujun; Song, Yubin; Yang, Bai; Lu, Laijin

2015-09-01

The retrograde neuroanatomical tracing method is a key technique to study the complex interconnections of the nervous system. Traditional tracers have several drawbacks, including time-consuming immunohistochemical or immunofluorescent staining procedures, rapid fluorescence quenching and low fluorescence intensity. Carbon dots (CDs) have been widely used as a fluorescent bio-probe due to their ultrasmall size, excellent optical properties, chemical stability, biocompatibility and low toxicity. Herein, we develop a novel fluorescent neural tracer: cholera toxin B-carbon dot conjugates (CTB-CDs). It can be taken up and retrogradely transported by neurons in the peripheral nervous system of rats. Our results show that CTB-CDs possess high photoluminescence intensity, good optical stability, a long shelf-life and non-toxicity. Tracing with CTB-CDs is a direct and more economical way of performing retrograde labelling experiments. Therefore, CTB-CDs are reliable fluorescent retrograde tracers.The retrograde neuroanatomical tracing method is a key technique to study the complex interconnections of the nervous system. Traditional tracers have several drawbacks, including time-consuming immunohistochemical or immunofluorescent staining procedures, rapid fluorescence quenching and low fluorescence intensity. Carbon dots (CDs) have been widely used as a fluorescent bio-probe due to their ultrasmall size, excellent optical properties, chemical stability, biocompatibility and low toxicity. Herein, we develop a novel fluorescent neural tracer: cholera toxin B-carbon dot conjugates (CTB-CDs). It can be taken up and retrogradely transported by neurons in the peripheral nervous system of rats. Our results show that CTB-CDs possess high photoluminescence intensity, good optical stability, a long shelf-life and non-toxicity. Tracing with CTB-CDs is a direct and more economical way of performing retrograde labelling experiments. Therefore, CTB-CDs are reliable fluorescent retrograde tracers. Electronic supplementary information (ESI) available: PL spectra of CTB; absorption spectra of dialysate; fluorescence signal and immunohistochemical staining of CTB-CDs in L4 DRG. See DOI: 10.1039/c5nr04361a

Adaptability of optimization concept in the context of cryogenic distribution for superconducting magnets of fusion machine

NASA Astrophysics Data System (ADS)

Sarkar, Biswanath; Bhattacharya, Ritendra Nath; Vaghela, Hitensinh; Shah, Nitin Dineshkumar; Choukekar, Ketan; Badgujar, Satish

2012-06-01

Cryogenic distribution system (CDS) plays a vital role for reliable operation of largescale fusion machines in a Tokamak configuration. Managing dynamic heat loads from the superconducting magnets, namely, toroidal field, poloidal field, central solenoid and supporting structure is the most important function of the CDS along with the static heat loads. Two concepts are foreseen for the configuration of the CDS: singular distribution and collective distribution. In the first concept, each magnet is assigned with one distribution box having its own sub-cooler bath. In the collective concept, it is possible to share one common bath for more than one magnet system. The case study has been performed with an identical dynamic heat load profile applied to both concepts in the same time domain. The choices of a combined system from the magnets are also part of the study without compromising the system functionality. Process modeling and detailed simulations have been performed for both the options using Aspen HYSYS®. Multiple plasma pulses per day have been considered to verify the residual energy deposited in the superconducting magnets at the end of the plasma pulse. Preliminary 3D modeling using CATIA® has been performed along with the first level of component sizing.

“Reducing unnecessary testing in a CPOE system through implementation of a targeted CDS intervention”

PubMed Central

2013-01-01

Background We describe and evaluate the development and use of a Clinical Decision Support (CDS) intervention; an alert, in response to an identified medical error of overuse of a diagnostic laboratory test in a Computerized Physician Order Entry (CPOE) system. CPOE with embedded CDS has been shown to improve quality of care and reduce medical errors. CPOE can also improve resource utilization through more appropriate use of laboratory tests and diagnostic studies. Observational studies are necessary in order to understand how these technologies can be successfully employed by healthcare providers. Methods The error was identified by the Test Utilization Committee (TUC) in September, 2008 when they noticed critical care patients were being tested daily, and sometimes twice daily, for B-Type Natriuretic Peptide (BNP). Repeat and/or serial BNP testing is inappropriate for guiding the management of heart failure and may be clinically misleading. The CDS intervention consists of an expert rule that searches the system for a BNP lab value on the patient. If there is a value and the value is within the current hospital stay, an advisory is displayed to the ordering clinician. In order to isolate the impact of this intervention on unnecessary BNP testing we applied multiple regression analysis to the sample of 41,306 patient admissions with at least one BNP test at LVHN between January, 2008 and September, 2011. Results Our regression results suggest the CDS intervention reduced BNP orders by 21% relative to the mean. The financial impact of the rule was also significant. Multiplying by the direct supply cost of $28.04 per test, the intervention saved approximately $92,000 per year. Conclusions The use of alerts has great positive potential to improve care, but should be used judiciously and in the appropriate environment. While these savings may not be generalizable to other interventions, the experience at LVHN suggests that appropriately designed and carefully implemented CDS interventions can have a substantial impact on the efficiency of care provision. PMID:23566021

Improved delivery through biological membranes. XXXL: Solubilization and stabilization of an estradiol chemical delivery system by modified beta-cyclodextrins.

PubMed

Brewster, M E; Estes, K S; Loftsson, T; Perchalski, R; Derendorf, H; Mullersman, G; Bodor, N

1988-11-01

A dihydropyridine in equilibrium pyridinium salt chemical delivery system (CDS) for estradiol (E2CDS) was complexed with various modified beta-cyclodextrins including hydroxyethyl-beta-cyclodextrin (HECD), hydroxypropyl-beta-cyclodextrin (HPCD), and heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DMCD). Complex formation with all of these cyclodextrins resulted in dramatic increases in the water solubility of E2CDS. Studies on the complex of E2CDS and HPCD (E2CDS-CD) indicated that the encapsulated estrogen was approximately four times more stable than the unmanipulated CDS, producing an estimated half-life of degradation of 4 years compared with 1.2 years for the uncomplexed drug at room temperature. The complexation of E2CDS and HPCD also stabilized the dihydronicotinate in solutions containing potassium ferricyanide. This formulation was shown to be equivalent to E2CDS in dimethyl sulfoxide in delivering the oxidized, estradiol precursor (E2Q+) to the brain, and also produced similar biological responses; these included decreased luteinizing hormone (LH) secretion and a decrease in the rate of weight gain in castrated female rats.

BI Reporting, Data Warehouse Systems, and Beyond. CDS Spotlight Report. Research Bulletin

ERIC Educational Resources Information Center

Lang, Leah; Pirani, Judith A.

2014-01-01

This Spotlight focuses on data from the 2013 Core Data Service [CDS] to better understand how higher education institutions approach business intelligence (BI) reporting and data warehouse systems (see the Sidebar for definitions). Information provided for this Spotlight was derived from Module 8 of CDS, which contains several questions regarding…

A Bridging Opportunities Work-frame to develop mobile applications for clinical decision making

PubMed Central

van Rooij, Tibor; Rix, Serena; Moore, James B; Marsh, Sharon

2015-01-01

Background: Mobile applications (apps) providing clinical decision support (CDS) may show the greatest promise when created by and for frontline clinicians. Our aim was to create a generic model enabling healthcare providers to direct the development of CDS apps. Methods: We combined Change Management with a three-tier information technology architecture to stimulate CDS app development. Results: A Bridging Opportunities Work-frame model was developed. A test case was used to successfully develop an app. Conclusion: Healthcare providers can re-use this globally applicable model to actively create and manage regional decision support applications to translate evidence-based medicine in the use of emerging medication or novel treatment regimens. PMID:28031883

CdS loaded on coal based activated carbon nanofibers with enhanced photocatalytic property

NASA Astrophysics Data System (ADS)

Guo, Jixi; Guo, Mingxi; Jia, Dianzeng; Song, Xianli; Tong, Fenglian

2016-08-01

The coal based activated carbon nanofibers (CBACFs) were prepared by electrospinning a mixture of polyacrylonitrile (PAN) and acid treated coal. Cadmium sulfide (CdS) nanoparticles loaded on CBACFs were fabricated by solvothermal method. The obtained samples were characterized by FESEM, TEM, and XRD. The results reveal that the CdS nanoparticles are homogeneously dispersed on the surfaces of CBACFs. The CdS/CBACFs nanocomposites exhibited higher photoactivity for photodegradation of methyl blue (MB) under visible light irradiation than pure CdS nanoparticles. CBACFs can be used as low cost support materials for the preparation of nanocomposites with high photocatalytic activity.

A Dynamic Approach to Make CDS/ISIS Databases Interoperable over the Internet Using the OAI Protocol

ERIC Educational Resources Information Center

Jayakanth, F.; Maly, K.; Zubair, M.; Aswath, L.

2006-01-01

Purpose: A dynamic approach to making legacy databases, like CDS/ISIS, interoperable with OAI-compliant digital libraries (DLs). Design/methodology/approach: There are many bibliographic databases that are being maintained using legacy database systems. CDS/ISIS is one such legacy database system. It was designed and developed specifically for…

Lung Cancer Assistant: a hybrid clinical decision support application for lung cancer care.

PubMed

Sesen, M Berkan; Peake, Michael D; Banares-Alcantara, Rene; Tse, Donald; Kadir, Timor; Stanley, Roz; Gleeson, Fergus; Brady, Michael

2014-09-06

Multidisciplinary team (MDT) meetings are becoming the model of care for cancer patients worldwide. While MDTs have improved the quality of cancer care, the meetings impose substantial time pressure on the members, who generally attend several such MDTs. We describe Lung Cancer Assistant (LCA), a clinical decision support (CDS) prototype designed to assist the experts in the treatment selection decisions in the lung cancer MDTs. A novel feature of LCA is its ability to provide rule-based and probabilistic decision support within a single platform. The guideline-based CDS is based on clinical guideline rules, while the probabilistic CDS is based on a Bayesian network trained on the English Lung Cancer Audit Database (LUCADA). We assess rule-based and probabilistic recommendations based on their concordances with the treatments recorded in LUCADA. Our results reveal that the guideline rule-based recommendations perform well in simulating the recorded treatments with exact and partial concordance rates of 0.57 and 0.79, respectively. On the other hand, the exact and partial concordance rates achieved with probabilistic results are relatively poorer with 0.27 and 0.76. However, probabilistic decision support fulfils a complementary role in providing accurate survival estimations. Compared to recorded treatments, both CDS approaches promote higher resection rates and multimodality treatments.

Measuring Clinical Decision Support Influence on Evidence-Based Nursing Practice.

PubMed

Cortez, Susan; Dietrich, Mary S; Wells, Nancy

2016-07-01

To measure the effect of clinical decision support (CDS) on oncology nurse evidence-based practice (EBP).
. Longitudinal cluster-randomized design.
. Four distinctly separate oncology clinics associated with an academic medical center.
. The study sample was comprised of randomly selected data elements from the nursing documentation software. The data elements were patient-reported symptoms and the associated nurse interventions. The total sample observations were 600, derived from a baseline, posteducation, and postintervention sample of 200 each (100 in the intervention group and 100 in the control group for each sample).
. The cluster design was used to support randomization of the study intervention at the clinic level rather than the individual participant level to reduce possible diffusion of the study intervention. An elongated data collection cycle (11 weeks) controlled for temporary increases in nurse EBP related to the education or CDS intervention.
. The dependent variable was the nurse evidence-based documentation rate, calculated from the nurse-documented interventions. The independent variable was the CDS added to the nursing documentation software.
. The average EBP rate at baseline for the control and intervention groups was 27%. After education, the average EBP rate increased to 37%, and then decreased to 26% in the postintervention sample. Mixed-model linear statistical analysis revealed no significant interaction of group by sample. The CDS intervention did not result in an increase in nurse EBP.
. EBP education increased nurse EBP documentation rates significantly but only temporarily. Nurses may have used evidence in practice but may not have documented their interventions.
. More research is needed to understand the complex relationship between CDS, nursing practice, and nursing EBP intervention documentation. CDS may have a different effect on nurse EBP, physician EBP, and other medical professional EBP.

Working at the intersection of context, culture, and technology: Provider perspectives on antimicrobial stewardship in the emergency department using electronic health record clinical decision support.

PubMed

Chung, Phillip; Scandlyn, Jean; Dayan, Peter S; Mistry, Rakesh D

2017-11-01

Antibiotic stewardship programs (ASPs) have not been fully developed for the emergency department (ED), in part the result of the barriers characteristic of this setting. Electronic health record-based clinical decision support (EHR CDS) represents a promising strategy to implement ASPs in the ED. We aimed to determine the cultural beliefs and structural barriers and facilitators to implementation of antimicrobial stewardship in the pediatric ED using EHR CDS. Interviews and focus groups were conducted with hospital and ED leadership, attending ED physicians, nurse practitioners, physician assistants, and residents at a single health system in Colorado. We reviewed and coded the data using constant comparative analysis and framework analysis until a final set of themes emerged. Two dominant perceptions shaped providers' perspectives on ASPs in the ED and EHR CDS: (1) maintaining workflow efficiency and (2) constrained decision-making autonomy. Clinicians identified structural barriers to ASPs, such as pace of the ED, and various beliefs that shaped patterns of practice, including accommodating the prescribing decisions of other providers and managing parental expectations. Recommendations to enhance uptake focused on designing a simple yet flexible user interface, providing clinicians with performance data, and on-boarding clinicians to enhance buy-in. Developing a successful ED-based ASP using EHR CDS should attend to technologic needs, the institutional context, and the cultural beliefs of practice associated with providers' antibiotic prescribing. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Immobilization effects on the photocatalytic activity of CdS quantum Dots-Horseradish peroxidase hybrid nanomaterials.

PubMed

Iñarritu, Iker; Torres, Eduardo; Topete, Antonio; Campos-Terán, José

2017-11-15

The potential use of hybrid nanomaterials based on inorganic optically active nanoparticles known as quantum dots (QDs) and horseradish peroxidase (HRP) has been proposed by several authors as light-controllable nanocatalyzers, moreover, the immobilization within or over silica based supports represents an advantage over bulk-dispersed systems. However, the implications of the immobilization of such hybrid photoactivatable catalyzing systems have not been clarified with detail. Here, we present a thorough study of the functional photoactive efficiency and recycling of immobilized CdS QDs and HRP systems with different configurations, immobilized over silanized silica quartz crystal microbalance (QCM) sensors, allowing an accurate measure of the immobilized mass of each component and its correlation with the initial reaction rate of conversion of Amplex Red (AR) to resorufin. As well, the conversion efficiency is compared between the different systems and also to non-immobilized QD-HRP complexed systems. Copyright © 2017 Elsevier Inc. All rights reserved.

CERA: Clerkships Need National Curricula on Care Delivery, Awareness of Their NCC Gaps.

PubMed

Cochella, Susan; Liaw, Winston; Binienda, Juliann; Hustedde, Carol

2016-06-01

The Society of Teachers of Family Medicine's (STFM) National Clerkship Curriculum (NCC) was created to standardize and improve teaching of a minimum core curriculum in family medicine clerkships, promoting the Triple Aim of better care and population health at lower cost. It includes competencies all clerkships should teach and tools to support clerkship directors (CDs). This 2014 CERA survey of clerkship directors is one of several needs assessments that guide STFM's NCC Editorial Board in targeting improvements and peer-review processes. CERA's 2014 survey of CDs was sent to all 137 CDs at US and Canadian allopathic medical schools. Primary aims included: (1) Identify curricular topics of greatest need, (2) Inventory the percent of family medicine clerkships teaching each NCC topic, and (3) Determine if longitudinal or blended clerkship have unique needs. This survey also assessed use of NCC to advocate for teaching resources and collaborate with colleagues at other institutions. Ninety-one percent of CDs completed the survey. Sixty-four percent reported their clerkship covers all of the NCC minimum core, but on detailed analysis, only 1% teach all topics. CDs need curricula on care delivery topics (cost-effective approach to acute care, role of family medicine in the health care system, quality/safety, and comorbid substance abuse). Single-question assessments overestimate the percentage of clerkships teaching all of the NCC minimum core. Clerkships need national curricula on care delivery topics and tools to help them find their curricular gaps.

Cross-vendor evaluation of key user-defined clinical decision support capabilities: a scenario-based assessment of certified electronic health records with guidelines for future development.

PubMed

McCoy, Allison B; Wright, Adam; Sittig, Dean F

2015-09-01

Clinical decision support (CDS) is essential for delivery of high-quality, cost-effective, and safe healthcare. The authors sought to evaluate the CDS capabilities across electronic health record (EHR) systems. We evaluated the CDS implementation capabilities of 8 Office of the National Coordinator for Health Information Technology Authorized Certification Body (ONC-ACB)-certified EHRs. Within each EHR, the authors attempted to implement 3 user-defined rules that utilized the various data and logic elements expected of typical EHRs and that represented clinically important evidenced-based care. The rules were: 1) if a patient has amiodarone on his or her active medication list and does not have a thyroid-stimulating hormone (TSH) result recorded in the last 12 months, suggest ordering a TSH; 2) if a patient has a hemoglobin A1c result >7% and does not have diabetes on his or her problem list, suggest adding diabetes to the problem list; and 3) if a patient has coronary artery disease on his or her problem list and does not have aspirin on the active medication list, suggest ordering aspirin. Most evaluated EHRs lacked some CDS capabilities; 5 EHRs were able to implement all 3 rules, and the remaining 3 EHRs were unable to implement any of the rules. One of these did not allow users to customize CDS rules at all. The most frequently found shortcomings included the inability to use laboratory test results in rules, limit rules by time, use advanced Boolean logic, perform actions from the alert interface, and adequately test rules. Significant improvements in the EHR certification and implementation procedures are necessary. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Cable Discharge System for fundamental detonator studies

NASA Technical Reports Server (NTRS)

Peevy, Gregg R.; Barnhart, Steven G.; Brigham, William P.

1994-01-01

Sandia National Laboratories has recently completed the modification and installation of a cable discharge system (CDS) which will be used to study the physics of exploding bridgewire (EBW) detonators and exploding foil initiators (EFI or slapper). Of primary interest are the burst characteristics of these devices when subjected to the constant current pulse delivered by this system. The burst process involves the heating of the bridge material to a conductive plasma and is essential in describing the electrical properties of the bridgewire foil for use in diagnostics or computer models. The CDS described herein is capable of delivering up to an 8000 A pulse of 3 micron duration. Experiments conducted with the CDS to characterize the EBW and EFI burst behavior are also described. In addition, the CDS simultaneous VISAR capability permits updating the EFI electrical Gurney analysis parameters used in our computer simulation codes. Examples of CDS generated data for a typical EFI and EBW detonator are provided.

Mapping European Welfare Models: State of the Art of Strategies for Professional Integration and Reintegration of Persons with Chronic Diseases

PubMed Central

Scaratti, Chiara; Silvaggi, Fabiola; Ávila, Carolina C.; Muñoz-Murillo, Amalia; Stavroussi, Panayiota; Roka, Olga; Burger, Helena; Fheodoroff, Klemens; Tobiasz-Adamczyk, Beata; Gruber, Sonja; Svestkova, Olga; Halvorsen, Rune; Kadyrbaeva, Asel; Ferraina, Sabrina

2018-01-01

Background: Persons with chronic diseases (PwCDs) often experience work-related problems, and innovative actions to improve their participation in the labor market are needed. In the frame of the European (EU) Pathways Project, the aim of the study is to compare existing strategies (policies, systems, and services) for professional (re-)integration of PwCDs and mental health conditions available at both European and national level between different European welfare models: Scandinavian, Continental, Anglo-Saxon, Mediterranean, and “Post-Communist”. Method: The European strategies were identified by an overview of relevant academic and grey literature searched through Medline and internet searches, while national strategies were explored through questionnaires and in-depth interviews with national relevant stakeholders. Results: The mapping of existing strategies revealed that, both at European and national level, PwCDs are often considered as part of the group of “persons with disabilities” and only in this case they can receive employment support. European countries put in place actions to support greater labor market participation, but these differ from country to country. Conclusion: Strategies targeting “persons with disabilities” do not necessarily address all the needs of persons with chronic diseases. Countries should consider the importance of employment for all to achieve smart, sustainable, and inclusive growth. PMID:29673231

Using Computational Modeling to Assess the Impact of Clinical Decision Support on Cancer Screening within Community Health Centers

PubMed Central

Carney, Timothy Jay; Morgan, Geoffrey P.; Jones, Josette; McDaniel, Anna M.; Weaver, Michael; Weiner, Bryan; Haggstrom, David A.

2014-01-01

Our conceptual model demonstrates our goal to investigate the impact of clinical decision support (CDS) utilization on cancer screening improvement strategies in the community health care (CHC) setting. We employed a dual modeling technique using both statistical and computational modeling to evaluate impact. Our statistical model used the Spearman’s Rho test to evaluate the strength of relationship between our proximal outcome measures (CDS utilization) against our distal outcome measure (provider self-reported cancer screening improvement). Our computational model relied on network evolution theory and made use of a tool called Construct-TM to model the use of CDS measured by the rate of organizational learning. We employed the use of previously collected survey data from community health centers Cancer Health Disparities Collaborative (HDCC). Our intent is to demonstrate the added valued gained by using a computational modeling tool in conjunction with a statistical analysis when evaluating the impact a health information technology, in the form of CDS, on health care quality process outcomes such as facility-level screening improvement. Significant simulated disparities in organizational learning over time were observed between community health centers beginning the simulation with high and low clinical decision support capability. PMID:24953241

Using Best Practices to Extract, Organize, and Reuse Embedded Decision Support Content Knowledge Rules from Mature Clinical Systems.

PubMed

DesAutels, Spencer J; Fox, Zachary E; Giuse, Dario A; Williams, Annette M; Kou, Qing-Hua; Weitkamp, Asli; Neal R, Patel; Bettinsoli Giuse, Nunzia

2016-01-01

Clinical decision support (CDS) knowledge, embedded over time in mature medical systems, presents an interesting and complex opportunity for information organization, maintenance, and reuse. To have a holistic view of all decision support requires an in-depth understanding of each clinical system as well as expert knowledge of the latest evidence. This approach to clinical decision support presents an opportunity to unify and externalize the knowledge within rules-based decision support. Driven by an institutional need to prioritize decision support content for migration to new clinical systems, the Center for Knowledge Management and Health Information Technology teams applied their unique expertise to extract content from individual systems, organize it through a single extensible schema, and present it for discovery and reuse through a newly created Clinical Support Knowledge Acquisition and Archival Tool (CS-KAAT). CS-KAAT can build and maintain the underlying knowledge infrastructure needed by clinical systems.

How supportive supervision influences immunization session site practices: a quasi-experimental study in Odisha, India.

PubMed

Panda, Bhuputra; Pati, Sanghamitra; Nallala, Srinivas; Chauhan, Abhimanyu S; Anasuya, Anita; Som, Meena; Zodpey, Sanjay

2015-01-01

Routine immunization (RI) is a key child survival intervention. Ensuring acceptable standards of RI service delivery is critical for optimal outcomes. Accumulated evidences suggest that 'supportive supervision' improves the quality of health care services in general. During 2009-2010, the Government of Odisha and UNICEF jointly piloted this strategy in four districts to improve RI program outcomes. The present study aims to assess the effect of this strategy on improvement of skills and practices at immunization session sites. A quasi-experimental 'post-test only' study design was adopted to compare the opinion and practices of frontline health workers and their supervisors in four intervention districts (IDs) with two control districts (CDs). Altogether, we interviewed 111 supervisor-supervisee (health worker) pairs using semi-structured interview schedules and case vignettes. We also directly observed health workers' practices during immunization sessions at 111 sites. Data were analyzed with SPSS version 16.0. The mean knowledge score of supervisors in CDs was significantly higher than in intervention groups. Variegated responses were obtained on case vignettes. The control group performed better in solving certain hypothetically asked problems, whereas the intervention group scored better in others. Health workers in IDs gave a lower rating to their respective supervisors' knowledge, skill, and frequency of supervision. Logistics and vaccine availability were better in CDs. Notwithstanding other limitations, supportive supervision may not have independent effects on improving the quality of immunization services. Addressing systemic issues, such as the availability of essential logistics, supply chain management, timely indenting, and financial resources, could complement the supportive supervision strategy in improving immunization service delivery.

Evaluation of RxNorm for Medication Clinical Decision Support.

PubMed

Freimuth, Robert R; Wix, Kelly; Zhu, Qian; Siska, Mark; Chute, Christopher G

2014-01-01

We evaluated the potential use of RxNorm to provide standardized representations of generic drug name and route of administration to facilitate management of drug lists for clinical decision support (CDS) rules. We found a clear representation of generic drug name but not route of administration. We identified several issues related to data quality, including erroneous or missing defined relationships, and the use of different concept hierarchies to represent the same drug. More importantly, we found extensive semantic precoordination of orthogonal concepts related to route and dose form, which would complicate the use of RxNorm for drug-based CDS. This study demonstrated that while RxNorm is a valuable resource for the standardization of medications used in clinical practice, additional work is required to enhance the terminology so that it can support expanded use cases, such as managing drug lists for CDS.

Evaluation of RxNorm for Medication Clinical Decision Support

PubMed Central

Freimuth, Robert R.; Wix, Kelly; Zhu, Qian; Siska, Mark; Chute, Christopher G.

2014-01-01

We evaluated the potential use of RxNorm to provide standardized representations of generic drug name and route of administration to facilitate management of drug lists for clinical decision support (CDS) rules. We found a clear representation of generic drug name but not route of administration. We identified several issues related to data quality, including erroneous or missing defined relationships, and the use of different concept hierarchies to represent the same drug. More importantly, we found extensive semantic precoordination of orthogonal concepts related to route and dose form, which would complicate the use of RxNorm for drug-based CDS. This study demonstrated that while RxNorm is a valuable resource for the standardization of medications used in clinical practice, additional work is required to enhance the terminology so that it can support expanded use cases, such as managing drug lists for CDS. PMID:25954360

Complex Dynamic Systems View on Conceptual Change: How a Picture of Students' Intuitive Conceptions Accrue from Dynamically Robust Task Dependent Learning Outcomes

ERIC Educational Resources Information Center

Koponen, Ismo T.; Kokkonen, Tommi; Nousiainen, Maiji

2017-01-01

We discuss here conceptual change and the formation of robust learning outcomes from the viewpoint of complex dynamic systems (CDS). The CDS view considers students' conceptions as context dependent and multifaceted structures which depend on the context of their application. In the CDS view the conceptual patterns (i.e. intuitive conceptions…

Scalable Clinical Decision Support for Individualized Cancer Risk Management | Informatics Technology for Cancer Research (ITCR)

Cancer.gov

We will build a scalable clinical decision support (CDS) platform that helps clinicians and patients select cancer screening strategies that are best suited to each individual. This kind of CDS is important because increased evidence supports personalizing cancer screening decisions according to each individual's unique cancer risks. While a highly desired goal, individualizing screening at a population scale requires the implementation of patient-specific risk assessments for several types of cancer. This is quite challenging in today's overwhelmed primary care environment.

Green preparation of carbon dots with papaya as carbon source for effective fluorescent sensing of Iron (III) and Escherichia coli.

PubMed

Wang, Ning; Wang, Yiting; Guo, Tingting; Yang, Ting; Chen, Mingli; Wang, Jianhua

2016-11-15

A simple one-step hydrothermal green approach was reported for the preparation of carbon dots (CDs) without any further decoration or modification with papaya powder as natural carbon source. In this economical and eco-friendly system, deionized water or 90% ethanol was used as solvent to produce water-soluble or ethanol-soluble CDs, respectively, termed as W-CDs and E-CDs. The quantum yield (QY) for W-CDs was 18.98%, while that for E-CDs was 18.39%. The potentials of the prepared carbon dots toward diverse applications were thoroughly investigated. W-CDs and E-CDs provide promising probes for fluorescence detection of Fe(3+), offering limits of detection of 0.48μmolL(-1) and 0.29μmolL(-1), respectively. W-CDs was further demonstrated to be a promising probe for fluorescence sensing of Escherichia coli O157: H7, along with a limit of detection of 9.5×10(4)cfumL(-1). Meanwhile, both W-CDs and E-CDs exhibit favorable biocompatibility, and demonstrated to be efficient for Hela cell imaging. Copyright © 2016 Elsevier B.V. All rights reserved.

A study on the enhancement of opto-electronic properties of CdS thin films: seed-assisted fabrication

NASA Astrophysics Data System (ADS)

Kumarage, W. G. C.; Wijesundera, R. P.; Seneviratne, V. A.; Jayalath, C. P.; Dassanayake, B. S.

2017-04-01

A novel method of fabricating chemical bath deposited CdS thin films (CBD-CdS) by using electrodeposited CdS (ED-CdS) as a seed layer is reported. The resulting thin, compact, uniform and adherent seed-assisted CdS films (ED/CBD-CdS) show enhanced effective surface area compared to both ED-CdS and CBD-CdS. The phase of these CdS films was determined to be hexagonal. The fabricated ED/CBD-CdS films show higher photoelectrochemical (PEC) cell efficiency than either ED-CdS and CBD-CdS thin films. Carrier concentration and flat band potential values for ED/CBD-CdS systems are also found to be superior compared to both ED-CdS and CBD-CdS systems.

Designing Real-time Decision Support for Trauma Resuscitations

PubMed Central

Yadav, Kabir; Chamberlain, James M.; Lewis, Vicki R.; Abts, Natalie; Chawla, Shawn; Hernandez, Angie; Johnson, Justin; Tuveson, Genevieve; Burd, Randall S.

2016-01-01

Background Use of electronic clinical decision support (eCDS) has been recommended to improve implementation of clinical decision rules. Many eCDS tools, however, are designed and implemented without taking into account the context in which clinical work is performed. Implementation of the pediatric traumatic brain injury (TBI) clinical decision rule at one Level I pediatric emergency department includes an electronic questionnaire triggered when ordering a head computed tomography using computerized physician order entry (CPOE). Providers use this CPOE tool in less than 20% of trauma resuscitation cases. A human factors engineering approach could identify the implementation barriers that are limiting the use of this tool. Objectives The objective was to design a pediatric TBI eCDS tool for trauma resuscitation using a human factors approach. The hypothesis was that clinical experts will rate a usability-enhanced eCDS tool better than the existing CPOE tool for user interface design and suitability for clinical use. Methods This mixed-methods study followed usability evaluation principles. Pediatric emergency physicians were surveyed to identify barriers to using the existing eCDS tool. Using standard trauma resuscitation protocols, a hierarchical task analysis of pediatric TBI evaluation was developed. Five clinical experts, all board-certified pediatric emergency medicine faculty members, then iteratively modified the hierarchical task analysis until reaching consensus. The software team developed a prototype eCDS display using the hierarchical task analysis. Three human factors engineers provided feedback on the prototype through a heuristic evaluation, and the software team refined the eCDS tool using a rapid prototyping process. The eCDS tool then underwent iterative usability evaluations by the five clinical experts using video review of 50 trauma resuscitation cases. A final eCDS tool was created based on their feedback, with content analysis of the evaluations performed to ensure all concerns were identified and addressed. Results Among 26 EPs (76% response rate), the main barriers to using the existing tool were that the information displayed is redundant and does not fit clinical workflow. After the prototype eCDS tool was developed based on the trauma resuscitation hierarchical task analysis, the human factors engineers rated it to be better than the CPOE tool for nine of 10 standard user interface design heuristics on a three-point scale. The eCDS tool was also rated better for clinical use on the same scale, in 84% of 50 expert–video pairs, and was rated equivalent in the remainder. Clinical experts also rated barriers to use of the eCDS tool as being low. Conclusions An eCDS tool for diagnostic imaging designed using human factors engineering methods has improved perceived usability among pediatric emergency physicians. PMID:26300010

Phylogenomic Resolution of the Phylogeny of Laurasiatherian Mammals: Exploring Phylogenetic Signals within Coding and Noncoding Sequences.

PubMed

Chen, Meng-Yun; Liang, Dan; Zhang, Peng

2017-08-01

The interordinal relationships of Laurasiatherian mammals are currently one of the most controversial questions in mammalian phylogenetics. Previous studies mainly relied on coding sequences (CDS) and seldom used noncoding sequences. Here, by data mining public genome data, we compiled an intron data set of 3,638 genes (all introns from a protein-coding gene are considered as a gene) (19,055,073 bp) and a CDS data set of 10,259 genes (20,994,285 bp), covering all major lineages of Laurasiatheria (except Pholidota). We found that the intron data contained stronger and more congruent phylogenetic signals than the CDS data. In agreement with this observation, concatenation and species-tree analyses of the intron data set yielded well-resolved and identical phylogenies, whereas the CDS data set produced weakly supported and incongruent results. Further analyses showed that the phylogeny inferred from the intron data is highly robust to data subsampling and change in outgroup, but the CDS data produced unstable results under the same conditions. Interestingly, gene tree statistical results showed that the most frequently observed gene tree topologies for the CDS and intron data are identical, suggesting that the major phylogenetic signal within the CDS data is actually congruent with that within the intron data. Our final result of Laurasiatheria phylogeny is (Eulipotyphla,((Chiroptera, Perissodactyla),(Carnivora, Cetartiodactyla))), favoring a close relationship between Chiroptera and Perissodactyla. Our study 1) provides a well-supported phylogenetic framework for Laurasiatheria, representing a step towards ending the long-standing "hard" polytomy and 2) argues that intron within genome data is a promising data resource for resolving rapid radiation events across the tree of life. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Structural Dynamics of Carbon Dots in Water and N, N-Dimethylformamide Probed by All-Atom Molecular Dynamics Simulations.

PubMed

Paloncýová, Markéta; Langer, Michal; Otyepka, Michal

2018-04-10

Carbon dots (CDs), one of the youngest members of the carbon nanostructure family, are now widely experimentally studied for their tunable fluorescence properties, bleaching resistance, and biocompatibility. Their interaction with biomolecular systems has also been explored experimentally. However, many atomistic details still remain unresolved. Molecular dynamics (MD) simulations enabling atomistic and femtosecond resolutions simultaneously are a well-established tool of computational chemistry which can provide useful insights into investigated systems. Here we present a full procedure for performing MD simulations of CDs. We developed a builder for generating CDs of a desired size and with various oxygen-containing surface functional groups. Further, we analyzed the behavior of various CDs differing in size, surface functional groups, and degrees of functionalization by MD simulations. These simulations showed that surface functionalized CDs are stable in a water environment through the formation of an extensive hydrogen bonding network. We also analyzed the internal dynamics of individual layers of CDs and evaluated the role of surface functional groups on CD stability. We observed that carboxyl groups interconnected the neighboring layers and decreased the rate of internal rotations. Further, we monitored changes in the CD shape caused by an excess of charged carboxyl groups or carbonyl groups. In addition to simulations in water, we analyzed the behavior of CDs in the organic solvent DMF, which decreased the stability of pure CDs but increased the level of interlayer hydrogen bonding. We believe that the developed protocol, builder, and parameters will facilitate future studies addressing various aspects of structural features of CDs and nanocomposites containing CDs.

A survey of intelligent tutoring systems: Implications for complex dynamic systems

NASA Technical Reports Server (NTRS)

Chu, Rose W.

1989-01-01

An overview of the research in the field of intelligent tutorial systems (ITS) is provided. The various approaches in the design and implementation of ITS are examined and discussed in the context of problem solving in an environment of a complex dynamic system (CDS). Issues pertaining to a CDS and the nature of human problem solving especially in light of a CDS are considered. An overview of the architecture of an ITS is provided as the basis for the in-depth examination of various systems. Finally, the implications for the design and evaluation of an ITS are discussed.

Chemical Sensors Based on Cyclodextrin Derivatives.

PubMed

Ogoshi, Tomoki; Harada, Akira

2008-08-25

This review focuses on chemical sensors based on cyclodextrin (CD) derivatives. This has been a field of classical interest, and is now of current interest for numerous scientists. First, typical chemical sensors using chromophore appended CDs are mentioned. Various "turn-off" and "turn-on" fluorescent chemical sensors, in which fluorescence intensity was decreased or increased by complexation with guest molecules, respectively, were synthesized. Dye modified CDs and photoactive metal ion-ligand complex appended CDs, metallocyclodextrins, were also applied for chemical sensors. Furthermore, recent novel approaches to chemical sensing systems using supramolecular structures such as CD dimers, trimers and cooperative binding systems of CDs with the other macrocycle [2]rotaxane and supramolecular polymers consisting of CD units are mentioned. New chemical sensors using hybrids of CDs with p-conjugated polymers, peptides, DNA, nanocarbons and nanoparticles are also described in this review.

In Situ Localized Surface Plasmon Resonance (LSPR) Spectroscopy to Investigate Kinetics of Chemical Bath Deposition of CdS Thin Films

DOE PAGES

Kalyanaraman, Ramki; Taz, Humaira; Ruther, Rose E.; ...

2015-02-11

Techniques that can characterize the early stages of thin film deposition from liquid phase processes can aid greatly in our understanding of mechanistic aspects of chemical bath deposition (CBD). Here we have used localized surface plasmon resonance (LSPR) spectroscopy to monitor in-situ the kinetics of early-stage growth of cadmium sulfide (CdS) thin films on Ag nanoparticle on quartz substrates. Real-time shift during CdS deposition showed that the LSPR wavelength red shifted rapidly due to random deposition of CdS on the substrate, but saturated at longer times. LSPR modeling showed that these features could be interpreted as an initial deposition ofmore » CdS islands followed by preferential deposition onto itself. The CdS also showed significantly enhanced Raman signals up to 170 times due to surface enhanced raman scattering (SERS) from the CdS/Ag NP regions. The ex-situ SERS effect supported the LSPR shift suggesting that these techniques could be used to understand nucleation and growth phenomena from the liquid phase.« less

Development and use of active clinical decision support for preemptive pharmacogenomics

PubMed Central

Bell, Gillian C; Crews, Kristine R; Wilkinson, Mark R; Haidar, Cyrine E; Hicks, J Kevin; Baker, Donald K; Kornegay, Nancy M; Yang, Wenjian; Cross, Shane J; Howard, Scott C; Freimuth, Robert R; Evans, William E; Broeckel, Ulrich; Relling, Mary V; Hoffman, James M

2014-01-01

Background Active clinical decision support (CDS) delivered through an electronic health record (EHR) facilitates gene-based drug prescribing and other applications of genomics to patient care. Objective We describe the development, implementation, and evaluation of active CDS for multiple pharmacogenetic test results reported preemptively. Materials and methods Clinical pharmacogenetic test results accompanied by clinical interpretations are placed into the patient's EHR, typically before a relevant drug is prescribed. Problem list entries created for high-risk phenotypes provide an unambiguous trigger for delivery of post-test alerts to clinicians when high-risk drugs are prescribed. In addition, pre-test alerts are issued if a very-high risk medication is prescribed (eg, a thiopurine), prior to the appropriate pharmacogenetic test result being entered into the EHR. Our CDS can be readily modified to incorporate new genes or high-risk drugs as they emerge. Results Through November 2012, 35 customized pharmacogenetic rules have been implemented, including rules for TPMT with azathioprine, thioguanine, and mercaptopurine, and for CYP2D6 with codeine, tramadol, amitriptyline, fluoxetine, and paroxetine. Between May 2011 and November 2012, the pre-test alerts were electronically issued 1106 times (76 for thiopurines and 1030 for drugs metabolized by CYP2D6), and the post-test alerts were issued 1552 times (1521 for TPMT and 31 for CYP2D6). Analysis of alert outcomes revealed that the interruptive CDS appropriately guided prescribing in 95% of patients for whom they were issued. Conclusions Our experience illustrates the feasibility of developing computational systems that provide clinicians with actionable alerts for gene-based drug prescribing at the point of care. PMID:23978487

Improved blood utilization using real-time clinical decision support.

PubMed

Goodnough, Lawrence T; Shieh, Lisa; Hadhazy, Eric; Cheng, Nathalie; Khari, Paul; Maggio, Paul

2014-05-01

We analyzed blood utilization at Stanford Hospital and Clinics after implementing real-time clinical decision support (CDS) and best practice alerts (BPAs) into physician order entry (POE) for blood transfusions. A clinical effectiveness (CE) team developed consensus with a suggested transfusion threshold of a hemoglobin (Hb) level of 7 g/dL, or 8 g/dL for patients with acute coronary syndromes. The CDS was implemented in July 2010 and consisted of an interruptive BPA at POE, a link to relevant literature, and an "acknowledgment reason" for the blood order. The percentage of blood ordered for patients whose most recent Hb level exceeded 8 g/dL ranged at baseline from 57% to 66%; from the education intervention by the CE team August 2009 to July 2010, the percentage decreased to a range of 52% to 56% (p = 0.01); and after implementation of CDS and BPA, by end of December 2010 the percentage of patients transfused outside the guidelines decreased to 35% (p = 0.02) and has subsequently remained below 30%. For the most recent interval, only 27% (767 of 2890) of transfusions occurred in patients outside guidelines. Comparing 2009 to 2012, despite an increase in annual case mix index from 1.952 to 2.026, total red blood cell (RBC) transfusions decreased by 7186 units, or 24%. The estimated net savings for RBC units (at $225/unit) in purchase costs for 2012 compared to 2009 was $1,616,750. Real-time CDS has significantly improved blood utilization. This system of concurrent review can be used by health care institutions, quality departments, and transfusion services to reduce blood transfusions. © 2013 American Association of Blood Banks.

An amplified chemiluminescence system based on Si-doped carbon dots for detection of catecholamines.

PubMed

Amjadi, Mohammad; Hallaj, Tooba; Manzoori, Jamshid L; Shahbazsaghir, Tahmineh

2018-08-05

We report on a chemiluminescence (CL) system based on simultaneous enhancing effect of Si-doped carbon dots (Si-CDs) and cetyltrimethylammonium bromide (CTAB) on HCO 3 - -H 2 O 2 reaction . The possible CL mechanism is investigated and discussed. Excited-state Si-CDs was found to be the final emitting species, which are probably produced via electron and hole injection by oxy-radicals. The effect of several other heteroatom-doped CDs and undoped CDs was also investigated and compared with Si-CDs. Furthermore, it was found that catecholamines such as dopamine, adrenaline and noradrenaline remarkably diminish the CL intensity of Si-CD-HCO 3 - -H 2 O 2 -CTAB system. By taking advantage of this fact, a sensitive probe was designed for determination of dopamine, adrenaline and noradrenaline with a limit of detection of 0.07, 0.60 and 0.01 μM, respectively. The method was applied to the determination of catecholamines in human plasma samples. Copyright © 2018 Elsevier B.V. All rights reserved.

Negative surface streamers propagating on TiO2 and γ-Al2O3-supported Ag catalysts: ICCD imaging and modeling study

NASA Astrophysics Data System (ADS)

Kim, Hyun-Ha; Teramoto, Yoshiyuki; Ogata, Atsushi; Kang, Woo Seok; Hur, Min; Song, Young-Hoon

2018-06-01

Surface streamers propagating on the surface of titanium dioxide (TiO2) and alumina (γ-Al2O3) were studied in negative polarity using intensified charge coupled device (ICCD) imaging and numerical simulation. Detailed time-resolved ICCD images of cathode-directed streamers (CDSs) emanating from a ground electrode are first presented in this report. Instead of primary streamers in positive polarity, only a glow-like discharge appeared in the early stage at the cathode under negative polarity. After this discharge disappeared, a counter-propagating CDS initiated from the ground electrode (anode). Numerical simulation indicated that strong electric fields at the pellet-anode and the formation of positive ion rich local spots were the main reason for the CDS formation near the ground electrode. The maximum velocity was 750 km s‑1 for Ag-supported γ-Al2O3 and 550 km s‑1 for Ag-supported TiO2, respectively. In contrast to the CDS in the gas-phase with a positive polarity, the CDS in a catalyst packed-bed under negative polarity showed more branching and a larger number of streamers in the presence of oxygen than in pure N2.

Automated acute kidney injury alerts.

PubMed

Kashani, Kianoush B

2018-05-02

Acute kidney injury (AKI) is one of the most common and probably one of the more consequential complications of critical illnesses. Recent information indicates that it is at least partially preventable; however, progress in its prevention, management, and treatment has been hindered by the scarcity of knowledge for effective interventions, inconsistencies in clinical practices, late identification of patients at risk for or with AKI, and limitations of access to best practices for prevention and management of AKI. Growing use of electronic health records has provided a platform for computer science to engage in data mining and processing, not only for early detection of AKI but also for the development of risk-stratification strategies and computer clinical decision-support (CDS) systems. Despite promising perspectives, the literature regarding the impact of AKI electronic alerts and CDS systems has been conflicting. Some studies have reported improvement in care processes and patient outcomes, whereas others have shown no effect on clinical outcomes and yet demonstrated an increase in the use of resources. These discrepancies are thought to be due to multiple factors that may be related to technology, human factors, modes of delivery of information to clinical providers, and level of expectations regarding the impact on patient outcomes. This review appraises the current body of knowledge and provides some outlines regarding research into and clinical aspects of CDS systems for AKI. Copyright © 2018 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Improved Dynamic Modeling of the Cascade Distillation Subsystem and Analysis of Factors Affecting Its Performance

NASA Technical Reports Server (NTRS)

Perry, Bruce A.; Anderson, Molly S.

2015-01-01

The Cascade Distillation Subsystem (CDS) is a rotary multistage distiller being developed to serve as the primary processor for wastewater recovery during long-duration space missions. The CDS could be integrated with a system similar to the International Space Station Water Processor Assembly to form a complete water recovery system for future missions. A preliminary chemical process simulation was previously developed using Aspen Custom Modeler® (ACM), but it could not simulate thermal startup and lacked detailed analysis of several key internal processes, including heat transfer between stages. This paper describes modifications to the ACM simulation of the CDS that improve its capabilities and the accuracy of its predictions. Notably, the modified version can be used to model thermal startup and predicts the total energy consumption of the CDS. The simulation has been validated for both NaC1 solution and pretreated urine feeds and no longer requires retuning when operating parameters change. The simulation was also used to predict how internal processes and operating conditions of the CDS affect its performance. In particular, it is shown that the coefficient of performance of the thermoelectric heat pump used to provide heating and cooling for the CDS is the largest factor in determining CDS efficiency. Intrastage heat transfer affects CDS performance indirectly through effects on the coefficient of performance.

Easy Preparation and Photoelectrochemical Properties of CdS Nanoparticle/Graphene Nanosheet Nanocomposites Using Supercritical Carbon Dioxide.

PubMed

Yan, Shancheng; Xu, Xin; Jiang, Chao; Pan, Lijia; Shi, Yi; Hu, Dong; Cao, Zhenglin

2016-03-01

Graphene nanosheets (GNSs) were modified with CdS nanoparticles (NPs) using supercritical CO2 (SC CO2), which has gas-like diffusivity, low viscosity, and near-zero surface tension. The resulting CdS NP/GNS nanocomposites were characterized by field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, and photoluminescence spectroscopy. Distinct morphologies of CdS NP/GNS nanocomposites decorated on the GNS surface were obtained at different SC CO2 pressures, temperatures, and durations and in different sources. Results showed that the sources and SC CO2 significantly influenced the aggregation or assembly behavior of the CdS NP/GNS nanocomposites on the GNSs. The formation mechanism of the distinct nanohybrid structures was studied by Raman mapping. A difference was noted between the Raman spectra of pristine graphene nanosheets and CdS NP/GNS nanocomposites. This result can be ascribed to the CdS NPs anchored onto the GNS defects and to the improved quality of the GNSs under SC CO2. The photo-current densities of CdS NP/GNS nanocomposites were at least three times higher than that of the pristine CdS NPs at the same applied voltage for photoelectrochemical water splitting. The findings suggested that highly efficient graphene-supported NP photoelectrocatalysts can be fabricated by the supercritical fluid method and that graphene can serve as a favorable photoelectrocatalytic carrier, with promising potential applications in environmental and energy fields. Keywords: Graphene Nanosheets, Cadmium Sulfide, Raman Spectroscopy, Photoelectrochemical.

Optical characterization of CdS nanoparticles embedded into the comb-type amphiphilic graft copolymer

NASA Astrophysics Data System (ADS)

Kalaycı, Özlem A.; Duygulu, Özgür; Hazer, Baki

2013-01-01

This study refers to the synthesis and characterization of a novel organic/inorganic hybrid nanocomposite material containing cadmium sulfide (CdS) nanoparticles. For this purpose, a series of polypropylene (PP)-g-polyethylene glycol (PEG), PP-g-PEG comb-type amphiphilic graft copolymers were synthesized. PEGs with Mn = 400, 2000, 3350, and 8000 Da were used and the graft copolymers obtained were coded as PPEG400, PPEG2000, PPEG3350, and PPEG8000. CdS nanoparticles were formed in tetrahydrofuran solution of PP-g-PEG amphiphilic comb-type copolymer by the reaction between aqueous solutions of Na2S and Cd(CH3COO)2 simultaneously. Micelle formation of PPEG2000 comb-type amphiphilic graft copolymer in both solvent/non-solvent (petroleum ether-THF) by transmission electron microscopy (TEM). The optical characteristics, size morphology, phase analysis, and dispersion of CdS nanoparticles embedded in PPEG400, PPEG2000, PPEG3350, and PPEG8000 comb-type amphiphilic graft copolymer micelles were determined by high resolution TEM (HRTEM), energy dispersive spectroscopy, UV-vis spectroscopy, and fluorescence emission spectroscopy techniques. The aggregate size of PPEG2000-CdS is between 10 and 50 nm; however, in the case of PPEG400-CdS, PPEG3350-CdS, and PPEG8000-CdS samples, it is up to approximately 100 nm. The size of CdS quantum dots in the aggregates for PPEG2000 and PPEG8000 samples was observed as 5 nm by HRTEM analysis, and this result was also supported by UV-vis absorbance spectra and fluorescence emission spectra.

Mapping European Welfare Models: State of the Art of Strategies for Professional Integration and Reintegration of Persons with Chronic Diseases.

PubMed

Scaratti, Chiara; Leonardi, Matilde; Silvaggi, Fabiola; Ávila, Carolina C; Muñoz-Murillo, Amalia; Stavroussi, Panayiota; Roka, Olga; Burger, Helena; Fheodoroff, Klemens; Tobiasz-Adamczyk, Beata; Sabariego, Carla; Esteban, Eva; Gruber, Sonja; Svestkova, Olga; Halvorsen, Rune; Kadyrbaeva, Asel; Ferraina, Sabrina

2018-04-17

Background: Persons with chronic diseases (PwCDs) often experience work-related problems, and innovative actions to improve their participation in the labor market are needed. In the frame of the European (EU) Pathways Project, the aim of the study is to compare existing strategies (policies, systems, and services) for professional (re-)integration of PwCDs and mental health conditions available at both European and national level between different European welfare models: Scandinavian, Continental, Anglo-Saxon, Mediterranean, and “Post-Communist”. Method : The European strategies were identified by an overview of relevant academic and grey literature searched through Medline and internet searches, while national strategies were explored through questionnaires and in-depth interviews with national relevant stakeholders. Results : The mapping of existing strategies revealed that, both at European and national level, PwCDs are often considered as part of the group of “persons with disabilities” and only in this case they can receive employment support. European countries put in place actions to support greater labor market participation, but these differ from country to country. Conclusion : Strategies targeting “persons with disabilities” do not necessarily address all the needs of persons with chronic diseases. Countries should consider the importance of employment for all to achieve smart, sustainable, and inclusive growth.

Carbon Dots as Versatile Photosensitizers for Solar-Driven Catalysis with Redox Enzymes.

PubMed

Hutton, Georgina A M; Reuillard, Bertrand; Martindale, Benjamin C M; Caputo, Christine A; Lockwood, Colin W J; Butt, Julea N; Reisner, Erwin

2016-12-28

Light-driven enzymatic catalysis is enabled by the productive coupling of a protein to a photosensitizer. Photosensitizers used in such hybrid systems are typically costly, toxic, and/or fragile, with limited chemical versatility. Carbon dots (CDs) are low-cost, nanosized light-harvesters that are attractive photosensitizers for biological systems as they are water-soluble, photostable, nontoxic, and their surface chemistry can be easily modified. We demonstrate here that CDs act as excellent light-absorbers in two semibiological photosynthetic systems utilizing either a fumarate reductase (FccA) for the solar-driven hydrogenation of fumarate to succinate or a hydrogenase (H 2 ase) for reduction of protons to H 2 . The tunable surface chemistry of the CDs was exploited to synthesize positively charged ammonium-terminated CDs (CD-NHMe 2 + ), which were capable of transferring photoexcited electrons directly to the negatively charged enzymes with high efficiency and stability. Enzyme-based turnover numbers of 6000 mol succinate (mol FccA) -1 and 43,000 mol H 2 (mol H 2 ase) -1 were reached after 24 h. Negatively charged carboxylate-terminated CDs (CD-CO 2 - ) displayed little or no activity, and the electrostatic interactions at the CD-enzyme interface were determined to be essential to the high photocatalytic activity observed with CD-NHMe 2 + . The modular surface chemistry of CDs together with their photostability and aqueous solubility make CDs versatile photosensitizers for redox enzymes with great scope for their utilization in photobiocatalysis.

Improved Dynamic Modeling of the Cascade Distillation Subsystem and Integration with Models of Other Water Recovery Subsystems

NASA Technical Reports Server (NTRS)

Perry, Bruce; Anderson, Molly

2015-01-01

The Cascade Distillation Subsystem (CDS) is a rotary multistage distiller being developed to serve as the primary processor for wastewater recovery during long-duration space missions. The CDS could be integrated with a system similar to the International Space Station (ISS) Water Processor Assembly (WPA) to form a complete Water Recovery System (WRS) for future missions. Independent chemical process simulations with varying levels of detail have previously been developed using Aspen Custom Modeler (ACM) to aid in the analysis of the CDS and several WPA components. The existing CDS simulation could not model behavior during thermal startup and lacked detailed analysis of several key internal processes, including heat transfer between stages. The first part of this paper describes modifications to the ACM model of the CDS that improve its capabilities and the accuracy of its predictions. Notably, the modified version of the model can accurately predict behavior during thermal startup for both NaCl solution and pretreated urine feeds. The model is used to predict how changing operating parameters and design features of the CDS affects its performance, and conclusions from these predictions are discussed. The second part of this paper describes the integration of the modified CDS model and the existing WPA component models into a single WRS model. The integrated model is used to demonstrate the effects that changes to one component can have on the dynamic behavior of the system as a whole.

Construction of an all-solid-state artificial Z-scheme system consisting of Bi2WO6/Au/CdS nanostructure for photocatalytic CO2 reduction into renewable hydrocarbon fuel.

PubMed

Wang, Meng; Han, Qiutong; Li, Liang; Tang, Lanqin; Li, Haijin; Zhou, Yong; Zou, Zhigang

2017-07-07

An all-solid-state Bi 2 WO 6 /Au/CdS Z-scheme system was constructed for the photocatalytic reduction of CO 2 into methane in the presence of water vapor. This Z-scheme consists of ultrathin Bi 2 WO 6 nanoplates and CdS nanoparticles as photocatalysts, and a Au nanoparticle as a solid electron mediator offering a high speed charge transfer channel and leading to more efficient spatial separation of electron-hole pairs. The photo-generated electrons from the conduction band (CB) of Bi 2 WO 6 transfer to the Au, and then release to the valence band (VB) of CdS to recombine with the holes of CdS. It allows the electrons remaining in the CB of CdS and holes in the VB of Bi 2 WO 6 to possess strong reduction and oxidation powers, respectively, leading the Bi 2 WO 6 /Au/CdS to exhibit high photocatalytic reduction of CO 2 , relative to bare Bi 2 WO 6 , Bi 2 WO 6 /Au, and Bi 2 WO 6 /CdS. The depressed hole density on CdS also enhances the stability of the CdS against photocorrosion.

Using Best Practices to Extract, Organize, and Reuse Embedded Decision Support Content Knowledge Rules from Mature Clinical Systems

PubMed Central

DesAutels, Spencer J.; Fox, Zachary E.; Giuse, Dario A.; Williams, Annette M.; Kou, Qing-hua; Weitkamp, Asli; Neal R, Patel; Bettinsoli Giuse, Nunzia

2016-01-01

Clinical decision support (CDS) knowledge, embedded over time in mature medical systems, presents an interesting and complex opportunity for information organization, maintenance, and reuse. To have a holistic view of all decision support requires an in-depth understanding of each clinical system as well as expert knowledge of the latest evidence. This approach to clinical decision support presents an opportunity to unify and externalize the knowledge within rules-based decision support. Driven by an institutional need to prioritize decision support content for migration to new clinical systems, the Center for Knowledge Management and Health Information Technology teams applied their unique expertise to extract content from individual systems, organize it through a single extensible schema, and present it for discovery and reuse through a newly created Clinical Support Knowledge Acquisition and Archival Tool (CS-KAAT). CS-KAAT can build and maintain the underlying knowledge infrastructure needed by clinical systems. PMID:28269846

Facile synthesis of silver nanoparticles/carbon dots for a charge transfer study and peroxidase-like catalytic monitoring by surface-enhanced Raman scattering

NASA Astrophysics Data System (ADS)

Zhao, Hongyue; Guo, Yue; Zhu, Shoujun; Song, Yubin; Jin, Jing; Ji, Wei; Song, Wei; Zhao, Bing; Yang, Bai; Ozaki, Yukihiro

2017-07-01

In this work, carbon dots (CDs) were combined with Ag nanoparticles (NPs) by a chemical reaction to form Ag NPs/CDs hybrid, which was then used as a novel surface-enhanced Raman scattering (SERS) substrate. During the synthetic process, carboxyl groups on the surface of Ag NPs were reacted with amino groups of CDs in an amidation reaction. The D and G bands of CDs in the Ag NPs/CDs hybrid could be easily detected by SERS. By employing p-aminothiophenol (PATP) molecules as SERS probes, the Ag NPs/CDs hybrid substrate could detect PATP in diluted solutions of concentration as low as 10-9 M. The charge transfer (CT) effect on SERS spectra with different excitation wavelengths in the prepared Ag NPs/CDs hybrid and PATP system was also investigated. It was found that addition of CDs changes the degree of CT between Ag NPs and PATP molecules. Since the prepared Ag NPs/CDs hybrid also showed a peroxidase-like activity toward the oxidation of 3,3‧,5,5‧-tetramethylbenzidine using H2O2, which can provide the sensitive detection of H2O2 by SERS technique.

Increasing Complexity in Rule-Based Clinical Decision Support: The Symptom Assessment and Management Intervention.

PubMed

Lobach, David F; Johns, Ellis B; Halpenny, Barbara; Saunders, Toni-Ann; Brzozowski, Jane; Del Fiol, Guilherme; Berry, Donna L; Braun, Ilana M; Finn, Kathleen; Wolfe, Joanne; Abrahm, Janet L; Cooley, Mary E

2016-11-08

Management of uncontrolled symptoms is an important component of quality cancer care. Clinical guidelines are available for optimal symptom management, but are not often integrated into the front lines of care. The use of clinical decision support (CDS) at the point-of-care is an innovative way to incorporate guideline-based symptom management into routine cancer care. The objective of this study was to develop and evaluate a rule-based CDS system to enable management of multiple symptoms in lung cancer patients at the point-of-care. This study was conducted in three phases involving a formative evaluation, a system evaluation, and a contextual evaluation of clinical use. In Phase 1, we conducted iterative usability testing of user interface prototypes with patients and health care providers (HCPs) in two thoracic oncology clinics. In Phase 2, we programmed complex algorithms derived from clinical practice guidelines into a rules engine that used Web services to communicate with the end-user application. Unit testing of algorithms was conducted using a stack-traversal tree-spanning methodology to identify all possible permutations of pathways through each algorithm, to validate accuracy. In Phase 3, we evaluated clinical use of the system among patients and HCPs in the two clinics via observations, structured interviews, and questionnaires. In Phase 1, 13 patients and 5 HCPs engaged in two rounds of formative testing, and suggested improvements leading to revisions until overall usability scores met a priori benchmarks. In Phase 2, symptom management algorithms contained between 29 and 1425 decision nodes, resulting in 19 to 3194 unique pathways per algorithm. Unit testing required 240 person-hours, and integration testing required 40 person-hours. In Phase 3, both patients and HCPs found the system usable and acceptable, and offered suggestions for improvements. A rule-based CDS system for complex symptom management was systematically developed and tested. The complexity of the algorithms required extensive development and innovative testing. The Web service-based approach allowed remote access to CDS knowledge, and could enable scaling and sharing of this knowledge to accelerate availability, and reduce duplication of effort. Patients and HCPs found the system to be usable and useful. ©David F Lobach, Ellis B Johns, Barbara Halpenny, Toni-Ann Saunders, Jane Brzozowski, Guilherme Del Fiol, Donna L Berry, Ilana M Braun, Kathleen Finn, Joanne Wolfe, Janet L Abrahm, Mary E Cooley. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 08.11.2016.

[Properties of synthesized CdS nanoparticles by reverse micelle method].

PubMed

Li, Heng-Da; Wang, Qing-Wei; Zhai, Hong-Ju; Li, Wen-Lian

2008-07-01

Micelle system with reverse phase (water/CTAB/n-hexyl alcohol/n-heptane) is a weenie liquid-globelet of surface active agent molecule which can be stably and uniformly dispersed in continuous oil medium. The micelle system with reverse phase can work as a "micro-reactor" to synthesize CdS nano-particle with excellent performance. In the present article considering the effects of W value (W= [water]/[surface agent]) of the micelle system with reverse phase, we observed that the ratio of [Cd2+] and [S2-] ions to the original concentrations of the Cd2+ and S2- ions can affect the luminescent properties of CdS nano-particle. Using regurgitant treatment process the surface of CdS nano-particle can be modified, and as a result the defect emission was reduced and even disappeared, but exciton emissions markedly increased. On the other hand, a red-shift of the exciton emission peak with the increase in the particle size was observed, indicating considerable quantum confinement effect. A maximum quantum efficiency of 11% for the synthesized CdS nano-material was achieved.

Preparation, characterization and in vivo evaluation of a combination delivery system based on hyaluronic acid/jeffamine hydrogel loaded with PHBV/PLGA blend nanoparticles for prolonged delivery of Teriparatide.

PubMed

Bahari Javan, Nika; Montazeri, Hamed; Rezaie Shirmard, Leila; Jafary Omid, Nersi; Barbari, Ghullam Reza; Amini, Mohsen; Ghahremani, Mohammad Hossein; Rafiee-Tehrani, Morteza; Abedin Dorkoosh, Farid

2017-04-01

In the current study, biodegradable PHBV/PLGA blend nanoparticles (NPs) containing Teriparatide were loaded in hyaluronic acid/jeffamine (HA-JEF ED-600) hydrogel to prepare a combination delivery system (CDS) for prolonged delivery of Teriparatide. The principal purpose of the present study was to formulate an effective and prolonged Teriparatide delivery system in order to reduce the frequency of injection and thus enhance patient's compliance. Morphological properties, swelling behaviour, crosslinking efficiency and rheological characterization of HA-JEF ED-600 hydrogel were evaluated. The CDS was acquired by adding PHBV/PLGA NPs to HA-JEF ED-600 hydrogel simultaneously with crosslinking reaction. The percentage of NPs incorporation within the hydrogel as well as the loading capacity and morphology of Teriparatide loaded CDS were examined. Intrinsic fluorescence and circular dichroism spectroscopy proved that Teriparatide remains stable after processing. The release profile represented 63% Teriparatide release from CDS within 50days with lower burst release compared to NPs and hydrogel. MTT assay was conducted by using NIH3T3 cell line and no sign of reduction in cell viability was observed. Based on Miller and Tainter method, LD 50 of Teriparatide loaded CDS was 131.8mg/kg. In vivo studies demonstrated that Teriparatide loaded CDS could effectively increase serum calcium level after subcutaneous injection in mice. Favourable results in the current study introduced CDS as a promising candidate for controlled delivery of Teriparatide and pave the way for future investigations in the field of designing prolonged delivery systems for other peptides and proteins. Copyright © 2017 Elsevier B.V. All rights reserved.

Retrospective checking of compliance with practice guidelines for acute stroke care: a novel experiment using openEHR’s Guideline Definition Language

PubMed Central

2014-01-01

Background Providing scalable clinical decision support (CDS) across institutions that use different electronic health record (EHR) systems has been a challenge for medical informatics researchers. The lack of commonly shared EHR models and terminology bindings has been recognised as a major barrier to sharing CDS content among different organisations. The openEHR Guideline Definition Language (GDL) expresses CDS content based on openEHR archetypes and can support any clinical terminologies or natural languages. Our aim was to explore in an experimental setting the practicability of GDL and its underlying archetype formalism. A further aim was to report on the artefacts produced by this new technological approach in this particular experiment. We modelled and automatically executed compliance checking rules from clinical practice guidelines for acute stroke care. Methods We extracted rules from the European clinical practice guidelines as well as from treatment contraindications for acute stroke care and represented them using GDL. Then we executed the rules retrospectively on 49 mock patient cases to check the cases’ compliance with the guidelines, and manually validated the execution results. We used openEHR archetypes, GDL rules, the openEHR reference information model, reference terminologies and the Data Archetype Definition Language. We utilised the open-sourced GDL Editor for authoring GDL rules, the international archetype repository for reusing archetypes, the open-sourced Ocean Archetype Editor for authoring or modifying archetypes and the CDS Workbench for executing GDL rules on patient data. Results We successfully represented clinical rules about 14 out of 19 contraindications for thrombolysis and other aspects of acute stroke care with 80 GDL rules. These rules are based on 14 reused international archetypes (one of which was modified), 2 newly created archetypes and 51 terminology bindings (to three terminologies). Our manual compliance checks for 49 mock patients were a complete match versus the automated compliance results. Conclusions Shareable guideline knowledge for use in automated retrospective checking of guideline compliance may be achievable using GDL. Whether the same GDL rules can be used for at-the-point-of-care CDS remains unknown. PMID:24886468

The Learning Management System Evolution. CDS Spotlight Report. Research Bulletin

ERIC Educational Resources Information Center

Lang, Leah; Pirani, Judith A.

2014-01-01

This Spotlight focuses on data from the 2013 Core Data Service (CDS) to better understand how higher education institutions approach learning management systems (LMSs). Information provided for this Spotlight was derived from Module 8 of the Core Data Service, which contains several questions regarding information systems and applications.…

The Impact of Electronic Knowledge-Based Nursing Content and Decision-Support on Nursing-Sensitive Patient Outcomes

DTIC Science & Technology

2014-02-01

aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information...if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE February 2014 2... Akre , et al., 2006) content and evidence-based clinical decision support (CDS) tools were embedded into the EHR of one large health care system. Since

Collaboration, campaigns and champions for appropriate imaging: feedback from the Zagreb workshop.

PubMed

Remedios, D; Brkljacic, B; Ebdon-Jackson, S; Hierath, M; Sinitsyn, V; Vassileva, J

2018-04-01

Leading radiologists and representatives from national radiation protection regulatory authorities and health ministries from 19 countries of the European region worked together with five experts at the workshop on justification and appropriate use of imaging in Zagreb, Croatia, from 26 to 28 October 2017 jointly organised by the IAEA and the European Society of Radiology. The workshop served as a forum to exchange information on challenges and solutions for improving justification and the appropriate use of diagnostic imaging. Common barriers to improving the use of imaging referral guidelines were discussed and the need for increased collaboration identified. Examples of good practices were presented, including use of Clinical Decision Support (CDS) systems to facilitate rapid and good justification decisions. The workshop identified some of the needs of European countries for achieving more appropriate imaging proposing wider use of collaboration, campaigns and champions. • Drivers for appropriate imaging in Europe are similar to those elsewhere globally. • Implementing imaging referral guidelines is the main barrier to more appropriate imaging. • Clinical Decision Support systems (CDS) facilitates good referral practice and justification decisions. • Collaboration, campaigns and champions may improve awareness, appropriateness and audit.

Exciton-Plasmon Interaction between AuNPs/Graphene Nanohybrids and CdS Quantum Dots/TiO2 for Photoelectrochemical Aptasensing of Prostate-Specific Antigen.

PubMed

Cai, Guoneng; Yu, Zhengzhong; Ren, Rongrong; Tang, Dianping

2018-03-23

A competitive-displacement reaction strategy based on target-induced dissociation of gold nanoparticle coated graphene nanosheet (AuNPs/GN) from CdS quantum dot functionalized mesoporous titanium dioxide (CdS QDs/TiO 2 ) was designed for the sensitive photoelectrochemical (PEC) aptasensing of prostate-specific antigen (PSA) through the exciton-plasmon interaction (EPI) between CdS QDs and AuNPs. To construct such an aptasensing system, capture DNA was initially conjugated covalently onto CdS QDs/TiO 2 -modified electrode, and then AuNPs/GN-labeled PSA aptamer was bound onto biofunctionalized CdS QDs/TiO 2 via hybridization chain reaction of partial bases with capture DNA. Introduction of AuNPs/GN efficiently quenched the photocurrent of CdS QDs/TiO 2 thanks to energy transfer. Upon addition of target PSA, the sandwiched aptamer between CdS QDs/TiO 2 and AuNPs/GN reacted with the analyte analyte, thus resulting in the dissociation of AuNPs/GN from the CdS QDs/TiO 2 to increase the photocurrent. Under optimum conditions, the aptasensing platform exhibited a high sensitivity for PSA detection within a dynamic linear range of 1.0 pg/mL to 8.0 ng/mL at a low limitat of detection of 0.52 pg/mL. The interparticle distance of exciton-plasmon interaction and contents of AuNPs corresponding to EPI effect in this system were also studied. Good selectivity and high reproducibility were obtained for the analysis of target PSA. Importantly, the accuracy and matrix effect of PEC aptasensor was evaluated for the determination of human serum specimens and newborn calf serum-diluted PSA standards, giving a well-matched result with the referenced PSA ELISA kit.

Distribution of different surface modified carbon dots in pumpkin seedlings.

PubMed

Qian, Kun; Guo, Huiyuan; Chen, Guangcai; Ma, Chuanxin; Xing, Baoshan

2018-05-22

The distribution of surface modified carbon dots (CDs) in the pumpkin seedlings was studied by visualization techniques and their potential phytotoxicity was investigated at both the physiological and biochemical levels. The average size of carbon dots was approximately 4 nm. The fluorescent peaks of bared CDs, CD-PEI and CD-PAA were between 420 nm and 500 nm, indicating CDs could emit blue and green fluorescence. Fluorescent images showed that all three types of CDs could accumulate in the pumpkin roots and translocate to the shoots, although the distribution pattern of each CDs was obviously different. At the biochemical level, the elevated antioxidant enzymes in pumpkin roots suggest that all the CDs could potentially trigger the antioxidant defense systems in pumpkin seedlings. Additionally, such alteration was greater in the roots than in the shoots. Our study represents a new perspective on CD visualization in plant tissues and provide useful information for the potential toxicity of different types of CDs to terrestrial plants, which is of importance to agricultural application.

Development of the command data system and ground software for the SEDSAT-1 microsatellite

NASA Technical Reports Server (NTRS)

Wells, B. Earl

1996-01-01

SEDSAT-1 is designed to be a low cost scientific satellite which is to be used to perform a minimum of five tasks which include: (1) the acquisition of a number of important parameters associated with the tethering processes from the payloads perspective (such as accelerations incurred and imaging data of the tether during deployment), (2) to act as a remote sensing platform for making measurements of the Earth's Atmosphere (allowing research to be performed in such areas as vertical lightning observation, visible light spectrography, and cloud cover studies, (3) to act as a general purpose amateur radio communication satellite relaying information back to earth, (4) to demonstrate the feasibility of the deployment in low earth orbit of advanced technology such as the Gallium Arsenide Solar Cells, Nickel Metal Hydride batteries, and multi-chip module technology and, (5) to support student's active participation in applying the disciplines of engineering and science to space-based hardware platforms. The project includes the Three-axis Accelerometer System, TAS, Experiment which is designed to report the accelerations that the satellite undergoes during the tethering operations and during the second phase of the mission when the free floating satellite comes in contact with orbit debris. The SEASIS (SEDS Earth, Atmosphere, and Space Imaging System) is another SEDSAT experiment designed to provide images of the tether during its deployment and the earth during the second phase of the mission. To control these experiments and virtually all other satellite operations the Command Data System, CDS is employed. This system utilizes a moderate complexity micro-controller controlled by tasks operating under a real-time operating system to dynamically monitor and control the satellite. The scope of this researchers efforts has been in the general area of coordinating and assisting the student researchers with the development of the CDS and ground station interfaces. This included the low level CDS hardware design and the formulization of a general software plan and schedule for both the CDS and ground station portions of the project.

Engineering a mobile health tool for resource-poor settings to assess and manage cardiovascular disease risk: SMARThealth study.

PubMed

Raghu, Arvind; Praveen, Devarsetty; Peiris, David; Tarassenko, Lionel; Clifford, Gari

2015-04-29

The incidence of chronic diseases in low- and middle-income countries is rapidly increasing both in urban and rural regions. A major challenge for health systems globally is to develop innovative solutions for the prevention and control of these diseases. This paper discusses the development and pilot testing of SMARTHealth, a mobile-based, point-of-care Clinical Decision Support (CDS) tool to assess and manage cardiovascular disease (CVD) risk in resource-constrained settings. Through pilot testing, the preliminary acceptability, utility, and efficiency of the CDS tool was obtained. The CDS tool was part of an mHealth system comprising a mobile application that consisted of an evidence-based risk prediction and management algorithm, and a server-side electronic medical record system. Through an agile development process and user-centred design approach, key features of the mobile application that fitted the requirements of the end users and environment were obtained. A comprehensive analytics framework facilitated a data-driven approach to investigate four areas, namely, system efficiency, end-user variability, manual data entry errors, and usefulness of point-of-care management recommendations to the healthcare worker. A four-point Likert scale was used at the end of every risk assessment to gauge ease-of-use of the system. The system was field-tested with eleven village healthcare workers and three Primary Health Centre doctors, who screened a total of 292 adults aged 40 years and above. 34% of participants screened by health workers were identified by the CDS tool to be high CVD risk and referred to a doctor. In-depth analysis of user interactions found the CDS tool feasible for use and easily integrable into the workflow of healthcare workers. Following completion of the pilot, further technical enhancements were implemented to improve uptake of the mHealth platform. It will then be evaluated for effectiveness and cost-effectiveness in a cluster randomized controlled trial involving 54 southern Indian villages and over 16000 individuals at high CVD risk. An evidence-based CVD risk prediction and management tool was used to develop an mHealth platform in rural India for CVD screening and management with proper engagement of health care providers and local communities. With over a third of screened participants being high risk, there is a need to demonstrate the clinical impact of the mHealth platform so that it could contribute to improved CVD detection in high risk low resource settings.

Simulation of sovereign CDS market based on interaction between market participant

NASA Astrophysics Data System (ADS)

Ko, Bonggyun; Kim, Kyungwon

2017-08-01

A research for distributional property of financial asset is the subject of intense interest not only for financial theory but also for practitioner. Such respect is no exception to CDS market. The CDS market, which began to receive attention since the global financial debacle, is not well researched despite of the importance of research necessity. This research introduces creation of CDS market and use Ising system utilizing occurrence characteristics (to shift risk) as an important factor. Therefore the results of this paper would be of great assistance to both financial theory and practice. From this study, not only distributional property of the CDS market but also various statistics like multifractal characteristics could promote understanding about the market. A salient point in this study is that countries are mainly clustering into 2 groups and it might be because of market situation and geographical characteristics of each country. This paper suggested 2 simulation parameters representing this market based on understanding such CDS market situation. The estimated parameters are suitable for high and low risk event of CDS market respectively and these two parameters are complementary and can cover not only basic statistics but also multifractal properties of most countries. Therefore these estimated parameters can be used in researches preparing for a certain event (high or low risk). Finally this research will serve as a momentum double-checking indirectly the performance of Ising system based on these results.

The Role Of Driver Inattention In Crashes; New Statistics From The 1995 Crashworthiness Data System

DOT National Transportation Integrated Search

1996-08-08

INTELLIGENT VEHICLE INITIATIVE OR IVI : IN 1995, NHTSA BEGAN EMPLOYING THE CRASHWORTHINESS DATA SYSTEM (CDS) TO OBTAIN MORE IN-DEPTH INFORMATION ON DRIVER INATTENTION-RELATED CRASH CAUSES, INCLUDING DROWSINESS AND MANY FORMS OF DISTRACTION. CDS IS PO...

Credit Default Swaps networks and systemic risk

PubMed Central

Puliga, Michelangelo; Caldarelli, Guido; Battiston, Stefano

2014-01-01

Credit Default Swaps (CDS) spreads should reflect default risk of the underlying corporate debt. Actually, it has been recognized that CDS spread time series did not anticipate but only followed the increasing risk of default before the financial crisis. In principle, the network of correlations among CDS spread time series could at least display some form of structural change to be used as an early warning of systemic risk. Here we study a set of 176 CDS time series of financial institutions from 2002 to 2011. Networks are constructed in various ways, some of which display structural change at the onset of the credit crisis of 2008, but never before. By taking these networks as a proxy of interdependencies among financial institutions, we run stress-test based on Group DebtRank. Systemic risk before 2008 increases only when incorporating a macroeconomic indicator reflecting the potential losses of financial assets associated with house prices in the US. This approach indicates a promising way to detect systemic instabilities. PMID:25366654

Credit Default Swaps networks and systemic risk.

PubMed

Puliga, Michelangelo; Caldarelli, Guido; Battiston, Stefano

2014-11-04

Credit Default Swaps (CDS) spreads should reflect default risk of the underlying corporate debt. Actually, it has been recognized that CDS spread time series did not anticipate but only followed the increasing risk of default before the financial crisis. In principle, the network of correlations among CDS spread time series could at least display some form of structural change to be used as an early warning of systemic risk. Here we study a set of 176 CDS time series of financial institutions from 2002 to 2011. Networks are constructed in various ways, some of which display structural change at the onset of the credit crisis of 2008, but never before. By taking these networks as a proxy of interdependencies among financial institutions, we run stress-test based on Group DebtRank. Systemic risk before 2008 increases only when incorporating a macroeconomic indicator reflecting the potential losses of financial assets associated with house prices in the US. This approach indicates a promising way to detect systemic instabilities.

Credit Default Swaps networks and systemic risk

NASA Astrophysics Data System (ADS)

Puliga, Michelangelo; Caldarelli, Guido; Battiston, Stefano

2014-11-01

Credit Default Swaps (CDS) spreads should reflect default risk of the underlying corporate debt. Actually, it has been recognized that CDS spread time series did not anticipate but only followed the increasing risk of default before the financial crisis. In principle, the network of correlations among CDS spread time series could at least display some form of structural change to be used as an early warning of systemic risk. Here we study a set of 176 CDS time series of financial institutions from 2002 to 2011. Networks are constructed in various ways, some of which display structural change at the onset of the credit crisis of 2008, but never before. By taking these networks as a proxy of interdependencies among financial institutions, we run stress-test based on Group DebtRank. Systemic risk before 2008 increases only when incorporating a macroeconomic indicator reflecting the potential losses of financial assets associated with house prices in the US. This approach indicates a promising way to detect systemic instabilities.

Highly fluorescent carbon dots for visible sensing of doxorubicin release based on efficient nanosurface energy transfer.

PubMed

Wang, Beibei; Wang, Shujun; Wang, Yanfang; Lv, Yan; Wu, Hao; Ma, Xiaojun; Tan, Mingqian

2016-01-01

To prepare fluorescent carbon dots for loading cationic anticancer drug through donor-quenched nanosurface energy transfer in visible sensing of drug release. Highly fluorescent carbon dots (CDs) were prepared by a facile hydrothermal approach from citric acid and o-phenylenediamine. The obtained CDs showed a high quantum yield of 46 % and exhibited good cytocompatibility even at 1 mg/ml. The cationic anticancer drug doxorubicin (DOX) can be loaded onto the negatively charged CDs through electrostatic interactions. Additionally, the fluorescent CDs feature reversible donor-quenched mode nanosurface energy transfer. When loading the energy receptor DOX, the donor CDs' fluorescence was switched "off", while it turned "on" again after DOX release from the surface through endocytic uptake. Most DOX molecules were released from the CDs after 6 h incubation and entered cell nuclear region after 8 h, suggesting the drug delivery system may have potential for visible sensing in drug release.

STFM's National Clerkship Curriculum: CERA reveals impact, clerkship director needs.

PubMed

Cochella, Susan; Steiner, Beat D; Clinch, C Randall; WinklerPrins, Vince

2014-06-01

Consistency is needed in family medicine clerkships nationwide. The Society of Teachers of Family Medicine's (STFM) National Clerkship Curriculum (NCC) and supporting NCC website have been developed to address this need. A survey was used to measure these tools' effect and guide future improvements. The Council of Academic Family Medicine's (CAFM) Educational Research Alliance (CERA) 2012 survey of clerkship directors (CD) was used to answer two research questions: (1) To what extent are clerkships teaching the minimum core curriculum? and (2) What resources do clerkship directors identify as important in their role? The survey response rate was 66% (88/134). Ninety-two percent of these CDs are aware of the NCC, 74% report having visited the NCC website, and 71% plan to visit it more than once per year in the future. A total of 21.6% strongly agree that their clerkship content matches the NCC. CDs rate the quality of materials on the website as high and place greatest value on materials that can be downloaded and adapted to their clerkships. STFM's NCC website and materials are familiar to CDs although only one in five state their clerkship curriculum matches the NCC minimum core curriculum. The NCC editorial board needs to better understand why so few teach curriculum that closely matches the minimum core. Continued outreach to CDs can answer this question and improve our ability to support CDs as they incorporate the NCC into family medicine clerkships.

Development of a Higher Fidelity Model for the Cascade Distillation Subsystem (CDS)

NASA Technical Reports Server (NTRS)

Perry, Bruce; Anderson, Molly

2014-01-01

Significant improvements have been made to the ACM model of the CDS, enabling accurate predictions of dynamic operations with fewer assumptions. The model has been utilized to predict how CDS performance would be impacted by changing operating parameters, revealing performance trade-offs and possibilities for improvement. CDS efficiency is driven by the THP coefficient of performance, which in turn is dependent on heat transfer within the system. Based on the remaining limitations of the simulation, priorities for further model development include: center dot Relaxing the assumption of total condensation center dot Incorporating dynamic simulation capability for the buildup of dissolved inert gasses in condensers center dot Examining CDS operation with more complex feeds center dot Extending heat transfer analysis to all surfaces

Fabrication of luminescent CdS nanoparticles on short-peptide-based hydrogel nanofibers: tuning of optoelectronic properties.

PubMed

Palui, Goutam; Nanda, Jayanta; Ray, Sudipta; Banerjee, Arindam

2009-07-13

The pH-induced self-assembly of three synthetic tripeptides in water medium is used to immobilize luminescent CdS nanoparticles. These peptides form a nanofibrillar network structure upon gelation in aqueous medium at basic pH values (pH 11.0-13.0), and the fabrication of CdS nanoparticles on the gel nanofiber confers the luminescent property to these gels. Atomic force microscopy, field-emission scanning electron microscopy, and high-resolution transmission electron microscopy clearly reveal the presence of CdS nanoparticles in a well-defined array on the gel nanofibers. This is a convenient way to make organic nanofiber-inorganic nanoparticle hybrid nanocomposite systems. The size of the CdS nanoparticles remains almost same before and after deposition on the gel nanofiber. Photoluminescence (PL) measurement of the CdS nanoparticles upon deposition on the gel nanofibers shows a significant blue shift in the emission spectrum of the nanoparticles, and there is a considerable change in the PL gap energy of the CdS nanoparticles after immobilization on different gel nanofibrils. This finding suggests that the optoelectronic properties of CdS nanoparticles can be tuned upon deposition on gel nanofibers without changing the size of the nanoparticles.

EMR-based medical knowledge representation and inference via Markov random fields and distributed representation learning.

PubMed

Zhao, Chao; Jiang, Jingchi; Guan, Yi; Guo, Xitong; He, Bin

2018-05-01

Electronic medical records (EMRs) contain medical knowledge that can be used for clinical decision support (CDS). Our objective is to develop a general system that can extract and represent knowledge contained in EMRs to support three CDS tasks-test recommendation, initial diagnosis, and treatment plan recommendation-given the condition of a patient. We extracted four kinds of medical entities from records and constructed an EMR-based medical knowledge network (EMKN), in which nodes are entities and edges reflect their co-occurrence in a record. Three bipartite subgraphs (bigraphs) were extracted from the EMKN, one to support each task. One part of the bigraph was the given condition (e.g., symptoms), and the other was the condition to be inferred (e.g., diseases). Each bigraph was regarded as a Markov random field (MRF) to support the inference. We proposed three graph-based energy functions and three likelihood-based energy functions. Two of these functions are based on knowledge representation learning and can provide distributed representations of medical entities. Two EMR datasets and three metrics were utilized to evaluate the performance. As a whole, the evaluation results indicate that the proposed system outperformed the baseline methods. The distributed representation of medical entities does reflect similarity relationships with respect to knowledge level. Combining EMKN and MRF is an effective approach for general medical knowledge representation and inference. Different tasks, however, require individually designed energy functions. Copyright © 2018 Elsevier B.V. All rights reserved.

Water table management reduces tile nitrate loss in continuous corn and in a soybean-corn rotation.

PubMed

Drury, C F; Tan, C S; Gaynor, J D; Reynolds, W D; Welacky, T W; Oloya, T O

2001-10-25

Water table management systems can be designed to alleviate soil water excesses and deficits, as well as reduce nitrate leaching losses in tile discharge. With this in mind, a standard tile drainage (DR) system was compared over 8 years (1991 to 1999) to a controlled tile drainage/subirrigation (CDS) system on a low-slope (0.05 to 0.1%) Brookston clay loam soil (Typic Argiaquoll) in southwestern Ontario, Canada. In the CDS system, tile discharge was controlled to prevent excessive drainage, and water was pumped back up the tile lines (subirrigation) to replenish the crop root zone during water deficit periods. In the first phase of the study (1991 to 1994), continuous corn (Zea mays, L.) was grown with annual nitrogen (N) fertilizer inputs as per local soil test recommendations. In the second phase (1995 to 1999), a soybean (Glycine max L., Merr.)-corn rotation was used with N fertilizer added only during the two corn years. In Phase 1 when continuous corn was grown, CDS reduced total tile discharge by 26% and total nitrate loss in tile discharge by 55%, compared to DR. In addition, the 4-year flow weighted mean (FWM) nitrate concentration in tile discharge exceeded the Canadian drinking water guideline (10 mg N l(-1)) under DR (11.4 mg N l(-1)), but not under CDS (7.0 mg N l(-1)). In Phase 2 during the soybean-corn rotation, CDS reduced total tile discharge by 38% and total nitrate loss in tile discharge by 66%, relative to DR. The 4-year FWM nitrate concentration during Phase 2 in tile discharge was below the drinking water guideline for both DR (7.3 mg N l(-1)) and CDS (4.0 mg N l(-1)). During both phases of the experiment, the CDS treatment caused only minor increases in nitrate loss in surface runoff relative to DR. Hence CDS decreased FWM nitrate concentrations, total drainage water loss, and total nitrate loss in tile discharge relative to DR. In addition, soybean-corn rotation reduced FWM nitrate concentrations and total nitrate loss in tile discharge relative to continuous corn. CDS and crop rotations with reduced N fertilizer inputs can thus improve the quality of tile discharge water substantially.

Novel optical properties of CdS:Zn rocksalt system (a theoretical study)

NASA Astrophysics Data System (ADS)

Khan, M. Junaid Iqbal; Nauman Usmani, M.; Kanwal, Zarfishan

2017-11-01

In present computational study, we focus on optical properties of Zn doped CdS for 1  ×  1  ×  2 and 2  ×  2  ×  2 supercell configurations. Cd atoms are substituted with Zn atoms and results for optical properties demonstrate different trends due to interaction of Zn with S atoms. The study has been performed by PBE-GGA approach using Wien2K within framework of DFT. TDOS and PDOS represent that S-3p states are responsible for conduction. For large supercell configuration, a tremendous change in optical properties has been observed due to different bonding. Optical absorption tends to increase in visible range which supports candidacy of Zn doped CdS for enhanced optoelectronic and nanotechnology applications.

Flow-injection chemiluminescence analysis for sensitive determination of atenolol using cadmium sulfide quantum dots

NASA Astrophysics Data System (ADS)

Khataee, Alireza; Lotfi, Roya; Hasanzadeh, Aliyeh; Iranifam, Mortaza; Joo, Sang Woo

2016-03-01

A sensitive, rapid and simple flow-injection chemiluminescence (CL) system based on the light emitted from KMnO4-cadmium sulfide quantum dots (CdS QDs) reaction in the presence of cetyltrimethylammonium bromide (CTAB) in acidic medium was developed as a CL probe for the sensitive determination of atenolol. Optical and structural features of CdS QDs capped with L-cysteine, which synthesized via hydrothermal approach, were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), and UV-Vis spectroscopy. The CL intensity of KMnO4-CdS QDs-CTAB was remarkably enhanced in the presence of trace level of atenolol. Under optimum experimental conditions, there is a linear relationship between the increase in CL intensity of KMnO4-CdS QDs-CTAB system and atenolol concentration in a range of 0.001 to 4.0 mg L- 1 and 4.0 to 18.0 mg L- 1, with a detection limit (3σ) of 0.0010 mg L- 1. A possible mechanism for KMnO4-CdS QDs-CTAB-atenolol CL reaction is proposed. To prove the practical application of the KMnO4-CdS QDs-CTAB CL method, the method was applied for the determination of atenolol in spiked environmental water samples and commercial pharmaceutical formulation. Furthermore, corona discharge ionization ion mobility spectrometry (CD-IMS) technique was utilized for determination of atenolol. Figure S2. Optimization of the CL reaction conditions: (a) effect of KMnO4 concentration. Conditions: the concentrations of H2SO4, CdS QDs and atenolol were 1 mol L-1, 0.35 mol L-1, and 4.0 mg L-1, respectively; (b) effect of acidic media. Conditions: the concentrations of KMnO4 was 0.04 mmol L-1, other conditions were as in (a); (c) effect of CdS QDs concentration. Conditions: H2SO4 concentration was 1.0 mol L-1, other conditions were as in (b), and (d) effect of CTAB concentration. Conditions: CdS QDs concentration was 0.35 mmol L-1, other conditions were as in (c). Figure S3. UV-Vis absorption spectra of KMnO4-CdS QDs-atenolol CL system, recorded at different time intervals after their mixing. Conditions: the concentrations of KMnO4, CdS QDs, H2SO4 and atenolol were 0.04 mmol L-1, 0.35 mmol L-1, 1.0 mol L-1 and 4.0 mg L-1, respectively.

Mini-Micro CDS/ISIS in the Thailand Development Research Institute Library.

ERIC Educational Resources Information Center

Wongkoltoot, Poonsin; Indee, Somsak

1992-01-01

Describes the Thailand Development Research Institute Library's development of an integrated bibliographic system using UNESCO's Micro-ISIS software. Linkages between databases were made using an in-house application (TIBIS) written in CDS/ISIS Pascal. The library system is available on a local area network (LAN). (three references) (EA)

Effects of air annealing on CdS quantum dots thin film grown at room temperature by CBD technique intended for photosensor applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shaikh, Shaheed U.; Desale, Dipalee J.; Siddiqui, Farha Y.

2012-11-15

Graphical abstract: The effect of different intensities (40, 60 100 and 200 W) of light on CdS quantum dots thin film annealed at 350 °C indicating enhancement in (a) photo-current and (b) photosensitivity. Highlights: ► The preparation of CdS nanodot thin film at room temperature by M-CBD technique. ► Study of air annealing on prepared CdS nanodots thin film. ► The optimized annealing temperature for CdS nanodot thin film is 350 °C. ► Modified CdS thin films can be used in photosensor application. -- Abstract: CdS quantum dots thin-films have been deposited onto the glass substrate at room temperature usingmore » modified chemical bath deposition technique. The prepared thin films were further annealed in air atmosphere at 150, 250 and 350 °C for 1 h and subsequently characterized by scanning electron microscopy, ultraviolet–visible spectroscopy, electrical resistivity and I–V system. The modifications observed in morphology and opto-electrical properties of the thin films are presented.« less

Carbon dots as fluorescent probes for "off-on" detection of Cu2+ and L-cysteine in aqueous solution.

PubMed

Zong, Jie; Yang, Xiaoling; Trinchi, Adrian; Hardin, Simon; Cole, Ivan; Zhu, Yihua; Li, Chunzhong; Muster, Tim; Wei, Gang

2014-01-15

Copper ion (Cu(2+)) and L-cysteine (L-Cys) detection is critically important since an abnormal level of Cu(2+) or L-Cys is an indicator for many diseases. In this paper, we demonstrate an "off-on" approach for highly sensitive and selective detection of Cu(2+) and L-Cys using carbon dots (CDs) as fluorescent probes. CDs were prepared by using mesoporous silica (MS) spheres as nanoreactors. The binding ability of CDs towards metal ions was examined by comparing the fluorescence intensities of CDs before and after the addition of the metal ions. The addition of Cu(2+) cations leads to their absorption on the surface of CDs and the significant fluorescence quench of CDs (turn-off). The resulting in CDs-Cu(2+) system was found to be sensitive to L-Cys. The addition of L-Cys not only serves to shelter the CDs effectively from being quenched, but also to reverse the quenching and restore the fluorescence (turn-on) due to its ability to remove Cu(2+) from the surface of CDs. This method is facile, rapid, low cost, and environment-friendly. A detection limit as low as 2.3×10(-8) M for Cu(2+) and 3.4×10(-10) M for L-Cys is obtained, which is promising for biological applications. © 2013 Elsevier B.V. All rights reserved.

Participatory design of probability-based decision support tools for in-hospital nurses.

PubMed

Jeffery, Alvin D; Novak, Laurie L; Kennedy, Betsy; Dietrich, Mary S; Mion, Lorraine C

2017-11-01

To describe nurses' preferences for the design of a probability-based clinical decision support (PB-CDS) tool for in-hospital clinical deterioration. A convenience sample of bedside nurses, charge nurses, and rapid response nurses (n = 20) from adult and pediatric hospitals completed participatory design sessions with researchers in a simulation laboratory to elicit preferred design considerations for a PB-CDS tool. Following theme-based content analysis, we shared findings with user interface designers and created a low-fidelity prototype. Three major themes and several considerations for design elements of a PB-CDS tool surfaced from end users. Themes focused on "painting a picture" of the patient condition over time, promoting empowerment, and aligning probability information with what a nurse already believes about the patient. The most notable design element consideration included visualizing a temporal trend of the predicted probability of the outcome along with user-selected overlapping depictions of vital signs, laboratory values, and outcome-related treatments and interventions. Participants expressed that the prototype adequately operationalized requests from the design sessions. Participatory design served as a valuable method in taking the first step toward developing PB-CDS tools for nurses. This information about preferred design elements of tools that support, rather than interrupt, nurses' cognitive workflows can benefit future studies in this field as well as nurses' practice. Published by Oxford University Press on behalf of the American Medical Informatics Association 2017. This work is written by US Government employees and is in the public domain in the United States.

Computerized clinical documentation system in the pediatric intensive care unit

PubMed Central

2001-01-01

Background To determine whether a computerized clinical documentation system (CDS): 1) decreased time spent charting and increased time spent in patient care; 2) decreased medication errors; 3) improved clinical decision making; 4) improved quality of documentation; and/or 5) improved shift to shift nursing continuity. Methods Before and after implementation of CDS, a time study involving nursing care, medication delivery, and normalization of serum calcium and potassium values was performed. In addition, an evaluation of completeness of documentation and a clinician survey of shift to shift reporting were also completed. This was a modified one group, pretest-posttest design. Results With the CDS there was: improved legibility and completeness of documentation, data with better accessibility and accuracy, no change in time spent in direct patient care or charting by nursing staff. Incidental observations from the study included improved management functions of our nurse manager; improved JCAHO documentation compliance; timely access to clinical data (labs, vitals, etc); a decrease in time and resource use for audits; improved reimbursement because of the ability to reconstruct lost charts; limited human data entry by automatic data logging; eliminated costs of printing forms. CDS cost was reasonable. Conclusions When compared to a paper chart, the CDS provided a more legible, compete, and accessible patient record without affecting time spent in direct patient care. The availability of the CDS improved shift to shift reporting. Other observations showed that the CDS improved management capabilities; helped physicians deliver care; improved reimbursement; limited data entry errors; and reduced costs. PMID:11604105

The next chapter in patient blood management: real-time clinical decision support.

PubMed

Goodnough, Lawrence Tim; Shah, Neil

2014-12-01

Blood transfusion was identified by the American Medical Association as one of the top five most frequently overused therapies. Utilization review has been required by accreditation agencies, but retrospective review has been ineffective due to labor-intense resources applied to only a sampling of transfusion events. Electronic medical records have allowed clinical decision support (CDS) to occur via a best practices alert at the critical decision point concurrently with physician order entry. We review emerging strategies for improving blood utilization. Implementation of CDS at our institution decreased the percentage of transfusions in patients with a hemoglobin level of more than 8 g/dL from 60% to less than 30%. Annual RBC transfusions were reduced by 24%, despite concurrent increases in patient discharge volumes and case mix complexity. This resulted in acquisition costs savings (direct blood product purchase costs) of $6.4 million over 4 years. We have been able to significantly reduce inappropriate blood transfusions and related costs through an educational initiative coupled with real-time CDS. In deriving increased value out of health care, CDS can be applied to a number of overuse measures in laboratory testing, radiology, and therapy such as antibiotics, as outlined by the American Board of Internal Medicine's Choosing Wisely campaign. Copyright© by the American Society for Clinical Pathology.

Usability Testing of a Complex Clinical Decision Support Tool in the Emergency Department: Lessons Learned.

PubMed

Press, Anne; McCullagh, Lauren; Khan, Sundas; Schachter, Andy; Pardo, Salvatore; McGinn, Thomas

2015-09-10

As the electronic health record (EHR) becomes the preferred documentation tool across medical practices, health care organizations are pushing for clinical decision support systems (CDSS) to help bring clinical decision support (CDS) tools to the forefront of patient-physician interactions. A CDSS is integrated into the EHR and allows physicians to easily utilize CDS tools. However, often CDSS are integrated into the EHR without an initial phase of usability testing, resulting in poor adoption rates. Usability testing is important because it evaluates a CDSS by testing it on actual users. This paper outlines the usability phase of a study, which will test the impact of integration of the Wells CDSS for pulmonary embolism (PE) diagnosis into a large urban emergency department, where workflow is often chaotic and high stakes decisions are frequently made. We hypothesize that conducting usability testing prior to integration of the Wells score into an emergency room EHR will result in increased adoption rates by physicians. The objective of the study was to conduct usability testing for the integration of the Wells clinical prediction rule into a tertiary care center's emergency department EHR. We conducted usability testing of a CDS tool in the emergency department EHR. The CDS tool consisted of the Wells rule for PE in the form of a calculator and was triggered off computed tomography (CT) orders or patients' chief complaint. The study was conducted at a tertiary hospital in Queens, New York. There were seven residents that were recruited and participated in two phases of usability testing. The usability testing employed a "think aloud" method and "near-live" clinical simulation, where care providers interacted with standardized patients enacting a clinical scenario. Both phases were audiotaped, video-taped, and had screen-capture software activated for onscreen recordings. Phase I: Data from the "think-aloud" phase of the study showed an overall positive outlook on the Wells tool in assessing a patient for a PE diagnosis. Subjects described the tool as "well-organized" and "better than clinical judgment". Changes were made to improve tool placement into the EHR to make it optimal for decision-making, auto-populating boxes, and minimizing click fatigue. Phase II: After incorporating the changes noted in Phase 1, the participants noted tool improvements. There was less toggling between screens, they had all the clinical information required to complete the tool, and were able to complete the patient visit efficiently. However, an optimal location for triggering the tool remained controversial. This study successfully combined "think-aloud" protocol analysis with "near-live" clinical simulations in a usability evaluation of a CDS tool that will be implemented into the emergency room environment. Both methods proved useful in the assessment of the CDS tool and allowed us to refine tool usability and workflow.

Model documentation, Coal Market Module of the National Energy Modeling System

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

This report documents the objectives and the conceptual and methodological approach used in the development of the National Energy Modeling System`s (NEMS) Coal Market Module (CMM) used to develop the Annual Energy Outlook 1998 (AEO98). This report catalogues and describes the assumptions, methodology, estimation techniques, and source code of CMM`s two submodules. These are the Coal Production Submodule (CPS) and the Coal Distribution Submodule (CDS). CMM provides annual forecasts of prices, production, and consumption of coal for NEMS. In general, the CDS integrates the supply inputs from the CPS to satisfy demands for coal from exogenous demand models. The internationalmore » area of the CDS forecasts annual world coal trade flows from major supply to major demand regions and provides annual forecasts of US coal exports for input to NEMS. Specifically, the CDS receives minemouth prices produced by the CPS, demand and other exogenous inputs from other NEMS components, and provides delivered coal prices and quantities to the NEMS economic sectors and regions.« less

One-step hydrothermal synthesis of chiral carbon dots and their effects on mung bean plant growth.

PubMed

Zhang, Mengling; Hu, Lulu; Wang, Huibo; Song, Yuxiang; Liu, Yang; Li, Hao; Shao, Mingwang; Huang, Hui; Kang, Zhenhui

2018-06-27

Chiral compounds/materials have important effects on the growth of plants. Chiral carbon dots (CDs), as an emerging chiral carbon nanomaterial, have great potential in bio-application and bio-nanotechnology. Herein, we report a hydrothermal method to synthesize chiral CDs from cysteine (cys) and citric acid. These chiral CDs were further demonstrated to have systemic effects on the growth of mung bean plants, in which case both l- and d-CDs can promote the growth of the root in mung bean plants, stem length of mung bean sprouts and water absorption of bean seeds. The elongation of mung bean sprouts presented an increasing trend with the treatment of chiral CDs of increasing concentration (below 500 μg mL-1). Furthermore, in the optimal concentration (100 μg mL-1), the l-CDs can improve root vigor and the activity of the Rubisco enzyme of bean sprouts by 8.4% and 20.5%, while the d-CDs increased by 28.9% and 67.5%. Due to more superior properties in improving root vigor and the activity of the Rubisco enzyme of mung bean sprouts, d-CDs are able to enhance photosynthesis better and accumulate more carbohydrate in mung bean plants.

Development of an Exploration-Class Cascade Distillation Subsystem: Performance Testing of the Generation 1.0 Prototype

NASA Technical Reports Server (NTRS)

Callahan, Michael R.; Sargusingh, Miriam J.

2015-01-01

The ability to recover and purify water is crucial for realizing long-term human space missions. The National Aeronautics and Space Admininstration and Honeywell co-developed a five-stage vacuum rotary distillation water recovery system referred to as the Cascade Distillation Subsystem (CDS). Over the past three years, NASA's Advanced Exploration Systems (AES) Water Recovery Project (WRP) has been working toward the development of a flight-forward CDS design. In 2012 the original CDS prototype underwent a series of incremental upgrades and tests intened to both demonstrate the feasibility of a on-orbit demonstration of the system and to collect operational and performance data to be used to inform a second generation design. The latest testing of the CDS Generation 1.0 prototype was conducted May 29 through July 2, 2014. Initial system performance was benchmarked by processing deionized water and sodium chloride. Following, the system was challenged with analogue urine waste stream solutions stabilized with an Oxone-based and the two International Space Station baseline and alternative pretreatment solutions. During testing, the system processed more than 160 kilograms of wastewater with targeted water recoveries between 75 and 85% depending on the specific waste stream tested. For all wastewater streams, contaminant removals from wastewater feed to product water distillate, were estimated at greater than 99%. The average specific energy of the system was less than 120 Watt-hours/kilogram. The following paper provides detailed information and data on the performance of the CDS as challenged per the WRP test objectives.

Maximize Institutional Relationships with CRMs. CDS Spotlight Report. ECAR Research Bulletin

ERIC Educational Resources Information Center

Lang, Leah; Pirani, Judith A.

2014-01-01

This Spotlight focuses on data from the 2013 Core Data Service (CDS) to better understand how higher education institutions approach customer relationship management (CRM) systems. Information provided for this Spotlight was derived from Module 8 of the Core Data survey, which asked several questions regarding information systems and applications.…

Embracing Connectedness and Change: A Complex Dynamic Systems Perspective for Applied Linguistic Research

ERIC Educational Resources Information Center

Cameron, Lynne

2015-01-01

Complex dynamic systems (CDS) theory offers a powerful metaphorical model of applied linguistic processes, allowing holistic descriptions of situated phenomena, and addressing the connectedness and change that often characterise issues in our field. A recent study of Kenyan conflict transformation illustrates application of a CDS perspective. Key…

Advancing clinical decision support using lessons from outside of healthcare: an interdisciplinary systematic review.

PubMed

Wu, Helen W; Davis, Paul K; Bell, Douglas S

2012-08-17

Greater use of computerized decision support (DS) systems could address continuing safety and quality problems in healthcare, but the healthcare field has struggled to implement DS technology. This study surveys DS experience across multiple non-healthcare disciplines for new insights that are generalizable to healthcare provider decisions. In particular, it sought design principles and lessons learned from the other disciplines that could inform efforts to accelerate the adoption of clinical decision support (CDS). Our systematic review drew broadly from non-healthcare databases in the basic sciences, social sciences, humanities, engineering, business, and defense: PsychINFO, BusinessSource Premier, Social Sciences Abstracts, Web of Science, and Defense Technical Information Center. Because our interest was in DS that could apply to clinical decisions, we selected articles that (1) provided a review, overview, discussion of lessons learned, or an evaluation of design or implementation aspects of DS within a non-healthcare discipline and (2) involved an element of human judgment at the individual level, as opposed to decisions that can be fully automated or that are made at the organizational level. Clinical decisions share some similarities with decisions made by military commanders, business managers, and other leaders: they involve assessing new situations and choosing courses of action with major consequences, under time pressure, and with incomplete information. We identified seven high-level DS system design features from the non-healthcare literature that could be applied to CDS: providing broad, system-level perspectives; customizing interfaces to specific users and roles; making the DS reasoning transparent; presenting data effectively; generating multiple scenarios covering disparate outcomes (e.g., effective; effective with side effects; ineffective); allowing for contingent adaptations; and facilitating collaboration. The article provides examples of each feature. The DS literature also emphasizes the importance of organizational culture and training in implementation success. The literature contrasts "rational-analytic" vs. "naturalistic-intuitive" decision-making styles, but the best approach is often a balanced approach that combines both styles. It is also important for DS systems to enable exploration of multiple assumptions, and incorporation of new information in response to changing circumstances. Complex, high-level decision-making has common features across disciplines as seemingly disparate as defense, business, and healthcare. National efforts to advance the health information technology agenda through broader CDS adoption could benefit by applying the DS principles identified in this review.

Transition metal doped (X = V, Cr) CdS monolayer: A DFT study

NASA Astrophysics Data System (ADS)

Deb, Jyotirmoy; Paul, Debolina; Sarkar, Utpal

2018-05-01

In this work based on density functional theory approach with generalized gradient approximation we have investigated the effect doping and co-doping of transition metal atoms in CdS monolayer sheet. On the basis cohesive energy, we have determined the stability of all the transition metal doped systems. CdS monolayer is of nonmagnetic character but the insertion of transition metal atoms introduces the spontaneous spin polarization which results in a significant value of magnetic moment. The band structure analysis reveals that three different types of conducting nature such as spin-select-half-semiconductor, half metallic and metallic nature with total spin polarization has also been observed. The versatile conducting nature of the transition metal doped CdS monolayer predicts the possibility of using these systems in spintronics mainly as a spin filter and also to form metal-semiconductor interface etc. at nanoscale level.

Tricolor White-Light-Emitting Carbon Dots with Multiple-Cores@Shell Structure for WLED Application.

PubMed

Zhang, Tianyi; Zhao, Feifei; Li, Li; Qi, Bin; Zhu, Dongxia; Lü, Jianhua; Lü, Changli

2018-06-13

The past few years have witnessed the rapid development of carbon dots (CDs) due to their outstanding optical properties and a wide range of applications. However, the design and control of CDs with long-wavelength multicolor emission are still huge challenges to be addressed for their practical use in different fields. Here, novel nitrogen-doped multiple-core@shell-structured AC-CDs with tricolor emissions of red, green, and blue were constructed via one-pot hydrothermal method from 5-amino-1,10-phenanthroline and citric acid as reactants and the growth process of AC-CDs was monitored with the reaction time in the synthetic system. The origin of different fluorescence emissions was explored using the unique coordination ability of the surface groups of AC-CDs. An obvious concentration dependence of fluorescent properties was observed for the as-prepared AC-CDs, and a highly fluorescent quantum yield (QY) of 67% for red emission at 630 nm can be obtained by adjusting concentration of AC-CDs. The pure white-light emission (0.33, 0.33; Commission Internationale de l'Elcairage coordinate) was carried out from single carbon dot with QY of 29% through regulation of the excitation and concentration of multiple-core@shell-structured AC-CDs. In addition, because of their excellent photoluminescent properties, the white-emitting AC-CDs as emitting phosphor can be easily used in the fabrication of white-light-emitting diode with good anti-photobleaching and temperature stability.

The Virtual Climate Data Server (vCDS): An iRODS-Based Data Management Software Appliance Supporting Climate Data Services and Virtualization-as-a-Service in the NASA Center for Climate Simulation

NASA Technical Reports Server (NTRS)

Schnase, John L.; Tamkin, Glenn S.; Ripley, W. David III; Stong, Savannah; Gill, Roger; Duffy, Daniel Q.

2012-01-01

Scientific data services are becoming an important part of the NASA Center for Climate Simulation's mission. Our technological response to this expanding role is built around the concept of a Virtual Climate Data Server (vCDS), repetitive provisioning, image-based deployment and distribution, and virtualization-as-a-service. The vCDS is an iRODS-based data server specialized to the needs of a particular data-centric application. We use RPM scripts to build vCDS images in our local computing environment, our local Virtual Machine Environment, NASA s Nebula Cloud Services, and Amazon's Elastic Compute Cloud. Once provisioned into one or more of these virtualized resource classes, vCDSs can use iRODS s federation capabilities to create an integrated ecosystem of managed collections that is scalable and adaptable to changing resource requirements. This approach enables platform- or software-asa- service deployment of vCDS and allows the NCCS to offer virtualization-as-a-service: a capacity to respond in an agile way to new customer requests for data services.

An information management system for patients with tuberculosis: usability assessment with end-users.

PubMed

Darby, Jonathan; Black, Jim; Morrison, David; Buising, Kirsty

2012-01-01

Information systems with clinical decision support (CDS) offer great potential to assist the co-ordination of patients with chronic diseases and to improve patient care. Despite this, few have entered routine clinical use. Tuberculosis (TB) is an infection of public health importance. It has complex interactions with many comorbid conditions, requires close supervised care and prolonged treatment for effective cure. These features make it suitable for use with an information management system with CDS features. In close consultation with key stakeholders, a clinical application was developed for the management of TB patients in Victoria. A formal usability assessment using semi-structured case-scenario based exercises was performed. Subjects were 12 individuals closely involved in the care of TB patients, including Infectious Diseases and Respiratory Physicians, and Public Health Nurses. Two researchers conducted the sessions, independently analysed responses and discrepancies compared to the voice record for validity. Despite varied computer experience, responses were positive regarding user interface and content. Data location was not always intuitive, however this improved with familiarity of the program. Decision support was considered valuable, with useful suggestions for expansion of these features. Automated reporting for correspondence and notification to the Health Department were felt worth the initial investment in data entry. An important workflow-based issue regarding dismissal of alerts and several errors were detected. Usability assessment validated many design elements of the system, provided a unique insight into workflow issues faced by users and hopefully will impact on its ultimate clinical utility.

Super-resolution depth information from a short-wave infrared laser gated-viewing system by using correlated double sampling

NASA Astrophysics Data System (ADS)

Göhler, Benjamin; Lutzmann, Peter

2017-10-01

Primarily, a laser gated-viewing (GV) system provides range-gated 2D images without any range resolution within the range gate. By combining two GV images with slightly different gate positions, 3D information within a part of the range gate can be obtained. The depth resolution is higher (super-resolution) than the minimal gate shift step size in a tomographic sequence of the scene. For a state-of-the-art system with a typical frame rate of 20 Hz, the time difference between the two required GV images is 50 ms which may be too long in a dynamic scenario with moving objects. Therefore, we have applied this approach to the reset and signal level images of a new short-wave infrared (SWIR) GV camera whose read-out integrated circuit supports correlated double sampling (CDS) actually intended for the reduction of kTC noise (reset noise). These images are extracted from only one single laser pulse with a marginal time difference in between. The SWIR GV camera consists of 640 x 512 avalanche photodiodes based on mercury cadmium telluride with a pixel pitch of 15 μm. A Q-switched, flash lamp pumped solid-state laser with 1.57 μm wavelength (OPO), 52 mJ pulse energy after beam shaping, 7 ns pulse length and 20 Hz pulse repetition frequency is used for flash illumination. In this paper, the experimental set-up is described and the operating principle of CDS is explained. The method of deriving super-resolution depth information from a GV system by using CDS is introduced and optimized. Further, the range accuracy is estimated from measured image data.

Carbon-Dots-Based Lab-On-a-Nanoparticle Approach for the Detection and Differentiation of Antibiotics.

PubMed

Qiao, Li'na; Qian, Sihua; Wang, Yuhui; Yan, Shifeng; Lin, Hengwei

2018-03-26

Fluorescent carbon dots (CDs) have received considerable attention in recent years due to their superior optical properties. To take further advantages of these unique features, herein, a CDs-based "lab-on-a-nanoparticle" approach for the detection and discrimination of antibiotics is developed. The sensing platform was designed based on the different channel's fluorescence recoveries or further quenching of the full-color emissive CDs (F-CDs) and metal ion ensembles upon the addition of antibiotics. The F-CDs exhibited unusually comparable emission intensity nearly across the entire visible spectrum even as the excitation wavelength is shifted, making it very suitable for the construction of multi-channel sensing systems. The sensing platform was fabricated on the basis of the competing interaction of metal ions with the F-CDs and antibiotics. Three metal ions (i.e., Cu 2+ , Ce 3+ and Eu 3+ ) can efficiently quench the fluorescence of the F-CDs. Upon the addition of antibiotics, the fluorescent intensities either recovered at different emission wavelengths or were further quenched to various degrees. The fluorescence response patterns at different emission wavelength were characteristic for each antibiotic and can be quantitatively differentiated by standard statistical methods (e.g., hierarchical clustering analysis and principal component analysis). Moreover, as an example, the proposed method was applied for quantitative detection of oxytetracycline with a limit of detection to be 0.06 μm. Finally, the sensing system was successfully employed for residual antibiotics detection and identification in real food samples. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Measuring agreement between decision support reminders: the cloud vs. the local expert.

PubMed

Dixon, Brian Edward; Simonaitis, Linas; Perkins, Susan M; Wright, Adam; Middleton, Blackford

2014-04-10

A cloud-based clinical decision support system (CDSS) was implemented to remotely provide evidence-based guideline reminders in support of preventative health. Following implementation, we measured the agreement between preventive care reminders generated by an existing, local CDSS and the new, cloud-based CDSS operating on the same patient visit data. Electronic health record data for the same set of patients seen in primary care were sent to both the cloud-based web service and local CDSS. The clinical reminders returned by both services were captured for analysis. Cohen's Kappa coefficient was calculated to compare the two sets of reminders. Kappa statistics were further adjusted for prevalence and bias due to the potential effects of bias in the CDS logic and prevalence in the relative small sample of patients. The cloud-based CDSS generated 965 clinical reminders for 405 patient visits over 3 months. The local CDSS returned 889 reminders for the same patient visit data. When adjusted for prevalence and bias, observed agreement varied by reminder from 0.33 (95% CI 0.24 - 0.42) to 0.99 (95% CI 0.97 - 1.00) and demonstrated almost perfect agreement for 7 of the 11 reminders. Preventive care reminders delivered by two disparate CDS systems show substantial agreement. Subtle differences in rule logic and terminology mapping appear to account for much of the discordance. Cloud-based CDSS therefore show promise, opening the door for future development and implementation in support of health care providers with limited resources for knowledge management of complex logic and rules.

Measuring agreement between decision support reminders: the cloud vs. the local expert

PubMed Central

2014-01-01

Background A cloud-based clinical decision support system (CDSS) was implemented to remotely provide evidence-based guideline reminders in support of preventative health. Following implementation, we measured the agreement between preventive care reminders generated by an existing, local CDSS and the new, cloud-based CDSS operating on the same patient visit data. Methods Electronic health record data for the same set of patients seen in primary care were sent to both the cloud-based web service and local CDSS. The clinical reminders returned by both services were captured for analysis. Cohen’s Kappa coefficient was calculated to compare the two sets of reminders. Kappa statistics were further adjusted for prevalence and bias due to the potential effects of bias in the CDS logic and prevalence in the relative small sample of patients. Results The cloud-based CDSS generated 965 clinical reminders for 405 patient visits over 3 months. The local CDSS returned 889 reminders for the same patient visit data. When adjusted for prevalence and bias, observed agreement varied by reminder from 0.33 (95% CI 0.24 – 0.42) to 0.99 (95% CI 0.97 – 1.00) and demonstrated almost perfect agreement for 7 of the 11 reminders. Conclusions Preventive care reminders delivered by two disparate CDS systems show substantial agreement. Subtle differences in rule logic and terminology mapping appear to account for much of the discordance. Cloud-based CDSS therefore show promise, opening the door for future development and implementation in support of health care providers with limited resources for knowledge management of complex logic and rules. PMID:24720863

Quantum dot sensitized solar cell based on TiO2/CdS/Ag2S heterostructure

NASA Astrophysics Data System (ADS)

Pawar, Sachin A.; Patil, Dipali S.; Kim, Jin Hyeok; Patil, Pramod S.; Shin, Jae Cheol

2017-04-01

Quantum dot sensitized solar cell (QDSSC) is fabricated based on a stepwise band structure of TiO2/CdS/Ag2S to improve the photoconversion efficiency of TiO2/CdS system by incorporating a low band gap Ag2S QDs. Vertically aligned TiO2 nanorods assembly is prepared by a simple hydrothermal technique. The formation of CdS and Ag2S QDs over TiO2 nanorods assembly as a photoanode is carried out by successive ionic layer adsorption and reaction (SILAR) technique. The synthesized electrode materials are characterized by XRD, XPS, field emission scanning electron microscopy (FE-SEM), Optical, solar cell and electrochemical performances. The results designate that the QDs of CdS and Ag2S have efficiently covered exterior surfaces of TiO2 nanorods assembly. A cautious evaluation between TiO2/CdS and TiO2/CdS/Ag2S sensitized cells tells that CdS and Ag2S synergetically helps to enhance the light harvesting ability. Under AM 1.5G illumination, the photoanodes show an improved power conversion efficiency of 1.87%, in an aqueous polysulfide electrolyte with short-circuit photocurrent density of 7.03 mA cm-2 which is four fold higher than that of a TiO2/CdS system.

Proof-of-principle contraband detection system for nonintrusive inspection

NASA Astrophysics Data System (ADS)

Sredniawski, Joseph J.; Debiak, T.; Kamykowski, E.; Rathke, John E.; Schmor, P.; Milton, Bill; Stanford, G.; Rogers, Joel; Boyd, J.; Brondo, J.

1997-02-01

A proof-of-principle (POP) contraband detection system (CDS), is under construction at Northrop Grumman's Advanced Technology and Development Center. We employ gamma resonance absorption to detect nitrogen or chlorine in explosives and certain forms of illegal drugs. Using tomography, 3D images of the total density and selected element density are generated. These characteristics together may be utilized with considerable confidence in determining if contraband is present in baggage or cargo. The CDS employs a high current DC electrostatic accelerator that provides a beam of proton sat either 1.75 or 1.89 MeV. These high energy particles impinge upon a target coated with 13C or 34S. The resultant resonant gamma rays are preferentially absorbed in either 14N or 35Cl. Because of the penetrating power of the gamma rays, this approach can be utilized for inspection of fully loaded aircraft containers such as the LD3. With proper design for handling baggage and with certain CDS design features not present in the POP, throughputs approaching 2000 bags/hour are estimated. Furthermore, the technology being developed for the CDS accelerator may have other applications such as for Boron Neutron Capture Therapy or Neutron Radiography. Our current program calls for testing of the POP CDS by late 1996. This paper presents the overall design, and characteristics of the CDS POP and the status of the program.

[Prosody, speech input and language acquisition].

PubMed

Jungheim, M; Miller, S; Kühn, D; Ptok, M

2014-04-01

In order to acquire language, children require speech input. The prosody of the speech input plays an important role. In most cultures adults modify their code when communicating with children. Compared to normal speech this code differs especially with regard to prosody. For this review a selective literature search in PubMed and Scopus was performed. Prosodic characteristics are a key feature of spoken language. By analysing prosodic features, children gain knowledge about underlying grammatical structures. Child-directed speech (CDS) is modified in a way that meaningful sequences are highlighted acoustically so that important information can be extracted from the continuous speech flow more easily. CDS is said to enhance the representation of linguistic signs. Taking into consideration what has previously been described in the literature regarding the perception of suprasegmentals, CDS seems to be able to support language acquisition due to the correspondence of prosodic and syntactic units. However, no findings have been reported, stating that the linguistically reduced CDS could hinder first language acquisition.

CdS nanoparticles-enhanced chemiluminescence and determination of baicalin in pharmaceutical preparations.

PubMed

Chen, Xiaolan; Tan, Xinmei; Wang, Jianxiu

2013-01-01

CdS nanoparticles (CdS NPs) of different sizes were synthesized by the citrate reduction method. It was found that CdS NPs could enhance the chemiluminescence (CL) of the luminol-potassium ferricyanide system and baicalin could inhibit CdS NPs-enhanced luminol-potassium ferricyanide CL signals in alkaline solution. Based on this inhibition, a flow-injection CL method was established for determination of baicalin in pharmaceutical preparations and human urine samples. Under optimized conditions, the linear range for determination of baicalin was 5.0 x 10(-6) to 1.0 x 10(-3) g/L. The detection limit at a signal-to-noise ratio of 3 was 1.7 x 10(-6) g/L. CL spectra, UV-visible spectra and transmission electron microscopy (TEM) were used to investigate the CL mechanism. The method described is simple, selective and obviates the need of extensive sample pretreatment. Copyright © 2012 John Wiley & Sons, Ltd.

The preparation and degradation performance of CdS photocatalysts to methyl orange solution.

PubMed

Duan, Limei; Zhao, Weiqiang; Xu, Ling; Chen, Xiaohong; Lita, A; Liu, Zongrui

2013-03-01

In this paper, the CdS samples were prepared using thiourea or sodium sulfide as sulfur source by hydrothermal or solvothermal synthesis method, the results of XRD, TEM and SEM showed all the samples belong to hexagonal CdS nano-material with different morphologies. Using the degradation of methyl orange solution as a model reaction, the photocatalytic performance of different CdS samples was measured, and the samples prepared using thiourea as sulfur source exhibited better photocatalytic activity than those using sodium sulfide as sulfur source. The factors on degradation effect were discussed including the pH value of degradation system and the type of light source. The degradation effect of CdS samples increased with the pH value decreased, and the degradation effect was better when the methyl orange solution was irradiated under sunlight than under 250 W mercury lamp.

Magnetodielectric effect in CdS nanosheets grown within Na-4 mica

NASA Astrophysics Data System (ADS)

Mandal, Amrita; Mitra, Sreemanta; Datta, Anindya; Banerjee, Sourish; Chakravorty, Dipankar

2012-04-01

CdS nanosheets of thickness 0.6 nm were grown within the interlayer spaces of Na-4 mica. Magnetization measurements carried out in the temperature range 2-300 K showed the composites to have weak ferromagnetic-like properties even at room temperature. The saturation magnetization (MS) at room temperature was found to be higher than that reported for CdS nanoparticles. The higher value of MS may be ascribed to the presence of a large number defects in the present CdS system, due to a large surface to volume ratio in the nanosheets as compared to that of CdS nanoparticles. The nanocomposites exhibited a magnetodielectric effect with a dielectric constant change of 5.3% for a magnetic field of 0.5 T. This occurred due to a combination of magnetoresistance and Maxwell-Wagner effect as delineated in the model developed by Catalan.

Harmful impact on presynaptic glutamate and GABA transport by carbon dots synthesized from sulfur-containing carbohydrate precursor.

PubMed

Borisova, Tatiana; Dekaliuk, Mariia; Pozdnyakova, Natalia; Pastukhov, Artem; Dudarenko, Marina; Borysov, Arsenii; Vari, Sandor G; Demchenko, Alexander P

2017-07-01

Carbon nanoparticles that may be potent air pollutants with adverse effects on human health often contain heteroatoms including sulfur. In order to study in detail their effects on different physiological and biochemical processes, artificially produced carbon dots (CDs) with well-controlled composition that allows fluorescence detection may be of great use. Having been prepared from different types of organic precursors, CDs expose different atoms at their surface suggesting a broad variation of functional groups. Recently, we demonstrated neurotoxic properties of CDs synthesized from the amino acid β-alanine, and it is of importance to analyze whether CDs obtained from different precursors and particularly those exposing sulfur atoms induce similar neurotoxic effects. This study focused on synthesis of CDs from the sulfur-containing precursor thiourea-CDs (TU-CDs) with a size less than 10 nm, their characterization, and neuroactivity assessment. Neuroactive properties of TU-CDs were analyzed based on their effects on the key characteristics of glutamatergic and γ-aminobutyric acid (GABA) neurotransmission in isolated rat brain nerve terminals. It was observed that TU-CDs (0.5-1.0 mg/ml) attenuated the initial velocity of Na + -dependent transporter-mediated uptake and accumulation of L-[ 14 C]glutamate and [ 3 H]GABA by nerve terminals in a dose-dependent manner and increased the ambient level of the neurotransmitters. Starting from the concentration of 0.2 mg/ml, TU-CDs evoked a gradual dose-dependent depolarization of the plasma membrane of nerve terminals measured with the cationic potentiometric dye rhodamine 6G. Within the concentration range of 0.1-0.5 mg/ml, TU-CDs caused an "unphysiological" step-like increase in fluorescence intensity of the рН-sensitive fluorescent dye acridine orange accumulated by synaptic vesicles. Therefore, despite different surface properties and fluorescent features of CDs prepared from different starting materials (thiourea and β-alanine), their principal neurotoxic effects are analogous but displayed at a different level of efficiency. Sulfur-containing TU-CDs exhibit lower effects (by ~30%) on glutamate and GABA transport in the nerve terminals in comparison with sulfur-free β-alanine CDs. Our results suggest considering that an uncontrolled presence of carbon-containing particulate matter in the human environment may pose a toxicity risk for the central nervous system.

Cadmium sulfide quantum dots supported on gallium and indium oxide for visible-light-driven hydrogen evolution from water.

PubMed

Pan, Yun-xiang; Zhuang, Huaqiang; Hong, Jindui; Fang, Zheng; Liu, Hai; Liu, Bin; Huang, Yizhong; Xu, Rong

2014-09-01

In this work, CdS quantum dots (QDs) supported on Ga2O3 and In2O3 are applied for visible-light-driven H2 evolution from aqueous solutions that contain lactic acid. With Pt as the cocatalyst, the H2 evolution rates on CdS/Pt/Ga2O3 and CdS/Pt/In2O3 are as high as 995.8 and 1032.2 μmol h(-1), respectively, under visible light (λ>420 nm) with apparent quantum efficiencies of 43.6 and 45.3% obtained at 460 nm, respectively. These are much higher than those on Pt/CdS (108.09 μmol h(-1)), Pt/Ga2O3 (0.12 μmol h(-1)), and Pt/In2O3 (0.05 μmol h(-1)). The photocatalysts have been characterized thoroughly and their band structures and photocurrent responses have been measured. The band alignment between the CdS QDs and In2O3 can lead to interfacial charge separation, which cannot occur between the CdS QDs and Ga2O3. Among the various possible factors that contribute to the high H2 evolution rates on CdS/Pt/oxide, the surface properties of the metal oxides play important roles, which include (i) the anchoring of CdS QDs and Pt nanoparticles for favorable interactions and (ii) the efficient trapping of photogenerated electrons from the CdS QDs because of surface defects (such as oxygen defects) based on photoluminescence and photocurrent studies. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

pXRF analyses of Louise Herreshoff's paintings in relation to CdS and other pigment degradation issues

NASA Astrophysics Data System (ADS)

Uffelman, Erich S.; Hobbs, Patricia A.; Barisas, Derek A. G.; Mass, Jennifer L.

2013-04-01

Portable X-ray Fluorescence Spectrometry (pXRF) was used to survey 33 works in Washington and Lee University's collection of Louise Herreshoff's paintings. This work was done both to support a condition assessment of the paintings and their pigments and to determine which paintings might be appropriate for further study in the context of ongoing key synchrotron research into the degradation mechanisms of cadmium sulfide yellow pigment (CdS).

Abscisic acid has a key role in modulating diverse plant-pathogen interactions

Treesearch

Jun Fan; Lionel Hill; Casey Crooks; Peter Doerner; Chris Lamb

2009-01-01

We isolated an activation-tagged Arabidopsis (Arabidopsis thaliana) line, constitutive disease susceptibility2-1D (cds2-1D), that showed enhanced bacterial growth when challenged with various Pseudomonas syringae strains. Systemic acquired resistance and systemic PATHOGENESIS-RELATED GENE1 induction were also compromised in cds2-1D. The T-DNA insertion adjacent to NINE...

Flow-injection chemiluminescence analysis for sensitive determination of atenolol using cadmium sulfide quantum dots.

PubMed

Khataee, Alireza; Lotfi, Roya; Hasanzadeh, Aliyeh; Iranifam, Mortaza; Joo, Sang Woo

2016-03-15

A sensitive, rapid and simple flow-injection chemiluminescence (CL) system based on the light emitted from KMnO4-cadmium sulfide quantum dots (CdS QDs) reaction in the presence of cetyltrimethylammonium bromide (CTAB) in acidic medium was developed as a CL probe for the sensitive determination of atenolol. Optical and structural features of CdS QDs capped with l-cysteine, which synthesized via hydrothermal approach, were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), and UV-Vis spectroscopy. The CL intensity of KMnO4-CdS QDs-CTAB was remarkably enhanced in the presence of trace level of atenolol. Under optimum experimental conditions, there is a linear relationship between the increase in CL intensity of KMnO4-CdS QDs-CTAB system and atenolol concentration in a range of 0.001 to 4.0 mg L(-1) and 4.0 to 18.0 mg L(-1), with a detection limit (3σ) of 0.0010 mg L(-1). A possible mechanism for KMnO4-CdS QDs-CTAB-atenolol CL reaction is proposed. To prove the practical application of the KMnO4-CdS QDs-CTAB CL method, the method was applied for the determination of atenolol in spiked environmental water samples and commercial pharmaceutical formulation. Furthermore, corona discharge ionization ion mobility spectrometry (CD-IMS) technique was utilized for determination of atenolol. Copyright © 2015 Elsevier B.V. All rights reserved.

Liquidity crisis detection: An application of log-periodic power law structures to default prediction

NASA Astrophysics Data System (ADS)

Wosnitza, Jan Henrik; Denz, Cornelia

2013-09-01

We employ the log-periodic power law (LPPL) to analyze the late-2000 financial crisis from the perspective of critical phenomena. The main purpose of this study is to examine whether LPPL structures in the development of credit default swap (CDS) spreads can be used for default classification. Based on the different triggers of Bear Stearns’ near bankruptcy during the late-2000 financial crisis and Ford’s insolvency in 2009, this study provides a quantitative description of the mechanism behind bank runs. We apply the Johansen-Ledoit-Sornette (JLS) positive feedback model to explain the rise of financial institutions’ CDS spreads during the global financial crisis 2007-2009. This investigation is based on CDS spreads of 40 major banks over the period from June 2007 to April 2009 which includes a significant CDS spread increase. The qualitative data analysis indicates that the CDS spread variations have followed LPPL patterns during the global financial crisis. Furthermore, the univariate classification performances of seven LPPL parameters as default indicators are measured by Mann-Whitney U tests. The present study supports the hypothesis that discrete scale-invariance governs the dynamics of financial markets and suggests the application of new and fast updateable default indicators to capture the buildup of long-range correlations between creditors.

Design of a Basic System of Indicators for Monitoring and Evaluating Spanish Cooperation's Culture and Development Strategy

ERIC Educational Resources Information Center

Coll-Serrano, Vicente; Carrasco-Arroyo, Salvador; Blasco-Blasco, Olga; Vila-Lladosa, Luis

2012-01-01

Objective: This article describes the process implemented in order to define and build up a Basic Monitoring and Evaluation System for Spanish Cooperation's Culture and Development Strategy (CD-S). Research Design: Delphi techniques were used to assess a wide catalogue of indicators for each of the strategic areas included in the CD-S. Afterward,…

Detailed Modeling of Distillation Technologies for Closed-Loop Water Recovery Systems

NASA Technical Reports Server (NTRS)

Allada, Rama Kumar; Lange, Kevin E.; Anderson, Molly S.

2011-01-01

Detailed chemical process simulations are a useful tool in designing and optimizing complex systems and architectures for human life support. Dynamic and steady-state models of these systems help contrast the interactions of various operating parameters and hardware designs, which become extremely useful in trade-study analyses. NASA?s Exploration Life Support technology development project recently made use of such models to compliment a series of tests on different waste water distillation systems. This paper presents efforts to develop chemical process simulations for three technologies: the Cascade Distillation System (CDS), the Vapor Compression Distillation (VCD) system and the Wiped-Film Rotating Disk (WFRD) using the Aspen Custom Modeler and Aspen Plus process simulation tools. The paper discusses system design, modeling details, and modeling results for each technology and presents some comparisons between the model results and recent test data. Following these initial comparisons, some general conclusions and forward work are discussed.

Front air bag nondeployments in frontal crashes fatal to drivers or right-front passengers.

PubMed

Braver, Elisa R; McCartt, Anne T; Sherwood, Christopher P; Zuby, David S; Blanar, Laura; Scerbo, Marge

2010-04-01

Public concern has arisen about the reliability of front air bags because Fatality Analysis Reporting System (FARS) data indicate many nondeployed air bags in fatal frontal crashes. However, the accuracy of air bag deployment, the variable in question, is uncertain. This study aimed to provide more certain estimates of nondeployment incidence in fatal frontal crashes. Fatally injured passenger vehicle drivers and right-front passengers in frontal crashes were identified in two U.S. databases for calendar years 1998-2006 and model years 1994-2006: FARS, a census of police-reported fatal crashes on public roads, and National Automotive Sampling System/Crashworthiness Data System (NASS/CDS), a probability sample of tow-away crashes. NASS/CDS contains subsets of fatal crashes in FARS and collects detailed data using crash investigators. Front air bag deployment coding for front-seat occupant fatalities was compared in FARS and NASS/CDS, and case reviews were conducted. Among FARS frontal deaths with available deployment status (N = 43,169), front air bags were coded as not deployed for 18 percent of front occupants. In comparison, NASS/CDS (N = 628) reported 9 percent (weighted estimate) nondeployment among front occupants killed. Among crashes common to both databases, NASS/CDS reported deployments for 45 percent of front occupant deaths for which FARS had coded nondeployments. Detailed case reviews of NASS/CDS crashes indicated highly accurate coding for deployment status. Based on this case review, 8 percent (weighted estimate) of front occupant deaths in frontal crashes appeared to involve air bag nondeployments; 1-2 percent of front occupant deaths represented potential system failures where deployments would have been expected. Air bag deployments appeared unwarranted in most nondeployments based on crash characteristics. FARS data overstate the magnitude of the problem of air bag deployment failures; steps should be taken to improve coding. There are inherent uncertainties in judgments about whether or not air bags would be expected to deploy in some crashes. Continued monitoring of air bag performance is warranted.

Health Care Expenditures and Utilization for Children With Noncomplex Chronic Disease.

PubMed

Hoefgen, Erik R; Andrews, Annie L; Richardson, Troy; Hall, Matthew; Neff, John M; Macy, Michelle L; Bettenhausen, Jessica L; Shah, Samir S; Auger, Katherine A

2017-09-01

Pediatric health care expenditures and use vary by level of complexity and chronic illness. We sought to determine expenditures and use for children with noncomplex chronic diseases (NC-CDs). We performed a retrospective, cross-sectional analysis of Medicaid enrollees (ages 0-18 years) from January 1, 2012, through December 31, 2013, using administrative claims (the Truven MarketScan Medicaid Database). Patients were categorized by chronicity of illness by using 3M Health Information System's Clinical Risk Groups (CRGs) as follows: without chronic diseases (WO-CDs) (CRG 1-2), NC-CDs (CRG 3-5), and complex chronic diseases (C-CDs) (CRG 6-9). Primary outcomes were medical expenditures, including total annualized population expenditure and per-member per-year expenditure (PMPY). Secondary outcomes included the number of health care encounters over the 2-year period. There were 2 424 946 children who met inclusion criteria, 53% were WO-CD; 36% had an NC-CD; and 11% had a C-CD. Children with NC-CDs accounted for 33% ($2801 PMPY) of the annual spending compared with 20% ($1151 PMPY) accounted for by children WO-CDs and 47% ($12 569 PMPY) by children with C-CDs. The median outpatient visit count by group over the 2-year period was 15 (interquartile range [IQR] 10-25) for NC-CD, 8 (IQR 5-13) WO-CD, and 34 (IQR 19-72) for C-CD. Children with NC-CDs accounted for 33% of pediatric Medicaid expenditures and have significantly higher PMPY and aggregate annual expenditures than children WO-CDs. The annual aggregate expenditures of the NC-CD group represent a significant societal cost because of the high volume of children, extrapolated to ∼$34.9 billion annually in national Medicaid expenditures. Copyright © 2017 by the American Academy of Pediatrics.

Impact of Computerized Decision Support on Blood Pressure Management and Control: A Randomized Controlled Trial

PubMed Central

Sequist, Thomas D.; Ayanian, John Z.; Shaykevich, Shimon; Fairchild, David G.; Orav, E. John; Bates, David W.

2008-01-01

BACKGROUND We conducted a cluster randomized controlled trial to examine the effectiveness of computerized decision support (CDS) designed to improve hypertension care and outcomes in a racially diverse sample of primary care patients. METHODS We randomized 2,027 adult patients receiving hypertension care in 14 primary care practices to either 18 months of their physicians receiving CDS for each hypertensive patient or to usual care without computerized support for the control group. We assessed prescribing of guideline-recommended drug therapy and levels of blood pressure control for patients in each group and examined if the effects of the intervention differed by patients’ race/ethnicity using interaction terms. MEASUREMENTS AND MAIN RESULTS Rates of blood pressure control were 42% at baseline and 46% at the outcome visit with no significant differences between groups. After adjustment for patients’ demographic and clinical characteristics, number of prior visits, and levels of baseline blood pressure control, there were no differences between intervention groups in the odds of outcome blood pressure control. The use of CDS to providers significantly improved Joint National Committee (JNC) guideline adherent medication prescribing compared to usual care (7% versus 5%, P < 0.001); the effects of the intervention remained after multivariable adjustment (odds ratio [OR] 1.39 [CI, 1.13–1.72]) and the effects of the intervention did not differ by patients’ race and ethnicity. CONCLUSIONS CDS improved appropriate medication prescribing with no improvement in disparities in care and overall blood pressure control. Future work focusing on improvement of these interventions and the study of other practical interventions to reduce disparities in hypertension-related outcomes is needed. PMID:18373141

NCAR Earth Observing Laboratory's Data Tracking System

NASA Astrophysics Data System (ADS)

Cully, L. E.; Williams, S. F.

2014-12-01

The NCAR Earth Observing Laboratory (EOL) maintains an extensive collection of complex, multi-disciplinary datasets from national and international, current and historical projects accessible through field project web pages (https://www.eol.ucar.edu/all-field-projects-and-deployments). Data orders are processed through the EOL Metadata Database and Cyberinfrastructure (EMDAC) system. Behind the scenes is the institutionally created EOL Computing, Data, and Software/Data Management Group (CDS/DMG) Data Tracking System (DTS) tool. The DTS is used to track the complete life cycle (from ingest to long term stewardship) of the data, metadata, and provenance for hundreds of projects and thousands of data sets. The DTS is an EOL internal only tool which consists of three subsystems: Data Loading Notes (DLN), Processing Inventory Tool (IVEN), and Project Metrics (STATS). The DLN is used to track and maintain every dataset that comes to the CDS/DMG. The DLN captures general information such as title, physical locations, responsible parties, high level issues, and correspondence. When the CDS/DMG processes a data set, IVEN is used to track the processing status while collecting sufficient information to ensure reproducibility. This includes detailed "How To" documentation, processing software (with direct links to the EOL Subversion software repository), and descriptions of issues and resolutions. The STATS subsystem generates current project metrics such as archive size, data set order counts, "Top 10" most ordered data sets, and general information on who has ordered these data. The DTS was developed over many years to meet the specific needs of the CDS/DMG, and it has been successfully used to coordinate field project data management efforts for the past 15 years. This paper will describe the EOL CDS/DMG Data Tracking System including its basic functionality, the provenance maintained within the system, lessons learned, potential improvements, and future developments.

Back to the Bedside: Developing a Bedside Aid for Concussion and Brain Injury Decisions in the Emergency Department

PubMed Central

Melnick, Edward R.; Lopez, Kevin; Hess, Erik P.; Abujarad, Fuad; Brandt, Cynthia A.; Shiffman, Richard N.; Post, Lori A.

2015-01-01

Context: Current information-rich electronic health record (EHR) interfaces require large, high-resolution screens running on desktop computers. This interface compromises the provider’s already limited time at the bedside by physically separating the patient from the doctor. The case study presented here describes a patient-centered clinical decision support (CDS) design process that aims to bring the physician back to the bedside by integrating a patient decision aid with CDS for shared use by the patient and provider on a touchscreen tablet computer for deciding whether or not to obtain a CT scan for minor head injury in the emergency department, a clinical scenario that could benefit from CDS but has failed previous implementation attempts. Case Description: This case study follows the user-centered design (UCD) approach to build a bedside aid that is useful and usable, and that promotes shared decision-making between patients and their providers using a tablet computer at the bedside. The patient-centered decision support design process focuses on the prototype build using agile software development, but also describes the following: (1) the requirement gathering phase including triangulated qualitative research (focus groups and cognitive task analysis) to understand current challenges, (2) features for patient education, the physician, and shared decision-making, (3) system architecture and technical requirements, and (4) future plans for formative usability testing and field testing. Lessons Learned: We share specific lessons learned and general recommendations from critical insights gained in the patient-centered decision support design process about early stakeholder engagement, EHR integration, external expert feedback, challenges to two users on a single device, project management, and accessibility. Conclusions: Successful implementation of this tool will require seamless integration into the provider’s workflow. This protocol can create an effective interface for shared decision-making and safe resource reduction at the bedside in the austere and dynamic clinical environment of the ED and is generalizable for these purposes in other clinical environments as well. PMID:26290885

Back to the Bedside: Developing a Bedside Aid for Concussion and Brain Injury Decisions in the Emergency Department.

PubMed

Melnick, Edward R; Lopez, Kevin; Hess, Erik P; Abujarad, Fuad; Brandt, Cynthia A; Shiffman, Richard N; Post, Lori A

2015-01-01

Current information-rich electronic health record (EHR) interfaces require large, high-resolution screens running on desktop computers. This interface compromises the provider's already limited time at the bedside by physically separating the patient from the doctor. The case study presented here describes a patient-centered clinical decision support (CDS) design process that aims to bring the physician back to the bedside by integrating a patient decision aid with CDS for shared use by the patient and provider on a touchscreen tablet computer for deciding whether or not to obtain a CT scan for minor head injury in the emergency department, a clinical scenario that could benefit from CDS but has failed previous implementation attempts. This case study follows the user-centered design (UCD) approach to build a bedside aid that is useful and usable, and that promotes shared decision-making between patients and their providers using a tablet computer at the bedside. The patient-centered decision support design process focuses on the prototype build using agile software development, but also describes the following: (1) the requirement gathering phase including triangulated qualitative research (focus groups and cognitive task analysis) to understand current challenges, (2) features for patient education, the physician, and shared decision-making, (3) system architecture and technical requirements, and (4) future plans for formative usability testing and field testing. We share specific lessons learned and general recommendations from critical insights gained in the patient-centered decision support design process about early stakeholder engagement, EHR integration, external expert feedback, challenges to two users on a single device, project management, and accessibility. Successful implementation of this tool will require seamless integration into the provider's workflow. This protocol can create an effective interface for shared decision-making and safe resource reduction at the bedside in the austere and dynamic clinical environment of the ED and is generalizable for these purposes in other clinical environments as well.

PIP-II Cryogenic System and the evolution of Superfluid Helium Cryogenic Plant Specifications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chakravarty, Anindya; Rane, Tejas; Klebaner, Arkadiy

2017-07-06

The PIP-II cryogenic system consists of a Superfluid Helium Cryogenic Plant (SHCP) and a Cryogenic Distribution System (CDS) connecting the SHCP to the Superconducting (SC) Linac consisting of 25 cryomodules. The dynamic heat load of the SC cavities for continuous wave (CW) as well as pulsed mode of operation has been listed out. The static heat loads of the cavities along with the CDS have also been discussed. Simulation study has been carried out to compute the supercritical helium (SHe) flow requirements for each cryomodule. Comparison between the flow requirements of the cryomodules for the CW and pulsed modes ofmore » operation have also been made. From the total computed heat load and pressure drop values in the CDS, the basic specifications for the SHCP, required for cooling the SC Linac, have evolved.« less

Fluorescent Carbon Dots Derived from Maillard Reaction Products: Their Properties, Biodistribution, Cytotoxicity, and Antioxidant Activity.

PubMed

Li, Dongmei; Na, Xiaokang; Wang, Haitao; Xie, Yisha; Cong, Shuang; Song, Yukun; Xu, Xianbing; Zhu, Bei-Wei; Tan, Mingqian

2018-02-14

Food-borne nanoparticles have received great attention because of their unique physicochemical properties and potential health risk. In this study, carbon dots (CDs) formed during one of the most important chemical reactions in the food processing field, the Maillard reaction from the model system including glucose and lysine, were investigated. The CDs purified from Maillard reaction products emitted a strong blue fluorescence under ultraviolet light with a fluorescent quantum yield of 16.30%. In addition, they were roughly spherical, with sizes of around 4.3 nm, and mainly composed of carbon, oxygen, hydrogen, and nitrogen. Their surface groups such as hydroxyl, amino, and carboxyl groups were found to possibly enable CDs to scavenge DPPH and hydroxyl radicals. Furthermore, the cytotoxicity assessment of CDs showed that they could readily enter HepG2 cells while causing negligible cell death at low concentration. However, high CDs concentrations were highly cytotoxic and led to cell death via interference of the glycolytic pathway.

Feasibility of using algorithm-based clinical decision support for symptom assessment and management in lung cancer.

PubMed

Cooley, Mary E; Blonquist, Traci M; Catalano, Paul J; Lobach, David F; Halpenny, Barbara; McCorkle, Ruth; Johns, Ellis B; Braun, Ilana M; Rabin, Michael S; Mataoui, Fatma Zohra; Finn, Kathleen; Berry, Donna L; Abrahm, Janet L

2015-01-01

Distressing symptoms interfere with the quality of life in patients with lung cancer. Algorithm-based clinical decision support (CDS) to improve evidence-based management of isolated symptoms seems promising, but no reports yet address multiple symptoms. This study examined the feasibility of CDS for a Symptom Assessment and Management Intervention targeting common symptoms in patients with lung cancer (SAMI-L) in ambulatory oncology. The study objectives were to evaluate completion and delivery rates of the SAMI-L report and clinician adherence to the algorithm-based recommendations. Patients completed a web-based symptom assessment and SAMI-L created tailored recommendations for symptom management. Completion of assessments and delivery of reports were recorded. Medical record review assessed clinician adherence to recommendations. Feasibility was defined as 75% or higher report completion and delivery rates and 80% or higher clinician adherence to recommendations. Descriptive statistics and generalized estimating equations were used for data analyses. Symptom assessment completion was 84% (95% CI=81-87%). Delivery of completed reports was 90% (95% CI=86-93%). Depression (36%), pain (30%), and fatigue (18%) occurred most frequently, followed by anxiety (11%) and dyspnea (6%). On average, overall recommendation adherence was 57% (95% CI=52-62%) and was not dependent on the number of recommendations (P=0.45). Adherence was higher for anxiety (66%; 95% CI=55-77%), depression (64%; 95% CI=56-71%), pain (62%; 95% CI=52-72%), and dyspnea (51%; 95% CI=38-64%) than for fatigue (38%; 95% CI=28-47%). The CDS systems, such as SAMI-L, have the potential to fill a gap in promoting evidence-based care. Copyright © 2015 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Clinical Decision Support Improves Initial Dosing and Monitoring of Tobramycin and Amikacin

PubMed Central

Cox, Zachary L.; Nelsen, Cori L.; Waitman, Lemuel R.; McCoy, Jacob A.; Peterson, Josh F.

2010-01-01

Purpose Clinical decision support (CDS) systems could be valuable tools in reducing aminoglycoside prescribing errors. We evaluated the impact of CDS on initial dosing, interval, and pharmacokinetic outcomes of amikacin and tobramycin therapy. Methods A complex CDS advisor to provide guidance on initial dosing and monitoring, using both traditional and extended interval dosing strategies, was integrated into computerized provider order entry (CPOE) and compared to a control group which featured close pharmacy monitoring of all aminoglycoside orders. A random sample of 118 patients from an academic, tertiary care medical center prescribed amikacin and tobramycin prior to advisor implementation was compared to 98 patients admitted following advisor implementation. Primary outcome was an initial dose within 10% of a dose calculated to be adherent to published dose guidelines. Secondary outcomes were a guideline-adherent interval, trough and peak concentrations in goal range, and incidence of nephrotoxicity. Results Of 216 patients studied, 97 were prescribed amikacin and 119 were prescribed tobramycin. The primary outcome of initial dosing consistent with guideline-based care increased from 40% in the pre-advisor arm to 80% in the post-advisor arm (p<0.001), with a number needed to treat of 3 patients to prevent one incorrect dose. Correct initial interval based on renal function also increased from 63% to 87% (p<0.001). The changes in initial dosing and interval resulted in an increase of trough concentrations in the goal range from 59% pre-advisor to 89% post-advisor implementation (p=0.0004). There was no significant difference in peak concentrations in goal range or incidence of nephrotoxicity (25% vs. 17%, p=0.2). Conclusion An advisor for aminoglycoside dosing and monitoring integrated into CPOE significantly improves initial dosing, selection of interval, and trough concentrations at goal compared to unassisted physician dosing. PMID:21411805

CDS, UX, and System Redesign - Promising Techniques and Tools to Bridge the Evidence Gap.

PubMed

McGinn, Thomas

2015-01-01

In this special issue of eGEMs, we explore the struggles related to bringing evidence into day-to-day practice, what I define as the "evidence gap." We are all aware of high quality evidence in the form of guidelines, randomized clinical trials for treatments and diagnostic tests, and clinical prediction rules, which are all readily available online. We also know that electronic health records (EHRs) are now ubiquitous in health care and in most practices across the country. How we marry this high quality evidence and the practice of medicine through effective decision support is a major challenge. All of the articles in this issue explore, in some fashion, CDS systems and how we can best bring providers and their work environment to the evidence. We are at the very early stages of the science of usability. Much more research and funding is needed in this area if we hope to improve the dissemination and implementation of evidence in practice. While the featured examples, techniques, and tools in the special issue are a promising start to improving usability and CDS, many of the papers highlight current gaps in knowledge and a great need for generalizable approaches. The great promise is for "learning" approaches to generate new evidence and to integrate this evidence in reliable, patient-centered ways at scale using new technology. Closing the evidence gap is a real possibility, but only if the community works together to innovate and invest in research on the best ways to disseminate, communicate, and implement evidence in practice.

Derivatives and credit contagion in interconnected networks

NASA Astrophysics Data System (ADS)

Heise, S.; Kühn, R.

2012-04-01

The importance of adequately modeling credit risk has once again been highlighted in the recent financial crisis. Defaults tend to cluster around times of economic stress due to poor macro-economic conditions, but also by directly triggering each other through contagion. Although credit default swaps have radically altered the dynamics of contagion for more than a decade, models quantifying their impact on systemic risk are still missing. Here, we examine contagion through credit default swaps in a stylized economic network of corporates and financial institutions. We analyse such a system using a stochastic setting, which allows us to exploit limit theorems to exactly solve the contagion dynamics for the entire system. Our analysis shows that, by creating additional contagion channels, CDS can actually lead to greater instability of the entire network in times of economic stress. This is particularly pronounced when CDS are used by banks to expand their loan books (arguing that CDS would offload the additional risks from their balance sheets). Thus, even with complete hedging through CDS, a significant loan book expansion can lead to considerably enhanced probabilities for the occurrence of very large losses and very high default rates in the system. Our approach adds a new dimension to research on credit contagion, and could feed into a rational underpinning of an improved regulatory framework for credit derivatives.

Cell Nucleus-Targeting Zwitterionic Carbon Dots.

PubMed

Jung, Yun Kyung; Shin, Eeseul; Kim, Byeong-Su

2015-12-22

An innovative nucleus-targeting zwitterionic carbon dot (CD) vehicle has been developed for anticancer drug delivery and optical monitoring. The zwitterionic functional groups of the CDs introduced by a simple one-step synthesis using β-alanine as a passivating and zwitterionic ligand allow cytoplasmic uptake and subsequent nuclear translocation of the CDs. Moreover, multicolor fluorescence improves the accuracy of the CDs as an optical code. The CD-based drug delivery system constructed by non-covalent grafting of doxorubicin, exhibits superior antitumor efficacy owing to enhanced nuclear delivery in vitro and tumor accumulation in vivo, resulting in highly effective tumor growth inhibition. Since the zwitterionic CDs are highly biocompatible and effectively translocated into the nucleus, it provides a compelling solution to a multifunctional nanoparticle for substantially enhanced nuclear uptake of drugs and optical monitoring of translocation.

Cell Nucleus-Targeting Zwitterionic Carbon Dots

PubMed Central

Jung, Yun Kyung; Shin, Eeseul; Kim, Byeong-Su

2015-01-01

An innovative nucleus-targeting zwitterionic carbon dot (CD) vehicle has been developed for anticancer drug delivery and optical monitoring. The zwitterionic functional groups of the CDs introduced by a simple one-step synthesis using β-alanine as a passivating and zwitterionic ligand allow cytoplasmic uptake and subsequent nuclear translocation of the CDs. Moreover, multicolor fluorescence improves the accuracy of the CDs as an optical code. The CD-based drug delivery system constructed by non-covalent grafting of doxorubicin, exhibits superior antitumor efficacy owing to enhanced nuclear delivery in vitro and tumor accumulation in vivo, resulting in highly effective tumor growth inhibition. Since the zwitterionic CDs are highly biocompatible and effectively translocated into the nucleus, it provides a compelling solution to a multifunctional nanoparticle for substantially enhanced nuclear uptake of drugs and optical monitoring of translocation. PMID:26689549

US Gateway to SIMBAD Astronomical Database

NASA Technical Reports Server (NTRS)

Eichhorn, G.; Oliversen, R. (Technical Monitor)

1999-01-01

During the last year the US SIMBAD Gateway Project continued to provide services like user registration to the US users of the SIMBAD database in France. Currently there are over 3400 US users registered. We also provide user support by answering questions from users and handling requests for lost passwords when still necessary. We have implemented in cooperation with the CDS SIMBAD project access to the SIMBAD database for US users on an Internet address basis. This allows most US users to access SIMBAD without having to enter passwords. We have maintained the mirror copy of the SIMBAD database on a server at SAO. This has allowed much faster access for the US users. We also supported a demonstration of the SIMBAD database at the meeting of the American Astronomical Society in January. We shipped computer equipment to the meeting and provided support for the demonstration activities at the SIMBAD booth. We continued to improve the cross-linking between the SIMBAD project and the Astrophysics Data System. This cross-linking between these systems is very much appreciated by the users of both the SIMBAD database and the ADS Abstract Service. The mirror of the SIMBAD database at SAO makes this connection faster for the US astronomers. We exchange information between the ADS and SIMBAD on a daily basis. The close cooperation between the CDS in Strasbourg and SAO, facilitated by this project, is an important part of the astronomy-wide digital library initiative called Urania. It has proven to be a model in how different data centers can collaborate and enhance the value of their products by linking with other data centers.

Use of real-time tools to support field operations of NSF's Lower Atmosphere Observing Facilities

NASA Astrophysics Data System (ADS)

Daniels, M.; Stossmeister, G.; Johnson, E.; Martin, C.; Webster, C.; Dixon, M.; Maclean, G.

2012-12-01

NCAR's Earth Observing Laboratory (EOL) operates Lower Atmosphere Observing Facilities (LAOF) for the scientific community, under sponsorship of the National Science Foundation. In order to obtain the highest quality dataset during field campaigns, real-time decision-making critically depends on the availability of timely data and reliable communications between field operations staff and instrument operators. EOL incorporates the latest technologies to monitor the health of instrumentation, facilitate remote operations of instrumentation and keep project participants abreast of changing conditions in the field. As the availability of bandwidth on mobile communication networks and the capabilities of their associated devices (smart phone, tablets, etc.) improved, so has the ability of researchers to respond to rapidly changing conditions and coordinate ever more detailed measurements from multiple remote fixed, portable and airborne platforms. This presentation will describe several new tools that EOL is making available to project investigators and how these tools are being used in a mobile computing environment to support enhanced data collection during field campaigns. LAOF platforms such as radars, aircraft, sondes, balloons and surface stations all rely on displays of real-time data for their operations. Data from sondes are ingested into the Global Telecommunications System (GTS) for assimilation into regional forecasting models that help guide project operations. Since many of EOL's projects occur around the globe and at the same time instrument complexity has increased, automated monitoring of instrumentation platforms and systems has become essential. Tools are being developed to allow remote instrument control of our suite of observing systems where feasible. The Computing, Data and Software (CDS) Facility of EOL develops and supports a Field Catalog used in field campaigns for nearly two decades. Today, the Field Catalog serves as a hub for the collection and browsing of field research products, related operational and forecast imagery, project documentation as well as tools for real-time decision-making, communication, mission planning and post analysis. Incorporation of new capabilities into the Field Catalog to support the mobile computing environment and devices has led to the development of new tools which will be described. EOL/CDS has also developed a customized Internet Relay Chat (IRC) chat system to enable communication between all project participants distributed across various land-based, shipboard and airborne remote sites. The CDS chat system has incorporated aspects of fault tolerance in order to handle intermittent communications links. NOAA and NASA have used this chat system for their field missions as well. These new tools were recently deployed in support of the Deep Convective Clouds and Chemistry (DC3) field campaign that took place May - June 2012 in the Central United States. This presentation will show examples of these real-time tools from recent projects. We will also describe some of the challenges, problems and surprises, as well as improvements that have been made to the tools. The capabilities of this system continue to advance, taking advantage of new technology and guided by our experience and feedback from users participating in field campaigns.

Cascading electron and hole transfer dynamics in a CdS/CdTe core-shell sensitized with bromo-pyrogallol red (Br-PGR): slow charge recombination in type II regime.

PubMed

Maity, Partha; Debnath, Tushar; Chopra, Uday; Ghosh, Hirendra Nath

2015-02-14

Ultrafast cascading hole and electron transfer dynamics have been demonstrated in a CdS/CdTe type II core-shell sensitized with Br-PGR using transient absorption spectroscopy and the charge recombination dynamics have been compared with those of CdS/Br-PGR composite materials. Steady state optical absorption studies suggest that Br-PGR forms strong charge transfer (CT) complexes with both the CdS QD and CdS/CdTe core-shell. Hole transfer from the photo-excited QD and QD core-shell to Br-PGR was confirmed by both steady state and time-resolved emission spectroscopy. Charge separation was also confirmed by detecting electrons in the conduction band of the QD and the cation radical of Br-PGR as measured from femtosecond transient absorption spectroscopy. Charge separation in the CdS/Br-PGR composite materials was found to take place in three different pathways, by transferring the photo-excited hole of CdS to Br-PGR, electron injection from the photo-excited Br-PGR to the CdS QD, and direct electron transfer from the HOMO of Br-PGR to the conduction band of the CdS QD. However, in the CdS/CdTe/Br-PGR system hole transfer from the photo-excited CdS to Br-PGR and electron injection from the photo-excited Br-PGR to CdS take place after cascading through the CdTe shell QD. Charge separation also takes place via direct electron transfer from the Br-PGR HOMO to the conduction band of CdS/CdTe. Charge recombination (CR) dynamics between the electron in the conduction band of the CdS QD and the Br-PGR cation radical were determined by monitoring the bleach recovery kinetics. The CR dynamics were found to be much slower in the CdS/CdTe/Br-PGR system than in the CdS/Br-PGR system. The formation of the strong CT complex and the separation of charges cascading through the CdTe shell help to slow down charge recombination in the type II regime.

Advancing clinical decision support using lessons from outside of healthcare: an interdisciplinary systematic review

PubMed Central

2012-01-01

Background Greater use of computerized decision support (DS) systems could address continuing safety and quality problems in healthcare, but the healthcare field has struggled to implement DS technology. This study surveys DS experience across multiple non-healthcare disciplines for new insights that are generalizable to healthcare provider decisions. In particular, it sought design principles and lessons learned from the other disciplines that could inform efforts to accelerate the adoption of clinical decision support (CDS). Methods Our systematic review drew broadly from non-healthcare databases in the basic sciences, social sciences, humanities, engineering, business, and defense: PsychINFO, BusinessSource Premier, Social Sciences Abstracts, Web of Science, and Defense Technical Information Center. Because our interest was in DS that could apply to clinical decisions, we selected articles that (1) provided a review, overview, discussion of lessons learned, or an evaluation of design or implementation aspects of DS within a non-healthcare discipline and (2) involved an element of human judgment at the individual level, as opposed to decisions that can be fully automated or that are made at the organizational level. Results Clinical decisions share some similarities with decisions made by military commanders, business managers, and other leaders: they involve assessing new situations and choosing courses of action with major consequences, under time pressure, and with incomplete information. We identified seven high-level DS system design features from the non-healthcare literature that could be applied to CDS: providing broad, system-level perspectives; customizing interfaces to specific users and roles; making the DS reasoning transparent; presenting data effectively; generating multiple scenarios covering disparate outcomes (e.g., effective; effective with side effects; ineffective); allowing for contingent adaptations; and facilitating collaboration. The article provides examples of each feature. The DS literature also emphasizes the importance of organizational culture and training in implementation success. The literature contrasts “rational-analytic” vs. “naturalistic-intuitive” decision-making styles, but the best approach is often a balanced approach that combines both styles. It is also important for DS systems to enable exploration of multiple assumptions, and incorporation of new information in response to changing circumstances. Conclusions Complex, high-level decision-making has common features across disciplines as seemingly disparate as defense, business, and healthcare. National efforts to advance the health information technology agenda through broader CDS adoption could benefit by applying the DS principles identified in this review. PMID:22900537

Defect measurement and analysis of JPL ground software: a case study

NASA Technical Reports Server (NTRS)

Powell, John D.; Spagnuolo, John N., Jr.

2004-01-01

Ground software systems at JPL must meet high assurance standards while remaining on schedule due to relatively immovable launch dates for spacecraft that will be controlled by such systems. Toward this end, the Software Quality Improvement (SQI) project's Measurement and Benchmarking (M&B) team is collecting and analyzing defect data of JPL ground system software projects to build software defect prediction models. The aim of these models is to improve predictability with regard to software quality activities. Predictive models will quantitatively define typical trends for JPL ground systems as well as Critical Discriminators (CDs) to provide explanations for atypical deviations from the norm at JPL. CDs are software characteristics that can be estimated or foreseen early in a software project's planning. Thus, these CDs will assist in planning for the predicted degree to which software quality activities for a project are likely to deviation from the normal JPL ground system based on pasted experience across the lab.

Knowledge Integration and Use-Case Analysis for a Customized Drug-Drug Interaction CDS Service

NASA Astrophysics Data System (ADS)

Kam, Hye Jin; Park, Man Young; Kim, Woojae; Yoon, Duk Yong; Ahn, Eun Kyoung; Park, Rae Woong

Clinical decision support systems (CDSSs) are thought to reduce adverse drug events (ADEs) by monitoring drug-drug interactions(DDIs). However, clinically improper or excessive alerts can result in high alert overrides. A tailored CDS service, which is appropriate for clinicians and their ordering situations, is required to increase alert acceptance. In this study, we conducted a 12-week pilot project adopting a tailed CDSS at an emergency department. The new CDSS was conducted via a stepwise integration of additional new rules. The alert status with changes in acceptance rate was analyzed. The most frequent DDI alerts were related to prescriptions of anti-inflammatory drugs. The percentages of alert overrides for each stage were 98.0%, 96.0%, 96.9%, and 98.1%, respectively. 91.5% of overridden alerts were related to discharge medications. To reduce the potential hazards of ADEs, the development of an effective customized DDI CDSS is required, via in-depth analysis on alert patterns and overridden reasons.

PIP-II Cryogenic System and the Evolution of Superfluid Helium Cryogenic Plant Specifications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chakravarty, Anindya; Rane, Tejas; Klebaner, Arkadiy

2017-01-01

PIP-II cryogenic system: Superfluid Helium Cryogenic Plant (SHCP) and Cryogenic Distribution System (CDS) connecting the SHCP and the SC Linac (25 cryomodules) PIP-II Cryogenic System Static and dynamic heat loads for the SC Linac and static load of CDS listed out Simulation study carried out to compute SHe flow requirements for each cryomodule Comparison between the flow requirements of the cryomodules for the CW and pulsed modes of operation presented From computed heat load and pressure drop values, SHCP basic specifications evolved.

Extreme Ultraviolet Imaging Telescope (EIT)

NASA Technical Reports Server (NTRS)

Lemen, J. R.; Freeland, S. L.

1997-01-01

Efforts concentrated on development and implementation of the SolarSoft (SSW) data analysis system. From an EIT analysis perspective, this system was designed to facilitate efficient reuse and conversion of software developed for Yohkoh/SXT and to take advantage of a large existing body of software developed by the SDAC, Yohkoh, and SOHO instrument teams. Another strong motivation for this system was to provide an EIT analysis environment which permits coordinated analysis of EIT data in conjunction with data from important supporting instruments, including Yohkoh/SXT and the other SOHO coronal instruments; CDS, SUMER, and LASCO. In addition, the SSW system will support coordinated EIT/TRACE analysis (by design) when TRACE data is available; TRACE launch is currently planned for March 1998. Working with Jeff Newmark, the Chianti software package (K.P. Dere et al) and UV /EUV data base was fully integrated into the SSW system to facilitate EIT temperature and emission analysis.

A Study of the NASS-CDS System for Injury/Fatality Rates of Occupants in Various Restraints and A Discussion of Alternative Presentation Methods

PubMed Central

Stucki, Sheldon Lee; Biss, David J.

2000-01-01

An analysis was performed using the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) database to compare the injury/fatality rates of variously restrained driver occupants as compared to unrestrained driver occupants in the total database of drivers/frontals, and also by Delta-V. A structured search of the NASS-CDS was done using the SAS® statistical analysis software to extract the data for this analysis and the SUDAAN software package was used to arrive at statistical significance indicators. In addition, this paper goes on to investigate different methods for presenting results of accident database searches including significance results; a risk versus Delta-V format for specific exposures; and, a percent cumulative injury versus Delta-V format to characterize injury trends. These alternative analysis presentation methods are then discussed by example using the present study results. PMID:11558105

Making cognitive decision support work: Facilitating adoption, knowledge and behavior change through QI.

PubMed

Weir, Charlene; Brunker, Cherie; Butler, Jorie; Supiano, Mark A

2017-07-01

This paper evaluates the role of facilitation in the successful implementation of Computerized Decision Support (CDS). Facilitation processes include education, specialized computerized decision support, and work process reengineering. These techniques, as well as modeling and feedback enhance self-efficacy, which we propose is one of the factors that mediate the effectiveness of any CDS. In this study, outpatient clinics implemented quality improvement (QI) projects focused on improving geriatric care. Quality Improvement is the systematic process of improving quality through continuous measurement and targeted actions. The program, entitled "Advancing Geriatric Education through Quality Improvement" (AGE QI), consisted of a 6-month, QI based, intervention: (1) 2h didactic session, (2) 1h QI planning session, (3) computerized decision support design and implementation, (4) QI facilitation activities, (5) outcome feedback, and (6) 20h of CME. Specifically, we examined the impact of the QI based program on clinician's perceived self-efficacy in caring for older adults and the relationship of implementation support and facilitation on perceived success. The intervention was implemented at 3 institutions, 27 community healthcare system clinics, and 134 providers. This study reports the results of pre/post surveys for the forty-nine clinicians who completed the full CME program. Self-efficacy ratings for specific clinical behaviors related to care of older adults were assessed using a Likert based instrument. Self-ratings of efficacy improved across the following domains (depression, falls, end-of-life, functional status and medication management) and specifically in QI targeted domains and were associated with overall clinic improvements. Published by Elsevier Inc.

Two-dimensional TiO2-based nanosheets co-modified by surface-enriched carbon dots and Gd2O3 nanoparticles for efficient visible-light-driven photocatalysis

NASA Astrophysics Data System (ADS)

Lu, Dingze; Fang, Pengfei; Ding, Junqian; Yang, Minchen; Cao, Yufei; Zhou, Yawei; Peng, Kui; Kondamareddy, Kiran Kumar; Liu, Min

2017-02-01

Two-dimensional TiO2-based nanosheets (TNSs) co-modified by surface-enriched carbon dots (CDs) and Gd2O3 nanoparticles: (Gd-C-TNSs), capable of exhibiting visible-light-driven photo catalysis were synthesized using a two-pot hydrothermal route. The samples had a sheet-like structure, thickness of approximately 3.6 nm, large specific surface area of 240-350 cm2/g. The CDs (2-3 nm) and Gd2O3 nanoparticles (1-2 nm) were highly dispersed over the surface of the nanosheets. The co-modification by Gd2O3 nanoparticles and CDs influenced the crystallinity, crystal structure, and surface area of the TNSs, and improved the visible-light absorption. Surface photocurrent and fluorescence spectral studies revealed that the photo-generated charge carrier separation efficiency could be improved by an appropriate amount of modification. A very high efficiency was obtained using 0.5 at% Gd/Ti and 3.0 g/L of CDs. The visible-light-induced photocatalytic activity is enhanced under the isolated Cr(VI) system, isolated Rhodamin B (RhB) system, and the synergism between RhB degradation and Cr(VI) reduction for the Gd-C-TNSs photocatalysts. Initially, the photocatalytic activity gradually increased with an increase in the amount of CDs, and then decreased after attaining a maximum, in the case where 0.5 at% Gd/Ti and 3.0 g/L of CDs were used. The enhancement in the photocatalytic activity was attributed to the synergetic effect of the Gd2O3 nanoparticles, TNSs, and CDs in the Gd-C-TNSs composites. The effect led to a fast separation and slow recombination of photo-induced electron-hole pairs. An alternate mechanism for enhanced visible-light photocatalytic activity was also considered.

Transition Metal Nanomaterials by Bacterial Precipitation: Synthesis and Characterization of Cadmium Sulfide Quantum Dots

NASA Astrophysics Data System (ADS)

Marusak, Katherine Elizabeth

We present a new method to fabricate semiconducting, transition metal nanoparticles (NPs) with tunable bandgap energies using engineered Escherichia coli. These bacteria overexpress the Treponema denticola cysteine desulfhydrase gene to facilitate precipitation of cadmium sulfide (CdS) NPs. Multiple characterization techniques reveal that the bacterially precipitated NPs are agglomerates of mostly quantum dots, with diameters that can range from 3 to 15 nm, embedded in a carbon-rich matrix. Notably, the measured photoelectrochemical current generated by these NPs is comparable to values reported in the literature and higher than that of synthesized chemical bath deposited CdS NPs. We showed that we can manipulate the bandgap energy of the NPs by controlling their size through varying the precursor concentrations. Our calculated bandgap energies ranged between 2.67 eV (i.e., quantum confined CdS) to 2.36 eV ( i.e., bulk CdS). By adding the CdCl2 precursor at a specific stage of the bacterial growth cycle, we were able to induce extracellular CdS NP precipitation. Additionally, we adapted extracellular precipitation strategies to form CdS NPs on surfaces as bacterial/PC membrane composites and characterized them by spectroscopic and imaging methods, including energy dispersive spectroscopy, and scanning and transmission electron microscopy. This method allowed us to control the localization of NP precipitation throughout the layered bacterial/membrane composite, by varying the timing of the cadmium precursor addition. Additionally, we demonstrated the photodegradation of methyl orange using the CdS functionalized porous membranes, thus confirming the photocatalytic properties of our composites for eventual translation to device development. We finally also explored the precipitation of other metallic NPs using our bacterial system, using enzyme extracted from our bacterial system, and using commercially available, his-tagged enzyme. We hope to extend this research to tethering enzymes on surfaces to direct NP precipitation. Taken all together, our results show the great promise bacteria have for the fabrication of tunable, transition metal NPs with useful electronic properties.

Interactions of Native Cyclodextrins with Metal Ions and Inorganic Nanoparticles: Fertile Landscape for Chemistry and Materials Science.

PubMed

Prochowicz, Daniel; Kornowicz, Arkadiusz; Lewiński, Janusz

2017-11-22

Readily available cyclodextrins (CDs) with an inherent hydrophobic internal cavity and hydrophilic external surface are macrocyclic entities that display a combination of molecular recognition and complexation properties with vital implications for host-guest supramolecular chemistry. While the host-guest chemistry of CDs has been widely recognized and led to their exploitation in a variety of important functions over the last five decades, these naturally occurring macrocyclic systems have emerged only recently as promising macrocyclic molecules to fabricate environmentally benign functional nanomaterials. This review surveys the development in the field paying special attention to the synthesis and emerging uses of various unmodified CD-metal complexes and CD-inorganic nanoparticle systems and identifies possible future directions. The association of a hydrophobic cavity of CDs with metal ions or various inorganic nanoparticles is a very appealing strategy for controlling the inorganic subunits properties in the very competitive water environment. In this review we provide the most prominent examples of unmodified CDs' inclusion complexes with organometallic guests and update the research in this field from the past decade. We discuss also the coordination flexibility of native CDs to metal ions in CD-based metal complexes and summarize the progress in the synthesis and characterization of CD-metal complexes and their use in catalysis and sensing as well as construction of molecular magnets. Then we provide a comprehensive overview of emerging applications of native CDs in materials science and nanotechnology. Remarkably, in the past few years CDs have appeared as attractive building units for the synthesis of carbohydrate metal-organic frameworks (CD-MOFs) in a combination of alkali-metal cations. The preparation of this new class of highly porous materials and their applications in the separation of small molecules, the loading of drug molecules, as well as efficient host templates in the construction of nanomaterials with the desired functionality, including the first-in-class devices including sensors and memristors, are highlighted. Finally, CDs as well-known "green" molecular hosts have also been used as ideal functional molecules to improve the solubility, stability, and bioavailability of inorganic nanoparticles. In this regard, we demonstrate various strategies for the preparation of native CDs-modified inorganic nanomaterials such as metal, metal oxide, and semiconductor and magnetic nanoparticles, aiming to take advantage of both the controlled properties of the inorganic core and the controlled properties of the coating molecules. The functionalization of a CD hydrophobic cavity with an inorganic nanoparticle is very prospective for the development of novel catalytic systems and new tools for highly selective and sensitive sensing platforms for various targets.

Ag plasmonic nanostructures and a novel gel electrolyte in a high efficiency TiO2/CdS solar cell.

PubMed

Kumar, P Naresh; Deepa, Melepurath; Srivastava, Avanish Kumar

2015-04-21

A novel photoanode architecture with plasmonic silver (Ag) nanostructures embedded in titania (TiO2), which served as the wide band gap semiconducting support and CdS quantum dots (QDs), as light absorbers, is presented. Ag nanostructures were prepared by a polyol method and are comprised of clumps of nanorods, 15-35 nm wide, interspersed with globular nanoparticles and they were characterized by a face centered cubic lattice. Optimization of Ag nanostructures was achieved on the basis of a superior power conversion efficiency (PCE) obtained for the cell with a Ag/TiO2/CdS electrode encompassing a mixed morphology of Ag nano-rods and particles, relative to analogous cells with either Ag nanoparticles or Ag nanorods. Interfacial charge transfer kinetics was unraveled by fluorescence quenching and lifetime studies. Ag nanostructures improve the light harvesting ability of the TiO2/CdS photoanode via (a) plasmonic and scattering effects, which induce both near- and far-field enhancements which translate to higher photocurrent densities and (b) charging effects, whereby, photoexcited electron transfer from TiO2 to Ag is facilitated by Fermi level equilibration. Owing to the spectacular ability of Ag nanostructures to increase light absorption, a greatly increased PCE of 4.27% and a maximum external quantum efficiency of 55% (at 440 nm) was achieved for the cell based on Ag/TiO2/CdS, greater by 42 and 66%, respectively, compared to the TiO2/CdS based cell. In addition, the liquid S(2-) electrolyte was replaced by a S(2-) gel containing fumed silica, and the redox potential, conductivity and p-type conduction of the two were deduced to be comparable. Although the gel based cells showed diminished solar cell performances compared to their liquid counterparts, nonetheless, the Ag/TiO2/CdS electrode continued to outperform the TiO2/CdS electrode. Our studies demonstrate that Ag nanostructures effectively capture a significant chunk of the electromagnetic spectrum and aid QD solar cells in delivering high power conversion efficiencies.

ADESSA: A Real-Time Decision Support Service for Delivery of Semantically Coded Adverse Drug Event Data

PubMed Central

Duke, Jon D.; Friedlin, Jeff

2010-01-01

Evaluating medications for potential adverse events is a time-consuming process, typically involving manual lookup of information by physicians. This process can be expedited by CDS systems that support dynamic retrieval and filtering of adverse drug events (ADE’s), but such systems require a source of semantically-coded ADE data. We created a two-component system that addresses this need. First we created a natural language processing application which extracts adverse events from Structured Product Labels and generates a standardized ADE knowledge base. We then built a decision support service that consumes a Continuity of Care Document and returns a list of patient-specific ADE’s. Our database currently contains 534,125 ADE’s from 5602 product labels. An NLP evaluation of 9529 ADE’s showed recall of 93% and precision of 95%. On a trial set of 30 CCD’s, the system provided adverse event data for 88% of drugs and returned these results in an average of 620ms. PMID:21346964

Vapor Compression and Thermoelectric Heat Pumps for a Cascade Distillation Subsystem: Design and Experiment

NASA Technical Reports Server (NTRS)

Erickson, Lisa R.; Ungar, Eugene K.

2012-01-01

Humans on a spacecraft require significant amounts of water for drinking, food, hydration, and hygiene. Maximizing the reuse of wastewater while minimizing the use of consumables is critical for long duration space exploration. One of the more promising consumable-free methods of reclaiming wastewater is the distillation/condensation process used in the Cascade Distillation Subsystem (CDS). The CDS heats wastewater to the point of vaporization then condenses and cools the resulting water vapor. The CDS wastewater flow requires heating for evaporation and the product water flow requires cooling for condensation. Performing the heating and cooling processes separately would require two separate units, each of which would demand large amounts of electrical power. Mass, volume, and power efficiencies can be obtained by heating the wastewater and cooling the condensate in a single heat pump unit. The present work describes and compares two competing heat pump methodologies that meet the needs of the CDS: 1) a series of mini compressor vapor compression cycles and 2) a thermoelectric heat exchanger. In the paper, the CDS system level requirements are outlined, the designs of the two heat pumps are described in detail, and the results of heat pump analysis and performance tests are provided. The mass, volume, and power requirement for each heat pump option is compared and the advantages and disadvantages of each system are listed.

Assessment of the management factors that influence the development of preventive care in the New South Wales public dental service.

PubMed

Masoe, Angela V; Blinkhorn, Anthony S; Taylor, Jane; Blinkhorn, Fiona A

2015-01-01

Oral diseases, particularly dental caries, remain one of the most common chronic health problems for adolescents, and are a major public health concern. Public dental services in New South Wales, Australia offer free clinical care and preventive advice to all adolescents under 18 years of age, particularly those from disadvantaged backgrounds. This care is provided by dental therapists and oral health therapists (therapists). It is incumbent upon clinical directors (CDs) and health service managers (HSMs) to ensure that the appropriate clinical preventive care is offered by clinicians to all their patients. The aims of this study were to 1) explore CDs' and HSMs' perceptions of the factors that could support the delivery of preventive care to adolescents, and to 2) record the strategies they have utilized to help therapists provide preventive care to adolescents. In-depth, semistructured interviews were undertaken with 19 CDs and HSMs from across NSW local health districts. A framework matrix was used to systematically code data and enable key themes to be identified for analysis. The 19 CDs and HSMs reported that fiscal accountability and meeting performance targets impacted on the levels and types of preventive care provided by therapists. Participants suggested that professional clinical structures for continuous quality improvement should be implemented and monitored, and that an adequate workforce mix and more resources for preventive dental care activities would enhance therapists' ability to provide appropriate levels of preventive care. CDs and HSMs stated that capitalizing on the strengths of visiting pediatric dental specialists and working with local health district clinical leaders would be a practical way to improve models of preventive oral health care for adolescents. The main issue raised in this study is that preventive dentistry per se lacks strong support from the central funding agency, and that increasing prevention activities is not a simple task of changing regulations or increasing professional education.

Multifunctional core-shell silica microspheres and their performance in self-carrier decomposition, sustained drug release and fluorescent bioimaging

NASA Astrophysics Data System (ADS)

Mehdi, Yamina Ait; Itatahine, Asma; Fizir, Meriem; Xiao, Deli; Dramou, Pierre; He, Hua

2018-07-01

An ideal nanocarrier system for drug delivery is that one made from biocompatible and biodegradable materials for safe excretion from the biological system, and often with additional imaging abilities. In the present work, new core-shell silica microspheres have been prepared, with carrier decomposition after drug release. Paclitaxel, which is one of the most efficient drugs against a wide range of malignancies was integrated into the silica core. The carrier decomposition resulted from the escape of drug molecules with loading capacity about 16.95%. To achieve the fluorescents properties of the synthesized material a biocompatible photoluminescent prepared carbon dots were inserted in a silica shell around the Ptx-SiO2 core. The resultant silica core-shell (Ptx-SiO2CDs-SiO2) NPs with average particle size around 100 nm showed high fluorescent properties from the confocal laser scanning microscope observation. Further observation under UV-light at 365 nm also confirmed the photoluminescence. The Ptx-SiO2@CDs-SiO2 NPs were highly water soluble, and provide a sustained drug release as well as pH sensitivity. The incubation of A549 cells line with Ptx-SiO2@CDs-SiO2 NPs exhibits high cellular uptake as shown by CDs imaging. These properties in addition to the biocompatibility of Ptx-SiO2@CDs-SiO2 NPs and biodegradability of the silica core contributed simultaneously with the drug release process for easy body excretion after its functionality via renal system.

High-end clinical domain information systems for effective healthcare delivery.

PubMed

Mangalampalli, Ashish; Rama, Chakravarthy; Muthiyalian, Raja; Jain, Ajeet K

2007-01-01

The Electronic Health Record (EHR) provides doctors with a quick, reliable, secure, real-time and user-friendly source of all relevant patient data. The latest information system technologies, such as Clinical Data Warehouses (CDW), Clinical Decision-Support (CDS) systems and data-mining techniques (Online Analytical Processing (OLAP) and Online Transactional Processing (OLTP)), are used to maintain and utilise patient data intelligently, based on the users' requirements. Moreover, clinical trial reports for new drug approvals are now being submitted electronically for faster and easier processing. Also, information systems are used in educating patients about the latest developments in medical science through the internet and specially configured kiosks in hospitals and clinics.

Direct Z-scheme TiO2/CdS hierarchical photocatalyst for enhanced photocatalytic H2-production activity

NASA Astrophysics Data System (ADS)

Meng, Aiyun; Zhu, Bicheng; Zhong, Bo; Zhang, Liuyang; Cheng, Bei

2017-11-01

Photocatalytic H2 evolution, which utilizes solar energy via water splitting, is a promising route to deal with concerns about energy and environment. Herein, a direct Z-scheme TiO2/CdS binary hierarchical photocatalyst was fabricated via a successive ionic layer adsorption and reaction (SILAR) technique, and photocatalytic H2 production was measured afterwards. The as-prepared TiO2/CdS hybrid photocatalyst exhibited noticeably promoted photocatalytic H2-production activity of 51.4 μmol h-1. The enhancement of photocatalytic activity was ascribed to the hierarchical structure, as well as the efficient charge separation and migration from TiO2 nanosheets to CdS nanoparticles (NPs) at their tight contact interfaces. Moreover, the direct Z-scheme photocatalytic reaction mechanism was demonstrated to elucidate the improved photocatalytic performance of TiO2/CdS composite photocatalyst. The photoluminescence (PL) analysis of hydroxyl radicals were conducted to provide clues for the direct Z-scheme mechanism. This work provides a facile route for the construction of redox mediator-free Z-scheme photocatalytic system for photocatalytic water splitting.

The iron stimulon of Xylella fastidiosa includes genes for type IV pilus and colicin V-like bacteriocins.

PubMed

Zaini, Paulo A; Fogaça, Andréa C; Lupo, Fernanda G N; Nakaya, Helder I; Vêncio, Ricardo Z N; da Silva, Aline M

2008-04-01

Xylella fastidiosa is the etiologic agent of a wide range of plant diseases, including citrus variegated chlorosis (CVC), a major threat to citrus industry. The genomes of several strains of this phytopathogen were completely sequenced, enabling large-scale functional studies. DNA microarrays representing 2,608 (91.6%) coding sequences (CDS) of X. fastidiosa CVC strain 9a5c were used to investigate transcript levels during growth with different iron availabilities. When treated with the iron chelator 2,2'-dipyridyl, 193 CDS were considered up-regulated and 216 were considered down-regulated. Upon incubation with 100 microM ferric pyrophosphate, 218 and 256 CDS were considered up- and down-regulated, respectively. Differential expression for a subset of 44 CDS was further evaluated by reverse transcription-quantitative PCR. Several CDS involved with regulatory functions, pathogenicity, and cell structure were modulated under both conditions assayed, suggesting that major changes in cell architecture and metabolism occur when X. fastidiosa cells are exposed to extreme variations in iron concentration. Interestingly, the modulated CDS include those related to colicin V-like bacteriocin synthesis and secretion and to functions of pili/fimbriae. We also investigated the contribution of the ferric uptake regulator Fur to the iron stimulon of X. fastidiosa. The promoter regions of the strain 9a5c genome were screened for putative Fur boxes, and candidates were analyzed by electrophoretic mobility shift assays. Taken together, our data support the hypothesis that Fur is not solely responsible for the modulation of the iron stimulon of X. fastidiosa, and they present novel evidence for iron regulation of pathogenicity determinants.

Workshop on using natural language processing applications for enhancing clinical decision making: an executive summary

PubMed Central

Pai, Vinay M; Rodgers, Mary; Conroy, Richard; Luo, James; Zhou, Ruixia; Seto, Belinda

2014-01-01

In April 2012, the National Institutes of Health organized a two-day workshop entitled ‘Natural Language Processing: State of the Art, Future Directions and Applications for Enhancing Clinical Decision-Making’ (NLP-CDS). This report is a summary of the discussions during the second day of the workshop. Collectively, the workshop presenters and participants emphasized the need for unstructured clinical notes to be included in the decision making workflow and the need for individualized longitudinal data tracking. The workshop also discussed the need to: (1) combine evidence-based literature and patient records with machine-learning and prediction models; (2) provide trusted and reproducible clinical advice; (3) prioritize evidence and test results; and (4) engage healthcare professionals, caregivers, and patients. The overall consensus of the NLP-CDS workshop was that there are promising opportunities for NLP and CDS to deliver cognitive support for healthcare professionals, caregivers, and patients. PMID:23921193

Agmatine: a novel endogenous vasodilator substance.

PubMed

Gao, Y; Gumusel, B; Koves, G; Prasad, A; Hao, Q; Hyman, A; Lippton, H

1995-01-01

The purpose of the study was to investigate the effects of agmatine, an endogenous clonidine-displacing substance (CDS), on systemic hemodynamics in the anesthetized rat. Bolus intravenous (i.v.) injections of agmatine decreased systemic arterial pressure (SAP) and systemic vascular resistance in a dose-dependent manner. The development of acute tachyphylaxis to the systemic vasodepressor response to agmatine did not induce cross-tachyphylaxis to the systemic vasodepressor responses to bradykinin, isoproterenol and nitroglycerin. The present data demonstrate agmatine, as a CDS and agonist for imidazoline (I) receptors, possesses marked systemic vasodilator activity in the rat. The present data suggest that activation of I receptors may represent a novel mechanism of vasodilation in vivo.

75 FR 17181 - Order Extending Temporary Exemptions Under the Securities Exchange Act of 1934 in Connection With...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-05

... CDS market, and thus can help mitigate potential systemic impact. We have therefore found that taking action to help foster the prompt development of CCPs, including granting temporary conditional exemptions... number of benefits by helping to promote efficiency and reduce risk in the CDS market, by contributing to...

A bilaminated decellularized scaffold for islet transplantation: Structure, properties and functions in diabetic mice.

PubMed

Wang, Xi; Wang, Kai; Zhang, Wei; Qiang, Ming; Luo, Ying

2017-09-01

Ectopic transplantation of islets provides a beta cell-replacement approach that may allow the recovery of physiological regulation of the blood sugar level in patients with Type I diabetes (T1D). In development of new extrahepatic islet transplantation protocols in support of the islet engraftment, it is pivotal to develop scaffold materials with multifaceted functions to provide beneficial microenvironment, mediate host response in favor of vascularization/islet integration and maintain long-term islet function at the transplantation site. In this study, a new composite bilaminar decellularized scaffold (CDS) was fabricated with differential structural, degradation and mechanical properties by the combination of a fast-degrading porous collagen matrix and a mechanically supportive porcine pericardium. When investigated in the epididymal fat pad in syngeneic mouse models, it was shown that CDS could serve as superior scaffolds to promote islet adhesion and viability, and islet-CDS constructs also allowed rapid reversal of the hyperglycemic condition in the host. The engraftment and effects of islets were achieved at low islet numbers, accompanied by minimal adverse tissue reactions and optimal islet integration with the surrounding fat tissue. The bioactive surface, mechanical/chemical durability and biocompatibility of the CDS may all have played important roles in facilitating the engraftment of islets. Our study provided new insights into scaffold's function in the interplay of cells, materials and host tissue and the extracellular matrix-based scaffolds have potential for clinical translation in the beta cell-replacement therapy to treat T1D. Copyright © 2017 Elsevier Ltd. All rights reserved.

Highly efficient visible-light-driven photocatalytic hydrogen production of CdS-cluster-decorated graphene nanosheets.

PubMed

Li, Qin; Guo, Beidou; Yu, Jiaguo; Ran, Jingrun; Zhang, Baohong; Yan, Huijuan; Gong, Jian Ru

2011-07-20

The production of clean and renewable hydrogen through water splitting using photocatalysts has received much attention due to the increasing global energy crises. In this study, a high efficiency of the photocatalytic H(2) production was achieved using graphene nanosheets decorated with CdS clusters as visible-light-driven photocatalysts. The materials were prepared by a solvothermal method in which graphene oxide (GO) served as the support and cadmium acetate (Cd(Ac)(2)) as the CdS precursor. These nanosized composites reach a high H(2)-production rate of 1.12 mmol h(-1) (about 4.87 times higher than that of pure CdS nanoparticles) at graphene content of 1.0 wt % and Pt 0.5 wt % under visible-light irradiation and an apparent quantum efficiency (QE) of 22.5% at wavelength of 420 nm. This high photocatalytic H(2)-production activity is attributed predominantly to the presence of graphene, which serves as an electron collector and transporter to efficiently lengthen the lifetime of the photogenerated charge carriers from CdS nanoparticles. This work highlights the potential application of graphene-based materials in the field of energy conversion.

Extending Climate Analytics-As to the Earth System Grid Federation

NASA Astrophysics Data System (ADS)

Tamkin, G.; Schnase, J. L.; Duffy, D.; McInerney, M.; Nadeau, D.; Li, J.; Strong, S.; Thompson, J. H.

2015-12-01

We are building three extensions to prior-funded work on climate analytics-as-a-service that will benefit the Earth System Grid Federation (ESGF) as it addresses the Big Data challenges of future climate research: (1) We are creating a cloud-based, high-performance Virtual Real-Time Analytics Testbed supporting a select set of climate variables from six major reanalysis data sets. This near real-time capability will enable advanced technologies like the Cloudera Impala-based Structured Query Language (SQL) query capabilities and Hadoop-based MapReduce analytics over native NetCDF files while providing a platform for community experimentation with emerging analytic technologies. (2) We are building a full-featured Reanalysis Ensemble Service comprising monthly means data from six reanalysis data sets. The service will provide a basic set of commonly used operations over the reanalysis collections. The operations will be made accessible through NASA's climate data analytics Web services and our client-side Climate Data Services (CDS) API. (3) We are establishing an Open Geospatial Consortium (OGC) WPS-compliant Web service interface to our climate data analytics service that will enable greater interoperability with next-generation ESGF capabilities. The CDS API will be extended to accommodate the new WPS Web service endpoints as well as ESGF's Web service endpoints. These activities address some of the most important technical challenges for server-side analytics and support the research community's requirements for improved interoperability and improved access to reanalysis data.

Pharmacogenomic knowledge representation, reasoning and genome-based clinical decision support based on OWL 2 DL ontologies.

PubMed

Samwald, Matthias; Miñarro Giménez, Jose Antonio; Boyce, Richard D; Freimuth, Robert R; Adlassnig, Klaus-Peter; Dumontier, Michel

2015-02-22

Every year, hundreds of thousands of patients experience treatment failure or adverse drug reactions (ADRs), many of which could be prevented by pharmacogenomic testing. However, the primary knowledge needed for clinical pharmacogenomics is currently dispersed over disparate data structures and captured in unstructured or semi-structured formalizations. This is a source of potential ambiguity and complexity, making it difficult to create reliable information technology systems for enabling clinical pharmacogenomics. We developed Web Ontology Language (OWL) ontologies and automated reasoning methodologies to meet the following goals: 1) provide a simple and concise formalism for representing pharmacogenomic knowledge, 2) finde errors and insufficient definitions in pharmacogenomic knowledge bases, 3) automatically assign alleles and phenotypes to patients, 4) match patients to clinically appropriate pharmacogenomic guidelines and clinical decision support messages and 5) facilitate the detection of inconsistencies and overlaps between pharmacogenomic treatment guidelines from different sources. We evaluated different reasoning systems and test our approach with a large collection of publicly available genetic profiles. Our methodology proved to be a novel and useful choice for representing, analyzing and using pharmacogenomic data. The Genomic Clinical Decision Support (Genomic CDS) ontology represents 336 SNPs with 707 variants; 665 haplotypes related to 43 genes; 22 rules related to drug-response phenotypes; and 308 clinical decision support rules. OWL reasoning identified CDS rules with overlapping target populations but differing treatment recommendations. Only a modest number of clinical decision support rules were triggered for a collection of 943 public genetic profiles. We found significant performance differences across available OWL reasoners. The ontology-based framework we developed can be used to represent, organize and reason over the growing wealth of pharmacogenomic knowledge, as well as to identify errors, inconsistencies and insufficient definitions in source data sets or individual patient data. Our study highlights both advantages and potential practical issues with such an ontology-based approach.

Structural, Optical, and Electrical Properties of Cobalt-Doped CdS Quantum Dots

NASA Astrophysics Data System (ADS)

Thambidurai, M.; Muthukumarasamy, N.; Velauthapillai, Dhayalan; Agilan, S.; Balasundaraprabhu, R.

2012-04-01

In the present work, a systematic study has been carried out to understand the influence of cobalt (Co) doping on various properties of CdS nanoparticles. CdS and Co-doped CdS quantum dots have been prepared at room temperature using a chemical precipitation method without using catalysts, capping agents, or surfactants. X-ray diffraction reveals that both undoped and Co-doped CdS nanoparticles exhibit hexagonal structure without any impurity phase, and the lattice constants of CdS nanoparticles are observed to decrease slightly with increasing cobalt concentration. High-resolution transmission electron microscopy (HRTEM) shows that the particle size of CdS and 5.02% Co-doped CdS nanoparticles is in the range of 2 nm to 4 nm. The Raman spectra of Co-doped CdS nanoparticles exhibit a red-shift compared with that of bulk CdS, which may be attributed to optical phonon confinement. The optical absorption spectra of Co-doped CdS nanoparticles also exhibit a red-shift with respect to that of CdS nanoparticles. The electrical conductivity of CdS and Co-doped CdS nanoparticles is found to increase with increasing temperature and cobalt concentration.

Confinement of carbon dots localizing to the ultrathin layered double hydroxides toward simultaneous triple-mode bioimaging and photothermal therapy.

PubMed

Weng, Yangziwan; Guan, Shanyue; Lu, Heng; Meng, Xiangmin; Kaassis, Abdessamad Y; Ren, Xiaoxue; Qu, Xiaozhong; Sun, Chenghua; Xie, Zheng; Zhou, Shuyun

2018-07-01

It is a great challenge to develop multifunctional nanocarriers for cancer diagnosis and therapy. Herein, versatile CDs/ICG-uLDHs nanovehicles for triple-modal fluorescence/photoacoustic/two-photon bioimaging and effective photothermal therapy were prepared via a facile self-assembly of red emission carbon dots (CDs), indocyanine green (ICG) with the ultrathin layered double hydroxides (uLDHs). Due to the J-aggregates of ICG constructed in the self-assembly process, CDs/ICG-uLDHs was able to stabilize the photothermal agent ICG and enhanced its photothermal efficiency. Furthermore, the unique confinement effect of uLDHs has extended the fluorescence lifetime of CDs in favor of bioimaging. Considering the excellent in vitro and in vivo phototherapeutics and multimodal imaging effects, this work provides a promising platform for the construction of multifunctional theranostic nanocarrier system for the cancer treatment. Copyright © 2018 Elsevier B.V. All rights reserved.

Encapsulation of biocides by cyclodextrins: toward synergistic effects against pathogens

PubMed Central

Nardello-Rataj, Véronique

2014-01-01

Summary Host–guest chemistry is useful for the construction of nanosized objects. Some of the widely used hosts are probably the cyclodextrins (CDs). CDs can form water-soluble complexes with numerous hydrophobic compounds. They have been widespread used in medicine, drug delivery and are of interest for the biocides encapsulation. Indeed, this enables the development of more or less complex systems that release antimicrobial agents with time. In this paper, the general features of CDs and their applications in the field of biocides have been reviewed. As the key point is the formation of biocide–CD inclusion complexes, this review deals with this in depth and the advantages of biocide encapsulation are highlighted throughout several examples from the literature. Finally, some future directions of investigation have been proposed. We hope that scientists studying biocide applications receive inspiration from this review to exploit the opportunities offered by CDs in their respective research areas. PMID:25550722

Study of poly(N,N-dimethylacrylamide)/CdS nanocomposite organic/inorganic gels.

PubMed

Bekiari, Vlasoula; Pagonis, Konstantinos; Bokias, Georgios; Lianos, Panagiotis

2004-09-14

CdS nanoparticles have been synthesized and stabilized in poly(N,N-dimethylacrylamide) hydrogels. The properties of the composite material have been characterized by UV-vis spectroscopy, scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, and steady-state and time-resolved luminescence spectroscopy. This material can be obtained in three different states: swollen, shrunk, and freeze-dried. The swollen and the freeze-dried states correspond to a nanocomposite organic/inorganic (wet or dry) gel containing CdS nanoparticles of approximately 50 nm diameter while the shrunk state is a two-phase system containing CdS crystals, which precipitate forming interesting geometrical shapes.

Promotion effect of nickel loaded on CdS for photocatalytic H2 production in lactic acid solution

NASA Astrophysics Data System (ADS)

Chen, Shu; Chen, Xiaoping; Jiang, Qizhong; Yuan, Jian; Lin, Caifang; Shangguan, Wenfeng

2014-10-01

Low-cost Ni modified CdS was prepared via a hydrothermal reduction method. The hydrogen production activity of CdS loaded with 5 wt% Ni under visible light was even higher than that of the one loaded with 0.5 wt% Pt. The highest H2 evolution rate (3004.8 μmol h-1) occurred when the concentration of sacrificial agent (lactic acid) was 50 vol%. The nickel can quickly transfer excited electrons and enhance the photocatalytic H2 production activity. It was also found that the hydrogen evolution in this system was generated steadily from both water and lactic acid.

Physician Attitudes toward Adopting Genome-Guided Prescribing through Clinical Decision Support

PubMed Central

Overby, Casey Lynnette; Erwin, Angelika Ludtke; Abul-Husn, Noura S.; Ellis, Stephen B.; Scott, Stuart A.; Obeng, Aniwaa Owusu; Kannry, Joseph L.; Hripcsak, George; Bottinger, Erwin P.; Gottesman, Omri

2014-01-01

This study assessed physician attitudes toward adopting genome-guided prescribing through clinical decision support (CDS), prior to enlisting in the Clinical Implementation of Personalized Medicine through Electronic Health Records and Genomics pilot pharmacogenomics project (CLIPMERGE PGx). We developed a survey instrument that includes the Evidence Based Practice Attitude Scale, adapted to measure attitudes toward adopting genome-informed interventions (EBPAS-GII). The survey also includes items to measure physicians’ characteristics (awareness, experience, and perceived usefulness), attitudes about personal genome testing (PGT) services, and comfort using technology. We surveyed 101 General Internal Medicine physicians from the Icahn School of Medicine at Mount Sinai (ISMMS). The majority were residency program trainees (~88%). Prior to enlisting into CLIPMERGE PGx, most physicians were aware of and had used decision support aids. Few physicians, however, were aware of and had used genome-guided prescribing. The majority of physicians viewed decision support aids and genotype data as being useful for making prescribing decisions. Most physicians had not heard of, but were willing to use, PGT services and felt comfortable interpreting PGT results. Most physicians were comfortable with technology. Physicians who perceived genotype data to be useful in making prescribing decisions, had more positive attitudes toward adopting genome-guided prescribing through CDS. Our findings suggest that internal medicine physicians have a deficit in their familiarity and comfort interpreting and using genomic information. This has reinforced the importance of gathering feedback and guidance from our enrolled physicians when designing genome-guided CDS and the importance of prioritizing genomic medicine education at our institutions. PMID:25562141

Photovoltaic cell with thin CS layer

DOEpatents

Jordan, John F.; Albright, Scot P.

1994-01-18

An improved photovoltaic panel and method of forming a photovoltaic panel are disclosed for producing a high efficiency CdS/CdTe photovoltaic cell. The photovoltaic panel of the present invention is initially formed with a substantially thick Cds layer, and the effective thickness of the CdS layer is substantially reduced during regrowth to both form larger diameter CdTe crystals and substantially reduce the effective thickness of the C This invention was made with Government support under Subcontract No. ZL-7-06031-3 awarded by the Department of Energy. The Government has certain rights in this invention.

Adsorption, Aggregation, and Deposition Behaviors of Carbon Dots on Minerals.

PubMed

Liu, Xia; Li, Jiaxing; Huang, Yongshun; Wang, Xiangxue; Zhang, Xiaodong; Wang, Xiangke

2017-06-06

The increased production of carbon dots (CDs) and the release and accumulation of CDs in both surface and groundwater has resulted in the increasing interest in their research. To assess the environmental behavior of CDs, the interaction between CDs and goethite was studied under different environmental conditions. Electrokinetic characterization of CDs suggested that the ζ-potential and size distribution of CDs were affected by pH and electrolyte species, indicating that these factors influenced the stability of CDs in aqueous solutions. Traditional Derjaguin-Landau-Verwey-Overbeek theory did not fit well the aggregation process of CDs. Results of the effects of pH and ionic strength suggested that electronic attraction dominated the aggregation of CDs. Compared with other minerals, hydrogen-bonding interactions and Lewis acid-base interactions contributed to the aggregation of CDs, in addition to van der Waals and electrical double-layer forces. Adsorption isotherms and microscopic Fourier transformed infrared spectroscopy indicated that chemical bonds were formed between CDs and goethite. These findings are useful to understand the interaction of CDs with minerals, as well as the potential fate and toxicity of CDs in the natural environment, especially in soils and sediments.

Study of electrostatically self-assembled thin films of CdS and ZnS nanoparticle semiconductors

NASA Astrophysics Data System (ADS)

Suryajaya

In this work, CdS and ZnS semiconducting colloid nanoparticles coated with organic shell, containing either SO[3-] or NH[2+] groups, were deposited as thin films using the technique of electrostatic self-assembly. The films produced were characterized with UV-vis spectroscopy and spectroscopic ellipsometry - for optical properties; atomic force microscopy (AFM) - for morphology study; mercury probe - for electrical characterisation; and photon counter - for electroluminescence study. UV-vis spectra show a substantial blue shift of the main absorption band of both CdS and ZnS, either in the form of solutions or films, with respect to the bulk materials. The calculation of nanoparticles' radii yields the value of about 1.8 nm for both CdS and ZnS.The fitting of standard ellipsometry data gave the thicknesses (d) of nanoparticle layers of around 5 nm for both CdS and ZnS which corresponds well to the size of particles evaluated from UV-vis spectral data if an additional thickness of the organic shell is taken into account. The values of refractive index (n) and extinction coefficient (k) obtained were about 2.28 and 0.7 at 633 nm wavelength, for both CdS and ZnS.Using total internal reflection (TIRE), the process of alternative deposition of poly-allylamine hydrochloride (PAH) and CdS (or ZnS) layers could be monitored in-situ. The dynamic scan shows that the adsorption kinetic of the first layer of PAH or nanoparticles was slower than that of the next layer. The fitting of TIRE spectra gavethicknesses of about 7 nm and 12 nm for CdS and ZnS, respectively. It supports the suggestion of the formation of three-dimensional aggregates of semiconductor nanoparticles intercalated with polyelectrolyte.AFM images show the formation of large aggregates of nanoparticles, about 40-50 nm, for the films deposited from original colloid solutions, while smaller aggregates, about 12-20 nm, were obtained if the colloid solutions were diluted.Current-voltage (I-V) and capacitance-frequency (C-f) measurements of polyelectrolyte/nanoparticles (CdS or ZnS) films suggest the tunnelling behaviour in the films while capacitance- voltage (C-V) and conductance-voltage (G-V) measurements suggest that these nanoparticles are conductive. The electroluminescence was detected in sandwich structures of (PAH/CdS/PAH)[N] using a photon counting detector, but not in the case of ZnS films.

Service Oriented Architecture for Clinical Decision Support: A Systematic Review and Future Directions

PubMed Central

Loya, Salvador Rodriguez; Kawamoto, Kensaku; Chatwin, Chris; Huser, Vojtech

2017-01-01

The use of a service-oriented architecture (SOA) has been identified as a promising approach for improving health care by facilitating reliable clinical decision support (CDS). A review of the literature through October 2013 identified 44 articles on this topic. The review suggests that SOA related technologies such as Business Process Model and Notation (BPMN) and Service Component Architecture (SCA) have not been generally adopted to impact health IT systems’ performance for better care solutions. Additionally, technologies such as Enterprise Service Bus (ESB) and architectural approaches like Service Choreography have not been generally exploited among researchers and developers. Based on the experience of other industries and our observation of the evolution of SOA, we found that the greater use of these approaches have the potential to significantly impact SOA implementations for CDS PMID:25325996

Recommendations for Selecting Drug-Drug Interactions for Clinical Decision Support

PubMed Central

Tilson, Hugh; Hines, Lisa E.; McEvoy, Gerald; Weinstein, David M.; Hansten, Philip D.; Matuszewski, Karl; le Comte, Marianne; Higby-Baker, Stefanie; Hanlon, Joseph T.; Pezzullo, Lynn; Vieson, Kathleen; Helwig, Amy L.; Huang, Shiew-Mei; Perre, Anthony; Bates, David W.; Poikonen, John; Wittie, Michael A.; Grizzle, Amy J.; Brown, Mary; Malone, Daniel C.

2016-01-01

Purpose To recommend principles for including drug-drug interactions (DDIs) in clinical decision support. Methods A conference series was conducted to improve clinical decision support (CDS) for DDIs. The Content Workgroup met monthly by webinar from January 2013 to February 2014, with two in-person meetings to reach consensus. The workgroup consisted of 20 experts in pharmacology, drug information, and CDS from academia, government agencies, health information (IT) vendors, and healthcare organizations. Workgroup members addressed four key questions: (1) What process should be used to develop and maintain a standard set of DDIs?; (2) What information should be included in a knowledgebase of standard DDIs?; (3) Can/should a list of contraindicated drug pairs be established?; and (4) How can DDI alerts be more intelligently filtered? Results To develop and maintain a standard set of DDIs for CDS in the United States, we recommend a transparent, systematic, and evidence-driven process with graded recommendations by a consensus panel of experts and oversight by a national organization. We outline key DDI information needed to help guide clinician decision-making. We recommend judicious classification of DDIs as contraindicated, as only a small set of drug combinations are truly contraindicated. Finally, we recommend more research to identify methods to safely reduce repetitive and less relevant alerts. Conclusion A systematic ongoing process is necessary to select DDIs for alerting clinicians. We anticipate that our recommendations can lead to consistent and clinically relevant content for interruptive DDIs, and thus reduce alert fatigue and improve patient safety. PMID:27045070

Anopheles gambiae genome reannotation through synthesis of ab initio and comparative gene prediction algorithms

PubMed Central

Li, Jun; Riehle, Michelle M; Zhang, Yan; Xu, Jiannong; Oduol, Frederick; Gomez, Shawn M; Eiglmeier, Karin; Ueberheide, Beatrix M; Shabanowitz, Jeffrey; Hunt, Donald F; Ribeiro, José MC; Vernick, Kenneth D

2006-01-01

Background Complete genome annotation is a necessary tool as Anopheles gambiae researchers probe the biology of this potent malaria vector. Results We reannotate the A. gambiae genome by synthesizing comparative and ab initio sets of predicted coding sequences (CDSs) into a single set using an exon-gene-union algorithm followed by an open-reading-frame-selection algorithm. The reannotation predicts 20,970 CDSs supported by at least two lines of evidence, and it lowers the proportion of CDSs lacking start and/or stop codons to only approximately 4%. The reannotated CDS set includes a set of 4,681 novel CDSs not represented in the Ensembl annotation but with EST support, and another set of 4,031 Ensembl-supported genes that undergo major structural and, therefore, probably functional changes in the reannotated set. The quality and accuracy of the reannotation was assessed by comparison with end sequences from 20,249 full-length cDNA clones, and evaluation of mass spectrometry peptide hit rates from an A. gambiae shotgun proteomic dataset confirms that the reannotated CDSs offer a high quality protein database for proteomics. We provide a functional proteomics annotation, ReAnoXcel, obtained by analysis of the new CDSs through the AnoXcel pipeline, which allows functional comparisons of the CDS sets within the same bioinformatic platform. CDS data are available for download. Conclusion Comprehensive A. gambiae genome reannotation is achieved through a combination of comparative and ab initio gene prediction algorithms. PMID:16569258

A simple and sensitive flow injection method based on the catalytic activity of CdS quantum dots in an acidic permanganate chemiluminescence system for determination of formaldehyde in water and wastewater.

PubMed

Khataee, Alireza; Lotfi, Roya; Hasanzadeh, Aliyeh; Iranifam, Mortaza

2016-04-01

A simple and sensitive flow injection chemiluminescence (CL) method in which CdS quantum dots (QDs) enhanced the CL intensity of a KMnO4-formaldehyde (HCHO) reaction was offered for the determination of HCHO. This CL system was based on the catalytic activity of CdS QDs and their participation in the CL resonance energy transfer (CRET) phenomenon. A possible mechanism for the supplied CL system was proposed using the kinetic curves of the CL systems and the spectra of CL, photoluminescence (PL) and ultraviolet-visible (UV-Vis). The emanated CL intensity of the KMnO4-CdS QDs system was amplified in the presence of a trace level of HCHO. Based on this enhancement effect, a simple and sensitive flow injection CL method was suggested for the determination of HCHO concentration in environmental water and wastewater samples. Under selected optimized experimental conditions, the increased CL intensity was proportional to the HCHO concentration in the range of 0.03-4.5 μg L(-1) and 4.5-10.0 μg L(-1). The detection limits (3σ) were 0.0003 μg L(-1) and 1.2 μg L(-1). The relative standard deviations (RSD%) for eleven replicate determinations of 4.0 μg L(-1) HCHO were 2.2%. Furthermore, the feasibility of the developed method was investigated via the determination of HCHO concentration in environmental water and wastewater samples.

Physicians’ use of computerized clinical decision supports to improve medication management in the elderly – the Seniors Medication Alert and Review Technology intervention

PubMed Central

Alagiakrishnan, Kannayiram; Wilson, Patricia; Sadowski, Cheryl A; Rolfson, Darryl; Ballermann, Mark; Ausford, Allen; Vermeer, Karla; Mohindra, Kunal; Romney, Jacques; Hayward, Robert S

2016-01-01

Background Elderly people (aged 65 years or more) are at increased risk of polypharmacy (five or more medications), inappropriate medication use, and associated increased health care costs. The use of clinical decision support (CDS) within an electronic medical record (EMR) could improve medication safety. Methods Participatory action research methods were applied to preproduction design and development and postproduction optimization of an EMR-embedded CDS implementation of the Beers’ Criteria for medication management and the Cockcroft–Gault formula for estimating glomerular filtration rates (GFR). The “Seniors Medication Alert and Review Technologies” (SMART) intervention was used in primary care and geriatrics specialty clinics. Passive (chart messages) and active (order-entry alerts) prompts exposed potentially inappropriate medications, decreased GFR, and the possible need for medication adjustments. Physician reactions were assessed using surveys, EMR simulations, focus groups, and semi-structured interviews. EMR audit data were used to identify eligible patient encounters, the frequency of CDS events, how alerts were managed, and when evidence links were followed. Results Analysis of subjective data revealed that most clinicians agreed that CDS appeared at appropriate times during patient care. Although managing alerts incurred a modest time burden, most also agreed that workflow was not disrupted. Prevalent concerns related to clinician accountability and potential liability. Approximately 36% of eligible encounters triggered at least one SMART alert, with GFR alert, and most frequent medication warnings were with hypnotics and anticholinergics. Approximately 25% of alerts were overridden and ~15% elicited an evidence check. Conclusion While most SMART alerts validated clinician choices, they were received as valuable reminders for evidence-informed care and education. Data from this study may aid other attempts to implement Beers’ Criteria in ambulatory care EMRs. PMID:26869776

Drainage water management combined with cover crop enhances reduction of soil phosphorus loss.

PubMed

Zhang, T Q; Tan, C S; Zheng, Z M; Welacky, T; Wang, Y T

2017-05-15

Integrating multiple practices for mitigation of phosphorus (P) loss from soils may enhance the reduction efficiency, but this has not been studied as much as individual ones. A four-year study was conducted to determine the effects of cover crop (CC) (CC vs. no CC, NCC) and drainage water management (DWM) (controlled drainage with sub-irrigation, CDS, vs. regular free tile drainage, RFD) and their interaction on P loss through both surface runoff (SR) and tile drainage (TD) water in a clay loam soil of the Lake Erie region. Cover crop reduced SR flow volume by 32% relative to NCC, regardless of DWM treatment. In contrast, CC increased TD flow volume by 57 and 9.4% with CDS and RFD, respectively, compared to the corresponding DWM treatment with NCC. The total (SR+TD) field water discharge volumes were comparable amongst all the treatments. Cover crop reduced flow-weighted mean (FWM) concentrations of particulate P (PP) by 26% and total P (TP) by 12% in SR, while it didn't affect the FWM dissolved reactive P (DRP) concentration, regardless of DWM treatments. Compared with RFD, CDS reduced FWM DRP concentration in TD water by 19%, while CC reduced FWM PP and TP concentrations in TD by 21 and 17%, respectively. Total (SR+TD) soil TP loss was the least with CDS-CC followed by RFD-CC, CDS-NCC, and RFD-NCC. Compared with RFD-NCC, currently popular practice in the region, total TP loss was reduced by 23% with CDS-CC. The CDS-CC system can be an effective practice to ultimately mitigate soil P loading to water resource. Copyright © 2017 Elsevier B.V. All rights reserved.

On the Role of High Amounts of Mn Element in CdS Structure

NASA Astrophysics Data System (ADS)

Gonullu, Meryem Polat; Kose, Salih

2017-03-01

CdS and MnS are technologically important semiconducting materials. In this work, due to the limited ability of these materials separately, a detailed characterization of the new samples formed by the combined use of them has been reported. CdS films, with the incorporation of Mn in a wide range of concentrations, have been produced by a low-cost Ultrasonic Spray Pyrolysis set-up. Spectroscopic Ellipsometry (SE) has been used to determine the thicknesses and optical constants ( n, k) of the samples. It has been determined that samples with high amounts of Mn have lower refractive index values. Absorbance spectra have shown additional band edges along with the one belonging to CdS, for samples with Mn concentrations higher than 50 pct. This has been attributed to a phase separation above this limit. Raman spectroscopy analysis which shows additional Raman peaks belonging to MnS phase also supports these findings. Depending on this phase separation, crystalline structure has been deteriorated. Surface properties of the samples have been investigated by SEM and AFM. Elemental analysis has been performed by EDS. Resistivity measurements performed by a four-probe set-up have shown that samples containing high amount of Mn have lower electrical resistivity values.

Facile synthesis and luminescence characteristics of high-quality CdS: Eu/ZnS core/shell nanocrystals with biocompatibility.

PubMed

Zhang, Kexin; Zhang, Rui; Yu, Yaxin; Sun, Shuqing

2012-04-01

In this paper, we report a facile method to synthesize high quality CdS: Eu nanocrystals (NCs) and CdS: Eu/ZnS NCs with strong photoluminescence (PL). The influence of various experimental variables including the concentration of Eu3+ ions, the reaction time and the reaction temperature were investigated systematically. In addition, the PL properties of CdS: Eu NCs exhibited pH sensitive. Under the acid condition, pH value of the CdS: Eu NCs solution played an important role in determining PL emission intensity. However, under the alkaline condition, the obtained CdS: Eu NCs exhibited a tunable PL emission wavelength (from 490 nm to 610 nm) when pH value was adjusted from pH 7 to 10. After coating with ZnS shell, the CdS: Eu/ZnS NCs showed enhanced PL intensity compare with one of the CdS: Eu NCs. The CdS: Eu NCs and CdS: Eu/ZnS NCs were characterized by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). In addition, the biocompatibility of these NCs was measured by hemolytic test, which indicated that CdS: Eu/ZnS NCs were more biocompatible than CdS: Eu NCs at the same conditions. It can be expected that CdS: Eu/ZnS NCs are promising biolabeling materials.

Status of neurology medical school education: results of 2005 and 2012 clerkship director survey.

PubMed

Carter, Jonathan L; Ali, Imran I; Isaacson, Richard S; Safdieh, Joseph E; Finney, Glen R; Sowell, Michael K; Sam, Maria C; Anderson, Heather S; Shin, Robert K; Kraakevik, Jeff A; Coleman, Mary; Drogan, Oksana

2014-11-04

To survey all US medical school clerkship directors (CDs) in neurology and to compare results from a similar survey in 2005. A survey was developed by a work group of the American Academy of Neurology Undergraduate Education Subcommittee, and sent to all neurology CDs listed in the American Academy of Neurology database. Comparisons were made to a similar 2005 survey. Survey response rate was 73%. Neurology was required in 93% of responding schools. Duration of clerkships was 4 weeks in 74% and 3 weeks in 11%. Clerkships were taken in the third year in 56%, third or fourth year in 19%, and fourth year in 12%. Clerkship duration in 2012 was slightly shorter than in 2005 (fewer clerkships of ≥4 weeks, p = 0.125), but more clerkships have moved into the third year (fewer neurology clerkships during the fourth year, p = 0.051). Simulation training in lumbar punctures was available at 44% of schools, but only 2% of students attempted lumbar punctures on patients. CDs averaged 20% protected time, but reported that they needed at least 32%. Secretarial full-time equivalent was 0.50 or less in 71% of clerkships. Eighty-five percent of CDs were "very satisfied" or "somewhat satisfied," but more than half experienced "burnout" and 35% had considered relinquishing their role. Trends in neurology undergraduate education since 2005 include shorter clerkships, migration into the third year, and increasing use of technology. CDs are generally satisfied, but report stressors, including inadequate protected time and departmental support. © 2014 American Academy of Neurology.

Status of neurology medical school education

PubMed Central

Ali, Imran I.; Isaacson, Richard S.; Safdieh, Joseph E.; Finney, Glen R.; Sowell, Michael K.; Sam, Maria C.; Anderson, Heather S.; Shin, Robert K.; Kraakevik, Jeff A.; Coleman, Mary; Drogan, Oksana

2014-01-01

Objective: To survey all US medical school clerkship directors (CDs) in neurology and to compare results from a similar survey in 2005. Methods: A survey was developed by a work group of the American Academy of Neurology Undergraduate Education Subcommittee, and sent to all neurology CDs listed in the American Academy of Neurology database. Comparisons were made to a similar 2005 survey. Results: Survey response rate was 73%. Neurology was required in 93% of responding schools. Duration of clerkships was 4 weeks in 74% and 3 weeks in 11%. Clerkships were taken in the third year in 56%, third or fourth year in 19%, and fourth year in 12%. Clerkship duration in 2012 was slightly shorter than in 2005 (fewer clerkships of ≥4 weeks, p = 0.125), but more clerkships have moved into the third year (fewer neurology clerkships during the fourth year, p = 0.051). Simulation training in lumbar punctures was available at 44% of schools, but only 2% of students attempted lumbar punctures on patients. CDs averaged 20% protected time, but reported that they needed at least 32%. Secretarial full-time equivalent was 0.50 or less in 71% of clerkships. Eighty-five percent of CDs were “very satisfied” or “somewhat satisfied,” but more than half experienced “burnout” and 35% had considered relinquishing their role. Conclusion: Trends in neurology undergraduate education since 2005 include shorter clerkships, migration into the third year, and increasing use of technology. CDs are generally satisfied, but report stressors, including inadequate protected time and departmental support. PMID:25305155

Graphitic Nitrogen Triggers Red Fluorescence in Carbon Dots.

PubMed

Holá, Kateřina; Sudolská, Mária; Kalytchuk, Sergii; Nachtigallová, Dana; Rogach, Andrey L; Otyepka, Michal; Zbořil, Radek

2017-12-26

Carbon dots (CDs) are a stable and highly biocompatible fluorescent material offering great application potential in cell labeling, optical imaging, LED diodes, and optoelectronic technologies. Because their emission wavelengths provide the best tissue penetration, red-emitting CDs are of particular interest for applications in biomedical technologies. Current synthetic strategies enabling red-shifted emission include increasing the CD particle size (sp 2 domain) by a proper synthetic strategy and tuning the surface chemistry of CDs with suitable functional groups (e.g., carboxyl). Here we present an elegant route for preparing full-color CDs with well-controllable fluorescence at blue, green, yellow, or red wavelengths. The two-step procedure involves the synthesis of a full-color-emitting mixture of CDs from citric acid and urea in formamide followed by separation of the individual fluorescent fractions by column chromatography based on differences in CD charge. Red-emitting CDs, which had the most negative charge, were separated as the last fraction. The trend in the separation, surface charge, and red-shift of photoluminescence was caused by increasing amount of graphitic nitrogen in the CD structure, as was clearly proved by XPS, FT-IR, Raman spectroscopy, and DFT calculations. Importantly, graphitic nitrogen generates midgap states within the HOMO-LUMO gap of the undoped systems, resulting in significantly red-shifted light absorption that in turn gives rise to fluorescence at the low-energy end of the visible spectrum. The presented findings identify graphitic nitrogen as another crucial factor that can red-shift the CD photoluminescence.

A rapid microwave synthesis of nitrogen-sulfur co-doped carbon nanodots as highly sensitive and selective fluorescence probes for ascorbic acid.

PubMed

Duan, Junxia; Yu, Jie; Feng, Suling; Su, Li

2016-06-01

A ultrafast one-step microwave-assisted method was developed for the synthesis of nitrogen-sulfur co-doped carbon nanodots (N,S-CDs) by using ethylenediamine as the carbon source and sulfamic acid as the surface passivation reagent. The morphology and the properties of N,S-CDs were explored by a series of techniques, such as high-resolution transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, UV-vis absorption and fluorescence spectroscopy. The prepared N,S-CDs exhibit bright blue photoluminescence with a high fluorescence quantum yield (FLQY) up to 28%, and high stability and excellent water solubility. A N,S-CDs-based fluorescent probe was developed for sensitive detection ascorbic acid (AA) in the presence of Cu(2+), based on the mechanism that AA reduces Cu(2+) to Cu(+), then Cu(+) quenches the fluorescence of N,S-CDs through electron or energy transfer due to the interaction between Cu(+) and thiol ligand on the N,S-CDs surface. The observed linear response concentration range was from 0.057 to 4.0μM to AA with a detection limit as low as 18nM. The probe exhibited a highly selective response toward AA even in the presence of possible interfering substances, such as uric acid and citric acid. Moreover, these promising features made the sensing system used for the analysis of human serum and urine samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Efficient carbon dots/NiFe-layered double hydroxide/BiVO4 photoanodes for photoelectrochemical water splitting

NASA Astrophysics Data System (ADS)

Lv, Xiaowei; Xiao, Xin; Cao, Minglei; Bu, Yi; Wang, Chuanqing; Wang, Mingkui; Shen, Yan

2018-05-01

Modification of semiconductor photoanodes with oxygen evolution catalyst (OEC) is an effective approach for improving photoelectrochemical (PEC) water splitting efficiency. In the configuration, how to increase the activity of OEC is crucial to further improve PEC performance. Herein, a ternary photoanode system was designed to enhance PEC efficiency of photoelectrodes through introducing carbon dots (CDs), NiFe-layered double hydroxide (NiFe-LDH) nanosheets on BiVO4 particles. Systematic research shows that NiFe-LDH serves as an OEC which accelerates oxygen evolution kinetics, while the introduction of CDs can further reduce charge transfer resistance and overpotential for oxygen evolution. Under the synergistic effect of NiFe-LDH and CDs, the photocurrent and incident photon to current conversion efficiency (IPCE) of the resulting CDs/NiFe-LDH/BiVO4 photoanode is improved significantly than those of the NiFe-LDH/BiVO4 electrode. Consequently, such a ternary heterostructure could be an alternative way to further enhance PEC water splitting performance.

Cyclodextrins in delivery systems: Applications

PubMed Central

Tiwari, Gaurav; Tiwari, Ruchi; Rai, Awani K.

2010-01-01

Cyclodextrins (CDs) are a family of cyclic oligosaccharides with a hydrophilic outer surface and a lipophilic central cavity. CD molecules are relatively large with a number of hydrogen donors and acceptors and, thus in general, they do not permeate lipophilic membranes. In the pharmaceutical industry, CDs have mainly been used as complexing agents to increase aqueous solubility of poorly soluble drugs and to increase their bioavailability and stability. CDs are used in pharmaceutical applications for numerous purposes, including improving the bioavailability of drugs. Current CD-based therapeutics is described and possible future applications are discussed. CD-containing polymers are reviewed and their use in drug delivery is presented. Of specific interest is the use of CD-containing polymers to provide unique capabilities for the delivery of nucleic acids. Studies in both humans and animals have shown that CDs can be used to improve drug delivery from almost any type of drug formulation. Currently, there are approximately 30 different pharmaceutical products worldwide containing drug/CD complexes in the market. PMID:21814436

Invoking Direct Exciton-Plasmon Interactions by Catalytic Ag Deposition on Au Nanoparticles: Photoelectrochemical Bioanalysis with High Efficiency.

PubMed

Ma, Zheng-Yuan; Xu, Fei; Qin, Yu; Zhao, Wei-Wei; Xu, Jing-Juan; Chen, Hong-Yuan

2016-04-19

In this work, direct exciton-plasmon interactions (EPI) between CdS quantum dots (QDs) and Ag nanoparticles (NPs) were invoked ingeniously by catalytic Ag deposition on Au NPs for the stimulation of high efficient damping effect toward the excitonic responses in CdS QDs, on the basis of which a novel photoelectrochemical (PEC) bioanalytical format was achieved for sensitive microRNA detection. Specifically, upon the configurational change from the hairpin probe DNA to the "Y"-shaped ternary conjugate consisting of the original probe DNA, assistant DNA, and the target microRNA, the alkaline phosphatase (ALP) catalytic chemistry would then trigger the transition of the interparticle interplay from the CdS QDs-Au NPs to the CdS QDs-Ag NPs systems for the microRNA detection due to the dependence of the photocurrent quenching on the target concentration. This work not only provided a unique method for EPI generation among the PEC nanosystems but also offered a versatile and general protocol for future PEC bioanalysis development.

How Documentalists Update SIMBAD

NASA Astrophysics Data System (ADS)

Buga, M.; Bot, C.; Brouty, M.; Bruneau, C.; Brunet, C.; Cambresy, L.; Eisele, A.; Genova, F.; Lesteven, S.; Loup, C.; Neuville, M.; Oberto, A.; Ochsenbein, F.; Perret, E.; Siebert, A.; Son, E.; Vannier, P.; Vollmer, B.; Vonflie, P.; Wenger, M.; Woelfel, F.

2015-04-01

The Strasbourg astronomical Data Center (CDS) was created in 1972 and has had a major role in astronomy for more than forty years. CDS develops a service called SIMBAD that provides basic data, cross-identifications, bibliography, and measurements for astronomical objects outside the solar system. It brings to the scientific community an added value to content which is updated daily by a team of documentalists working together in close collaboration with astronomers and IT specialists. We explain how the CDS staff updates SIMBAD with object citations in the main astronomical journals, as well as with astronomical data and measurements. We also explain how the identification is made between the objects found in the literature and those already existing in SIMBAD. We show the steps followed by the documentalist team to update the database using different tools developed at CDS, like the sky visualizer Aladin, and the large catalogues and survey database VizieR. As a direct result of this teamwork, SIMBAD integrates almost 10.000 bibliographic references per year. The service receives more than 400.000 queries per day.

Nitrogen and sulfur co-doped carbon dots with strong blue luminescence

NASA Astrophysics Data System (ADS)

Ding, Hui; Wei, Ji-Shi; Xiong, Huan-Ming

2014-10-01

Sulfur-doped carbon dots (S-CDs) with a quantum yield (QY) of 5.5% and nitrogen, sulfur co-doped carbon dots (N,S-CDs) with a QY of 54.4% were synthesized, respectively, via the same hydrothermal route using α-lipoic acid as the carbon source. The obtained S-CDs and N,S-CDs had similar sizes but different optical features. The QY of N,S-CDs was gradually enhanced when extending the reaction time to increase the nitrogen content. After careful characterization of these CDs, the doped nitrogen element was believed to be in the form of C&z.dbd;N and C-N bonds which enhanced the fluorescence efficiency significantly. Meanwhile, the co-doped sulfur element was found to be synergistic for nitrogen doping in N,S-CDs. The optimal N,S-CDs were successfully employed as good multicolor cell imaging probes due to their fine dispersion in water, excitation-dependent emission, excellent fluorescence stability and low toxicity. Besides, such N,S-CDs showed a wide detection range and excellent accuracy as fluorescent sensors for Fe3+ ions.Sulfur-doped carbon dots (S-CDs) with a quantum yield (QY) of 5.5% and nitrogen, sulfur co-doped carbon dots (N,S-CDs) with a QY of 54.4% were synthesized, respectively, via the same hydrothermal route using α-lipoic acid as the carbon source. The obtained S-CDs and N,S-CDs had similar sizes but different optical features. The QY of N,S-CDs was gradually enhanced when extending the reaction time to increase the nitrogen content. After careful characterization of these CDs, the doped nitrogen element was believed to be in the form of C&z.dbd;N and C-N bonds which enhanced the fluorescence efficiency significantly. Meanwhile, the co-doped sulfur element was found to be synergistic for nitrogen doping in N,S-CDs. The optimal N,S-CDs were successfully employed as good multicolor cell imaging probes due to their fine dispersion in water, excitation-dependent emission, excellent fluorescence stability and low toxicity. Besides, such N,S-CDs showed a wide detection range and excellent accuracy as fluorescent sensors for Fe3+ ions. Electronic supplementary information (ESI) available: Experimental details and comparable characterization of three kinds of CDs. See DOI: 10.1039/c4nr04267k

Phosphorene Co-catalyst Advancing Highly Efficient Visible-Light Photocatalytic Hydrogen Production.

PubMed

Ran, Jingrun; Zhu, Bicheng; Qiao, Shi-Zhang

2017-08-21

Transitional metals are widely used as co-catalysts boosting photocatalytic H 2 production. However, metal-based co-catalysts suffer from high cost, limited abundance and detrimental environment impact. To date, metal-free co-catalyst is rarely reported. Here we for the first time utilized density functional calculations to guide the application of phosphorene as a high-efficiency metal-free co-catalyst for CdS, Zn 0.8 Cd 0.2 S or ZnS. Particularly, phosphorene modified CdS shows a high apparent quantum yield of 34.7 % at 420 nm. This outstanding activity arises from the strong electronic coupling between phosphorene and CdS, as well as the favorable band structure, high charge mobility and massive active sites of phosphorene, supported by computations and advanced characterizations, for example, synchrotron-based X-ray absorption near edge spectroscopy. This work brings new opportunities to prepare highly-active, cheap and green photocatalysts. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Architecture Design of Healthcare Software-as-a-Service Platform for Cloud-Based Clinical Decision Support Service.

PubMed

Oh, Sungyoung; Cha, Jieun; Ji, Myungkyu; Kang, Hyekyung; Kim, Seok; Heo, Eunyoung; Han, Jong Soo; Kang, Hyunggoo; Chae, Hoseok; Hwang, Hee; Yoo, Sooyoung

2015-04-01

To design a cloud computing-based Healthcare Software-as-a-Service (SaaS) Platform (HSP) for delivering healthcare information services with low cost, high clinical value, and high usability. We analyzed the architecture requirements of an HSP, including the interface, business services, cloud SaaS, quality attributes, privacy and security, and multi-lingual capacity. For cloud-based SaaS services, we focused on Clinical Decision Service (CDS) content services, basic functional services, and mobile services. Microsoft's Azure cloud computing for Infrastructure-as-a-Service (IaaS) and Platform-as-a-Service (PaaS) was used. The functional and software views of an HSP were designed in a layered architecture. External systems can be interfaced with the HSP using SOAP and REST/JSON. The multi-tenancy model of the HSP was designed as a shared database, with a separate schema for each tenant through a single application, although healthcare data can be physically located on a cloud or in a hospital, depending on regulations. The CDS services were categorized into rule-based services for medications, alert registration services, and knowledge services. We expect that cloud-based HSPs will allow small and mid-sized hospitals, in addition to large-sized hospitals, to adopt information infrastructures and health information technology with low system operation and maintenance costs.

Evaluation of children with lymphatic malformations of the head and neck using the Cologne Disease Score.

PubMed

Wiegand, Susanne; Eivazi, Behfar; Zimmermann, Annette P; Sesterhenn, Andreas M; Werner, Jochen A

2009-07-01

To assess the disease-related impairments of children with lymphatic malformations of the head and neck and their changes after therapy using the Cologne Disease Score (CDS). 29 children with lymphatic malformations of the head and neck were evaluated regarding their symptoms before and after therapy using the CDS. The Wilcoxon test for dependent groups was used to compare the CDS at initial visit before treatment and last visit after treatment. The CDS of patients belonging to the moderate (initial CDS: more than eight points) and advanced disease group (initial CDS: five, six or seven points) significantly increased after therapy while the patients in the severe disease group (initial CDS: lower than four points) showed no significant improvement of CDS. Patients with stage IV and especially stage V lymphatic malformations according to de Serres showed considerably lower pre- and posttherapeutic CDS levels than those of stage I and II. The visual impairment is not mapped by the CDS, therefore item vision should be added to the CDS to make an evaluation of all lymphatic malformations of the head and neck possible. The present series could show that especially patients with a moderate or advanced disease according to the CDS may profit from therapeutic interventions.

Design of a Hole Trapping Ligand

DOE PAGES

La Croix, Andrew D.; O’Hara, Andrew; Reid, Kemar R.; ...

2017-01-18

A new ligand that covalently attaches to the surface of colloidal CdSe/ CdS nanorods and can simultaneously chelate a molecular metal center is described. The dithiocarbamate$-$bipyridine ligand system facilitates hole transfer through energetic overlap at the inorganic$-$organic interface and conjugation through the organic ligand to a chelated metal center. Density functional theory calculations show that the coordination of the free ligand to a CdS surface causes the formation of two hybridized molecular states that lie in the band gap of CdS. The further chelation of Fe(II) to the bipyridine moiety causes the presence of seven midgap states. Hole transfer frommore » the CdS valence band to the midgap states is dipole allowed and occurs at a faster rate than what is experimentally known for the CdSe/CdS band-edge radiative recombination. In the case of the ligand bound with iron, a two-step process emerges that places the hole on the iron, again at rates much faster than band gap recombination. The system was experimentally assembled and characterized via UV$-$vis absorbance spectroscopy, fluorescence spectroscopy, time-resolved photoluminescence spectroscopy, and energy dispersive X-ray spectroscopy. Lastly, theoretically predicted red shifts in absorbance were observed experimentally, as well as the expected quench in photoluminescence and lifetimes in time-resolved photoluminescence« less

Design of a Hole Trapping Ligand

DOE Office of Scientific and Technical Information (OSTI.GOV)

La Croix, Andrew D.; O’Hara, Andrew; Reid, Kemar R.

A new ligand that covalently attaches to the surface of colloidal CdSe/ CdS nanorods and can simultaneously chelate a molecular metal center is described. The dithiocarbamate$-$bipyridine ligand system facilitates hole transfer through energetic overlap at the inorganic$-$organic interface and conjugation through the organic ligand to a chelated metal center. Density functional theory calculations show that the coordination of the free ligand to a CdS surface causes the formation of two hybridized molecular states that lie in the band gap of CdS. The further chelation of Fe(II) to the bipyridine moiety causes the presence of seven midgap states. Hole transfer frommore » the CdS valence band to the midgap states is dipole allowed and occurs at a faster rate than what is experimentally known for the CdSe/CdS band-edge radiative recombination. In the case of the ligand bound with iron, a two-step process emerges that places the hole on the iron, again at rates much faster than band gap recombination. The system was experimentally assembled and characterized via UV$-$vis absorbance spectroscopy, fluorescence spectroscopy, time-resolved photoluminescence spectroscopy, and energy dispersive X-ray spectroscopy. Lastly, theoretically predicted red shifts in absorbance were observed experimentally, as well as the expected quench in photoluminescence and lifetimes in time-resolved photoluminescence« less

One pot synthesis of highly luminescent polyethylene glycol anchored carbon dots functionalized with a nuclear localization signal peptide for cell nucleus imaging.

PubMed

Yang, Lei; Jiang, Weihua; Qiu, Lipeng; Jiang, Xuewei; Zuo, Daiying; Wang, Dongkai; Yang, Li

2015-04-14

Strong blue fluorescent polyethylene glycol (PEG) anchored carbon nitride dots (CDs@PEG) with a high quantum yield (QY) of 75.8% have been synthesized by a one step hydrothermal treatment. CDs with a diameter of ca. 6 nm are well dispersed in water and present a graphite-like structure. Photoluminescence (PL) studies reveal that CDs display excitation-dependent behavior and are stable under various test conditions. Based on the as-prepared CDs, we designed novel cell nucleus targeting imaging carbon dots functionalized with a nuclear localization signal (NLS) peptide. The favourable biocompatibilities of CDs and NLS modified CDs (NLS-CDs) are confirmed by in vitro cytotoxicity assays. Importantly, intracellular localization experiments in MCF7 and A549 cells demonstrate that NLS-CDs could be internalized in the nucleus and show blue light, which indicates that CDs may serve as cell nucleus imaging probes.

Fabrication of CDs/CdS-TiO2 ternary nano-composites for photocatalytic degradation of benzene and toluene under visible light irradiation

NASA Astrophysics Data System (ADS)

Wang, Meng; Hua, Jianhao; Yang, Yaling

2018-06-01

An efficient cadmium sulfide quantum-dots (CdS QDs) and carbon dots (CDs) modified TiO2 photocatalyst (CdS/CDs-TiO2) was successfully fabricated. The as-prepared ternary nano-composites simultaneously improved the photo-corrosion of CdS and amplified its photocatalytic activity. The introduction of CdS QDs and CDs could enhance more absorbance of light, prevent the undesirable electron/hole recombination, and promote charge separation, which was important for the continuous formation of rad OH and rad O2- radicals. When the optimal mass ratio of CdS QDs to CDs was 3:1, above 90% degradation efficiencies were achieved for benzene within 1 h and toluene in 2 h, while that of pure TiO2 (P25), CdS QDs-TiO2, CDs-TiO2 nano-composites was around 15%. Owing to the symmetric structure and conjugation of methyl with benzene ring, the degradation of toluene was more difficult than benzene to carry on. The new fabricated nano-composites showed good prospective application of cleaning up refractory pollutants and the resource utilization.

Highly Efficient Photocatalytic Hydrogen Production of Flower-like Cadmium Sulfide Decorated by Histidine

PubMed Central

Wang, Qizhao; Lian, Juhong; Li, Jiajia; Wang, Rongfang; Huang, Haohao; Su, Bitao; Lei, Ziqiang

2015-01-01

Morphology-controlled synthesis of CdS can significantly enhance the efficiency of its photocatalytic hydrogen production. In this study, a novel three-dimensional (3D) flower-like CdS is synthesized via a facile template-free hydrothermal process using Cd(NO3)2•4H2O and thiourea as precursors and L-Histidine as a chelating agent. The morphology, crystal phase, and photoelectrochemical performance of the flower-like CdS and pure CdS nanocrystals are carefully investigated via various characterizations. Superior photocatalytic activity relative to that of pure CdS is observed on the flower-like CdS photocatalyst under visible light irradiation, which is nearly 13 times of pure CdS. On the basis of the results from SEM studies and our analysis, a growth mechanism of flower-like CdS is proposed by capturing the shape evolution. The imidazole ring of L-Histidine captures the Cd ions from the solution, and prevents the growth of the CdS nanoparticles. Furthermore, the photocatalytic contrast experiments illustrate that the as-synthesized flower-like CdS with L-Histidine is more stable than CdS without L-Histidine in the hydrogen generation. PMID:26337119

Highly Efficient Photocatalytic Hydrogen Production of Flower-like Cadmium Sulfide Decorated by Histidine

NASA Astrophysics Data System (ADS)

Wang, Qizhao; Lian, Juhong; Li, Jiajia; Wang, Rongfang; Huang, Haohao; Su, Bitao; Lei, Ziqiang

2015-09-01

Morphology-controlled synthesis of CdS can significantly enhance the efficiency of its photocatalytic hydrogen production. In this study, a novel three-dimensional (3D) flower-like CdS is synthesized via a facile template-free hydrothermal process using Cd(NO3)2•4H2O and thiourea as precursors and L-Histidine as a chelating agent. The morphology, crystal phase, and photoelectrochemical performance of the flower-like CdS and pure CdS nanocrystals are carefully investigated via various characterizations. Superior photocatalytic activity relative to that of pure CdS is observed on the flower-like CdS photocatalyst under visible light irradiation, which is nearly 13 times of pure CdS. On the basis of the results from SEM studies and our analysis, a growth mechanism of flower-like CdS is proposed by capturing the shape evolution. The imidazole ring of L-Histidine captures the Cd ions from the solution, and prevents the growth of the CdS nanoparticles. Furthermore, the photocatalytic contrast experiments illustrate that the as-synthesized flower-like CdS with L-Histidine is more stable than CdS without L-Histidine in the hydrogen generation.

Highly Efficient Photocatalytic Hydrogen Production of Flower-like Cadmium Sulfide Decorated by Histidine.

PubMed

Wang, Qizhao; Lian, Juhong; Li, Jiajia; Wang, Rongfang; Huang, Haohao; Su, Bitao; Lei, Ziqiang

2015-09-04

Morphology-controlled synthesis of CdS can significantly enhance the efficiency of its photocatalytic hydrogen production. In this study, a novel three-dimensional (3D) flower-like CdS is synthesized via a facile template-free hydrothermal process using Cd(NO3)2•4H2O and thiourea as precursors and L-Histidine as a chelating agent. The morphology, crystal phase, and photoelectrochemical performance of the flower-like CdS and pure CdS nanocrystals are carefully investigated via various characterizations. Superior photocatalytic activity relative to that of pure CdS is observed on the flower-like CdS photocatalyst under visible light irradiation, which is nearly 13 times of pure CdS. On the basis of the results from SEM studies and our analysis, a growth mechanism of flower-like CdS is proposed by capturing the shape evolution. The imidazole ring of L-Histidine captures the Cd ions from the solution, and prevents the growth of the CdS nanoparticles. Furthermore, the photocatalytic contrast experiments illustrate that the as-synthesized flower-like CdS with L-Histidine is more stable than CdS without L-Histidine in the hydrogen generation.

Electrospinning of nanofibers from non-polymeric systems: polymer-free nanofibers from cyclodextrin derivatives

NASA Astrophysics Data System (ADS)

Celebioglu, Asli; Uyar, Tamer

2012-01-01

High molecular weight polymers and high polymer concentrations are desirable for the electrospinning of nanofibers since polymer chain entanglements and overlapping are important for uniform fiber formation. Hence, the electrospinning of nanofibers from non-polymeric systems such as cyclodextrins (CDs) is quite a challenge since CDs are cyclic oligosaccharides. Nevertheless, in this study, we have successfully achieved the electrospinning of nanofibers from chemically modified CDs without using a carrier polymer matrix. Polymer-free nanofibers were electrospun from three different CD derivatives, hydroxypropyl-β-cyclodextrin (HPβCD), hydroxypropyl-γ-cyclodextrin (HPγCD) and methyl-β-cyclodextrin (MβCD) in three different solvent systems, water, dimethylformamide (DMF) and dimethylacetamide (DMAc). We observed that the electrospinning of these CDs is quite similar to polymeric systems in which the solvent type, the solution concentration and the solution conductivity are some of the key factors for obtaining uniform nanofibers. Dynamic light scattering (DLS) measurements indicated that the presence of considerable CD aggregates and the very high solution viscosity were playing a key role for attaining nanofibers from CD derivatives without the use of any polymeric carrier. The electrospinning of CD solutions containing urea yielded no fibers but only beads or splashes since urea caused a notable destruction of the self-associated CD aggregates in their concentrated solutions. The structural, thermal and mechanical characteristics of the CD nanofibers were also investigated. Although the CD derivatives are amorphous small molecules, interestingly, we observed that these electrospun CD nanofibers/nanowebs have shown some mechanical integrity by which they can be easily handled and folded as a free standing material.

Excellent photocatalytic hydrogen production over CdS nanorods via using noble metal-free copper molybdenum sulfide (Cu2MoS4) nanosheets as co-catalysts

NASA Astrophysics Data System (ADS)

Hong, Sangyeob; Kumar, D. Praveen; Reddy, D. Amaranatha; Choi, Jiha; Kim, Tae Kyu

2017-02-01

Charge carrier recombination and durability issues are major problems in photocatalytic hydrogen (H2) evolution processes. Thus, there is a very important necessitate to extend an efficient photocatalyst to control charge-carrier dynamics in the photocatalytic system. We have developed copper molybdenum sulfide (Cu2MoS4) nanosheets as co-catalysts with CdS nanorods for controlling charge carriers without recombination for use in photocatalytic H2 evolution under simulated solar light irradiation. Effective control and utilization of charge carriers are possible by loading Cu2MoS4 nanosheets onto the CdS nanorods. The loading compensates for the restrictions of CdS, and stimulated synergistic effects, such as efficient photoexcited charge separation, lead to an improvement in photostability because of the layered structure of the Cu2MoS4nanosheets. These layered Cu2MoS4 nanosheets have emerged as novel and active replacements for precious noble metal co-catalysts in photocatalytic H2 production by water splitting. We have obtained superior H2 production rates by using Cu2MoS4 loaded CdS nanorods. The physicochemical properties of the composites are analyzed by diverse characterization techniques.

Studying the Vendor Perspective on Clinical Decision Support

PubMed Central

Ash, Joan S.; Sittig, Dean F.; McMullen, Carmit K.; McCormack, James L.; Wright, Adam; Bunce, Arwen; Wasserman, Joseph; Mohan, Vishnu; Cohen, Deborah J.; Shapiro, Michael; Middleton, Blackford

2011-01-01

In prior work, using a Rapid Assessment Process (RAP), we have investigated clinical decision support (CDS) in ambulatory clinics and hospitals. We realized that individuals in these settings provide only one perspective related to the CDS landscape, which also includes content vendors and electronic health record (EHR) vendors. To discover content vendors’ perspectives and their perceived challenges, we modified RAP for industrial settings. We describe how we employed RAP, and show its utility by describing two illustrative themes. We found that while the content vendors believe they provide unique much-needed services, the amount of labor involved in content development is underestimated by others. We also found that the content vendors believe their products are resources to be used by practitioners, so they are somewhat protected from liability issues. To promote adequate understanding about these issues, we recommend a “three way conversation” among content vendors, EHR vendors, and user organizations. PMID:22195058

Decision support from local data: creating adaptive order menus from past clinician behavior.

PubMed

Klann, Jeffrey G; Szolovits, Peter; Downs, Stephen M; Schadow, Gunther

2014-04-01

Reducing care variability through guidelines has significantly benefited patients. Nonetheless, guideline-based Clinical Decision Support (CDS) systems are not widely implemented or used, are frequently out-of-date, and cannot address complex care for which guidelines do not exist. Here, we develop and evaluate a complementary approach - using Bayesian Network (BN) learning to generate adaptive, context-specific treatment menus based on local order-entry data. These menus can be used as a draft for expert review, in order to minimize development time for local decision support content. This is in keeping with the vision outlined in the US Health Information Technology Strategic Plan, which describes a healthcare system that learns from itself. We used the Greedy Equivalence Search algorithm to learn four 50-node domain-specific BNs from 11,344 encounters: abdominal pain in the emergency department, inpatient pregnancy, hypertension in the Urgent Visit Clinic, and altered mental state in the intensive care unit. We developed a system to produce situation-specific, rank-ordered treatment menus from these networks. We evaluated this system with a hospital-simulation methodology and computed Area Under the Receiver-Operator Curve (AUC) and average menu position at time of selection. We also compared this system with a similar association-rule-mining approach. A short order menu on average contained the next order (weighted average length 3.91-5.83 items). Overall predictive ability was good: average AUC above 0.9 for 25% of order types and overall average AUC .714-.844 (depending on domain). However, AUC had high variance (.50-.99). Higher AUC correlated with tighter clusters and more connections in the graphs, indicating importance of appropriate contextual data. Comparison with an Association Rule Mining approach showed similar performance for only the most common orders with dramatic divergence as orders are less frequent. This study demonstrates that local clinical knowledge can be extracted from treatment data for decision support. This approach is appealing because: it reflects local standards; it uses data already being captured; and it produces human-readable treatment-diagnosis networks that could be curated by a human expert to reduce workload in developing localized CDS content. The BN methodology captured transitive associations and co-varying relationships, which existing approaches do not. It also performs better as orders become less frequent and require more context. This system is a step forward in harnessing local, empirical data to enhance decision support. Copyright © 2013 Elsevier Inc. All rights reserved.

Decision Support from Local Data: Creating Adaptive Order Menus from Past Clinician Behavior

PubMed Central

Klann, Jeffrey G.; Szolovits, Peter; Downs, Stephen; Schadow, Gunther

2014-01-01

Objective Reducing care variability through guidelines has significantly benefited patients. Nonetheless, guideline-based clinical decision support (CDS) systems are not widely implemented or used, are frequently out-of-date, and cannot address complex care for which guidelines do not exist. Here, we develop and evaluate a complementary approach - using Bayesian network (BN) learning to generate adaptive, context-specific treatment menus based on local order-entry data. These menus can be used as a draft for expert review, in order to minimize development time for local decision support content. This is in keeping with the vision outlined in the US Health Information Technology Strategic Plan, which describes a healthcare system that learns from itself. Materials and Methods We used the Greedy Equivalence Search algorithm to learn four 50-node domain-specific BNs from 11,344 encounters: abdominal pain in the emergency department, inpatient pregnancy, hypertension in the urgent visit clinic, and altered mental state in the intensive care unit. We developed a system to produce situation-specific, rank-ordered treatment menus from these networks. We evaluated this system with a hospital-simulation methodology and computed Area Under the Receiver-Operator Curve (AUC) and average menu position at time of selection. We also compared this system with a similar association-rule-mining approach. Results A short order menu on average contained the next order (weighted average length 3.91–5.83 items). Overall predictive ability was good: average AUC above 0.9 for 25% of order types and overall average AUC .714–.844 (depending on domain). However, AUC had high variance (.50–.99). Higher AUC correlated with tighter clusters and more connections in the graphs, indicating importance of appropriate contextual data. Comparison with an association rule mining approach showed similar performance for only the most common orders with dramatic divergence as orders are less frequent. Discussion and Conclusion This study demonstrates that local clinical knowledge can be extracted from treatment data for decision support. This approach is appealing because: it reflects local standards; it uses data already being captured; and it produces human-readable treatment-diagnosis networks that could be curated by a human expert to reduce workload in developing localized CDS content. The BN methodology captured transitive associations and co-varying relationships, which existing approaches do not. It also performs better as orders become less frequent and require more context. This system is a step forward in harnessing local, empirical data to enhance decision support. PMID:24355978

Efficient synthesis of highly fluorescent nitrogen-doped carbon dots for cell imaging using unripe fruit extract of Prunus mume

NASA Astrophysics Data System (ADS)

Atchudan, Raji; Edison, Thomas Nesakumar Jebakumar Immanuel; Sethuraman, Mathur Gopalakrishnan; Lee, Yong Rok

2016-10-01

Highly fluorescent nitrogen-doped carbon dots (N-CDs) were synthesized using the extract of unripe Prunus mume (P. mume) fruit by a simple one step hydrothermal-carbonization method. The N-CDs were synthesized at different pH ranges, 2.3, 5, 7, and 9. The pH of the P. mume extract was adjusted using an aqueous ammonia solution (25%). The optical properties of N-CDs were examined by UV-vis and fluorescence spectroscopy. The N-CDs synthesized at pH 9 emitted high fluorescence intensity compared to other obtained N-CDs. The N-CDs synthesized at pH 9 was further characterized by high resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and Fourier transform-infra red (FT-IR) spectroscopy. HR-TEM showed that the average size of the synthesized N-CDs was approximately 9 nm and the interlayer distance was 0.21 nm, which was validated by XRD. The graphitic nature of the synthesized N-CDs were confirmed by Raman spectroscopy. XPS and FT-IR spectroscopy confirmed the doping of the nitrogen moiety over the synthesized CDs. The synthesized nitrogen doped CDs (N-CDs) were low toxicity and were used as a staining probe for fluorescence cell imaging.

Functionalized CdS quantum dots-based luminescence probe for detection of heavy and transition metal ions in aqueous solution.

PubMed

Chen, Jinlong; Zheng, Aifang; Gao, Yingchun; He, Chiyang; Wu, Genhua; Chen, Youcun; Kai, Xiaoming; Zhu, Changqing

2008-03-01

Strong luminescence CdS quantum dots (QDs) have been prepared and modified with l-cysteine by a facile seeds-assistant technique in water. They are water-soluble and highly stable in aqueous solution. CdS QDs evaluated as a luminescence probe for heavy and transition metal (HTM) ions in aqueous solution was systematically studied. Five HTM ions such as silver(I) ion, copper(II) ion, mercury(II) ion, cobalt(II) ion, and nickel(II) ion significantly influence the photophysics of the emission from the functionalized CdS QDs. Experiment results showed that the fluorescence emission from CdS QDs was enhanced significantly by silver ion without any spectral shift, while several other bivalent HTM ions, such as Hg(2+), Cu(2+), Co(2+), and Ni(2+), exhibited effective optical quenching effect on QDs. Moreover, an obvious red-shift of emission band was observed in the quenching of CdS QDs for Hg(2+) and Cu(2+) ions. Under the optimal conditions, the response was linearly proportional to the concentration of Ag(+) ion ranging from 1.25 x 10(-7) to 5.0 x 10(-6)molL(-1) with a detection limit of 2.0 x 10(-8)molL(-1). The concentration dependence of the quenching effect on functionalized QDs for the other four HTM ions could be well described by typical Stern-Volmer equation, with the linear response of CdS QDs emission proportional to the concentration ranging from 1.50 x 10(-8) to 7.50 x 10(-7)molL(-1) for Hg(2+) ion, 3.0 x 10(-7) to 1.0 x 10(-5)molL(-1) for Ni(2+) ion, 4.59 x 10(-8) to 2.295 x 10(-6)molL(-1) for Cu(2+) ion, and 1.20 x 10(-7) to 6.0 x 10(-6)molL(-1) Co(2+) ion, respectively. Based on the distinct optical properties of CdS QDs system with the five HTM ions, and the relatively wide linear range and rapid response to HTM ions, CdS QDs can be developed as a potential identified luminescence probe for familiar HTM ions detection in aqueous solution.

A bifacial quantum dot-sensitized solar cell with all-cadmium sulfide photoanode

NASA Astrophysics Data System (ADS)

Ma, Chunqing; Tang, Qunwei; Liu, Danyang; Zhao, Zhiyuan; He, Benlin; Chen, Haiyan; Yu, Liangmin

2015-02-01

Pursuit of a high power conversion efficiency and reduction of electricity-generation cost has been a persistent objective for quantum dot-sensitized solar cells (QDSSCs). We present here the fabrication of a QDSSC comprising a nanoflower-structured CdS anode, a liquid electrolyte having S2-/Sn2- redox couples, and a transparent CoSe counter electrode. Nanoflower-structured CdS anodes are prepared by a successive ionic layer adsorption and reaction (SILAR) method and subsequently hydrothermal strategy free of any surfactant or template. The CdS nanoparticles synthesized by a SILAR method act as "seed crystal" for growth of CdS nanoflowers. The average electron lifetime is markedly elevated in nanoflower-structured CdS anode in comparison with CdS nanoparticle or nanoporous CdS microsphere anode. Herein, we study the effect of synthesis method on CdS morphology and solar cell's photovoltaic performance, showing a power conversion efficiency of 1.67% and 1.17% for nanoflower-structured CdS QDSSC under front and rear irradiations, respectively.

Biosynthesis of fluorescent CdS nanocrystals with semiconductor properties: Comparison of microbial and plant production systems.

PubMed

Al-Shalabi, Zahwa; Doran, Pauline M

2016-04-10

This study investigated fission yeast (Schizosaccharomyces pombe) and hairy roots of tomato (Solanum lycopersicum) as in vitro production vehicles for biological synthesis of CdS quantum dots. Cd added during the mid-growth phase of the cultures was detoxified within the biomass into inorganic sulphide-containing complexes with the quantum confinement properties of semiconductor nanocrystals. Significant differences were found between the two host systems in terms of nanoparticle production kinetics, yield and quality. The much slower growth rate of hairy roots compared with yeast is a disadvantage for commercial scaled-up production. Nanoparticle extraction from the biomass was less effective for the roots: 19% of the Cd present in the hairy roots was recovered after extraction compared with 34% for the yeast. The overall yield of CdS quantum dots was also lower for the roots: relative to the amount of Cd taken up into the biomass, 8.5% was recovered in yeast gel filtration fractions exhibiting quantum dot properties whereas the result for hairy roots was only 0.99%. Yeast-produced CdS crystallites were somewhat smaller with diameters of approximately 2-6 nm compared with those of 4-10nm obtained from the roots. The average ratio of inorganic sulphide to Cd for the purified and size-fractionated particles was 0.44 for the yeast and 1.6 for the hairy roots. Despite the limitations associated with hairy roots in terms of culture kinetics and product yield, this system produced CdS nanoparticles with enhanced photostability and 3.7-13-fold higher fluorescence quantum efficiency compared with those generated by yeast. This work demonstrates that the choice of cellular host can have a significant effect on nanoparticle functional properties as well as on the bioprocessing aspects of biological quantum dot synthesis. Copyright © 2016 Elsevier B.V. All rights reserved.

Dynamic Modeling of Process Technologies for Closed-Loop Water Recovery Systems

NASA Technical Reports Server (NTRS)

Allada, Rama Kumar; Lange, Kevin; Anderson, Molly

2011-01-01

Detailed chemical process simulations are a useful tool in designing and optimizing complex systems and architectures for human life support. Dynamic and steady-state models of these systems help contrast the interactions of various operating parameters and hardware designs, which become extremely useful in trade-study analyses. NASA s Exploration Life Support technology development project recently made use of such models to compliment a series of tests on different waste water distillation systems. This paper presents dynamic simulations of chemical process for primary processor technologies including: the Cascade Distillation System (CDS), the Vapor Compression Distillation (VCD) system, the Wiped-Film Rotating Disk (WFRD), and post-distillation water polishing processes such as the Volatiles Removal Assembly (VRA) that were developed using the Aspen Custom Modeler and Aspen Plus process simulation tools. The results expand upon previous work for water recovery technology models and emphasize dynamic process modeling and results. The paper discusses system design, modeling details, and model results for each technology and presents some comparisons between the model results and available test data. Following these initial comparisons, some general conclusions and forward work are discussed.

Closed depressions in the European loess belt - Natural or anthropogenic origin?

NASA Astrophysics Data System (ADS)

Kołodyńska-Gawrysiak, Renata; Poesen, Jean

2017-07-01

Closed depressions (CDs) are typical geomorphological features of the loess belt in Europe. CDs have been reported in several regions of the European loess belt, where they are described as hollows, mardeles, wymoki, crovuri, bludtsa and zapadiny. The natural and anthropogenic origins of CDs are debated in literature. Moreover, no comprehensive review of the geomorphic properties or the evolution of these depressions exists. Therefore this paper reviews the characteristics of CDs in the European loess belt and attempts to better understand their genesis based on detailed case studies. The main morphometric features as well as sediment deposits within CDs in several sub-regions of Europe were analysed and compared. Morphometric properties of CDs from the West European and East European loess belt were investigated through a comparison of CDs from two representative regions, i.e. East Poland and Central Belgium. In both study areas, CDs under cropland are similar. However, a comparison of morphological features of CDs under forest, revealed clear differences, suggesting a different origin of CDs from both regions. Infilled sediments in CDs show various litho-genetical features in different regions of the European loess belt. The morphometric features, ages and stratigraphy of infillings clearly indicate that both anthropogenic and natural processes have shaped these landforms within the loess belt of Europe. CDs observed in Eastern Europe may have a very different origin than those documented in Western Europe. Detailed analysis of CDs in Poland and in neighbouring regions of East Europe, suggest that CDs are natural landforms: thermokarst, deflation and dissolution of loess are reported as probable genetic processes. In contrast, several studies in Western Europe indicate a dominant anthropogenic origin (i.e. digging of calcareous loess or marls, bomb and mining craters, collapse of underground limestone quarries), although CDs formed by natural processes (i.e. piping, dissolution of limestone and salt lenses below the loess cover) are reported as well. CDs act as important archives, allowing one to reconstruct both natural and anthropogenic processes operating in the past. As CDs store most sediments eroded within their catchment they provide ideal sediment traps to assess long-term erosion rates in these environments which have hitherto been under-researched. More research is needed to unravel the genesis and evolution of these depressions to better understand the importance of the Late Glacial and Holocene stages for the morphogenesis of the loess belt in Europe.

LAMDA at TREC CDS track 2015: Clinical Decision Support Track

DTIC Science & Technology

2015-11-20

outperforms all the other vector space models supported by Elasticsearch. MetaMap is the online tool that maps biomedical text to the Metathesaurus, and...cases. The medical knowledge consists of 700,000 biomedical documents supported by the PubMed Central [3] which is online digital database freely...Science Research Program through the National Research Foundation (NRF) of Korea funded by the Ministry of Science, ICT , and Future Planning (MSIP

Obtaining electrostatically bound CdS-SiO2 aggregates from electrophoretic concentrates of CdS nanoparticles

NASA Astrophysics Data System (ADS)

Bulavchenko, A. I.; Sap'yanik, A. A.; Demidova, M. G.; Rakhmanova, M. I.; Popovetskii, P. S.

2015-05-01

Nonaqueous electrophoresis reveals that the electrokinetic potential of CdS nanoparticles increases slightly (85-120 mV) along with the concentration (0-5 × 10-3 M) of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) in n-decane, while negatively charged SiO2 particles acquire positive charge (switching from -75 up to +135 mV). The energies of interparticle interactions in CdS-CdS and CdS-SiO2 systems are calculated from these parameters and the literature values of the Hamaker constants according to the Deryaguin-Landau-Verwey-Overbeek (DLVO) theory. It is concluded that the presence of a minimum (2.5 k B T) on the potential dependences of the CdS-SiO2 system indicates the formation of CdS-SiO2 aggregates electrostatically bound by heterocoagulation at low concentrations of AOT. The luminescent properties of the obtained ultrafine CdS-SiO2 powders depend on the CdS content.

Adverse childhood events and current depressive symptoms among women in Hawaii: 2010 BRFSS, Hawaii.

PubMed

Remigio-Baker, Rosemay A; Hayes, Donald K; Reyes-Salvail, Florentina

2014-12-01

Research on the association between adverse childhood events (ACEs) and depression among women in Hawaii is scarce. ACEs have been linked to unfavorable health behaviors such as smoking and binge drinking which are more prevalent in the state compared to the US overall. The concomitant presence of ACEs with smoking or binge drinking may explain the excess depression prevalence in Hawaii compared to the national average. Using data of women residing in the state (2010 Hawaii Behavioral Risk Factor Surveillance System Survey), we examined the association between ACEs count or type (household dysfunction and physical, verbal and sexual abuse) and current depressive symptoms (CDS), in addition to modification by current smoking status (smoked >100 cigarettes in a lifetime and currently smoke) and binge drinking (consumed ≥4 alcoholic beverage within the past month and in ≥1 occasion(s)). Evaluation of ACEs before age 18 consisted of 11 indicators. Eight indicators of the Patient Health Questionnaire (PHQ-8) were used to assess CDS. All analyses utilized logistic regression taking into account sampling design. The odds ratio of having CDS between those with versus without ACEs increased per increasing number of ACEs (1 ACE: OR = 2.11, CI = 1.16-3.81; 2 ACEs: OR = 2.90, CI = 1.51-5.58; 3 or 4 ACEs: OR = 3.94, CI = 2.13-7.32; 5+ ACEs: OR = 4.04, CI = 2.26-7.22). Household dysfunction (OR = 2.10, CI = 1.37-3.23), physical abuse (OR = 1.67, CI = 1.08-2.59), verbal abuse (OR = 3.21, CI = 2.03-5.09) and sexual abuse (OR = 1.68, CI = 1.04-2.71) were all positively associated with CDS. Verbal abuse had the strongest magnitude of association. Neither current smoking status nor binge drinking modified the relationship between ACEs count (or type) and CDS. In conclusion, the presence of ACEs among women in Hawaii was indicative of CDS in adulthood, notably verbal abuse. Further, a dose response existed between the number of ACEs and the odds for CDS. The concomitant exposure to ACEs and current smoking status or binge drinking did not elevate odds for CDS.

Sandwiched ZnO@Au@CdS nanorod arrays with enhanced visible-light-driven photocatalytical performance

NASA Astrophysics Data System (ADS)

Ren, Shoutian; Wang, Yingying; Fan, Guanghua; Gao, Renxi; Liu, Wenjun

2017-11-01

The development of high-performance photocatalysts is central to efforts focused on taking advantage of solar energy to overcome environmental and energy crises. Integrating different functional materials artfully into nanostructures can deliver more efficient photocatalytic activity. Here, sandwiched ZnO@Au@CdS nanorod films were synthesized via successive ZnO nanorod electrodeposition, Au sputtering and CdS electrodeposition. The as-synthesized composites were characterized by UV-vis spectrophotometer, x-ray diffractometer, scanning and transmission electron microscopy. Their photocatalytic activity was assessed by degrading Rhodamine B solution under visible light irradiation. ZnO@Au@CdS exhibited better photocatalytic performance than ZnO@CdS throughout the visible light region, and the corresponding enhancement factor of Au nanoparticles was measured as a function of CdS loading amount, and it could reach 190% with CdS deposition for 1 min. The normalized rate constant could reach 0.387 h-1 for ZnO@Au@CdS-1min, which was equivalent to or better than results in reference photocatalysts. The enhancement mechanism of Au nanoparticles was estimated by comparing the monochromatic photocatalytic action spectra with the absorption spectrum of ZnO@Au@CdS, and it was mainly determined by incident photon energy. With selective excitation of Au nanoparticles by incident photons, the excited hot electrons in Au NPs are transferred to the conduction band of ZnO to boost photocatalytic reaction. With selective excitation of CdS, the enhanced interband absorption of CdS and relay station effect of Au nanoparticles should be responsible for the enhanced photocatalytic performance. Our work not only opens the door to the design of efficient supported photocatalysts, but also helps to understand the enhancement mechanism of LSPR effect on the photoelectric conversion of semiconductors.

Green synthesis of multifunctional carbon dots from coriander leaves and their potential application as antioxidants, sensors and bioimaging agents.

PubMed

Sachdev, Abhay; Gopinath, P

2015-06-21

In the present study, a facile one-step hydrothermal treatment of coriander leaves for preparing carbon dots (CDs) has been reported. Optical and structural properties of the CDs have been extensively studied by UV-visible and fluorescence spectroscopic, microscopic (transmission electron microscopy, scanning electron microscopy) and X-ray diffraction techniques. Surface functionality and composition of the CDs have been illustrated by elemental analysis and Fourier transform infrared spectroscopy (FTIR). Quenching of the fluorescence of the CDs in the presence of metal ions is of prime significance, hence CDs have been used as a fluorescence probe for sensitive and selective detection of Fe(3+) ions. Eventually, biocompatibility and bioimaging aspects of CDs have been evaluated on lung normal (L-132) and cancer (A549) cell lines. Qualitative analysis of cellular uptake of CDs has been pursued through fluorescence microscopy, while quantitative analysis using a flow cytometer provided an insight into the concentration and cell-type dependent uptake of CDs. The article further investigates the antioxidant activity of CDs. Therefore, we have validated the practicality of CDs obtained from a herbal carbon source for versatile applications.

Preparation of highly luminescent and biocompatible carbon dots using a new extraction method

NASA Astrophysics Data System (ADS)

Zhang, Rui; Liu, Ying-Bo; Sun, Shu-Qing

2013-10-01

C dots (CDs) are among the most promising emerging fluorescent labels for biological imaging and sensing. A facile new synthesis method was developed using common organic solvents for fabricating CDs from candle soot. The common organic solvents were used as extractants and the obtained CDs have a narrow size distribution with average diameters of about 3.4 nm for ethylene glycol, 3.5 nm for ethanol, and 3.4 nm for n-butanol. This approach is simpler, easier, and more effective than other methods currently used for CD fabrication. The obtained CDs had a high quantum yield (38 %), tunable emission and are water-soluble. The mechanism for the luminescence of the CDs was investigated and the results indicate that the ability of the solvent to disperse the CDs plays a very important role in the photoluminescence of these CDs. The type of organic solvent and the surface groups on the CDs also influenced the optical properties of the CDs. Different emissive traps are shown to play the major role in the luminescence of the carbon materials. An in vitro hemolysis assay was performed and showed that the CDs are biocompatible.

Preoperative planning of calcium deposit removal in calcifying tendinitis of the rotator cuff - possible contribution of computed tomography, ultrasound and conventional X-Ray.

PubMed

Izadpanah, Kaywan; Jaeger, Martin; Maier, Dirk; Südkamp, Norbert P; Ogon, Peter

2014-11-20

The purpose of the present study was to investigate the accuracy of Ultrasound (US), conventional X-Ray (CX) and Computed Tomography (CT) to estimate the total count, localization, morphology and consistency of Calcium deposits (CDs) in the rotator cuff. US, CX and CT imaging was performed pre-operatively in 151 patients who underwent arthroscopic removal of CDs in the rotator cuff. In all procedures: (1) total CD counts were determined, (2) the CDs appearance in each image modality was correlated to the intraoperative consistency and (3) CDs were localized in their relation to the acromion using US, CX and CT. Using US158 CDs, using CT 188 CDs and using CX 164 CDs were identified. Reliable localization of the CDs was possible with all used diagnostic modalities. CT revealed 49% of the CDs to be septated, out of which 85% were uni- and 15% multiseptated. CX was not suitable for prediction of CDs consistency. US reliably predicted viscous-solid CDs consistency only when presenting with full sound extinction (PPV 84.6%) . CT had high positive and negative predictive values for detection of liquid-soft (PPV 92.9%) and viscous-solid (PPV 87.8%) CDs. US and CX are sufficient for preoperative planning of CD removal with regards to localization and prediction of consistency if the deposits present with full sound extinction. This is the case in the majority of the patients. However, in patients with missing sound extinction CT can be recommended if CDs consistency of the deposits should be determined. Satellite deposits or septations are regularly present, which is of importance if complete CD removal is aspired.

Highly fluorescent Zn-doped carbon dots as Fenton reaction-based bio-sensors: an integrative experimental-theoretical consideration.

PubMed

Xu, Quan; Liu, Yao; Su, Rigu; Cai, Lulu; Li, Bofan; Zhang, Yingyuan; Zhang, Linzhou; Wang, Yajun; Wang, Yan; Li, Neng; Gong, Xiao; Gu, Zhipeng; Chen, Yusheng; Tan, Yanglan; Dong, Chenbo; Sreeprasad, Theruvakkattil Sreenivasan

2016-10-20

Heteroatom doped carbon dots (CDs), with high photoluminescence quantum yield (PLQY), are of keen interest in various applications such as chemical sensors, bio-imaging, electronics, and photovoltaics. Zinc, an important element assisting the electron-transfer process and an essential trace element for cells, is a promising metal dopant for CDs, which could potentially lead to multifunctional CDs. In this contribution, we report a single-step, high efficiency, hydrothermal method to synthesize Zn-doped carbon dots (Zn-CDs) with a superior PLQY. The PLQY and luminescence characteristic of Zn-CDs can be tuned by controlling the precursor ratio, and the surface oxidation in the CDs. Though a few studies have reported metal doped CDs with good PLQY, the as prepared Zn-Cds in the present method exhibited a PLQY up to 32.3%. To the best of our knowledge, there is no report regarding the facile preparation of single metal-doped CDs with a QY more than 30%. Another unique attribute of the Zn-CDs is the high monodispersity and the resultant highly robust excitation-independent luminescence that is stable over a broad range of pH values. Spectroscopic investigations indicated that the superior PLQY and luminescence of Zn-CDs are due to the heteroatom directed, oxidized carbon-based surface passivation. Furthermore, we developed a novel and sensitive biosensor for the detection of hydrogen peroxide and glucose leveraging the robust fluorescence properties of Zn-CDs. Under optimal conditions, Zn-CDs demonstrated high sensitivity and response to hydrogen peroxide and glucose over a wide range of concentrations, with a linear range of 10-80 μM and 5-100 μM, respectively, indicating their great potential as a fluorescent probe for chemical sensing.

Influence of wide band gap oxide substrates on the photoelectrochemical properties and structural disorder of CdS nanoparticles grown by the successive ionic layer adsorption and reaction (SILAR) method

PubMed Central

Malashchonak, Mikalai V; Korolik, Olga V; Streltsov, Еugene А; Kulak, Anatoly I

2015-01-01

Summary The photoelectrochemical properties of nanoheterostructures based on the wide band gap oxide substrates (ZnO, TiO2, In2O3) and CdS nanoparticles deposited by the successive ionic layer adsorption and reaction (SILAR) method have been studied as a function of the CdS deposition cycle number (N). The incident photon-to-current conversion efficiency (IPCE) passes through a maximum with the increase of N, which is ascribed to the competition between the increase in optical absorption and photocarrier recombination. The maximal IPCE values for the In2O3/CdS and ZnO/CdS heterostructures are attained at N ≈ 20, whereas for TiO2/CdS, the appropriate N value is an order of magnitude higher. The photocurrent and Raman spectroscopy studies of CdS nanoparticles revealed the occurrence of the quantum confinement effect, demonstrating the most rapid weakening with the increase of N in ZnO/CdS heterostructures. The structural disorder of CdS nanoparticles was characterized by the Urbach energy (E U), spectral width of the CdS longitudinal optical (LO) phonon band and the relative intensity of the surface optical (SO) phonon band in the Raman spectra. Maximal values of E U (100–120 meV) correspond to СdS nanoparticles on a In2O3 surface, correlating with the fact that the CdS LO band spectral width and intensity ratio for the CdS SO and LO bands are maximal for In2O3/CdS films. A notable variation in the degree of disorder of CdS nanoparticles is observed only in the initial stages of CdS growth (several tens of deposition cycles), indicating the preservation of the nanocrystalline state of CdS over a wide range of SILAR cycles. PMID:26734517

Influence of wide band gap oxide substrates on the photoelectrochemical properties and structural disorder of CdS nanoparticles grown by the successive ionic layer adsorption and reaction (SILAR) method.

PubMed

Malashchonak, Mikalai V; Mazanik, Alexander V; Korolik, Olga V; Streltsov, Еugene А; Kulak, Anatoly I

2015-01-01

The photoelectrochemical properties of nanoheterostructures based on the wide band gap oxide substrates (ZnO, TiO2, In2O3) and CdS nanoparticles deposited by the successive ionic layer adsorption and reaction (SILAR) method have been studied as a function of the CdS deposition cycle number (N). The incident photon-to-current conversion efficiency (IPCE) passes through a maximum with the increase of N, which is ascribed to the competition between the increase in optical absorption and photocarrier recombination. The maximal IPCE values for the In2O3/CdS and ZnO/CdS heterostructures are attained at N ≈ 20, whereas for TiO2/CdS, the appropriate N value is an order of magnitude higher. The photocurrent and Raman spectroscopy studies of CdS nanoparticles revealed the occurrence of the quantum confinement effect, demonstrating the most rapid weakening with the increase of N in ZnO/CdS heterostructures. The structural disorder of CdS nanoparticles was characterized by the Urbach energy (E U), spectral width of the CdS longitudinal optical (LO) phonon band and the relative intensity of the surface optical (SO) phonon band in the Raman spectra. Maximal values of E U (100-120 meV) correspond to СdS nanoparticles on a In2O3 surface, correlating with the fact that the CdS LO band spectral width and intensity ratio for the CdS SO and LO bands are maximal for In2O3/CdS films. A notable variation in the degree of disorder of CdS nanoparticles is observed only in the initial stages of CdS growth (several tens of deposition cycles), indicating the preservation of the nanocrystalline state of CdS over a wide range of SILAR cycles.

TiO2 activity enhancement through synergistic effect of photons localization of photonic crystals and the sensitization of CdS quantum dots

NASA Astrophysics Data System (ADS)

Li, Ping; Wang, Yuan; Wang, Ai-Jun; Chen, Sheng-Li

2017-02-01

In this work, the enhancement of TiO2 photocatalytic activity was studied through synergistic effect of the photons localization of photonic crystals and the sensitization of CdS quantum dots (CdS QDs). CdS QDs sensitized TiO2 membrane (denoted as CdS QDs/TiO2) was synthesized through doping the TiO2 membrane with CdS QDs by chemical bath deposition method (CBD). After TiO2 was sensitized with CdS QDs, the edge of light absorption of TiO2 was red-shifted to 470 nm and the light absorption in the range of 400 600 nm was higher than that of plain TiO2 membrane. Another type of composite membrane, CdS QDs/TiO2/SiO2 opal composite membrane was prepared by coupling SiO2 opal (a kind of photonic crystal) layer onto the CdS QDs/TiO2 membrane, and the photonic band gap of the SiO2 opal photonic crystal layer was deliberately planned at the electronic band gap of the CdS QDs. The photodegradation of gaseous CH3CHO (acetaldehyde) was used as probe reaction to test the photocatalytic activity of the as-prepared membranes, and the results showed that the CdS QDs sensitization can significantly improve the photocatalytic activity of TiO2 membrane under visible light irradiation, with the acetaldehyde degradation rate constant (k) on CdS QDs/TiO2 membranes being 1.59 times of that on plain TiO2 membranes. The acetaldehyde degradation rate constant on CdS QDs/TiO2/SiO2 opal composite membrane reached 4 times of that on plain TiO2 membrane. The photocatalytic activity of TiO2 membrane can be improved through synergistic effect of the photons localization of photonic crystals and the sensitization of CdS QDs.

Assessment of Holocene soil erosion rates on the loess plateau in East Poland using sedimentary archives from closed depressions

NASA Astrophysics Data System (ADS)

Kołodyńska-Gawrysiak, Renata; Poesen, Jean; Gawrysiak, Leszek

2016-04-01

Closed depressions (CDs) are typical geomorphological features of the European loess belt. They are closed sedimentation basins that enable the estimation of long-term soil erosion rates for different land use environments. This study was conducted in eastern Poland (Nałęczów Plateau). In this region CDs are rather small landforms and the area of 70% of all CDs does not exceed 1500 m2. The study objective was to assess Holocene soil erosion rates in the loess plateau based on a quantitative analysis of colluvial sediments deposited in CDs. Two representative CDs were selected for this study: one CD is located in an old (long-term) forest and the other is situated in a long-term agricultural land. The maximum depth of the CD in the forest, the mean slope gradient and area of the corresponding catchment are 4.9 m, 3.410 and 7568 m² respectively. For the CD in agricultural land these values are 3.2 m, 2.760 and 5156 m² respectively. In both CDs several dozen of drillings and two trenches (2 m long, 1m wide, 2 m deep) were made in the deepest point of the CDs. Mean long-term soil erosion rates were calculated based on the stratigraphy of the soil-sediment sequence infilling the CDs. C-14 and OSL datings of soils and colluvial sediments within the CDs were obtained. For the long-term agricultural used catchment of the CD it was calculated that since 6.31 ± 0.35 ka BP the mean annual soil loss due to water and tillage erosion is 0.63-0.7 t/ha/year or 279.3 mm. In the prehistoric period since 6.31 ± 0.35 ka BP until 1026-1162 AD the mean annual soil erosion rate amounted to 0,10-0.11 t/ha/year or 41.5 mm. During the last ca. 1000 years mean soil erosion rates increased to 3.99-4.63 t/ha/year or 249.2 mm. Results of long-term soil erosion rates (calculated using colluvial sediment sequences in CDs) from agricultural catchments in the loess regions of eastern Poland (this study) and Central Belgium (Gillijns et al. 2005) are quite similar. For the forested catchment of the CD the mean annual soil erosion rate since at least ca. 1000 years is 0.073-0.086 t/ha/year or 41.9 mm. In this catchment soil erosion and correlative colluviation deposits occurred mainly in prehistoric times. CDs play an important role for archiving sediments which allow to reconstruct both natural and anthropogenic processes in the past. The study of these sediment archives allows a better understanding of human-environment interactions and its impact on long-term soil erosion rates. Acknowledgements: The research project was financially supported by the National Centre of Science - project PB-B-12-287-00-13: The origin and evolution of closed depressions in the loess area of the Lublin Upland and their importance for the reconstruction of postglacial morphogenesis of the loess covers. References: Gillijns K., Poesen J., Deckers J., 2005: On the characteristics and origin of closed depression in loess-derived soils in Europe- a case study from central Belgium. Catena 60, 43-58.

Structural and optoelectronic studies on Ag-CdS quantum dots

NASA Astrophysics Data System (ADS)

Ibrahim Mohammed S., M.; Gubari, Ghamdan M. M.; Huse, Nanasaheb P.; Dive, Avinash S.; Sharma, Ramphal

2018-05-01

In the present study, we have successfully deposited CdS quantum dot thin films and Ag doped CdS on a glass slide by simple and economical chemical bath deposition at room temperature. The X-ray diffraction method analysis reveals that CdS thin films exhibit hexagonal structure when compared with standard JCPDS data. The estimated average crystallite size of the quantum dots and resulted in the least crystallite size of ˜9 nm. a comparison between the optical and electrical properties of the films before and after doping Ag was made through measuring and analyzing the curves for UV and I-V. From UV absorption spectra we observed that the samples exhibited a band edge near ˜400 nm with a slight deviation with the presence of excitonic peak for both CdS and Ag doped CdS. The presence of excitonic peak may be referred to the formation of quantum dots. The calculated band gap energy of thin films was found to be 3.45 eV and 3.15 eV for both CdS and Ag doped CdS thin films respectively, where the optical absorption spectra of Ag doped CdS nanoparticles also exhibit shift with respect to that of CdS quantum dots thin films. The photosensitive of CdS thin films show an increase in photocurrent when Ag doped CdS.

Hexagonal pencil-like CdS nanorods: Facile synthesis and enhanced visible light photocatalytic performance

NASA Astrophysics Data System (ADS)

An, Liang; Wang, Guanghui; Zhao, Lei; Zhou, Yong; Gao, Fang; Cheng, Yang

2015-07-01

In the present study, hexagonal pencil-like CdS nanorods have been successfully synthesized through a typical facile and economical one-step hydrothermal method without using any surfactant or template. The product was characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and energy dispersive analysis of X-ray (EDX). The results revealed that the prepared CdS photocatalyst consisted of a large quantity of straight and smooth solid hexagonal nanorods and a few nanoparticles. The photocatalytic activities of CdS nanorods and commercial CdS powders were investigated by the photodegradation of Orange II (OII) in aqueous solution under visible light, and the CdS nanorods presented the highest photocatalytic activity. Its photocatalytic efficiency enhancement was attributed to the improved transmission of photogenerated electron-hole pairs in the CdS nanostructures. The present findings may provide a facile approach to synthesize high efficient CdS photocatalysts.

Highly selective and sensitive detection of Cu2+ with lysine enhancing bovine serum albumin modified-carbon dots fluorescent probe.

PubMed

Liu, Jia-Ming; Lin, Li-ping; Wang, Xin-Xing; Lin, Shao-Qin; Cai, Wen-Lian; Zhang, Li-Hong; Zheng, Zhi-Yong

2012-06-07

Based on the ability of lysine (Lys) to enhance the fluorescence intensity of bovine serum albumin modified-carbon dots (CDs-BSA) to decrease surface defects and quench fluorescence of the CDs-BSA-Lys system in the presence of Cu(2+) under conditions of phosphate buffer (PBS, pH = 5.0) at 45 °C for 10 min, a sensitive Lys enhancing CDs-BSA fluorescent probe was designed. The environment-friendly, simple, rapid, selective and sensitive fluorescent probe has been utilized to detect Cu(2+) in hair and tap water samples and it achieved consistent results with those obtained by inductively coupled plasma mass spectroscopy (ICP-MS). The mechanism of the proposed assay for the detection of Cu(2+) is discussed.

Effect of CdS nanocrystals on charge transport mechanism in poly(3-hexylthiophene)

NASA Astrophysics Data System (ADS)

Khan, Mohd Taukeer; Almohammedi, Abdullah

2017-08-01

The present manuscript demonstrates the optical and electrical characteristics of poly(3-hexylthiophene) (P3HT) and cadmium sulphide (CdS) hybrid nanocomposites. Optical results suggest that there is a formation of charge transfer complex (CTC) between host P3HT and guest CdS nanocrystals (NCs). Electrical properties of P3HT and P3HT-CdS thin films have been studied in hole only device configurations at different temperatures (290 K-150 K), and results were analysed by the space charge limited conduction mechanism. Density of traps and characteristic trap energy increase on incorporation of inorganic NCs in the polymer matrix, which might be due to the additional favourable energy states created by CdS NCs in the band gap of P3HT. These additional trap states assist charge carriers to move quicker which results in enhancement of hole mobility from 7 × 10-6 to 5.5 × 10-5 cm2/V s in nanocomposites. These results suggest that the P3HT-CdS hybrid system has desirable optical and electrical properties for its applications to photovoltaics devices.

Managing tile drainage, subirrigation, and nitrogen fertilization to enhance crop yields and reduce nitrate loss.

PubMed

Drury, C F; Tan, C S; Reynolds, W D; Welacky, T W; Oloya, T O; Gaynor, J D

2009-01-01

Improving field-crop use of fertilizer nitrogen is essential for protecting water quality and increasing crop yields. The objective of this study was to determine the effectiveness of controlled tile drainage (CD) and controlled tile drainage with subsurface irrigation (CDS) for mitigating off-field nitrate losses and enhancing crop yields. The CD and CDS systems were compared on a clay loam soil to traditional unrestricted tile drainage (UTD) under a corn (Zea Mays L.)-soybean (Glycine Max. (L.) Merr.) rotation at two nitrogen (N) fertilization rates (N1: 150 kg N ha(-1) applied to corn, no N applied to soybean; N2: 200 kg N ha(-1) applied to corn, 50 kg N ha(-1) applied to soybean). The N concentrations in tile flow events with the UTD treatment exceeded the provisional long-term aquatic life limit (LT-ALL) for freshwater (4.7 mg N L(-1)) 72% of the time at the N1 rate and 78% at the N2 rate, whereas only 24% of tile flow events at N1 and 40% at N2 exceeded the LT-ALL for the CDS treatment. Exceedances in N concentration for surface runoff and tile drainage were greater during the growing season than the non-growing season. At the N1 rate, CD and CDS reduced average annual N losses via tile drainage by 44 and 66%, respectively, relative to UTD. At the N2 rate, the average annual decreases in N loss were 31 and 68%, respectively. Crop yields from CDS were increased by an average of 2.8% relative to UTD at the N2 rate but were reduced by an average of 6.5% at the N1 rate. Hence, CD and CDS were effective for reducing average nitrate losses in tile drainage, but CDS increased average crop yields only when additional N fertilizer was applied.

Ultrasound-assisted microwave preparation of Ag-doped CdS nanoparticles.

PubMed

Ma, Jun; Tai, Guo'an; Guo, Wanlin

2010-03-01

Ag-doped CdS nanoparticles were synthesized by an ultrasound-assisted microwave synthesis method. The X-ray diffraction patterns reveal a structural evolution from cubic to hexagonal with increasing molar ratios of Ag(+)/Cd(2+) from 0% to 5%. It shows that the Ag-doped hexagonal CdS nanoparticles are polycrystal. The X-ray photoelectron spectroscopy of the CdS nanoparticles doping with 5% Ag(+) shows that the doped Ag in CdS is metallic. Simultaneously, the characteristic Raman peaks of the CdS nanoparticles enhance with increasing Ag(+) concentrations. The photocatalytic activity of different Ag-doped samples show a reasonable change due to different ratios of Ag which doped into CdS. Copyright 2009 Elsevier B.V. All rights reserved.

Nitrogen and sulfur co-doped carbon dots with strong blue luminescence.

PubMed

Ding, Hui; Wei, Ji-Shi; Xiong, Huan-Ming

2014-11-21

Sulfur-doped carbon dots (S-CDs) with a quantum yield (QY) of 5.5% and nitrogen, sulfur co-doped carbon dots (N,S-CDs) with a QY of 54.4% were synthesized, respectively, via the same hydrothermal route using α-lipoic acid as the carbon source. The obtained S-CDs and N,S-CDs had similar sizes but different optical features. The QY of N,S-CDs was gradually enhanced when extending the reaction time to increase the nitrogen content. After careful characterization of these CDs, the doped nitrogen element was believed to be in the form of C=N and C-N bonds which enhanced the fluorescence efficiency significantly. Meanwhile, the co-doped sulfur element was found to be synergistic for nitrogen doping in N,S-CDs. The optimal N,S-CDs were successfully employed as good multicolor cell imaging probes due to their fine dispersion in water, excitation-dependent emission, excellent fluorescence stability and low toxicity. Besides, such N,S-CDs showed a wide detection range and excellent accuracy as fluorescent sensors for Fe(3+) ions.

Chemical Synthesis and Optical Properties of CdS Poly(Lactic Acid) Nanocomposites and Their Transparent Fluorescent Films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Cai-Feng; Cheng, Yu-Peng; Xie, He-Yi

2011-01-01

This paper describes the chemical synthesis of cadmium sulfide (CdS) polymer nanocomposites by covalently grafting poly(lactic acid) (PLA) onto the surfaces of CdS nanocrystals (NCs). Synthesis of the nanocomposites involved two steps. Lactic acid (LA) capped CdS NCs were first prepared by reacting cadmium chloride (CdCl2) with sodium sulfide (Na2S) using LA as the organic ligand in H2O/N,N-dimethylformamide (DMF) solution. Next CdS PLA nanocomposites were formed by in situ ring-opening polymerization of lactide on the surface of modified CdS NCs. Transparent fluorescent films were then successfully prepared by blending as-prepared CdS PLA nanocomposites with high-molecular-weight PLA. The as-prepared CdS NCsmore » and their nanocomposites were studied by transmission electron microscopic imaging, thermogravimetric analyses, and spectroscopic measurements (ultraviolet-visible absorption and photoluminescence). The spectroscopic studies revealed that the CdS polymer nanocomposites exhibited good optical properties in terms of their photoluminescence and transparency.« less

Carbon dots based immunosorbent assay for the determination of GFAP in human serum

NASA Astrophysics Data System (ADS)

Ma, Yunsu; Xu, Guanhong; Wei, Fangdi; Cen, Yao; Song, Yueyue; Ma, Yujie; Xu, Xiaoman; Shi, Menglan; Sohail, Muhammad; Hu, Qin

2018-04-01

Glial fibrillary acidic protein (GFAP) is expressed in the central nervous system and the level of GFAP normally rises with brain injury and astroglial tumors. So, serum GFAP is used as a marker for diagnosing various types of brain damage and astroglial tumors. In this study, a new sensor based on carbon dots (CDs) linked with antibodies to specifically detect GFAP in human serum was developed. Anti-GFAP (Ab1) linked with protein A/G agarose resin (PA/G) as a capture antibody (PA/G-Ab1) and anti-GFAP (Ab2) labeled with CDs as a detection antibody (CDs-Ab2) were prepared firstly. Then the CD-linked antibody immunosorbent assay (CLAISA) method was constructed based on the sandwich conjunction reaction among PA/G-Ab1, GFAP, and CDs-Ab2. CLAISA, using the fluorescence of PA/G-Ab1-GFAP-Ab2-CDs as the direct signal, enabled the proposed immunosensor to detect GFAP sensitively with a linear range of 0.10-8.00 ng ml-1 and a detection limit of 25 pg ml-1. This method was applied to the determination of GFAP in human serum by the standard addition method, and the results showed high accuracy and precision. Considering the easy synthetic process and excellent performance of CLAISA, this method has great potential to be used to monitor GFAP in the clinic.

Ag nanoclusters could efficiently quench the photoresponse of CdS quantum dots for novel energy transfer-based photoelectrochemical bioanalysis.

PubMed

Zhang, Ling; Sun, Yue; Liang, Yan-Yu; He, Jian-Ping; Zhao, Wei-Wei; Xu, Jing-Juan; Chen, Hong-Yuan

2016-11-15

Herein the influence of ultrasmall Ag nanoclusters (Ag NCs) against CdS quantum dots (QDs) in a photoelectrochemical (PEC) nanosystem was exploited for the first time, based on which a novel PEC bioanalysis was successfully developed via the efficient quenching effect of Ag NCs against the CdS QDs. In a model system, DNA assay was achieved by using molecular beacon (MB) probes anchored on a CdS QDs modified electrode, and the MB probes contain two segments that can hybridize with both target DNA sequence and the label of DNA encapsulated Ag NCs. After the MB probe was unfolded by the target DNA sequence, the labels of oligonucleotide encapsulated Ag NCs would be brought in close proximity to the CdS QDs electrode surface, and efficient photocurrent quenching of QDs could be resulted from an energy transfer process that originated from NCs. Thus, by monitoring the attenuation in the photocurrent signal, an elegant and sensitive PEC DNA bioanalysis could be accomplished. The developed biosensor displayed a linear range from 1.0pM to 10nM and the detection limit was experimentally found to be of 0.3pM. This work presents a feasible signaling principle that could act as a common basis for general PEC bioanalysis development. Copyright © 2016 Elsevier B.V. All rights reserved.

Preparation and characterization of photocatalytic carbon dots-sensitized electrospun titania nanostructured fibers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Haopeng; Zhu, Yihua, E-mail: yhzhu@ecust.edu.cn; Cao, Huimin

2013-02-15

Graphical abstract: Display Omitted Highlights: ► The TiO{sub 2}-CDs nanostructured fibers are fabricated by using APS combining the electrospinning TiO{sub 2} nanostructured fibers and CDs. ► The CD can work as a photosensitizer in the degradation of rhodamine B under visible light irradiation. ► The TiO{sub 2}-CDs nanostructured fibers exhibit enhanced photocatalytic efficiency and can be easily handled and recycled. -- Abstract: The carbon dots (CDs) are new functional carbon-aceous materials. Compared to conventional dye molecules and semiconductor quantum dots, CDs are superior in chemical inertness and low toxicity. The TiO{sub 2}-CDs nanostructured fibers were fabricated by combining the electrospinningmore » technique and reflux method. Compared with the pure TiO{sub 2} nanostructured fibers and P25, the TiO{sub 2}-CDs nanostructured fibers exhibited enhanced photocatalytic efficiency of photodegradation of rhodamine B (RhB) under visible light irradiation. The enhanced photocatalytic activity of TiO{sub 2}-CDs nanostructured fibers could be attributed to the presence of CDs embedded in TiO{sub 2} nanostructured fibers. The CD can work as a photosensitizer in the degradation. Furthermore, the TiO{sub 2}-CDs nanostructured fibers could be easily handled and recycled due to their one-dimensional nanostructural property.« less

National automotive sampling system crashworthiness data system 1994-1996

DOT National Transportation Integrated Search

1999-10-01

This report focuses attention on occupants of those passenger vehicles that were towed from : the crash scene. NHTSA's National Automotive Sampling System (NASS)/ Crashworthiness : Data System (CDS) collects detailed information on towed passenger ve...

Active CdS/rGO photocatalyst by a high temperature gas-solid reaction for hydrogen production by splitting of water

NASA Astrophysics Data System (ADS)

Singh, Arvind; Sinha, A. S. K.

2018-02-01

rGO supported CdS photocatalysts has been prepared by a two steps method, i.e. impregnation of GO/rGO with CdSO4 followed by a high temperature reaction with H2S gas. Activity of this catalyst was superior to a catalyst of same composition prepared by commonly reported hydrothermal technique. Detailed microstructure studies were carried out using FTIR, PL, DRS, XRD, TEM, SAED, TPO and XPS. A much greater chemical interaction at the interface of CdS and rGO and also a higher absorption of visible light were observed in the reported catalyst. It has been concluded that the high temperature reaction with H2S has imparted n-type semiconductivity to CdS which with p-type rGO and synergy of chemical interaction at the interface has resulted into formation of a p-n hetrojunction. The formation of hetrojunction and high electron mobility of rGO has given a superior activity due to an efficient charge separation to the catalyst prepared by the technique reported in this paper.

Green synthesis of carbon dots originated from Lycii Fructus for effective fluorescent sensing of ferric ion and multicolor cell imaging.

PubMed

Sun, Xiaohan; He, Jiang; Yang, Shenghong; Zheng, Mingda; Wang, Yingying; Ma, Shuang; Zheng, Haipeng

2017-10-01

Green, economical and effective method was developed for synthesis of fluorescent carbon dots (CDs), using one-pot hydrothermal treatment of Lycii Fructus. Optical and structural properties of the CDs have been extensively studied by UV-visible and fluorescence spectroscopic, x-ray diffraction (XRD) techniques, transmission electron microscopy (TEM) and high resolution TEM (HRTEM). Surface functionality and composition of CDs has been illustrated by Fourier transform infrared spectroscopy (FTIR), x-ray photoelectron spectroscopy (XPS) spectra and elemental analysis. The fabricated CDs possess stable fluorescent properties. The fluorescent quantum yield of the CDs can reach 17.2%. The prepared CDs emitted a broad fluorescence between 415 and 545nm and their fluorescence was tuned by changing excitation wavelength. Meanwhile, the fluorescence intensity of the CDs could be significantly quenched by Fe 3+ (turn-off). The CDs exhibit captivating sensitivity and selectivity toward Fe 3+ with a linear range from 0 to 30μM and a detection limit of 21nM. The prepared CDs were successfully applied to the determination of Fe 3+ in the urine samples, the water samples from the from the Yellow River and living HeLa (Henrietta Lacks) cells. Moreover, the low-toxicity and excellent biocompatibility of the CDs were evaluated through MTT assay on HeLa cells. The CDs were also employed as fluorescent probes for multicolor imaging of HeLa cells successfully. Copyright © 2017 Elsevier B.V. All rights reserved.

CIC-DUX4 Induces Small Round Cell Sarcomas Distinct from Ewing Sarcoma.

PubMed

Yoshimoto, Toyoki; Tanaka, Miwa; Homme, Mizuki; Yamazaki, Yukari; Takazawa, Yutaka; Antonescu, Cristina R; Nakamura, Takuro

2017-06-01

CIC-DUX4 sarcoma (CDS) or CIC-rearranged sarcoma is a subcategory of small round cell sarcoma resembling the morphological phenotypes of Ewing sarcoma (ES). However, recent clinicopathologic and molecular genetic analyses indicate that CDS is an independent disease entity from ES. Few ancillary markers have been used in the differential diagnosis of CDS, and additional CDS-specific biomarkers are needed for more definitive classification. Here, we report the generation of an ex vivo mouse model for CDS by transducing embryonic mesenchymal cells (eMC) with human CIC-DUX4 cDNA. Recipient mice transplanted with eMC-expressing CIC-DUX4 rapidly developed an aggressive, undifferentiated sarcoma composed of small round to short spindle cells. Gene-expression profiles of CDS and eMC revealed upregulation of CIC-DUX4 downstream genes such as PEA3 family genes, Ccnd2, Crh , and Zic1 IHC analyses for both mouse and human tumors showed that CCND2 and MUC5AC are reliable biomarkers to distinguish CDS from ES. Gene silencing of CIC-DUX4 as well as Ccnd2, Ret , and Bcl2 effectively inhibited CDS tumor growth in vitro The CDK4/6 inhibitor palbociclib and the soft tissue sarcoma drug trabectedin also blocked the growth of mouse CDS. In summary, our mouse model provides important biological information about CDS and provides a useful platform to explore biomarkers and therapeutic agents for CDS. Cancer Res; 77(11); 2927-37. ©2017 AACR . ©2017 American Association for Cancer Research.

Optical Properties of CdS Nanobelts and Nanosaws Synthesized by Thermal Evaporation Method

NASA Astrophysics Data System (ADS)

Peng, Zhi-wei; Zou, Bing-suo

2012-04-01

By a simple one-step H2-assisted thermal evaporation method, high quality CdS nanostructures have been successfully fabricated on Au coated Si substrates in large scale. The as-synthesized CdS nanostructures consisted of sword-like nanobelts and toothed nanosaws with a single-crystal hexagonal wurtzite structure. The deposition temperature played an important role in determining the size and morphology of the CdS nanostructures. A combination of vapor-liquid-solid and vapor-solid growth mechanisms were proposed to interpret the formation of CdS nanostructures. Photoluminescence measurement indicated that the nanobelts and nanosaws have a prominent green emission at about 512 nm, which is the band-to-band emission of CdS. The waveguide characteristics of both types of CdS nanostructures were observed and discussed.

Intestinal Permeability of β-Lapachone and Its Cyclodextrin Complexes and Physical Mixtures.

PubMed

Mangas-Sanjuan, Victor; Gutiérrez-Nieto, Jorge; Echezarreta-López, Magdalena; González-Álvarez, Isabel; González-Álvarez, Marta; Casabó, Vicente-Germán; Bermejo, Marival; Landin, Mariana

2016-12-01

β-Lapachone (βLAP) is a promising, poorly soluble, antitumoral drug. βLAP combination with cyclodextrins (CDs) improves its solubility and dissolution but there is not enough information about the impact of cyclodextrins on βLAP intestinal permeability. The objectives of this work were to characterize βLAP intestinal permeability and to elucidate cyclodextrins effect on the dissolution properties and on the intestinal permeability. The final goal was to evaluate CDs influence on the oral absorption of βLAP. Binary systems (physical mixtures and inclusion complexes) including βLAP and CDs (β-cyclodextrin: βCD, random-methyl-β-cyclodextrin: RMβCD and sulfobutylether-β-cyclodextrin: SBEβCD) have been prepared and analysed by differential scanning calorimetry. βLAP (and its combinations with CDs) absorption rate coefficients and effective permeability values have been determined in vitro in MDCK or MDCK-Mdr1 monolayers and in situ in rat by a closed loop perfusion technique. DSC results confirmed the formation of the inclusion complexes. βLAP-CDs inclusion complexes improve drug solubility and dissolution rate in comparison with physical mixtures. βLAP presented a high permeability value which can provide complete oral absorption. Its oral absorption is limited by its low solubility and dissolution rate. Cyclodextrin (both as physical mixtures and inclusion complexes) showed a positive effect on the intestinal permeability of βLAP. Complexation with CDs does not reduce βLAP intestinal permeability in spite of the potential negative effect of the reduction in free fraction of the drug. The use of RMβCD or SBEβCD inclusion complexes could benefit βLAP oral absorption by enhancing its solubility, dissolution rate and permeability.

Hospital information systems: experience at the fully digitized Seoul National University Bundang Hospital.

PubMed

Yoo, Sooyoung; Hwang, Hee; Jheon, Sanghoon

2016-08-01

The different levels of health information technology (IT) adoption and its integration into hospital workflow can affect the maximization of the benefits of using of health IT. We aimed at sharing our experiences and the journey to the successful adoption of health IT over 13 years at a tertiary university hospital in South Korea. The integrated system of comprehensive applications for direct care, support care, and smart care has been implemented with the latest IT and a rich user information platform, achieving the fully digitized hospital. The users experience design methodology, barcode and radio-frequency identification (RFID) technologies, smartphone and mobile technologies, and data analytics were integrated into hospital workflow. Applications for user-centered electronic medical record (EMR) and clinical decision support (CDS), closed loop medication administration (CLMA), mobile EMR and dashboard system for care coordination, clinical data warehouse (CDW) system, and patient engagement solutions were designed and developed to improve quality of care, work efficiency, and patient safety. We believe that comprehensive electronic health record systems and patient-centered smart hospital applications will go a long way in ensuring seamless patient care and experience.

Biomolecule-assisted construction of cadmium sulfide hollow spheres with structure-dependent photocatalytic activity.

PubMed

Wei, Chengzhen; Zang, Wenzhe; Yin, Jingzhou; Lu, Qingyi; Chen, Qun; Liu, Rongmei; Gao, Feng

2013-02-25

In this study, we report the synthesis of monodispersive solid and hollow CdS spheres with structure-dependent photocatalytic abilities for dye photodegradation. The monodispersive CdS nanospheres were constructed with the assistance of the soulcarboxymthyi chitosan biopolymer under hydrothermal conditions. The solid CdS spheres were corroded by ammonia to form hollow CdS nanospheres through a dissolution-reprecipitation mechanism. Their visible-light photocatalytic activities were investigated, and the results show that both the solid and the hollow CdS spheres have visible-light photocatalytic abilities for the photodegradation of dyes. The photocatalytic properties of the CdS spheres were demonstrated to be structure dependent. Although the nanoparticles comprising the hollow spheres have larger sizes than those comprising the solid spheres, the hollow CdS spheres have better photocatalytic performances than the solid CdS spheres, which can be attributed to the special hollow structure. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Resonance Rayleigh scattering technique for simple and sensitive analysis of tannic acid with carbon dots

NASA Astrophysics Data System (ADS)

Shi, Ying; Yang, Liu; Zhu, Jinghui; Yang, Jidong; Liu, Shaopu; Qiao, Man; Duan, Ruilin; Hu, Xiaoli

2017-02-01

Carbon dots (CDs) are raising a substantial amount of attention owing to their many unique and novel physicochemical properties. Herein one-pot synthesized CDs, to the best of our knowledge, were first served as the robust nanoprobe for detection tannic acid (TA) based on resonance Rayleigh scattering technique. The as-prepared CDs can combine with TA via hydrogen bond, resulting in remarkable enhancement of scattering signal with no changes in the fluorescence of CDs. Therefore, a novel protocol for TA determination was established and this strategy allowed quantitative detection of TA in the linear range of 0.2-10.0 μmol L- 1 with an excellent detection limit of 9.0 nmol L- 1. Moreover, the CDs based nanoprobe can be applied to the determination of TA in water sample with satisfactory results. Our study can potentially influence our current views on CDs and particularly impressive and offers new insights into application of CDs beyond the traditional understanding of CDs.

Architecture Design of Healthcare Software-as-a-Service Platform for Cloud-Based Clinical Decision Support Service

PubMed Central

Oh, Sungyoung; Cha, Jieun; Ji, Myungkyu; Kang, Hyekyung; Kim, Seok; Heo, Eunyoung; Han, Jong Soo; Kang, Hyunggoo; Chae, Hoseok; Hwang, Hee

2015-01-01

Objectives To design a cloud computing-based Healthcare Software-as-a-Service (SaaS) Platform (HSP) for delivering healthcare information services with low cost, high clinical value, and high usability. Methods We analyzed the architecture requirements of an HSP, including the interface, business services, cloud SaaS, quality attributes, privacy and security, and multi-lingual capacity. For cloud-based SaaS services, we focused on Clinical Decision Service (CDS) content services, basic functional services, and mobile services. Microsoft's Azure cloud computing for Infrastructure-as-a-Service (IaaS) and Platform-as-a-Service (PaaS) was used. Results The functional and software views of an HSP were designed in a layered architecture. External systems can be interfaced with the HSP using SOAP and REST/JSON. The multi-tenancy model of the HSP was designed as a shared database, with a separate schema for each tenant through a single application, although healthcare data can be physically located on a cloud or in a hospital, depending on regulations. The CDS services were categorized into rule-based services for medications, alert registration services, and knowledge services. Conclusions We expect that cloud-based HSPs will allow small and mid-sized hospitals, in addition to large-sized hospitals, to adopt information infrastructures and health information technology with low system operation and maintenance costs. PMID:25995962

Doxorubicin conjugated functionalizable carbon dots for nucleus targeted delivery and enhanced therapeutic efficacy

NASA Astrophysics Data System (ADS)

Yang, Lei; Wang, Zheran; Wang, Ju; Jiang, Weihua; Jiang, Xuewei; Bai, Zhaoshi; He, Yunpeng; Jiang, Jianqi; Wang, Dongkai; Yang, Li

2016-03-01

Carbon dots (CDs) have shown great potential in imaging and drug/gene delivery applications. In this work, CDs functionalized with a nuclear localization signal peptide (NLS-CDs) were employed to transport doxorubicin (DOX) into cancer cells for enhanced antitumor activity. DOX was coupled to NLS-CDs (DOX-CDs) through an acid-labile hydrazone bond, which was cleavable in the weakly acidic intracellular compartments. The cytotoxicity of DOX-CD complexes was evaluated by the MTT assay and the cellular uptake was monitored using flow cytometry and confocal laser scanning microscopy. Cell imaging confirmed that DOX-CDs were mainly located in the nucleus. Furthermore, the complexes could efficiently induce apoptosis in human lung adenocarcinoma A549 cells. The in vivo therapeutic efficacy of DOX-CDs was investigated in an A549 xenograft nude mice model and the complexes exhibited an enhanced ability to inhibit tumor growth compared with free DOX. Thus, the DOX-CD conjugates may be exploited as promising drug delivery vehicles in cancer therapy.Carbon dots (CDs) have shown great potential in imaging and drug/gene delivery applications. In this work, CDs functionalized with a nuclear localization signal peptide (NLS-CDs) were employed to transport doxorubicin (DOX) into cancer cells for enhanced antitumor activity. DOX was coupled to NLS-CDs (DOX-CDs) through an acid-labile hydrazone bond, which was cleavable in the weakly acidic intracellular compartments. The cytotoxicity of DOX-CD complexes was evaluated by the MTT assay and the cellular uptake was monitored using flow cytometry and confocal laser scanning microscopy. Cell imaging confirmed that DOX-CDs were mainly located in the nucleus. Furthermore, the complexes could efficiently induce apoptosis in human lung adenocarcinoma A549 cells. The in vivo therapeutic efficacy of DOX-CDs was investigated in an A549 xenograft nude mice model and the complexes exhibited an enhanced ability to inhibit tumor growth compared with free DOX. Thus, the DOX-CD conjugates may be exploited as promising drug delivery vehicles in cancer therapy. Electronic supplementary information (ESI) available: FT-IR and 1H NMR spectra of DOX-CD complexes. See DOI: 10.1039/c6nr00247a

Visible light CrO4(2-) reduction using the new CuAlO2/CdS hetero-system.

PubMed

Brahimi, R; Bessekhouad, Y; Nasrallah, N; Trari, M

2012-06-15

In this study, 64% of hexavalent chromium Cr(VI) reduction from the initial concentration (10(-4) M) is reported under visible light using the (CuAlO(2)/CdS) hetero-system. In this new hetero-system, low doped CuAlO(2) delafossite, synthesized by sol-gel works as an electrons reservoir with a wide space charge region (440 nm). In this case, the electron transfer to chromate is mediated via the hexagonal CdS variety, whose conduction band level is at -1.08 V with respect to the saturated calomel electrode which is more negative than the CrO(4)(2-)/Cr(3+) level. This high reduction rate is achieved under optimized pH and CuAlO(2) percentage. Moreover, salicylic acid gives the best performance among hole scavengers and CuAlO(2) approaches 100% photostability at pH 7.5. The photo-catalytic process follows a pseudo first order kinetic with a half life of 2h. The reaction products are identified by UV-visible spectrophotometry and linear voltametry at a platinum rotating electrode. The results reveal the presence of Cr(3+) after irradiation. Copyright © 2012. Published by Elsevier B.V.

Impact of Clinical Decision Support on Radiography for Acute Ankle Injuries: A Randomized Trial

PubMed Central

Tajmir, Shahein; Raja, Ali S.; Ip, Ivan K.; Andruchow, James; Silveira, Patricia; Smith, Stacy; Khorasani, Ramin

2017-01-01

Introduction While only 15–20% of patients with foot and ankle injuries presenting to urgent care centers have clinically significant fractures, most undergo radiography. We examined the impact of electronic point-of-care clinical decision support (CDS) on adherence to the Ottawa Ankle Rules (OAR), as well as use and yield of foot and ankle radiographs in patients with acute ankle injury. Methods We obtained institutional review board approval for this randomized controlled study performed April 18, 2012—December 15, 2013. All ordering providers credentialed at an urgent care affiliated with a quaternary care academic hospital were randomized to either receive or not receive CDS, based on the OAR and integrated into the physician order-entry system, with feedback at the time of imaging order. If the patient met OAR low-risk criteria, providers were advised against imaging and could either cancel the order or ignore the alert. We identified patients with foot and ankle complaints via ICD-9 billing codes and electronic health records and radiology reports reviewed for those who were eligible. Chi-square was used to compare adherence to the OAR (primary outcome), radiography utilization rate and radiography yield of foot and ankle imaging (secondary outcomes) between the intervention and control groups. Results Of 14,642 patients seen at urgent care during the study period, 613 (4.2%, representing 632 visits) presented with acute ankle injury and were eligible for application of the OAR; 374 (59.2%) of these were seen by control-group providers. In the intervention group, CDS adherence was higher for both ankle (239/258=92.6% vs. 231/374=61.8%, p=0.02) and foot radiography (209/258=81.0% vs. 238/374=63.6%; p<0.01). However, ankle radiography use was higher in the intervention group (166/258=64.3% vs. 183/374=48.9%; p<0.01), while foot radiography use (141/258=54.6% vs. 202/374=54.0%; p=0.95) was not. Radiography yield was also higher in the intervention group (26/307=8.5% vs. 18/385=4.7%; p=0.04). Conclusion Clinical decision support, previously demonstrated to improve guideline adherence for high-cost imaging, can also improve guideline adherence for radiography – as demonstrated by increased OAR adherence and increased imaging yield. PMID:28435501

Optimal nitrogen and phosphorus codoping carbon dots towards white light-emitting device

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Feng; Wang, Yaling; Miao, Yanqin

Through a one-step fast microwave-assisted approach, nitrogen and phosphorus co-doped carbon dots (N,P-CDs) were synthesized using ammonium citrate (AC) as a carbon source and phosphates as additive reagent. Under the condition of an optimal reaction time of 140 s, the influence of additive with different N and P content on fluorescent performance of N,P-CDs was further explored. It was concluded that high nitrogen content and moderate phosphorus content are necessary for obtaining high quantum yield (QY) N,P-CDs, among which the TAP-CDs (CDs synthesized using ammonium phosphate as additive reagent) show high quantum yield (QY) of 62% and red-green-blue (RGB) spectral compositionmore » of 51.67%. Besides, the TAP-CDs exhibit satisfying thermal stability within 180 °C. By virtue of good optical and thermal properties of TAP-CDs, a white light-emitting device (LED) was fabricated by combining ultraviolet chip with TAP-CDs as phosphor. The white LED emits bright warm-white light with the CIE chromaticity coordinate of (0.38, 0.35) and the corresponding color temperature (CCT) of 4450 K, indicating the potential of TAP-CDs phosphor in white LED.« less

Highly Efficient Carbon Dots with Reversibly Switchable Green-Red Emissions for Trichromatic White Light-Emitting Diodes.

PubMed

Yuan, Biao; Guan, Shanyue; Sun, Xingming; Li, Xiaoming; Zeng, Haibo; Xie, Zheng; Chen, Ping; Zhou, Shuyun

2018-05-09

Carbon dots (CDs) have potentials to be utilized in optoelectronic devices, bioimaging, and photocatalysis. The majority of the current CDs with high quantum yield to date were limited in the blue light emission region. Herein, on the basis of surface electron-state engineering, we report a kind of CDs with reversible switching ability between green and red photoluminescence with a quantum yield (QY) of both up to 80%. Highly efficient green and red solid-state luminescence is realized by doping CDs into a highly transparent matrix of methyltriethoxysilane and 3-triethoxysilylpropylamine to form CDs/gel glasses composites with QYs of 80 and 78%. The CDs/gel glasses show better transmittance in visible light bands and excellent thermal stability. A blue-pumped CDs/gel glasses phosphor-based trichromatic white light-emitting diode (WLED) is realized, whose color rendering index is 92.9. The WLED gets the highest luminous efficiency of 71.75 lm W -1 in CDs-based trichromatic WLEDs. This work opens a door for developing highly efficient green- and red-emissive switching CDs which were used as phosphors for WLEDs and have the tendency for applications in other fields, such as sensing, bioimaging, and photocatalysis.

A study of diverse clinical decision support rule authoring environments and requirements for integration

PubMed Central

2012-01-01

Background Efficient rule authoring tools are critical to allow clinical Knowledge Engineers (KEs), Software Engineers (SEs), and Subject Matter Experts (SMEs) to convert medical knowledge into machine executable clinical decision support rules. The goal of this analysis was to identify the critical success factors and challenges of a fully functioning Rule Authoring Environment (RAE) in order to define requirements for a scalable, comprehensive tool to manage enterprise level rules. Methods The authors evaluated RAEs in active use across Partners Healthcare, including enterprise wide, ambulatory only, and system specific tools, with a focus on rule editors for reminder and medication rules. We conducted meetings with users of these RAEs to discuss their general experience and perceived advantages and limitations of these tools. Results While the overall rule authoring process is similar across the 10 separate RAEs, the system capabilities and architecture vary widely. Most current RAEs limit the ability of the clinical decision support (CDS) interventions to be standardized, sharable, interoperable, and extensible. No existing system meets all requirements defined by knowledge management users. Conclusions A successful, scalable, integrated rule authoring environment will need to support a number of key requirements and functions in the areas of knowledge representation, metadata, terminology, authoring collaboration, user interface, integration with electronic health record (EHR) systems, testing, and reporting. PMID:23145874

Impact of a Commercially Available Clinical Decision Support Program on Provider Ordering Habits.

PubMed

Huber, Timothy C; Krishnaraj, Arun; Patrie, James; Gaskin, Cree M

2018-05-18

Clinical decision support (CDS) software designed around the ACR Appropriateness Criteria assists health care providers in choosing appropriate imaging studies at the time of order entry. The goal of this study was to determine the impact of commercially available CDS on the ordering habits of inpatient and emergency providers. In 2014, ACR Select was integrated into our electronic health record, though without displaying appropriateness scores in a "silent" mode for 6 months. Then, feedback regarding examination appropriateness was "turned on" at order entry for adult patients in the emergency and inpatient settings for 24 months. We retrospectively compared the appropriateness scores of imaging tests before and after displaying feedback at order entry and evaluated these data by modality and attending versus trainee status. The commercially available CDS-generated scores for 34% and 20.4% of pre- and postintervention studies, respectively. After feedback, the relative frequency of low utility studies decreased to 5.4% from 11%, and the relative frequency of indicated studies increased to 82% from 64.5%. This was most pronounced in trainees for whom the percentage of low utility studies decreased from 10.8% (95% confidence interval [CI]: 10.0%, 11.7%) to 4.8% (95% CI: 4.4%, 5.2%) and the percentage of indicated studies increased from 65.6% (95% CI: 64.3%, 66.9%) to 83.7% (83.0%, 84.3%). After implementation of a commercially available decision support tool integrated into the electronic health record, there was a significant improvement in imaging study appropriateness scores, more pronounced in studies ordered by trainees. Copyright © 2018 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Evaluation of a novel electronic genetic screening and clinical decision support tool in prenatal clinical settings.

PubMed

Edelman, Emily A; Lin, Bruce K; Doksum, Teresa; Drohan, Brian; Edelson, Vaughn; Dolan, Siobhan M; Hughes, Kevin; O'Leary, James; Vasquez, Lisa; Copeland, Sara; Galvin, Shelley L; DeGroat, Nicole; Pardanani, Setul; Gregory Feero, W; Adams, Claire; Jones, Renee; Scott, Joan

2014-07-01

"The Pregnancy and Health Profile" (PHP) is a free prenatal genetic screening and clinical decision support (CDS) software tool for prenatal providers. PHP collects family health history (FHH) during intake and provides point-of-care risk assessment for providers and education for patients. This pilot study evaluated patient and provider responses to PHP and effects of using PHP in practice. PHP was implemented in four clinics. Surveys assessed provider confidence and knowledge and patient and provider satisfaction with PHP. Data on the implementation process were obtained through semi-structured interviews with administrators. Quantitative survey data were analyzed using Chi square test, Fisher's exact test, paired t tests, and multivariate logistic regression. Open-ended survey questions and interviews were analyzed using qualitative thematic analysis. Of the 83% (513/618) of patients that provided feedback, 97% felt PHP was easy to use and 98% easy to understand. Thirty percent (21/71) of participating physicians completed both pre- and post-implementation feedback surveys [13 obstetricians (OBs) and 8 family medicine physicians (FPs)]. Confidence in managing genetic risks significantly improved for OBs on 2/6 measures (p values ≤0.001) but not for FPs. Physician knowledge did not significantly change. Providers reported value in added patient engagement and reported mixed feedback about the CDS report. We identified key steps, resources, and staff support required to implement PHP in a clinical setting. To our knowledge, this study is the first to report on the integration of patient-completed, electronically captured and CDS-enabled FHH software into primary prenatal practice. PHP is acceptable to patients and providers. Key to successful implementation in the future will be customization options and interoperability with electronic health records.

Vapor Compression and Thermoelectric Heat Pump Heat Exchangers for a Condensate Distillation System: Design and Experiment

NASA Technical Reports Server (NTRS)

Erickson, Lisa R.; Ungar, Eugene K.

2013-01-01

Maximizing the reuse of wastewater while minimizing the use of consumables is critical in long duration space exploration. One of the more promising methods of reclaiming urine is the distillation/condensation process used in the cascade distillation system (CDS). This system accepts a mixture of urine and toxic stabilizing agents, heats it to vaporize the water and condenses and cools the resulting water vapor. The CDS wastewater flow requires heating and its condensate flow requires cooling. Performing the heating and cooling processes separately requires two separate units, each of which would require large amounts of electrical power. By heating the wastewater and cooling the condensate in a single heat pump unit, mass, volume, and power efficiencies can be obtained. The present work describes and compares two competing heat pump methodologies that meet the needs of the CDS: 1) a series of mini compressor vapor compression cycles and 2) a thermoelectric heat exchanger. In the paper, the system level requirements are outlined, the designs of the two heat pumps are described in detail, and the results of heat pump performance tests are provided. A summary is provided of the heat pump mass, volume and power trades and a selection recommendation is made.

Blocking the Formation of Zn2+/Dye Complexes in Dye-Sensitized Solar Cells by Inserting CdS Quantum Dots into Sandwich Layer

NASA Astrophysics Data System (ADS)

Sun, Yunfei; Liu, Chunling; Yang, Lili; Wei, Maobin; Lv, Shiquan; Sui, Yingrui; Cao, Jian; Chen, Gang; Yang, Jinghai

2018-06-01

ZnO NRAs are grown on ITO substrates by a simple chemical method. CdS QDs were deposited on ZnO NRAs by SILAR. N719 was synthesized by dipping method. J-V analysis indicates that by inserting a layer of CdS QDs, the conversion efficiency of DSSCs was improved obviously. The device with CdS QDs shows the higher conversion efficiency due to the three reasons: (1) CdS QDs enhanced adsorption spectra of DSSCs in the visible region; (2) CdS QDs block the formation of Zn2+/dye complex, it is beneficial for electros transport from dye to ZnO photoanode. It is the key to obtain higher conversion efficiency; (3) FRET dynamics exists by the introduction of CdS QDs.

Facile and eco-friendly synthesis of green fluorescent carbon nanodots for applications in bioimaging, patterning and staining

NASA Astrophysics Data System (ADS)

Shi, Lihong; Li, Yanyan; Li, Xiaofeng; Wen, Xiangping; Zhang, Guomei; Yang, Jun; Dong, Chuan; Shuang, Shaomin

2015-04-01

We report a facile and eco-friendly strategy for the fabrication of green fluorescent carbon nanodots (CDs), and demonstrate their applications for bio-imaging, patterning, and staining. A one-pot hydrothermal method using various plant petals yields bright green-emitting CDs, providing an easy way for the production of green fluorescent CDs without the need for a tedious synthetic methodology or the use of toxic/expensive solvents and starting materials. The as-prepared CDs show small size distribution and excellent dispersibility. Their strong green fluorescence is observed when the excitation wavelength is between 430 nm and 490 nm. Moreover, they exhibit high tolerance to various external conditions, such as pH values, external cations, and continuous excitation. Due to minimum toxicity as well as good photoluminescence properties, these CDs can be applied to in vitro and in vivo imaging, patterning, and staining. According to confocal fluorescence imaging of human uterine cervical squamous cell carcinoma cells, CDs penetrate into the cell and enter the cytoplasm and the nucleus. More strikingly, carp is directly fed with CDs for in vivo imaging and shows bright green fluorescence at an excitation wavelength of 470 nm. In addition, the obtained CDs are used as fluorescent inks for drawing luminescence patterns. Finally, we also apply the CDs as a fluorescent dye. Interestingly, the absorbent filter paper with staining emits dramatic fluorescence under 470 nm excitation.We report a facile and eco-friendly strategy for the fabrication of green fluorescent carbon nanodots (CDs), and demonstrate their applications for bio-imaging, patterning, and staining. A one-pot hydrothermal method using various plant petals yields bright green-emitting CDs, providing an easy way for the production of green fluorescent CDs without the need for a tedious synthetic methodology or the use of toxic/expensive solvents and starting materials. The as-prepared CDs show small size distribution and excellent dispersibility. Their strong green fluorescence is observed when the excitation wavelength is between 430 nm and 490 nm. Moreover, they exhibit high tolerance to various external conditions, such as pH values, external cations, and continuous excitation. Due to minimum toxicity as well as good photoluminescence properties, these CDs can be applied to in vitro and in vivo imaging, patterning, and staining. According to confocal fluorescence imaging of human uterine cervical squamous cell carcinoma cells, CDs penetrate into the cell and enter the cytoplasm and the nucleus. More strikingly, carp is directly fed with CDs for in vivo imaging and shows bright green fluorescence at an excitation wavelength of 470 nm. In addition, the obtained CDs are used as fluorescent inks for drawing luminescence patterns. Finally, we also apply the CDs as a fluorescent dye. Interestingly, the absorbent filter paper with staining emits dramatic fluorescence under 470 nm excitation. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr00783f

Translation and validation of the Cardiac Depression Scale to Arabic.

PubMed

Papasavvas, T; Al-Amin, H; Ghabrash, H F; Micklewright, D

2016-08-01

The Cardiac Depression Scale (CDS) has been designed to measure depressive symptoms in patients with heart disease. There is no Arabic version of the CDS. We translated and validated the CDS in an Arabic sample of patients with heart disease. Forward and back translation of the CDS was followed by assessment of cultural relevance and content validity. The Arabic version of the CDS (A-CDS) and the Arabic version of the Hospital Anxiety and Depression Scale (A-HADS) were then administered to 260 Arab in-patients with heart disease from 18 Arabic countries. Construct validity was assessed using exploratory factor analysis with polychoric correlations. Internal consistency was assessed using ordinal reliability alpha and item-to-factor polychoric correlations. Concurrent validity was assessed using Pearson's correlation coefficient between the A-CDS and the depression subscale of the A-HADS (A-HADS-D). Cultural relevance and content validity of the A-CDS were satisfactory. Exploratory factor analysis revealed three robust factors, without cross-loadings, that formed a single dimension. Internal consistency was high (ordinal reliability alpha for the total scale and the three factors were .94, .91, .86, and .87, respectively; item-to-factor correlations ranged from .77 to .91). Concurrent validity was high (r=.72). The A-CDS demonstrated a closer to normal distribution of scores than the A-HADS-D. Sensitivity and specificity of the A-CDS were not objectively assessed. The A-CDS appears to be a valid and reliable instrument to measure depressive symptoms in a representative sample of Arab in-patients with heart disease. Copyright © 2016 Elsevier B.V. All rights reserved.

A 14-bit 40-MHz analog front end for CCD application

NASA Astrophysics Data System (ADS)

Jingyu, Wang; Zhangming, Zhu; Shubin, Liu

2016-06-01

A 14-bit, 40-MHz analog front end (AFE) for CCD scanners is analyzed and designed. The proposed system incorporates a digitally controlled wideband variable gain amplifier (VGA) with nearly 42 dB gain range, a correlated double sampler (CDS) with programmable gain functionality, a 14-bit analog-to-digital converter and a programmable timing core. To achieve the maximum dynamic range, the VGA proposed here can linearly amplify the input signal in a gain range from -1.08 to 41.06 dB in 6.02 dB step with a constant bandwidth. A novel CDS takes image information out of noise, and further amplifies the signal accurately in a gain range from 0 to 18 dB in 0.035 dB step. A 14-bit ADC is adopted to quantify the analog signal with optimization in power and linearity. An internal timing core can provide flexible timing for CCD arrays, CDS and ADC. The proposed AFE was fabricated in SMIC 0.18 μm CMOS process. The whole circuit occupied an active area of 2.8 × 4.8 mm2 and consumed 360 mW. When the frequency of input signal is 6.069 MHz, and the sampling frequency is 40 MHz, the signal to noise and distortion (SNDR) is 70.3 dB, the effective number of bits is 11.39 bit. Project supported by the National Natural Science Foundation of China (Nos. 61234002, 61322405, 61306044, 61376033), the National High-Tech Program of China (No. 2013AA014103), and the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory (No. ZHD201302).

Implementation of a Mobile Clinical Decision Support Application to Augment Local Antimicrobial Stewardship.

PubMed

Hoff, Brian M; Ford, Diana C; Ince, Dilek; Ernst, Erika J; Livorsi, Daniel J; Heintz, Brett H; Masse, Vincent; Brownlee, Michael J; Ford, Bradley A

2018-01-01

Medical applications for mobile devices allow clinicians to leverage microbiological data and standardized guidelines to treat patients with infectious diseases. We report the implementation of a mobile clinical decision support (CDS) application to augment local antimicrobial stewardship. We detail the implementation of our mobile CDS application over 20 months. Application utilization data were collected and evaluated using descriptive statistics to quantify the impact of our implementation. Project initiation focused on engaging key stakeholders, developing a business case, and selecting a mobile platform. The preimplementation phase included content development, creation of a pathway for content approval within the hospital committee structure, engaging clinical leaders, and formatting the first version of the guide. Implementation involved a media campaign, staff education, and integration within the electronic medical record and hospital mobile devices. The postimplementation phase required ongoing quality improvement, revision of outdated content, and repeated staff education. The evaluation phase included a guide utilization analysis, reporting to hospital leadership, and sustainability and innovation planning. The mobile application was downloaded 3056 times and accessed 9259 times during the study period. The companion web viewer was accessed 8214 times. Successful implementation of a customizable mobile CDS tool enabled our team to expand beyond microbiological data to clinical diagnosis, treatment, and antimicrobial stewardship, broadening our influence on antimicrobial prescribing and incorporating utilization data to inspire new quality and safety initiatives. Further studies are needed to assess the impact on antimicrobial utilization, infection control measures, and patient care outcomes.

Sustained inhibition of intimal thickening. In vitro and in vivo effects of polymeric beta-cyclodextrin sulfate.

PubMed Central

Bachinsky, W B; Barnathan, E S; Liu, H; Okada, S S; Kuo, A; Raghunath, P N; Muttreja, M; Caron, R J; Tomaszewski, J E; Golden, M A

1995-01-01

Intimal thickening after vascular injury may be modulated in part by heparin binding growth factors. We hypothesized that placement of a therapeutic polymer in the periadventitial space capable of tightly binding growth factors might alter the vascular response to injury. We first demonstrated that incubation of rat aortic smooth muscle cells with an insoluble, sulfated polymer of beta-cyclodextrin (P-CDS) was associated with a dose-dependent inhibition of proliferation induced by fetal calf serum, fibroblast growth factor-2 (FGF-2), platelet-derived growth factor BB, or epidermal growth factor. Preincubation studies of P-CDS with FGF-2 revealed a very rapid removal of mitogenic activity. Using radiolabeled FGF-2 (0.25 microg/ml), we observed a very rapid association rate (0.34 +/- 0.07 min-1, n=4) and a very slow dissociation rate (3.3 +/- 0.2 X 10(-7) min-1) at 37 degrees C, suggesting a high affinity interaction. Using both Transwell and linear under-agarose assays, we demonstrated a significant inhibition of random migration (chemokinesis) by P-CDS. Unsulfated polymeric beta-cyclodextrin (P-CD) had little if any of these effects, suggesting that the high negative charge density of P-CDS was important for the effects. Finally, rats undergoing carotid artery balloon injury were randomized to treatment with periadventitial P-CDS or no treatment, and were killed at 4 (n=20), 14 (n=59), and 88 d (n=14). Morphometric analysis demonstrated significant and sustained inhibition of intimal thickening in P-CDS-treated rats at 14 (P < 0.01) and 88 d (P < 0.05) using absolute intimal area or intima/media area ratios. No inhibition was seen in a group of rats treated with P-CD. In P-CDS-treated rats, bromodeoxyuridine labeling studies revealed fewer labeled smooth muscle cells in the intima at 14 d (P=0.01), while staining with Evans blue revealed enhanced late endothelial cell regrowth. Thus, periadventitially applied sulfated beta-cyclodextrin polymer, which can tightly bind heparin binding growth factors, inhibits intimal thickening in vivo in a sustained fashion without using an additional delivery system. These studies suggest that cellular processes mediated by heparin binding growth factors may be modulated by P-CDS. Images PMID:8675622

Facile synthesis of fluorescence carbon dots from sweet potato for Fe3+ sensing and cell imaging.

PubMed

Shen, Jie; Shang, Shaoming; Chen, Xiuying; Wang, Dan; Cai, Yan

2017-07-01

In this study, a facile synthesis of fluorescence carbon dots (CDs) from sweet potato was performed through hydrothermal treatment. The obtained CDs with quantum yield of 8.64% have good dispersibility due to the soluble functional groups on their surfaces. The characterization of CDs was carried out and their possible formation mechanism was also discussed. In addition, the cytotoxicity results showed that the CDs exhibit non toxicity within 100μg/mL. At this concentration, the CDs were applied in cell imaging, indicating that they are promising fluorescent probes for biological imaging. In addition, the fluorescence of CDs was quenched by Fe 3+ with a linear concentration of 1 to 100μM, associated with the limit of detection of 0.32μM. Subsequently, the CDs were successfully applied for Fe 3+ probing in living cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Red, green, and blue luminescence by carbon dots: full-color emission tuning and multicolor cellular imaging.

PubMed

Jiang, Kai; Sun, Shan; Zhang, Ling; Lu, Yue; Wu, Aiguo; Cai, Congzhong; Lin, Hengwei

2015-04-27

A facile approach for preparation of photoluminescent (PL) carbon dots (CDs) is reported. The three resulting CDs emit bright and stable red, green and blue (RGB) colors of luminescence, under a single ultraviolet-light excitation. Alterations of PL emission of these CDs are tentatively proposed to result from the difference in their particle size and nitrogen content. Interestingly, up-conversion (UC)PL of these CDs is also observed. Moreover, flexible full-color emissive PVA films can be achieved through mixing two or three CDs in the appropriate ratios. These CDs also show low cytotoxicity and excellent cellular imaging capability. The facile preparation and unique optical features make these CDs potentially useful in numerous applications such as light-emitting diodes, full-color displays, and multiplexed (UC)PL bioimaging. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Photo current generation in RGO - CdS nanorod thin film device

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chakraborty, Koushik; Chakrabarty, Sankalpita; Ibrahim, Sk.

2016-05-23

Herein, we report the synthesis and characterization of reduced graphene oxide (RGO) - cadmium sulfide (CdS) nanocomposite materials. The reduction of GO, formation of CdS and decoration of CdS onto RGO sheets were done in a one- pot solvothermal process. We have observed that the PL intensity for CdS nanorods remarkably quenched after the attachment of RGO, which established the photo induced charge transformation from the CdS nanorod to RGO sheets through the RGO-CdS interface. The optoelectronic transport properties of our fabricated large area thin film device exhibits excellent photo induced charge generation under simulated solar light illumination. The photomore » sensitivity of the device increases linearly with the increase of illuminated light intensity. The RGO-CdS composite exhibits enhance photocatalytic dye degradation efficiency in compare to control CdS under simulated solar light illumination.« less

A Second Life for CDs

ERIC Educational Resources Information Center

Snoderly, Kathleen

2011-01-01

Cutting a few CDs apart with scissors, the author found that the process created somewhat brittle shards. As a result, she started to paint a few with acrylic, finding to her amazement that the paint gave the CDs a leathery, more manageable texture. Upon further experimentation, she found that if the CDs are painted somewhat translucently in…

77 FR 13668 - Self-Regulatory Organizations; Chicago Mercantile Exchange, Inc.; Order Approving Proposed Rule...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-07

... calculates each CDS Clearing Member's allocation to the CDS Guaranty Fund, with a new standard that CME believes better allocates tail risk. Currently CME rules provide that each CDS Clearing Member's allocation... that the allocation will be made on the basis of each CDS Clearing Member's potential residual loss...

High fidelity polycrystalline CdTe/CdS heterostructures via molecular dynamics

DOE PAGES

Aguirre, Rodolfo; Chavez, Jose Juan; Zhou, Xiaowang; ...

2017-06-20

Molecular dynamics simulations of polycrystalline growth of CdTe/CdS heterostructures have been performed. First, CdS was deposited on an amorphous CdS substrate, forming a polycrystalline film. Subsequently, CdTe was deposited on top of the polycrystalline CdS film. Cross-sectional images show grain formation at early stages of the CdS growth. During CdTe deposition, the CdS structure remains almost unchanged. Concurrently, CdTe grain boundary motion was detected after the first 24.4 nanoseconds of CdTe deposition. With the elapse of time, this grain boundary pins along the CdS/CdTe interface, leaving only a small region of epitaxial growth. CdTe grains are larger than CdS grainsmore » in agreement with experimental observations in the literature. Crystal phase analysis shows that zinc blende structure dominates over the wurtzite structure inside both CdS and CdTe grains. Composition analysis shows Te and S diffusion to the CdS and CdTe films, respectively. Lastly, these simulated results may stimulate new ideas for studying and improving CdTe solar cell efficiency.« less

Carbon dots decorated magnetic ZnFe2O4 nanoparticles with enhanced adsorption capacity for the removal of dye from aqueous solution

NASA Astrophysics Data System (ADS)

Shi, Weilong; Guo, Feng; Wang, Huibo; Liu, Changan; Fu, Yijun; Yuan, Songliu; Huang, Hui; Liu, Yang; Kang, Zhenhui

2018-03-01

Widely used synthetic dyes have been caused serious environmental pollution. Therefore, it is imperative to acquire highly efficient adsorbent to remove them. Here, we report the carbon dots/ZnFe2O4 (CDs/ZFO) composites were prepared through a facile hydrothermal route for absorption removal of dye from aqueous solution. The characterizations reveal the CDs were uniformly deposited on the surfaces of ZFO nanoparticles in the composite. The CDs/ZFO composites as adsorbents exhibit enhanced adsorption behavior for methyl orange (MO) in comparison of pristine ZFO, in which the 5% CDs/ZFO (with the CDs mass content of 5 wt%) shows the highest absorption activity. Experimental studies on adsorption isotherms of MO over the 5% CDs/ZFO composite indicate that experimental data were found to follow Langmuir model with a monolayer adsorption capacity of 181.2 mg g-1. The corresponding adsorption kinetics was fitted well with the pseudo-second-order kinetic model. Moreover, thermodynamics parameters including ΔG°, ΔH° and ΔS° were tested, demonstrating that the adsorption of MO over CDs/ZFO composite was spontaneous and exothermic in nature. The remarkably increased adsorption performance of CDs/ZFO composites can be attributed to abundant oxygen-containing groups on the surface of CDs.

Effects of bacteria on CdS thin films used in technological devices

NASA Astrophysics Data System (ADS)

Alpdoğan, S.; Adıgüzel, A. O.; Sahan, B.; Tunçer, M.; Metin Gubur, H.

2017-04-01

Cadmium sulfide (CdS) thin films were fabricated on glass substrates by the chemical bath deposition method at 70 {}^\\circ \\text{C} considering deposition times ranging from 2 h to 5 h. The optical band gaps of CdS thin films were found to be in the 2.42-2.37 eV range. CdS thin films had uniform spherical nano-size grains which had polycrystalline, hexagonal and cubic phases. The films had a characteristic electrical resistivity of the order of {{10}5} Ω \\text{cm} and n-type conductivity at room condition. CdS thin films were incubated in cultures of B.domonas aeruginosa and Staphylococcus aureus, which exist abundantly in the environment, and form biofilms. SEM images showed that S. aureus and K. pneumonia were detected significantly on the film surfaces with a few of P. aeruginosa and B. subtilis cells attached. CdS thin film surface exhibits relatively good resistance to the colonization of P. aeruginosa and B. subtilis. Optical results showed that the band gap of CdS thin films which interacted with the bacteria is 2.42 \\text{eV} . The crystal structure and electrical properties of CdS thin films were not affected by bacterial adhesion. The antimicrobial effect of CdS nanoparticles was different for different bacterial strains.

Controllable synthesis of green and blue fluorescent carbon nanodots for pH and Cu(2+) sensing in living cells.

PubMed

Shi, Lihong; Li, Yanyan; Li, Xiaofeng; Zhao, Bo; Wen, Xiangping; Zhang, Guomei; Dong, Chuan; Shuang, Shaomin

2016-03-15

We report a controllable strategy for fabrication of green and blue fluorescent carbon nanodots (CDs), and demonstrate their applications for pH and Cu(2+) sensing in living cells. Green and blue fluorescent CDs have been synthesized by hydrothermal method and pyrolysis of leeks, respectively, providing an easy way for the production of CDs without the request of tedious synthetic methodology or the use of toxic/expensive solvents and starting materials. Green fluorescent CDs (G-CDs) exhibit high tolerance to pH values and external cations. Blue fluorescent CDs (B-CDs) can be applied to pH and Cu(2+) sensing. The linear range of Cu(2+) detection is 0.01-10.00 μM and the detection limit is 0.05 μM. For pH detection, there is a good linearity in the pH range of 3.5-10.0. The linear and rapid response of B-CDs to Cu(2+) and pH is valuable for Cu(2+) and pH sensing in living cells. Confocal fluorescent imaging of human cervical carcinoma cells indicates that B-CDs could visualize Cu(2+) and pH fluctuations in living cells with negligible autofluorescence. Copyright © 2015 Elsevier B.V. All rights reserved.

In vivo characterization of hair and skin derived carbon quantum dots with high quantum yield as long-term bioprobes in zebrafish

PubMed Central

Zhang, Jing-Hui; Niu, Aping; Li, Jing; Fu, Jian-Wei; Xu, Qun; Pei, De-Sheng

2016-01-01

Carbon quantum dots (CDs) were widely investigated because of their tunable fluorescence properties and low toxicity. However, so far there have been no reports on in vivo functional studies of hair and skin derived CDs. Here, hair derived CDs (HCDs) and skin derived CDs (SCDs) were produced by using human hair and pig skin as precursors. The quantum yields (QYs) of HCDs and SCDs were quite high, compared to citric acid derived CDs (CCDs). HCDs and SCDs possess optimal photostability, hypotoxicity and biocompatibility in zebrafish, indicating that HCDs and SCDs possess the capacity of being used as fluorescence probes for in vivo biological imaging. The long-time observation for fluorescence alternation of CDs in zebrafish and the quenching assay of CDs by ATP, NADH and Fe3+ ions demonstrated that the decaying process of CDs in vivo might be induced by the synergistic effect of the metabolism process. All results indicated that large batches and high QYs of CDs can be acquired by employing natural and nontoxic hair and skin as precursors. To our knowledge, this is the first time to report SCDs, in vivo comparative studies of HCDs, SCDs and CCDs as bioprobes, and explore their mechanism of photostability in zebrafish. PMID:27886267

In vivo characterization of hair and skin derived carbon quantum dots with high quantum yield as long-term bioprobes in zebrafish.

PubMed

Zhang, Jing-Hui; Niu, Aping; Li, Jing; Fu, Jian-Wei; Xu, Qun; Pei, De-Sheng

2016-11-25

Carbon quantum dots (CDs) were widely investigated because of their tunable fluorescence properties and low toxicity. However, so far there have been no reports on in vivo functional studies of hair and skin derived CDs. Here, hair derived CDs (HCDs) and skin derived CDs (SCDs) were produced by using human hair and pig skin as precursors. The quantum yields (QYs) of HCDs and SCDs were quite high, compared to citric acid derived CDs (CCDs). HCDs and SCDs possess optimal photostability, hypotoxicity and biocompatibility in zebrafish, indicating that HCDs and SCDs possess the capacity of being used as fluorescence probes for in vivo biological imaging. The long-time observation for fluorescence alternation of CDs in zebrafish and the quenching assay of CDs by ATP, NADH and Fe 3+ ions demonstrated that the decaying process of CDs in vivo might be induced by the synergistic effect of the metabolism process. All results indicated that large batches and high QYs of CDs can be acquired by employing natural and nontoxic hair and skin as precursors. To our knowledge, this is the first time to report SCDs, in vivo comparative studies of HCDs, SCDs and CCDs as bioprobes, and explore their mechanism of photostability in zebrafish.

In vivo characterization of hair and skin derived carbon quantum dots with high quantum yield as long-term bioprobes in zebrafish

NASA Astrophysics Data System (ADS)

Zhang, Jing-Hui; Niu, Aping; Li, Jing; Fu, Jian-Wei; Xu, Qun; Pei, De-Sheng

2016-11-01

Carbon quantum dots (CDs) were widely investigated because of their tunable fluorescence properties and low toxicity. However, so far there have been no reports on in vivo functional studies of hair and skin derived CDs. Here, hair derived CDs (HCDs) and skin derived CDs (SCDs) were produced by using human hair and pig skin as precursors. The quantum yields (QYs) of HCDs and SCDs were quite high, compared to citric acid derived CDs (CCDs). HCDs and SCDs possess optimal photostability, hypotoxicity and biocompatibility in zebrafish, indicating that HCDs and SCDs possess the capacity of being used as fluorescence probes for in vivo biological imaging. The long-time observation for fluorescence alternation of CDs in zebrafish and the quenching assay of CDs by ATP, NADH and Fe3+ ions demonstrated that the decaying process of CDs in vivo might be induced by the synergistic effect of the metabolism process. All results indicated that large batches and high QYs of CDs can be acquired by employing natural and nontoxic hair and skin as precursors. To our knowledge, this is the first time to report SCDs, in vivo comparative studies of HCDs, SCDs and CCDs as bioprobes, and explore their mechanism of photostability in zebrafish.

CdS-sensitized TiO2 nanocorals: hydrothermal synthesis, characterization, application.

PubMed

Mali, S S; Desai, S K; Dalavi, D S; Betty, C A; Bhosale, P N; Patil, P S

2011-10-01

Cadmium sulfide (CdS) nanoparticle-sensitized titanium oxide nanocorals (TNC) were synthesized using a two-step deposition process. The TiO(2) nanocorals were grown on the conducting glass substrates (FTO) using A hydrothermal process and CdS nanoparticles were loaded on TNC using successive ionic layer adsorption and reaction (SILAR) method. The TiO(2), CdS and TiO(2)-CdS samples were characterized by optical absorption, X-ray diffraction (XRD), FT-Raman, FT-IR, scanning electron microscopy (SEM) and contact angle. Further, their photoelectrochemical (PEC) performance was tested in NaOH, Na(2)S-NaOH-S and Na(2)S electrolytes, respectively. When CdS nanoparticles are coated on TNCs, the optical absorption is found to be enhanced and band edge is red-shifted towards visible region. The TiO(2)-CdS sample exhibits improved photoelectrochemical (PEC) performance with maximum short circuit current of (J(sc)) 1.04 mA cm(-2). After applying these TiO(2)-CdS electrodes in photovoltaic cells, the photocurrent was found to be enhanced by 2.7 and 32.5 times, as compared with those of bare CdS and TiO(2) nanocorals films electrodes respectively. Also, the power conversion efficiency of TiO(2)-CdS electrodes is 0.72%, which is enhanced by about 16 and 29 times for TiO(2), CdS samples. This journal is © The Royal Society of Chemistry and Owner Societies 2011

Label-free fluorimetric detection of CEA using carbon dots derived from tomato juice.

PubMed

Miao, Hong; Wang, Lan; Zhuo, Yan; Zhou, Zinan; Yang, Xiaoming

2016-12-15

A facile-green strategy to synthesize carbon dots (CDs) with a quantum yield (QY) of nearly 13.9% has been built up, while tomato juice served as the carbon source. Interestingly, not only the precursor of CDs and the whole synthesis procedure were environmental-friendly, but this type of CDs also exhibited multiple advantages including high fluorescent QY, excellent photostability, non-toxicity and satisfactory stability. Significantly, a label-free sensitive assay for detecting carcinoembryonic antigen (CEA) in a continuous and recyclable way has been proposed on the basis of adsorption and desorption of aptamers by the surface of CDs through a competitive mechanism. To be specific, the richness of carboxyl groups of the CDs enabled strong adsorption of ssDNA to the surface of CDs through π-π stacking interactions, resulting in the effective fluorescence quenching by forming CDs-aptamer complexes. The stronger binding affinity between CEA and CEA-aptamer than the π-π stacking interactions has been taken advantage to achieve immediate recovery of the fluorescence of CDs once CEA was introduced. Thereby, quantitative evaluation of CEA concentration in a broad range from 1ngmL(-1) to 0.5ngmL(-1) with the detection limit of 0.3ngmL(-1) was realized in this way. This strategy can be applied in a recyclable way, broadening the sensing application of CDs with biocompatibility. Besides, the CDs were used for cell imaging, potentiating them towards diverse purposes. Copyright © 2016 Elsevier B.V. All rights reserved.

Growth and characterization of CdS buffer layers by CBD and MOCVD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morrone, A.A.; Huang, C.; Li, S.S.

1999-03-01

Thin film CdS has been widely used in thin-film photovoltaic devices. The most efficient Cu(In,&hthinsp;Ga)Se{sub 2} (CIGS) solar cells reported to date utilized a thin CdS buffer layer prepared by a reactive solution growth technique known as chemical bath deposition (CBD). Considerable effort has been directed to better understand the role and find a replacement for the CBD CdS process in CIGS-based solar cells. We reported a low temperature ({approximately}150&hthinsp;{degree}C) Metalorganic Chemical Vapor Deposition (MOCVD) CdS thin film buffer layer process for CIGS absorbers. Many prior studies have reported that CBD CdS contains a mixture of crystal structures. Recent investigationsmore » of CBD CdS thin films by ellipsometry suggested a multilayer structure. In this study we compare CdS thin films prepared by CBD and MOCVD and the effects of annealing. TED and XRD are used to characterize the crystal structure, the film microstructure is studied by HRTEM, and the optical properties are studied by Raman and spectrophotometry. All of these characterization techniques reveal superior crystalline film quality for CdS films grown by MOCVD compared to those grown by CBD. Dual Beam Optical Modulation (DBOM) studies showed that the MOCVD and CBD CdS buffer layer processes have nearly the same effect on CIGS absorbers when combined with a cadmium partial electrolyte aqueous dip. {copyright} {ital 1999 American Institute of Physics.}« less

High Performance Photoluminescent Carbon Dots for In Vitro and In Vivo Bioimaging: Effect of Nitrogen Doping Ratios.

PubMed

Wang, Junqing; Zhang, Pengfei; Huang, Chao; Liu, Gang; Leung, Ken Cham-Fai; Wáng, Yì Xiáng J

2015-07-28

Photoluminescent carbon dots (CDs) have received ever-increasing attention in the application of optical bioimaging because of their low toxicity, tunable fluorescent properties, and ultracompact size. We report for the first time on enhanced photoluminescence (PL) performance influenced by structure effects among the various types of nitrogen doped (N-doped) PL CDs. These CDs were facilely synthesized from condensation carbonization of linear polyethylenic amine (PEA) analogues and citric acid (CA) of different ratios. Detailed structural and property studies demonstrated that either the structures or the molar ratio of PEAs altered the PL properties of the CDs. The content of conjugated π-domains with C═N in the carbon backbone was correlated with their PL Quantum Yield (QY) (up to 69%). The hybridization between the surface/molecule state and the carbon backbone synergistically affected the chemical/physical properties. Also, long-chain polyethylenic amine (PEA) molecule-doped CDs exhibit increasing photostability, but at the expense of PL efficiency, proving that the PL emission of high QY CDs arise not only from the sp(2)/sp(3) carbon core and surface passivation of CDs, but also from the molecular fluorophores integrated in the CDs. In vitro and in vivo bioimaging of these N-doped CDs showed strong photoluminescence signals. Good biocompatibility demonstrates their potential feasibility for bioimaging applications. In addition, the overall size profile of the as-prepared CDs is comparable to the average size of capillary pores in normal living tissues (∼5 nm). Our study provides valuable insights into the effects of the PEA doping ratios on photoluminescence efficiency, biocompatibility, cellular uptake, and optical bioimaging of CDs.

Chemically Deposited CdS Buffer/Kesterite Cu2ZnSnS4 Solar Cells: Relationship between CdS Thickness and Device Performance.

PubMed

Hong, Chang Woo; Shin, Seung Wook; Suryawanshi, Mahesh P; Gang, Myeng Gil; Heo, Jaeyeong; Kim, Jin Hyeok

2017-10-25

Earth-abundant, copper-zinc-tin-sulfide (CZTS), kesterite, is an attractive absorber material for thin-film solar cells (TFSCs). However, the open-circuit voltage deficit (V oc -deficit) resulting from a high recombination rate at the buffer/absorber interface is one of the major challenges that must be overcome to improve the performance of kesterite-based TFSCs. In this paper, we demonstrate the relationship between device parameters and performances for chemically deposited CdS buffer/CZTS-based heterojunction TFSCs as a function of buffer layer thickness, which could change the CdS/CZTS interface conditions such as conduction band or valence band offsets, to gain deeper insight and understanding about the V oc -deficit behavior from a high recombination rate at the CdS buffer/kesterite interface. Experimental results show that device parameters and performances are strongly dependent on the CdS buffer thickness. We postulate two meaningful consequences: (i) Device parameters were improved up to a CdS buffer thickness of 70 nm, whereas they deteriorated at a thicker CdS buffer layer. The V oc -deficit in the solar cells improved up to a CdS buffer thickness of 92 nm and then deteriorated at a thicker CdS buffer layer. (ii) The minimum values of the device parameters were obtained at 70 nm CdS thickness in the CZTS TFSCs. Finally, the highest conversion efficiency of 8.77% (V oc : 494 mV, J sc : 34.54 mA/cm 2 , and FF: 51%) is obtained by applying a 70 nm thick CdS buffer to the Cu 2 ZnSn(S,Se) 4 absorber layer.

Synthesis of CdS nanorods in soft template under gamma-irradiation.

PubMed

Zhao, Bing; Wang, Yanli; Zhang, Haijiao; Jiao, Zheng; Wang, Haobo; Ding, Guoji; Wu, Minghong

2009-02-01

CdS nano material which has a band gap of 2.42 eV at room temperature is a typical II-VII semiconductor having many commercial or potential applications, e.g., light-emitting diodes, solar cell and optoelectronic devices. In this paper, we use a new strategy to synthesize CdS nanorods. CdS nanorods were prepared in soft template under gamma-irradiation though the reaction of cadmium sulphide and thiacetamide (TAA). The formation process and characters of CdS nanorods was investigated in detail by transmission electron microscopy (TEM), electron diffraction (ED) pattern, X-ray powder diffraction (XRD), ultraviolet spectrophotometer (UV) and photoluminescence spectrophotometer (PL). In the experiment we proposed that the irradiation of gamma-ray accelerated the formation of S(2-) under acidic condition (pH = 3) and vinyl acetate (VAc) monomer formed pre-organized nano polymer tubules which were used as both templates and nanoreacters for the growth of CdS nanorods. In this process, we have obtained the CdS polycrystal nanorods with PVAc nano tubules and CdS single-crystal nanorods. The result of X-ray powder diffraction confirms that the crystal type of CdS nanorods is cubic F-43 m (216). The results from transmission electron microscopy and electron diffraction show that the concentrations of reactants and the dose rate of gamma-ray are key to produce appropriate CdS nanorods. Relatively low concentrations (Cd2+: 0.008-0.02 mol/L, Cd2+ : S(2-) = 1 : 2) of reactants and long time (1-2 d) of irradiation in low dose rate (6-14 Gy/min) are propitious to form CdS single-crystal nanorods with small diameter (less than 100 nm) and well length (2-5 microm). UV and PL characterizations show the sample have well optical properties.

Nitrogen-doped carbon dots originating from unripe peach for fluorescent bioimaging and electrocatalytic oxygen reduction reaction.

PubMed

Atchudan, Raji; Edison, Thomas Nesakumar Jebakumar Immanuel; Lee, Yong Rok

2016-11-15

This paper reports the robust hydrothermal synthesis of nitrogen doped carbon dots (N-CDs) using the unripe fruit of Prunus persica (peach) as the carbon precursor and aqueous ammonia as the nitrogen source. The optical properties of synthesized N-CDs were characterized by ultraviolet visible (UV-Vis) and fluorescence spectroscopy techniques. The synthesized N-CDs were emitted blue light when excitated with a portable UV lamp. The materials with the optical properties were characterized further by high resolution transmission electron microscope (HRTEM), X-ray diffraction (XRD), Raman, Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS). The mean size of the N-CDs was approximately 8nm, as calculated from the HRTEM image. The d-spacing of N-CDs, calculated using Bragg law, was approximately 0.21nm, which was consistent with the interlayer distance calculated from the HRTEM image. FT-IR spectroscopy and XPS revealed the presence of the phytoconstituents functionalities of peach fruit over the N-CDs surface and a high level of nitrogen doping on carbon dots (CDs) was confirmed by XPS studies. These results suggest that the unripe fruit extract of peach is an ideal candidate for the preparation of N-CDs. The resulting N-CDs showed excellent optical properties in water. The synthesized N-CDs exhibited a high fluorescence quantum yield and low cytotoxicity, and can be used as fluorescence imaging probes. In addition, the N-CDs were catalytically activite towards the oxygen reduction reaction (ORR). The N-CDs exhibited good catalytic activity in an alkaline medium (0.1M KOH) with a remarkable ORR of approximately 0.72V vs reversible hydrogen electrode (RHE), and O2 reduction follows mainly a 2 electron pathway by being reduced to hydrogen peroxide. The 2-electron reduction pathway is used in industry for H2O2 production. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluating the effect of a web-based quality improvement system with feedback and outreach visits on guideline concordance in the field of cardiac rehabilitation: rationale and study protocol.

PubMed

van Engen-Verheul, Mariëtte M; de Keizer, Nicolette F; van der Veer, Sabine N; Kemps, Hareld M C; Scholte op Reimer, Wilma J M; Jaspers, Monique W M; Peek, Niels

2014-12-31

Implementation of clinical practice guidelines into daily care is hampered by a variety of barriers related to professional knowledge and collaboration in teams and organizations. To improve guideline concordance by changing the clinical decision-making behavior of professionals, computerized decision support (CDS) has been shown to be one of the most effective instruments. However, to address barriers at the organizational level, additional interventions are needed. Continuous monitoring and systematic improvement of quality are increasingly used to achieve change at this level in complex health care systems. The study aims to assess the effectiveness of a web-based quality improvement (QI) system with indicator-based performance feedback and educational outreach visits to overcome organizational barriers for guideline concordance in multidisciplinary teams in the field of cardiac rehabilitation (CR). A multicenter cluster-randomized trial with a balanced incomplete block design will be conducted in 18 Dutch CR clinics using an electronic patient record with CDS at the point of care. The intervention consists of (i) periodic performance feedback on quality indicators for CR and (ii) educational outreach visits to support local multidisciplinary QI teams focussing on systematically improving the care they provide. The intervention is supported by a web-based system which provides an overview of the feedback and facilitates development and monitoring of local QI plans. The primary outcome will be concordance to national CR guidelines with respect to the CR needs assessment and therapy indication procedure. Secondary outcomes are changes in performance of CR clinics as measured by structure, process and outcome indicators, and changes in practice variation on these indicators. We will also conduct a qualitative process evaluation (concept-mapping methodology) to assess experiences from participating CR clinics and to gain insight into factors which influence the implementation of the intervention. To our knowledge, this will be the first study to evaluate the effect of providing performance feedback with a web-based system that incorporates underlying QI concepts. The results may contribute to improving CR in the Netherlands, increasing knowledge on facilitators of guideline implementation in multidisciplinary health care teams and identifying success factors of multifaceted feedback interventions. NTR3251.

Usability Evaluation of a Clinical Decision Support System for Geriatric ED Pain Treatment.

PubMed

Genes, Nicholas; Kim, Min Soon; Thum, Frederick L; Rivera, Laura; Beato, Rosemary; Song, Carolyn; Soriano, Jared; Kannry, Joseph; Baumlin, Kevin; Hwang, Ula

2016-01-01

Older adults are at risk for inadequate emergency department (ED) pain care. Unrelieved acute pain is associated with poor outcomes. Clinical decision support systems (CDSS) hold promise to improve patient care, but CDSS quality varies widely, particularly when usability evaluation is not employed. To conduct an iterative usability and redesign process of a novel geriatric abdominal pain care CDSS. We hypothesized this process would result in the creation of more usable and favorable pain care interventions. Thirteen emergency physicians familiar with the Electronic Health Record (EHR) in use at the study site were recruited. Over a 10-week period, 17 1-hour usability test sessions were conducted across 3 rounds of testing. Participants were given 3 patient scenarios and provided simulated clinical care using the EHR, while interacting with the CDSS interventions. Quantitative System Usability Scores (SUS), favorability scores and qualitative narrative feedback were collected for each session. Using a multi-step review process by an interdisciplinary team, positive and negative usability issues in effectiveness, efficiency, and satisfaction were considered, prioritized and incorporated in the iterative redesign process of the CDSS. Video analysis was used to determine the appropriateness of the CDS appearances during simulated clinical care. Over the 3 rounds of usability evaluations and subsequent redesign processes, mean SUS progressively improved from 74.8 to 81.2 to 88.9; mean favorability scores improved from 3.23 to 4.29 (1 worst, 5 best). Video analysis revealed that, in the course of the iterative redesign processes, rates of physicians' acknowledgment of CDS interventions increased, however most rates of desired actions by physicians (such as more frequent pain score updates) decreased. The iterative usability redesign process was instrumental in improving the usability of the CDSS; if implemented in practice, it could improve geriatric pain care. The usability evaluation process led to improved acknowledgement and favorability. Incorporating usability testing when designing CDSS interventions for studies may be effective to enhance clinician use.

Phase- and shape-controlled hydrothermal synthesis of CdS nanoparticles, and oriented attachment growth of its hierarchical architectures

NASA Astrophysics Data System (ADS)

Cao, Yali; Hu, Pengfei; Jia, Dianzeng

2013-01-01

Hydrothermal strategies were successfully used to control the phases and morphologies of CdS nanocrystals. In the absence of an external direction-controlling process, the hexagonal and cubic phase well-defined leaf- and flower-like CdS nanocrystals were controlled obtained via adjusting the reaction duration or the concentration of surfactant. Oriented attachment growth modes were suggested for the formation of CdS superstructures, which was clarified through the tracing of temporal evolution of CdS nanoparticles. The CdS superstructures were structured by primary building nanoparticles, and held excellent visible emission with a peak in the green regions. This strategy is very helpful for studying the phase and morphology controlled fabrication of sulfides nanocrystals.

Biomimetic synthesis of needle-like fluorescent calcium phosphate/carbon dot hybrid composites for cell labeling and copper ion detection.

PubMed

Guo, Shanshan; Lu, Shousi; Xu, Pingxiang; Ma, Yi; Zhao, Liang; Zhao, Yuming; Gu, Wei; Xue, Ming

2016-05-04

Herein, we report a biomimetic method to synthesize needle-like calcium phosphate (CaP) with dimensions of ∼130 nm length and ∼30 nm width using carbon dots (CDs) and sodium carboxymethylcellulose as dual templates. In addition to acting as the template, the CDs enable the CaP/CDs hybrid composites to emit blue fluorescence under UV excitation. Moreover, the prepared CaP/CDs exhibited a negligible cytotoxicity towards HeLa cells. The potential of these CaP/CDs as a fluorescent probe for cell labeling was tested. In addition, it was demonstrated that the CaP/CDs were capable of selective detection of copper ions in drinking water.

Biosynthesis of CdS nanoparticles in banana peel extract.

PubMed

Zhou, Guang Ju; Li, Shuo Hao; Zhang, Yu Cang; Fu, Yun Zhi

2014-06-01

Cadmium sulfide (CdS) nanoparticles (NPs) were synthesized by using banana peel extract as a convenient, non-toxic, eco-friendly 'green' capping agent. Cadmium nitrate and sodium sulfide are main reagents. A variety of CdS NPs are prepared through changing reaction conditions (banana extracts, the amount of banana peel extract, solution pH, concentration and reactive temperature). The prepared CdS colloid displays strong fluorescence spectrum. X-ray diffraction analysis demonstrates the successful formation of CdS NPs. Fourier transform infra-red (FTIR) spectrogram indicates the involvement of carboxyl, amine and hydroxyl groups in the formation of CdS NPs. Transmission electron microscope (TEM) result reveals that the average size of the NPs is around 1.48 nm.

Unique organogel formation with macroporous materials constructed by the freeze-drying of aqueous cyclodextrin solutions.

PubMed

Marui, Yasuhiro; Kikuzawa, Akira; Kida, Toshiyuki; Akashi, Mitsuru

2010-07-06

Macroporous cyclodextrin materials (MP-alpha-, beta-, and gamma-CDs) were easily fabricated by the freeze-drying of aqueous solutions of alpha-, beta-, and gamma-CDs. These MP-CDs showed the absorption ability toward various organic solvents and oils to give organogels at ambient temperature. The morphological changes of the MP-CD microstructures were observed through the absorption of organic solvents. In particular, the absorption of polar organic solvents with hydrogen-bond forming ability, including 1,4-dioxane and ethanol, by the MP-CDs caused remarkable morphological changes in the microstructures. The absorption of these polar solvents by MP-alpha- and gamma-CDs resulted in the formation of channel-type assemblies of alpha- and gamma-CDs, respectively.

Mn(II)-coordinated Fluorescent Carbon Dots: Preparation and Discrimination of Organic Solvents

NASA Astrophysics Data System (ADS)

Wang, Yuru; Wang, Tianren; Chen, Xi; Xu, Yang; Li, Huanrong

2018-04-01

Herein, we prepared a Mn(II)-coordinated carbon dots (CDs) with fluorescence and MRI (magnetic resonance imaging) bimodal properties by a one-pot solvothermal method and separated via silica column chromatography. The quantum yield of the CDs increased greatly from 2.27% to 6.75% with increase of Mn(II) doping, meanwhile the CDs exhibited a higher MR activity (7.28 mM-1s-1) than that of commercial Gd-DTPA (4.63 mM-1s-1). In addition, white light emitting CDs were obtained by mixing the different types of CDs. Notably, these CDs exhibited different fluorescence emissions in different organic solvents and could be used to discriminate organic solvents based on the polarity and protonation of the solvents.

Learning Healthcare System for the Prescription of Genetic Testing in the Gynecological Cancer Risk.

PubMed

Suárez-Mejías, Cristina; Martínez-García, Alicia; Martínez-Maestre, María Ángeles; Silvan-Alfaro, José Manuel; Moreno Conde, Jesús; Parra-Calderón, Carlos Luis

2017-01-01

Clinical evidence demonstrates that BRCA 1 and BRCA2 mutations can develop a gynecological cancer but genetic testing has a high cost to the healthcare system. Besides, several studies in the literature indicate that performing these genetic tests to the population is not cost-efficient. Currently, our physicians do not have a system to provide them the support for prescribing genetic tests. A Decision Support System for prescribing these genetic tests in BRCA1 and BRCA2 and preventing gynecological cancer risks has been designed, developed and deployed in the Virgen del Rocío University Hospital (VRUH). The technological architecture integrates a set of open source tools like Mirth Connect, OpenClinica, OpenCDS, and tranSMART in addition to several interoperability standards. The system allows general practitioners and gynecologists to classify patients as low risk (they do not require a specific treatment) or high risk (they should be attended by the Genetic Council). On the other hand, by means of this system we are also able to standardize criteria among professionals to prescribe these genetic tests. Finally, this system will also contribute to improve the assistance for this kind of patients.

Dynamic Modeling of Process Technologies for Closed-Loop Water Recovery Systems

NASA Technical Reports Server (NTRS)

Allada, Rama Kumar; Lange, Kevin E.; Anderson, Molly S.

2012-01-01

Detailed chemical process simulations are a useful tool in designing and optimizing complex systems and architectures for human life support. Dynamic and steady-state models of these systems help contrast the interactions of various operating parameters and hardware designs, which become extremely useful in trade-study analyses. NASA s Exploration Life Support technology development project recently made use of such models to compliment a series of tests on different waste water distillation systems. This paper presents dynamic simulations of chemical process for primary processor technologies including: the Cascade Distillation System (CDS), the Vapor Compression Distillation (VCD) system, the Wiped-Film Rotating Disk (WFRD), and post-distillation water polishing processes such as the Volatiles Removal Assembly (VRA). These dynamic models were developed using the Aspen Custom Modeler (Registered TradeMark) and Aspen Plus(Registered TradeMark) process simulation tools. The results expand upon previous work for water recovery technology models and emphasize dynamic process modeling and results. The paper discusses system design, modeling details, and model results for each technology and presents some comparisons between the model results and available test data. Following these initial comparisons, some general conclusions and forward work are discussed.

Minimum entropy principle-based solar cell operation without a pn-junction and a thin CdS layer to extract the holes from the emitter

NASA Astrophysics Data System (ADS)

Böer, Karl W.

2016-10-01

The solar cell does not use a pn-junction to separate electrons from holes, but uses an undoped CdS layer that is p-type inverted when attached to a p-type collector and collects the holes while rejecting the backflow of electrons and thereby prevents junction leakage. The operation of the solar cell is determined by the minimum entropy principle of the cell and its external circuit that determines the electrochemical potential, i.e., the Fermi-level of the base electrode to the operating (maximum power point) voltage. It leaves the Fermi level of the metal electrode of the CdS unchanged, since CdS does not participate in the photo-emf. All photoelectric actions are generated by the holes excited from the light that causes the shift of the quasi-Fermi levels in the generator and supports the diffusion current in operating conditions. It is responsible for the measured solar maximum power current. The open circuit voltage (Voc) can approach its theoretical limit of the band gap of the collector at 0 K and the cell increases the efficiency at AM1 to 21% for a thin-film CdS/CdTe that is given as an example here. However, a series resistance of the CdS forces a limitation of its thickness to preferably below 200 Å to avoid unnecessary reduction in efficiency or Voc. The operation of the CdS solar cell does not involve heated carriers. It is initiated by the field at the CdS/CdTe interface that exceeds 20 kV/cm that is sufficient to cause extraction of holes by the CdS that is inverted to become p-type. Here a strong doubly charged intrinsic donor can cause a negative differential conductivity that switches-on a high-field domain that is stabilized by the minimum entropy principle and permits an efficient transport of the holes from the CdTe to the base electrode. Experimental results of the band model of CdS/CdTe solar cells are given and show that the conduction bands are connected in the dark, where the electron current must be continuous, and the valence bands are connected with light where the hole currents are dominant and must be continuous through the junction. The major shifts of the bands in operating conditions are self-adjusting by a change in the junction dipole momentum.

Acoustic-Emergent Phonology in the Amplitude Envelope of Child-Directed Speech

PubMed Central

Leong, Victoria; Goswami, Usha

2015-01-01

When acquiring language, young children may use acoustic spectro-temporal patterns in speech to derive phonological units in spoken language (e.g., prosodic stress patterns, syllables, phonemes). Children appear to learn acoustic-phonological mappings rapidly, without direct instruction, yet the underlying developmental mechanisms remain unclear. Across different languages, a relationship between amplitude envelope sensitivity and phonological development has been found, suggesting that children may make use of amplitude modulation (AM) patterns within the envelope to develop a phonological system. Here we present the Spectral Amplitude Modulation Phase Hierarchy (S-AMPH) model, a set of algorithms for deriving the dominant AM patterns in child-directed speech (CDS). Using Principal Components Analysis, we show that rhythmic CDS contains an AM hierarchy comprising 3 core modulation timescales. These timescales correspond to key phonological units: prosodic stress (Stress AM, ~2 Hz), syllables (Syllable AM, ~5 Hz) and onset-rime units (Phoneme AM, ~20 Hz). We argue that these AM patterns could in principle be used by naïve listeners to compute acoustic-phonological mappings without lexical knowledge. We then demonstrate that the modulation statistics within this AM hierarchy indeed parse the speech signal into a primitive hierarchically-organised phonological system comprising stress feet (proto-words), syllables and onset-rime units. We apply the S-AMPH model to two other CDS corpora, one spontaneous and one deliberately-timed. The model accurately identified 72–82% (freely-read CDS) and 90–98% (rhythmically-regular CDS) stress patterns, syllables and onset-rime units. This in-principle demonstration that primitive phonology can be extracted from speech AMs is termed Acoustic-Emergent Phonology (AEP) theory. AEP theory provides a set of methods for examining how early phonological development is shaped by the temporal modulation structure of speech across languages. The S-AMPH model reveals a crucial developmental role for stress feet (AMs ~2 Hz). Stress feet underpin different linguistic rhythm typologies, and speech rhythm underpins language acquisition by infants in all languages. PMID:26641472

Acoustic-Emergent Phonology in the Amplitude Envelope of Child-Directed Speech.

PubMed

Leong, Victoria; Goswami, Usha

2015-01-01

When acquiring language, young children may use acoustic spectro-temporal patterns in speech to derive phonological units in spoken language (e.g., prosodic stress patterns, syllables, phonemes). Children appear to learn acoustic-phonological mappings rapidly, without direct instruction, yet the underlying developmental mechanisms remain unclear. Across different languages, a relationship between amplitude envelope sensitivity and phonological development has been found, suggesting that children may make use of amplitude modulation (AM) patterns within the envelope to develop a phonological system. Here we present the Spectral Amplitude Modulation Phase Hierarchy (S-AMPH) model, a set of algorithms for deriving the dominant AM patterns in child-directed speech (CDS). Using Principal Components Analysis, we show that rhythmic CDS contains an AM hierarchy comprising 3 core modulation timescales. These timescales correspond to key phonological units: prosodic stress (Stress AM, ~2 Hz), syllables (Syllable AM, ~5 Hz) and onset-rime units (Phoneme AM, ~20 Hz). We argue that these AM patterns could in principle be used by naïve listeners to compute acoustic-phonological mappings without lexical knowledge. We then demonstrate that the modulation statistics within this AM hierarchy indeed parse the speech signal into a primitive hierarchically-organised phonological system comprising stress feet (proto-words), syllables and onset-rime units. We apply the S-AMPH model to two other CDS corpora, one spontaneous and one deliberately-timed. The model accurately identified 72-82% (freely-read CDS) and 90-98% (rhythmically-regular CDS) stress patterns, syllables and onset-rime units. This in-principle demonstration that primitive phonology can be extracted from speech AMs is termed Acoustic-Emergent Phonology (AEP) theory. AEP theory provides a set of methods for examining how early phonological development is shaped by the temporal modulation structure of speech across languages. The S-AMPH model reveals a crucial developmental role for stress feet (AMs ~2 Hz). Stress feet underpin different linguistic rhythm typologies, and speech rhythm underpins language acquisition by infants in all languages.

Reducing nitrate loss in tile drainage water with cover crops and water-table management systems.

PubMed

Drury, C F; Tan, C S; Welacky, T W; Reynolds, W D; Zhang, T Q; Oloya, T O; McLaughlin, N B; Gaynor, J D

2014-03-01

Nitrate lost from agricultural soils is an economic cost to producers, an environmental concern when it enters rivers and lakes, and a health risk when it enters wells and aquifers used for drinking water. Planting a winter wheat cover crop (CC) and/or use of controlled tile drainage-subirrigation (CDS) may reduce losses of nitrate (NO) relative to no cover crop (NCC) and/or traditional unrestricted tile drainage (UTD). A 6-yr (1999-2005) corn-soybean study was conducted to determine the effectiveness of CC+CDS, CC+UTD, NCC+CDS, and NCC+UTD treatments for reducing NO loss. Flow volume and NO concentration in surface runoff and tile drainage were measured continuously, and CC reduced the 5-yr flow-weighted mean (FWM) NO concentration in tile drainage water by 21 to 38% and cumulative NO loss by 14 to 16% relative to NCC. Controlled tile drainage-subirrigation reduced FWM NO concentration by 15 to 33% and cumulative NO loss by 38 to 39% relative to UTD. When CC and CDS were combined, 5-yr cumulative FWM NO concentrations and loss in tile drainage were decreased by 47% (from 9.45 to 4.99 mg N L and from 102 to 53.6 kg N ha) relative to NCC+UTD. The reductions in runoff and concomitant increases in tile drainage under CC occurred primarily because of increases in near-surface soil hydraulic conductivity. Cover crops increased corn grain yields by 4 to 7% in 2004 increased 3-yr average soybean yields by 8 to 15%, whereas CDS did not affect corn or soybean yields over the 6 yr. The combined use of a cover crop and water-table management system was highly effective for reducing NO loss from cool, humid agricultural soils. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Transport characteristics and colossal dielectric response of cadmium sulfide nanoparticles

NASA Astrophysics Data System (ADS)

Ahmad, Mushtaq; Rafiq, M. A.; Hasan, M. M.

2013-10-01

We report here the synthesis of ˜20 nm sized cadmium sulfide (CdS) nanoparticles via conventional solid state reaction at low temperature ˜200 °C and ambient pressure. X-ray diffraction and high resolution transmission electron microscopy analysis confirmed the synthesis of hexagonal phased nanoparticles. Impedance and electrical modulus investigations were carried out in the frequency range 20 Hz to 2 MHz and at temperature from 300 K to 400 K, which show the presence of bulk, grain boundary, and sub-grain boundary phases in CdS nanoparticles. Overlapped large polaron tunneling was the observed mechanism of charge carriers in used temperature range. The presence of colossal dielectric constant in the system is attributed to the Maxwell-Wagner type polarization. High and temperature dependent dielectric constants make the CdS nanoparticles efficient material to be used in capacitive energy storage devices.

[Determination of protein by CdS quantum dot fluorometry].

PubMed

Hu, Wei-Ping; Jiao, Man; Dong, Xue-Zhi; Wang, Xin

2011-02-01

Determination of protein content by fluorometry was carried out. In this experiment, CdS quantum dots (QDs) that have special spectral properties were prepared with sodium hexametaphosphate as stabilizer and mercapto acetic acid as modifier by hydrothermal synthesis method. Based on the increase in fluorescence intensity after CdS reacted with bovine serum albumin (BSA), a new method for the determination of protein was established. Results show that the fluorescence intensity of system has a good linear relationship with the concentration of BSA in the range of 0.001 43-0.250 mg x mL(-1), and the linear equation was F = 5 444.301 03 + 43.327 39c, relation coefficient (r) was 0.996 6, the limit of detection was 0.001 4 mg x mL(-1). The method has been used for the determination of protein in milk and egg, and compared with the standard method (biuret method), and the results were satisfactory.

Cognitive dimensions of talim: evaluating weaving notation through cognitive dimensions (CDs) framework.

PubMed

Kaur, Gagan Deep

2017-05-01

The design process in Kashmiri carpet weaving is distributed over a number of actors and artifacts and is mediated by a weaving notation called talim. The script encodes entire design in practice-specific symbols. This encoded script is decoded and interpreted via design-specific conventions by weavers to weave the design embedded in it. The cognitive properties of this notational system are described in the paper employing cognitive dimensions (CDs) framework of Green (People and computers, Cambridge University Press, Cambridge, 1989) and Blackwell et al. (Cognitive technology: instruments of mind-CT 2001, LNAI 2117, Springer, Berlin, 2001). After introduction to the practice, the design process is described in 'The design process' section which includes coding and decoding of talim. In 'Cognitive dimensions of talim' section, after briefly discussing CDs framework, the specific cognitive dimensions possessed by talim are described in detail.

Impact of the Cornea Donor Study (CDS) on Acceptance of Corneas from Older Donors

PubMed Central

Sugar, Alan; Montoya, Monty M.; Beck, Roy; Cowden, John W.; Dontchev, Mariya; Gal, Robin L.; Kollman, Craig; Malling, Jackie; Mannis, Mark J.; Tennant, Bradley

2014-01-01

Purpose Evaluate retrospectively whether findings from the Cornea Donor Study (CDS) led to changes in the transplantation of corneas from older donors. Methods United States eye banks provided complete data on donor age and placement (domestic or international) for 86,273 corneas from 1998 to 2009. The data were analyzed by 3 time periods: preceding CDS (1998–1999), during CDS (2000–2007) and after publication of CDS 5 year results (2008–2009), and separately for corneas placed within vs. outside the United States. Results For corneal tissues transplanted in the United States, the percentage of donors ≥66 years old increased from 19% before CDS to 21% during CDS and 25% after CDS (p<0.001). Corresponding median (25th-75th percentile) donor ages were 53 (39–63), 54 (41–64) and 57 (46–66), respectively (p<0.001). The opposite trend was observed for corneas distributed outside the United States with the percentage of donors ≥66 years old decreasing from 56% to 42% to 34%, respectively. Donor age trends over time varied by eye bank. Conclusions There was a modest overall increase in the donor age of corneas transplanted in the United States from 1998 to 2009, but the retrospective nature of the study limits our ability to attribute this change to the CDS. The modest increases in the donor age of corneas transplanted is a positive finding, but wider acceptance of older corneal donor tissue should be encouraged based on the five-year evidence generated by the CDS. PMID:22262218

Biological and catalytic applications of green synthesized fluorescent N-doped carbon dots using Hylocereus undatus.

PubMed

Arul, Velusamy; Edison, Thomas Nesakumar Jebakumar Immanuel; Lee, Yong Rok; Sethuraman, Mathur Gopalakrishnan

2017-03-01

In this work, a simple hydrothermal route for the synthesis of fluorescent nitrogen doped carbon dots (N-CDs) is reported. The Hylocereus undatus (H. undatus) extract and aqueous ammonia are used as carbon and nitrogen source, respectively. The optical properties of synthesized N-CDs are analyzed using UV-Visible (UV-Vis) and fluorescence spectroscopy. The surface morphology, elemental composition, crystallinity and functional groups present in the N-CDs are examined using high resolution transmission electron microscopy (HR-TEM) with energy dispersive spectroscopy (EDS), selected area electron diffraction (SAED), X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy, respectively. The synthesized N-CDs emit strong blue fluorescence at 400nm under the excitation of 320nm. Further, the excitation dependent emission properties are also observed from the fluorescence of synthesized N-CDs. The HR-TEM results reveal that synthesized N-CDs are in spherical shape with average diameter of 2.5nm. The XRD pattern exhibits, the graphitic nature of synthesized N-CDs. The doping of nitrogen is confirmed from the EDS and FT-IR studies. The cytotoxicity and biocompatibility of N-CDs are evaluated through MTT assay on L-929 (Lymphoblastoid-929) and MCF-7 (Michigan Cancer Foundation-7) cells. The results indicate that the fluorescent N-CDs show less cytotoxicity and good biocompatibility on both L-929 and MCF-7 cells. Moreover, the N-CDs show excellent catalytic activity towards the reduction of methylene blue by sodium borohydride. Copyright © 2017 Elsevier B.V. All rights reserved.

Simple and green synthesis of protein-conjugated CdS nanoparticles and spectroscopic study on the interaction between CdS and zein

NASA Astrophysics Data System (ADS)

Qin, Dezhi; Zhang, Li; Du, Xian; Wang, Yabo; Zhang, Qiuxia

2016-09-01

The present study demonstrates the role of zein molecules in synthesizing CdS nanoassemblies through protein-directed, green synthetic approach. Zein molecules can as capping ligand and stabilizing agent to regulate the nucleation and growth of CdS nanocrystals, and the obtained products are organic-inorganic nanocomposites. The analysis of surface charge and conductivity indicates that strong electrostatic force restricts mobility of ions, which creates a local supersaturation surrounding the binding sites of zein and reduces the activated energy of nucleation. The interaction between Cd2+/CdS and zein molecules was systematically investigated through spectroscopy techniques. Fourier transform infrared (FT-IR) spectra were used to envisage the binding of the functional groups of zein with the surface of CdS nanoparticles. Ultraviolet visible (UV-Vis) and photoluminescence (PL) spectra results show that Cd2+/CdS might interact with the aromatic amino acids of protein molecules and change its chemical microenvironment. The quantum-confined effect of nanocrystals is confirmed by optical absorption spectrum due to the small size (3-5 nm) of CdS particles. The data of circular dichroism (CD) spectra indicate that the formation of CdS nanocrystals could lead to the conformational change of zein molecules. Moreover, the possible mechanism of CdS nanocrystals growth in zein solution was also discussed. The weak interactions such as Van der Waals, hydrophobic forces and hydrogen bonds in zein molecules should play a crucial factor in the self-assembly of small nanoparticles.

A new information architecture, website and services for the CMS experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, Lucas; Rusack, Eleanor; Zemleris, Vidmantas

2012-01-01

The age and size of the CMS collaboration at the LHC means it now has many hundreds of inhomogeneous web sites and services, and hundreds of thousands of documents. We describe a major initiative to create a single coherent CMS internal and public web site. This uses the Drupal web Content Management System (now supported by CERN/IT) on top of a standard LAMP stack (Linux, Apache, MySQL, and php/perl). The new navigation, content and search services are coherently integrated with numerous existing CERN services (CDS, EDMS, Indico, phonebook, Twiki) as well as many CMS internal Web services. We describe themore » information architecture, the system design, implementation and monitoring, the document and content database, security aspects, and our deployment strategy, which ensured continual smooth operation of all systems at all times.« less

A new Information Architecture, Website and Services for the CMS Experiment

NASA Astrophysics Data System (ADS)

Taylor, Lucas; Rusack, Eleanor; Zemleris, Vidmantas

2012-12-01

The age and size of the CMS collaboration at the LHC means it now has many hundreds of inhomogeneous web sites and services, and hundreds of thousands of documents. We describe a major initiative to create a single coherent CMS internal and public web site. This uses the Drupal web Content Management System (now supported by CERN/IT) on top of a standard LAMP stack (Linux, Apache, MySQL, and php/perl). The new navigation, content and search services are coherently integrated with numerous existing CERN services (CDS, EDMS, Indico, phonebook, Twiki) as well as many CMS internal Web services. We describe the information architecture; the system design, implementation and monitoring; the document and content database; security aspects; and our deployment strategy, which ensured continual smooth operation of all systems at all times.

Facile and eco-friendly synthesis of green fluorescent carbon nanodots for applications in bioimaging, patterning and staining.

PubMed

Shi, Lihong; Li, Yanyan; Li, Xiaofeng; Wen, Xiangping; Zhang, Guomei; Yang, Jun; Dong, Chuan; Shuang, Shaomin

2015-04-28

We report a facile and eco-friendly strategy for the fabrication of green fluorescent carbon nanodots (CDs), and demonstrate their applications for bio-imaging, patterning, and staining. A one-pot hydrothermal method using various plant petals yields bright green-emitting CDs, providing an easy way for the production of green fluorescent CDs without the need for a tedious synthetic methodology or the use of toxic/expensive solvents and starting materials. The as-prepared CDs show small size distribution and excellent dispersibility. Their strong green fluorescence is observed when the excitation wavelength is between 430 nm and 490 nm. Moreover, they exhibit high tolerance to various external conditions, such as pH values, external cations, and continuous excitation. Due to minimum toxicity as well as good photoluminescence properties, these CDs can be applied to in vitro and in vivo imaging, patterning, and staining. According to confocal fluorescence imaging of human uterine cervical squamous cell carcinoma cells, CDs penetrate into the cell and enter the cytoplasm and the nucleus. More strikingly, carp is directly fed with CDs for in vivo imaging and shows bright green fluorescence at an excitation wavelength of 470 nm. In addition, the obtained CDs are used as fluorescent inks for drawing luminescence patterns. Finally, we also apply the CDs as a fluorescent dye. Interestingly, the absorbent filter paper with staining emits dramatic fluorescence under 470 nm excitation.

Rapid solid-phase microwave synthesis of highly photoluminescent nitrogen-doped carbon dots for Fe3+ detection and cellular bioimaging

NASA Astrophysics Data System (ADS)

He, Guili; Xu, Minghan; Shu, Mengjun; Li, Xiaolin; Yang, Zhi; Zhang, Liling; Su, Yanjie; Hu, Nantao; Zhang, Yafei

2016-09-01

Recently, carbon dots (CDs) have been playing an increasingly important role in industrial production and biomedical field because of their excellent properties. As such, finding an efficient method to quickly synthesize a large scale of relatively high purity CDs is of great interest. Herein, a facile and novel microwave method has been applied to prepare nitrogen doped CDs (N-doped CDs) within 8 min using L-glutamic acid as the sole reaction precursor in the solid phase condition. The as-prepared N-doped CDs with an average size of 1.64 nm are well dispersed in aqueous solution. The photoluminescence of N-doped CDs is pH-sensitive and excitation-dependent. The N-doped CDs show a strong blue fluorescence with relatively high fluorescent quantum yield of 41.2%, which remains stable even under high ionic strength. Since the surface is rich in oxygen-containing functional groups, N-doped CDs can be applied to selectively detect Fe3+ with the limit of detection of 10-5 M. In addition, they are also used for cellular bioimaging because of their high fluorescent intensity and nearly zero cytotoxicity. The solid-phase microwave method seems to be an effective strategy to rapidly obtain high quality N-doped CDs and expands their applications in ion detection and cellular bioimaging.

Facile green synthesis of fluorescent N-doped carbon dots from Actinidia deliciosa and their catalytic activity and cytotoxicity applications

NASA Astrophysics Data System (ADS)

Arul, Velusamy; Sethuraman, Mathur Gopalakrishnan

2018-04-01

Green synthesis of fluorescent nitrogen doped carbon dots (N-CDs) using Actinidia deliciosa (A. deliciosa) fruit extract as a carbon precursor and aqueous ammonia as a nitrogen dopant is reported here. The synthesized N-CDs were characterized by high resolution transmission electron microscopy (HR-TEM), energy dispersive spectroscopy (EDS), selected area electron diffraction (SAED), UV-Visible spectroscopy (UV-Vis), fluorescence spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The average size of the N-CDs was approximately 3.59 nm and the calculated inter layer distance was found to be 0.21 nm. Raman spectroscopy and SAED pattern revealed the graphitic nature of the synthesized N-CDs. The N-CDs were found to emit intense blue color at 405 nm under the excitation of 315 nm. The doping of nitrogen over the surface of the N-CDs was confirmed by EDS, FT-IR and XPS studies. The synthesized N-CDs were found to exhibit excellent catalytic activity in the reduction of Rhodamine-B using sodium borohydrate. The MTT assay was used to evaluate the cytotoxicity and biocompatibility of N-CDs towards L-929 and MCF-7 cells. From the results obtained, it was found that the N-CDs exhibit low cytotoxicity and superior biocompatibility on both L-929 and MCF-7 cells.

Development of CdS Nanostructures by Thermal Decomposition of Aminocaproic Acid-Mixed Cd-Thiourea Complex Precursor: Structural, Optical and Photocatalytic Characterization.

PubMed

Patel, Jayesh D; Mighri, Frej; Ajji, Abdellah; Chaudhuri, Tapas K

2015-04-01

The present work deals with two different CdS nanostructures produced via hydrothermal and solvothermal decompositions of aminocaproic acid (ACA)-mixed Cd-thiourea complex precursor at 175 °C. Both nanostructures were extensively characterized for their structural, morphological and optical properties. The powder X-ray diffraction characterization showed that the two CdS nanostructures present a wurtzite morphology. Scanning electron microscopy and energy-dispersive X-ray characterizations revealed that the hydrothermal decomposition produced well-shaped CdS flowers composed of six dendritic petals, and the solvothermal decomposition produced CdS microspheres with close stoichiometric chemical composition. The UV-vis absorption and photoluminescence spectra of CdS dendritic flowers and microsphere nanostructures showed that both nanostructures present a broad absorption between 200 and 700 nm and exhibit strong green emissions at 576 and 520 nm upon excitations at 290 nm and 260 nm, respectively. The transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) characterizations confirmed that CdS microspheres were mesoporous and were composed of small nanocrystals. A possible growth mechanism in the formation of the CdS nanostructures was proposed based on morphology evolution as a function of the reaction time. Furthermore, the as-synthesized CdS nanostructures were found to exhibit highly efficient photocatalytic activities for the degradation of methyl orange (MeO) and rhodamine B (RhB) dyes.

The excitonic photoluminescence mechanism and lasing action in band-gap-tunable CdS(1-x)Se(x) nanostructures.

PubMed

Dai, Jun; Zhou, Pengxia; Lu, Junfeng; Zheng, Hongge; Guo, Jiyuan; Wang, Fang; Gu, Ning; Xu, Chunxiang

2016-01-14

Bandgap tunable semiconductor materials have wide application in integrated-optoelectronic and communication devices. The CdS1-xSex ternary semiconductor materials covering green-red bands have been reported previously, but their basic band-gap and optical properties crucial to the performance of the CdS1-xSex-based optoelectronic devices have not been deeply understood. In this paper, we theoretically simulated and discussed the feasibility of bandgap-tunable CdS1-xSex nanomaterials for designing wavelength tunable microlasers. Then we fabricated the CdS1-xSex nanobelts with their band gap ranging from 2.4 to 1.74 eV by adjusting the composition ratio x in the vapor-phase-transport growth process. The temperature-dependent photoluminescence and exciton-related optical constants of the CdS1-xSex nanobelts were carefully demonstrated. Finally, the wavelength-tunable Fabry-Perot lasing in CdS1-xSex nanobelts was obtained, and the Fabry-Perot lasing mechanism was numerically simulated by the FDTD method. The systematic results on the mechanism of the tunable band gap, exciton properties and lasing of the CdS1-xSex nanostructure help us deeply understand the intrinsic optical properties of this material, and will build a strong foundation for future application of green-red wavelength-tunable CdS1-xSex microlasers.

75 FR 11589 - Order Extending Temporary Exemptions Under the Securities Exchange Act of 1934 in Connection with...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-11

... make payments under a CDS contract is triggered by a default or other credit event as to such entity or... CDS clearing by ICE Trust. We recognize, however, that there could be legal uncertainty in the event..., and the access to clearing services by independent CDS exchanges or CDS trading platforms.\\15\\ \\15...

Facile synthesis of S, N co-doped carbon dots and investigation of their photoluminescence properties.

PubMed

Zhang, Yue; He, Junhui

2015-08-21

A facile one-pot approach to prepare photoluminescent carbon dots (CDs) was developed through hydrothermal treatment of cysteine and citric acid. The obtained CDs show stable and bright blue emission with a quantum yield of 54% and an average lifetime of 11.61 ns. Moreover, the two-photon induced upconversion fluorescence of the CDs was observed and demonstrated. Interestingly, both down and up conversion fluorescence of the CDs show excitation-independent emission, which is quite different from most of the previously reported CDs. Ultrafast spectroscopy was also employed here to study the photoluminescence (PL) properties of the CDs. After characterization using various spectroscopic techniques, a unique PL mechanism for the as-prepared CDs' fluorescence was proposed accordingly. In addition, the influence of various metal ions on the CD fluorescence was examined and no quenching phenomena were observed. Meanwhile, gold nanoparticles (Au NPs) were found to be good quenchers of CD fluorescence and their quenching behavior was fitted to the Stern-Volmer equation. This provides new opportunities for fluorescence sensor designs and light energy conversion applications. Finally, the as-prepared CDs were inkjet-printed to form a desirable pattern, which is useful for fluorescent patterns, and anti-counterfeiting labeling.

A Comparative Analysis of Phase-Change Wastewater Processing Approaches for Microgravity

NASA Technical Reports Server (NTRS)

Lange, Kevin

2016-01-01

Two phase-change wastewater processing candidates, the ISS Vapor Compression Distillation (VCD) System and the Cascade Distiller System (CDS), are compared based on dynamic modeling of both technologies. Differences in fluid handling and energy recovery for the technologies are described and contrasted. Model predictions are presented showing how temperatures, pressures, and compositions vary locally within each distiller. These dynamic variations are difficult to observe experimentally and have implications regarding non-condensable buildup and salt precipitation potential. Alternative architectures involving VCD and CDS components are analyzed in terms of predicted performance and equivalent system mass (ESM). The addition of a downstream brine processor to increase water recovery is also evaluated. Options for reducing overall ESM are discussed, including the possibility of developing a single precipitation-tolerant primary wastewater processor.

Fluorescent chemosensor for pyridine based on N-doped carbon dots.

PubMed

Campos, B B; Abellán, C; Zougagh, M; Jimenez-Jimenez, J; Rodríguez-Castellón, E; Esteves da Silva, J C G; Ríos, A; Algarra, M

2015-11-15

Fluorescent carbon dots (CDs) and its nitrogen doped (N-CDs) nanoparticles have been synthesized from lactose as precursor using a bottom-up hydrothermal methodology. The synthesized nanoparticles have been characterized by elemental analysis, FTIR, Raman, TEM, DLS, XPS, and steady-state and life-time fluorescence. The synthesized carbon nanoparticles, CDs and N-CDs, have a size at about 7.7±2.4 and 50±15nm, respectively, and quantum yields of 8% (CDs) and 11% (N-CDs). These techniques demonstrated the effectiveness of the synthesis procedure and the functionalization of the CDs surface with amine and amide groups in the presence of NH3 in aqueous media. The effect of excitation wavelength and pH on the luminescent properties was studied. Under the optimal conditions, the nitrogen doped nanoparticles can be used as pyridine sensor in aqueous media because they show an enhancement of its fluorescence with a good linear relationship. The analytical method is simple, reproducible and very sensitive for pyridine determination. Copyright © 2015 Elsevier Inc. All rights reserved.

Enhanced photo response of mesoporous nanostructured CdS thin film via electrospray aerosol deposition technique

NASA Astrophysics Data System (ADS)

Logu, T.; Soundarrajan, P.; Sankarasubramanian, K.; Sethuraman, K.

2018-04-01

In this work, a high crystalline and mesoporous nanostructured cadmium sulfide (CdS) thin film was successfully grown on the FTO substrates using facile Electrospray Aerosol Deposition (ESAD) technique. The structural, optical, morphological and electrical properties of CdS thin film have been systematically examined. CdS thin film exhibits the hexagonal wurtzite crystal structure with polycrystalline nature. The optical band gap energy of the prepared film was estimated from the Tauc plot and is 2.43 eV. The SEM and AFM images show that the well-interconnected CdS nanoparticles gives mesoporous like morphology. The fine aerosol generated from the ESAD process induces the alteration in the surface morphological structure of deposited CdS film that consequences in enhanced electrical and photo-physical properties. The photoconductivity of the sample has been studied which demonstrates significant photo current. The present study predicts that mesoporous nanostructured CdS thin film would be given a special interest for optoelectronic applications.

Arrays of Ultrathin CdS Nanoflakes with High-Energy Surface for Efficient Gas Detection.

PubMed

Liu, Xiao-Hua; Yin, Peng-Fei; Kulinich, Sergei A; Zhou, Yu-Zhu; Mao, Jing; Ling, Tao; Du, Xi-Wen

2017-01-11

It is fascinating and challenging to endow conventional materials with unprecedented properties. For instance, cadmium sulfide (CdS) is an important semiconductor with excellent light response; however, its potential in gas-sensing was underestimated owing to relatively low chemical activity and poor electrical conductivity. Herein, we demonstrate that an ideal architecture, ultrathin nanoflake arrays (NFAs), can improve significantly gas-sensing properties of CdS material. The CdS NFAs are grown directly on the interdigitated electrode to expose large surface area. Their thickness is reduced below the double Debye length of CdS, permitting to achieve a full depletion of carriers. Particularly, the prepared CdS nanoflakes are enclosed with high-energy {0001} facets exposed, which provides more active sites for gas adsorption. Moreover, the NFAs exhibit the light-trapping effect, which further enhances their gas sensitivity. As a result, the as-prepared CdS NFAs demonstrate excellent gas-sensing and light-response properties, thus being capable of dual gas and light detection.

Two Closely Related Genes of Arabidopsis Encode Plastidial Cytidinediphosphate Diacylglycerol Synthases Essential for Photoautotrophic Growth1[C

PubMed Central

Haselier, André; Akbari, Hana; Weth, Agnes; Baumgartner, Werner; Frentzen, Margrit

2010-01-01

Cytidinediphosphate diacylglycerol synthase (CDS) catalyzes the formation of cytidinediphosphate diacylglycerol, an essential precursor of anionic phosphoglycerolipids like phosphatidylglycerol or -inositol. In plant cells, CDS isozymes are located in plastids, mitochondria, and microsomes. Here, we show that these isozymes are encoded by five genes in Arabidopsis (Arabidopsis thaliana). Alternative translation initiation or alternative splicing of CDS2 and CDS4 transcripts can result in up to 10 isoforms. Most of the cDNAs encoding the various plant isoforms were functionally expressed in yeast and rescued the nonviable phenotype of the mutant strain lacking CDS activity. The closely related genes CDS4 and CDS5 were found to encode plastidial isozymes with similar catalytic properties. Inactivation of both genes was required to obtain Arabidopsis mutant lines with a visible phenotype, suggesting that the genes have redundant functions. Analysis of these Arabidopsis mutants provided further independent evidence for the importance of plastidial phosphatidylglycerol for structure and function of thylakoid membranes and, hence, for photoautotrophic growth. PMID:20442275

CeO₂ Enhanced Ethanol Sensing Performance in a CdS Gas Sensor.

PubMed

Li, Meishan; Ren, Wei; Wu, Rong; Zhang, Min

2017-07-05

CdS nanowires (NWs) were fabricated through a facile low-temperature solvothermal method, following which CeO₂ nanoparticles were modified on the NWs. The ethanol sensing characteristics of pure CdS and decorated ones with different CeO₂ content were studied. It was found that the sensing performance of CdS was significantly improved after CeO₂ decoration. In particular, the 5 at% CeO₂/CdS composite exhibited a much higher response to 100 ppm ethanol (about 52), which was 2.6 times larger than that of pure CdS. A fast response and recovery time (less than 12 s and 3 s, respectively) were obtained as well as an excellent selectivity. These results make the CeO₂-decorated CdS NWs good candidates for ethanol sensing applications.

Quick synthesis of 2-propanol derived fluorescent carbon dots for bioimaging applications

NASA Astrophysics Data System (ADS)

Angamuthu, Raja; Palanisamy, Priya; Vasudevan, Vasanthakumar; Nagarajan, Sedhu; Rajendran, Ramesh; Vairamuthu, Raj

2018-04-01

Herein, for the first time, we present a one-pot ingenious preparative method for fluorescent carbon dots from 2-propanol (2P-CDs) without external treatments. Structure, morphology, chemical composition and fluorescence properties of the 2P-CDs were examined. These results confirm that the as-synthesized 2P-CDs are amorphous, monodispersed, spherical and the average particle size is 2.5 ± 0.7 nm. Most importantly, excitation-dependent emission properties were observed, which suggest that these 2P-CDs may be used in multicolor bioimaging applications. When incubated with HeLa cells, the 2P-CDs exhibit low cytotoxicity, and positive biocompatibility. Confocal microscopy image shows the uptake of 2P-CDs by HeLa cells and the application of probable biomarker is demonstrated.

Optical characterization of CdS nanorods capped with starch

NASA Astrophysics Data System (ADS)

Roy, J. S.; Pal Majumder, T.; Schick, C.

2015-05-01

Well crystalline uniform CdS nanorods were grown by changing the concentration of maize starch. The highly polymeric (branched) structure of starch enhances the growth of CdS nanorods. The average diameter of the nanorods is 20-25 nm while length is of 500-600 nm as verified from SEM and XRD observations. The optical band gaps of the CdS nanorods are varying from 2.66 eV to 2.52 eV depending on concentration of maize starch. The photoluminescence (PL) emission bands are shifted from 526 nm to 529 nm with concentration of maize starch. We have also observed the enhanced PL intensity in CdS nanorods capped with starch. The Fourier transform infrared (FTIR) spectroscopy shows the significant effect of starch on CdS nanorods.

Wavelength tunable single nanowire lasers based on surface plasmon polariton enhanced Burstein-Moss effect.

PubMed

Liu, Xinfeng; Zhang, Qing; Yip, Jing Ngei; Xiong, Qihua; Sum, Tze Chien

2013-01-01

Wavelength tunable semiconductor nanowire (NW) lasers are promising for multifunctional applications ranging from optical communication to spectroscopy analysis. Here, we present a demonstration of utilizing the surface plasmon polariton (SPP) enhanced Burstein-Moss (BM) effect to tune the lasing wavelength of a single semiconductor NW. The photonic lasing mode of the CdS NW (with length ~10 μm and diameter ~220 nm) significantly blue shifts from 504 to 483 nm at room temperature when the NW is in close proximity to the Au film. Systematic steady state power dependent photoluminescence (PL) and time-resolved PL studies validate that the BM effect in the hybrid CdS NW devices is greatly enhanced as a consequence of the strong coupling between the SPP and CdS excitons. With decreasing dielectric layer thickness h from 100 to 5 nm, the enhancement of the BM effect becomes stronger, leading to a larger blue shift of the lasing wavelength. Measurements of enhanced exciton emission intensities and recombination rates in the presence of Au film further support the strong interaction between SPP and excitons, which is consistent with the simulation results.

Child Development Services: Army Regulation 608-10 (Effective 15 October 1983).

ERIC Educational Resources Information Center

Department of the Army, Washington, DC.

As of October 15, 1983, Army Regulation 608-10 has prescribed policies, procedures, and standards for establishing and operating Child Development Services (CDS), formerly Child Support Services, at Army installations. The regulation applies to all activities, contractors, individuals, and private organizations providing child care services for…

Green Synthesis of Bifunctional Fluorescent Carbon Dots from Garlic for Cellular Imaging and Free Radical Scavenging.

PubMed

Zhao, Shaojing; Lan, Minhuan; Zhu, Xiaoyue; Xue, Hongtao; Ng, Tsz-Wai; Meng, Xiangmin; Lee, Chun-Sing; Wang, Pengfei; Zhang, Wenjun

2015-08-12

Nitrogen and sulfur codoped carbon dots (CDs) were prepared from garlic by a hydrothermal method. The as-prepared CDs possess good water dispersibility, strong blue fluorescence emission with a fluorescent quantum yield of 17.5%, and excellent photo and pH stabilities. It is also demonstrated that the fluorescence of CDs are resistant to the interference of metal ions, biomolecules, and high ionic strength environments. Combining with low cytotoxicity properties, CDs could be used as an excellent fluorescent probe for cellular multicolor imaging. Moreover, the CDs were also demonstrated to exhibit favorable radical scavenging activity.

Synthesis and formation mechanistic investigation of nitrogen-doped carbon dots with high quantum yields and yellowish-green fluorescence

NASA Astrophysics Data System (ADS)

Hou, Juan; Wang, Wei; Zhou, Tianyu; Wang, Bo; Li, Huiyu; Ding, Lan

2016-05-01

Heteroatom doped carbon dots (CDs) have received increasing attention due to their unique properties and related applications. However, previously reported CDs generally show strong emission only in the blue-light region, thus restricting their further applications. And the fundamental investigation on the preparation process is always neglected. Herein, we have developed a simple and solvent-free synthetic strategy to fabricate nitrogen-doped CDs (N-CDs) from citric acid and dicyandiamide. The as-prepared N-CDs exhibited a uniform size distribution, strong yellowish-green fluorescence emission and a high quantum yield of 73.2%. The products obtained at different formation stages were detailedly characterized by transmission electron microscopy, X-ray diffraction spectrometer, X-ray photoelectron spectroscopy and UV absorbance spectroscopy. A possible formation mechanism has thus been proposed including dehydration, polymerization and carbonization. Furthermore, the N-CDs could serve as a facile and label-free probe for the detection of iron and fluorine ions with detection limits of 50 nmol L-1 and 75 nmol L-1, respectively.Heteroatom doped carbon dots (CDs) have received increasing attention due to their unique properties and related applications. However, previously reported CDs generally show strong emission only in the blue-light region, thus restricting their further applications. And the fundamental investigation on the preparation process is always neglected. Herein, we have developed a simple and solvent-free synthetic strategy to fabricate nitrogen-doped CDs (N-CDs) from citric acid and dicyandiamide. The as-prepared N-CDs exhibited a uniform size distribution, strong yellowish-green fluorescence emission and a high quantum yield of 73.2%. The products obtained at different formation stages were detailedly characterized by transmission electron microscopy, X-ray diffraction spectrometer, X-ray photoelectron spectroscopy and UV absorbance spectroscopy. A possible formation mechanism has thus been proposed including dehydration, polymerization and carbonization. Furthermore, the N-CDs could serve as a facile and label-free probe for the detection of iron and fluorine ions with detection limits of 50 nmol L-1 and 75 nmol L-1, respectively. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr02701f

Annealing effects on the chemical deposited CdS films and the electrical properties of CdS/CdTe solar cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, Junfeng; Institute of Materials Science, Darmstadt University of Technology, Petersenstr. 23, 64287 Darmstadt; Liao, Cheng, E-mail: Cliao@pku.edu.cn

2011-02-15

Graphical abstract: From XPS core level spectras, compared with as-depositing CdS (sample A), the Fermi level is shifting closer to the conduction band after annealing treatment in the oxygen (sample B) while it is shifting closer to the valence band after annealing treatment in the argon-hydrogen (sample C). That might be the main reason of the different performance of the final devices. The open circuit voltage of the CdS/CdTe solar cell increases when the CBD CdS is annealed with oxygen, while the performance of the solar cell decreases when the CBD CdS is annealed with argon-hydrogen. Research highlights: {yields} Twomore » different methods (oxidation and reduction) were used to anneal CdS films for CdTe solar cells. {yields} Electrical properties were analyzed by XPS (Fermi levels of CdS films). {yields} Annealing treatment in oxidation atmosphere could shift Fermi level of CdS film to higher position and consequently improve the CdS/CdTe junction and performance of solar cells. -- Abstract: CdS layers grown by chemical bath deposition (CBD) are annealed in the oxygen and argon-hydrogen atmosphere respectively. It has been found that the open circuit voltage of the CdS/CdTe solar cell increases when the CBD CdS is annealed with oxygen before the deposition of CdTe by close spaced sublimation (CSS), while the performance of the solar cell decreases when the CBD CdS is annealed with argon-hydrogen. Electronic properties of the CdS films are investigated using X-ray photo-electron spectroscopy (XPS), which indicates that the Fermi level is shifting closer to the conduction band after annealing in the oxygen and consequently a higher open circuit voltage of the solar cell can be obtained.« less

Nanoniobia modification of CdS photoanode for an efficient and stable photoelectrochemical cell.

PubMed

Pareek, Alka; Paik, Pradip; Borse, Pramod H

2014-12-30

Herein we report the surface modification of a CdS film by niobia nanoparticles via thioglycerol as an organic linker and thus fabricate an efficient and a stable photoanode for a photoelectrochemical (PEC) cell. We have synthesized three differenly sized (∼3, ∼6 ,and ∼9 nm) niobia nanoparticles by a hydrothermal synthesis approach and have further investigated the particle-size-dependent PEC performance of the nanoparticle-modified CdS photoanode. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) confirm the formation of Nb2O5 nanoparticles that are prepared via decomposition of the niobium peroxo complex during the hydrothermal reaction and reveal the presence of surface OH(-) groups over niobia nanoparticles that impart a high catalytic property to a material. The nano-Nb2O5-modified photoanode displayed a 23-fold higher power conversion efficiency compared to that of CdS. This modified structure increases the open circuit voltage (OCV) from 0.65 to 0.77 V, which is attributed to the nano-Nb2O5-induced surface passivation effect over bare CdS. Linking of nanoparticles on the CdS surface improves the photocorrosion stability of the CdS photoanode for even longer than 4 h in contrast to the tens of minutes for the base CdS surface. The uniform coverage of the CdS photoanode surface by niobia nanoparticles is thus found to be the controlling parameter for achieving a higher PEC performance and stability of the photoanode. This finding directed us to design an improved CdS photoanode for efficient and prolonged PEC hydrogen generation from a PEC cell.

Recombinant yeast as a functional tool for understanding bitterness and cucurbitacin biosynthesis in watermelon (Citrullus spp.).

PubMed

Davidovich-Rikanati, Rachel; Shalev, Lior; Baranes, Nadine; Meir, Ayala; Itkin, Maxim; Cohen, Shahar; Zimbler, Kobi; Portnoy, Vitaly; Ebizuka, Yutaka; Shibuya, Masaaki; Burger, Yosef; Katzir, Nurit; Schaffer, Arthur A; Lewinsohn, Efraim; Tadmor, Ya'akov

2015-01-01

Cucurbitacins are a group of bitter-tasting oxygenated tetracyclic triterpenes that are produced in the family Cucurbitaceae and other plant families. The natural roles of cucurbitacins in plants are probably related to defence against pathogens and pests. Cucurbitadienol, a triterpene synthesized from oxidosqualene, is the first committed precursor to cucurbitacins produced by a specialized oxidosqualene cyclase termed cucurbitadienol synthase. We explored cucurbitacin accumulation in watermelon in relation to bitterness. Our findings show that cucurbitacins are accumulated in bitter-tasting watermelon, Citrullus lanatus var. citroides, as well as in their wild ancestor, C. colocynthis, but not in non-bitter commercial cultivars of sweet watermelon (C. lanatus var. lanatus). Molecular analysis of genes expressed in the roots of several watermelon accessions led to the isolation of three sequences (CcCDS1, CcCDS2 and ClCDS1), all displaying high similarity to the pumpkin CpCPQ, encoding a protein previously shown to possess cucurbitadienol synthase activity. We utilized the Saccharomyces cerevisiae strain BY4743, heterozygous for lanosterol synthase, to probe for possible encoded cucurbitadienol synthase activity of the expressed watermelon sequences. Functional expression of the two sequences isolated from C. colocynthis (CcCDS1 and CcCDS2) in yeast revealed that only CcCDS2 possessed cucurbitadienol synthase activity, while CcCDS1 did not display cucurbitadienol synthase activity in recombinant yeast. ClCDS1 isolated from C. lanatus var. lanatus is almost identical to CcCDS1. Our results imply that CcCDS2 plays a role in imparting bitterness to watermelon. Yeast has been an excellent diagnostic tool to determine the first committed step of cucurbitacin biosynthesis in watermelon. Copyright © 2014 John Wiley & Sons, Ltd.

Antimanic-like activity of candesartan in mice: Possible involvement of antioxidant, anti-inflammatory and neurotrophic mechanisms.

PubMed

de Souza Gomes, Júlia Ariana; de Souza, Greicy Coelho; Berk, Michael; Cavalcante, Lígia Menezes; de Sousa, Francisca Cléa F; Budni, Josiane; de Lucena, David Freitas; Quevedo, João; Carvalho, André F; Macêdo, Danielle

2015-11-01

Activation of the brain angiotensin II type 1 receptor (AT1R) triggers pro-oxidant and pro-inflammatory mechanisms which are involved in the neurobiology of bipolar disorder (BD). Candesartan (CDS) is an AT1 receptor antagonist with potential neuroprotective properties. Herein we investigated CDS effects against oxidative, neurotrophic inflammatory and cognitive effects of amphetamine (AMPH)-induced mania. In the reversal protocol adult mice were given AMPH 2 mg/kg i.p. or saline and between days 8 and 14 received CDS 0.1, 0.3 or 1 mg/kg orally, lithium (Li) 47.5 mg/kg i.p., or saline. In the prevention treatment, mice were pretreated with CDS, Li or saline prior to AMPH. Locomotor activity and working memory performance were assessed. Glutathione (GSH), thiobarbituric acid-reactive substance (TBARS) and TNF-α levels were evaluated in the hippocampus (HC) and cerebellar vermis (CV). Brain-derived neurotrophic factor (BDNF) and glycogen synthase kinase 3-beta (GSK-3beta) levels were measured in the HC. CDS and Li prevented and reversed the AMPH-induced increases in locomotor activity. Only CDS prevented and reversed AMPH-induced working memory deficits. CDS prevented AMPH-induced alterations in GSH (HC and CV), TBARS (HC and CV), TNF-α (HC and CV) and BDNF (HC) levels. Li prevented alterations in BDNF and phospho-Ser9-GSK3beta. CDS reversed AMPH-induced alterations in GSH (HC and CV), TBARS (HC), TNF-α (CV) and BDNF levels. Li reversed AMPH-induced alterations in TNF-α (HC and CV) and BDNF (HC) levels. CDS is effective in reversing and preventing AMPH-induced behavioral and biochemical alterations, providing a rationale for the design of clinical trials investigating CDS׳s possible therapeutic effects. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.

Structural and Optical Properties of Core-Shell TiO2/CdS Prepared by Chemical Bath Deposition

NASA Astrophysics Data System (ADS)

Al-Jawad, Selma M. H.

2017-10-01

Titanium dioxide (TiO2) nanorod arrays (NRAs) sensitized with cadmium sulfide (CdS) nanoparticles (NPs) were deposited by chemical bath deposition (CBD). TiO2 NRAs were also obtained by using the same method on glass substrates coated with fluorine-doped tin oxide (FTO). The structure of the FTO/TiO2/CdS core-shell was characterized by x-ray diffraction (XRD), atomic force microscopy, scanning electron microscopy, ultraviolet-visible (UV-Vis) absorption spectroscopy, photoluminescence, and photoelectrocatalysis of FTO/TiO2 and FTO/TiO2/CdS. The FTO/TiO2 conformed to anatase and rutile phase structures for different pH values and also with annealing. XRD patterns of the FTO/TiO2/CdS sample exhibited two peaks corresponding to hexagonal (100) and (101) for CdS. Scanning electron micrographs showed nanorod structures for the TiO2 thin films deposited at a pH value equal 0.7. Optical results showed the CdS deposited on nanorod TiO2 exhibited increased absorption ability in the visible light, indicating an increased photocatalytic activity for TiO2/CdS core-shell nanorods in the visible light. When illuminated with a UV-Vis light source, the TiO2/CdS core-shell films displayed high responses. A composite exists between the TiO2 nanostructure and CdS NPs because the film absorbs the incident light located in both the visible and UV-Vis regions. A higher response to UV-Vis light was attained with the use of TiO2 NRAs/CdS NPs films prepared by CBD. This approach offers a technique for fabricating photoelectrodes.

The hidden economic burden of air pollution-related morbidity: evidence from the Aphekom project.

PubMed

Chanel, Olivier; Perez, Laura; Künzli, Nino; Medina, Sylvia

2016-12-01

Public decision-makers commonly use health impact assessments (HIA) to quantify the impacts of various regulation policies. However, standard HIAs do not consider that chronic diseases (CDs) can be both caused and exacerbated by a common factor, and generally focus on exacerbations. As an illustration, exposure to near road traffic-related pollution (NRTP) may affect the onset of CDs, and general ambient or urban background air pollution (BP) may exacerbate these CDs. We propose a comprehensive HIA that explicitly accounts for both the acute effects and the long-term effects, making it possible to compute the overall burden of disease attributable to air pollution. A case study applies the two HIA methods to two CDs-asthma in children and coronary heart disease (CHD) in adults over 65-for ten European cities, totaling 1.89 million 0-17-year-old children and 1.85 million adults aged 65 and over. We compare the current health effects with those that might, hypothetically, be obtained if exposure to NRTP was equally low for those living close to busy roads as it is for those living farther away, and if annual mean concentrations of both PM 10 and NO 2 -taken as markers of general urban air pollution-were no higher than 20 μg/m 3 . Returning an assessment of € 0.55 million (95 % CI 0-0.95), the HIA based on acute effects alone accounts for only about 6.2 % of the annual hospitalization burden computed with the comprehensive method [€ 8.81 million (95 % CI 3-14.4)], and for about 0.15 % of the overall economic burden of air pollution-related CDs [€ 370 million (95 % CI 106-592)]. Morbidity effects thus impact the health system more directly and strongly than previously believed. These findings may clarify the full extent of benefits from any public health or environmental policy involving CDs due to and exacerbated by a common factor.

Evaluation of a clinical dehydration scale in children requiring intravenous rehydration.

PubMed

Kinlin, Laura M; Freedman, Stephen B

2012-05-01

To evaluate the reliability and validity of a previously derived clinical dehydration scale (CDS) in a cohort of children with gastroenteritis and evidence of dehydration. Participants were 226 children older than 3 months who presented to a tertiary care emergency department and required intravenous rehydration. Reliability was assessed at treatment initiation, by comparing the scores assigned independently by a trained research nurse and a physician. Validity was assessed by using parameters reflective of disease severity: weight gain, baseline laboratory results, willingness of the physician to discharge the patient, hospitalization, and length of stay. Interobserver reliability was moderate, with a weighted κ of 0.52 (95% confidence interval [CI] 0.41, 0.63). There was no correlation between CDS score and percent weight gain, a proxy measure of fluid deficit (Spearman correlation coefficient = -0.03; 95% CI -0.18, 0.12). There were, however, modest and statistically significant correlations between CDS score and several other parameters, including serum bicarbonate (Pearson correlation coefficient = -0.35; 95% CI -0.46, -0.22) and length of stay (Pearson correlation coefficient = 0.24; 95% CI 0.11, 0.36). The scale's discriminative ability was assessed for the outcome of hospitalization, yielding an area under the receiver operating characteristic curve of 0.65 (95% CI 0.57, 0.73). In children administered intravenous rehydration, the CDS was characterized by moderate interobserver reliability and weak associations with objective measures of disease severity. These data do not support its use as a tool to dictate the need for intravenous rehydration or to predict clinical course.

Antimicrobial activity, cytotoxicity and DNA binding studies of carbon dots

NASA Astrophysics Data System (ADS)

Jhonsi, Mariadoss Asha; Ananth, Devanesan Arul; Nambirajan, Gayathri; Sivasudha, Thilagar; Yamini, Rekha; Bera, Soumen; Kathiravan, Arunkumar

2018-05-01

In recent years, quantum dots (QDs) are one of the most promising nanomaterials in life sciences community due to their unexploited potential in biomedical applications; particularly in bio-labeling and sensing. In the advanced nanomaterials, carbon dots (CDs) have shown promise in next generation bioimaging and drug delivery studies. Therefore the knowledge of the exact nature of interaction with biomolecules is of great interest to designing better biosensors. In this study, the interaction between CDs derived from tamarind and calf thymus DNA (ct-DNA) has been studied by vital spectroscopic techniques, which revealed that the CDs could interact with DNA via intercalation. The apparent association constant has been deduced from the absorption spectral changes of ct-DNA-CDs using the Benesi-Hildebrand equation. From the DNA induced emission quenching experiments the apparent DNA binding constant of the CDs (Kapp) have also been evaluated. Furthermore, we have analyzed the antibacterial and antifungal activity of CDs using disc diffusion assay method which exhibited excellent activity against E. coli and C. albicans with inhibition zone in the range of 7-12 mm. The biocompatible nature of CDs was confirmed by an in vitro cytotoxicity test on L6 normal rat myoblast cells by using MTT assay. The cell viability is not affected till the high dosage of CDs (200 μg/mL) for >48 h. As a consequence of the work, future development of CDs for microbial control and DNA sensing among the various biomolecules is possible in view of emerging biofields.

Effect of silver doping on the elastic properties of CdS nanoparticles

NASA Astrophysics Data System (ADS)

Dey, P. C.; Das, R.

2018-05-01

CdS and Ag doped CdS (CdS/Ag) nanoparticles have been prepared via chemical method from a Cadmium acetate precursor and Thiourea. The synthesized CdS and CdS/Ag nanoparticles have been characterized by the X-ray Diffraction and High Resolution Transmission Electron Microscope. Here, these nanoparticles have been synthesized at room temperature and all the characterization have also been done at room temperature only. The XRD results reveal that the products are crystalline with cubic zinc blende structure. HRTEM images show that the prepared nanoparticles are nearly spherical in shape. Williamson-Hall method and Size-Strain Plot (SSP) have been used to study the individual contribution of crystalline sizes and lattice strain on the peak broadening of the CdS and CdS/Ag nanoparticles. The different modified model of Williamson-Hall method such as, uniform deformation model, uniform stress deformation model and uniform energy density deformation model and SSP method have been used to calculate the different physical parameter such as lattice strain, stress and energy density for all diffraction peaks of the XRD, corresponding to the CdS and silver doped CdS (CdS/Ag). The obtained results reveal that the average particle size of the prepared CdS and CdS/Ag nanoparticles estimated from the HRTEM images, Williamson-Hall analysis and SSP method are highly correlated with each other. Further, all these result confirms that doping of Ag significantly affects the elastic properties of CdS.

Turn-off fluorescence sensor for the detection of ferric ion in water using green synthesized N-doped carbon dots and its bio-imaging.

PubMed

Edison, Thomas Nesakumar Jebakumar Immanuel; Atchudan, Raji; Shim, Jae-Jin; Kalimuthu, Senthilkumar; Ahn, Byeong-Cheol; Lee, Yong Rok

2016-05-01

This paper reports turn-off fluorescence sensor for Fe(3+) ion in water using fluorescent N-doped carbon dots as a probe. A simple and efficient hydrothermal carbonization of Prunus avium fruit extract for the synthesis of fluorescent nitrogen-doped carbon dots (N-CDs) is described. This green approach proceeds quickly and provides good quality N-CDs. The mean size of synthesized N-CDs was approximately 7nm calculated from the high-resolution transmission electron microscopic images. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy revealed the presence of -OH, -NH2, -COOH, and -CO functional groups over the surface of CDs. The N-CDs showed excellent fluorescent properties, and emitted blue fluorescence at 411nm upon excitation at 310nm. The calculated quantum yield of the synthesized N-CDs is 13% against quinine sulfate as a reference fluorophore. The synthesized N-CDs were used as a fluorescent probe towards the selective and sensitive detection of biologically important Fe(3+) ions in water by fluorescence spectroscopy and for bio-imaging of MDA-MB-231 cells. The limit of detection (LOD) and the Stern-Volmer quenching constant for the synthesized N-CDs were 0.96μM and 2.0958×10(3)M of Fe(3+) ions. The green synthesized N-CDs are efficiently used as a promising candidate for the detection of Fe(3+) ions and bio-imaging. Copyright © 2016 Elsevier B.V. All rights reserved.

The importance of batteries in unmanned missions

NASA Technical Reports Server (NTRS)

Klein, John W.

1989-01-01

The planetary program has historically used batteries to supply peak power needs for mission specific applications. Any time that additional power has been required in order to meet peak power demands or those applications where only limited amounts of power were required, batteries have always been used. Up until the mid to late 70's they have performed their task admirably. Recently, however, we have all become aware of the growing problem of developing reliable NiCd batteries for long mission and high cycle life applications. Here, the role rechargeable batteries will play for future planetary and earth observing spacecraft is discussed. In conclusion, NiCds have been and will continue to be the mainstay of the power system engineers tools for peak power production. Recent experience has tarnished its once sterling reputation. However, the industry has stood up to this challenge and implemented wide ranging plans to rectify the situation. These efforts should be applauded and supported as new designs and materials become available. In addition, project managers must become aware of their responsibility to test their batteries and insure quality and mission operating characteristics. Without this teamwork, the role of NiCds in the future will diminish, and other batteries, not as optimum for high performance applications (low mass and volume) will take their place.

Mechanochemical approach for the capping of mixed core CdS/ZnS nanocrystals: Elimination of cadmium toxicity.

PubMed

Bujňáková, Zdenka; Baláž, Matej; Dutková, Erika; Baláž, Peter; Kello, Martin; Mojžišová, Gabriela; Mojžiš, Ján; Vilková, Mária; Imrich, Ján; Psotka, Miroslav

2017-01-15

The wet mechanochemical procedure for the capping of the CdS and CdS/ZnS quantum dot nanocrystals is reported. l-cysteine and polyvinylpyrrolidone (PVP) were used as capping agents. When using l-cysteine, the dissolution of cadmium(II) was almost none for CdS/ZnS nanocrystals. Moreover, prepared CdS- and CdS/ZnS-cysteine nanosuspensions exhibited unimodal particle size distributions with very good stability, which was further supported by the zeta potential measurements. The Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy showed the successful embedment of cysteine into the structure of the nanocrystals. Additionally, the optical properties were examined, and the results showed that the cysteine nanosuspension has promising fluorescence properties. On the other hand, PVP was not determined to be a very suitable capping agent for the present system. In this case, the release of cadmium(II) was higher in comparison to the l-cysteine capped samples. The nanosuspensions were successfully used for in vitro studies on selected cancer cell lines. Using fluorescence microscopy, it was evidenced that the nanocrystals enter the cell and that they can serve as imaging agents in biomedical applications. Copyright © 2016. Published by Elsevier Inc.

Reduced graphene oxide-mediated Z-scheme BiVO4/CdS nanocomposites for boosted photocatalytic decomposition of harmful organic pollutants.

PubMed

Clament Sagaya Selvam, N; Kim, Yeong Gyeong; Kim, Dong Jin; Hong, Won-Hwa; Kim, Woong; Park, Sung Hyuk; Jo, Wan-Kuen

2018-09-01

The efficient photocatalytic degradation of harmful organic pollutants (isoniazid (ISN) and 1,4-dioxane (DX)) via the Z-scheme electron transfer mechanism was accomplished using a photostable composite photocatalyst consisting of BiVO 4 , CdS, and reduced graphene oxide (RGO). Compared to their pristine counterparts, the RGO-mediated Z-scheme CdS/BiVO 4 (CdS/RGO-BiVO 4 ) nanocomposites exhibited superior degradation activities, mainly attributed to the prolonged charge separation. RGO was found to be involved in visible-light harvesting and acted as a solid-state electron mediator at the CdS/BiVO 4 interface to realize an effective Z-scheme electron transfer pathway, avoid photocatalyst self-oxidation, and lengthen the life span of charge carriers. The results of reactive species scavenging experiments, photoluminescence measurements, and transient photocurrent measurements, as well as the calculated band potentials of the synthesized photocatalysts, supported the Z-scheme electron/hole pair separation mechanism. Additionally, the intermediates formed during the degradation of ISN and DX were identified, and a possible fragmentation pattern was proposed. This systematic work aims to develop photostable Z-scheme composites as unique photocatalytic systems for the efficient removal of harmful organic pollutants. Copyright © 2018 Elsevier B.V. All rights reserved.

Beyond the EPR: Complementary roles of the hospital-wide electronic health record and clinical departmental systems

PubMed Central

2009-01-01

Background Many hospital departments have implemented small clinical departmental systems (CDSs) to collect and use patient data for documentation as well as for other department-specific purposes. As hospitals are implementing institution-wide electronic patient records (EPRs), the EPR is thought to be integrated with, and gradually substitute the smaller systems. Many EPR systems however fail to support important clinical workflows. Also, successful integration of systems has proven hard to achieve. As a result, CDSs are still in widespread use. This study was conducted to see which tasks are supported by CDSs and to compare this to the support offered by the EPR. Methods Semi-structured interviews with users of 16 clinicians using 15 different clinical departmental systems (CDS) at a Medium-sized University hospital in Norway. Inductive analysis of transcriptions from the audio taped interviews. Results The roles of CDSs were complementary to those of the hospital-wide EPR system. The use of structured patient data was a characteristic feature. This facilitated quality development and supervision, tasks that were poorly supported by the EPR system. The structuring of the data also improved filtering of information to better support clinical decision-making. Because of the high value of the structured patient data, the users put much effort in maintaining their integrity and representativeness. Employees from the departments were also engaged in the funding, development, implementation and maintenance of the systems. Conclusion Clinical departmental systems are vital to the activities of a clinical hospital department. The development, implementation and clinical use of such systems can be seen as bottom-up, user-driven innovations. PMID:19523198

Clinical Decision Support to Efficiently Identify Patients Eligible for Advanced Heart Failure Therapies.

PubMed

Evans, R Scott; Kfoury, Abdallah G; Horne, Benjamin D; Lloyd, James F; Benuzillo, Jose; Rasmusson, Kismet D; Roberts, Colleen; Lappé, Donald L

2017-10-01

Patients who need and receive timely advanced heart failure (HF) therapies have better long-term survival. However, many of these patients are not identified and referred as soon as they should be. A clinical decision support (CDS) application sent secure email notifications to HF patients' providers when they transitioned to advanced disease. Patients identified with CDS in 2015 were compared with control patients from 2013 to 2014. Kaplan-Meier methods and Cox regression were used in this intention-to-treat analysis to compare differences between visits to specialized and survival. Intervention patients were referred to specialized heart facilities significantly more often within 30 days (57% vs 34%; P < .001), 60 days (69% vs 44%; P < .0001), 90 days (73% vs 49%; P < .0001), and 180 days (79% vs 58%; P < .0001). Age and sex did not predict heart facility visits, but renal disease did and patients of nonwhite race were less likely to visit specialized heart facilities. Significantly more intervention patients were found to be alive at 30 (95% vs 92%; P = .036), 60 (95% vs 90%; P = .0013), 90 (94% vs 87%; P = .0002), and 180 days (92% vs 84%; P = .0001). Age, sex, and some comorbid diseases were also predictors of mortality, but race was not. We found that CDS can facilitate the early identification of patients needing advanced HF therapy and that its use was associated with significantly more patients visiting specialized heart facilities and longer survival. Copyright © 2017 Elsevier Inc. All rights reserved.

Rapid Synthesis of Carbon Dots by Hydrothermal Treatment of Lignin

PubMed Central

Chen, Wenxin; Hu, Chaofan; Yang, Yunhua; Cui, Jianghu; Liu, Yingliang

2016-01-01

A rapid approach has been developed for the fluorescent carbon dots (CDs) by the hydrothermal treatment of lignin in the presence of H2O2. The as-synthesized CDs were found to emit blue photoluminescence with excellent photostability. Moreover, the CDs displayed biocompatibility, low cytotoxicity, and high water solubility properties. Finally, the as-resulted CDs were demonstrated to be excellent probes for bioimaging and biosensing applications. PMID:28773309

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Bo; Zhang, Xiaosong, E-mail: zhangxiaosong@tjut.edu.cn; Li, Lan

Trap-rich CdS nanocrystals were synthesized by employing CdSt{sub 2} and sulfur as precursors via thermal decomposition. Furthermore, X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), absorption and photoluminescence (PL) spectra were used to characterize structure, morphology and luminescence properties of CdS nanocrystals (NCs). CdS NCs have a broad emission across 500–700 nm under the excitation of blue light with 460 nm, consequently, white light can be produced by mixing broad emission from CdS NCs excited by blue light, with the remaining blue light. In addition, the broad emission generation is closely and inseparably related to surface defects. Moreover, LaMer modelmore » was used to explain the phenomenon that the intensity of the trap emission gradually decreases as the reaction time increases in contrast with that of the band-edge emission. - Graphical abstract: Trap-rich CdS nanocrystals were synthesized. Furthermore, white light is produced by mixing broad emission across 500–700 nm from CdS NCs excited by blue light, in combination with the remaining blue light. - Highlights: • Trap-rich CdS nanocrystals were synthesized. • CdS NCs have a broad emission across 500–700 nm under the excitation of blue light. • White light can be produced by mixing broad emission with the remaining blue light.« less

Ultrasensitive detection of amifostine and alkaline phosphatase based on the growth of CdS quantum dots.

PubMed

Na, Weidan; Liu, Siyu; Liu, Xiaotong; Su, Xingguang

2015-11-01

In this study, we reported a simple and sensitive fluorescence nanosensor for rapid detection of amifostine and alkaline phosphatase (ALP). The novel nanosensor was based on the fluorescence "turn on-off" of CdS quantum dots (QDs). Firstly, Cd(2+) cation could react with S(2-) anion to generate fluorescent CdS QDs in the presence of amifostine. The fluorescence (FL) intensity of amifostine-capped CdS QDs (Amifostine-CdS QDs) was increased with the increasing amounts of amifostine, and could be used for amifostine detection. However, amifostine could be converted to 2-(3-aminopropylamino) ethanethiol (WR1065) in the presence of ALP based on the dephosphorylation of ALP. Under the optimum conditions, the affinity of WR1065 to CdS QDs was weaker than that of amifostine. Therefore the new generation of WR1065-CdS QDs would reduce the FL intensity with the increase of ALP concentration, and the fluorescence of CdS QDs was turn off. The metabolic process of amifostine in the presence of alkaline phosphatase could be also studied via the change of FL intensity of CdS QDs. The present method was cost-effective, convenient, and does not require any complicated synthetic procedures. Copyright © 2015 Elsevier B.V. All rights reserved.

One-pot synthesis of CdS nanocrystals hybridized with single-layer transition-metal dichalcogenide nanosheets for efficient photocatalytic hydrogen evolution.

PubMed

Chen, Junze; Wu, Xue-Jun; Yin, Lisha; Li, Bing; Hong, Xun; Fan, Zhanxi; Chen, Bo; Xue, Can; Zhang, Hua

2015-01-19

Exploration of low-cost and earth-abundant photocatalysts for highly efficient solar photocatalytic water splitting is of great importance. Although transition-metal dichalcogenides (TMDs) showed outstanding performance as co-catalysts for the hydrogen evolution reaction (HER), designing TMD-hybridized photocatalysts with abundant active sites for the HER still remains challenge. Here, a facile one-pot wet-chemical method is developed to prepare MS2-CdS (M=W or Mo) nanohybrids. Surprisedly, in the obtained nanohybrids, single-layer MS2 nanosheets with lateral size of 4-10 nm selectively grow on the Cd-rich (0001) surface of wurtzite CdS nanocrystals. These MS2-CdS nanohybrids possess a large number of edge sites in the MS2 layers, which are active sites for the HER. The photocatalytic performances of WS2-CdS and MoS2-CdS nanohybrids towards the HER under visible light irradiation (>420 nm) are about 16 and 12 times that of pure CdS, respectively. Importantly, the MS2-CdS nanohybrids showed enhanced stability after a long-time test (16 h), and 70% of catalytic activity still remained. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

MWCNT/CdS hybrid nanocomposite for enhanced photocatalytic activity

NASA Astrophysics Data System (ADS)

Chaudhary, Deepti; Khare, Neeraj; Vankar, V. D.

2016-05-01

Multi-walled carbon nanotubes (MWCNT)/CdS hybrid nanocomposite were synthesized by one step hydrothermal method. MWCNTs were used as a substrate for the growth of CdS nanoparticles. MWCNT/CdS nanocomposite and pure CdS were characterized by XRD, TEM, UV-vis and photoluminescence spectroscopy. HRTEM study confirms the intimate contact of CdS with MWCNT. The photocatalytic activity of nanocomposite was studied for the degradation of methylene blue dye under UV irradiation. The enhanced photocatalytic activity of MWCNT/CdS nanocomposite as compared to pure CdS has been attributed to reduced recombination of photogenerated charge carriers due to interfacial electron transfer from CdS to MWCNT.

Creatine deficiency syndromes.

PubMed

Schulze, Andreas

2013-01-01

The lack of creatine in the central nervous system causes a severe but treatable neurological disease. Three inherited defects, AGAT, GAMT, and CrT deficiency, compromising synthesis and transport of creatine have been discovered recently. Together these so-called creatine deficiency syndromes (CDS) might represent the most frequent metabolic disorders with a primarily neurological phenotype. Patients with CDS present with global developmental delays, mental retardation, speech impairment especially affecting active language, seizures, extrapyramidal movement disorder, and autism spectrum disorder. The two defects in the creatine synthesis, AGAT and GAMT, are autosomal recessive disorders. They can be diagnosed by analysis of the creatine, guanidinoacetate, and creatinine in body fluids. Treatment is available and, especially when introduced in infancy, has a good outcome. The defect of creatine transport, CrT, is an X-linked condition and perhaps the most frequent reasons for X-linked mental retardation. Diagnosis is made by an increased ratio of creatine to creatinine in urine, but successful treatment still needs to be explored. CDS are under-diagnosed because easy to miss in standard diagnostic workup. Because CDS represent a frequent cause of cognitive and neurological impairment that is treatable they warrant consideration in the workup for genetic mental retardation syndromes, for intractable seizure disorders, and for neurological diseases with a predominant lack of active speech. Copyright © 2013 Elsevier B.V. All rights reserved.

Role of Surface-Capping Ligands in Photoexcited Electron Transfer between CdS Nanorods and [FeFe] Hydrogenase and the Subsequent H 2 Generation

DOE PAGES

Wilker, Molly B.; Utterback, James K.; Greene, Sophie; ...

2017-12-08

Complexes of CdS nanorods and [FeFe] hydrogenase from Clostridium acetobutylicum have been shown to photochemically produce H 2. This study examines the role of the ligands that passivate the nanocrystal surfaces in the electron transfer from photoexcited CdS to hydrogenase and the H 2 generation that follows. We functionalized CdS nanorods with a series of mercaptocarboxylate surface-capping ligands of varying lengths and measured their photoexcited electron relaxation by transient absorption (TA) spectroscopy before and after hydrogenase adsorption. Rate constants for electron transfer from the nanocrystals to the enzyme, extracted by modeling of TA kinetics, decrease exponentially with ligand length, suggestingmore » that the ligand layer acts as a barrier to charge transfer and controls the degree of electronic coupling. Relative light-driven H 2 production efficiencies follow the relative quantum efficiencies of electron transfer, revealing the critical role of surface-capping ligands in determining the photochemical activity of these nanocrystal-enzyme complexes. Our results suggest that the H 2 production in this system could be maximized with a choice of a surface-capping ligand that decreases the distance between the nanocrystal surface and the electron injection site of the enzyme.« less

Role of Surface-Capping Ligands in Photoexcited Electron Transfer between CdS Nanorods and [FeFe] Hydrogenase and the Subsequent H 2 Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilker, Molly B.; Utterback, James K.; Greene, Sophie

Complexes of CdS nanorods and [FeFe] hydrogenase from Clostridium acetobutylicum have been shown to photochemically produce H 2. This study examines the role of the ligands that passivate the nanocrystal surfaces in the electron transfer from photoexcited CdS to hydrogenase and the H 2 generation that follows. We functionalized CdS nanorods with a series of mercaptocarboxylate surface-capping ligands of varying lengths and measured their photoexcited electron relaxation by transient absorption (TA) spectroscopy before and after hydrogenase adsorption. Rate constants for electron transfer from the nanocrystals to the enzyme, extracted by modeling of TA kinetics, decrease exponentially with ligand length, suggestingmore » that the ligand layer acts as a barrier to charge transfer and controls the degree of electronic coupling. Relative light-driven H 2 production efficiencies follow the relative quantum efficiencies of electron transfer, revealing the critical role of surface-capping ligands in determining the photochemical activity of these nanocrystal-enzyme complexes. Our results suggest that the H 2 production in this system could be maximized with a choice of a surface-capping ligand that decreases the distance between the nanocrystal surface and the electron injection site of the enzyme.« less

CdS nanoparticles immobilized on porous carbon polyhedrons derived from a metal-organic framework with enhanced visible light photocatalytic activity for antibiotic degradation

NASA Astrophysics Data System (ADS)

Yang, Cao; Cheng, Jianhua; Chen, Yuancai; Hu, Yongyou

2017-10-01

The CdS/MOF-derived porous carbon (MPC) composite as an efficient visible-light-driven photocatalyst was prepared through the pyrolysis of ZIF-8 and subsequent growth of CdS. The porous and functionalized MPC enables intimate and discrete growth of CdS nanoparticles. This unique structure not only reduces the bulk recombination owing to nano-size effect of CdS, but also suppresses the surface recombination due to the discrete growth of CdS nanoparticles on MPC polyhedrons, which facilitates electron transfer and charge separation. Moreover, such a composite material possessed good adsorption ability toward the antibiotic pollutants because of the amino-functionalized surface. As a result, the as-prepared CdS/MPC composites showed excellent photocatalytic performance for the antibiotic degradation, significantly improving the photoactivity of CdS. Importantly, the CdS/MPC composite with the CdS loading of 20 wt% exhibited the highest photocatalytic efficiency of approximately 91% and apparent rate constant of 0.024 min-1.

Synthesis of pore-variable mesoporous CdS and evaluation of its photocatalytic activity in degrading methylene blue

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Wei-Min, E-mail: chm_zhangwm@ujn.edu.cn; Jiang, Yao-Quan; Cao, Xiao-Yan

2013-10-15

Graphical abstract: - Highlights: • Self-templated synthesis of tubular CdS. • Cadmium complexes of aliphatic acids sustain the network of mesoporous structures. • Aliphatic acids affect the phase composition and particle size. • Pore size and volume vary with aliphatic acids having different hydrocarbonyl. - Abstract: In this study, mesoporous CdS polycrystallites have been synthesized using aliphatic acids of hexanoic acid, octanoic acid, and oleic acid as coordinating and capping agents, respectively. The fibrous Cd–fatty acid salts act as a template to form the tubular CdS. The organic species are found to be necessary for maintaining the network of mesoporousmore » CdS. The characterization results indicate that the shorter carbon chain length in aliphatic acids favors the wurtzite phase and particle size growth the specific surface area, pore diameter and pore volume show a monotonic raise with increasing carbon chain. The photocatalytic activities of mesoporous CdS tubes exhibit much higher efficiency than those of nanosized CdS powders in decolorizing methylene blue under simulated visible light.« less

Structural and Spectroscopic Studies of Sm3+/CdS Nanocrystallites in Sol-Gel TiO2-ZrO2 Matrix

NASA Astrophysics Data System (ADS)

Karthika, S.; Prathibha, Vasudevan; Ann, Mary K. A.; Viji, Vidyadharan; Biju, P. R.; Unnikrishnan, N. V.

2014-02-01

A sol-gel method was used to prepare titania-zirconia matrices doped with Sm3+/CdS nanocrystallites. The structural properties of the matrices were characterized using transmission electron microscopy (TEM), thermogravimetric analysis (TGA), differential thermal analysis (DTA), and Fourier-transform infrared spectroscopy studies. The thermal stability of the material was determined by TGA/DTA analysis. The absorption spectrum shows the characteristic peaks of the Sm3+ ions and the absorption peak corresponding to the CdS nanocrystallites. The optical bandgap and size of the CdS nanoparticles were calculated from the absorption spectrum. From TEM, the interplanar distance ( d) was estimated to be 3.533 Å, which matches with the (1 0 0) plane of bulk CdS. The measurements yield a nanocrystallite size of around 7.8 nm. The optical absorption and emission spectra confirmed the formation of CdS nanoparticles along with samarium ions in the titania-zirconia matrices. The fluorescence intensity of the samarium ions was found to be greatly enhanced by codoping with CdS nanocrystallites.

Additive interaction of carbon dots extracted from soluble coffee and biogenic silver nanoparticles against bacteria

NASA Astrophysics Data System (ADS)

Andrade, Patricia F.; Nakazato, Gerson; Durán, Nelson

2017-06-01

It is known the presence of carbon dots (CDs) in carbohydrate based foods. CDs extracted from coffee grounds and instant coffee was also published. CDs from soluble coffee revealed an average size of 4.4 nm. CDs were well-dispersed in water, fluorescent and we have characterized by XPS, XRD analysis, fluorescence and by FTIR spectra. The MIC value by serial micro-dilution assays for CDs on S. aureus ATCC 25923 was 250 μg/mL and E. coli ATCC 25922 >1000 ug/mL. For silver nanoparticles biogenically synthesized was 6.7 μg/mL. Following the checkerboard assay with combining ½ MIC values of the MICs of 125 μg/mL of carbon dots and 3.4 μg/mL of silver nanoparticles, following the fractionated inhibitory concentration (FIC) index methodology, on S. aureus gave a fractionated inhibitory concentration (FIC) value of 1.0, meaning additive interaction. In general, the unfunctionalized CDs showed to be inefficient as antibacterial compounds, however the CDs extracted from Coffee powder and together silver nanoparticles appeared interesting as antibacterial association.

Damage tolerance protein Mus81 associates with the FHA1 domain of checkpoint kinase Cds1.

PubMed

Boddy, M N; Lopez-Girona, A; Shanahan, P; Interthal, H; Heyer, W D; Russell, P

2000-12-01

Cds1, a serine/threonine kinase, enforces the S-M checkpoint in the fission yeast Schizosaccharomyces pombe. Cds1 is required for survival of replicational stress caused by agents that stall replication forks, but how Cds1 performs these functions is largely unknown. Here we report that the forkhead-associated-1 (FHA1) protein-docking domain of Cds1 interacts with Mus81, an evolutionarily conserved damage tolerance protein. Mus81 has an endonuclease homology domain found in the XPF nucleotide excision repair protein. Inactivation of mus81 reveals a unique spectrum of phenotypes. Mus81 enables survival of deoxynucleotide triphosphate starvation, UV radiation, and DNA polymerase impairment. Mus81 is essential in the absence of Bloom's syndrome Rqh1 helicase and is required for productive meiosis. Genetic epistasis studies suggest that Mus81 works with recombination enzymes to properly replicate damaged DNA. Inactivation of Mus81 triggers a checkpoint-dependent delay of mitosis. We propose that Mus81 is involved in the recruitment of Cds1 to aberrant DNA structures where Cds1 modulates the activity of damage tolerance enzymes.

Double heterojunction nanowire photocatalysts for hydrogen generation

NASA Astrophysics Data System (ADS)

Tongying, P.; Vietmeyer, F.; Aleksiuk, D.; Ferraudi, G. J.; Krylova, G.; Kuno, M.

2014-03-01

Charge separation and charge transfer across interfaces are key aspects in the design of efficient photocatalysts for solar energy conversion. In this study, we investigate the hydrogen generating capabilities and underlying photophysics of nanostructured photocatalysts based on CdSe nanowires (NWs). Systems studied include CdSe, CdSe/CdS core/shell nanowires and their Pt nanoparticle-decorated counterparts. Femtosecond transient differential absorption measurements reveal how semiconductor/semiconductor and metal/semiconductor heterojunctions affect the charge separation and hydrogen generation efficiencies of these hybrid photocatalysts. In turn, we unravel the role of surface passivation, charge separation at semiconductor interfaces and charge transfer to metal co-catalysts in determining photocatalytic H2 generation efficiencies. This allows us to rationalize why Pt nanoparticle decorated CdSe/CdS NWs, a double heterojunction system, performs best with H2 generation rates of ~434.29 +/- 27.40 μmol h-1 g-1 under UV/Visible irradiation. In particular, we conclude that the CdS shell of this double heterojunction system serves two purposes. The first is to passivate CdSe NW surface defects, leading to long-lived charges at the CdSe/CdS interface capable of carrying out reduction chemistries. Upon photoexcitation, we also find that CdS selectively injects charges into Pt NPs, enabling simultaneous reduction chemistries at the Pt NP/solvent interface. Pt nanoparticle decorated CdSe/CdS NWs thus enable reduction chemistries at not one, but rather two interfaces, taking advantage of each junction's optimal catalytic activities.Charge separation and charge transfer across interfaces are key aspects in the design of efficient photocatalysts for solar energy conversion. In this study, we investigate the hydrogen generating capabilities and underlying photophysics of nanostructured photocatalysts based on CdSe nanowires (NWs). Systems studied include CdSe, CdSe/CdS core/shell nanowires and their Pt nanoparticle-decorated counterparts. Femtosecond transient differential absorption measurements reveal how semiconductor/semiconductor and metal/semiconductor heterojunctions affect the charge separation and hydrogen generation efficiencies of these hybrid photocatalysts. In turn, we unravel the role of surface passivation, charge separation at semiconductor interfaces and charge transfer to metal co-catalysts in determining photocatalytic H2 generation efficiencies. This allows us to rationalize why Pt nanoparticle decorated CdSe/CdS NWs, a double heterojunction system, performs best with H2 generation rates of ~434.29 +/- 27.40 μmol h-1 g-1 under UV/Visible irradiation. In particular, we conclude that the CdS shell of this double heterojunction system serves two purposes. The first is to passivate CdSe NW surface defects, leading to long-lived charges at the CdSe/CdS interface capable of carrying out reduction chemistries. Upon photoexcitation, we also find that CdS selectively injects charges into Pt NPs, enabling simultaneous reduction chemistries at the Pt NP/solvent interface. Pt nanoparticle decorated CdSe/CdS NWs thus enable reduction chemistries at not one, but rather two interfaces, taking advantage of each junction's optimal catalytic activities. Electronic supplementary information (ESI) available: Details of NW syntheses, processing and characterization. Additional TEM images of CdS, CdSe and CdSe/CdS core/shell NWs. NW concentration and cross section estimates. Details of the Pt NP decoration. Additional TEM images of Pt NP decorated CdS, CdSe and CdSe/CdS core/shell NWs. Size distribution of Pt NPs for CdSe/Pt NP and CdSe/CdS/Pt NP NWs. Xe arc lamp spectrum. Details of H2 generation experiments. Estimated photon absorption rate. Details of TDA measurements. TDA spectra and kinetics of CdS and CdS/Pt NP NWs. Plot illustrating CdSe NW band edge bleach kinetics. Comparison of CdSe band edge bleach kinetics in CdSe/CdS core/shell NWs when excited at λexc = 387 nm and λexc = 560 nm. Comparison of CdSe band edge bleach kinetics in CdSe/Pt NP NWs when excited at λexc = 387 nm and λexc = 560 nm. Bar graph showing H2 generation efficiencies of CdS and CdS/Pt NP NWs. Bleach kinetics of CdSe/CdS/Pt NP NWs at λexc = 387 nm and λexc = 560 nm. Comparison of CdS band edge bleach kinetics in CdS/Pt NP, and CdSe/CdS core/shell NWs when excited at λexc = 387 nm. See DOI: 10.1039/c4nr00298a

Kelvin probe imaging of photo-injected electrons in metal oxide nanosheets from metal sulfide quantum dots under remote photochromic coloration

NASA Astrophysics Data System (ADS)

Kondo, A.; Yin, G.; Srinivasan, N.; Atarashi, D.; Sakai, E.; Miyauchi, M.

2015-07-01

Metal oxide and quantum dot (QD) heterostructures have attracted considerable recent attention as materials for developing efficient solar cells, photocatalysts, and display devices, thus nanoscale imaging of trapped electrons in these heterostructures provides important insight for developing efficient devices. In the present study, Kelvin probe force microscopy (KPFM) of CdS quantum dot (QD)-grafted Cs4W11O362- nanosheets was performed before and after visible-light irradiation. After visible-light excitation of the CdS QDs, the Cs4W11O362- nanosheet surface exhibited a decreased work function in the vicinity of the junction with CdS QDs, even though the Cs4W11O362- nanosheet did not absorb visible light. X-ray photoelectron spectroscopy revealed that W5+ species were formed in the nanosheet after visible-light irradiation. These results demonstrated that excited electrons in the CdS QDs were injected and trapped in the Cs4W11O362- nanosheet to form color centers. Further, the CdS QDs and Cs4W11O362- nanosheet composite films exhibited efficient remote photochromic coloration, which was attributed to the quantum nanostructure of the film. Notably, the responsive wavelength of the material is tunable by adjusting the size of QDs, and the decoloration rate is highly efficient, as the required length for trapped electrons to diffuse into the nanosheet surface is very short owing to its nanoscale thickness. The unique properties of this photochromic device make it suitable for display or memory applications. In addition, the methodology described in the present study for nanoscale imaging is expected to aid in the understanding of electron transport and trapping processes in metal oxide and metal chalcogenide heterostructure, which are crucial phenomena in QD-based solar cells and/or photocatalytic water-splitting systems.Metal oxide and quantum dot (QD) heterostructures have attracted considerable recent attention as materials for developing efficient solar cells, photocatalysts, and display devices, thus nanoscale imaging of trapped electrons in these heterostructures provides important insight for developing efficient devices. In the present study, Kelvin probe force microscopy (KPFM) of CdS quantum dot (QD)-grafted Cs4W11O362- nanosheets was performed before and after visible-light irradiation. After visible-light excitation of the CdS QDs, the Cs4W11O362- nanosheet surface exhibited a decreased work function in the vicinity of the junction with CdS QDs, even though the Cs4W11O362- nanosheet did not absorb visible light. X-ray photoelectron spectroscopy revealed that W5+ species were formed in the nanosheet after visible-light irradiation. These results demonstrated that excited electrons in the CdS QDs were injected and trapped in the Cs4W11O362- nanosheet to form color centers. Further, the CdS QDs and Cs4W11O362- nanosheet composite films exhibited efficient remote photochromic coloration, which was attributed to the quantum nanostructure of the film. Notably, the responsive wavelength of the material is tunable by adjusting the size of QDs, and the decoloration rate is highly efficient, as the required length for trapped electrons to diffuse into the nanosheet surface is very short owing to its nanoscale thickness. The unique properties of this photochromic device make it suitable for display or memory applications. In addition, the methodology described in the present study for nanoscale imaging is expected to aid in the understanding of electron transport and trapping processes in metal oxide and metal chalcogenide heterostructure, which are crucial phenomena in QD-based solar cells and/or photocatalytic water-splitting systems. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr02405f

Effects of experimental conditions on the morphologies, structures and growth modes of pulsed laser-deposited CdS nanoneedles

PubMed Central

2014-01-01

CdS nanoneedles with different morphologies, structures, and growth modes have been grown on Ni-coated Si(100) surface under different experimental conditions by pulsed laser deposition method. The effects of catalyst layer, substrate temperature, and laser pulse energy on the growth of the CdS nanoneedles were studied in detail. It was confirmed that the formation of the molten catalyst spheres is the key to the nucleation of the CdS nanoneedles by observing the morphologies of the Ni catalyst thin films annealed at different substrate temperatures. Both the substrate temperature and laser pulse energy strongly affected the growth modes of the CdS nanoneedles. The secondary growth of the smaller nanoneedles on the top of the main nanoneedles was found at appropriate conditions. A group of more completed pictures of the growth modes of the CdS nanoneedles were presented. PMID:24559455

Hydrothermal synthesis of nitrogen-doped carbon dots with real-time live-cell imaging and blood-brain barrier penetration capabilities.

PubMed

Lu, Shousi; Guo, Shanshan; Xu, Pingxiang; Li, Xiaorong; Zhao, Yuming; Gu, Wei; Xue, Ming

Nitrogen-doped carbon dots (N-CDs) were synthesized using a one-pot hydrothermal treatment with citric acid in the presence of polyethylenimine. Transmission electron microscopy analysis revealed that the N-CDs were monodispersed and quasi-spherical with an average size of ~2.6 nm. Under ultraviolet irradiation the N-CDs emitted a strong blue luminescence with a quantum yield as high as 51%. Moreover, the N-CDs exhibited a negligible cytotoxicity and could be applied as efficient nanoprobes for real-time imaging of live cells. In addition, the ability of the N-CDs to cross the blood-brain barrier (BBB) in a concentration-dependent manner was demonstrated using an in vitro BBB model. Therefore, these PEI-passivated N-CDs with real-time live-cell imaging and BBB-penetration capabilities hold promise for traceable drug delivery to the brain.

One-pot synthesis of fluorescent nitrogen-doped carbon dots with good biocompatibility for cell labeling.

PubMed

Zhang, Zhengwei; Yan, Kun; Yang, Qiulian; Liu, Yanhua; Yan, Zhengyu; Chen, Jianqiu

2017-12-01

Here we report an easy and economical hydrothermal carbonization approach to synthesize the fluorescent nitrogen-doped carbon dots (N-CDs) that was developed using citric acid and triethanolamine as the precursors. The synthesis conditions were optimized to obtain the N-CDs with superior fluorescence performances. The as-prepared N-CDs are monodispersed sphere nanoparticles with good water solubility, and exhibited strong fluorescence, favourable photostability and excitation wavelength-dependent behavior. Furthermore, the in vitro cytotoxicity and cellular labeling of N-CDs were investigated using the rat glomerular mesangial cells. The results showed the N-CDs have more inconspicuous cytotoxicity and better biosafety in comparison with ZnSe quantum dots, although both targeted the cells successfully. Considering their admirable photostability, low toxicity and good compatibility, the as-obtained N-CDs could have potential applications in biosensors, cellular imaging, and other fields. Copyright © 2017 John Wiley & Sons, Ltd.

Hydrothermal synthesis of nitrogen-doped carbon dots with real-time live-cell imaging and blood–brain barrier penetration capabilities

PubMed Central

Lu, Shousi; Guo, Shanshan; Xu, Pingxiang; Li, Xiaorong; Zhao, Yuming; Gu, Wei; Xue, Ming

2016-01-01

Nitrogen-doped carbon dots (N-CDs) were synthesized using a one-pot hydrothermal treatment with citric acid in the presence of polyethylenimine. Transmission electron microscopy analysis revealed that the N-CDs were monodispersed and quasi-spherical with an average size of ~2.6 nm. Under ultraviolet irradiation the N-CDs emitted a strong blue luminescence with a quantum yield as high as 51%. Moreover, the N-CDs exhibited a negligible cytotoxicity and could be applied as efficient nanoprobes for real-time imaging of live cells. In addition, the ability of the N-CDs to cross the blood–brain barrier (BBB) in a concentration-dependent manner was demonstrated using an in vitro BBB model. Therefore, these PEI-passivated N-CDs with real-time live-cell imaging and BBB-penetration capabilities hold promise for traceable drug delivery to the brain. PMID:27932880

[Screening for depersonalization-derealization with two items of the cambridge depersonalization scale].

PubMed

Michal, Matthias; Zwerenz, Rüdiger; Tschan, Regine; Edinger, Jens; Lichy, Marcel; Knebel, A; Tuin, Inka; Beutel, Manfred

2010-05-01

Depersonalization (DP) and derealization (DR) are considered to be highly underdiagnosed. Therefore the development of screening instruments is important. From the Cambridge Depersonalization Scale (CDS) two items were extracted discriminating best patients with clinical significant DP from patients without DP. These two Items were assembled to a short version of the CDS. This short version (CDS-2) was tested in a sample of 38 patients with clinical significant DP-DR and 49 patients without or only mild DP-DR. Scores were compared against clinical diagnoses based on a structured interview (gold standard). The CDS-2 was able to differentiate patients with clinical significant DP well from other groups (cut-off of CDS-2>or=3, sensitivity=78.9%, specifity=85.7%) and also showed high reliability (Cronbachs alpha=0.92). Therefore the CDS-2 can be considered as a useful tool for screening and identification of DP-DR.

Cultivating Fluorescent Flowers with Highly Luminescent Carbon Dots Fabricated by a Double Passivation Method.

PubMed

Han, Shuai; Chang, Tao; Zhao, Haiping; Du, Huanhuan; Liu, Shan; Wu, Baoshuang; Qin, Shenjun

2017-07-07

In this work, we present the fabrication of highly luminescent carbon dots (CDs) by a double passivation method with the assistance of Ca(OH)₂. In the reaction process, Ca 2+ protects the active functional groups from overconsumption during dehydration and carbonization, and the electron-withdrawing groups on the CD surface are converted to electron-donating groups by the hydroxyl ions. As a result, the fluorescence quantum yield of the CDs was found to increase with increasing Ca(OH)₂ content in the reaction process. A blue-shift optical spectrum of the CDs was also found with increasing Ca(OH)₂ content, which could be attributed to the increasing of the energy gaps for the CDs. The highly photoluminescent CDs obtained (quantum yield: 86%) were used to cultivate fluorescent carnations by a water culture method, while the results of fluorescence microscopy analysis indicated that the CDs had entered the plant tissue structure.

Determination of ethanol using permanganate-CdS quantum dot chemiluminescence system.

PubMed

Abolhasani, Jafar; Hassanzadeh, Javad

2015-08-01

A novel and highly sensitive chemiluminescence (CL) method for the determination of ethanol was developed based on the CdS quantum dots (QDs)-permanganate system. It was found that KMnO4 could directly oxidize CdS QDs in acidic media resulting in relatively high CL emission. A possible mechanism was proposed for this reaction based on UV/Vis absorption, fluorescence and the generated CL emission spectra. However, it was observed that ethanol had a remarkable inhibition effect on this system. This effect was exploited in the determination of ethanol within the concentration range 12-300 µg/L, with detection at 4.3 µg/L. In order to evaluate the capability of presented method, it was satisfactorily utilized in the determination of alcohol in real samples. Copyright © 2014 John Wiley & Sons, Ltd.

Predictive Analytics for Identification of Patients at Risk for QT Interval Prolongation - A Systematic Review.

PubMed

Tomaselli Muensterman, Elena; Tisdale, James E

2018-06-08

Prolongation of the heart rate-corrected QT (QTc) interval increases the risk for torsades de pointes (TdP), a potentially fatal arrhythmia. The likelihood of TdP is higher in patients with risk factors, which include female sex, older age, heart failure with reduced ejection fraction, hypokalemia, hypomagnesemia, concomitant administration of ≥ 2 QTc interval-prolonging medications, among others. Assessment and quantification of risk factors may facilitate prediction of patients at highest risk for developing QTc interval prolongation and TdP. Investigators have utilized the field of predictive analytics, which generates predictions using techniques including data mining, modeling, machine learning, and others, to develop methods of risk quantification and prediction of QTc interval prolongation. Predictive analytics have also been incorporated into clinical decision support (CDS) tools to alert clinicians regarding patients at increased risk of developing QTc interval prolongation. The objectives of this paper are to assess the effectiveness of predictive analytics for identification of patients at risk of drug-induced QTc interval prolongation, and to discuss the efficacy of incorporation of predictive analytics into CDS tools in clinical practice. A systematic review of English language articles (human subjects only) was performed, yielding 57 articles, with an additional 4 articles identified from other sources; a total of 10 articles were included in this review. Risk scores for QTc interval prolongation have been developed in various patient populations including those in cardiac intensive care units (ICUs) and in broader populations of hospitalized or health system patients. One group developed a risk score that includes information regarding genetic polymorphisms; this score significantly predicted TdP. Development of QTc interval prolongation risk prediction models and incorporation of these models into CDS tools reduces the risk of QTc interval prolongation in cardiac ICUs and identifies health-system patients at increased risk for mortality. The impact of these QTc interval prolongation predictive analytics on overall patient safety outcomes, such as TdP and sudden cardiac death relative to the cost of development and implementation, requires further study. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Designing Multi-Channel Web Frameworks for Cultural Tourism Applications: The MUSE Case Study.

ERIC Educational Resources Information Center

Garzotto, Franca; Salmon, Tullio; Pigozzi, Massimiliano

A framework for the design of multi-channel (MC) applications in the cultural tourism domain is presented. Several heterogeneous interface devices are supported including location-sensitive mobile units, on-site stationary devices, and personalized CDs that extend the on-site experience beyond the visit time thanks to personal memories gathered…

Reliability and validity of a Japanese version of the Cambridge depersonalization scale as a screening instrument for depersonalization disorder.

PubMed

Sugiura, Miyuki; Hirosawa, Masataka; Tanaka, Sumio; Nishi, Yasunobu; Yamada, Yasuyuki; Mizuno, Motoki

2009-06-01

The Cambridge Depersonalization Scale (CDS) is an instrument that has obtained reliability and validity in some countries for use in detecting depersonalization disorder under clinical conditions, but not yet in Japan under non-psychiatric conditions. The purposes of this study were to develop a Japanese version of the CDS (J-CDS) and to examine its reliability and validity as an instrument for screening depersonalization disorder under non-clinical conditions. The CDS was translated from English into Japanese and then back-translated into English by a native English-speaking American. After making the J-CDS, we examined its reliability and validity. Questionnaires that were composed of J-CDS, the Dissociative Experience Scale (DES), the Zung self-rating scale and the Maudsley Obsessional-Compulsive Inventory were administrated to 59 participants (12 patients with depersonalization disorder, 11 individuals who had recovered from depersonalization and 36 healthy controls). Cronbach's alpha and split-half reliability were 0.94 and 0.93, respectively. The J-CDS score in the depersonalization group was significantly higher than in the healthy control group. The J-CDS score was significantly correlated with scores of total DES, and DES-depersonalization. The best compromise between the true positive and false negative rate was at a cut-off point of 60, yielding a sensitivity of 1.00 and a specificity of 0.96. In this study, J-CDS showed good reliability and validity. The best cut-off point, when we use this for distinguishing individuals with depersonalization disorder from individuals without psychiatric disorders, is 60 points.

The Use of Clinical Decision Support in Reducing Diagnosis of and Treatment of Asymptomatic Bacteriuria.

PubMed

Keller, Sara C; Feldman, Leonard; Smith, Janessa; Pahwa, Amit; Cosgrove, Sara E; Chida, Natasha

2018-06-01

Clinical decision support (CDS) embedded within the electronic health record (EHR) is a potential antibiotic stewardship strategy for hospitalized patients. Reduction in urine testing and treating asymptomatic bacteriuria (ASB) is an important strategy to promote antibiotic stewardship. We created an intervention focused on reducing urine testing for asymptomatic patients at a large tertiary care center. The objective of this study was to design an intervention to reduce unnecessary urinalysis and urine culture (UC) orders as well as the treatment of ASB. We performed a quasiexperimental study among adult inpatients at a single academic institution. We implemented a bundled intervention, including information broadcast in newsletters, hospitalwide screensavers, and passive CDS messages in the EHR. We investigated the impact of this strategy on urinalysis, UC orders, and on the treatment of ASB by using an interrupted time series analysis. Our intervention led to reduced UC order as well as reduced antibiotic orders in response to urinalysis orders and UC results. This easily implementable bundle may play an important role as an antibiotic stewardship strategy. © 2018 Society of Hospital Medicine.

Single-Source Molecular Precursor for Synthesis of CdS Nanoparticles and Nanoflowers

NASA Astrophysics Data System (ADS)

Salavati-Niasari, Masoud; Sobhani, Azam

2012-04-01

CdS Semiconductor nanostructures were synthesized by using two different methods. Using triphenylphosphine (C18H15P) and oleylamine (C18H37N) as surfactant, CdS semiconductor nanocrystals with a size ranging from 30 to 90 nm can be synthesized by thermal decomposition of precursor [bis(thiosemicarbazide)cadmium(II)]. CdS nanoflowers were synthesized via hydrothermal decomposition of [bis(thiosemicarbazide) cadmium(II)] without any surfactant. X-ray diffraction (XRD) patterns confirm that the resulting samples were a pure hexagonal phase of CdS. The optical property test indicates that the absorption peak of the samples shifts towards short wavelength, and the blue shift phenomenon might be ascribed to the quantum effect.

Growth and characterization of EDTA assisted CBD-CdS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumarage, W. G. C.; Wijesundera, R. P.; Seneviratne, V. A.

2017-10-01

Chemical bath deposition of CdS (CBD-CdS) thin films with the assistance of a cationic surfactant, ethylenediamine tetraacetic acid (EDTA), is reported in this work. Also the EDTA treated CdS thin films are compared with that of conventional CBD-CdS. Fabricated thin, compact, uniform and adherent EDTA treated CdS films show enhanced effective surface area and roughness compared to conventional CBD-CdS. The grazing incidence x-ray diffraction analysis shows all the fabricated CdS films are hexagonally crystallized. EDTA-treated CdS films show excellent photo activity compared to conventional CBDCdS. The flat band potential (Vfb) value was found to be tunable with EDTA concentration.

Facile synthesis of carbon dots with superior sensing ability

NASA Astrophysics Data System (ADS)

Jin, Lin; Li, Jingguo; Liu, Liyun; Wang, Zhenling; Zhang, Xingcai

2018-04-01

Carbon dots (CDs) have various applications in biomedical and environmental field, such as bio-imaging, bio-sensing and heavy metal detection. In this study, a novel class of CDs were synthesized using a one-step hydrothermal method. The fabricated CDs displayed stable photoluminescence, good water solubility, and photo stability. Moreover, the functional groups (carboxylic acid moieties and hydroxyls) on the surface of the obtained CDs enable it with superior sensing ability (e.g., very low detectable concentration for Pb2+: 5 nmol/L). With superior detection sensitivity, excellent fluorescent properties and facile fabrication method, the as-obtained CDs can find practical applications as cost-effective and sensitive chemo-sensors in water and food safety field.

Real-world injury patterns associated with Hybrid III sternal deflections in frontal crash tests.

PubMed

Brumbelow, Matthew L; Farmer, Charles M

2013-01-01

This study investigated the relationship between the peak sternal deflection measurements recorded by the Hybrid III 50th percentile male anthropometric test device (ATD) in frontal crash tests and injury and fatality outcomes for drivers in field crashes. ATD sternal deflection data were obtained from the Insurance Institute for Highway Safety's 64 km/h, 40 percent overlap crashworthiness evaluation tests for vehicles with seat belt crash tensioners, load limiters, and good-rated structure. The National Automotive Sampling System Crashworthiness Data System (NASS-CDS) was queried for frontal crashes of these vehicles in which the driver was restrained by a seat belt and air bag. Injury probability curves were calculated by frontal crash type using the injuries coded in NASS-CDS and peak ATD sternal deflection data. Fatality Analysis Reporting System (FARS) front-to-front crashes with exactly one driver death were also studied to determine whether the difference in measured sternal deflections for the 2 vehicles was related to the odds of fatality. For center impacts, moderate overlaps, and large overlaps in NASS-CDS, the probability of the driver sustaining an Abbreviated Injury Scale (AIS) score ≥ 3 thoracic injury, or any nonextremity AIS ≥ 3 injury, increased with increasing ATD sternal deflection measured in crash tests. For small overlaps, however, these probabilities decreased with increasing deflection. For FARS crashes, the fatally injured driver more often was in the vehicle with the lower measured deflection in crash tests (55 vs. 45%). After controlling for other factors, a 5-mm difference in measured sternal deflections between the 2 vehicles was associated with a fatality odds ratio of 0.762 for the driver in the vehicle with the greater deflection (95% confidence interval = 0.373, 1.449). Restraint systems that reduce peak Hybrid III sternal deflection in a moderate overlap crash test are beneficial in real-world crashes with similar or greater overlap but likely have a disbenefit in crashes with small overlap. This may occur because belt-force limiters employed to control deflections allow excursion that could produce contact with interior vehicle components in small overlaps, given the more oblique occupant motion and potential inboard movement of the air bag. Although based on a limited number of cases, this interpretation is supported by differences in skeletal fracture locations among drivers in crashes with different overlaps. Current restraint systems could be improved by designs that reduce sternal deflection in moderate and large overlap crashes without increasing occupant excursion in small overlap crashes.

Health information technology in primary health care in developing countries: a literature review.

PubMed Central

Tomasi, Elaine; Facchini, Luiz Augusto; Maia, Maria de Fatima Santos

2004-01-01

This paper explores the debate and initiatives concerning the use of information technology (IT) in primary health care in developing countries. The literature from 1992-2002 was identified from searches of the MEDLINE, Latin American and Caribbean Health Science Literature Database (LILACS), Cochrane Library and Web of Science databases. The search identified 884 references, 350 of which were classified according to the scheme described by the Pan American Health Organization (PAHO). For the analysis of advantages, problems and perspectives of IT applications and systems, 52 articles were selected according to their potential contribution to the primary health-care processes in non-developed countries. These included: 10 on electronic patient registries (EPR), 22 on process and programmatic action evaluation and management systems (PPAEM) and 20 on clinical decision-support systems (CDS). The main advantages, limitations and perspectives are discussed. PMID:15640923

Carbon dots-decorated multiwalled carbon nanotubes nanocomposites as a high-performance electrochemical sensor for detection of H2O2 in living cells.

PubMed

Bai, Jing; Sun, Chunhe; Jiang, Xiue

2016-07-01

A novel enzyme-free hydrogen peroxide sensor composed of carbon dots (CDs) and multi-walled carbon nanotubes (MWCNTs) was prepared. It was found that the carbon dots-decorated multi-walled carbon nanotubes nanocomposites (CDs/MWCNTs) modified glassy carbon (GC) electrode (CDs/MWCNTs/GCE) exhibited a significant synergistic electrocatalytic activity towards hydrogen peroxide reduction as compared to carbon dots or multi-walled carbon nanotubes alone, and the CDs/MWCNTs/GCE has shown a low detection limit as well as excellent stability, selectivity, and reproducibility. These remarkable analytical advantages enable the practical application of CDs/MWCNTs/GCE for the real-time tracking of hydrogen peroxide (H2O2) released from human cervical cancer cells with satisfactory results. The enhanced electrochemical activity can be assigned to the edge plane-like defective sites and lattice oxygen in the CDs/MWCNTs nanocomposites due to the small amount of decoration of carbon dots on the multi-walled carbon nanotubes. Based on a facile preparation method and with good electrochemical properties, the CDs/MWCNTs nanocomposites represent a new class of carbon electrode for electrochemical sensor applications. Graphical Abstract CDs/MWCNTs exhibited good electrocatalytic activity and stability to H2O2 reduction and can be used for real-time detection of H2O2 released from living cells.

One-pot synthesis and lubricity of fluorescent carbon dots applied on PCL-PEG-PCL hydrogel.

PubMed

Guo, Junde; Mei, Tangjie; Li, Yue; Hafezi, Mahshid; Lu, Hailin; Li, Jianhui; Dong, Guangneng

2018-06-12

This work presents a method for one-pot synthesis of N-doped nanometer-size carbon dots, which can be assembled with thermosensitive poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL, PCEC) hydrogel to achieve slow-release lubricity. The typical property of this green production was studied by fourier transform infrared (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscope (TEM). The photoluminescence of composite PCEC/CDs hydrogel and its released solutions were characterized by ultraviolet spectrum, and the rheological properties were tested by rotary rheometer. Tribological performance of the released solution from composite PCEC/CDs hydrogel was obtained to compare with PBS and pure CDs solution. The experimental results reveal that the CDs contain the chemical groups of N-H, C-OH/C-O-C and -COOH, etc. In addition, the diameter of the CDs is in the range of 6~8 nm. The phase transition behavior of PCEC/CDs hydrogel can be still kept and its viscoelasticity hydrogel is improved by approximatively 7%. Furthermore, friction coefficient of the released solution from composite PCEC/CDs hydrogel decreases by about 70% than that of PBS. Besides, the wear condition can be improved by a lubricating transfer film formed by released CDs. This novel strategy for slow-release application is valuable for drug delivery and bio-tribology.

Effect of preparation methods and doping on the structural and tunable emissions of CdS

NASA Astrophysics Data System (ADS)

Mohamed, Mohamed Bakr; Abdel-Kader, M. H.; Alhazime, Ali A.; Almarashi, Jamal Q. M.

2018-03-01

Fe, Mn and Mg doped CdS samples were prepared by thermolysis method in air and under flow of nitrogen. Structural, compositional and optical properties of the prepared samples were investigated using x-ray powder diffraction (XRD), scanning electron microscope (SEM/EDS mapping), Fourier transform infrared red (FTIR), UV-vis absorption and photoluminescence (PL) spectroscopes. Rietveld refinement of x-ray data showed that all the undoped and doped CdS samples prepared in air and under flow of nitrogen have both cubic and hexagonal structures. The percentages of hexagonal and cubic phases for all prepared samples were determined. The crystallite size increased for CdS prepared under flow of N2 compared with the sample prepared in air. The energy gap of all the samples was calculated using UV data. The intensity of PL emission changed according to the method of preparation and the kind of doping elements. PL emission revealed a blue shift for CdS prepared in air compared with CdS prepared under flow of nitrogen; also all doped samples showed a red shift of PL spectra compared with undoped samples. Undoped and doped CdS with Fe and Mg samples emitted violet and blue sub-spectra. Mn doped CdS prepared in air revealed violet, blue and yellow sub-spectra, while the sample prepared under flow of N2 emitted violet, blue and green sub-spectra.

Combination of counterpropagation artificial neural networks and antioxidant activities for comprehensive evaluation of associated-extraction efficiency of various cyclodextrins in the traditional Chinese formula Xue-Zhi-Ning.

PubMed

Sun, Lili; Yang, Jianwen; Wang, Meng; Zhang, Huijie; Liu, Yanan; Ren, Xiaoliang; Qi, Aidi

2015-11-10

Xue-Zhi-Ning (XZN) is a widely used traditional Chinese medicine formula to treat hyperlipidemia. Recently, cyclodextrins (CDs) have been extensively used to minimize problems relative to medicine bioavailability, such as low solubility and poor stability. The objective of this study was to determine the associated-extraction efficiency of various CDs in XZN. Three various type CDs were evaluated, including native CDs (α-CD, β-CD), hydrophilic CD derivatives (HP-β-CD and Me-β-CD), and ionic CD derivatives (SBE-β-CD and CM-β-CD). An ultra high-performance liquid chromatography (UHPLC) fingerprint was applied to determine the components in CD extracts and original aqueous extract (OAE). A counterpropagation artificial neural network (CP-ANN) was used to analyze the components in different extracts and compare the selective extraction of various CDs. Extraction efficiencies of the various CDs in terms of extracted components follow the ranking, ionic CD derivatives>hydrophilic CD derivatives>native CDs>OAE. Besides, different types of CDs have their own selective extraction and ionic CD derivatives present the strongest associated-extraction efficiency. Antioxidant potentials of various extracts were evaluated by determining the inhibition of spontaneous, H2O2-induced, CCl4-induced and Fe(2+)/ascorbic acid-induced lipid peroxidation (LPO) and analyzing the scavenging capacity for DPPH and hydroxyl radicals. The order of extraction efficiencies of the various CDs relative to antioxidant activities is as follows: SBE-β-CD>CM-β-CD>HP-β-CD>Me-β-CD>β-CD>α-CD. It can be demonstrated that all of the CDs studied increase the extraction efficiency and that ionic CD derivatives (SBE-β-CD and CM-β-CD) present the highest extraction capability in terms of amount extracted and antioxidant activities of extracts. Copyright © 2015 Elsevier B.V. All rights reserved.

CdS-pillared CoAl-layered double hydroxide nanosheets with superior photocatalytic activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qiu, Yanqiang; Lin, Bizhou, E-mail: bzlin@hqu.edu.cn; Jia, Fangcao

Graphical abstract: - Highlights: • CdS nanocrystals were intercalated into CoAl-LDH interlayer. • The nanohybrid display superior visible-light photocatalytic activity. • A photoexcitation model for the pillared heterostructured system was proposed. - Abstract: A new nanohybrid was synthesized by mixing the positively charged 2D nanosheets of CoAl-layered double hydroxide (CoAl-LDH) and the negatively charged CdS nanosol suspensions. It was revealed that the CdS nanoparticles were intercalated into the interlayer region of CoAl-LDH with a spacing of 2.62 nm. The obtained nanohybrid exhibited a mesoporous texture with an expanded specific surface area of 62 m{sup 2} g{sup −1} and a superiormore » photocatalytic activity in the degradation of acid red with a reaction constant of 1.26 × 10{sup −2} min{sup −1} under visible-light radiation, which is more than 2 times those of his parents CoAl-LDH and CdS.« less

Induction of long-lived room temperature phosphorescence of carbon dots by water in hydrogen-bonded matrices.

PubMed

Li, Qijun; Zhou, Ming; Yang, Mingyang; Yang, Qingfeng; Zhang, Zhixun; Shi, Jing

2018-02-21

Phosphorescence shows great potential for application in bioimaging and ion detection because of its long-lived luminescence and high signal-to-noise ratio, but establishing phosphorescence emission in aqueous environments remains a challenge. Herein, we present a general design strategy that effectively promotes phosphorescence by utilising water molecules to construct hydrogen-bonded networks between carbon dots (CDs) and cyanuric acid (CA). Interestingly, water molecules not only cause no phosphorescence quenching but also greatly enhance the phosphorescence emission. This enhancement behaviour can be explained by the fact that the highly ordered bound water on the CA particle surface can construct robust bridge-like hydrogen-bonded networks between the CDs and CA, which not only effectively rigidifies the C=O bonds of the CDs but also greatly enhances the rigidity of the entire system. In addition, the CD-CA suspension exhibits a high phosphorescence lifetime (687 ms) and is successfully applied in ion detection based on its visible phosphorescence.

Localized surface plasmon and exciton interaction in silver-coated cadmium sulphide quantum dots

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghosh, P.; Rustagi, K. C.; Vasa, P.

2015-05-15

Localized surface plasmon and exciton coupling has been investigated on colloidal solutions of silver-coated CdS nanoparticles (NPs), synthesized by gamma irradiation. Two broad photoluminescence (PL) bands (blue/red) corresponding to band to band and defect state transitions have been observed for the bare and coated samples. In case of bare CdS NPs, the intensity of the red PL peak is about ten times higher than the blue PL peak intensity. However, on coating the CdS NPs with silver, the peak intensity of the blue PL band gets enhanced and becomes equal to that of the red PL band. High-resolution transmission electronmore » microscopic (HRTEM) images adequately demonstrate size distribution of these metal/semiconductor nanocomposites. UV-Vis absorption studies show quantum confinement effect in these semiconductor quantum dot (SQD) systems. Absorption spectrum of silver-coated SQDs shows signature of surface plasmon-exciton coupling which has been theoretically verified.« less

A CCD-based reader combined with CdS quantum dot-labeled lateral flow strips for ultrasensitive quantitative detection of CagA

NASA Astrophysics Data System (ADS)

Gui, Chen; Wang, Kan; Li, Chao; Dai, Xuan; Cui, Daxiang

2014-02-01

Immunochromatographic assays are widely used to detect many analytes. CagA is proved to be associated closely with initiation of gastric carcinoma. Here, we reported that a charge-coupled device (CCD)-based test strip reader combined with CdS quantum dot-labeled lateral flow strips for quantitative detection of CagA was developed, which used 365-nm ultraviolet LED as the excitation light source, and captured the test strip images through an acquisition module. Then, the captured image was transferred to the computer and was processed by a software system. A revised weighted threshold histogram equalization (WTHE) image processing algorithm was applied to analyze the result. CdS quantum dot-labeled lateral flow strips for detection of CagA were prepared. One hundred sera samples from clinical patients with gastric cancer and healthy people were prepared for detection, which demonstrated that the device could realize rapid, stable, and point-of-care detection, with a sensitivity of 20 pg/mL.

Clinical Assistant Diagnosis for Electronic Medical Record Based on Convolutional Neural Network.

PubMed

Yang, Zhongliang; Huang, Yongfeng; Jiang, Yiran; Sun, Yuxi; Zhang, Yu-Jin; Luo, Pengcheng

2018-04-20

Automatically extracting useful information from electronic medical records along with conducting disease diagnoses is a promising task for both clinical decision support(CDS) and neural language processing(NLP). Most of the existing systems are based on artificially constructed knowledge bases, and then auxiliary diagnosis is done by rule matching. In this study, we present a clinical intelligent decision approach based on Convolutional Neural Networks(CNN), which can automatically extract high-level semantic information of electronic medical records and then perform automatic diagnosis without artificial construction of rules or knowledge bases. We use collected 18,590 copies of the real-world clinical electronic medical records to train and test the proposed model. Experimental results show that the proposed model can achieve 98.67% accuracy and 96.02% recall, which strongly supports that using convolutional neural network to automatically learn high-level semantic features of electronic medical records and then conduct assist diagnosis is feasible and effective.

Nitrogen and Phosphorus Co-Doped Carbon Nanodots as a Novel Fluorescent Probe for Highly Sensitive Detection of Fe(3+) in Human Serum and Living Cells.

PubMed

Shi, Bingfang; Su, Yubin; Zhang, Liangliang; Huang, Mengjiao; Liu, Rongjun; Zhao, Shulin

2016-05-04

Chemical doping with heteroatoms can effectively modulate physicochemical and photochemical properties of carbon dots (CDs). However, the development of multi heteroatoms codoped carbon nanodots is still in its early stage. In this work, a facile hydrothermal synthesis strategy was applied to synthesize multi heteroatoms (nitrogen and phosphorus) codoped carbon nanodots (N,P-CDs) using glucose as carbon source, and ammonia, phosphoric acid as dopant, respectively. Compared with CDs, the multi heteroatoms doped CDs resulted in dramatic improvement in the electronic characteristics and surface chemical activities. Therefore, the N,P-CDs prepared as described above exhibited a strong blue emission and a sensitive response to Fe(3+). The N,P-CDs based fluorescent sensor was then applied to sensitively determine Fe(3+) with a detection limit of 1.8 nM. Notably, the prepared N,P-CDs possessed negligible cytotoxicity, excellent biocompatibility, and high photostability. It was also applied for label-free detection of Fe(3+) in complex biological samples and the fluorescence imaging of intracellular Fe(3+), which indicated its potential applications in clinical diagnosis and other biologically related study.

Morphology, structure and optical properties of hydrothermally synthesized CeO2/CdS nanocomposites

NASA Astrophysics Data System (ADS)

Mohanty, Biswajyoti; Nayak, J.

2018-04-01

CeO2/CdS nanocomposites were synthesized using a two-step hydrothermal technique. The effects of precursor concentration on the optical and structural properties of the CeO2/CdS nanoparticles were systematically studied. The morphology, composition and the structure of the CeO2/CdS nanocomposite powder were studied by scanning electron microscopy (SEM), energy dispersive X-ray spectrum analysis (EDXA) and X-ray diffraction (XRD), respectively. The optical properties of CeO2/CdS nanocomposites were studied by UV-vis absorption and photoluminescence (PL) spectroscopy. The optical band gaps of the CeO2/CdS nanopowders ranged from 2.34 eV to 2.39 eV as estimated from the UV-vis absorption. In the room temperature photoluminescence spectrum of CeO2/CdS nanopowder, a strong blue emission band was observed at 400 nm. Since the powder shows strong visible luminescence, it may be used as a blue phosphor in future. The original article published with this DOI was submitted in error. The correct article was inadvertently left out of the original submission. This has been rectified and the correct article was published online on 16 April 2018.

Ratiometric, visual, dual-signal fluorescent sensing and imaging of pH/copper ions in real samples based on carbon dots-fluorescein isothiocyanate composites.

PubMed

Zhu, Xinxin; Jin, Hui; Gao, Cuili; Gui, Rijun; Wang, Zonghua

2017-01-01

In this article, a facile aqueous synthesis of carbon dots (CDs) was developed by using natural kelp as a new carbon source. Through hydrothermal carbonization of kelp juice, fluorescent CDs were prepared and the CDs' surface was modified with polyethylenimine (PEI). The PEI-modified CDs were conjugated with fluorescein isothiocyanate (FITC) to fabricate CDs-FITC composites. To exploit broad applications, the CDs-FITC composites were developed as fluorescent sensing or imaging platforms of pH and Cu 2+ . Analytical performances of the composites-based fluorescence (FL) sensors were evaluated, including visual FL imaging of pH in glass bottle, ratiometric FL sensing of pH in yogurt samples, visual FL latent fingerprint and leaf imaging detection of [Cu 2+ ], dual-signal FL sensing of [Cu 2+ ] in yogurt and human serum samples. Experimental results from ratiometric, visual, dual-signal FL sensing and imaging applications confirmed the high feasibility, accuracy, stabilization and simplicity of CDs-FITC composites-based FL sensors for the detection of pH and Cu 2+ ions in real samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Quantum dots coupled ZnO nanowire-array panels and their photocatalytic activities.

PubMed

Liao, Yulong; Que, Wenxiu; Zhang, Jin; Zhong, Peng; Yuan, Yuan; Qiu, Xinku; Shen, Fengyu

2013-02-01

Fabrication and characterization of a heterojunction structured by CdS quantum dots@ZnO nanowire-array panels were presented. Firstly, ZnO nanowire-array panels were prepared by using a chemical bath deposition approach where wurtzite ZnO nanowires with a diameter of about 100 nm and 3 microm in length grew perpendicularly to glass substrate. Secondly, CdS quantum dots were deposited onto the surface of the ZnO nanowire-arrays by using successive ion layer absorption and reaction method, and the CdS shell/ZnO core heterojunction were thus obtained. Field emission scanning electron microscopy and transmission electron microscope were employed to characterize the morphological properties of the as-obtained CdS quantum dots@ZnO nanowire-array panels. X-ray diffraction was adopted to characterize the crystalline properties of the as-obtained CdS quantum dots@ZnO nanowire-array panels. Methyl orange was taken as a model compound to confirm the photocatalytic activities of the CdS shell/ZnO core heterojunction. Results indicate that CdS with narrow band gap not only acts as a visible-light sensitizer but also is responsible for an effective charge separation.

Enhanced photocatalytic activity of graphitic carbon nitride/cadmium sulfide heterojunctions by protonating treatment

NASA Astrophysics Data System (ADS)

Yan, Mengdie; Ma, Yushuang; Zhang, Huanhuan; Ye, Boyong; Dong, Xiaoping

2018-05-01

Highly efficient visible-light-driven protonated g-C3N4 (pg-C3N4)/CdS heterojunctions with different weight ratios of CdS were prepared by treating g-C3N4 with hydrochloric acid and using an in-situ precipitation method. The structure and morphology of heterojunctions were investigated by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectroscopy (FTIR) and nitrogen adsorption technology. The as-prepared pg-C3N4/CdS heterojunction with 50 wt% of g-C3N4 exhibited much higher photocatalytic activity for photodegradation of methyl orange (MO) than pg-C3N4, CdS and g-C3N4/CdS without protonation as well, which could be contributed to the activation of hydrochloric acid treatment and the improved electron-hole separation due to their overlapping band structure of CdS and pg-C3N4. A possible photocatalytic mechanism of the pg-C3N4/CdS heterojunctions with superoxide radical species as the main active species in photocatalysis was proposed on the basis of experimental results.

Performance Assessment of Communicable Disease Surveillance in Disasters: A Systematic Review

PubMed Central

Babaie, Javad; Ardalan, Ali; Vatandoost, Hasan; Goya, Mohammad Mehdi; Akbarisari, Ali

2015-01-01

Background: This study aimed to identify the indices and frameworks that have been used to assess the performance of communicable disease surveillance (CDS) in response to disasters and other emergencies, including infectious disease outbreaks. Method: In this systematic review, PubMed, Google Scholar, Scopus, ScienceDirect, ProQuest databases and grey literature were searched until the end of 2013. All retrieved titles were examined in accordance with inclusion criteria. Abstracts of the relevant titles were reviewed and eligible abstracts were included in a list for data abstraction. Finally, the study variables were extracted. Results: Sixteen articles and one book were found relevant to our study objectives. In these articles, 31 criteria and 35 indicators were used or suggested for the assessment/evaluation of the performance of surveillance systems in disasters. The Centers for Disease Control (CDC) updated guidelines for the evaluation of public health surveillance systems were the most widely used. Conclusion: Despite the importance of performance assessment in improving CDS in response to disasters, there is a lack of clear and accepted frameworks. There is also no agreement on the use of existing criteria and indices. The only relevant framework is the CDC guideline, which is a common framework for assessing public health surveillance systems as a whole. There is an urgent need to develop appropriate frameworks, criteria, and indices for specifically assessing the performance of CDS in response to disasters and other emergencies, including infectious diseases outbreaks. Key words: Disasters, Emergencies, Communicable Diseases, Surveillance System, Performance Assessment PMID:25774323

Enhancement of periodate-hydrogen peroxide chemiluminescence by nitrogen doped carbon dots and its application for the determination of pyrogallol and gallic acid.

PubMed

Shah, Syed Niaz Ali; Li, Haifang; Lin, Jin-Ming

2016-06-01

A new sensitized chemiluminescence (CL) was developed to broaden the analytical application of KIO4-H2O2 system. The nitrogen doped carbon dots (N-CDs) dramatically boosted the CL intensity of KIO4-H2O2 system which was further enriched by basic medium. In light of EPR analysis, free radical scavenging studies and CL spectra the detail mechanism for the enhancement was conferred in the presence of N-CDs and NaOH. The results suggested that CL of KIO4-H2O2 system in the presence and absence of N-CDs and NaOH proceeds via radical pathway. The enhanced CL was used for the determination of pyrogallol and gallic acid in range of 1.0×10(-4)-1.0×10(-7)M with 4.6×10(-8) and 6.1×10(-8)M limit of detection respectively. The relative standard deviation (RSD) at a concentration of 10(-5) for gallic acid and pyrogallol was 1.4% and 2.3% respectively (n=11). The attained results unveil that the present method is sensitive, faster, simpler and less costly compared to other methods and could be applied to determine polyphenols in real samples. Copyright © 2016 Elsevier B.V. All rights reserved.