49 CFR 40.191 - What is a refusal to take a DOT drug test, and what are the consequences?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false What is a refusal to take a DOT drug test, and... Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Drug Tests § 40.191 What is a refusal to take a DOT drug test, and what are the consequences? (a) As an employee...

75 FR 5722 - Procedures for Transportation Workplace Drug and Alcohol Testing Programs

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-04

... drugs in a DOT drug test. You must not test ``DOT specimens'' for any other drugs. (a) Marijuana... test analyte concentration analyte concentration Marijuana metabolites 50 ng/mL THCA \\1\\ 15 ng/mL...

49 CFR 40.13 - How do DOT drug and alcohol tests relate to non-DOT tests?

Code of Federal Regulations, 2010 CFR

2010-10-01

... drugs, and a laboratory is prohibited from making a DOT urine specimen available for a DNA test or other... a blood or urine specimen collected by the employee's physician or a DNA test result purporting to...

49 CFR 40.13 - How do DOT drug and alcohol tests relate to non-DOT tests?

Code of Federal Regulations, 2011 CFR

2011-10-01

... drugs, and a laboratory is prohibited from making a DOT urine specimen available for a DNA test or other... a blood or urine specimen collected by the employee's physician or a DNA test result purporting to...

49 CFR 40.13 - How do DOT drug and alcohol tests relate to non-DOT tests?

Code of Federal Regulations, 2012 CFR

2012-10-01

... drugs, and a laboratory is prohibited from making a DOT urine specimen available for a DNA test or other... a blood or urine specimen collected by the employee's physician or a DNA test result purporting to...

49 CFR 40.13 - How do DOT drug and alcohol tests relate to non-DOT tests?

Code of Federal Regulations, 2014 CFR

2014-10-01

... drugs, and a laboratory is prohibited from making a DOT urine specimen available for a DNA test or other... a blood or urine specimen collected by the employee's physician or a DNA test result purporting to...

49 CFR 40.13 - How do DOT drug and alcohol tests relate to non-DOT tests?

Code of Federal Regulations, 2013 CFR

2013-10-01

... drugs, and a laboratory is prohibited from making a DOT urine specimen available for a DNA test or other... a blood or urine specimen collected by the employee's physician or a DNA test result purporting to...

49 CFR Appendix H to Part 40 - DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form

Code of Federal Regulations, 2010 CFR

2010-10-01

..., App. H Appendix H to Part 40—DOT Drug and Alcohol Testing Management Information System (MIS) Data... 49 Transportation 1 2010-10-01 2010-10-01 false DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form H Appendix H to Part 40 Transportation Office of the Secretary...

49 CFR 40.15 - May an employer use a service agent to meet DOT drug and alcohol testing requirements?

Code of Federal Regulations, 2010 CFR

2010-10-01

... Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Employer Responsibilities § 40.15 May an employer use a service agent to meet DOT drug and alcohol testing requirements? (a... 49 Transportation 1 2010-10-01 2010-10-01 false May an employer use a service agent to meet DOT...

49 CFR Appendix H to Part 40 - DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form

Code of Federal Regulations, 2013 CFR

2013-10-01

..., App. H Appendix H to Part 40—DOT Drug and Alcohol Testing Management Information System (MIS) Data... 49 Transportation 1 2013-10-01 2013-10-01 false DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form H Appendix H to Part 40 Transportation Office of the Secretary...

49 CFR Appendix H to Part 40 - DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form

Code of Federal Regulations, 2014 CFR

2014-10-01

..., App. H Appendix H to Part 40—DOT Drug and Alcohol Testing Management Information System (MIS) Data... 49 Transportation 1 2014-10-01 2014-10-01 false DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form H Appendix H to Part 40 Transportation Office of the Secretary...

49 CFR Appendix H to Part 40 - DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form

Code of Federal Regulations, 2012 CFR

2012-10-01

..., App. H Appendix H to Part 40—DOT Drug and Alcohol Testing Management Information System (MIS) Data... 49 Transportation 1 2012-10-01 2012-10-01 false DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form H Appendix H to Part 40 Transportation Office of the Secretary...

49 CFR Appendix H to Part 40 - DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form

Code of Federal Regulations, 2011 CFR

2011-10-01

..., App. H Appendix H to Part 40—DOT Drug and Alcohol Testing Management Information System (MIS) Data... 49 Transportation 1 2011-10-01 2011-10-01 false DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form H Appendix H to Part 40 Transportation Office of the Secretary...

49 CFR 40.123 - What are the MRO's responsibilities in the DOT drug testing program?

Code of Federal Regulations, 2014 CFR

2014-10-01

... drug testing program? 40.123 Section 40.123 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Medical Review Officers and the Verification Process § 40.123 What are the MRO's responsibilities in the DOT drug testing program? As an MRO...

49 CFR 40.123 - What are the MRO's responsibilities in the DOT drug testing program?

Code of Federal Regulations, 2012 CFR

2012-10-01

... drug testing program? 40.123 Section 40.123 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Medical Review Officers and the Verification Process § 40.123 What are the MRO's responsibilities in the DOT drug testing program? As an MRO...

49 CFR 40.123 - What are the MRO's responsibilities in the DOT drug testing program?

Code of Federal Regulations, 2013 CFR

2013-10-01

... drug testing program? 40.123 Section 40.123 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Medical Review Officers and the Verification Process § 40.123 What are the MRO's responsibilities in the DOT drug testing program? As an MRO...

49 CFR 40.123 - What are the MRO's responsibilities in the DOT drug testing program?

Code of Federal Regulations, 2010 CFR

2010-10-01

... drug testing program? 40.123 Section 40.123 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Medical Review Officers and the Verification Process § 40.123 What are the MRO's responsibilities in the DOT drug testing program? As an MRO...

49 CFR 40.123 - What are the MRO's responsibilities in the DOT drug testing program?

Code of Federal Regulations, 2011 CFR

2011-10-01

... drug testing program? 40.123 Section 40.123 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Medical Review Officers and the Verification Process § 40.123 What are the MRO's responsibilities in the DOT drug testing program? As an MRO...

49 CFR 40.45 - What form is used to document a DOT urine collection?

Code of Federal Regulations, 2012 CFR

2012-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Collection Sites, Forms, Equipment and Supplies Used... Federal Drug Testing Custody and Control Form (CCF) must be used to document every urine collection required by the DOT drug testing program. The CCF must be a five-part carbonless manifold form. You may...

49 CFR 40.45 - What form is used to document a DOT urine collection?

Code of Federal Regulations, 2013 CFR

2013-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Collection Sites, Forms, Equipment and Supplies Used... Federal Drug Testing Custody and Control Form (CCF) must be used to document every urine collection required by the DOT drug testing program. The CCF must be a five-part carbonless manifold form. You may...

49 CFR 40.45 - What form is used to document a DOT urine collection?

Code of Federal Regulations, 2014 CFR

2014-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Collection Sites, Forms, Equipment and Supplies Used... Federal Drug Testing Custody and Control Form (CCF) must be used to document every urine collection required by the DOT drug testing program. The CCF must be a five-part carbonless manifold form. You may...

46 CFR 16.203 - Employer, MRO, and SAP responsibilities.

Code of Federal Regulations, 2010 CFR

2010-10-01

... and among employers and service agents concerning the implementation of DOT drug testing requirements... DOT agency drug testing regulations. Compliance with these provisions is a material term of all such... CHEMICAL TESTING Required Chemical Testing § 16.203 Employer, MRO, and SAP responsibilities. (a) Employers...

46 CFR 16.203 - Employer, MRO, and SAP responsibilities.

Code of Federal Regulations, 2011 CFR

2011-10-01

... and among employers and service agents concerning the implementation of DOT drug testing requirements... DOT agency drug testing regulations. Compliance with these provisions is a material term of all such... CHEMICAL TESTING Required Chemical Testing § 16.203 Employer, MRO, and SAP responsibilities. (a) Employers...

46 CFR 16.203 - Employer, MRO, and SAP responsibilities.

Code of Federal Regulations, 2014 CFR

2014-10-01

... and among employers and service agents concerning the implementation of DOT drug testing requirements... DOT agency drug testing regulations. Compliance with these provisions is a material term of all such... CHEMICAL TESTING Required Chemical Testing § 16.203 Employer, MRO, and SAP responsibilities. (a) Employers...

46 CFR 16.203 - Employer, MRO, and SAP responsibilities.

Code of Federal Regulations, 2012 CFR

2012-10-01

... and among employers and service agents concerning the implementation of DOT drug testing requirements... DOT agency drug testing regulations. Compliance with these provisions is a material term of all such... CHEMICAL TESTING Required Chemical Testing § 16.203 Employer, MRO, and SAP responsibilities. (a) Employers...

46 CFR 16.203 - Employer, MRO, and SAP responsibilities.

Code of Federal Regulations, 2013 CFR

2013-10-01

... and among employers and service agents concerning the implementation of DOT drug testing requirements... DOT agency drug testing regulations. Compliance with these provisions is a material term of all such... CHEMICAL TESTING Required Chemical Testing § 16.203 Employer, MRO, and SAP responsibilities. (a) Employers...

49 CFR 40.211 - Who conducts DOT alcohol tests?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 1 2011-10-01 2011-10-01 false Who conducts DOT alcohol tests? 40.211 Section 40... DRUG AND ALCOHOL TESTING PROGRAMS Alcohol Testing Personnel § 40.211 Who conducts DOT alcohol tests? (a) Screening test technicians (STTs) and breath alcohol technicians (BATs) meeting their respective...

49 CFR 40.211 - Who conducts DOT alcohol tests?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Who conducts DOT alcohol tests? 40.211 Section 40... DRUG AND ALCOHOL TESTING PROGRAMS Alcohol Testing Personnel § 40.211 Who conducts DOT alcohol tests? (a) Screening test technicians (STTs) and breath alcohol technicians (BATs) meeting their respective...

49 CFR 40.211 - Who conducts DOT alcohol tests?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 1 2013-10-01 2013-10-01 false Who conducts DOT alcohol tests? 40.211 Section 40.211 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Alcohol Testing Personnel § 40.211 Who conducts DOT alcohol tests? (a) Screening test technicians (STTs) and breat...

75 FR 59105 - Procedures for Transportation Workplace Drug and Alcohol Testing Programs: Federal Drug Testing...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-27

... (the checkmark can pre-printed in the appropriate box on the CCF at Step 1-D). (h) Test reason, as appropriate: Pre-employment; Random; Reasonable Suspicion/Reasonable Cause; Post-Accident; Return-to-Duty; and... reason (e.g., random test, post-accident test) and DOT Agency (e.g., check DOT and FMCSA) as for the...

49 CFR 40.389 - What factors may the Director consider?

Code of Federal Regulations, 2012 CFR

2012-10-01

... WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Public Interest Exclusions § 40.389 What factors may the... DOT agency regulation, the degree to which the noncompliance affects matters common to the DOT drug and alcohol testing program; (g) Other factors appropriate to the circumstances of the case. ...

49 CFR 40.107 - Who may inspect laboratories?

Code of Federal Regulations, 2010 CFR

2010-10-01

... DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.107 Who may inspect laboratories? As a...-regulated employer that contracts with the laboratory for drug testing under the DOT drug testing program...

49 CFR 40.107 - Who may inspect laboratories?

Code of Federal Regulations, 2012 CFR

2012-10-01

... DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.107 Who may inspect laboratories? As a...-regulated employer that contracts with the laboratory for drug testing under the DOT drug testing program...

49 CFR 40.107 - Who may inspect laboratories?

Code of Federal Regulations, 2014 CFR

2014-10-01

... DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.107 Who may inspect laboratories? As a...-regulated employer that contracts with the laboratory for drug testing under the DOT drug testing program...

49 CFR 40.107 - Who may inspect laboratories?

Code of Federal Regulations, 2013 CFR

2013-10-01

... DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.107 Who may inspect laboratories? As a...-regulated employer that contracts with the laboratory for drug testing under the DOT drug testing program...

49 CFR 40.107 - Who may inspect laboratories?

Code of Federal Regulations, 2011 CFR

2011-10-01

... DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.107 Who may inspect laboratories? As a...-regulated employer that contracts with the laboratory for drug testing under the DOT drug testing program...

49 CFR 40.85 - What drugs do laboratories test for?

Code of Federal Regulations, 2013 CFR

2013-10-01

... WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.85 What drugs do laboratories test for? As a laboratory, you must test for the following five drugs or classes of drugs in a DOT drug... 49 Transportation 1 2013-10-01 2013-10-01 false What drugs do laboratories test for? 40.85 Section...

49 CFR 40.85 - What drugs do laboratories test for?

Code of Federal Regulations, 2014 CFR

2014-10-01

... WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.85 What drugs do laboratories test for? As a laboratory, you must test for the following five drugs or classes of drugs in a DOT drug... 49 Transportation 1 2014-10-01 2014-10-01 false What drugs do laboratories test for? 40.85 Section...

49 CFR 40.85 - What drugs do laboratories test for?

Code of Federal Regulations, 2011 CFR

2011-10-01

... WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.85 What drugs do laboratories test for? As a laboratory, you must test for the following five drugs or classes of drugs in a DOT drug... 49 Transportation 1 2011-10-01 2011-10-01 false What drugs do laboratories test for? 40.85 Section...

49 CFR 40.85 - What drugs do laboratories test for?

Code of Federal Regulations, 2012 CFR

2012-10-01

... WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.85 What drugs do laboratories test for? As a laboratory, you must test for the following five drugs or classes of drugs in a DOT drug... 49 Transportation 1 2012-10-01 2012-10-01 false What drugs do laboratories test for? 40.85 Section...

49 CFR 40.85 - What drugs do laboratories test for?

Code of Federal Regulations, 2010 CFR

2010-10-01

... WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.85 What drugs do laboratories test for? As a laboratory, you must test for the following five drugs or classes of drugs in a DOT drug... 49 Transportation 1 2010-10-01 2010-10-01 false What drugs do laboratories test for? 40.85 Section...

49 CFR 40.273 - What is the effect of a cancelled alcohol test?

Code of Federal Regulations, 2010 CFR

2010-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Alcohol Testing § 40.273 What is the... cancellation. (d) A cancelled DOT test does not provide a valid basis for an employer to conduct a non-DOT test...

49 CFR 199.117 - Recordkeeping.

Code of Federal Regulations, 2011 CFR

2011-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY DRUG AND ALCOHOL TESTING Drug Testing... provided by DOT Procedures. Statistical data related to drug testing and rehabilitation that is not name... employee drug test that indicate a verified positive result, records that demonstrate compliance with the...

49 CFR 199.117 - Recordkeeping.

Code of Federal Regulations, 2013 CFR

2013-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY DRUG AND ALCOHOL TESTING Drug Testing... provided by DOT Procedures. Statistical data related to drug testing and rehabilitation that is not name... employee drug test that indicate a verified positive result, records that demonstrate compliance with the...

49 CFR 199.117 - Recordkeeping.

Code of Federal Regulations, 2012 CFR

2012-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY DRUG AND ALCOHOL TESTING Drug Testing... provided by DOT Procedures. Statistical data related to drug testing and rehabilitation that is not name... employee drug test that indicate a verified positive result, records that demonstrate compliance with the...

49 CFR 199.117 - Recordkeeping.

Code of Federal Regulations, 2010 CFR

2010-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY DRUG AND ALCOHOL TESTING Drug Testing... provided by DOT Procedures. Statistical data related to drug testing and rehabilitation that is not name... employee drug test that indicate a verified positive result, records that demonstrate compliance with the...

49 CFR 199.117 - Recordkeeping.

Code of Federal Regulations, 2014 CFR

2014-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY DRUG AND ALCOHOL TESTING Drug Testing... provided by DOT Procedures. Statistical data related to drug testing and rehabilitation that is not name... employee drug test that indicate a verified positive result, records that demonstrate compliance with the...

78 FR 41974 - Agency Information Collection Activities: Requests for Comments; Clearance of a Renewed Approval...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-12

...The Department of Transportation (DOT) invites public comments about our intention to request the Office of Management and Budget (OMB) approval to renew an information collection. The collection involves Transportation Drug and Alcohol Testing. The information to be collected will be used to document tests conducted and actions taken to ensure safety in the workplace and/or is necessary because under the Omnibus Transportation Employee Testing Act of 1991, DOT is required to implement a drug and alcohol testing program in various transportation- related industries. DOT is required to publish this notice in the Federal Register in accordance with the Paperwork Reduction Act of 1995, Public Law 104-13.

49 CFR 40.389 - What factors may the Director consider?

Code of Federal Regulations, 2013 CFR

2013-10-01

... WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Public Interest Exclusions § 40.389 What factors may the... duration of the noncompliance; (c) Whether there is a pattern or prior history of noncompliance; (d... DOT agency regulation, the degree to which the noncompliance affects matters common to the DOT drug...

49 CFR 40.27 - May an employer require an employee to sign a consent or release in connection with the DOT drug...

Code of Federal Regulations, 2010 CFR

2010-10-01

... TESTING PROGRAMS Employer Responsibilities § 40.27 May an employer require an employee to sign a consent or release in connection with the DOT drug and alcohol testing program? No, as an employer, you must... 49 Transportation 1 2010-10-01 2010-10-01 false May an employer require an employee to sign a...

49 CFR 40.33 - What training requirements must a collector meet?

Code of Federal Regulations, 2012 CFR

2012-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Urine Collection Personnel § 40.33 What training... about this part, the current “DOT Urine Specimen Collection Procedures Guidelines,” and DOT agency... changes to these materials. The DOT Urine Specimen Collection Procedures Guidelines document is available...

49 CFR 40.33 - What training requirements must a collector meet?

Code of Federal Regulations, 2013 CFR

2013-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Urine Collection Personnel § 40.33 What training... about this part, the current “DOT Urine Specimen Collection Procedures Guidelines,” and DOT agency... changes to these materials. The DOT Urine Specimen Collection Procedures Guidelines document is available...

49 CFR 40.33 - What training requirements must a collector meet?

Code of Federal Regulations, 2011 CFR

2011-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Urine Collection Personnel § 40.33 What training... about this part, the current “DOT Urine Specimen Collection Procedures Guidelines,” and DOT agency... changes to these materials. The DOT Urine Specimen Collection Procedures Guidelines document is available...

49 CFR 40.33 - What training requirements must a collector meet?

Code of Federal Regulations, 2010 CFR

2010-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Urine Collection Personnel § 40.33 What training... about this part, the current “DOT Urine Specimen Collection Procedures Guidelines,” and DOT agency... changes to these materials. The DOT Urine Specimen Collection Procedures Guidelines document is available...

49 CFR 40.33 - What training requirements must a collector meet?

Code of Federal Regulations, 2014 CFR

2014-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Urine Collection Personnel § 40.33 What training... about this part, the current “DOT Urine Specimen Collection Procedures Guidelines,” and DOT agency... changes to these materials. The DOT Urine Specimen Collection Procedures Guidelines document is available...

75 FR 8528 - Procedures for Transportation Workplace Drug and Alcohol Testing Programs

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-25

... updated U.S. DOT Alcohol Testing Form (ATF) and the Management Information System (MIS) Data Collection... included a revised U.S. DOT Alcohol Testing Form (ATF) and the Management Information System (MIS) Data...) and Management Information System (MIS) form Federal Register [73 FR 14300] and [73 FR 33140]. There...

49 CFR 199.5 - DOT procedures.

Code of Federal Regulations, 2010 CFR

2010-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY DRUG AND ALCOHOL TESTING General § 199.5... to the requirements of this part and DOT Procedures. Terms and concepts used in this part have the...

49 CFR 40.103 - What are the requirements for submitting blind specimens to a laboratory?

Code of Federal Regulations, 2013 CFR

2013-10-01

... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.103... specimens you submit must be negative (i.e., containing no drugs, nor adulterated or substituted). Approximately 15 percent must be positive for one or more of the five drugs involved in DOT tests, and...

49 CFR 40.103 - What are the requirements for submitting blind specimens to a laboratory?

Code of Federal Regulations, 2011 CFR

2011-10-01

... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.103... specimens you submit must be negative (i.e., containing no drugs, nor adulterated or substituted). Approximately 15 percent must be positive for one or more of the five drugs involved in DOT tests, and...

49 CFR 40.103 - What are the requirements for submitting blind specimens to a laboratory?

Code of Federal Regulations, 2014 CFR

2014-10-01

... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.103... specimens you submit must be negative (i.e., containing no drugs, nor adulterated or substituted). Approximately 15 percent must be positive for one or more of the five drugs involved in DOT tests, and...

49 CFR 40.103 - What are the requirements for submitting blind specimens to a laboratory?

Code of Federal Regulations, 2012 CFR

2012-10-01

... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.103... specimens you submit must be negative (i.e., containing no drugs, nor adulterated or substituted). Approximately 15 percent must be positive for one or more of the five drugs involved in DOT tests, and...

49 CFR 40.103 - What are the requirements for submitting blind specimens to a laboratory?

Code of Federal Regulations, 2010 CFR

2010-10-01

... PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.103... specimens you submit must be negative (i.e., containing no drugs, nor adulterated or substituted). Approximately 15 percent must be positive for one or more of the five drugs involved in DOT tests, and...

Detection and management of drug-resistant tuberculosis in HIV-infected patients from lower income countries

PubMed Central

Ballif, Marie; Nhandu, Venerandah; Wood, Robin; Dusingize, Jean Claude; Carter, E. Jane; Cortes, Claudia P.; McGowan, Catherine C.; Diero, Lameck; Graber, Claire; Renner, Lorna; Hawerlander, Denise; Kiertiburanakul, Sasisopin; Du, Quy Tuan; Sterling, Timothy R.; Egger, Matthias; Fenner, Lukas

2015-01-01

Setting Drug resistance threatens tuberculosis (TB) control, particularly among HIV-infected persons. Objective We surveyed antiretroviral therapy (ART) programs from lower-income countries on prevention and management of drug-resistant TB. Design We used online questionnaires to collect program-level data in 47 ART programs in Southern Africa (14), East Africa (8), West Africa (7), Central Africa (5), Latin America (7) and Asia-Pacific (6 programs) in 2012. Patient-level data were collected on 1,002 adult TB patients seen at 40 of the participating ART programs. Results Phenotypic drug susceptibility testing was available at 36 (77%) ART programs, but only used for 22% of all TB patients. Molecular drug resistance testing was available at 33 (70%) programs and used for 23% of all TB patients. Twenty ART programs (43%) provided directly observed therapy (DOT) during the whole treatment, 16 (34%) during intensive phase only and 11 (23%) did not follow DOT. Fourteen (30%) ART programs reported no access to second-line TB regimens; 18 (38%) reported TB drug shortages. Conclusions Capacity to diagnose and treat drug-resistant TB was limited across ART programs in lower income countries. DOT was not always implemented and drug supply was regularly interrupted, which may contribute to the global emergence of drug resistance. PMID:25299866

49 CFR 40.411 - What is the role of the DOT Inspector General's office?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false What is the role of the DOT Inspector General's office? 40.411 Section 40.411 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Public Interest Exclusions § 40.411 What is the role of the DOT Inspector General's office...

49 CFR 40.191 - What is a refusal to take a DOT drug test, and what are the consequences?

Code of Federal Regulations, 2011 CFR

2011-10-01

..., you have refused to take a drug test if you: (1) Fail to appear for any test (except a pre-employment... the testing site before the testing process commences (see § 40.63 (c)) for a pre-employment test is... pre-employment test is not deemed to have refused to test; (4) In the case of a directly observed or...

49 CFR 40.191 - What is a refusal to take a DOT drug test, and what are the consequences?

Code of Federal Regulations, 2013 CFR

2013-10-01

..., you have refused to take a drug test if you: (1) Fail to appear for any test (except a pre-employment... the testing site before the testing process commences (see § 40.63 (c)) for a pre-employment test is... pre-employment test is not deemed to have refused to test; (4) In the case of a directly observed or...

49 CFR 40.191 - What is a refusal to take a DOT drug test, and what are the consequences?

Code of Federal Regulations, 2012 CFR

2012-10-01

..., you have refused to take a drug test if you: (1) Fail to appear for any test (except a pre-employment... the testing site before the testing process commences (see § 40.63 (c)) for a pre-employment test is... pre-employment test is not deemed to have refused to test; (4) In the case of a directly observed or...

77 FR 72905 - Pipeline Safety: Random Drug Testing Rate; Contractor MIS Reporting; and Obtaining DAMIS Sign-In...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-06

... Drug and Alcohol Management Information System (DAMIS) to operators, but will make the user name and... DAMIS Sign-In Information AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA), DOT... testing information must be submitted for contractors performing or ready to perform covered functions...

75 FR 13009 - Procedures for Transportation Workplace Drug and Alcohol Testing Programs

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-18

... DEPARTMENT OF TRANSPORTATION Office of the Secretary 49 CFR Part 40 [Docket DOT-OST-2008-0088] RIN OST 2105-AD84 Procedures for Transportation Workplace Drug and Alcohol Testing Programs Correction In rule document 2010-3731 beginning on page 8528 in the issue of Thursday, February 25, 2010, make the...

Synthesis of novel monomeric graphene quantum dots and corresponding nanocomposite with molecularly imprinted polymer for electrochemical detection of an anticancerous ifosfamide drug.

PubMed

Bali Prasad, Bhim; Kumar, Anil; Singh, Ragini

2017-08-15

This paper reports a typical synthesis of a nanocomposite of functionalized graphene quantum dots and imprinted polymer at the surface of screen-printed carbon electrode using N-acryloyl-4-aminobenzamide, as a functional monomer, and an anticancerous drug, ifosfamide, as a print molecule (test analyte). Herein, graphene quantum dots in nanocomposite practically induced the electrocatalytic activity by lowering the oxidation overpotential of test analyte and thereby amplifying electronic transmission, without any interfacial barrier in between the film and the electrode surface. The differential pulse anodic stripping signal at functionalized graphene quantum dots based imprinted sensor was realized to be about 3- and 7-fold higher as compared to the traditionally made imprinted polymers prepared in the presence and the absence of graphene quantum dots (un-functionalized), respectively. This may be attributed to a pertinent synergism in between the positively charged functionalized graphene quantum dots in the film and the target analyte toward the enhancement of electro-conductivity of the film and thereby the electrode kinetics. In fact, the covalent attachment of graphene quantum dots with N-acryloyl-4-aminobenzamide molecules might exert an extended conjugation at their interface facilitating electro conducting to render the channelized pathways for the electron transport. The proposed sensor is practically applicable to the ultratrace evaluation of ifosfamide in real (biological/pharmaceutical) samples with detection limit as low as 0.11ngmL -1 (S/N=3), without any matrix effect, cross-reactivity, and false-positives. Copyright © 2017 Elsevier B.V. All rights reserved.

49 CFR Appendix B to Part 40 - DOT Drug Testing Semi-Annual Laboratory Report to Employers

Code of Federal Regulations, 2013 CFR

2013-10-01

.... Specimen Results Reported (total number) By Test Reason (a) Pre-employment (number) (b) Post-Accident...) Follow-up (number) (g) Type of Test Not Noted on CCF (number) 2. Specimens Reported (a) Negative (number...

49 CFR Appendix B to Part 40 - DOT Drug Testing Semi-Annual Laboratory Report to Employers

Code of Federal Regulations, 2011 CFR

2011-10-01

.... Specimen Results Reported (total number) By Test Reason (a) Pre-employment (number) (b) Post-Accident...) Follow-up (number) (g) Type of Test Not Noted on CCF (number) 2. Specimens Reported (a) Negative (number...

49 CFR Appendix B to Part 40 - DOT Drug Testing Semi-Annual Laboratory Report to Employers

Code of Federal Regulations, 2010 CFR

2010-10-01

.... Specimen Results Reported (total number) By Test Reason (a) Pre-employment (number) (b) Post-Accident...) Follow-up (number) (g) Type of Test Not Noted on CCF (number) 2. Specimens Reported (a) Negative (number...

49 CFR Appendix B to Part 40 - DOT Drug Testing Semi-Annual Laboratory Report to Employers

Code of Federal Regulations, 2014 CFR

2014-10-01

.... Specimen Results Reported (total number) By Test Reason (a) Pre-employment (number) (b) Post-Accident...) Follow-up (number) (g) Type of Test Not Noted on CCF (number) 2. Specimens Reported (a) Negative (number...

49 CFR Appendix B to Part 40 - DOT Drug Testing Semi-Annual Laboratory Report to Employers

Code of Federal Regulations, 2012 CFR

2012-10-01

.... Specimen Results Reported (total number) By Test Reason (a) Pre-employment (number) (b) Post-Accident...) Follow-up (number) (g) Type of Test Not Noted on CCF (number) 2. Specimens Reported (a) Negative (number...

Current Application of Quantum Dots (QD) in Cancer Therapy: A Review.

PubMed

Babu, Lavanya Thilak; Paira, Priyankar

2017-01-01

Semiconductor quantum dots proved themselves as efficient fluorescent probes in cancer detection and treatment. Their size, high stability, non-photobleaching and water solubility made them a unique fluorophore in place of conventional organic dyes. Newly emerged theranostic drug delivery system using quantum dots helped us in better understanding of the drug delivery mechanism inside the cells. Surface modified Quantum dots and their applications became wide in bioimaging, immunohistochemistry, tracking intracellular drug and intracellular molecules target. We have highlighted various applications of quantum dots in cancer treatment, drug delivery, flow cytometry, and theranostics. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

49 CFR 40.1 - Who does this regulation cover?

Code of Federal Regulations, 2013 CFR

2013-10-01

... parties who conduct drug and alcohol tests required by Department of Transportation (DOT) agency regulations how to conduct these tests and what procedures to use. (b) This part concerns the activities of... post-accident testing program (see 49 CFR 219.200). ...

49 CFR 40.349 - What records may a service agent receive and maintain?

Code of Federal Regulations, 2010 CFR

2010-10-01

... TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Roles and Responsibilities of Service Agents § 40.349... part, as a service agent you may receive and maintain all records concerning DOT drug and alcohol... needed for operating a drug/alcohol program (e.g., CCFs, ATFs, names of employees in random pools, random...

Detection and management of drug-resistant tuberculosis in HIV-infected patients in lower-income countries.

PubMed

Ballif, M; Nhandu, V; Wood, R; Dusingize, J C; Carter, E J; Cortes, C P; McGowan, C C; Diero, L; Graber, C; Renner, L; Hawerlander, D; Kiertiburanakul, S; Du, Q T; Sterling, T R; Egger, M; Fenner, L

2014-11-01

Drug resistance threatens tuberculosis (TB) control, particularly among human immunodeficiency virus (HIV) infected persons. To describe practices in the prevention and management of drug-resistant TB under antiretroviral therapy (ART) programs in lower-income countries. We used online questionnaires to collect program-level data on 47 ART programs in Southern Africa (n = 14), East Africa (n = 8), West Africa (n = 7), Central Africa (n = 5), Latin America (n = 7) and the Asia-Pacific (n = 6 programs) in 2012. Patient-level data were collected on 1002 adult TB patients seen at 40 of the participating ART programs. Phenotypic drug susceptibility testing (DST) was available in 36 (77%) ART programs, but was only used for 22% of all TB patients. Molecular DST was available in 33 (70%) programs and was used in 23% of all TB patients. Twenty ART programs (43%) provided directly observed therapy (DOT) during the entire course of treatment, 16 (34%) during the intensive phase only, and 11 (23%) did not follow DOT. Fourteen (30%) ART programs reported no access to second-line anti-tuberculosis regimens; 18 (38%) reported TB drug shortages. Capacity to diagnose and treat drug-resistant TB was limited across ART programs in lower-income countries. DOT was not always implemented and drug supplies were regularly interrupted, which may contribute to the global emergence of drug resistance.

78 FR 37991 - Alcohol and Controlled Substances Testing

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-25

...-0012] RIN 2132-AB09 Alcohol and Controlled Substances Testing AGENCY: Federal Transit Administration (FTA), DOT. ACTION: Final rule. SUMMARY: This final rule is issued to revise sections of the Alcohol... prior proposal because it merely incorporates recent statutory changes to FTA's drug and alcohol testing...

49 CFR 40.221 - Where does an alcohol test take place?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 1 2011-10-01 2011-10-01 false Where does an alcohol test take place? 40.221... WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Testing Sites, Forms, Equipment and Supplies Used in Alcohol Testing § 40.221 Where does an alcohol test take place? (a) A DOT alcohol test must take place at an...

Rapid diagnosis of pulmonary tuberculosis and detection of drug resistance by combined simultaneous amplification testing and reverse dot blot.

PubMed

Chen, Yiwen; Zhang, Lahong; Hong, Liquan; Luo, Xian; Chen, Juping; Tang, Leiming; Chen, Jiahuan; Liu, Xia; Chen, Zhaojun

2018-06-01

Making a correct and rapid diagnosis is essential for managing pulmonary tuberculosis (PTB), particularly multidrug-resistant tuberculosis. We aimed to evaluate the efficacy of the combination of simultaneous amplification testing (SAT) and reverse dot blot (RDB) for the rapid detection of Mycobacterium tuberculosis (MTB) and drug-resistant mutants in respiratory samples. 225 suspected PTB and 32 non-TB pulmonary disease samples were collected. All sputum samples were sent for acid-fast bacilli smear, SAT, culture and drug susceptibility testing (DST) by the BACTEC TM MGIT TM 960 system. 53 PTB samples were tested by both RDB and DNA sequencing to identify drug resistance genes and mutated sites. The SAT positive rate (64.9%) was higher than the culture positive rate (55.1%), with a coincidence rate of 83.7%. The sensitivity and specificity of SAT for diagnosing PTB were 66.7% and 100%, respectively, while those for culture were 53.9% and 84.2%, respectively. RDB has high sensitivity and specificity in identifying drug resistance genes and mutated sites. The results of RDB correlated well with those of DST and DNA sequencing, with coincidence rates of 92.5% and 98.1%, respectively. The combination of SAT and RDB is promising for rapidly detecting PTB and monitoring drug resistance in clinical laboratories. © 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.

Graphene quantum dots for cancer targeted drug delivery.

PubMed

Iannazzo, Daniela; Pistone, Alessandro; Salamò, Marina; Galvagno, Signorino; Romeo, Roberto; Giofré, Salvatore V; Branca, Caterina; Visalli, Giuseppa; Di Pietro, Angela

2017-02-25

A biocompatible and cell traceable drug delivery system Graphene Quantum Dots (GQD) based, for the targeted delivery of the DNA intercalating drug doxorubicin (DOX) to cancer cells, is here reported. Highly dispersible and water soluble GQD, synthesized by acidic oxidation and exfoliation of multi-walled carbon nanotubes (MWCNT), were covalently linked to the tumor targeting module biotin (BTN), able to efficiently recognize biotin receptors over-expressed on cancer cells and loaded with DOX. Biological test performed on A549 cells reported a very low toxicity of the synthesized carrier (GQD and GQD-BTN). In GQD-BTN-DOX treated cancer cells, the cytotoxicity was strongly dependent from cell uptake which was greater and delayed after treatment with GQD-BTN-DOX system with respect to what observed for cells treated with the same system lacking of the targeting module BTN (GQD-DOX) or with the free drug alone. A delayed nuclear internalization of the drug is reported, due to the drug detachment from the nanosystem, triggered by the acidic environment of cancer cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Carbon dots: emerging theranostic nanoarchitectures.

PubMed

Mishra, Vijay; Patil, Akshay; Thakur, Sourav; Kesharwani, Prashant

2018-06-01

Nanotechnology has gained significant interest from biomedical and analytical researchers in recent years. Carbon dots (C-dots), a new member of the carbon nanomaterial family, are spherical, nontoxic, biocompatible, and discrete particles less than 10nm in diameter. Research interest has focused on C-dots because of their ultra-compact nanosize, favorable biocompatibility, outstanding photoluminescence, superior electron transfer ability, and versatile surface engineering properties. C-dots show significant potential for use in cellular imaging, biosensing, targeted drug delivery, and other biomedical applications. Here we discuss C-dots, in terms of their physicochemical properties, fabrication techniques, toxicity issues, surface engineering and biomedical potential in drug delivery, targeting as well as bioimaging. Copyright © 2018 Elsevier Ltd. All rights reserved.

49 CFR 40.361 - What is the purpose of a public interest exclusion (PIE)?

Code of Federal Regulations, 2010 CFR

2010-10-01

... transportation employers and employees from serious noncompliance with DOT drug and alcohol testing rules, the Department's policy is to ensure that employers conduct business only with responsible service agents. (b... alcohol testing regulations, has shown that it is not currently acting in a responsible manner. (c) A PIE...

49 CFR 22.21 - Participation criteria.

Code of Federal Regulations, 2010 CFR

2010-10-01

... certification form is available at http://www.osdbu.dot.gov/financial/docs/Cert_Debarment_DOT_F_2309-1.pdf. (j... available at http://www.osdbu.dot.gov/financial/docs/Cert_Drug-Free_DOT_F_2307-1.pdf.; and (k) It must.../financial/docs/Cert_Lobbying_DOT_F_2308-1.pdf. ...

Micelle-templated, poly(lactic-co-glycolic acid) nanoparticles for hydrophobic drug delivery.

PubMed

Nabar, Gauri M; Mahajan, Kalpesh D; Calhoun, Mark A; Duong, Anthony D; Souva, Matthew S; Xu, Jihong; Czeisler, Catherine; Puduvalli, Vinay K; Otero, José Javier; Wyslouzil, Barbara E; Winter, Jessica O

2018-01-01

Poly(lactic- co -glycolic acid) (PLGA) is widely used for drug delivery because of its biocompatibility, ability to solubilize a wide variety of drugs, and tunable degradation. However, achieving sub-100 nm nanoparticles (NPs), as might be desired for delivery via the enhanced permeability and retention effect, is extremely difficult via typical top-down emulsion approaches. Here, we present a bottom-up synthesis method yielding PLGA/block copolymer hybrids (ie, "PolyDots"), consisting of hydrophobic PLGA chains entrapped within self-assembling poly(styrene- b -ethylene oxide) (PS- b -PEO) micelles. PolyDots exhibit average diameters <50 nm and lower polydispersity than conventional PLGA NPs. Drug encapsulation efficiencies of PolyDots match conventional PLGA NPs (ie, ~30%) and are greater than those obtained from PS- b -PEO micelles (ie, ~7%). Increasing the PLGA:PS- b -PEO weight ratio alters the drug release mechanism from chain relaxation to erosion controlled. PolyDots are taken up by model glioma cells via endocytotic mechanisms within 24 hours, providing a potential means for delivery to cytoplasm. PolyDots can be lyophilized with minimal change in morphology and encapsulant functionality, and can be produced at scale using electrospray. Encapsulation of PLGA within micelles provides a bottom-up route for the synthesis of sub-100 nm PLGA-based nanocarriers with enhanced stability and drug-loading capacity, and tunable drug release, suitable for potential clinical applications.

49 CFR 40.331 - To what additional parties must employers and service agents release information?

Code of Federal Regulations, 2014 CFR

2014-10-01

... employer of Commercial Motor Vehicle (CMV) drivers holding commercial driving licenses (CDLs) or as a third party administrator for owner-operator CMV drivers with CDLs, you are authorized to comply with State... DOT drug and alcohol testing rules (including positive tests and refusals) by any CMV driver holding a...

49 CFR 40.331 - To what additional parties must employers and service agents release information?

Code of Federal Regulations, 2011 CFR

2011-10-01

... employer of Commercial Motor Vehicle (CMV) drivers holding commercial driving licenses (CDLs) or as a third party administrator for owner-operator CMV drivers with CDLs, you are authorized to comply with State... DOT drug and alcohol testing rules (including positive tests and refusals) by any CMV driver holding a...

75 FR 8526 - Procedures for Transportation Workplace Drug and Alcohol Testing Programs

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-25

... regarding the interim final rule (IFR) procedures for the use of a new alcohol screening device (ASD) which... for an employer to utilize a specific ASD to conduct required DOT alcohol tests, the device must (a... model specifications, (b) be published by NHTSA in the Federal Register on their most current ASD CPL...

Multiphoton microscopy of transdermal quantum dot delivery using two photon polymerization-fabricated polymer microneedles

PubMed Central

Gittard, Shaun D; Miller, Philip R; Boehm, Ryan D; Ovsianikov, Aleksandr; Chichkov, Boris N; Heiser, Jeremy; Gordon, John; Monteiro-Riviere, Nancy A; Narayan, Roger J

2010-01-01

Due to their ability to serve as fluorophores and drug delivery vehicles, quantum dots are a powerful tool for theranostics-based clinical applications. In this study, microneedle devices for transdermal drug delivery were fabricated by means of two-photon polymerization of an acrylate-based polymer. We examined proliferation of cells on this polymer using neonatal human epidermal keratinocytes and human dermal fibroblasts. The microneedle device was used to inject quantum dots into porcine skin; imaging of the quantum dots was performed using multiphoton microscopy. PMID:21413181

Substance Testing in the Fire Service: Making Public Safety a Matter of National Policy

DTIC Science & Technology

2014-03-01

25). Leshner (1999) submits that virtually every addictive substance—be it cocaine, marijuana , methamphetamine, heroin, or nicotine— appears to...safety sensitive. The DOT test panel tests for five classifications of drugs: amphetamines, cocaine, marijuana , opiates, and phencyclidine. When the...methods are laws, political/socio-cultural, pricing of services, and individual fire departments. Marijuana has been legalized in a number of states

Effect of the Semiconductor Quantum Dot Shell Structure on Fluorescence Quenching by Acridine Ligand

NASA Astrophysics Data System (ADS)

Linkov, P. A.; Vokhmintcev, K. V.; Samokhvalov, P. S.; Laronze-Cochard, M.; Sapi, J.; Nabiev, I. R.

2018-02-01

The main line of research in cancer treatment is the development of methods for early diagnosis and targeted drug delivery to cancer cells. Fluorescent semiconductor core/shell nanocrystals of quantum dots (e.g., CdSe/ZnS) conjugated with an anticancer drug, e.g., an acridine derivative, allow real-time tracking and control of the process of the drug delivery to tumors. However, linking of acridine derivatives to a quantum dot can be accompanied by quantum dot fluorescence quenching caused by electron transfer from the quantum dot to the organic molecule. In this work, it has been shown that the structure of the shell of the quantum dot plays the decisive role in the process of photoinduced charge transfer from the quantum dot to the acridine ligand, which is responsible for fluorescence quenching. It has been shown that multicomponent ZnS/CdS/ZnS shells of CdSe cores of quantum dots, which have a relatively small thickness, make it possible to significantly suppress a decrease in the quantum yield of fluorescence of quantum dots as compared to both the classical ZnS thin shell and superthick shells of the same composition. Thus, core/multicomponent shell CdSe/ZnS/CdS/ZnS quantum dots can be used as optimal fluorescent probes for the development of systems for diagnosis and treatment of cancer with the use of anticancer compounds based on acridine derivatives.

76 FR 20804 - Agency Information Collection Activities: Requests for Comments; Clearance of a Renewed Approval...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-13

... DEPARTMENT OF TRANSPORTATION Office of the Secretary [Docket No. DOT-OST-2011-0057] Agency Information Collection Activities: Requests for Comments; Clearance of a Renewed Approval of Information Collection(s): Procedures for Transportation Workplace Drug and Alcohol Testing Programs AGENCY: Office of...

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.

‘One-pot’ synthesis of multifunctional GSH-CdTe quantum dots for targeted drug delivery

NASA Astrophysics Data System (ADS)

Chen, Xiaoqin; Tang, Yajun; Cai, Bing; Fan, Hongsong

2014-06-01

A novel quantum dots-based multifunctional nanovehicle (DOX-QD-PEG-FA) was designed for targeted drug delivery, fluorescent imaging, tracking, and cancer therapy, in which the GSH-CdTe quantum dots play a key role in imaging and drug delivery. To exert curative effects, the antineoplastic drug doxorubicin hydrochloride (DOX) was loaded on the GSH-CdTe quantum dots through a condensation reaction. Meanwhile, a polyethylene glycol (PEG) shell was introduced to wrap the DOX-QD, thus stabilizing the structure and preventing clearance and drug release during systemic circulation. To actively target cancer cells and prevent the nanovehicles from being absorbed by normal cells, the nanoparticles were further decorated with folic acid (FA), allowing them to target HeLa cells that express the FA receptor. The multifunctional DOX-QD-PEG-FA conjugates were simply prepared using the ‘one pot’ method. In vitro study demonstrated that this simple, multifunctional nanovehicle can deliver DOX to the targeted cancer cells and localize the nanoparticles. After reaching the tumor cells, the FA on the DOX-QD-PEG surface allowed folate receptor recognition and increased the drug concentration to realize a higher curative effect. This novel, multifunctional DOX-QD-PEG-FA system shows great potential for tumor imaging, targeting, and therapy.

Keys to a drug-free workplace

NASA Astrophysics Data System (ADS)

Fortuna, Joseph J.; Fortuna, Patricia B.

1997-01-01

What does it take to establish a drug free work place. Are technologies available other than urine testing for pre- employment screening and monitoring of employees. Various methods are now available to screen for illicit drug residues on items handled by individuals. The residues can be acquired from the surfaces of items such as telephones, door knobs, steering wheels, lockers, clothing, identification cards, etc. Test kits are also available for urine testing at NIDA threshold levels. Analysis of hair, saliva, and sweat is now possible. How good ar these methods and kits. What value are they to the public. What are the legal concerns facing employers. What do the screening test show. These questions and others are addressed in this paper. The authors review for the reader how drug abuse by US workers costs businesses. The paper then addresses the various aspects of the DOT regulations to determine why urine analysis (UA) is insufficient to eliminate drug abuse. The authors present applications of screening technologies in addition to UA. Finally, the authors provide a conclusion of findings and recommendations for businesses that truly want or need drug free work places.

The drink remains the same: implicit positive associations in high but not moderate or non-caffeine users.

PubMed

Stafford, Lorenzo D; Wright, Claire; Yeomans, Martin R

2010-06-01

Research has demonstrated that high, but not low caffeine users exhibit an attentional bias to caffeine related stimuli. Separately, the Implicit Association Test (IAT; Greenwald, McGhee, & Schwartz, 1998) has been used to investigate the valence of implicit cognitions to drugs with some contradictory findings, though no work has addressed this issue with respect to caffeine. Here, we examined whether attentional bias would be found in high and moderate caffeine users using a pictorial version of the dot-probe task. A second aim was to explore differences in implicit cognitions between users and non-users. Fifteen high, moderate and non-caffeine users completed a picture dot-probe, IAT, and mood questionnaire following overnight caffeine deprivation. In the IAT, results demonstrated positive associations to caffeine related words for high but not moderate or non-users. Lower ratings for calmness were evident in both groups of caffeine compared to non-users. Dot-probe findings revealed an attentional bias among moderate caffeine users and non-users but not heavy users. The observed positive implicit associations to caffeine suggest that drug acceptability is the key in such perceptions. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Micelle-templated, poly(lactic-co-glycolic acid) nanoparticles for hydrophobic drug delivery

PubMed Central

Nabar, Gauri M; Mahajan, Kalpesh D; Calhoun, Mark A; Duong, Anthony D; Souva, Matthew S; Xu, Jihong; Czeisler, Catherine; Puduvalli, Vinay K; Otero, José Javier; Wyslouzil, Barbara E; Winter, Jessica O

2018-01-01

Purpose Poly(lactic-co-glycolic acid) (PLGA) is widely used for drug delivery because of its biocompatibility, ability to solubilize a wide variety of drugs, and tunable degradation. However, achieving sub-100 nm nanoparticles (NPs), as might be desired for delivery via the enhanced permeability and retention effect, is extremely difficult via typical top-down emulsion approaches. Methods Here, we present a bottom-up synthesis method yielding PLGA/block copolymer hybrids (ie, “PolyDots”), consisting of hydrophobic PLGA chains entrapped within self-assembling poly(styrene-b-ethylene oxide) (PS-b-PEO) micelles. Results PolyDots exhibit average diameters <50 nm and lower polydispersity than conventional PLGA NPs. Drug encapsulation efficiencies of PolyDots match conventional PLGA NPs (ie, ~30%) and are greater than those obtained from PS-b-PEO micelles (ie, ~7%). Increasing the PLGA:PS-b-PEO weight ratio alters the drug release mechanism from chain relaxation to erosion controlled. PolyDots are taken up by model glioma cells via endocytotic mechanisms within 24 hours, providing a potential means for delivery to cytoplasm. PolyDots can be lyophilized with minimal change in morphology and encapsulant functionality, and can be produced at scale using electrospray. Conclusion Encapsulation of PLGA within micelles provides a bottom-up route for the synthesis of sub-100 nm PLGA-based nanocarriers with enhanced stability and drug-loading capacity, and tunable drug release, suitable for potential clinical applications. PMID:29391794

Cost-effectiveness of treating multidrug-resistant tuberculosis.

PubMed

Resch, Stephen C; Salomon, Joshua A; Murray, Megan; Weinstein, Milton C

2006-07-01

Despite the existence of effective drug treatments, tuberculosis (TB) causes 2 million deaths annually worldwide. Effective treatment is complicated by multidrug-resistant TB (MDR TB) strains that respond only to second-line drugs. We projected the health benefits and cost-effectiveness of using drug susceptibility testing and second-line drugs in a lower-middle-income setting with high levels of MDR TB. We developed a dynamic state-transition model of TB. In a base case analysis, the model was calibrated to approximate the TB epidemic in Peru, a setting with a smear-positive TB incidence of 120 per 100,000 and 4.5% MDR TB among prevalent cases. Secondary analyses considered other settings. The following strategies were evaluated: first-line drugs administered under directly observed therapy (DOTS), locally standardized second-line drugs for previously treated cases (STR1), locally standardized second-line drugs for previously treated cases with test-confirmed MDR TB (STR2), comprehensive drug susceptibility testing and individualized treatment for previously treated cases (ITR1), and comprehensive drug susceptibility testing and individualized treatment for all cases (ITR2). Outcomes were costs per TB death averted and costs per quality-adjusted life year (QALY) gained. We found that strategies incorporating the use of second-line drug regimens following first-line treatment failure were highly cost-effective compared to strategies using first-line drugs only. In our base case, standardized second-line treatment for confirmed MDR TB cases (STR2) had an incremental cost-effectiveness ratio of 720 dollars per QALY (8,700 dollars per averted death) compared to DOTS. Individualized second-line drug treatment for MDR TB following first-line failure (ITR1) provided more benefit at an incremental cost of 990 dollars per QALY (12,000 dollars per averted death) compared to STR2. A more aggressive version of the individualized treatment strategy (ITR2), in which both new and previously treated cases are tested for MDR TB, had an incremental cost-effectiveness ratio of 11,000 dollars per QALY (160,000 dollars per averted death) compared to ITR1. The STR2 and ITR1 strategies remained cost-effective under a wide range of alternative assumptions about treatment costs, effectiveness, MDR TB prevalence, and transmission. Treatment of MDR TB using second-line drugs is highly cost-effective in Peru. In other settings, the attractiveness of strategies using second-line drugs will depend on TB incidence, MDR burden, and the available budget, but simulation results suggest that individualized regimens would be cost-effective in a wide range of situations.

Artful and multifaceted applications of carbon dot in biomedicine.

PubMed

Jaleel, Jumana Abdul; Pramod, K

2018-01-10

Carbon dots (C-dots) are luminescent carbon nanomaterial having good biocompatibility and low toxicity. The characteristic fluorescence emission property of C-dots establishes their role in optical imaging. C-dots which are superior to fluorescent dyes and semiconductor quantum dots act as a safer in vivo imaging probe. Apart from their bioimaging application, other applications in biomedicine such as drug delivery, cancer therapy, and gene delivery were studied. In this review, we present multifaceted applications of C-dots along with their synthesis, surface passivation, doping, and toxicity profile. Copyright © 2017 Elsevier B.V. All rights reserved.

49 CFR 40.227 - May employers use the ATF for non-DOT tests, or non-DOT forms for DOT tests?

Code of Federal Regulations, 2014 CFR

2014-10-01

..., either by mistake, or as the only means to conduct a test under difficult circumstances (e.g., post... 49 Transportation 1 2014-10-01 2014-10-01 false May employers use the ATF for non-DOT tests, or non-DOT forms for DOT tests? 40.227 Section 40.227 Transportation Office of the Secretary of...

49 CFR 40.227 - May employers use the ATF for non-DOT tests, or non-DOT forms for DOT tests?

Code of Federal Regulations, 2011 CFR

2011-10-01

..., either by mistake, or as the only means to conduct a test under difficult circumstances (e.g., post... 49 Transportation 1 2011-10-01 2011-10-01 false May employers use the ATF for non-DOT tests, or non-DOT forms for DOT tests? 40.227 Section 40.227 Transportation Office of the Secretary of...

49 CFR 40.227 - May employers use the ATF for non-DOT tests, or non-DOT forms for DOT tests?

Code of Federal Regulations, 2012 CFR

2012-10-01

..., either by mistake, or as the only means to conduct a test under difficult circumstances (e.g., post... 49 Transportation 1 2012-10-01 2012-10-01 false May employers use the ATF for non-DOT tests, or non-DOT forms for DOT tests? 40.227 Section 40.227 Transportation Office of the Secretary of...

49 CFR 40.227 - May employers use the ATF for non-DOT tests, or non-DOT forms for DOT tests?

Code of Federal Regulations, 2010 CFR

2010-10-01

..., either by mistake, or as the only means to conduct a test under difficult circumstances (e.g., post... 49 Transportation 1 2010-10-01 2010-10-01 false May employers use the ATF for non-DOT tests, or non-DOT forms for DOT tests? 40.227 Section 40.227 Transportation Office of the Secretary of...

49 CFR 40.227 - May employers use the ATF for non-DOT tests, or non-DOT forms for DOT tests?

Code of Federal Regulations, 2013 CFR

2013-10-01

..., either by mistake, or as the only means to conduct a test under difficult circumstances (e.g., post... 49 Transportation 1 2013-10-01 2013-10-01 false May employers use the ATF for non-DOT tests, or non-DOT forms for DOT tests? 40.227 Section 40.227 Transportation Office of the Secretary of...

The Research and Applications of Quantum Dots as Nano-Carriers for Targeted Drug Delivery and Cancer Therapy

NASA Astrophysics Data System (ADS)

Zhao, Mei-Xia; Zhu, Bing-Jie

2016-04-01

Quantum dots (QDs), nano-carriers for drugs, can help realize the targeting of drugs, and improve the bioavailability of drugs in biological fields. And, a QD nano-carrier system for drugs has the potential to realize early detection, monitoring, and localized treatments of specific disease sites. In addition, QD nano-carrier systems for drugs can improve stability of drugs, lengthen circulation time in vivo, enhance targeted absorption, and improve the distribution and metabolism process of drugs in organization. So, the development of QD nano-carriers for drugs has become a hotspot in the fields of nano-drug research in recent years. In this paper, we review the advantages and applications of the QD nano-carriers for drugs in biological fields.

Drugs of Abuse in Aviation Fatalities. 1. Marijuana

DTIC Science & Technology

1985-08-01

h. DOT/FAA-:AM-85-8 V DRUGS OF ABUSE IN AVIATION FATALITIES: 1. MARIJUANA Delbert J. Lacefield Patricia A. Roberts Paula M. Grape Civil Aeromedical...Catalog No. DOT/FAA-AM-85-8 4. T.tle and Subtorle 5. Report Date Drugs of Abuse in Aviation Fatalities: 1. Marijuana AUGUST 1985 6. Performing Organization...47. 16. Abstract Isopropyl alcohol swabs taken from the oral cavities of pilots killed in general aviation accidents were analyzed for marijuana by

Feasibility and Cost-Effectiveness of Treating Multidrug-Resistant Tuberculosis: A Cohort Study in the Philippines

PubMed Central

Tupasi, Thelma E; Gupta, Rajesh; Quelapio, Ma Imelda D; Orillaza, Ruth B; Mira, Nona Rachel; Mangubat, Nellie V; Belen, Virgil; Arnisto, Nida; Macalintal, Lualhati; Arabit, Michael; Lagahid, Jaime Y; Espinal, Marcos; Floyd, Katherine

2006-01-01

Background Multidrug-resistant tuberculosis (MDR-TB) is an important global health problem, and a control strategy known as DOTS-Plus has existed since 1999. However, evidence regarding the feasibility, effectiveness, cost, and cost-effectiveness of DOTS-Plus is still limited. Methodology/Principal Findings We evaluated the feasibility, effectiveness, cost, and cost-effectiveness of a DOTS-Plus pilot project established at Makati Medical Center in Manila, the Philippines, in 1999. Patients with MDR-TB are treated with regimens, including first- and second-line drugs, tailored to their drug susceptibility pattern (i.e., individualised treatment). We considered the cohort enrolled between April 1999 and March 2002. During this three-year period, 118 patients were enrolled in the project; 117 were considered in the analysis. Seventy-one patients (61%) were cured, 12 (10%) failed treatment, 18 (15%) died, and 16 (14%) defaulted. The average cost per patient treated was US$3,355 from the perspective of the health system, of which US$1,557 was for drugs, and US$837 from the perspective of patients. The mean cost per disability-adjusted life year (DALY) gained by the DOTS-Plus project was US$242 (range US$85 to US$426). Conclusions Treatment of patients with MDR-TB using the DOTS-Plus strategy and individualised drug regimens can be feasible, comparatively effective, and cost-effective in low- and middle-income countries. PMID:16968123

Feasibility and cost-effectiveness of treating multidrug-resistant tuberculosis: a cohort study in the Philippines.

PubMed

Tupasi, Thelma E; Gupta, Rajesh; Quelapio, Ma Imelda D; Orillaza, Ruth B; Mira, Nona Rachel; Mangubat, Nellie V; Belen, Virgil; Arnisto, Nida; Macalintal, Lualhati; Arabit, Michael; Lagahid, Jaime Y; Espinal, Marcos; Floyd, Katherine

2006-09-01

Multidrug-resistant tuberculosis (MDR-TB) is an important global health problem, and a control strategy known as DOTS-Plus has existed since 1999. However, evidence regarding the feasibility, effectiveness, cost, and cost-effectiveness of DOTS-Plus is still limited. We evaluated the feasibility, effectiveness, cost, and cost-effectiveness of a DOTS-Plus pilot project established at Makati Medical Center in Manila, the Philippines, in 1999. Patients with MDR-TB are treated with regimens, including first- and second-line drugs, tailored to their drug susceptibility pattern (i.e., individualised treatment). We considered the cohort enrolled between April 1999 and March 2002. During this three-year period, 118 patients were enrolled in the project; 117 were considered in the analysis. Seventy-one patients (61%) were cured, 12 (10%) failed treatment, 18 (15%) died, and 16 (14%) defaulted. The average cost per patient treated was US3,355 dollars from the perspective of the health system, of which US1,557 dollars was for drugs, and US837 dollars from the perspective of patients. The mean cost per disability-adjusted life year (DALY) gained by the DOTS-Plus project was US242 dollars (range US85 dollars to US426 dollars). Treatment of patients with MDR-TB using the DOTS-Plus strategy and individualised drug regimens can be feasible, comparatively effective, and cost-effective in low- and middle-income countries.

Adverse reactions due to directly observed treatment strategy therapy in Chinese tuberculosis patients: a prospective study.

PubMed

Lv, Xiaozhen; Tang, Shaowen; Xia, Yinyin; Wang, Xiaomeng; Yuan, Yanli; Hu, Daiyu; Liu, Feiying; Wu, Shanshan; Zhang, Yuan; Yang, Zhirong; Tu, Dehua; Chen, Yixin; Deng, Peiyuan; Ma, Yu; Chen, Ru; Zhan, Siyan

2013-01-01

More than 1 million tuberculosis (TB) patients are receiving directly observed treatment strategy (DOTS) therapy in China every year. As to the profile of adverse drug reactions (ADRs) due to DOTS therapy, no consensus has been reached. There is no report regarding ADRs due to DOTS therapy with a large Chinese TB population. This study aimed to determine the incidence and prognosis of ADRs due to DOTS therapy, and to evaluate their impact on anti-TB treatment in China. A prospective population-based cohort study was performed during 2007-2008. Sputum smear positive pulmonary TB patients who received DOTS therapy were included and followed up for six to nine months in 52 counties of four regions in China. The suspected ADRs were recorded and reviewed by Chinese State Food and Drug Administration. A total of 4304 TB patients were included in this study. 649 patients (15.08%) showed at least one ADR and 766 cases in total were detected. The incidence (count) of ADR based on affected organ was: liver dysfunction 6.34% (273), gastrointestinal disorders 3.74% (161), arthralgia 2.51% (108), allergic reactions 2.35% (101), neurological system disorders 2.04% (88), renal impairment 0.07% (3) and others 0.05% (2). Most cases of ADRs (95%) had a good clinical outcome, while two with hepatotoxicity and one with renal impairment died. Compared with patients without ADRs, patients with ADRs were more likely to have positive smear test results at the end of the intensive phase (adjusted OR, 2.00; 95%CI, 1.44-2.78) and unsuccessful anti-TB outcomes (adjusted OR, 2.58; 95%CI, 1.43-4.68). The incidence of ADRs due to DOTS therapy was 15.08%. Those ADRs had a substantial impact on TB control in China. This highlighted the importance of developing strategies to ameliorate ADRs both to improve the quality of patient care and to control TB safely.

Internalization of targeted quantum dots by brain capillary endothelial cells in vivo.

PubMed

Paris-Robidas, Sarah; Brouard, Danny; Emond, Vincent; Parent, Martin; Calon, Frédéric

2016-04-01

Receptors located on brain capillary endothelial cells forming the blood-brain barrier are the target of most brain drug delivery approaches. Yet, direct subcellular evidence of vectorized transport of nanoformulations into the brain is lacking. To resolve this question, quantum dots were conjugated to monoclonal antibodies (Ri7) targeting the murine transferrin receptor. Specific transferrin receptor-mediated endocytosis of Ri7-quantum dots was first confirmed in N2A and bEnd5 cells. After intravenous injection in mice, Ri7-quantum dots exhibited a fourfold higher volume of distribution in brain tissues, compared to controls. Immunofluorescence analysis showed that Ri7-quantum dots were sequestered throughout the cerebral vasculature 30 min, 1 h, and 4 h post injection, with a decline of signal intensity after 24 h. Transmission electron microscopic studies confirmed that Ri7-quantum dots were massively internalized by brain capillary endothelial cells, averaging 37 ± 4 Ri7-quantum dots/cell 1 h after injection. Most quantum dots within brain capillary endothelial cells were observed in small vesicles (58%), with a smaller proportion detected in tubular structures or in multivesicular bodies. Parenchymal penetration of Ri7-quantum dots was extremely low and comparable to control IgG. Our results show that systemically administered Ri7-quantum dots complexes undergo extensive endocytosis by brain capillary endothelial cells and open the door for novel therapeutic approaches based on brain endothelial cell drug delivery. © The Author(s) 2015.

Multifunctional quantum dots and liposome complexes in drug delivery

PubMed Central

Wang, Qi; Chao, Yimin

2018-01-01

Incorporating both diagnostic and therapeutic functions into a single nanoscale system is an effective modern drug delivery strategy. Combining liposomes with semiconductor quantum dots (QDs) has great potential to achieve such dual functions, referred to in this review as a liposomal QD hybrid system (L-QD). Here we review the recent literature dealing with the design and application of L-QD for advances in bio-imaging and drug delivery. After a summary of L-QD synthesis processes and evaluation of their properties, we will focus on their multifunctional applications, ranging from in vitro cell imaging to theranostic drug delivery approaches. PMID:28866655

Multifunctional quantum dots and liposome complexes in drug delivery.

PubMed

Wang, Qi; Chao, Yi-Min

2017-09-03

Incorporating both diagnostic and therapeutic functions into a single nanoscale system is an effective modern drug delivery strategy. Combining liposomes with semiconductor quantum dots (QDs) has great potential to achieve such dual functions, referred to in this review as a liposomal QD hybrid system (L-QD). Here we review the recent literature dealing with the design and application of L-QD for advances in bio-imaging and drug delivery. After a summary of L-QD synthesis processes and evaluation of their properties, we will focus on their multifunctional applications, ranging from in vitro cell imaging to theranostic drug delivery approaches.

Department of Transportation

MedlinePlus

... The Briefing Room Connect With Us FEATURED RESOURCES Aviation Consumer Protection Motor Carriers - Get a DOT Number ... of Drug & Alcohol Policy & Compliance Register your Unmanned Aircraft or Drone DOT Careers Disadvantaged Business Enterprise (DBE) ...

Directly observed therapy of sofosbuvir/ribavirin +/- peginterferon with minimal monitoring for the treatment of chronic hepatitis C in people with a history of drug use in Chennai, India (C-DOT).

PubMed

Solomon, S S; Sulkowski, M S; Amrose, P; Srikrishnan, A K; McFall, A M; Ramasamy, B; Kumar, M S; Anand, S; Thomas, D L; Mehta, S H

2018-01-01

We assessed the feasibility of field-based directly observed therapy (DOT) with minimal monitoring to deliver HCV treatment to people with a history of drug use in Chennai, India. Fifty participants were randomized 1:1 to sofosbuvir+peginterferon alfa 2a+ribavirin (SOF+PR) for 12 weeks (Arm 1) vs sofosbuvir+ribavirin (SOF+R) for 24 weeks (Arm 2). SOF+R was delivered daily at participant chosen venues and weekly peginterferon injections at the study clinic. HCV RNA testing was performed to confirm active HCV infection and sustained virologic response 12 weeks after treatment completion (SVR12). No baseline genotyping or on-treatment viral loads were performed. Median age was 46 years. All were male and 20% had significant fibrosis/cirrhosis. All self-reported history of injection drug use, 18% recent noninjection drug use and 38% alcohol dependence. Six discontinued treatment (88% completed treatment in each arm). Of 22 who completed SOF+PR, all achieved SVR12 (22/25=88%); 15 of 22 who completed SOF+R achieved SVR12 (15/25=60%; P=.05). Among those completing SOF+R, SVR12 was significantly less common in participants reporting ongoing substance use (36% vs 100%) and missed doses. Active substance use and missed doses did not impact SVR with SOF+PR. Field-based DOT of HCV therapy without real-time HCV RNA monitoring was feasible; however, achieving 100% adherence was challenging. SOF+PR appeared superior to SOF+R in achieving SVR12, even when doses were missed with no discontinuations due to side effects. Further exploration of short duration treatment with peginterferon plus direct-acting antivirals is warranted. © 2017 John Wiley & Sons Ltd.

49 CFR 40.41 - Where does a urine collection for a DOT drug test take place?

Code of Federal Regulations, 2010 CFR

2010-10-01

... shipping of urine specimens to a laboratory, and a suitable clean surface for writing. (d) Your collection... section. (e) The first, and preferred, type of facility for urination that a collection site may include... event of a directly observed collection. (2) You must have a source of water for washing hands, that, if...

49 CFR 40.291 - What is the role of the SAP in the evaluation, referral, and treatment process of an employee who...

Code of Federal Regulations, 2010 CFR

2010-10-01

... employee to an appropriate education and/or treatment program; (3) Conducting a face-to-face follow-up evaluation to determine if the employee has actively participated in the education and/or treatment program..., referral, and treatment process of an employee who has violated DOT agency drug and alcohol testing...

49 CFR 40.287 - What information is an employer required to provide concerning SAP services to an employee who...

Code of Federal Regulations, 2010 CFR

2010-10-01

... provide concerning SAP services to an employee who has a DOT drug and alcohol regulation violation? 40.287... § 40.287 What information is an employer required to provide concerning SAP services to an employee who... (including an applicant or new employee) who violates a DOT drug and alcohol regulation a listing of SAPs...

Preparation and characterization of Fe3O4-Ag2O quantum dots decorated cellulose nanofibers as a carrier of anticancer drugs for skin cancer.

PubMed

Fakhri, Ali; Tahami, Shiva; Nejad, Pedram Afshar

2017-10-01

The Best performance drug delivery systems designed with Fe 3 O 4 -Ag 2 O quantum dots decorated cellulose nanofibers which that grafted with Etoposide and Methotrexate. Morphology properties were characterized by Scanning and Transmittance electron microscopy. The crystalline structure of prepared sample was evaluated using by X-ray diffraction. The vibrating sample magnetometer analysis was used for magnetic behavior of samples. The size distributions of Fe 3 O 4 -Ag 2 O QDs/Cellulose fibers nanocomposites indicate that the average diameter was 62.5nm. The Saturation magnetization (Ms) indicates the Fe 3 O 4 -Ag 2 O QDs/Cellulose fibers nanocomposites have ferromagnetic properties in nature. For make carrier, the Iron and Silver should be binds to cellulose nanofibers and to drug molecules and observe in UV-vis spectroscopy. The drug release kinetics was studied in vitro as spectrophotometrically. The release of Etoposide and Methotrexate were carried out with a constant speed, and the equilibrium reached at 24 and 30h with a total amount 78.94% and 63.84%, respectively. The results demonstrated that the obtained Fe 3 O 4 -Ag 2 O quantum dots/cellulose fibers nanocomposites could be applied for drug delivery systems. Cytotoxicity and antioxidant study confirmed the activity of the drug incorporated in nanocomposites. In addition, the cytotoxicity of drug was increased when loaded on nanocomposites, compared to pure Fe 3 O 4 -Ag 2 O quantum dots/cellulose fibers nanocomposites. Copyright © 2017 Elsevier B.V. All rights reserved.

49 CFR 32.400 - What are my responsibilities as a(n) DOT awarding official?

Code of Federal Regulations, 2010 CFR

2010-10-01

... obtain each recipient's agreement, as a condition of the award, to comply with the requirements in— (a... 49 Transportation 1 2010-10-01 2010-10-01 false What are my responsibilities as a(n) DOT awarding... REQUIREMENTS FOR DRUG-FREE WORKPLACE (FINANCIAL ASSISTANCE) Responsibilities of DOT Awarding Officials § 32.400...

49 CFR 32.400 - What are my responsibilities as a(n) DOT awarding official?

Code of Federal Regulations, 2014 CFR

2014-10-01

... obtain each recipient's agreement, as a condition of the award, to comply with the requirements in— (a... 49 Transportation 1 2014-10-01 2014-10-01 false What are my responsibilities as a(n) DOT awarding... REQUIREMENTS FOR DRUG-FREE WORKPLACE (FINANCIAL ASSISTANCE) Responsibilities of DOT Awarding Officials § 32.400...

49 CFR 32.400 - What are my responsibilities as a(n) DOT awarding official?

Code of Federal Regulations, 2011 CFR

2011-10-01

... obtain each recipient's agreement, as a condition of the award, to comply with the requirements in— (a... 49 Transportation 1 2011-10-01 2011-10-01 false What are my responsibilities as a(n) DOT awarding... REQUIREMENTS FOR DRUG-FREE WORKPLACE (FINANCIAL ASSISTANCE) Responsibilities of DOT Awarding Officials § 32.400...

Review – Quantum Dots and Their Application in Lighting, Displays, and Biology

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

Frecker, Talitha; Bailey, Danielle; Arzeta-Ferrer, Xochitl

2015-08-18

In this review, we focus on the advancement of white light emitting nanocrystals, their usage as the emissive layer in LEDs and display backlights, and examine the increased efficiency and longevity of quantum dots based colored LEDs. In addition, we also explore recent discoveries on quantum dots as biological labels, dynamic trackers, and applications in drug delivery.

Biocompatible Quantum Dots for Biological Applications

PubMed Central

Rosenthal, Sandra J.; Chang, Jerry C.; Kovtun, Oleg; McBride, James R.; Tomlinson, Ian D.

2011-01-01

Semiconductor quantum dots are quickly becoming a critical diagnostic tool for discerning cellular function at the molecular level. Their high brightness, long-lasting, sizetunable, and narrow luminescence set them apart from conventional fluorescence dyes. Quantum dots are being developed for a variety of biologically oriented applications, including fluorescent assays for drug discovery, disease detection, single protein tracking, and intracellular reporting. This review introduces the science behind quantum dots and describes how they are made biologically compatible. Several applications are also included, illustrating strategies toward target specificity, and are followed by a discussion on the limitations of quantum dot approaches. The article is concluded with a look at the future direction of quantum dots. PMID:21276935

Tuberculosis Costs in Spain and Related Factors.

PubMed

Gullón, José Antonio; García-García, José María; Villanueva, Manuel Ángel; Álvarez-Navascues, Fernando; Rodrigo, Teresa; Casals, Martí; Anibarro, Luis; García-Clemente, Marta María; Jiménez, María Ángeles; Bustamante, Ana; Penas, Antón; Caminero, José Antonio; Caylà, Joan

2016-12-01

To analyze the direct and indirect costs of diagnosis and management of tuberculosis (TB) and associated factors. Prospective study of patients diagnosed with TB between September 2014 and September 2015. We calculated direct (hospital stays, visits, diagnostic tests, and treatment) and indirect (sick leave and loss of productivity, contact tracing, and rehabilitation) costs. The following cost-related variables were compared: age, gender, country of origin, hospital stays, diagnostic testing, sensitivity testing, treatment, resistance, directed observed therapy (DOT), and days of sick leave. Proportions were compared using the chi-squared test and significant variables were included in a logistic regression analysis to calculate odds ratio (OR) and corresponding 95% confidence intervals. 319 patients were included with a mean age of 56.72±20.79 years. The average cost was €10,262.62±14,961.66, which increased significantly when associated with hospital admission, polymerase chain reaction, sputum smears and cultures, sensitvity testing, chest computed tomography, pleural biopsy, drug treatment longer than nine months, DOT and sick leave. In the multivariate analysis, hospitalization (OR=96.8; CI 29-472), sensitivity testing (OR=4.34; CI 1.71-12.1), chest CT (OR= 2.25; CI 1.08-4.77), DOT (OR=20.76; CI 4.11-148) and sick leave (OR=26,9; CI 8,51-122) showed an independent association with cost. Tuberculosis gives rise to significant health spending. In order to reduce these costs, more control of transmission, and fewer hospital admissions would be required. Copyright © 2016 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.

Validity of the Worth 4 Dot Test in Patients with Red-Green Color Vision Defect.

PubMed

Bak, Eunoo; Yang, Hee Kyung; Hwang, Jeong-Min

2017-05-01

The Worth four dot test uses red and green glasses for binocular dissociation, and although it has been believed that patients with red-green color vision defects cannot accurately perform the Worth four dot test, this has not been validated. Therefore, the purpose of this study was to demonstrate the validity of the Worth four dot test in patients with congenital red-green color vision defects who have normal or abnormal binocular vision. A retrospective review of medical records was performed on 30 consecutive congenital red-green color vision defect patients who underwent the Worth four dot test. The type of color vision anomaly was determined by the Hardy Rand and Rittler (HRR) pseudoisochromatic plate test, Ishihara color test, anomaloscope, and/or the 100 hue test. All patients underwent a complete ophthalmologic examination. Binocular sensory status was evaluated with the Worth four dot test and Randot stereotest. The results were interpreted according to the presence of strabismus or amblyopia. Among the 30 patients, 24 had normal visual acuity without strabismus nor amblyopia and 6 patients had strabismus and/or amblyopia. The 24 patients without strabismus nor amblyopia all showed binocular fusional responses by seeing four dots of the Worth four dot test. Meanwhile, the six patients with strabismus or amblyopia showed various results of fusion, suppression, and diplopia. Congenital red-green color vision defect patients of different types and variable degree of binocularity could successfully perform the Worth four dot test. They showed reliable results that were in accordance with their estimated binocular sensory status.

Signing below the dotted line: signature position as a marker of vulnerability for visuospatial processing difficulties

PubMed Central

Whitelock, Claire F; Agyepong, Heather NAO; Patterson, Karalyn; Ersche, Karen D

2015-01-01

Almost one-third of the participants in a neuropsychological study signed the consent form below the given line. The relationship between a signature position on or below the line and participants’ cognitive function was investigated. Fifty drug-dependent individuals, 50 of their siblings, and 50 unrelated control participants completed a battery of neuropsychological tests using the Cambridge Neuropsychological Test Automated Battery (CANTAB). Individuals signing below, rather than on, the line performed more poorly on tests of visuospatial memory, but no differently on other cognitive tests. Signature positioning may be a soft sign for impairment of the mechanisms involved in visuospatial memory. PMID:24313358

Drug-resistant tuberculosis--current dilemmas, unanswered questions, challenges, and priority needs.

PubMed

Zumla, Alimuddin; Abubakar, Ibrahim; Raviglione, Mario; Hoelscher, Michael; Ditiu, Lucica; McHugh, Timothy D; Squire, S Bertel; Cox, Helen; Ford, Nathan; McNerney, Ruth; Marais, Ben; Grobusch, Martin; Lawn, Stephen D; Migliori, Giovanni-Battista; Mwaba, Peter; O'Grady, Justin; Pletschette, Michel; Ramsay, Andrew; Chakaya, Jeremiah; Schito, Marco; Swaminathan, Soumya; Memish, Ziad; Maeurer, Markus; Atun, Rifat

2012-05-15

Tuberculosis was declared a global emergency by the World Health Organization (WHO) in 1993. Following the declaration and the promotion in 1995 of directly observed treatment short course (DOTS), a cost-effective strategy to contain the tuberculosis epidemic, nearly 7 million lives have been saved compared with the pre-DOTS era, high cure rates have been achieved in most countries worldwide, and the global incidence of tuberculosis has been in a slow decline since the early 2000s. However, the emergence and spread of multidrug-resistant (MDR) tuberculosis, extensively drug-resistant (XDR) tuberculosis, and more recently, totally drug-resistant tuberculosis pose a threat to global tuberculosis control. Multidrug-resistant tuberculosis is a man-made problem. Laboratory facilities for drug susceptibility testing are inadequate in most tuberculosis-endemic countries, especially in Africa; thus diagnosis is missed, routine surveillance is not implemented, and the actual numbers of global drug-resistant tuberculosis cases have yet to be estimated. This exposes an ominous situation and reveals an urgent need for commitment by national programs to health system improvement because the response to MDR tuberculosis requires strong health services in general. Multidrug-resistant tuberculosis and XDR tuberculosis greatly complicate patient management within resource-poor national tuberculosis programs, reducing treatment efficacy and increasing the cost of treatment to the extent that it could bankrupt healthcare financing in tuberculosis-endemic areas. Why, despite nearly 20 years of WHO-promoted activity and >12 years of MDR tuberculosis-specific activity, has the country response to the drug-resistant tuberculosis epidemic been so ineffectual? The current dilemmas, unanswered questions, operational issues, challenges, and priority needs for global drug resistance screening and surveillance, improved treatment regimens, and management of outcomes and prevention of DR tuberculosis are discussed.

A New Method to Directly Observe Tuberculosis Treatment: Skype Observed Therapy, a Patient-Centered Approach.

PubMed

Buchman, Tavora; Cabello, Celina

Tuberculosis (TB) treatment completion is in part determined by patient's adherence to long-term drug regimens. To best ensure compliance, directly observed therapy (DOT) is considered the standard of practice. Nassau County Department of Health TB Control is responsible for providing DOT to patients with TB. Tuberculosis Control sought to use and evaluate Skype Observed Therapy (SOT) as an alternative to DOT for eligible patients. The evaluation included analysis of patient's acceptance and adherence to drug regimen using SOT. Tuberculosis Control assessed staff efficiency and cost savings for this program. Percentages of SOT of patients and successful SOT visits, mileage, and travel time savings. Twenty percent of the caseload used SOT and 100% of patients who were eligible opted in. Average SOT success was 79%. Total mileage savings and time saved were $9,929.07 and 614 hours. Because SOT saves cost and time and is a suitable alternative to DOT for patients, it should be considered as part of new policies and practices in TB control programs.

Gold–silica quantum rattles for multimodal imaging and therapy

PubMed Central

Hembury, Mathew; Chiappini, Ciro; Bertazzo, Sergio; Kalber, Tammy L.; Drisko, Glenna L.; Ogunlade, Olumide; Walker-Samuel, Simon; Krishna, Katla Sai; Jumeaux, Coline; Beard, Paul; Kumar, Challa S. S. R.; Porter, Alexandra E.; Lythgoe, Mark F.; Boissière, Cédric; Sanchez, Clément; Stevens, Molly M.

2015-01-01

Gold quantum dots exhibit distinctive optical and magnetic behaviors compared with larger gold nanoparticles. However, their unfavorable interaction with living systems and lack of stability in aqueous solvents has so far prevented their adoption in biology and medicine. Here, a simple synthetic pathway integrates gold quantum dots within a mesoporous silica shell, alongside larger gold nanoparticles within the shell’s central cavity. This “quantum rattle” structure is stable in aqueous solutions, does not elicit cell toxicity, preserves the attractive near-infrared photonics and paramagnetism of gold quantum dots, and enhances the drug-carrier performance of the silica shell. In vivo, the quantum rattles reduced tumor burden in a single course of photothermal therapy while coupling three complementary imaging modalities: near-infrared fluorescence, photoacoustic, and magnetic resonance imaging. The incorporation of gold within the quantum rattles significantly enhanced the drug-carrier performance of the silica shell. This innovative material design based on the mutually beneficial interaction of gold and silica introduces the use of gold quantum dots for imaging and therapeutic applications. PMID:25653336

Biocompatible yogurt carbon dots: evaluation of utilization for medical applications

NASA Astrophysics Data System (ADS)

Dinç, Saliha; Kara, Meryem; Demirel Kars, Meltem; Aykül, Fatmanur; Çiçekci, Hacer; Akkuş, Mehmet

2017-09-01

In this study, carbon dots (CDs) were produced from yogurt, a fermented milk product, via microwave-assisted process (800 W) in 30 min without using any additional chemical agents. Yogurt CDs had outstanding nitrogen and oxygen ratios. These dots were monodisperse and about 2 nm sized. The toxicological assessments of yogurt carbon dots in human cancer cells and normal epithelial cells and their fluorescence imaging in living cell system were carried out. Yogurt carbon dots had intense fluorescent signal under confocal microscopy and good fluorescence stability in living cell system. The resulting yogurt carbon dots exhibited high biocompatibility up to 7.1 mg/mL CD concentration which may find utilization in medical applications such as cellular tracking, imaging and drug delivery. Yogurt carbon dots have potential to be good diagnostic agents to visualize cancer cells which may be developed as a therapeutic carrier.

The future of quantum dots in drug discovery.

PubMed

Lin, Guimiao; Yin, Feng; Yong, Ken-Tye

2014-09-01

The rapid development of drug discovery today is inseparable from the interaction of advanced particle technologies and new drug synthesis protocols. Quantum dots (QDs) are regarded as a unique class of fluorescent labels, with unique optical properties such as high brightness and long-term colloidal and optical stability; these are suitable for optical imaging, drug delivery and optical tracking, fluorescence immunoassay and other medicinal applications. More importantly, QD possesses a rich surface chemistry property that is useful for incorporating various drug molecules, targeting ligands, and additional contrast agents (e.g., MRI, PET, etc.) onto the nanoparticle surface for achieving targeted and traceable drug delivery therapy at both cellular and systemic levels. In recent times, the advancement of QD technology has promoted the use of functionalized nanocrystals for in vivo applications. Such research is paving the way for drug discovery using various bioconjugated QD formulations. In this editorial, the authors highlight the current research progress and future applications of QDs in drug discovery.

Directly observed treatment, short-course strategy and multidrug-resistant tuberculosis: are any modifications required?

PubMed Central

Bastian, I.; Rigouts, L.; Van Deun, A.; Portaels, F.

2000-01-01

Multidrug-resistant tuberculosis (MDRTB) should be defined as tuberculosis with resistance to at least isoniazid and rifampicin because these drugs are the cornerstone of short-course chemotherapy, and combined isoniazid and rifampicin resistance requires prolonged treatment with second-line agents. Short-course chemotherapy is a key ingredient in the tuberculosis control strategy known as directly observed treatment, short-course (DOTS). For populations in which multidrug-resistant tuberculosis is endemic, the outcome of the standard short-course chemotherapy regimen remains uncertain. Unacceptable failure rates have been reported and resistance to additional agents may be induced. As a consequence there have been calls for well-functioning DOTS programmes to provide additional services in areas with high rates of multidrug-resistant tuberculosis. These "DOTS-plus for MDRTB programmes" may need to modify all five elements of the DOTS strategy: the treatment may need to be individualized rather than standardized; laboratory services may need to provide facilities for on-site culture and antibiotic susceptibility testing; reliable supplies of a wide range of expensive second-line agents would have to be supplied; operational studies would be required to determine the indications for and format of the expanded programmes; financial and technical support from international organizations and Western governments would be needed in addition to that obtained from local governments. PMID:10743297

Cross-validation of the Dot Counting Test in a large sample of credible and non-credible patients referred for neuropsychological testing.

PubMed

McCaul, Courtney; Boone, Kyle B; Ermshar, Annette; Cottingham, Maria; Victor, Tara L; Ziegler, Elizabeth; Zeller, Michelle A; Wright, Matthew

2018-01-18

To cross-validate the Dot Counting Test in a large neuropsychological sample. Dot Counting Test scores were compared in credible (n = 142) and non-credible (n = 335) neuropsychology referrals. Non-credible patients scored significantly higher than credible patients on all Dot Counting Test scores. While the original E-score cut-off of ≥17 achieved excellent specificity (96.5%), it was associated with mediocre sensitivity (52.8%). However, the cut-off could be substantially lowered to ≥13.80, while still maintaining adequate specificity (≥90%), and raising sensitivity to 70.0%. Examination of non-credible subgroups revealed that Dot Counting Test sensitivity in feigned mild traumatic brain injury (mTBI) was 55.8%, whereas sensitivity was 90.6% in patients with non-credible cognitive dysfunction in the context of claimed psychosis, and 81.0% in patients with non-credible cognitive performance in depression or severe TBI. Thus, the Dot Counting Test may have a particular role in detection of non-credible cognitive symptoms in claimed psychiatric disorders. Alternative to use of the E-score, failure on ≥1 cut-offs applied to individual Dot Counting Test scores (≥6.0″ for mean grouped dot counting time, ≥10.0″ for mean ungrouped dot counting time, and ≥4 errors), occurred in 11.3% of the credible sample, while nearly two-thirds (63.6%) of the non-credible sample failed one of more of these cut-offs. An E-score cut-off of 13.80, or failure on ≥1 individual score cut-offs, resulted in few false positive identifications in credible patients, and achieved high sensitivity (64.0-70.0%), and therefore appear appropriate for use in identifying neurocognitive performance invalidity.

Comparison between DOT EIA IgM and Widal Test as early diagnosis of typhoid fever.

PubMed

Begum, Z; Hossain, M A; Musa, A K; Shamsuzzaman, A K; Mahmud, M C; Ahsan, M M; Sumona, A A; Ahmed, S; Jahan, N A; Alam, M; Begum, A

2009-01-01

A recently developed DOT enzyme immunoassay known as "Typhidot" for detecting IgM antibody against 50 KDa OMP antigen of Salmonella typhi, was evaluated on 100 clinically suspected typhoid fever cases and 40 age-sex matched controls, in the Department of Microbiology, Mymensingh Medical College during, the period from June 2006 to July 2007. Blood culture, Widal test, and DOT EIA for IgM test were performed in all patients. Among 100 clinically suspected typhoid fever cases, 35 were subsequently confirmed on the basis of positive blood culture for S. typhi and/or significant rising titre of Widal test. The DOT EIA IgM test could produce results within 1 hour. The result of the DOT EIA IgM test showed a good diagnostic value for typhoid fever. The sensitivity, specificity, positive and negative predictive value of the test was found as 91.42%, 90.00%, 88.88% and 92.30% respectively. On the other hand corresponding values for Widal test were of 42.85%, 85.00%, 71.42% and 62.96% respectively. Thus, The DOT EIA IgM seems to be a practical alternative to Widal test for early diagnosis of typhoid fever.

DOT1L and H3K79 Methylation in Transcription and Genomic Stability.

PubMed

Wood, Katherine; Tellier, Michael; Murphy, Shona

2018-02-27

The organization of eukaryotic genomes into chromatin provides challenges for the cell to accomplish basic cellular functions, such as transcription, DNA replication and repair of DNA damage. Accordingly, a range of proteins modify and/or read chromatin states to regulate access to chromosomal DNA. Yeast Dot1 and the mammalian homologue DOT1L are methyltransferases that can add up to three methyl groups to histone H3 lysine 79 (H3K79). H3K79 methylation is implicated in several processes, including transcription elongation by RNA polymerase II, the DNA damage response and cell cycle checkpoint activation. DOT1L is also an important drug target for treatment of mixed lineage leukemia (MLL)-rearranged leukemia where aberrant transcriptional activation is promoted by DOT1L mislocalisation. This review summarizes what is currently known about the role of Dot1/DOT1L and H3K79 methylation in transcription and genomic stability.

Gold–silica quantum rattles for multimodal imaging and therapy

DOE PAGES

Hembury, Mathew; Chiappini, Ciro; Bertazzo, Sergio; ...

2015-02-04

Gold quantum dots exhibit distinctive optical and magnetic behaviors compared with larger gold nanoparticles. However, their unfavorable interaction with living systems and lack of stability in aqueous solvents has so far prevented their adoption in biology and medicine. In this paper, a simple synthetic pathway integrates gold quantum dots within a mesoporous silica shell, alongside larger gold nanoparticles within the shell’s central cavity. This “quantum rattle” structure is stable in aqueous solutions, does not elicit cell toxicity, preserves the attractive near-infrared photonics and paramagnetism of gold quantum dots, and enhances the drug-carrier performance of the silica shell. In vivo, themore » quantum rattles reduced tumor burden in a single course of photothermal therapy while coupling three complementary imaging modalities: near-infrared fluorescence, photoacoustic, and magnetic resonance imaging. The incorporation of gold within the quantum rattles significantly enhanced the drug-carrier performance of the silica shell. Finally, this innovative material design based on the mutually beneficial interaction of gold and silica introduces the use of gold quantum dots for imaging and therapeutic applications.« less

Quantum Dots in the Therapy: Current Trends and Perspectives.

PubMed

Pohanka, Miroslav

2017-01-01

Quantum dots are an emerging nanomaterial with broad use in technical disciplines; however, their application in the field of biomedicine becomes also relevant and significant possibilities have appeared since the discovery in 1980s. The current review is focused on the therapeutic applications of quantum dots which become an emerging use of the particles. They are introduced as potent carriers of drugs and as a material well suited for the diagnosis of disparate pathologies like visualization of cancer cells or pathogenic microorganisms. Quantum dots toxicity and modifications for the toxicity reduction are discussed here as well. Survey of actual papers and patents in the field of quantum dots use in the biomedicine is provided. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Quantum Dots Applied to Methodology on Detection of Pesticide and Veterinary Drug Residues.

PubMed

Zhou, Jia-Wei; Zou, Xue-Mei; Song, Shang-Hong; Chen, Guan-Hua

2018-02-14

The pesticide and veterinary drug residues brought by large-scale agricultural production have become one of the issues in the fields of food safety and environmental ecological security. It is necessary to develop the rapid, sensitive, qualitative and quantitative methodology for the detection of pesticide and veterinary drug residues. As one of the achievements of nanoscience, quantum dots (QDs) have been widely used in the detection of pesticide and veterinary drug residues. In these methodology studies, the used QD-signal styles include fluorescence, chemiluminescence, electrochemical luminescence, photoelectrochemistry, etc. QDs can also be assembled into sensors with different materials, such as QD-enzyme, QD-antibody, QD-aptamer, and QD-molecularly imprinted polymer sensors, etc. Plenty of study achievements in the field of detection of pesticide and veterinary drug residues have been obtained from the different combinations among these signals and sensors. They are summarized in this paper to provide a reference for the QD application in the detection of pesticide and veterinary drug residues.

Red Dot Basal Cell Carcinoma: An Unusual Variant of a Common Malignancy.

PubMed

Loh, Tiffany Y; Cohen, Philip R

2016-05-01

Red dot basal cell carcinoma is a distinct but rare subtype of basal cell carcinoma (BCC). It presents as a red macule or papule; therefore, in most cases, it may easily be mistaken for a benign vascular lesion, such as a telangiectasia or angioma.
A red dot BCC in an older woman is described. Clinical and histological differences between red dot BCCs and telangiectasias are described.
A 72-year-old woman initially presented with a painless red macule on her nose. Biopsy of the lesion established the diagnosis of a red dot BCC. Pubmed was searched for the following terms: angioma, basal cell carcinoma, dermoscope, diascopy, red dot, non-melanoma skin cancer, telangiectasia, and vascular. The papers were reviewed for cases of red dot basal cell carcinoma. Clinical and histological characteristics of red dot basal cell carcinoma and telangiectasias were compared.
Red dot BCC is an extremely rare variant of BCC that may be confused with benign vascular lesions. Although BCCs rarely metastasize and are associated with low mortality, they have the potential to become locally invasive and destructive if left untreated. Thus, a high index of suspicion for red dot BCC is necessary.

J Drugs Dermatol. 2016;15(5):645-647.

Tuberculosis-Related Deaths within a Well-Functioning DOTS Control Program

PubMed Central

García-García, Maria de Lourdes; Ponce-de-León, Alfredo; García-Sancho, Maria Cecilia; Ferreyra-Reyes, Leticia; Palacios-Martínez, Manuel; Fuentes, Javier; Kato-Maeda, Midori; Bobadilla, Miriam; Small, Peter; Sifuentes-Osornio, José

2002-01-01

To describe the molecular epidemiology of tuberculosis (TB)-related deaths in a well-managed program in a low-HIV area, we analyzed data from a cohort of 454 pulmonary TB patients recruited between March 1995 and October 2000 in southern Mexico. Patients who were sputum acid-fast bacillus smear positive underwent clinical and mycobacteriologic evaluation (isolation, identification, drug-susceptibility testing, and IS6110-based genotyping and spoligotyping) and received treatment from the local directly observed treatment strategy (DOTS) program. After an average of 2.3 years of follow-up, death was higher for clustered cases (28.6 vs. 7%, p=0.01). Cox analysis revealed that TB-related mortality hazard ratios included treatment default (8.9), multidrug resistance (5.7), recently transmitted TB (4.1), weight loss (3.9), and having less than 6 years of formal education (2). In this community, TB is associated with high mortality rates. PMID:12453365

Drug Usage in Pilots Involved in Aviation Accidents Compared With Drug Usage in the General Population: From 1990 to 2005

DTIC Science & Technology

2008-04-01

Unclassified 11 Form DOT F 1700.7 (8-72) Reproduction of completed page authorized 1 DRUG USAGE IN PILOTS INVOLVED IN AVIATION ACCIDENTS COMPARED WITH DRUG...0.01% during the examined time period (5192 accidents). Benzodiazepines Psychotherapeutic agents, anxiolytics, sedatives, and hypnotics occurred in

An aftereffect of adaptation to mean size

PubMed Central

Corbett, Jennifer E.; Wurnitsch, Nicole; Schwartz, Alex; Whitney, David

2013-01-01

The visual system rapidly represents the mean size of sets of objects. Here, we investigated whether mean size is explicitly encoded by the visual system, along a single dimension like texture, numerosity, and other visual dimensions susceptible to adaptation. Observers adapted to two sets of dots with different mean sizes, presented simultaneously in opposite visual fields. After adaptation, two test patches replaced the adapting dot sets, and participants judged which test appeared to have the larger average dot diameter. They generally perceived the test that replaced the smaller mean size adapting set as being larger than the test that replaced the larger adapting set. This differential aftereffect held for single test dots (Experiment 2) and high-pass filtered displays (Experiment 3), and changed systematically as a function of the variance of the adapting dot sets (Experiment 4), providing additional support that mean size is adaptable, and therefore explicitly encoded dimension of visual scenes. PMID:24348083

Efficient analytical implementation of the DOT Riemann solver for the de Saint Venant-Exner morphodynamic model

NASA Astrophysics Data System (ADS)

Carraro, F.; Valiani, A.; Caleffi, V.

2018-03-01

Within the framework of the de Saint Venant equations coupled with the Exner equation for morphodynamic evolution, this work presents a new efficient implementation of the Dumbser-Osher-Toro (DOT) scheme for non-conservative problems. The DOT path-conservative scheme is a robust upwind method based on a complete Riemann solver, but it has the drawback of requiring expensive numerical computations. Indeed, to compute the non-linear time evolution in each time step, the DOT scheme requires numerical computation of the flux matrix eigenstructure (the totality of eigenvalues and eigenvectors) several times at each cell edge. In this work, an analytical and compact formulation of the eigenstructure for the de Saint Venant-Exner (dSVE) model is introduced and tested in terms of numerical efficiency and stability. Using the original DOT and PRICE-C (a very efficient FORCE-type method) as reference methods, we present a convergence analysis (error against CPU time) to study the performance of the DOT method with our new analytical implementation of eigenstructure calculations (A-DOT). In particular, the numerical performance of the three methods is tested in three test cases: a movable bed Riemann problem with analytical solution; a problem with smooth analytical solution; a test in which the water flow is characterised by subcritical and supercritical regions. For a given target error, the A-DOT method is always the most efficient choice. Finally, two experimental data sets and different transport formulae are considered to test the A-DOT model in more practical case studies.

Enhancing Cell Nucleus Accumulation and DNA Cleavage Activity of Anti-Cancer Drug via Graphene Quantum Dots

NASA Astrophysics Data System (ADS)

Wang, Chong; Wu, Congyu; Zhou, Xuejiao; Han, Ting; Xin, Xiaozhen; Wu, Jiaying; Zhang, Jingyan; Guo, Shouwu

2013-10-01

Graphene quantum dots (GQDs) maintain the intrinsic layered structural motif of graphene but with smaller lateral size and abundant periphery carboxylic groups, and are more compatible with biological system, thus are promising nanomaterials for therapeutic applications. Here we show that GQDs have a superb ability in drug delivery and anti-cancer activity boost without any pre-modification due to their unique structural properties. They could efficiently deliver doxorubicin (DOX) to the nucleus through DOX/GQD conjugates, because the conjugates assume different cellular and nuclear internalization pathways comparing to free DOX. Also, the conjugates could enhance DNA cleavage activity of DOX markedly. This enhancement combining with efficient nuclear delivery improved cytotoxicity of DOX dramatically. Furthermore, the DOX/GQD conjugates could also increase the nuclear uptake and cytotoxicity of DOX to drug-resistant cancer cells indicating that the conjugates may be capable to increase chemotherapy efficacy of anti-cancer drugs that are suboptimal due to the drug resistance.

Design and Simulation Test of an Open D-Dot Voltage Sensor

PubMed Central

Bai, Yunjie; Wang, Jingang; Wei, Gang; Yang, Yongming

2015-01-01

Nowadays, sensor development focuses on miniaturization and non-contact measurement. According to the D-dot principle, a D-dot voltage sensor with a new structure was designed based on the differential D-dot sensor with a symmetrical structure, called an asymmetric open D-dot voltage sensor. It is easier to install. The electric field distribution of the sensor was analyzed through Ansoft Maxwell and an open D-dot voltage sensor was designed. This open D-voltage sensor is characteristic of accessible insulating strength and small electric field distortion. The steady and transient performance test under 10 kV-voltage reported satisfying performances of the designed open D-dot voltage sensor. It conforms to requirements for a smart grid measuring sensor in intelligence, miniaturization and facilitation. PMID:26393590

Side impact test and analysis of a DOT-112 tank car.

DOT National Transportation Integrated Search

2016-12-01

As part of a program to improve transportation safety for tank cars, Transportation Technology Center, Inc. (TTCI) has conducted a side impact test on a DOT-112 tank car to evaluate the performance of the DOT-112 under dynamic impact conditions and t...

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

Simulation Test System of Non-Contact D-dot Voltage Transformer

NASA Astrophysics Data System (ADS)

Yang, Jie; Wang, Jingang; Luo, Ruixi; Gao, Can; Songnong, Li; Kongjun, Zhou

2016-04-01

The development trend of future voltage transformer in smart grid is non-contact measurement, miniaturization and intellectualization. This paper proposes one simulation test system of non-contact D-dot transformer for voltage measurement. This simulation test system consists of D-dot transformer, signal processing circuit and ground PC port. D-dot transformer realizes the indirect voltage measurement by measuring the change rate of electric displacement vector, a non-contact means (He et al. 2004, Principles and experiments of voltage transformer based on self-integrating D-dot probe. Proc CSEE 2014;15:2445-51). Specific to the characteristics of D-dot transformer signals, signal processing circuits with strong resistance to interference and distortion-free amplified sensor output signal are designed. WIFI wireless network is used to transmit the voltage detection to LabVIEW-based ground collection port and LabVIEW technology is adopted for signal reception, data processing and analysis and other functions. Finally, a test platform is established to simulate the performance of the whole test system of single-phase voltage transformer. Test results indicate that this voltage transformer has sound real-time performance, high accuracy and fast response speed and the simulation test system is stable and reliable and can be a new prototype of voltage transformers.

Performance of photocatalyst based carbon nanodots from waste frying oil in water purification

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

Aji, Mahardika Prasetya, E-mail: mahardika190@gmail.com; Wiguna, Pradita Ajeng; Susanto,

Carbon Nanodots (C-Dots) from waste frying oil could be used as a photocatalyst in water purification with solar light irradiation. Performance of C-Dots as a photocatalyst was tested in the process of water purification with a given synthetic sewage methylene blue. The tested was also conducted by comparing the performance C-Dots made from frying oil, waste fryng oil as a photocatalyst and solution of methylene blue without photocatalyst C-Dots. Performance of C-Dots from waste frying oil were estimated by the results of absorbance spectrum. The results of measurement absorbance spectrum from the process of water purification with photocatalyst C-Dots showedmore » that the highest intensity at a wavelength 664 nm of methylene blue decreased. The test results showed that the performance of photocatalyst C-Dots from waste frying oil was better in water purification. This estimated that number of particles C-dots is more in waste frying oil because have experieced repeated the heating process so that the higher particles concentration make the photocatalyst process more effective. The observation of the performance C-Dots from waste frying oil as a photocatalyst in the water purification processes become important invention for solving the problems of waste and water purification.« less

Monitoring early tumor response to drug therapy with diffuse optical tomography

NASA Astrophysics Data System (ADS)

Flexman, Molly L.; Vlachos, Fotios; Kim, Hyun Keol; Sirsi, Shashank R.; Huang, Jianzhong; Hernandez, Sonia L.; Johung, Tessa B.; Gander, Jeffrey W.; Reichstein, Ari R.; Lampl, Brooke S.; Wang, Antai; Borden, Mark A.; Yamashiro, Darrell J.; Kandel, Jessica J.; Hielscher, Andreas H.

2012-01-01

Although anti-angiogenic agents have shown promise as cancer therapeutics, their efficacy varies between tumor types and individual patients. Providing patient-specific metrics through rapid noninvasive imaging can help tailor drug treatment by optimizing dosages, timing of drug cycles, and duration of therapy--thereby reducing toxicity and cost and improving patient outcome. Diffuse optical tomography (DOT) is a noninvasive three-dimensional imaging modality that has been shown to capture physiologic changes in tumors through visualization of oxygenated, deoxygenated, and total hemoglobin concentrations, using non-ionizing radiation with near-infrared light. We employed a small animal model to ascertain if tumor response to bevacizumab (BV), an anti-angiogenic agent that targets vascular endothelial growth factor (VEGF), could be detected at early time points using DOT. We detected a significant decrease in total hemoglobin levels as soon as one day after BV treatment in responder xenograft tumors (SK-NEP-1), but not in SK-NEP-1 control tumors or in non-responder control or BV-treated NGP tumors. These results are confirmed by magnetic resonance imaging T2 relaxometry and lectin perfusion studies. Noninvasive DOT imaging may allow for earlier and more effective control of anti-angiogenic therapy.

Glutathione responsive micelles incorporated with semiconducting polymer dots and doxorubicin for cancer photothermal-chemotherapy

NASA Astrophysics Data System (ADS)

Cai, Zhixiong; Zhang, Da; Lin, Xinyi; Chen, Yunzhu; Wu, Ming; Wei, Zuwu; Zhang, Zhenxi; Liu, Xiaolong; Yao, Cuiping

2017-10-01

Nanoplatform integrated with photothermal therapy (PTT) and chemotherapy has been recognized a promising agent for enhancing cancer therapeutic outcomes, but still suffer from less controllability for optimizing their synergistic effects. We fabricated glutathione (GSH) responsive micelles incorporated with semiconducting polymer dots and doxorubicin (referred as SPDOX NPs) for combining PTT with chemotherapy to enhance cancer therapeutic efficiency. These micelles, with excellent water dispersibility, comprises of three distinct functional components: (1) the monomethoxy-poly(ethylene glycol)-S-S-hexadecyl (mPEG-S-S-C16), which forms the micelles, can render hydrophobic substances water-soluble and improve the colloidal stability; (2) disulfide linkages can be cleaved in a reductive environment for tumor specific drug release due to the high GSH concentrations of tumor micro-environment; (3) PCPDTBT dots and anti-cancer drug DOX that are loaded inside the hydrophobic core of the micelle can be applied to simultaneously perform PTT and chemotherapy to achieve significantly enhanced tumor killing efficiency both in vitro and in vivo. In summary, our studies demonstrated that our SPDOX NPs with simultaneous photothermal-chemotherapy functions could be a promising platform for a tumor specific responsive drug delivery system.

The cost-effectiveness of directly observed highly-active antiretroviral therapy in the third trimester in HIV-infected pregnant women.

PubMed

McCabe, Caitlin J; Goldie, Sue J; Fisman, David N

2010-04-13

In HIV-infected pregnant women, viral suppression prevents mother-to-child HIV transmission. Directly observed highly-active antiretroviral therapy (HAART) enhances virological suppression, and could prevent transmission. Our objective was to project the effectiveness and cost-effectiveness of directly observed administration of antiretroviral drugs in pregnancy. A mathematical model was created to simulate cohorts of one million asymptomatic HIV-infected pregnant women on HAART, with women randomly assigned self-administered or directly observed antiretroviral therapy (DOT), or no HAART, in a series of Monte Carlo simulations. Our primary outcome was the quality-adjusted life expectancy in years (QALY) of infants born to HIV-infected women, with the rates of Caesarean section and HIV-transmission after DOT use as intermediate outcomes. Both self-administered HAART and DOT were associated with decreased costs and increased life-expectancy relative to no HAART. The use of DOT was associated with a relative risk of HIV transmission of 0.39 relative to conventional HAART; was highly cost-effective in the cohort as a whole (cost-utility ratio $14,233 per QALY); and was cost-saving in women whose viral loads on self-administered HAART would have exceeded 1000 copies/ml. Results were stable in wide-ranging sensitivity analyses, with directly observed therapy cost-saving or highly cost-effective in almost all cases. Based on the best available data, programs that optimize adherence to HAART through direct observation in pregnancy have the potential to diminish mother-to-child HIV transmission in a highly cost-effective manner. Targeted use of DOT in pregnant women with high viral loads, who could otherwise receive self-administered HAART would be a cost-saving intervention. These projections should be tested with randomized clinical trials.

An Investigation of the Height of Embossed Braille Dots for Labels on Pharmaceutical Products

ERIC Educational Resources Information Center

Douglas, Graeme; Weston, Annette; Whittaker, Jennifer; Wilkins, Sarah Morley; Robinson, Duncan

2009-01-01

European legislation requires new pharmaceutical packaging to include both the name and strength of the drug in braille on boxes and bottles. Much of the braille on medical packaging is currently produced by an embossing process on boxes. The height of the dots that can be achieved through these methods is less than 0.3 mm. The physical dimensions…

Nanoscale science and engineering forum (706c) design of solid lipid particles with iron oxide quantum dots for the delivery of therapeutic agents

USDA-ARS?s Scientific Manuscript database

Solid lipid particles provide a method to encapsulate and control the release of drugs in vivo but lack the imaging capability provided by CdS quantum dots. This shortcoming was addressed by combining these two technologies into a model system that uses iron oxide as a non-toxic imaging component in...

Directory of Academic Institutions and Organizations Offering Drug, Alcohol, and Employee Assistance Program Educational Resources.

ERIC Educational Resources Information Center

National Inst. on Drug Abuse (DHHS/PHS), Rockville, MD.

This directory lists academic institutions, State offices of alcohol and drug abuse, and national organizations which offer drug, alcohol, and employee assistance program (EAP) educational resources. A matrix format is used. Entries include name, address, telephone number, and contact person. A dot appears directly under column headings which are…

In vivo skin penetration of macromolecules in irritant contact dermatitis.

PubMed

Abdel-Mottaleb, Mona M A; Lamprecht, Alf

2016-12-30

Recently, a selective preferential accumulation of polymeric nanoparticles (in the size range around 100nm) has been observed in the follicular system of dermatitis skin. The present investigation aimed at clearly investigating the effect of irritant contact dermatitis on the barrier permeability for colloidal systems below this size range, namely quantum dots and hydrophilic macromolecules. Irritant dermatitis was induced in mice and the penetrability of quantum dots (5nm) and hydrophilic dextran molecules has been tracked in both healthy and inflamed skin using confocal laser scanning microscopy. The selective accumulation of the quantum dots was clearly observed in inflamed skin while hydrophilic dextran behaved similarly in both healthy and inflamed skin. The therapeutic potential for the transdermal delivery of peptide drugs through inflamed skin has been also tested in rats. Results revealed that the transdermal permeation of insulin and calcitonin was not significantly enhanced in dermatitis compared to healthy skin. On the other side, permeation through stripped skin was significantly higher. However, the effect was limited and shorter compared to the SC injection where t min was 0.5h and 2h with a 70% and 46% reduction in blood glucose levels for the stripped skin and the SC injection respectively. Similarly, t min was 4h and 8h with area under the curve of 161±65% and 350±97% for the stripped skin and the SC injection respectively. In conclusion, the changes in skin permeability accompanied with skin inflammation did not affect its permeability to peptide drugs. Our findings also underline that experiments with the tape stripped skin model as a surrogate for inflamed skin can risk misleading conclusions due to significant difference of skin permeability between the tape stripped skin and inflamed skin. Copyright © 2016 Elsevier B.V. All rights reserved.

Impact of food intake on the pharmacokinetics of first-line antituberculosis drugs in Taiwanese tuberculosis patients.

PubMed

Lin, Hsien-Chun; Yu, Ming-Chih; Liu, Hsing-Jin; Bai, Kuan-Jen

2014-05-01

Under the directly observed treatment, short course (DOTS) program, antituberculosis (anti-TB) medications were possibly taken at random time, regardless of whether it was prior to or after meals. This study was to evaluate the impact of food intake on pharmacokinetic profiles of first-line TB drugs in Taiwanese TB patients, as well as the relationship between drug levels and pharmacogenetics. This open-label, randomized, cross-over study included newly diagnosed Taiwanese TB patients treated between January 2010 and February 2011 at Taipei Medical University-Wan Fang Hospital. Rifater [a fixed-dose combination formulation of isoniazid (INH), rifampicin (RIF), and pyrazinamide (PZA)] and ethambutol (EMB) were given according to national TB guidelines. Blood samples were collected prior to and 1 hour, 2 hours, 4 hours, 6 hours, and 10 hours after dosing under fasting or postprandial conditions. Pharmacokinetic parameters of the maximum serum concentration (Cmax), time to Cmax, and area under the serum concentration-time curve from the beginning to the 10(th) hour (AUC0-10) were calculated. Sixteen TB patients were included and received anti-TB treatment under the DOTS program after discharge. The overall effects showed that food intake reduced the mean Cmax (INH: 40.6%, RIF: 40.2%, EMB 34.4%, PZA: 24.4%) and AUC0-10 (INH: 21.3%, RIF: 26.4%, EMB: 12.2%, PZA: 12.0%). Meanwhile, food increased the time to Cmax (INH: 78.1%, RIF: 151.3%, EMB: 41.4%, PZA: 148.9%). Significantly lower serum drug concentrations were observed under postprandial conditions than fasting conditions for INH, RIF, and PZA. The impact of taking random anti-TB drugs under the DOTS program instead of taking drugs regularly prior to meals requires further study. Copyright © 2014. Published by Elsevier B.V.

Biochemistry and biomedicine of quantum dots: from biodetection to bioimaging, drug discovery, diagnostics, and therapy.

PubMed

Yao, Jun; Li, Pingfan; Li, Lin; Yang, Mei

2018-07-01

According to recent research, nanotechnology based on quantum dots (QDs) has been widely applied in the field of bioimaging, drug delivery, and drug analysis. Therefore, it has become one of the major forces driving basic and applied research. The application of nanotechnology in bioimaging has been of concern. Through in vitro labeling, it was found that luminescent QDs possess many properties such as narrow emission, broad UV excitation, bright fluorescence, and high photostability. The QDs also show great potential in whole-body imaging. The QDs can be combined with biomolecules, and hence, they can be used for targeted drug delivery and diagnosis. The characteristics of QDs make them useful for application in pharmacy and pharmacology. This review focuses on various applications of QDs, especially in imaging, drug delivery, pharmaceutical analysis, photothermal therapy, biochips, and targeted surgery. Finally, conclusions are made by providing some critical challenges and a perspective of how this field can be expected to develop in the future. Quantum dots (QDs) is an emerging field of interdisciplinary subject that involves physics, chemistry, materialogy, biology, medicine, and so on. In addition, nanotechnology based on QDs has been applied in depth in biochemistry and biomedicine. Some forward-looking fields emphatically reflected in some extremely vital areas that possess inspiring potential applicable prospects, such as immunoassay, DNA analysis, biological monitoring, drug discovery, in vitro labelling, in vivo imaging, and tumor target are closely connected to human life and health and has been the top and forefront in science and technology to date. Furthermore, this review has not only involved the traditional biochemical detection but also particularly emphasized its potential applications in life science and biomedicine. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Cadmium-containing nanoparticles: Perspectives on pharmacology and toxicology of quantum dots

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

Rzigalinski, Beverly A.; Strobl, Jeannine S.

2009-08-01

The field of nanotechnology is rapidly expanding with the development of novel nanopharmaceuticals that have potential for revolutionizing medical treatment. The rapid pace of expansion in this field has exceeded the pace of pharmacological and toxicological research on the effects of nanoparticles in the biological environment. The development of cadmium-containing nanoparticles, known as quantum dots, show great promise for treatment and diagnosis of cancer and targeted drug delivery, due to their size-tunable fluorescence and ease of functionalization for tissue targeting. However, information on pharmacology and toxicology of quantum dots needs much further development, making it difficult to assess the risksmore » associated with this new nanotechnology. Further, nanotechnology poses yet another risk for toxic cadmium, which will now enter the biological realm in nano-form. In this review, we discuss cadmium-containing quantum dots and their physicochemical properties at the nano-scale. We summarize the existing work on pharmacology and toxicology of cadmium-containing quantum dots and discuss perspectives in their utility in disease treatment. Finally, we identify critical gaps in our knowledge of cadmium quantum dot toxicity, and how these gaps need to be assessed to enable quantum dot nanotechnology to transit safely from bench to bedside.« less

Impact of DOTS expansion on tuberculosis related outcomes and costs in Haiti.

PubMed

Jacquet, Vary; Morose, Willy; Schwartzman, Kevin; Oxlade, Olivia; Barr, Graham; Grimard, Franque; Menzies, Dick

2006-08-15

Implementation of the World Health Organization's DOTS strategy (Directly Observed Treatment Short-course therapy) can result in significant reduction in tuberculosis incidence. We estimated potential costs and benefits of DOTS expansion in Haiti from the government, and societal perspectives. Using decision analysis incorporating multiple Markov processes (Markov modelling), we compared expected tuberculosis morbidity, mortality and costs in Haiti with DOTS expansion to reach all of the country, and achieve WHO benchmarks, or if the current situation did not change. Probabilities of tuberculosis related outcomes were derived from the published literature. Government health expenditures, patient and family costs were measured in direct surveys in Haiti and expressed in 2003 US$. Starting in 2003, DOTS expansion in Haiti is anticipated to cost $4.2 million and result in 63,080 fewer tuberculosis cases, 53,120 fewer tuberculosis deaths, and net societal savings of $131 million, over 20 years. Current government spending for tuberculosis is high, relative to the per capita income, and would be only slightly lower with DOTS. Societal savings would begin within 4 years, and would be substantial in all scenarios considered, including higher HIV seroprevalence or drug resistance, unchanged incidence following DOTS expansion, or doubling of initial and ongoing costs for DOTS expansion. A modest investment for DOTS expansion in Haiti would provide considerable humanitarian benefit by reducing tuberculosis-related morbidity, mortality and costs for patients and their families. These benefits, together with projected minimal Haitian government savings, argue strongly for donor support for DOTS expansion.

A Meta-Analysis of Self-Administered vs Directly Observed Therapy Effect on Microbiologic Failure, Relapse, and Acquired Drug Resistance in Tuberculosis Patients

PubMed Central

Pasipanodya, Jotam G.; Gumbo, Tawanda

2013-01-01

Background Preclinical studies and Monte Carlo simulations have suggested that there is a relatively limited role of adherence in acquired drug resistance (ADR) and that very high levels of nonadherence are needed for therapy failure. We evaluated the superiority of directly observed therapy (DOT) for tuberculosis patients vs self-administered therapy (SAT) in decreasing ADR, microbiologic failure, and relapse in meta-analyses. Methods Prospective studies performed between 1965 and 2012 in which adult patients with microbiologically proven pulmonary Mycobacterium tuberculosis were separately assigned to either DOT or SAT as part of short-course chemotherapy were chosen. Endpoints were microbiologic failure, relapse, and ADR in patients on either DOT or SAT. Results Ten studies, 5 randomized and 5 observational, met selection criteria: 8774 patients were allocated to DOT and 3708 were allocated to SAT. For DOT vs SAT, the pooled risk difference for microbiologic failure was .0 (95% confidence interval [CI], −.01 to .01), for relapse .01 (95% CI, −.03 to .06), and for ADR 0.0 (95% CI, −0.01 to 0.01). The incidence rates for DOT vs SAT were 1.5% (95% CI, 1.3%–1.8%) vs 1.7% (95% CI, 1.2%–2.2%) for microbiologic failure, 3.7% (95% CI, 0.7%–17.6%) vs 2.3% (95% CI, 0.7%–7.2%) for relapse, and 1.5% (95% CI, 0.2%–9.90%) vs 0.9% (95% CI, 0.4%–2.3%) for ADR, respectively. There was no evidence of publication bias. Conclusions DOT was not significantly better than SAT in preventing microbiologic failure, relapse, or ADR, in evidence-based medicine. Resources should be shifted to identify other causes of poor microbiologic outcomes. PMID:23487389

Domestic returns from investment in the control of tuberculosis in other countries.

PubMed

Schwartzman, Kevin; Oxlade, Olivia; Barr, R Graham; Grimard, Franque; Acosta, Ivelisse; Baez, Jeannette; Ferreira, Elizabeth; Melgen, Ricardo Elías; Morose, Willy; Salgado, Arturo Cruz; Jacquet, Vary; Maloney, Susan; Laserson, Kayla; Mendez, Ariel Pablos; Menzies, Dick

2005-09-08

We hypothesized that investments to improve the control of tuberculosis in selected high-incidence countries would prove to be cost saving for the United States by reducing the incidence of the disease among migrants. Using decision analysis, we estimated tuberculosis-related morbidity, mortality, and costs among legal immigrants and refugees, undocumented migrants, and temporary visitors from Mexico after their entry into the United States. We assessed the current strategy of radiographic screening of legal immigrants plus current tuberculosis-control programs alone and with the addition of either U.S.-funded expansion of the strategy of directly observed treatment, short course (DOTS), in Mexico or tuberculin skin testing to screen legal immigrants from Mexico. We also examined tuberculosis-related outcomes among migrants from Haiti and the Dominican Republic using the same three strategies. As compared with the current strategy, expanding the DOTS program in Mexico at a cost to the United States of 34.9 million dollars would result in 2591 fewer cases of tuberculosis in the United States, with 349 fewer deaths from the disease and net discounted savings of 108 million dollars over a 20-year period. Adding tuberculin skin testing to radiographic screening of legal immigrants from Mexico would result in 401 fewer cases of tuberculosis in the United States but would cost an additional 329 million dollars. Expansion of the DOTS program would remain cost saving even if the initial investment were doubled, if the United States paid for all antituberculosis drugs in Mexico, or if the decline in the incidence of tuberculosis in Mexico was less than projected. A 9.4 million dollars investment to expand the DOTS program in Haiti and the Dominican Republic would result in net U.S. savings of 20 million dollars over a 20-year period. U.S.-funded efforts to expand the DOTS program in Mexico, Haiti, and the Dominican Republic could reduce tuberculosis-related morbidity and mortality among migrants to the United States, producing net cost savings for the United States. Copyright 2005 Massachusetts Medical Society.

[Analysis on workload for hospital DOTS service].

PubMed

Nagata, Yoko; Urakawa, Minako; Kobayashi, Noriko; Kato, Seiya

2014-04-01

A directly observed treatment short course (DOTS) trial was launched in Japan in the late 1990s and targeted patients with social depression at urban areas. Based on these findings, the Ministry of Health, Labour and Welfare established the Japanese DOTS Strategy in 2003, which is a comprehensive support service ensuring the adherence of tuberculosis patients to drug administration. DOTS services are initially provided at the hospital to patients with infectious tuberculosis who are hospitalized according to the Infectious Diseases Control Law. After being discharged from the hospital, the patients are referred to a public health center. However, a survey conducted in 2008 indicated that all the patients do not receive appropriate DOTS services at some hospitals. In the present study, we aimed to evaluate the protocols and workload of DOTS at hospitals that are actively involved in tuberculosis medical practice, including DOTS, to assess whether the hospital DOTS services were adequate. We reviewed a series of articles on hospital DOTS from a Japanese journal on nursing for tuberculosis patients and identified 25 activities regarding the hospital DOTS service. These 25 items were then classified into 3 categories: health education to patients, support for adherence, and coordination with the health center. In total, 20 hospitals that had > 20 authorized tuberculosis beds were selected--while considering the geographical balance, schedule of this survey, etc.--from 33 hospitals where an ex-trainee of the tuberculosis control expert training program in the Research Institute of Tuberculosis (RIT) was working and 20 hospitals that had collaborated with our previous survey on tuberculosis medical facilities. All the staff associated with the DOTS service were asked to record the total working time as well as the time spent for each activity. The data were collected and analyzed at the RIT. The working times for each activity of the DOTS service for nurses, pharmacists, ward clerks, head nurses, and doctors were 100, 90, 87, 86, and 63 min, respectively. For other professions, including medical social workers, nursing aids, nutritionists, and physical therapists, the working times for each activity of the DOTS service were 31, 18, 10, and 8 min, respectively. The professionals who spent a longer time on health education, support for patient adherence, and coordination with the health center were pharmacists, doctors, and head nurses; nurses, pharmacists, and doctors; and head nurses, doctors, and ward clerks, respectively. Aging of tuberculosis patients was associated with problems on adherence in many patients, including patients who were not suited for a standard regimen, patients whose activity of daily life had deteriorated due to senile dementia, patients with diabetes mellitus, etc. Smoking cessation and mental care for cases of multi-drug resistant disease are new challenges in tuberculosis patient care. The present study clearly indicated that activities including patient education, support for patient adherence, and coordination with the health center--essential components of the hospital DOTS service according to the Japanese DOTS Strategy--were performed by a team of professionals including doctors, nurses, pharmacists, medical social workers, etc., depending on the features and roles that they serve and the needs of each patient. For good practice of hospital DOTS, it is essential to not only provide DOTS, but also effectively provide individual or group health education and coordinate with health centers, thus aiming towards a better community DOTS service after patient discharge.

Quick test for percent of deleterious material.

DOT National Transportation Integrated Search

2009-08-28

The Missouri Department of Transportation (MoDOT) is considering the replacement of its deleterious : materials test method (TM-71) with test methods that are more objective. MoDOT contracted with the Missouri : University of Science and Technology (...

Doxorubicin loaded carboxymethyl cellulose/graphene quantum dot nanocomposite hydrogel films as a potential anticancer drug delivery system.

PubMed

Javanbakht, Siamak; Namazi, Hassan

2018-06-01

Creating anticancer properties in the hydrogel film could make it as a candidate for treating cancer tissues. In this work, a novel hydrogel nanocomposite films with anticancer properties were designed via incorporation of graphene quantum dot (GQD) as a nanoparticle into carboxymethyl cellulose (CMC) hydrogel and using doxorubicin (DOX) as drug model with broad-spectrum anticancer properties. Drug release studies carried out at two different pHs and the MTT assay was evaluated for DOX-loaded CMC/GQD nanocomposite hydrogel films against blood cancer cells (K562). The prepared nanocomposite hydrogel films were characterized using Fourier transform infrared (FT-IR), UV-Vis spectroscopy, scanning electron microscopy (SEM), permeability and mechanical properties. The prepared CMC/GQD nanocomposite hydrogel films showed an improvement in vitro swelling, degradation, water vapor permeability and pH-sensitive drug delivery properties along with not significant toxicity against blood cancer cells (K562). According to the obtained results, this nanocomposite hydrogel films can be proposed to use as an anticancer film and drug delivery system. Copyright © 2018 Elsevier B.V. All rights reserved.

The design organization test: further demonstration of reliability and validity as a brief measure of visuospatial ability.

PubMed

Killgore, William D S; Gogel, Hannah

2014-01-01

Neuropsychological assessments are frequently time-consuming and fatiguing for patients. Brief screening evaluations may reduce test duration and allow more efficient use of time by permitting greater attention toward neuropsychological domains showing probable deficits. The Design Organization Test (DOT) was initially developed as a 2-min paper-and-pencil alternative for the Block Design (BD) subtest of the Wechsler scales. Although initially validated for clinical neurologic patients, we sought to further establish the reliability and validity of this test in a healthy, more diverse population. Two alternate versions of the DOT and the Wechsler Abbreviated Scale of Intelligence (WASI) were administered to 61 healthy adult participants. The DOT showed high alternate forms reliability (r = .90-.92), and the two versions yielded equivalent levels of performance. The DOT was highly correlated with BD (r = .76-.79) and was significantly correlated with all subscales of the WASI. The DOT proved useful when used in lieu of BD in the calculation of WASI IQ scores. Findings support the reliability and validity of the DOT as a measure of visuospatial ability and suggest its potential worth as an efficient estimate of intellectual functioning in situations where lengthier tests may be inappropriate or unfeasible.

Validity of the Dictionary of Occupational Titles for Assessing Upper Extremity Work Demands

PubMed Central

Opsteegh, Lonneke; Soer, Remko; Reinders-Messelink, Heleen A.; Reneman, Michiel F.; van der Sluis, Corry K.

2010-01-01

Objectives The Dictionary of Occupational Titles (DOT) is used in vocational rehabilitation to guide decisions about the ability of a person with activity limitations to perform activities at work. The DOT has categorized physical work demands in five categories. The validity of this categorization is unknown. Aim of this study was to investigate whether the DOT could be used validly to guide decisions for patients with injuries to the upper extremities. Four hypotheses were tested. Methods A database including 701 healthy workers was used. All subjects filled out the Dutch Musculoskeletal Questionnaire, from which an Upper Extremity Work Demands score (UEWD) was derived. First, relation between the DOT-categories and UEWD-score was analysed using Spearman correlations. Second, variance of the UEWD-score in occupational groups was tested by visually inspecting boxplots and assessing kurtosis of the distribution. Third, it was investigated whether occupations classified in one DOT-category, could significantly differ on UEWD-scores. Fourth, it was investigated whether occupations in different DOT-categories could have similar UEWD-scores using Mann Whitney U-tests (MWU). Results Relation between the DOT-categories and the UEWD-score was weak (rsp = 0.40; p<.01). Overlap between categories was found. Kurtosis exceeded ±1.0 in 3 occupational groups, indicating large variance. UEWD-scores were significantly different within one DOT-category (MWU = 1.500; p<.001). UEWD scores between DOT-categories were not significantly different (MWU = 203.000; p = .49). Conclusion All four hypotheses could not be rejected. The DOT appears to be invalid for assessing upper extremity work demands. PMID:21151934

Phototoxicity free quantum dot-based niosome formulation for controlled drug release and its monitoring

NASA Astrophysics Data System (ADS)

Kumar, Sunil; Kang, T. W.; Bala, Suman; Kamboj, Sunil; Jeon, H. C.

2018-04-01

A novel niosomes-based system composed of Hypromellose (HPMC) functionalized fluorescent, biocompatible ZnS:Mn quantum dots (QDs), and anti-HIV drug Tenofovir disoproxil fumarate (TDF) was designed. An appropriate ratio of surfactant Sorbitan Monostearate (SPAN-60) and cholesterol was used to obtain an optimal entrapment efficiency. Initially, after observing the successful interaction of HPMC with SPAN-60, the noisome formulation including (QDs + drug) and HPMC-coated QDs was synthesized by a wet chemical route and characterized by X-ray diffraction (XRD), Transmission electron microscope (TEM) and Selected Electron Diffraction (SAED). Secondly, (QDs + drug) loaded niosome formulations were studied by varying the ratio of SPAN-60 and cholesterol. Multiple studies were done to characterize the shape, size, viscosity, colloidal stability, and entrapment efficiency of (QDs + drug) loaded niosomes. Lastly, pH-dependent (QDs + drug) release profiles were studied by a spectroscopic technique considering the pH of the human gastrointestinal region to obtain the formulation stability of (QDs + drug) release from the niosome vesicles. These studies also include pH-dependent photo-stability measurements based on laser-induced multiphoton excitation technique in the Infrared region. The multiphoton time-resolved studies were completed to avoid the UV induced phototoxicity in the drug delivery modules. Current studies on the formulation of niosomes-based (QDs + drug) system laid a foundation to make a complete phototoxicity free system for tracking controlled drug release and its imaging.

Highly fluorescent and morphology-controllable graphene quantum dots-chitosan hybrid xerogels for in vivo imaging and pH-sensitive drug carrier.

PubMed

Lv, Ouyang; Tao, Yongxin; Qin, Yong; Chen, Chuanxiang; Pan, Yan; Deng, Linhong; Liu, Li; Kong, Yong

2016-10-01

Highly fluorescent graphene quantum dots (GQDs)-chitosan (CS) hybrid xerogels (GQDs-CS) were facilely synthesized, and the morphology of GQDs-CS was controllable by varying the content of GQDs in the xerogel. The GQDs-CS exhibited a porous and three-dimensional (3D) network structure when the content of GQDs reached 43% (wt%) in the xerogel, which was beneficial for drug loading and sustained release. The as-prepared GQDs-CS could also be applied for in vivo imaging since it showed strong blue, green and red luminescence under excitation of varying wavelengths. Moreover, the pH-induced protonation/deprotonation of the -NH2 groups on CS chains can result in a pH-dependent drug delivery behavior of the GQDs-CS hybrid xerogel. Copyright © 2016 Elsevier B.V. All rights reserved.

Improved Low Temperature Performance of Supercapacitors

NASA Technical Reports Server (NTRS)

Brandon, Erik J.; West, William C.; Smart, Marshall C.; Gnanaraj, Joe

2013-01-01

Low temperature double-layer capacitor operation enabled by: - Base acetonitrile / TEATFB salt formulation - Addition of low melting point formates, esters and cyclic ethers center dot Key electrolyte design factors: - Volume of co-solvent - Concentration of salt center dot Capacity increased through higher capacity electrodes: - Zeolite templated carbons - Asymmetric cell designs center dot Continuing efforts - Improve asymmetric cell performance at low temperature - Cycle life testing Motivation center dot Benchmark performance of commercial cells center dot Approaches for designing low temperature systems - Symmetric cells (activated carbon electrodes) - Symmetric cells (zeolite templated carbon electrodes) - Asymmetric cells (lithium titanate/activated carbon electrodes) center dot Experimental results center dot Summary

Controlling multidrug-resistant tuberculosis and access to expensive drugs: a rational framework.

PubMed Central

Pablos-Mendez, Ariel; Gowda, Deepthiman K.; Frieden, Thomas R.

2002-01-01

The emergence and spread of multidrug-resistant tuberculosis (MDR-TB), i.e. involving resistance to at least isoniazid and rifampicin, could threaten the control of TB globally. Controversy has emerged about the best way of confronting MDR-TB in settings with very limited resources. In 1999, the World Health Organization (WHO) created a working group on DOTS-Plus, an initiative exploring the programmatic feasibility and cost-effectiveness of treating MDR-TB in low-income and middle-income countries, in order to consider the management of MDR-TB under programme conditions. The challenges of implementation have proved more daunting than those of access to second-line drugs, the prices of which are dropping. Using data from the WHO/International Union Against Tuberculosis and Lung Disease surveillance project, we have grouped countries according to the proportion of TB patients completing treatment successfully and the level of MDR-TB among previously untreated patients. The resulting matrix provides a reasonable framework for deciding whether to use second-line drugs in a national programme. Countries in which the treatment success rate, i.e. the proportion of new patients who complete the scheduled treatment, irrespective of whether bacteriological cure is documented, is below 70% should give the highest priority to introducing or improving DOTS, the five-point TB control strategy recommended by WHO and the International Union Against Tuberculosis and Lung Disease. A poorly functioning programme can create MDR-TB much faster than it can be treated, even if unlimited resources are available. There is no single prescription for controlling MDR-TB but the various tools available should be applied wisely. Firstly, good DOTS and infection control; then appropriate use of second-line drug treatment. The interval between the two depends on the local context and resources. As funds are allocated to treat MDR-TB, human and financial resources should be increased to expand DOTS worldwide. PMID:12132008

Bioresponsive carbon nano-gated multifunctional mesoporous silica for cancer theranostics

NASA Astrophysics Data System (ADS)

Prasad, Rajendra; Aiyer, Sandhya; Chauhan, Deepak S.; Srivastava, Rohit; Selvaraj, Kaliaperumal

2016-02-01

Designing bioresponsive nanocarriers for controlled and efficient intracellular drug release for cancer therapy is a major thrust area in nanomedicine. With recent recognition by the US FDA as a safe material for human trials, mesoporous silica nanoparticles (MSNPs) are being extensively explored as promising theranostic agents. Green fluorescent carbon quantum dots (CQDs), though known as possible alternatives for their more toxic and relatively less efficient predecessors, are less known as gate keepers for drug release control. We report for the first time an efficient bioresponse of CQDs when judiciously designed using glutathione cleavable (redox responsive) disulphide bonds. When the anticancer drug doxorubicin loaded MSNPs are capped with these CQDs, they display promising drug release control on exposure to a mimicked intracellular cancer environment. Their dual functionality is well established with good control on preventing the premature release and exceptional bio-imaging of HeLa cancer cells. Fluorescence images prove selective targeting of HeLa cells by overexpression of folate receptors from the surface functionalised folic acid ligand. Extensive characterisation using XRD, TEM, BET analysis, drug loading tests, drug release kinetics, MTT assay and fluoroscence cell imaging helps in understanding the multifunctionalities of the successful design, extending its scope with exciting prospects towards non-invasive targeted drug delivery and bio-imaging for effective cancer diagnosis and treatment.Designing bioresponsive nanocarriers for controlled and efficient intracellular drug release for cancer therapy is a major thrust area in nanomedicine. With recent recognition by the US FDA as a safe material for human trials, mesoporous silica nanoparticles (MSNPs) are being extensively explored as promising theranostic agents. Green fluorescent carbon quantum dots (CQDs), though known as possible alternatives for their more toxic and relatively less efficient predecessors, are less known as gate keepers for drug release control. We report for the first time an efficient bioresponse of CQDs when judiciously designed using glutathione cleavable (redox responsive) disulphide bonds. When the anticancer drug doxorubicin loaded MSNPs are capped with these CQDs, they display promising drug release control on exposure to a mimicked intracellular cancer environment. Their dual functionality is well established with good control on preventing the premature release and exceptional bio-imaging of HeLa cancer cells. Fluorescence images prove selective targeting of HeLa cells by overexpression of folate receptors from the surface functionalised folic acid ligand. Extensive characterisation using XRD, TEM, BET analysis, drug loading tests, drug release kinetics, MTT assay and fluoroscence cell imaging helps in understanding the multifunctionalities of the successful design, extending its scope with exciting prospects towards non-invasive targeted drug delivery and bio-imaging for effective cancer diagnosis and treatment. Electronic supplementary information (ESI) available: Size distribution histograms, PL spectra of CQDs at different pH values and at different excitation wavelengths, TEM images and the FTIR spectrum. See DOI: 10.1039/c5nr06756a

A Novel Quantum Dots-Based Point of Care Test for Syphilis

NASA Astrophysics Data System (ADS)

Yang, Hao; Li, Ding; He, Rong; Guo, Qin; Wang, Kan; Zhang, Xueqing; Huang, Peng; Cui, Daxiang

2010-05-01

One-step lateral flow test is recommended as the first line screening of syphilis for primary healthcare settings in developing countries. However, it generally shows low sensitivity. We describe here the development of a novel fluorescent POC (Point Of Care) test method to be used for screening for syphilis. The method was designed to combine the rapidness of lateral flow test and sensitiveness of fluorescent method. 50 syphilis-positive specimens and 50 healthy specimens conformed by Treponema pallidum particle agglutination (TPPA) were tested with Quantum Dot-labeled and colloidal gold-labeled lateral flow test strips, respectively. The results showed that both sensitivity and specificity of the quantum dots-based method reached up to 100% (95% confidence interval [CI], 91-100%), while those of the colloidal gold-based method were 82% (95% CI, 68-91%) and 100% (95% CI, 91-100%), respectively. In addition, the naked-eye detection limit of quantum dot-based method could achieve 2 ng/ml of anti-TP47 polyclonal antibodies purified by affinity chromatography with TP47 antigen, which was tenfold higher than that of colloidal gold-based method. In conclusion, the quantum dots were found to be suitable for labels of lateral flow test strip. Its ease of use, sensitiveness and low cost make it well-suited for population-based on-the-site syphilis screening.

Metallic nanoparticles and their medicinal potential. Part II: aluminosilicates, nanobiomagnets, quantum dots and cochleates.

PubMed

Loomba, Leena; Scarabelli, Tiziano

2013-09-01

Metallic miniaturization techniques have taken metals to nanoscale size where they can display fascinating properties and their potential applications in medicine. In recent years, metal nanoparticles such as aluminium, silicon, iron, cadmium, selenium, indium and calcium, which find their presence in aluminosilicates, nanobiomagnets, quantum dots (Q-dots) and cochleates, have caught attention of medical industries. The increasing impact of metallic nanoparticles in life sciences has significantly advanced the production techniques for these nanoparticles. In this Review, the various methods for the synthesis of nanoparticles are outlined, followed by their physicochemical properties, some recent applications in wound healing, diagnostic imaging, biosensing, assay labeling, antimicrobial activity, cancer therapy and drug delivery are listed, and finally their toxicological impacts are revised. The first half of this article describes the medicinal uses of two noble nanoparticles - gold and silver. This Review provides further information on the ability of aluminum, silicon, iron, selenium, indium, calcium and zinc to be used as nanoparticles in biomedical sciences. Aluminosilicates find their utility in wound healing and antibacterial growth. Iron-oxide nanoparticles enhance the properties of MRI contrast agents and are also used as biomagnets. Cadmium, selenium, tellurium and indium form the core nanostructures of tiny Q-dots used in cellular assay labeling, high-resolution cell imaging and biosensing. Cochleates have the bivalent nano ions calcium, magnesium or zinc imbedded in their structures and are considered to be highly effective agents for drug and gene delivery. The aluminosilicates, nanobiomagnets, Q-dots and cochleates are discussed in the light of their properties, synthesis and utility.

Multifunctional nanomaterials for advanced molecular imaging and cancer therapy

NASA Astrophysics Data System (ADS)

Subramaniam, Prasad

Nanotechnology offers tremendous potential for use in biomedical applications, including cancer and stem cell imaging, disease diagnosis and drug delivery. The development of nanosystems has aided in understanding the molecular mechanisms of many diseases and permitted the controlled nanoscale manipulation of biological phenomena. In recent years, many studies have focused on the use of several kinds of nanomaterials for cancer and stem cell imaging and also for the delivery of anticancer therapeutics to tumor cells. However, the proper diagnosis and treatment of aggressive tumors such as brain and breast cancer requires highly sensitive diagnostic agents, in addition to the ability to deliver multiple therapeutics using a single platform to the target cells. Addressing these challenges, novel multifunctional nanomaterial-based platforms that incorporate multiple therapeutic and diagnostic agents, with superior molecular imaging and targeting capabilities, has been presented in this work. The initial part of this work presents the development of novel nanomaterials with superior optical properties for efficiently delivering soluble cues such as small interfering RNA (siRNA) into brain cancer cells with minimal toxicity. Specifically, this section details the development of non-toxic quantums dots for the imaging and delivery of siRNA into brain cancer and mesenchymal stem cells, with the hope of using these quantum dots as multiplexed imaging and delivery vehicles. The use of these quantum dots could overcome the toxicity issues associated with the use of conventional quantum dots, enabled the imaging of brain cancer and stem cells with high efficiency and allowed for the delivery of siRNA to knockdown the target oncogene in brain cancer cells. The latter part of this thesis details the development of nanomaterial-based drug delivery platforms for the co-delivery of multiple anticancer drugs to brain tumor cells. In particular, this part of the thesis focuses on the synthesis and use of a biodegradable dendritic polypeptide-based nanocarrier for the delivery of multiple anticancer drugs and siRNA to brain tumor cells. The co-delivery of important anticancer agents using a single platform was shown to increase the efficacy of the drugs manyfold, ensuring the cancer cell-specific delivery and minimizing dose limiting toxicities of the individual drugs. This would be of immense importance when used in vivo.

Thermal performance characterization of residential wall systems using a calibrated hot box with airflow induced by differential pressures

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

Jones, D.C.; Ober, D.G.; Goodrow, J.T.

1995-09-01

ASTM E 283 ad ASTM E 1424 in conjunction with ASTM C 976 were used to study the effect of airflow on thermal performance of the wall. A typical residential 2 {times} 4 stud wall was constructed and placed on top of a subfloor, making a 2.44 {times} 2.74 m (8 by 9 ft) test specimen. This base wall assembly was then covered with two types of XPS sheathing, various housewraps, a 15{number_sign} felt, and a polyethylene vapor retarder film in 40 different configurations and tested individually per ASTM E 283 and per ASTM C 976. For 24 of themore » 40 C 976 tests, a differential pressure was induced across the test wall as per and ASTM E 1424. Airflows ranged from undetectable airflow at 0 {center_dot} Pa {Delta}P to 1.63 L/s {center_dot} m{sup 2} for the base wall assembly alone. Difference in airflow resistance performance between the ASTM E 283 and ASTM E 1424 test methods were noted. Thermal testing results incorporating both ASTM C 976 and ASTM E 1424 for tests 1--28 produced apparent thermal conductances (C-values) in the range of 0.40 W/m{sup 2} {center_dot} K for a nondetectable airflow level to 1.81 W/m{sup 2} {center_dot} K for an airflow of 1.53 L/s {center_dot} m{sup 2} for the base wall assembly alone with a 20-Pa {Delta}P. The calculated C-value for this base wall assembly was 0.40 W/m{sup 2} {center_dot} K. Test results reveal that airflow rates as low as 0.2 L/s {center_dot} m{sup 2} could produce a 46% increase in apparent C-value. Similar thermal performance differences were revealed when thicker shiplap XPS sheathing was used. Tests were also conducted using an Air-Tight Drywall configuration showing the effect of wind washing on thermal performance. By sealing the gypsum drywall on the base wall assembly tested, the apparent C-value, when exposed to a 12.5 Pa wind pressure, was found to be equivalent to a base wall assembly configuration which allows 0.15 L/s {center_dot} m{sup 2} airflow to penetrate completely through.« less

Synthesis, characterization and target protein binding of drug-conjugated quantum dots in vitro and in living cells

NASA Astrophysics Data System (ADS)

Choi, Youngseon; Kim, Minjung; Cho, Yoojin; Yun, Eunsuk; Song, Rita

2013-02-01

Elucidation of unknown target proteins of a drug is of great importance in understanding cell biology and drug discovery. There have been extensive studies to discover and identify target proteins in the cell. Visualization of targets using drug-conjugated probes has been an important approach to gathering mechanistic information of drug action at the cellular level. As quantum dot (QD) nanocrystals have attracted much attention as a fluorescent probe in the bioimaging area, we prepared drug-conjugated QD to explore the potential of target discovery. As a model drug, we selected a well-known anticancer drug, methotrexate (MTX), which has been known to target dihydrofolate reductase (DHFR) with high affinity binding (Kd = 0.54 nM). MTX molecules were covalently attached to amino-PEG-polymer-coated QDs. Specific interactions of MTX-conjugated QDs with DHFR were identified using agarose gel electrophoresis and fluorescence microscopy. Cellular uptake of the MTX-conjugated QDs in living CHO cells was investigated with regard to their localization and distribution pattern. MTX-QD was found to be internalized into the cells via caveolae-medicated endocytosis without significant sequestration in endosomes. A colocalization experiment of the MTX-QD conjugate with antiDHFR-TAT-QD also confirmed that MTX-QD binds to the target DHFR. This study showed the potential of the drug-QD conjugate to identify or visualize drug-target interactions in the cell, which is currently of great importance in the area of drug discovery and chemical biology.

48 CFR 1223.7000 - Contract clauses.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SOCIOECONOMIC PROGRAMS ENVIRONMENT, ENERGY AND WATER EFFICIENCY, RENEWABLE ENERGY TECHNOLOGIES, OCCUPATIONAL SAFETY, AND DRUG-FREE WORKPLACE Safety Requirements for Selected DOT Contracts 1223.7000 Contract clauses...

Updating the Skating Multistage Aerobic Test and Correction for V[Combining Dot Above]O2max Prediction Using a New Skating Economy Index in Elite Youth Ice Hockey Players.

PubMed

Allisse, Maxime; Bui, Hung Tien; Léger, Luc; Comtois, Alain-Steve; Leone, Mario

2018-05-07

Allisse, M, Bui, HT, Léger, L, Comtois, A-S, and Leone, M. Updating the skating multistage aerobic test and correction for V[Combining Dot Above]O2max prediction using a new skating economy index in elite youth ice hockey players. J Strength Cond Res XX(X): 000-000, 2018-A number of field tests, including the skating multistage aerobic test (SMAT), have been developed to predict V[Combining Dot Above]O2max in ice hockey players. The SMAT, like most field tests, assumes that participants who reach a given stage have the same oxygen uptake, which is not usually true. Thus, the objectives of this research are to update the V[Combining Dot Above]O2 values during the SMAT using a portable breath-by-breath metabolic analyzer and to propose a simple index of skating economy to improve the prediction of oxygen uptake. Twenty-six elite hockey players (age 15.8 ± 1.3 years) participated in this study. The oxygen uptake was assessed using a portable metabolic analyzer (K4b) during an on-ice maximal shuttle skate test. To develop an index of skating economy called the skating stride index (SSI), the number of skating strides was compiled for each stage of the test. The SMAT enabled the prediction of the V[Combining Dot Above]O2max (ml·kg·min) from the maximal velocity (m·s) and the SSI (skating strides·kg) using the following regression equation: V[Combining Dot Above]O2max = (14.94 × maximal velocity) + (3.68 × SSI) - 24.98 (r = 0.95, SEE = 1.92). This research allowed for the update of the oxygen uptake values of the SMAT and proposed a simple measure of skating efficiency for a more accurate evaluation of V[Combining Dot Above]O2max in elite youth hockey players. By comparing the highest and lowest observed SSI scores in our sample, it was noted that the V[Combining Dot Above]O2 values can vary by up to 5 ml·kg·min. Our results suggest that skating economy should be included in the prediction of V[Combining Dot Above]O2max to improve prediction accuracy.

Community-based directly observed treatment for TB patients to improve HIV services: a cross-sectional study in a South African province.

PubMed

Howell, Embry M; Kigozi, N Gladys; Heunis, J Christo

2018-04-07

There is uncertainty about how directly observed treatment (DOT) support for tuberculosis (TB) can be delivered most effectively and how DOT support can simultaneously be used to strengthen human immunodeficiency virus (HIV) prevention and control among TB patients. This study describes how DOT support by community health workers (CHWs) was used in four municipalities in the Free State province - a high TB/HIV burden, poorly-resourced setting - to provide HIV outreach, referrals, and health education for TB patients. The study was part of a larger cross-sectional study of HIV counselling and testing (HCT) among 1101 randomly-selected TB patients registered at 40 primary health care (PHC) facilities (clinics and community health centres) across small town/rural and large town/urban settings. Univariate analysis of percentages, chi-square tests and t-tests for difference in means were used to describe differences between the types of TB treatment support and patient characteristics, as well as the types of - and patient satisfaction with - HIV information and referrals received from various types of treatment supporters including home-based DOT supporters, clinic-based DOT supporters or support from family/friends/employers. Multivariate logistic regression was used to predict the likelihood of not having receiving home-based DOT and of never having received HIV counselling. The independent variables include poverty-related health and socio-economic risk factors for poor outcomes. Statistical significance is shown using a 95% confidence interval and a 0.05 p-value. Despite the fact that DOT support for all TB patients was the goal of South African health policy at the time (2012), most TB patients were not receiving formal DOT support. Only 155 (14.1%) were receiving home-based DOT, while 114 (10.4%) received clinic-based DOT. TB patients receiving home-based DOT reported higher rates of HIV counselling than other patients. Public health providers should train DOT supporters to provide HIV prevention and target DOT to those at greatest risk of HIV, particularly those at greatest socio-economic risk.

49 CFR 40.23 - What actions do employers take after receiving verified test results?

Code of Federal Regulations, 2011 CFR

2011-10-01

...., random test, post-accident test) and DOT Agency (e.g., check DOT and FMCSA) as for the original... verified test results? 40.23 Section 40.23 Transportation Office of the Secretary of Transportation... What actions do employers take after receiving verified test results? (a) As an employer who receives a...

49 CFR 40.23 - What actions do employers take after receiving verified test results?

Code of Federal Regulations, 2013 CFR

2013-10-01

...., random test, post-accident test) and DOT Agency (e.g., check DOT and FMCSA) as for the original... verified test results? 40.23 Section 40.23 Transportation Office of the Secretary of Transportation... What actions do employers take after receiving verified test results? (a) As an employer who receives a...

49 CFR 40.23 - What actions do employers take after receiving verified test results?

Code of Federal Regulations, 2012 CFR

2012-10-01

...., random test, post-accident test) and DOT Agency (e.g., check DOT and FMCSA) as for the original... verified test results? 40.23 Section 40.23 Transportation Office of the Secretary of Transportation... What actions do employers take after receiving verified test results? (a) As an employer who receives a...

49 CFR 40.23 - What actions do employers take after receiving verified test results?

Code of Federal Regulations, 2014 CFR

2014-10-01

...., random test, post-accident test) and DOT Agency (e.g., check DOT and FMCSA) as for the original... an employer who receives a cancelled test result when a negative result is required (e.g., pre... verified test results? 40.23 Section 40.23 Transportation Office of the Secretary of Transportation...

49 CFR 40.23 - What actions do employers take after receiving verified test results?

Code of Federal Regulations, 2010 CFR

2010-10-01

...., random test, post-accident test) and DOT Agency (e.g., check DOT and FMCSA) as for the original... an employer who receives a cancelled test result when a negative result is required (e.g., pre... verified test results? 40.23 Section 40.23 Transportation Office of the Secretary of Transportation...

Fluorescent carbon dots from mono- and polysaccharides: synthesis, properties and applications

PubMed Central

Hill, Stephen

2017-01-01

Fluorescent carbon dots (FCDs) are an emerging class of nanomaterials made from carbon sources that have been hailed as potential non-toxic replacements to traditional semiconductor quantum dots (QDs). Particularly in the areas of live imaging and drug delivery, due to their water solubility, low toxicity and photo- and chemical stability. Carbohydrates are readily available chiral biomolecules in nature which offer an attractive and cheap starting material from which to synthesise FCDs with distinct features and interesting applications. This mini-review article will cover the progress in the development of FCDs prepared from carbohydrate sources with an emphasis on their synthesis, functionalization and technical applications, including discussions on current challenges. PMID:28503203

Rapid and Sensitive Detection of Protein Biomarker Using a Portable Fluorescence Biosensor based on Quantum Dots and a Lateral Flow Test Strip

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

Li, Zhaohui; Wang, Ying; Wang, Jun

2010-08-15

A portable fluorescence biosensor with rapid and ultrasensitive response for trace protein has been built up with quantum dots and lateral flow test strip. The superior signal brightness and high photostability of quantum dots are combined with the promising advantages of lateral flow test strip and resulted in high sensitivity, selectivity and speedy for protein detection. Nitrated ceruloplasmin, a significant biomarker for cardiovascular disease, lung cancer and stress response to smoking, was used as model protein to demonstrate the good performances of this proposed Qdot-based lateral flow test strip. Quantitative detection of nitrated ceruloplasmin was realized by recording the fluorescencemore » intensity of quantum dots captured on the test line. Under optimal conditions, this portable fluorescence biosensor displays rapid responses for nitrated ceruloplasmin in wide dynamic range with a detection limit of 0.1ng/mL (S/N=3). Furthermore, the biosensor was successfully utilized for spiked human plasma sample detection with the concentration as low as 1ng/mL. The results demonstrate that the quantum dot-based lateral flow test strip is capable for rapid, sensitive, and quantitative detection of nitrated ceruloplasmin and hold a great promise for point-of-care and in field analysis of other protein biomarkers.« less

Sunlight-driven photocatalytic degradation of non-steroidal anti-inflammatory drug based on TiO₂ quantum dots.

PubMed

Kaur, Amandeep; Umar, Ahmad; Kansal, Sushil Kumar

2015-12-01

This paper reports the facile synthesis, characterization and solar-light driven photocatalytic degradation of TiO2 quantum dots (QDs). The TiO2 QDs were synthesized by a facile ultrasonic-assisted hydrothermal process and characterized in terms of their structural, morphological, optical and photocatalytic properties. The detailed studies confirmed that the prepared QDs are well-crystalline, grown in high density and exhibiting good optical properties. Further, the prepared QDs were efficiently used as effective photocatalyst for the sun-light driven photocatalytic degradation of ketorolac tromethamine, a well-known non-steroidal anti-inflammatory drug (NSAID). To optimize the photocatalytic degradation conditions, various dose-dependent, pH-dependent, and initial drug-concentration dependent experiments were performed. The detailed solar-light driven photocatalytic experiments revealed that ∼99% photodegradation of ketorolac tromethamine drug solution (10 mg L(-1)) was observed with optimized amount of TiO2 QDs and pH (0.5 g L(-1) and 4.4, respectively) under solar-light irradiations. The observed results demonstrate that simply synthesized TiO2 QDs can efficiently be used for the solar-light driven photocatalytic degradation of harmful drugs and chemicals. Copyright © 2015 Elsevier Inc. All rights reserved.

49 CFR 40.225 - What form is used for an alcohol test?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false What form is used for an alcohol test? 40.225... Testing § 40.225 What form is used for an alcohol test? (a) The DOT Alcohol Testing Form (ATF) must be used for every DOT alcohol test. The ATF must be a three-part carbonless manifold form. The ATF is...

49 CFR 40.225 - What form is used for an alcohol test?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 1 2012-10-01 2012-10-01 false What form is used for an alcohol test? 40.225... Testing § 40.225 What form is used for an alcohol test? (a) The DOT Alcohol Testing Form (ATF) must be used for every DOT alcohol test. The ATF must be a three-part carbonless manifold form. The ATF is...

49 CFR 40.225 - What form is used for an alcohol test?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 1 2013-10-01 2013-10-01 false What form is used for an alcohol test? 40.225... Testing § 40.225 What form is used for an alcohol test? (a) The DOT Alcohol Testing Form (ATF) must be used for every DOT alcohol test. The ATF must be a three-part carbonless manifold form. The ATF is...

49 CFR 40.225 - What form is used for an alcohol test?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 1 2014-10-01 2014-10-01 false What form is used for an alcohol test? 40.225... Testing § 40.225 What form is used for an alcohol test? (a) The DOT Alcohol Testing Form (ATF) must be used for every DOT alcohol test. The ATF must be a three-part carbonless manifold form. The ATF is...

49 CFR 40.225 - What form is used for an alcohol test?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 1 2011-10-01 2011-10-01 false What form is used for an alcohol test? 40.225... Testing § 40.225 What form is used for an alcohol test? (a) The DOT Alcohol Testing Form (ATF) must be used for every DOT alcohol test. The ATF must be a three-part carbonless manifold form. The ATF is...

A Quick Assessment of Visuospatial Abilities in Adolescents Using the Design Organization Test (DOT).

PubMed

Burggraaf, Rudolf; Frens, Maarten A; Hooge, Ignace T C; van der Geest, Jos N

2016-01-01

Tests measuring visuospatial abilities have shown that these abilities increase during adolescence. Unfortunately, the Block Design test and other such tests are complicated and time-consuming to administer, making them unsuitable for use with large groups of restless adolescents. The results of the Design Organization Test (DOT), a quick pen-and-paper test, have been shown to correlate with those of the Block Design test. A group of 198 healthy adolescents (110 male and 88 female) aged 12 to 19 years old participated in this study. A slightly modified version of the DOT has been used in which we shortened the administration time to avoid a ceiling effect in the score. Scores show a linear increase with age (on average 2.0 points per year, r = .61) independent of sex. Scores did not differ between individual setting and group setting. Thus, the DOT is a simple and effective way to assess visuospatial ability in large groups, such as in schools, and it can be easily administered year after year to follow the development of students.

Functional surface engineering of C-dots for fluorescent biosensing and in vivo bioimaging.

PubMed

Ding, Changqin; Zhu, Anwei; Tian, Yang

2014-01-21

Nanoparticles are promising scaffolds for applications such as imaging, chemical sensors and biosensors, diagnostics, drug delivery, catalysis, energy, photonics, medicine, and more. Surface functionalization of nanoparticles introduces an additional dimension in controlling nanoparticle interfacial properties and provides an effective bridge to connect nanoparticles to biological systems. With fascinating photoluminescence properties, carbon dots (C-dots), carbon-containing nanoparticles that are attracting considerable attention as a new type of quantum dot, are becoming both an important class of imaging probes and a versatile platform for engineering multifunctional nanosensors. In order to transfer C-dots from proof-of-concept studies toward real world applications such as in vivo bioimaging and biosensing, careful design and engineering of C-dot probes is becoming increasingly important. A comprehensive knowledge of how C-dot surfaces with various properties behave is essential for engineering C-dots with useful imaging properties such as high quantum yield, stability, and low toxicity, and with desirable biosensing properties such as high selectivity, sensitivity, and accuracy. Several reviews in recent years have reported preparation methods and properties of C-dots and described their application in biosensors, catalysis, photovoltatic cells, and more. However, no one has yet systematically summarized the surface engineering of C-dots, nor the use of C-dots as fluorescent nanosensors or probes for in vivo imaging in cells, tissues, and living organisms. In this Account, we discuss the major design principles and criteria for engineering the surface functionality of C-dots for biological applications. These criteria include brightness, long-term stability, and good biocompatibility. We review recent developments in designing C-dot surfaces with various functionalities for use as nanosensors or as fluorescent probes with fascinating analytical performance, and we emphasize applications in bioimaging and biosensing in live cells, tissues, and animals. In addition, we highlight our work on the design and synthesis of a C-dot ratiometric biosensor for intracellular Cu(2+) detection, and a twophoton fluorescent probe for pH measurement in live cells and tissues. We conclude this Account by outlining future directions in engineering the functional surface of C-dots for a variety of in vivo imaging applications, including dots with combined targeting, imaging and therapeutic-delivery capabilities, or high-resolution multiplexed vascular imaging. With each application C-dots should open new horizons of multiplexed quantitative detection, high-resolution fluorescence imaging, and long-term, real-time monitoring of their target.

Graphene quantum dots for ultrasensitive detection of acetylcholinesterase and its inhibitors

NASA Astrophysics Data System (ADS)

Li, Nan; Wang, Xuewan; Chen, Jie; Sun, Lei; Chen, Peng

2015-09-01

Graphene quantum dots (GQDs) are emerging zero-dimensional materials promising a wide spectrum of novel applications including development of optical sensors. Herein, a GQD-based fluorometric sensor is devised to detect acetylcholinesterase (AChE, a critical enzyme in central nervous system and neuromuscular junctions) with an ultralow detection limit (0.58 pM with S/N of 5.0), using a photoluminescence ‘turn-off’ mechanism. This simple ‘mix-and-detect’ platform can also be employed to sense a variety of compounds that can directly or indirectly inhibit the enzymatic activities of AChE, such as nerve gases, pesticides, and therapeutic drugs. As the proof-of-concept demonstrations, we show the sensitive detection of paraoxon (a pesticide), tacrine (a drug to treat Alzheimer’s disease), and dopamine (an important neurotransmitter).

Fluorescence resonance energy transfer between ZnSe ZnS quantum dots and bovine serum albumin in bioaffinity assays of anticancer drugs

NASA Astrophysics Data System (ADS)

Shu, Chang; Ding, Li; Zhong, Wenying

2014-10-01

In the current work, using ZnSe ZnS quantum dots (QDs) as representative nanoparticles, the affinities of seven anticancer drugs for bovine serum albumin (BSA) were studied using fluorescence resonance energy transfer (FRET). The FRET efficiency of BSA-QD conjugates can reach as high as 24.87% by electrostatic interaction. The higher binding constant (3.63 × 107 L mol-1) and number of binding sites (1.75) between ZnSe ZnS QDs and BSA demonstrated that the QDs could easily associate to plasma proteins and enhance the transport efficacy of drugs. The magnitude of binding constants (103-106 L mol-1), in the presence of QDs, was between drugs-BSA and drugs-QDs in agreement with common affinities of drugs for serum albumins (104-106 L mol-1) in vivo. ZnSe ZnS QDs significantly increased the affinities for BSA of Vorinostat (SAHA), Docetaxel (DOC), Carmustine (BCNU), Doxorubicin (Dox) and 10-Hydroxycamptothecin (HCPT). However, they slightly reduced the affinities of Vincristine (VCR) and Methotrexate (MTX) for BSA. The recent work will not only provide useful information for appropriately understanding the binding affinity and binding mechanism at the molecular level, but also illustrate the ZnSe ZnS QDs are perfect candidates for nanoscal drug delivery system (DDS).

Fixed-dose combination drugs for tuberculosis: application in standardised treatment regimens.

PubMed

Blomberg, Bjørn; Fourie, Bernard

2003-01-01

Short-course chemotherapy is highly efficacious in treating tuberculosis (TB). However, the length (>/=6 months) and complexity (three or four different drugs) of the treatment makes adherence difficult. Erratic treatment not only fails to cure patients but also creates chronically contagious cases, who may excrete drug-resistant TB bacteria. The Directly Observed Treatment Short-course (DOTS) strategy recommended by WHO provides a comprehensive organisational and infrastructural framework for the rational use of diagnosis, drug supply, as well as case and programme management services, in TB control. WHO and other organisations recommend fixed-dose combination formulations (FDCs) as a further step to facilitate the optimal drug treatment of TB. Using FDCs in TB control will simplify the doctor's prescription and patient's drug intake, as well as the drug supply management of the programme. By preventing monotherapy and facilitating the ingestion of adequate doses of the constituent anti-TB drugs, FDCs are expected to help prevent the emergence of drug resistance. This article presents the international recommendations for the use of FDCs in TB programmes. The fundamental issue is to obtain drug supplies of good quality. A laboratory network for quality testing, including bioavailability testing of FDCs exists, and the recently established Global TB Drug Facility (GDF) supplies quality TB drugs, including 4-drug FDCs, to countries requesting assistance. This articles deals with the requirements for a successful transition to FDC-based treatment. It emphasises the need for appropriately revised programme documentation (programme manual, training modules, treatment guidelines and forms), training of staff at all levels, carefully calculated drug needs, and a plan for the exhaustion of existing stocks of loose tablets and the phasing-in of FDCs at all levels of the programme at the same time. Loose drugs for individualised treatment of patients with adverse effects should be kept at district or central health institutions.

49 CFR 107.807 - Approval of non-domestic chemical analyses and tests.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 2 2013-10-01 2013-10-01 false Approval of non-domestic chemical analyses and... Requalifiers, and Non-domestic Chemical Analyses and Tests of DOT Specification Cylinders § 107.807 Approval of non-domestic chemical analyses and tests. (a) General. A person who seeks to manufacture DOT...

MASH test 3-11 of the TxDOT single slope bridge rail (type SSTR) on pan-formed bridge deck

DOT National Transportation Integrated Search

2011-03-01

The objective of this crash test was to determine whether the TxDOT Single Slope Traffic Rail (Type : SSTR) would perform acceptably on a pan-formed deck when tested according to the guidelines set forth in : Manual for Assessing Safety Hardware (MAS...

A Fluorescence Displacement Assay for Antidepressant Drug Discovery Based on Ligand-Conjugated Quantum Dots

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

Chang, Jerry; Tomlinson, Ian; Warnement, Michael

2011-01-01

The serotonin (5-hydroxytryptamine, 5-HT) transporter (SERT) protein plays a central role in terminating 5-HT neurotransmission and is the most important therapeutic target for the treatment of major depression and anxiety disorders. We report an innovative, versatile, and target-selective quantum dot (QD) labeling approach for SERT in single Xenopus oocytes that can be adopted as a drug-screening platform. Our labeling approach employs a custom-made, QD-tagged indoleamine derivative ligand, IDT318, that is structurally similar to 5-HT and accesses the primary binding site with enhanced human SERT selectivity. Incubating QD-labeled oocytes with paroxetine (Paxil), a high-affinity SERT-specific inhibitor, showed a concentration- and time-dependentmore » decrease in QD fluorescence, demonstrating the utility of our approach for the identification of SERT modulators. Furthermore, with the development of ligands aimed at other pharmacologically relevant targets, our approach may potentially form the basis for a multitarget drug discovery platform.« less

Theranostic quantum dots for crossing blood–brain barrier in vitro and providing therapy of HIV-associated encephalopathy

PubMed Central

Xu, Gaixia; Mahajan, Supriya; Roy, Indrajit; Yong, Ken-Tye

2013-01-01

The blood–brain barrier (BBB) is a complex physiological checkpoint that restricts the free diffusion of circulating molecules from the blood into the central nervous system. Delivering of drugs and other active agents across the BBB is one of the major technical challenges faced by scientists and medical practitioners. Therefore, development of novel methodologies to address this challenge holds the key for both the diagnosis and treatment of brain diseases, such as HIV-associated encephalopathy. Bioconjugated quantum dots (QDs) are excellent fluorescent probes and nano-vectors, being designed to transverse across the BBB and visualize drug delivery inside the brain. This paper discusses the use of functionalized QDs for crossing the blood–brain barrier and treating brain disease. We highlight the guidelines for using in vitro BBB models for brain disease studies. The theranostic QDs offers a strategy to significantly improve the effective dosages of drugs to transverse across the BBB and orientate to the targets inside the brain. PMID:24298256

Determinants of Poor Adherence to Anti-Tuberculosis Treatment in Mumbai, India

PubMed Central

Bagchi, Suparna; Ambe, Guirish; Sathiakumar, Nalini

2010-01-01

Objectives: In this study, we investigated the determinants of poor adherence with anti-tuberculosis therapy among pulmonary tuberculosis (TB) patients in Mumbai, India, receiving Directly Observed Treatment Short Course (DOTS) therapy. Methods: A cross-sectional study on 538 patients receiving DOTS I and II regimen was conducted. Patients were interviewed and clinical and laboratory data were collected. Eighty seven patients were considered non-adherent. Multivariable logistic regression was used to determine risk factors associated with non-adherence. Results: Factors associated with non-adherence were found to be different among the newly-diagnosed patients and all the other residual groups. Smoking during treatment and travel-related cost factors were significantly associated with non-adherence in the newly-diagnosed patients, while alcohol consumption and short-age of drugs were significant in the residual groups. Conclusions: An approach, targeting easier access to drugs, an ensured drug supply, effective solutions for travel-related concerns and modification of smoking and alcohol related behaviors are essential for treatment adherence. PMID:21566777

The influence of bio-conjugation on photoluminescence of CdSe/ZnS quantum dots

NASA Astrophysics Data System (ADS)

Torchynska, Tetyana V.; Vorobiev, Yuri V.; Makhniy, Victor P.; Horley, Paul P.

2014-11-01

We report a considerable blue shift in the luminescence spectra of CdSe/ZnS quantum dots conjugated to anti-interleukin-10 antibodies. This phenomenon can be explained theoretically by accounting for bio-conjugation as a process causing electrostatic interaction between a quantum dot and an antibody, which reduces effective volume of the dot core. To solve the Schrödinger equation for an exciton confined in the quantum dot, we use mirror boundary conditions that were successfully tested for different geometries of quantum wells.

MASH test 3-10 on 31-inch w-beam guardrail with standard offset blocks

DOT National Transportation Integrated Search

2011-03-01

The Texas Department of Transportation (TxDOT) initiated a review of their guardrail standards : based on the outcome of recent crash test results and a Federal Highway Administration technical : memorandum pertaining to guardrail height. TxDOT expre...

Dot Projection Photogrammetric Technique for Shape Measurements of Aerospace Test Articles

NASA Technical Reports Server (NTRS)

Jones, Thomas W.; Pappa, Richard S.

2002-01-01

Results from initial laboratory investigations with the dot projection photogrammetric technique are presented for three wind-tunnel test articles with a range of surface scattering and reflection properties. These test articles are a semispan model and a micro air vehicle with a latex wing that are both diffusely reflecting, and a highly polished specularly reflecting model used for high Reynolds number testing. Results using both white light and laser illumination are presented. Some of the advantages and limitations of the dot projection technique are discussed. Although a desirable final outcome of this research effort is the characterization of dynamic behavior, only static laboratory results are presented in this preliminary effort.

USDA analyst review of the LACIE IMAGE-100 hybrid system test

NASA Technical Reports Server (NTRS)

Ashburn, P.; Buelow, K.; Hansen, H. L.; May, G. A. (Principal Investigator)

1979-01-01

Fifty operational segments from the U.S.S.R., 40 test segments from Canada, and 24 test segments from the United States were used to provide a wide range of geographic conditions for USDA analysts during a test to determine the effectiveness of labeling single pixel training fields (dots) using Procedure 1 on the 1-100 hybrid system, and clustering and classifying on the Earth Resources Interactive Processing System. The analysts had additional on-line capabilities such as interactive dot labeling, class or cluster map overlay flickers, and flashing of all dots of equal spectral value. Results on the 1-100 hybrid system are described and analyst problems and recommendations are discussed.

Comparison of aerobic capacity in annually certified and uncertified volunteer firefighters.

PubMed

Hammer, Rodney L; Heath, Edward M

2013-05-01

The leading cause of mortality among firefighters has been cardiac arrest precipitated by stress and overexertion with volunteer firefighters having double the death rate from this cause compared with career firefighters. In an attempt to reduce on-duty sudden cardiac deaths, annual fitness testing, and certification, has been widely instigated in wildland firefighters, who have half the cardiac arrest death rate of structural firefighters. The hypothesis was that annual fitness testing would serve as motivation to produce higher cardiorespiratory fitness. This study compared predicted aerobic capacity in annually certified and uncertified volunteer firefighters. Each firefighter performed a submaximal treadmill test to predict V[Combining Dot Above]O2max. Certified volunteer firefighters, who participated in annual fitness testing, had a predicted V[Combining Dot Above]O2max of 39.9 ± 8.4 ml·kg·min. Uncertified volunteer firefighters had a predicted V[Combining Dot Above]O2max of 37.8 ± 8.5 ml·kg·min. Annual fitness testing during the certification process did not contribute to statistically higher (F2,78 = 0.627, p = 0.431) V[Combining Dot Above]O2max levels in certified volunteer firefighters. Although there was no significant difference in predicted V[Combining Dot Above]O2max values for certified and uncertified volunteer firefighters, it was reported that 30% of volunteer firefighters had predicted aerobic capacities below the recommended minimum V[Combining Dot Above]O2max level of 33.5 ml·kg·min. Current annual fitness testing for volunteer firefighters does not seem to be effective. Thus, the study emphasizes the need of a higher priority for firefighter fitness programs to best ensure the safety of firefighters and the public.

Glutathione modified CdTe quantum dots as a label for studying DNA interactions with platinum based cytostatics.

PubMed

Ryvolova, Marketa; Smerkova, Kristyna; Chomoucka, Jana; Hubalek, Jaromir; Adam, Vojtech; Kizek, Rene

2013-03-01

Cisplatin, carboplatin, and oxaliplatin represent three generations of platinum based drugs applied successfully for cancer treatment. As a consequence of the employment of platinum based cytostatics in the cancer treatment, it became necessary to study the mechanism of their action. Current accepted opinion is the formation of Pt-DNA adducts, but the mechanism of their formation is still unclear. Nanomaterials, as a progressively developing branch, can offer a tool for studying the interactions of these drugs with DNA. In this study, fluorescent CdTe quantum dots (QDs, λem = 525 nm) were employed to investigate the interactions of platinum cytostatics (cisplatin, carboplatin, and oxaliplatin) with DNA fragment (500 bp, c = 25 μg/mL). Primarily, the fluorescent behavior of QDs in the presence of platinum cytostatics was monitored and major differences in the interaction of QDs with tested drugs were observed. It was found that the presence of carboplatin (c = 0.25 mg/mL) had no significant influence on QDs fluorescence; however cisplatin and oxaliplatin quenched the fluorescence significantly (average decrease of 20%) at the same concentration. Subsequently, the amount of platinum incorporated in DNA was determined by QDs fluorescence quenching. Best results were reached using oxaliplatin (9.4% quenching). Linear trend (R(2) = 0.9811) was observed for DNA platinated by three different concentrations of oxaliplatin (0.250, 0.125, and 0.063 mg/mL). Correlation with differential pulse voltammetric measurements provided linear trend (R(2) = 0.9511). As a conclusion, especially in the case of oxaliplatin-DNA adducts, the quenching was the most significant compared to cisplatin and nonquenching carboplatin. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A sulphonated carbon dot-chitosan hybrid hydrogel nanocomposite as an efficient ion-exchange film for Ca2+ and Mg2+ removal

NASA Astrophysics Data System (ADS)

Baruah, Upama; Konwar, Achyut; Chowdhury, Devasish

2016-04-01

We have developed a hybrid hydrogel nanocomposite film via conjugation of oxidised carbon dots synthesized from 11-mercaptoundecanoic acid with chitosan. The potential applicability of the film was then successfully tested for the removal of Ca2+ and Mg2+ ions from solution.We have developed a hybrid hydrogel nanocomposite film via conjugation of oxidised carbon dots synthesized from 11-mercaptoundecanoic acid with chitosan. The potential applicability of the film was then successfully tested for the removal of Ca2+ and Mg2+ ions from solution. Electronic supplementary information (ESI) available: The ESI includes the detailed synthesis and characterization of carbon dots both before and after oxidation and of the carbon dot-chitosan nanocomposite films viz. DLS, SEM, UV-visible, FTIR, PL spectroscopy and TGA. See DOI: 10.1039/c6nr01129b

Side impact test and analyses of a DOT-111 tank car : final report.

DOT National Transportation Integrated Search

2015-10-01

Transportation Technology Center, Inc. conducted a side impact test on a DOT-111 tank car to evaluate the performance of the : tank car under dynamic impact conditions and to provide data for the verification and refinement of a computational model. ...

Integrated vehicle-based safety systems : heavy-truck field operational test independent evaluation.

DOT National Transportation Integrated Search

2011-05-01

This report presents results from the independent evaluation of a field operational test using a fleet of heavy trucks outfitted with a prototype integrated crash warning system. This effort was conducted as part of the U.S. DOT?s Integrated Vehicle-...

A simple turn on fluorescent sensor for the selective detection of thiamine using coconut water derived luminescent carbon dots.

PubMed

Purbia, Rahul; Paria, Santanu

2016-05-15

In this study microwave-assisted hydrothermal method was used to prepare highly luminescent carbon dots (1-6 nm size) within a minute from tender coconut (Cocos nucifera) water. The synthesized carbon dots (C-dots) exhibit emission of blue and green lights while excited at 390 and 450 nm wavelengths, respectively. As an application, these C-dots were tested for a simple "turn on" fluorescent sensor for rapid detection of thiamine (vitamin B1). The detection of thiamine in human body is very important to prevent various diseases such as beriberi, neurological disorders, optic neuropathy, etc. The fluorescence emission intensity of C-dots quenches after addition of Cu(2+) ion and then again increases selectively (turn on) after the addition of thiamine. The fluorescence emission intensity enhancement of Cu(2+) ion modified C-dots in the presence of thiamine exhibits a linear relationship within the thiamine concentration range of 10-50 μM. The limit of detection was found to be 280 nM from this study. The selectivity of the detection was also tested in the presence of different organic molecules and inorganic ions (Ca(2+), Mg(2+), Na(+), K(+), Cl(-), SO4(2-), and NO3(-)) which are present in blood serum and urine and found to be almost no interference in the detection. Finally, to see the applicability in real samples a commercial vitamin capsule was tested and found less than 3% error in the detected concentration. The C-dots were also used for bioimaging of fungus and the results show they are also suitable for this application too. Copyright © 2015 Elsevier B.V. All rights reserved.

Synthesis of upconversion nanoparticles conjugated with graphene oxide quantum dots and their use against cancer cell imaging and photodynamic therapy.

PubMed

Choi, Seung Yoo; Baek, Seung Hoon; Chang, Sung-Jin; Song, Yohan; Rafique, Rafia; Lee, Kang Taek; Park, Tae Jung

2017-07-15

Multifunctional nanocomposite has a huge potential for cell imaging, drug delivery, and improving therapeutic effect with less side effects. To date, diverse approaches have been demonstrated to endow a single nanostructure with multifunctionality. Herein, we report the synthesis and application of core-shell nanoparticles composed with upconversion nanoparticle (UCNP) as a core and a graphene oxide quantum dot (GOQD) as a shell. The UCNP was prepared and applied for imaging-guided analyses of upconversion luminescence. GOQD was prepared and employed as promising drug delivery vehicles to improve anti-tumor therapy effect in this study. Unique properties of UCNPs and GOQDs were incorporated into a single nanostructure to provide desirable functions for cell imaging and drug delivery. In addition, hypocrellin A (HA) was loaded on GOQDs for photo-dynamic therapy (PDT). HA, a commonly used chemotherapy drug and a photo-sensitizer, was conjugated with GOQD by π-π interaction and loaded on PEGylated UCNP without complicated synthetic process, which can break structure of HA. Applying these core-shell nanoparticles to MTT assay, we demonstrated that the UCNPs with GOQD shell loaded with HA could be excellent candidates as multifunctional agents for cell imaging, drug delivery and cell therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

Multifunctional inulin tethered silver-graphene quantum dots nanotheranostic module for pancreatic cancer therapy.

PubMed

Nigam Joshi, Preeti; Agawane, Sachin; Athalye, Meghana C; Jadhav, Vrushali; Sarkar, Dhiman; Prakash, Rajiv

2017-09-01

Cancer nanotechnology is an emerging area of cancer diagnosis and therapy. Although considerable progress has been made for targeted drug delivery systems to deliver anticancer agents to particular site of interest, new nanomaterials are frequently being developed and explored for better drug delivery efficiency. In the present work, we have explored a novel nanoformulation based on silver-graphene quantum dots (Ag-GQDs) nanocomposite for its successful implementation for pancreatic cancer specific drug delivery in wistar rats. Carboxymethyl inulin (CMI); a modified variant of natural polysaccharide inulin is tethered with the nanocomposite via carbodiimide coupling to enhance the biocompatibility of nanoformulation. Experiments are performed to investigate the cytotoxicity reduction of silver nanoparticles after inulin tethering as well as anticancer efficacy of the system using 5-Fluorouracil (5-FU) as model drug. SEM, TEM, FT-IR, UV-vis, photoluminescence and anti proliferative assays (MTT) are performed for characterisation of the nanocomposite. Hyaluronic acid (HA) is conjugated as targeting moiety for CD-44 (cancer stem cell marker) to fabricate a complete targeted drug delivery vehicle specific for pancreatic cancer. In the present work two prime objectives were achieved; mitigation the toxicity of silver nanoparticles by inulin coating and it's in vivo application for pancreatic cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

Improving lab compaction specifications for flexible bases within the Texas DOT.

DOT National Transportation Integrated Search

2009-04-01

In Test Methods Tex-113-E and Tex-114-E, the Texas Department of Transportation (TxDOT) employs an impact hammer method of sample compaction for laboratory preparation of road base and subgrade materials for testing. In this third and final report do...

MASH test 3-11 of the TxDOT T222 bridge rail.

DOT National Transportation Integrated Search

2016-07-01

The objective of this research was to evaluate the impact performance of the TxDOT Type T222 : Bridge Rail according to the Manual for Assessing Safety Hardware (MASH) TL-3. The crash testing was : performed in accordance with the requirements of MAS...

MASH test 3-21 on TL-3 thrie beam transition without curb.

DOT National Transportation Integrated Search

2013-01-01

This project evaluated the impact performance of a modified TxDOT thrie beam transition to rigid : concrete barrier without a curb element below the transition rail. In a previous test described in TxDOT : Research Report 0-4564, a thrie beam transit...

Superoxide scavenging activity of pirfenidone-iron complex

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

Mitani, Yoshihiro; Sato, Keizo; Muramoto, Yosuke

Pirfenidone (PFD) is focused on a new anti-fibrotic drug, which can minimize lung fibrosis etc. We evaluated the superoxide (O{sub 2}{sup {center_dot}}{sup -}) scavenging activities of PFD and the PFD-iron complex by electron spin resonance (ESR) spectroscopy, luminol-dependent chemiluminescence assay, and cytochrome c reduction assay. Firstly, we confirmed that the PFD-iron complex was formed by mixing iron chloride with threefold molar PFD, and the complex was stable in distillated water and ethanol. Secondary, the PFD-iron complex reduced the amount of O{sub 2}{sup {center_dot}}{sup -} produced by xanthine oxidase/hypoxanthine without inhibiting the enzyme activity. Thirdly, it also reduced the amount ofmore » O{sub 2}{sup {center_dot}}{sup -} released from phorbor ester-stimulated human neutrophils. PFD alone showed few such effects. These results suggest the possibility that the O{sub 2}{sup {center_dot}}{sup -} scavenging effect of the PFD-iron complex contributes to the anti-fibrotic action of PFD used for treating idiopathic pulmonary fibrosis.« less

A molecularly imprinted dual-emission carbon dot-quantum dot mesoporous hybrid for ratiometric determination of anti-inflammatory drug celecoxib

NASA Astrophysics Data System (ADS)

Amjadi, Mohammad; Jalili, Roghayeh

2018-02-01

We report on a ratiometric fluorescent sensor based on dual-emission molecularly imprinted mesoporous silica embedded with carbon dots and CdTe quantum dots (mMIP@CDs/QDs) for celecoxib (CLX) as target molecule. The fluorescence of the embedded CDs is insensitive to the analyte while the green emissive QDs are selectively quenched by it. This effect is much stronger for the MIP than for the non-imprinted polymer, which indicates a good recognition ability of the mesoporous MIP. The hybrid sensor also exhibited good selectivity to CLX over other substances. The ratio of the intensity at two wavelengths (F550/F440) proportionally decreased with the increasing of CLX concentration in the range of 0.08-0.90 μM. A detection limit as low as 57 nM was achieved. Experimental results testified that this sensor was highly sensitive and selective for the detection of CLX in human serum samples.

In-situ immobilization of quantum dots in polysaccharide-based nanogels for integration of optical pH-sensing, tumor cell imaging, and drug delivery.

PubMed

Wu, Weitai; Aiello, Michael; Zhou, Ting; Berliner, Alexandra; Banerjee, Probal; Zhou, Shuiqin

2010-04-01

We report a class of polysaccharide-based hybrid nanogels that can integrate the functional building blocks for optical pH-sensing, cancer cell imaging, and controlled drug release into a single nanoparticle system, which can offer broad opportunities for combined diagnosis and therapy. The hybrid nanogels were prepared by in-situ immobilization of CdSe quantum dots (QDs) in the interior of the pH and temperature dual responsive hydroxypropylcellulose-poly(acrylic acid) (HPC-PAA) semi-interpenetrating polymer networks. The-OH groups of the HPC chains are designed to sequester the precursor Cd(2+) ions into the nanogels as well as stabilize the in-situ formed CdSe QDs. The pH-sensitive PAA network chains are designed to induce a pH-responsive volume phase transition of the hybrid nanogels. The developed HPC-PAA-CdSe hybrid nanogels combine a strong trap emission at 741nm for sensing physicochemical environment in a pH dependent manner and a visible excitonic emission at 592nm for mouse melanoma B16F10 cell imaging. The hybrid nanogels also provide excellent stability as a drug carrier, which cannot only provide a high drug loading capacity for a model anticancer drug temozolomide, but also offer a pH-triggered sustained-release of the drug molecules in the gel network. Copyright 2010 Elsevier Ltd. All rights reserved.

Cost of Behavioral Interventions Utilizing Electronic Drug Monitoring for Antiretroviral Therapy Adherence

PubMed Central

Rasu, Rafia S.; Malewski, David F.; Banderas, Julie W.; Thomson, Domonique Malomo; Goggin, Kathy

2013-01-01

Objective To provide data on the actual costs associated with behavioral ART adherence interventions and electronic drug monitoring used in a clinical trial to inform their implementation in future studies and real-world practice. Methods Direct and time costs were calculated from a multi-site three-arm randomized controlled ART adherence trial. HIV positive participants (n = 204) were randomized to standard care (SC), enhanced counseling (EC), or EC and modified directly observed therapy (mDOT) interventions. Electronic drug monitoring (EDM) was used. Costs were calculated for various components of the 24-week adherence intervention. This economic evaluation was conducted from the perspective of an agency that may wish to implement these strategies. Sensitivity analyses were conducted to examine costs and savings associated with different scenarios. Results Total direct costs were $126,068 ($618/patient). Initial time costs were $53,590 ($262/patient). Base cost of labor was $0.36/minute. EC costs for 134 patients were $18,427 ($137/patient) and mDOT for 64 patients cost $18,638 ($291/patient). Total per patient costs were: SC=$880, EC=$1,018, EC/mDOT=$1,309. Removing driving costs evidenced the most variable impact on savings between the three study arms. The tornado diagram (sensitivity analysis) showed a graphical representation of how each sensitivity assumption reduced costs compared to each other and the resulting comparative costs for each group. Conclusion This novel economic analysis provides valuable cost information to guide treatment implementation and research design decisions. PMID:23337364

Multifunctional superparamagnetic nanoparticles for enhanced drug transport in cystic fibrosis

NASA Astrophysics Data System (ADS)

Armijo, Leisha M.; Brandt, Yekaterina I.; Rivera, Antonio C.; Cook, Nathaniel C.; Plumley, John B.; Withers, Nathan J.; Kopciuch, Michael; Smolyakov, Gennady A.; Huber, Dale L.; Smyth, Hugh D.; Osinski, Marek

2012-10-01

Iron oxide colloidal nanoparticles (ferrofluids) are investigated for application in the treatment of cystic fibrosis lung infections, the leading cause of mortality in cystic fibrosis patients. We investigate the use of iron oxide nanoparticles to increase the effectiveness of administering antibiotics through aerosol inhalation using two mechanisms: directed particle movement in the presence of an inhomogeneous static external magnetic field and magnetic hyperthermia. Magnetic hyperthermia is an effective method for decreasing the viscosity of the mucus and biofilm, thereby enhancing drug, immune cell, and antibody penetration to the affected area. Iron oxide nanoparticles of various sizes and morphologies were synthesized and tested for specific losses (heating power). Nanoparticles in the superparamagnetic to ferromagnetic size range exhibited excellent heating power. Additionally, iron oxide / zinc selenide core/shell nanoparticles were prepared, in order to enable imaging of the iron oxide nanoparticles. We also report on synthesis and characterization of MnSe/ZnSeS alloyed quantum dots.

Anticancer drug-DNA interactions measured using a photoinduced electron-transfer mechanism based on luminescent quantum dots.

PubMed

Yuan, Jipei; Guo, Weiwei; Yang, Xiurong; Wang, Erkang

2009-01-01

A sensing system based on the photoinduced electron transfer of quantum dots (QDs) was designed to measure the interaction of anticancer drug and DNA, taking mitoxantrone (MTX) as a model drug. MTX adsorbed on the surface of QDs can quench the photoluminescence (PL) of QDs through the photoinduced electron-transfer process; and then the addition of DNA will bring the restoration of QDs PL intensity, as DNA can bind with MTX and remove it from QDs. Sensitive detection of MTX with the detection limit of 10 nmol L(-1) and a linear detection range from 10 nmol L(-1) to 4.5 micromol L(-1) was achieved. The dependence of PL intensity on DNA amount was successfully utilized to investigate the interactions between MTX and DNA. Both the binding constants and the sizes of binding site of MTX-DNA interactions were calculated based on the equations deduced for the PL recovery process. The binding constant obtained in our experiment was generally consistent with previous reports. The sensitive and speedy detection of MTX as well as the avoidance of modification or immobilization process made this system suitable and promising in the drug-DNA interaction studies.

49 CFR 40.261 - What is a refusal to take an alcohol test, and what are the consequences?

Code of Federal Regulations, 2010 CFR

2010-10-01

... what are the consequences? 40.261 Section 40.261 Transportation Office of the Secretary of... Testing § 40.261 What is a refusal to take an alcohol test, and what are the consequences? (a) As an... incur the same consequences specified under DOT agency regulations for a violation of those DOT agency...

ORANGES evaluation test plans : analysis of before data collected for the US DOT sponsored evaluation of the ORANGES electronic payment systems field operational test

DOT National Transportation Integrated Search

2003-10-02

This document is one of a series of working papers that report on progress for the US DOT evaluation for Phase I of the ORANGES field operational test. Each working paper corresponds to a Phase I task. At the conclusion of Phase I, these documents wi...

ORANGES evaluation final report appendices : for the US DOT sponsored evaluation of the ORANGES electronic payment systems field operational test

DOT National Transportation Integrated Search

2004-12-06

These are the appendices for the report describing the findings of the US DOT-sponsored evaluation of the Orlando (Florida) ORANGES multi-modal Field Operational Test (FOT); the report includes: a background description of the ORANGES FOT; the Evalua...

ORANGES evaluation final report : for the US DOT sponsored evaluation of the ORANGES electronic payment systems field operational test

DOT National Transportation Integrated Search

2004-12-06

This report describes the findings of the US DOT-sponsored evaluation of the Orlando (Florida) ORANGES multi-modal Field Operational Test (FOT); the report includes: a background description of the ORANGES FOT; the Evaluation Strategy and Plan, which...

Statement of Work for Volpe Center Execution of DOT GPS Adjacent Band Compatibility Testing Program

DOT National Transportation Integrated Search

2015-01-01

DOT should cause GPS firms to produce to Volpe for testing the following devices: The ten (10) top selling device models in the United States for the calendar year 2014. In addition GPS manufacturers will provide Volpe with the identities of their to...

The identification of high-affinity G protein-coupled receptor ligands from large combinatorial libraries using multicolor quantum dot-labeled cell-based screening

PubMed Central

Fu, Junjie; Lee, Timothy; Qi, Xin

2014-01-01

G protein-coupled receptors (GPCRs), which are involved in virtually every biological process, constitute the largest family of transmembrane receptors. Many top-selling and newly approved drugs target GPCRs. In this review, we aim to recapitulate efforts and progress in combinatorial library-assisted GPCR ligand discovery, particularly focusing on one-bead-one-compound library synthesis and quantum dot-labeled cell-based assays, which both effectively enhance the rapid identification of GPCR ligands with higher affinity and specificity. PMID:24941874

Mars 2024/2026 Pathfinder Mission: Mars Architectures, Systems, and Technologies for Exploration and Resources Project

NASA Technical Reports Server (NTRS)

Zeitlin, Nancy; Mueller, Robert; Muscatello, Anthony

2015-01-01

Integrate In Situ Resource Utilization (ISRU) sub-systems and examine advanced capabilities and technologies to verify Mars 2024 Forward architecture precursor pathfinder options: Integrated spacecraft/surface infrastructure fluid architecture: propulsion, power, life support center dot Power system feed and propellant scavenging from propulsion system center dot High quality oxygen for life support and EVA Fluid/cryogenic zero-loss transfer and long-term storage center dot Rapid depot-to-rover/spacecraft center dot Slow ISRU plant-to-ascent vehicle Integration of ISRU consumable production center dot Oxygen only from Mars atmosphere carbon dioxide center dot Oxygen, fuel, water, from extraterrestrial soil/regolith Test bed to evaluate long duration life, operations, maintenance on hardware, sensors, and autonomy

Functionality of bismuth sulfide quantum dots/wires-glass nanocomposite as an optical current sensor with enhanced Verdet constant

NASA Astrophysics Data System (ADS)

Panmand, Rajendra P.; Kumar, Ganapathy; Mahajan, Satish M.; Kulkarni, Milind V.; Amalnerkar, D. P.; Kale, Bharat B.; Gosavi, Suresh. W.

2011-02-01

We report optical studies with magneto-optic properties of Bi2S3 quantum dot/wires-glass nanocomposite. The size of the Q-dot was observed to be in the range 3-15 nm along with 11 nm Q-wires. Optical study clearly demonstrated the size quantization effect with drastic band gap variation with size. Faraday rotation tests on the glass nanocomposites show variation in Verdet constant with Q-dot size. Bi2S3 Q-dot/wires glass nanocomposite demonstrated 190 times enhanced Verdet constant compared to the host glass. Prima facie observations exemplify the significant enhancement in Verdet constant of Q-dot glass nanocomposites and will have potential application in magneto-optical devices.

Associations between national tuberculosis program budgets and tuberculosis outcomes: an ecological study.

PubMed

Chapple, Will; Katz, Alan Roy; Li, Dongmei

2012-01-01

The objective of this study is to explore the associations between national tuberculosis program (NTP) budget allocation and tuberculosis related outcomes in the World Health Organization's 22 high burden countries from 2007-2009. This ecological study used mixed effects and generalized estimating equation models to identify independent associations between NTP budget allocations and various tuberculosis related outcomes. Models were adjusted for a number of independent variables previously noted to be associated with tuberculosis incidence. Increasing the percent of the NTP budget for advocacy, communication and social mobilization was associated with an increase in the case detection rate. Increasing TB-HIV funding was associated with an increase in HIV testing among TB patients. Increasing the percent of the population covered by the Directly Observed Therapy (DOT) program was associated with an increase in drug susceptibility testing. Laboratory funding was positively associated with tuberculosis notification. Increasing the budgets for first line drugs, management and multi-drug resistant tuberculosis (MDR-TB) was associated with a decrease in smear positive deaths. Effective TB control is a complex and multifaceted challenge. This study revealed a number of budget allocation related factors associated with improved TB outcome parameters. If confirmed with future longitudinal studies, these findings could help guide NTP managers with allocation decisions.

Associations between national tuberculosis program budgets and tuberculosis outcomes: an ecological study

PubMed Central

Chapple, Will; Katz, Alan Roy; Li, Dongmei

2012-01-01

Introduction The objective of this study is to explore the associations between national tuberculosis program (NTP) budget allocation and tuberculosis related outcomes in the World Health Organization's 22 high burden countries from 2007–2009. Methods This ecological study used mixed effects and generalized estimating equation models to identify independent associations between NTP budget allocations and various tuberculosis related outcomes. Models were adjusted for a number of independent variables previously noted to be associated with tuberculosis incidence. Results Increasing the percent of the NTP budget for advocacy, communication and social mobilization was associated with an increase in the case detection rate. Increasing TB-HIV funding was associated with an increase in HIV testing among TB patients. Increasing the percent of the population covered by the Directly Observed Therapy (DOT) program was associated with an increase in drug susceptibility testing. Laboratory funding was positively associated with tuberculosis notification. Increasing the budgets for first line drugs, management and multi-drug resistant tuberculosis (MDR-TB) was associated with a decrease in smear positive deaths. Conclusion Effective TB control is a complex and multifaceted challenge. This study revealed a number of budget allocation related factors associated with improved TB outcome parameters. If confirmed with future longitudinal studies, these findings could help guide NTP managers with allocation decisions. PMID:23024825

Development of a rapid diagnostic test for pertussis: direct detection of pertussis toxin in respiratory secretions.

PubMed Central

Friedman, R L; Paulaitis, S; McMillan, J W

1989-01-01

Monoclonal antibodies (MAb) were produced against the specific Bordetella pertussis antigen pertussis toxin (PT). In preliminary studies, one MAb (IB12) was selected and used in an enzyme-linked dot blot immunoassay to evaluate the ability of the method to detect known amounts of PT in control experiments and to test its potential for direct detection of PT in nasopharyngeal secretion (NP) specimens from patients with confirmed cases of whooping cough. The dot blot assay was able to detect PT at levels as low as 10 ng per dot in either buffer or control NP specimens. The assay demonstrated specificity, reacting only with dot blots of whole B. pertussis and not Bordetella bronchiseptica, Bordetella parapertussis, or other bacterial strains. In preliminary studies, NP aspirate, swab, and wash specimens were compared. The specimen of choice was found to be the NP aspirate, for which 100% positive results were found in the assay. These initial studies suggest that the dot blot immunoassay in which a MAb is used for direct detection of PT in NP specimens may be useful as a rapid diagnostic test for pertussis. Images PMID:2808670

Fluorophotometric determination of critical micelle concentration (CMC) of ionic and non-ionic surfactants with carbon dots via Stokes shift.

PubMed

Lavkush Bhaisare, Mukesh; Pandey, Sunil; Shahnawaz Khan, M; Talib, Abou; Wu, Hui-Fen

2015-01-01

A new and facile method for the determination of critical micelle concentration (CMC) of ionic and non-ionic surfactants is proposed in this article. Carbon dots exhibited substantial fluorescence and therefore enhanced the sensitivity of this evaluation. Understanding the formation of surfactant micelles is vital for the applications of biomedicine such as drug fabrication and smart molecular vehicles in delivering therapeutic dosage to various molecular sites. The fluorescence property of carbon dots was utilized for the first time to estimate the critical micelle concentration of surfactants. The central concept of the approach is based on the Stokes shift determination of a system composed of constant amount of carbon dots with varying concentrations of ionic and non-ionic surfactants. The synthesized carbon dots were characterized by FTIR, TEM, XRD, Raman, UV, and fluorescence spectroscope. The carbon dots were excited at 280 nm so as to obtain maximum emission for the Stokes shift measurement. The CMC value of cetyltrimethyl ammonium bromide (CTAB), sodium dodecyl sulfate (SDS), Triton X-100, dodecyldimethyl(3-sulfopropyl)ammonium hydroxide (SB-12) evaluated by this approach was found to be 0.98, 7.3, 0.19, and 3.5mM, respectively. The signals of spectra were assigned and explained in terms of both electron transitions between specific molecular orbital and the interaction with solvent. Copyright © 2014 Elsevier B.V. All rights reserved.

Magnetic/NIR-thermally responsive hybrid nanogels for optical temperature sensing, tumor cell imaging and triggered drug release

NASA Astrophysics Data System (ADS)

Wang, Hui; Yi, Jinhui; Mukherjee, Sumit; Banerjee, Probal; Zhou, Shuiqin

2014-10-01

The paper demonstrates a class of multifunctional core-shell hybrid nanogels with fluorescent and magnetic properties, which have been successfully developed for simultaneous optical temperature sensing, tumor cell imaging and magnetic/NIR-thermally responsive drug carriers. The as-synthesized hybrid nanogels were designed by coating bifunctional nanoparticles (BFNPs, fluorescent carbon dots embedded in the porous carbon shell and superparamagnetic iron oxide nanocrystals clustered in the core) with a thermo-responsive poly(N-isopropylacrylamide-co-acrylamide) [poly(NIPAM-AAm)]-based hydrogel as the shell. The BFNPs in hybrid nanogels not only demonstrate excellent photoluminescence (PL) and photostability due to the fluorescent carbon dots embedded in the porous carbon shell, but also has targeted drug accumulation potential and a magnetic-thermal conversion ability due to the superparamagnetic iron oxide nanocrystals clustered in the core. The thermo-responsive poly(NIPAM-AAm)-based gel shell can not only modify the physicochemical environment of the BFNPs core to manipulate the fluorescence intensity for sensing the variation of the environmental temperature, but also regulate the release rate of the loaded anticancer drug (curcumin) by varying the local temperature of environmental media. In addition, the carbon layer of BFNPs can adsorb and convert the NIR light to heat, leading to a promoted drug release under NIR irradiation and improving the therapeutic efficacy of drug-loaded hybrid nanogels. Furthermore, the superparamagnetic iron oxide nanocrystals in the core of BFNPs can trigger localized heating using an alternating magnetic field, leading to a phase change in the polymer gel to trigger the release of loaded drugs. Finally, the multifunctional hybrid nanogels can overcome cellular barriers to enter the intracellular region and light up the mouse melanoma B16F10 cells. The demonstrated hybrid nanogels would be an ideal system for the biomedical applications due to their excellent optical properties, magnetic properties, high drug loading capacity and responsive drug release behavior.The paper demonstrates a class of multifunctional core-shell hybrid nanogels with fluorescent and magnetic properties, which have been successfully developed for simultaneous optical temperature sensing, tumor cell imaging and magnetic/NIR-thermally responsive drug carriers. The as-synthesized hybrid nanogels were designed by coating bifunctional nanoparticles (BFNPs, fluorescent carbon dots embedded in the porous carbon shell and superparamagnetic iron oxide nanocrystals clustered in the core) with a thermo-responsive poly(N-isopropylacrylamide-co-acrylamide) [poly(NIPAM-AAm)]-based hydrogel as the shell. The BFNPs in hybrid nanogels not only demonstrate excellent photoluminescence (PL) and photostability due to the fluorescent carbon dots embedded in the porous carbon shell, but also has targeted drug accumulation potential and a magnetic-thermal conversion ability due to the superparamagnetic iron oxide nanocrystals clustered in the core. The thermo-responsive poly(NIPAM-AAm)-based gel shell can not only modify the physicochemical environment of the BFNPs core to manipulate the fluorescence intensity for sensing the variation of the environmental temperature, but also regulate the release rate of the loaded anticancer drug (curcumin) by varying the local temperature of environmental media. In addition, the carbon layer of BFNPs can adsorb and convert the NIR light to heat, leading to a promoted drug release under NIR irradiation and improving the therapeutic efficacy of drug-loaded hybrid nanogels. Furthermore, the superparamagnetic iron oxide nanocrystals in the core of BFNPs can trigger localized heating using an alternating magnetic field, leading to a phase change in the polymer gel to trigger the release of loaded drugs. Finally, the multifunctional hybrid nanogels can overcome cellular barriers to enter the intracellular region and light up the mouse melanoma B16F10 cells. The demonstrated hybrid nanogels would be an ideal system for the biomedical applications due to their excellent optical properties, magnetic properties, high drug loading capacity and responsive drug release behavior. Electronic supplementary information (ESI) available: Fig. S1-S12. See DOI: 10.1039/c4nr03748k

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.

Contribution of dot-blot assay to the diagnosis and management of myositis: a three-year practice at a university hospital centre.

PubMed

Martel, Clothilde; Vignaud, Guillaume; Liozon, Eric; Magy, Laurent; Gallouedec, Gael; Ly, Kim; Bezanahary, Holly; Cypierre, Anne; Lapébie, François-Xavier; Palat, Sylvain; Gondran, Guillaume; Jauberteau, Marie-Odile; Fauchais, Anne-Laure

2016-01-01

Idiopathic inflammatory myopathies (IIM) are heterogeneous autoimmune diseases with wide clinical spectrum that may lead to delayed diagnosis. The aim of this study was to examine the impact of IIM-specific dot-blot assay on diagnostic process of patients presenting with muscular or systemic symptoms evocating of IIM. We collected all the prescriptions of an IIM specific dot-blot assay (8 autoantigens including Jo-1, PL-7, PL-12, SRP, Mi-2, Ku, PM/Scl and Scl-70) over a 38-month period. 316 myositis dot-blot assays (MSD) were performed in 274 patients (156 women, mean age 53±10.6 years) referring for muscular and/or systemic symptoms suggesting IIM. The timing of dot prescription through the diagnostic process was highly variable: without (35%), concomitantly (16%) or after electromyographic studies (35%). Fifty-nine patients (22%) had IIM according to Bohan and Peter's criteria. Among them, 29 (49%) had positive dot (8 Jo-1, 6 PM-Scl, 5 PL-12, 5 SRP, 2 Mi-2, 2 PL-7 and 1 Ku). Various other diagnoses were performed including 35 autoimmune disease or granulomatosis (12%), 19 inflammatory rheumatic disease (7%), 16 non inflammatory muscular disorders (6%), 10 drug-induced myalgia (4%), 11 infectious myositis (4%). Except 11 borderline SRP results and one transient PM-Scl, MSD was positive only in one case of IIM. Dot allowed clinicians to correct diagnosis in 4 cases and improved the diagnosis of IIM subtypes in 4 cases. This study reflects the interest of myositis dot in the rapid diagnosis process of patients with non-specific muscular symptoms leading to various diagnoses including IIM.

Toward the in vivo study of captopril-conjugated quantum dots

NASA Astrophysics Data System (ADS)

Manabe, Noriyoshi; Hoshino, Akiyoshi; Liang, Yi-qiang; Goto, Tomomasa; Kato, Norihiro; Yamamoto, Kenji

2005-04-01

Photo-luminescent semiconductor quantum dots are nanometer-size probes that have the potential to be applied to the fields of the bio-imaging and the study of the cell mobility inside the body. At the same time, on the other hand, quantum dots are expected to carry some kind of molecules to the local organ inside of the animal body, which leads to the expectation that they can be used as a medicine-carrier. For this purpose, we conjugate (2S)-1-[(2s)-2-Methyl-3-sulfanylpropionyl]pyrrolidine-2-carboxylic acid (cap) with the quantum dot. Cap has the effect as an anti-hypertension drug, which inhibits angiotensin 1 converting enzyme. We conjugated the quantum dot with cap by the exchange reaction avoiding the regions which holds medicinal effect. Quantum dot conjugated with cap (QD-cap) were 3-times brighter than thioglycerol-coated quantum dots (QD-OH). The particle size of cap was 1.1nm and that of QD-cap was 12nm. QD-cap was permeated into the HeLa cells, while QD-MUA were taken into the HeLa cells by endocytosis. In addition, no apoptosis was detected against the cells that permeated QD-cap, because there was no damage to DNA. These results indicated that QD-conjugated medicines (QD-medicine) could be safe in the experiment on the level of the cell. More over, when QD-cap was intravenously injected into Stroke-prone Spontaneously Hypertensive Rats (SHRSP), they reduced blood pressure at systole. Therefore, the anti-hypertension effect of cap remained after conjugated with the quantum dot. These results suggested that QD-medicine were effective on the animal level.

X-ray Crystal Structures of the Type IVb Secretion System DotB ATPases.

PubMed

Prevost, Marie S; Waksman, Gabriel

2018-05-17

Human infections by the intracellular bacterial pathogen Legionella pneumophila result in a severe form of pneumonia, the Legionnaire's disease. L. pneumophila utilises a type IVb secretion (T4bS) system termed "dot/icm" to secrete protein effectors to the host cytoplasm. The dot/icm system is powered at least in part by a functionally critical AAA+ ATPase, a protein called DotB, thought to belong to the VirB11 family of proteins. Here we present the crystal structure of DotB at 3.19 Å resolution, in its hexameric form. We observe that DotB is in fact a structural intermediate between VirB11 and PilT family proteins, with a PAS-like N-terminal domain coupled to a RecA-like C-terminal domain. It also shares critical structural elements only found in PilT. The structure also reveals two conformers, termed α and β, with an αβαβαβ configuration. The existence of α and β conformers in this class of proteins was confirmed by solving the structure of DotB from another bacterial pathogen, Yersinia, where, intriguingly, we observed an ααβααβ configuration. The two conformers co-exist regardless of the nucleotide-bound states of the proteins. Our investigation therefore reveals that these ATPases can adopt a wider range of conformational states than was known before, shedding new light on the extraordinary spectrum of conformations these ATPases can access to carry out their function. Overall, the structure of DotB provides a template for further rational drug-design to develop more specific antibiotics to tackle Legionnaire's disease. This article is protected by copyright. All rights reserved. © 2018 The Protein Society.

Interpretation of echo sounding and sub-bottom profiling data : Mark Twain Bridge A-3798, MoDOT Route 107

DOT National Transportation Integrated Search

2008-02-01

The project consists of essentially doing what is outlined in the objective above. In addition, MoDOT will be responsible for choosing the 30 soils and 5 base materials to be tested, for doing initial property tests on them, and delivering them to UM...

Examining the Return on Investment of Test and Evaluation

DTIC Science & Technology

2015-03-26

Problem Discovery Cases Observed in DOT&E Oversight Programs ............... 4 Figure 2. DoD T&E Organizational Structure...11 Figure 3. Product Maturity Levels Commercial Firms Seek to Validate ........................ 23 Figure 4 ...beginning in its fiscal year (FY) 2011 report, the Director, Operational Test and Evaluation (DOT&E), started reporting significant issues observed

ORANGES evaluation phase I risk assessment report : phase I of the US DOT sponsored evaluation of the ORANGES electronic payment system field operational test

DOT National Transportation Integrated Search

2004-03-11

This document is the US DOT evaluation Risk Assessment report for Phase I of the ORANGES field operational test. This document consolidates working papers and incorporates an assessment of issues, risks, mitigation strategies and lessons learned look...

Selection of a Clostridium perfringens type D epsilon toxin producer via dot-blot test.

PubMed

Gonçalves, Luciana A; Lobato, Zélia I P; Silva, Rodrigo O S; Salvarani, Felipe M; Pires, Prhiscylla S; Assis, Ronnie A; Lobato, Francisco C F

2009-11-01

Clostridium perfringens type D produces enterotoxemia, an enteric disease in ruminants, also known as pulpy kidney disease. Caused by epsilon toxin, enterotoxemia is a major exotoxin produced by this microorganism. Epsilon toxin is also the main component of vaccines against this enteric disorder. In this study, a standardized dot-blot was used to choose strains of C. perfringens type D that are producers of epsilon toxin. Clones producing epsilon toxin were chosen by limiting dilution; after three passages, lethal minimum dose titers were determined by soroneutralization test in mice. These clones produced epsilon toxin 240 times more concentrated than the original strain. The presence of the epsilon toxin gene (etx) was verified by polymerase chain reaction. All clones were positive, including those determined to be negative by dot-blot tests, suggesting that mechanisms in addition to the presence of the etx gene can influence toxin production. The dot-blot test was efficient for the selection of toxigenic colonies of C. perfringens type D and demonstrated that homogeneous populations selected from toxigenic cultures produce higher titers of epsilon toxin.

A survey of knowledge, attitude, and practices of private retail pharmacies staff in tuberculosis care: study from Dera Ismail Khan City, Pakistan.

PubMed

Mustafa, Tehmina; Shahzad, Yasir; Kiani, Ayyaz

2018-01-01

In order to engage pharmacies in tuberculosis (TB) care, a survey was conducted in the Dera Ismail (DI) Khan City of the Khyber Pakhtoon Khwa province, Pakistan. The objectives were to; 1) characterize the retail pharmacies; 2) determine knowledge of the staff on various aspects of pulmonary TB; 3) determine practices related to the sale of anti-TB drugs, and referrals of presumptive TB patient, and willingness to participate in the National Tuberculosis Control Programme's (NTP) Directly Observed Treatment Short-Course (DOTS) strategy. A cross-sectional survey was conducted by using a structured questionnaire to collect data from pharmacy staff at all the private retail pharmacies of the DI khan city. All the interviewed staff ( n  = 82) were males, only 38% had formal training as pharmacist (5%) or as a pharmacy assistant (33%). Pharmacies established for a longer period were better staffed and had high customer load. About 92% of the interviewed staff knew that persistent cough is a symptom for TB, 82% knew that TB is diagnosed by examination of sputum. Almost 66% of the pharmacy staff did not know multi-drug resistance TB as a consequence of improper treatment. Those with formal training and longer experience in retail pharmacy had better knowledge of various aspects of TB as compared to the staff with no formal pharmacy training and lesser experience ( p  < 0.01). Only 57% were aware of NTP while only 30% had heard of the DOTS strategy. All reported sale of first-line TB drugs as fixed dose combinations. The majority (80%) referred presumptive TB patients to chest physicians and no patient was referred to the NTP. Nearly 83% of the interviewed staff was willing to be involved in TB control efforts by getting training and referring patients to the DOTS facility. There was shortage of professionally qualified and female staff in private retail pharmacies. Knowledge of professionally qualified staff about TB seemed sufficient to identify presumptive TB patients; however, their knowledge about NTP and DOTS was poor, and referral practices to NTP and DOTS centers were suboptimal. Majority of staff was willing to be involved in TB control efforts.

Short term inhalation toxicity of a liquid aerosol of glutaraldehyde-coated CdS/Cd(OH)2 core shell quantum dots in rats.

PubMed

Ma-Hock, L; Farias, P M A; Hofmann, T; Andrade, A C D S; Silva, J N; Arnaud, T M S; Wohlleben, W; Strauss, V; Treumann, S; Chaves, C R; Gröters, S; Landsiedel, R; van Ravenzwaay, B

2014-02-10

Quantum dots exhibit extraordinary optical and mechanical properties, and the number of their applications is increasing. In order to investigate a possible effect of coating on the inhalation toxicity of previously tested non-coated CdS/Cd(OH)2 quantum dots and translocation of these very small particles from the lungs, rats were exposed to coated quantum dots or CdCl2 aerosol (since Cd(2+) was present as impurity), 6h/d for 5 consecutive days. Cd content was determined in organs and excreta after the end of exposure and three weeks thereafter. Toxicity was determined by examination of broncho-alveolar lavage fluid and microscopic evaluation of the entire respiratory tract. There was no evidence for translocation of particles from the respiratory tract. Evidence of a minimal inflammatory process was observed by examination of broncho-alveolar lavage fluid. Microscopically, minimal to mild epithelial alteration was seen in the larynx. The effects observed with coated quantum dots, non-coated quantum dots and CdCl2 were comparable, indicating that quantum dots elicited no significant effects beyond the toxicity of the Cd(2+) ion itself. Compared to other compounds with larger particle size tested at similarly low concentrations, quantum dots caused much less pronounced toxicological effects. Therefore, the present data show that small particle sizes with corresponding high surfaces are not the only factor triggering the toxic response or translocation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Sandwich-dot enzyme-linked immunosorbent assay for the detection of canine distemper virus

PubMed Central

Li, Zhi; Zhang, Yanlong; Wang, Huiguo; Jin, Jinhua; Li, Wenzhe

2013-01-01

A sandwich-dot enzyme-linked immunosorbent assay (dot ELISA) was developed for the detection of canine distemper virus (CDV). In 56 dogs suspected to have CD the rates of detection of CDV antigen in samples of blood lymphocytes and palpebral conjunctiva by dot ELISA and ELISA were, respectively, 91% (49/54) and 81% (44/54) for the lymphocyte samples and 88% (28/32) and 75% (24/32) for the conjunctival samples. The CDV detection limits were 10 ng/50 μL for dot ELISA and 40 ng/50 μL for ELISA. The reliability of dot ELISA relative to electron microscopy was 96% with 22 samples: all 21 samples in which CDV particles were observed by electron microscopy yielded positive results with dot ELISA; the single sample in which particles were not observed yielded false-positive results with dot ELISA. The results indicate that the dot ELISA developed can serve as a reliable rapid diagnostic test in suspected cases of CD and also be useful for epidemiologic surveillance of the disease. PMID:24124274

Unmanned Aircraft Pilot Medical Certification Requirements

DTIC Science & Technology

2007-02-01

Security Classif. (of this page) 21. No. of Pages 22. Price Unclassified Unclassified 14 Form DOT F 1700.7 (8-72) Reproduction of completed...and hypnotics , anxiolytics, marijuana, cocaine, opiods, amphetamines, hallucinogens, and other psychoactive drugs or chemicals.) Disqualifying

Tuberculosis--triumph and tragedy.

PubMed

Singh, M M

2003-03-01

Tuberculosis has been making havoc worldwide with an 11.9 million cases to be involved by the year 2005. In India, about 2 million cases are infected every year. Regarding triumphs and tragedies in the control of tuberculosis some points as follows are discussed. (1) Tuberculosis Control Programmes from National Tuberculosis Programme (NTP) to Revised National Tuberculosis Control Programme (RNTCP) and Directly Observed Treatment, Short course (DOTS). (2) Problem of multidrug resistance (MDR) tuberculosis and (3) HIV and tuberculosis. DOTS being largely based on Indian research. It is now being applied worldwide. MDR is strictly a man made problem. Poor prescriptions, poor case management, lack of coordinated education and haphazard treatment research result in drug resistance. Treatment of MDR is difficult. The drug acceptability, tolerance and toxicity have to be considered. HIV and tuberculosis form a deadly duo. They mean more cases, more costs and more national losses.

Quantum dots in imaging, drug delivery and sensor applications

PubMed Central

Matea, Cristian T; Mocan, Teodora; Tabaran, Flaviu; Pop, Teodora; Mosteanu, Ofelia; Puia, Cosmin; Iancu, Cornel; Mocan, Lucian

2017-01-01

Quantum dots (QDs), also known as nanoscale semiconductor crystals, are nanoparticles with unique optical and electronic properties such as bright and intensive fluorescence. Since most conventional organic label dyes do not offer the near-infrared (>650 nm) emission possibility, QDs, with their tunable optical properties, have gained a lot of interest. They possess characteristics such as good chemical and photo-stability, high quantum yield and size-tunable light emission. Different types of QDs can be excited with the same light wavelength, and their narrow emission bands can be detected simultaneously for multiple assays. There is an increasing interest in the development of nano-theranostics platforms for simultaneous sensing, imaging and therapy. QDs have great potential for such applications, with notable results already published in the fields of sensors, drug delivery and biomedical imaging. This review summarizes the latest developments available in literature regarding the use of QDs for medical applications. PMID:28814860

Facile synthesis of blue-emitting carbon dots@mesoporous silica composite spheres

NASA Astrophysics Data System (ADS)

Guo, Ziying; Zhu, Zhenpeng; Zhang, Xinguo; Chen, Yibo

2018-02-01

This paper reported a facile and effective approach towards high-efficient composite luminophores by embedding blue-emitting N-doped carbon dots into spherical SiO2 matrix (CDs@SiO2). Mesoporous silica microspheres (r-CDs@MSN) with strong luminescence were synthesized by removing CTAB templates in CDs@SiO2 using reflux with acetone. The r-CDs@MSN possess a spherical morphology with smooth surface and a diameter of 130 nm, while it exhibits an excitation-independent blue emission peak at 440 nm with an internal quantum yield of 21.5%. BET result shows that the corresponding surface area and adsorption total pore volume are 156.27 m2/g and 0.682 cm3/g, which is suitable for the drugs loading and release. The results indicate that r-CDs@MSN might act as a potential fluorescent drug carrier.

Quantum dots in imaging, drug delivery and sensor applications.

PubMed

Matea, Cristian T; Mocan, Teodora; Tabaran, Flaviu; Pop, Teodora; Mosteanu, Ofelia; Puia, Cosmin; Iancu, Cornel; Mocan, Lucian

2017-01-01

Quantum dots (QDs), also known as nanoscale semiconductor crystals, are nanoparticles with unique optical and electronic properties such as bright and intensive fluorescence. Since most conventional organic label dyes do not offer the near-infrared (>650 nm) emission possibility, QDs, with their tunable optical properties, have gained a lot of interest. They possess characteristics such as good chemical and photo-stability, high quantum yield and size-tunable light emission. Different types of QDs can be excited with the same light wavelength, and their narrow emission bands can be detected simultaneously for multiple assays. There is an increasing interest in the development of nano-theranostics platforms for simultaneous sensing, imaging and therapy. QDs have great potential for such applications, with notable results already published in the fields of sensors, drug delivery and biomedical imaging. This review summarizes the latest developments available in literature regarding the use of QDs for medical applications.

Working towards TB elimination the WHO Regional Strategic Plan (2006-2015).

PubMed

Nair, Nani; Cooreman, Erwin

2006-03-01

DOTS has expanded rapidly in the South-East Asia Region over the period of the Partnership's first Global Plan (2001-2005), with almost 100% geographical coverage achieved in 2005. All countries have made impressive progress in improving coverage and quality. This progress has been made possible through strong political commitment and large investments in TB control for improved infrastructure, reliable drug supply, increased staffing, improved laboratory services, and intensified training and supervision. Accomplishing the objectives outlined in this document will require sustaining the progress in all countries and particularly in the five high burden countries for achieving major regional and global impact. National TB programmes will need to be supported to maintain or surpass the 70% case detection and 85% treatment success rates. The achievement of the TB-related targets linked to the MDGs will also depend on how effectively initiatives such as DOTS-Plus, PPM DOTS and interventions for TB/ HIV among others, are implemented. National governments and development partners must fulfill their commitments to mobilizing and sustaining adequate resources to support the full range of activities envisaged. The benefits of full and effective implementation of all the planned interventions would be substantial. These will result in 20 to 25 million TB cases being treated in DOTS program mes and more than 150 000 drug-resistant cases receiving treatment through DOTS-Plus during the period 2006-2015. In addition, at least 250 000 HIV-infected TB patients may also receive anti-retroviral therapy. As a consequence, the prevalence of TB is expected to fall below 175/100 000 and the number of TB deaths is expected to fall to between 100 000 and 150 000 per year. There would also be substantial economic benefits given that TB disproportionately affects adults in their most productive years. Considering these aspects, it is expected that the TB incidence will decline significantly during this period so that the Millennium Development Goals would be met by or ahead of 2015.

Community-based treatment of advanced HIV disease: introducing DOT-HAART (directly observed therapy with highly active antiretroviral therapy).

PubMed Central

Farmer, P.; Léandre, F.; Mukherjee, J.; Gupta, R.; Tarter, L.; Kim, J. Y.

2001-01-01

In 2000, acquired immunodeficiency syndrome (AIDS) overtook tuberculosis (TB) as the world's leading infectious cause of adult deaths. In affluent countries, however, AIDS mortality has dropped sharply, largely because of the use of highly active antiretroviral therapy (HAART). Antiretroviral agents are not yet considered essential medications by international public health experts and are not widely used in the poor countries where human immunodeficiency virus (HIV) takes its greatest toll. Arguments against the use of HAART have mainly been based on the high cost of medications and the lack of the infrastructure necessary for using them wisely. We re- examine these arguments in the setting of rising AIDS mortality in developing countries and falling drug prices, and describe a small community-based treatment programme based on lessons gained in TB control. With the collaboration of Haitian community health workers experienced in the delivery of home-based and directly observed treatment for TB, an AIDS-prevention project was expanded to deliver HAART to a subset of HIV patients deemed most likely to benefit. The inclusion criteria and preliminary results are presented. We conclude that directly observed therapy (DOT) with HAART, "DOT-HAART", can be delivered effectively in poor settings if there is an uninterrupted supply of high-quality drugs. PMID:11799447

Encapsulation of zinc-rifampicin complex into transferrin-conjugated silver quantum-dots improves its antimycobacterial activity and stability and facilitates drug delivery into macrophages

PubMed Central

Pati, Rashmirekha; Sahu, Rojalin; Panda, Jagannath; Sonawane, Avinash

2016-01-01

In order to improve the chemotherapy of tuberculosis, there is an urgent need to enhance the efficacy of existing agents and also to develop more efficient drug delivery systems. Here, we synthesized a novel anti-TB drug complex consisting of zinc and rifampicin (Zn-RIF), and encapsulated it into transferrin-conjugated silver quantum-dots (Zn-RIF-Tf-QD) to improve delivery in macrophages. Successful synthesis of Zn-RIF and Zn-RIF-Tf-QD was confirmed by UV/Vis-spectroscopy, TEM, FTIR, photoluminescence, XRD, XPS, and NMR. The sizes of silver QDs and transferrin-conjugated QDs were found to be in the range of 5–20 nm. Activity assays showed that Zn-RIF-Tf-QD exhibited 10-fold higher antibacterial activity against Mycobacterium smegmatis and Mycobacterium bovis-BCG as compared to Zn-RIF, RIF and Zn. Immunofluorescence studies showed that Zn-RIF-Tf-QD-conjugates were actively endocytosed by macrophages and dendritic cells, but not by lung epithelial cells. Treatment with Zn-RIF-Tf-QD efficiently killed mycobacteria residing inside macrophages without exhibiting cytotoxicity and genotoxicity. Moreover, the conjugates remained stable for upto 48 h, were taken up into the late endosomal compartment of macrophages, and released the drug in a sustainable manner. Our data demonstrate that Zn-RIF-Tf-QDs have a great potential as anti-TB drugs. In addition, transferrin-conjugated QDs may constitute an effective drug delivery system for tuberculosis therapy. PMID:27113139

Advanced Propulsion for Gun Launched Projectiles and Missiles: Phase 1 - Low Cost Flight Test Platform Development

DTIC Science & Technology

2009-11-30

Son blueberry fields as shown in Figure 113. All FAA and Maine DOT permits were acquired. Richard Willey was the designated LSO (Launch Safety...The launch area is on the Jasper Wyman & Son blueberry fields as shown in Figure 113. FAA and Maine DOT permits are required for flight testing

SB certification for mixture-based specification for flexible base.

DOT National Transportation Integrated Search

2012-10-01

Presentation topics: : Establish List of Qualified Producers; : Producers Responsible for Process Control/Quality Control; : Reduce TxDOT Sampling and Testing; : Expedite Aggregate Base Acceptance; : Share Responsibility (Producer/TxDOT) for Quality ...

Why do adults with dyslexia have poor global motion sensitivity?

PubMed

Conlon, Elizabeth G; Lilleskaret, Gry; Wright, Craig M; Stuksrud, Anne

2013-01-01

Two experiments aimed to determine why adults with dyslexia have higher global motion thresholds than typically reading controls. In Experiment 1, the dot density and number of animation frames presented in the dot stimulus were manipulated because of findings that use of a high dot density can normalize coherence thresholds in individuals with dyslexia. Dot densities were 14.15 and 3.54 dots/deg(2). These were presented for five (84 ms) or eight (134 ms) frames. The dyslexia group had higher coherence thresholds in all conditions than controls. However, in the high dot density, long duration condition, both reader groups had the lowest thresholds indicating normal temporal recruitment. These results indicated that the dyslexia group could sample the additional signals dots over space and then integrate these with the same efficiency as controls. In Experiment 2, we determined whether briefly presenting a fully coherent prime moving in either the same or opposite direction of motion to a partially coherent test stimulus would systematically increase and decrease global motion thresholds in the reader groups. When the direction of motion in the prime and test was the same, global motion thresholds increased for both reader groups. The increase in coherence thresholds was significantly greater for the dyslexia group. When the motion of the prime and test were presented in opposite directions, coherence thresholds were reduced in both groups. No group threshold differences were found. We concluded that the global motion processing deficit found in adults with dyslexia can be explained by undersampling of the target motion signals. This might occur because of difficulties directing attention to the relevant motion signals in the random dot pattern, and not a specific difficulty integrating global motion signals. These effects are most likely to occur in the group with dyslexia when more complex computational processes are required to process global motion.

Why do adults with dyslexia have poor global motion sensitivity?

PubMed Central

Conlon, Elizabeth G.; Lilleskaret, Gry; Wright, Craig M.; Stuksrud, Anne

2013-01-01

Two experiments aimed to determine why adults with dyslexia have higher global motion thresholds than typically reading controls. In Experiment 1, the dot density and number of animation frames presented in the dot stimulus were manipulated because of findings that use of a high dot density can normalize coherence thresholds in individuals with dyslexia. Dot densities were 14.15 and 3.54 dots/deg2. These were presented for five (84 ms) or eight (134 ms) frames. The dyslexia group had higher coherence thresholds in all conditions than controls. However, in the high dot density, long duration condition, both reader groups had the lowest thresholds indicating normal temporal recruitment. These results indicated that the dyslexia group could sample the additional signals dots over space and then integrate these with the same efficiency as controls. In Experiment 2, we determined whether briefly presenting a fully coherent prime moving in either the same or opposite direction of motion to a partially coherent test stimulus would systematically increase and decrease global motion thresholds in the reader groups. When the direction of motion in the prime and test was the same, global motion thresholds increased for both reader groups. The increase in coherence thresholds was significantly greater for the dyslexia group. When the motion of the prime and test were presented in opposite directions, coherence thresholds were reduced in both groups. No group threshold differences were found. We concluded that the global motion processing deficit found in adults with dyslexia can be explained by undersampling of the target motion signals. This might occur because of difficulties directing attention to the relevant motion signals in the random dot pattern, and not a specific difficulty integrating global motion signals. These effects are most likely to occur in the group with dyslexia when more complex computational processes are required to process global motion. PMID:24376414

Identification of prefrontal cortex (BA10) activation while performing Stroop test using diffuse optical tomography

NASA Astrophysics Data System (ADS)

Khadka, Sabin; Chityala, Srujan R.; Tian, Fenghua; Liu, Hanli

2011-03-01

Stroop test is commonly used as a behavior-testing tool for psychological examinations that are related to attention and cognitive control of the human brain. Studies have shown activations in Broadmann area 10 (BA10) of prefrontal cortex (PFC) during attention and cognitive process. The use of diffuse optical tomography (DOT) for human brain mapping is becoming more prevalent. In this study we expect to find neural correlates between the performed cognitive tasks and hemodynamic signals detected by a DOT system. Our initial observation showed activation of oxy-hemoglobin concentration in BA 10, which is consistent with some results seen by positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). Our study demonstrates the possibility of combining DOT with Stroop test to quantitatively investigate cognitive functions of the human brain at the prefrontal cortex.

A graphene quantum dot@Fe3O4@SiO2 based nanoprobe for drug delivery sensing and dual-modal fluorescence and MRI imaging in cancer cells.

PubMed

Su, Xiaoqian; Chan, Chunyu; Shi, Jingyu; Tsang, Ming-Kiu; Pan, Yi; Cheng, Changming; Gerile, Oudeng; Yang, Mo

2017-06-15

A novel graphene quantum dot (GQD)@Fe 3 O 4 @SiO 2 based nanoprobe was reported for targeted drug delivery, sensing, dual-modal imaging and therapy. Carboxyl-terminated GQD (C-GQD) was firstly conjugated with Fe 3 O 4 @SiO 2 and then functionalized with cancer targeting molecule folic acid (FA). DOX drug molecules were then loaded on GQD surface of Fe 3 O 4 @SiO 2 @GQD-FA nanoprobe via pi-pi stacking, which resulted in Fe 3 O 4 @SiO 2 @GQD-FA/DOX conjugates based on a FRET mechanism with GQD as donor molecules and DOX as acceptor molecules. Meanwhile, we successfully performed in vitro MRI and fluorescence imaging of living Hela cells and monitored intracellular drug release process using this Fe 3 O 4 @SiO 2 @GQD-FA/DOX nanoprobe. Cell viability study demonstrated the low cytotoxicity of Fe 3 O 4 @SiO 2 @GQD-FA nanocarrier and the enhanced therapeutic efficacy of Fe 3 O 4 @SiO 2 @GQD-FA/DOX nanoprobe for cancer cells. This luminomagnetic nanoprobe will be a potential platform for cancer accurate diagnosis and therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

Graphene Quantum Dots-Capped Magnetic Mesoporous Silica Nanoparticles as a Multifunctional Platform for Controlled Drug Delivery, Magnetic Hyperthermia, and Photothermal Therapy.

PubMed

Yao, Xianxian; Niu, Xingxing; Ma, Kexin; Huang, Ping; Grothe, Julia; Kaskel, Stefan; Zhu, Yufang

2017-01-01

A multifunctional platform is reported for synergistic therapy with controlled drug release, magnetic hyperthermia, and photothermal therapy, which is composed of graphene quantum dots (GQDs) as caps and local photothermal generators and magnetic mesoporous silica nanoparticles (MMSN) as drug carriers and magnetic thermoseeds. The structure, drug release behavior, magnetic hyperthermia capacity, photothermal effect, and synergistic therapeutic efficiency of the MMSN/GQDs nanoparticles are investigated. The results show that monodisperse MMSN/GQDs nanoparticles with the particle size of 100 nm can load doxorubicin (DOX) and trigger DOX release by low pH environment. Furthermore, the MMSN/GQDs nanoparticles can efficiently generate heat to the hyperthermia temperature under an alternating magnetic field or by near infrared irradiation. More importantly, breast cancer 4T1 cells as a model cellular system, the results indicate that compared with chemotherapy, magnetic hyperthermia or photothermal therapy alone, the combined chemo-magnetic hyperthermia therapy or chemo-photothermal therapy with the DOX-loaded MMSN/GQDs nanosystem exhibits a significant synergistic effect, resulting in a higher efficacy to kill cancer cells. Therefore, the MMSN/GQDs multifunctional platform has great potential in cancer therapy for enhancing the therapeutic efficiency. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Kelly, D L

The US Department of Energy (DOE) has been conducting, through several of its operating contractors, an evaluation and testing program to qualify Type A radioactive material packagings per US Department of Transportation (DOT) Specification 7A (DOT-7A) of the Code of Federal Regulations (CFR), Title 49, Part 178 (49 CFR 178). This document summarizes the evaluation and testing performed for all of the packagings successfully qualified in this program. This document supersedes DOE Evaluation Document for DOT-7A Type A Packaging (Edling 1987), originally issued in 1987 by Monsanto Research Corporation Mound Laboratory (MLM), Miamisburg, Ohio, for the Department of Energy, Securitymore » Evaluation Program (I)P-4. Mound Laboratory issued four revisions to the document between November 1988 and December 1989. In September 1989, the program was transferred to Westinghouse Hanford Company (Westinghouse Hanford) in Richland, Washington. One additional revision was issued in March 1990 by Westinghouse Hanford. This revision reflects the earlier material and incorporates a number of changes. Evaluation and testing activities on 1208 three DOT-7A Program Dockets resulted in the qualification of three new packaging configurations, which are incorporated herein and summarized. This document presents approximately 300 different packagings that have been determined to meet the requirements for a DOT-7A, type A packaging per 49 CFR 178.350.« less

Threshold matrix for digital halftoning by genetic algorithm optimization

NASA Astrophysics Data System (ADS)

Alander, Jarmo T.; Mantere, Timo J.; Pyylampi, Tero

1998-10-01

Digital halftoning is used both in low and high resolution high quality printing technologies. Our method is designed to be mainly used for low resolution ink jet marking machines to produce both gray tone and color images. The main problem with digital halftoning is pink noise caused by the human eye's visual transfer function. To compensate for this the random dot patterns used are optimized to contain more blue than pink noise. Several such dot pattern generator threshold matrices have been created automatically by using genetic algorithm optimization, a non-deterministic global optimization method imitating natural evolution and genetics. A hybrid of genetic algorithm with a search method based on local backtracking was developed together with several fitness functions evaluating dot patterns for rectangular grids. By modifying the fitness function, a family of dot generators results, each with its particular statistical features. Several versions of genetic algorithms, backtracking and fitness functions were tested to find a reasonable combination. The generated threshold matrices have been tested by simulating a set of test images using the Khoros image processing system. Even though the work was focused on developing low resolution marking technology, the resulting family of dot generators can be applied also in other halftoning application areas including high resolution printing technology.

Detection, eye–hand coordination and virtual mobility performance in simulated vision for a cortical visual prosthesis device

PubMed Central

Srivastava, Nishant R; Troyk, Philip R; Dagnelie, Gislin

2014-01-01

In order to assess visual performance using a future cortical prosthesis device, the ability of normally sighted and low vision subjects to adapt to a dotted ‘phosphene’ image was studied. Similar studies have been conduced in the past and adaptation to phosphene maps has been shown but the phosphene maps used have been square or hexagonal in pattern. The phosphene map implemented for this testing is what is expected from a cortical implantation of the arrays of intracortical electrodes, generating multiple phosphenes. The dotted image created depends upon the surgical location of electrodes decided for implantation and the expected cortical response. The subjects under tests were required to perform tasks requiring visual inspection, eye–hand coordination and way finding. The subjects did not have any tactile feedback and the visual information provided was live dotted images captured by a camera on a head-mounted low vision enhancing system and processed through a filter generating images similar to the images we expect the blind persons to perceive. The images were locked to the subject’s gaze by means of video-based pupil tracking. In the detection and visual inspection task, the subject scanned a modified checkerboard and counted the number of square white fields on a square checkerboard, in the eye–hand coordination task, the subject placed black checkers on the white fields of the checkerboard, and in the way-finding task, the subjects maneuvered themselves through a virtual maze using a game controller. The accuracy and the time to complete the task were used as the measured outcome. As per the surgical studies by this research group, it might be possible to implant up to 650 electrodes; hence, 650 dots were used to create images and performance studied under 0% dropout (650 dots), 25% dropout (488 dots) and 50% dropout (325 dots) conditions. It was observed that all the subjects under test were able to learn the given tasks and showed improvement in performance with practice even with a dropout condition of 50% (325 dots). Hence, if a cortical prosthesis is implanted in human subjects, they might be able to perform similar tasks and with practice should be able to adapt to dotted images even with a low resolution of 325 dots of phosphene. PMID:19458397

Noise measurement flight test of five light helicopters

DOT National Transportation Integrated Search

1993-07-01

The U.S. Department of Transportation, Federal Aviation Administration, (U.S.DOT/FAA), : along with the U.S. DOT, Research and Special Programs Administration, Volpe National : Transportation Systems Center (RSPA/Volpe Center) conducted a helicopter ...

Printer model for dot-on-dot halftone screens

NASA Astrophysics Data System (ADS)

Balasubramanian, Raja

1995-04-01

A printer model is described for dot-on-dot halftone screens. For a given input CMYK signal, the model predicts the resulting spectral reflectance of the printed patch. The model is derived in two steps. First, the C, M, Y, K dot growth functions are determined which relate the input digital value to the actual dot area coverages of the colorants. Next, the reflectance of a patch is predicted as a weighted combination of the reflectances of the four solid C, M, Y, K patches and their various overlays. This approach is analogous to the Neugebauer model, with the random mixing equations being replaced by dot-on-dot mixing equations. A Yule-Neilsen correction factor is incorporated to account for light scattering within the paper. The dot area functions and Yule-Neilsen parameter are chosen to optimize the fit to a set of training data. The model is also extended to a cellular framework, requiring additional measurements. The model is tested with a four color xerographic printer employing a line-on-line halftone screen. CIE L*a*b* errors are obtained between measurements and model predictions. The Yule-Neilsen factor significantly decreases the model error. Accuracy is also increased with the use of a cellular framework.

First demonstration of simultaneous measurement of beam current, beam position, and beam tilt on induction linac using combined B-dot monitor

NASA Astrophysics Data System (ADS)

He, Xiaozhong; Pang, Jian; Chen, Nan; Li, Qin; Dai, Wenhua; Ma, Chaofan; Zhao, Liangchao; Gao, Feng; Dai, Zhiyong

2017-06-01

The authors previously reported that the axial B-dots can be used to directly measure the beam tilt and demonstrated that the axial B-dots are applicable to a coaxial calibration stand. In this study, a combined B-dot monitor composed of four axial B-dot loops and four azimuthal ones is tested for the simultaneous measurement of the time-varying beam current, beam offset, and beam tilt at the output of the injector of the DRAGON-I induction linac. In the experiments, the beam offset and beam tilt at the position of the monitor are proportionally adjusted using a pair of steering coils. Eight waveforms acquired from the B-dot monitor are analyzed to reconstruct the time-varying beam current, beam offset, and beam tilt. The original signals of both the azimuthal B-dot and the axial B-dot ports change significantly with respect to the current applied to the steering coils. The measured beam tilt is linearly dependent on the current applied to the steering coils and agrees well with the measured beam offset.

Naturalistic Assessment of Everyday Functioning in Individuals with Mild Cognitive Impairment: The Day Out Task

PubMed Central

Schmitter-Edgecombe, Maureen; McAlister, Courtney; Weakley, Alyssa

2012-01-01

Objective The Day Out Task (DOT), a naturalistic task that requires multitasking in a real-world setting, was used to examine everyday functioning in individuals with mild cognitive impairment (MCI). Method Thirty-eight participants with MCI and 38 cognitively healthy older adult controls prioritized, organized, initiated and completed a number of subtasks in a campus apartment to prepare for a day out (e.g., determine and gather change for bus, bring a magazine). Participants also completed tests assessing cognitive constructs important in multitasking (i.e., retrospective memory, prospective memory, planning). Results Compared to controls, the MCI group required more time to complete the DOT and demonstrated poorer task accuracy, performing more subtasks incompletely and inaccurately. Despite poorer DOT task accuracy, the MCI and control groups approached completion of the DOT in a similar manner. For the MCI group, retrospective memory was a unique predictor of the number of subtasks left incomplete and inaccurate, while prospective memory was a unique predictor of DOT sequencing. The DOT measures, but not the cognitive tests, were predictive of knowledgeable informant report of everyday functioning. Conclusions These findings suggest that difficulty remembering and keeping track of multiple goals and subgoals may contribute to the poorer performance of individuals with MCI in complex everyday situations. PMID:22846035

Single quantum dot tracking reveals the impact of nanoparticle surface on intracellular state.

PubMed

Zahid, Mohammad U; Ma, Liang; Lim, Sung Jun; Smith, Andrew M

2018-05-08

Inefficient delivery of macromolecules and nanoparticles to intracellular targets is a major bottleneck in drug delivery, genetic engineering, and molecular imaging. Here we apply live-cell single-quantum-dot imaging and tracking to analyze and classify nanoparticle states after intracellular delivery. By merging trajectory diffusion parameters with brightness measurements, multidimensional analysis reveals distinct and heterogeneous populations that are indistinguishable using single parameters alone. We derive new quantitative metrics of particle loading, cluster distribution, and vesicular release in single cells, and evaluate intracellular nanoparticles with diverse surfaces following osmotic delivery. Surface properties have a major impact on cell uptake, but little impact on the absolute cytoplasmic numbers. A key outcome is that stable zwitterionic surfaces yield uniform cytosolic behavior, ideal for imaging agents. We anticipate that this combination of quantum dots and single-particle tracking can be widely applied to design and optimize next-generation imaging probes, nanoparticle therapeutics, and biologics.

Synthesis of workload reduction strategies for construction inspection.

DOT National Transportation Integrated Search

2008-10-01

State departments of transportation (DOTs) have seen significant funding increases throughout the past decade. The : additional funding has also brought about an increase in the construction inspection and testing workload, but the : DOTs have not se...

Development of Multifunctional Nanoparticles for Cancer Therapy Applications

NASA Astrophysics Data System (ADS)

Huth, Christopher

The focus of this thesis is the functionalization and tailoring of nanoparticle surfaces to perform specific objectives in a biological environment. The nanoparticles examined include carbon nanotubes (CNTs), superparamagnetic iron oxide nanoparticles and superparamagnetic iron oxide nanocomposites. The unique nanomaterials have been developed to address continued issues in cancer therapy, including cancer diagnosis and efficient drug delivery. CNT surfaces were modified by plasma polymerization, providing functional groups for conjugation. Luminescent amine labeled quantum dots were fixed to the surface of the CNTs to aid in cancer diagnosis by in vivo imaging. Mice, injected with the quantum dot functionalized carbon nanotubes, were imaged displaying the in vivo imaging capability. In addition, the drug loading and drug release capabilities were examined by incorporating the drug paclitaxel into PLGA-coated CNTs, which showed much higher cytotoxicity to PC-3MM2 human prostate carcinoma cells compared to CNTs without paclitaxel. Paclitaxel was loaded at 112.5 microg/mg of PLGA-coated CNTs. Iron oxide nanocomposites were functionalized with quantum dots for diagnosis applications. Because the nanocomposites contain iron oxide, the nanoparticle provides the opportunity for magnetic hyperthermia, creating a unique material for diagnosis and therapy. Mice, injected with the quantum dot functionalized iron oxide nanocomposites, were imaged displaying the in vivo imaging capability. The magnetic hyperthermic property of the quantum dot functionalized nanocomposites was observed with the attainment of temperatures above 50°C during exposure to an alternating magnetic field. Thermoresponsive nanoparticles were prepared by immobilizing a 2 - 3 nm thick phospholipid layer on the surface of superparamagnetic Fe3O 4 nanoparticles via high affinity avidin/biotin interactions. Morphological and physicochemical surface properties were assessed using TEM, confocal laser scanning microscopy, differential scanning calorimetry, and ATR-FTIR. The zeta potential of Fe3O4 colloids in phosphate buffered saline (PBS) decreased from -23.6 to -5.0 mV as a consequence of phospholipid immobilization. Hyperthermia-relevant temperatures greater than 40°C were achieved within 10--15 min using a 7-mT magnetic field alternating at a frequency of 1MHz. Loading of the surface-associated phospholipid layer with the hydrophobic dye dansylcadaverine was accomplished at an efficiency of 479 ng/mg Fe3O4. Release of this drug surrogate was temperature-dependent, resulting in a 2.5-fold greater release rate when nanoparticles were exposed to temperatures above the experimentally determined melting temperature of 39.7°C. In vitro cytotoxicity studies by release of the cytotoxic drug, doxorubicin, from the thermoresponsive nanoparticles was lastly intended. However, colloidal stability became an issue, prompting a thorough review of nanoparticle stabilization. Factors affecting stabilization, including dispersant, the nanoparticle, and the thermoresponsive coating, were characterized by dynamic light scattering and zeta potential. PBS was compared to two dispersants containing lower ionic concentrations, HBSS and HEPES, using the original iron oxide nanoparticles compared to an iron oxide nanocomposite. The nanocomposite in the HEPES buffer displayed the greatest stability with a zeta potential of -30.47 mV and particle size of 155.4 nm. Stabilization of the immobilized phospholipid bilayer was examined with and without incorporation of the cationic lipid stearylamine. Zeta potential (33.6 mV) and size (315 nm) data indicate that stearylamine incorporated DPPC coated nanoparticles provide better stability.

Development of a one-step immunochromatographic strip test using gold nanoparticles for the rapid detection of Salmonella typhi in human serum.

PubMed

Preechakasedkit, Pattarachaya; Pinwattana, Kulwadee; Dungchai, Wijitar; Siangproh, Weena; Chaicumpa, Wanpen; Tongtawe, Pongsri; Chailapakul, Orawon

2012-01-15

An immunochromatographic strip test using gold nanoparticles was developed for the rapid detection of Salmonella typhi (S. typhi) in human serum. The strip test based on the principle of sandwich immunoassay by the specific binding of antigens from S. typhi O901 and antibody of S. typhi O901 on a nitrocellulose membrane. Antibody-gold nanoparticle conjugate was used as the label and was coated onto a glass fiber membrane, which was used as a conjugate pad. To create a test and control zone, antibody of S. typhi O901 and an anti-IgG were dotted on the nitrocellulose membrane, respectively. Positive samples were displayed as red dots at the test and control zones of the nitrocellulose membrane, while negative samples resulted in a red dot only in the control zone. The limit of detection (LOD) was found to be 1.14×10(5) cfu mL(-1), which could be visually detected by the naked eye within 15 min. This strip test provided a lower detection limit and analysis time than a dot blot immunoassay (8.88×10(6) cfu mL(-1) for LOD and 110 min for reaction time). In addition, our immunochromatographic strip test was employed to detect S. typhi in human serum effectively, with high accuracy. This strip test offers great promise for a rapid, simple and low-cost analysis of S. typhi. Copyright © 2011 Elsevier B.V. All rights reserved.

Subdecoherence time generation and detection of orbital entanglement in quantum dots.

PubMed

Brange, F; Malkoc, O; Samuelsson, P

2015-05-01

Recent experiments have demonstrated subdecoherence time control of individual single-electron orbital qubits. Here we propose a quantum-dot-based scheme for generation and detection of pairs of orbitally entangled electrons on a time scale much shorter than the decoherence time. The electrons are entangled, via two-particle interference, and transferred to the detectors during a single cotunneling event, making the scheme insensitive to charge noise. For sufficiently long detector dot lifetimes, cross-correlation detection of the dot charges can be performed with real-time counting techniques, providing for an unambiguous short-time Bell inequality test of orbital entanglement.

Comparison of two quantum dots for bioluminescence resonance energy transfer based on nucleic acid detection

NASA Astrophysics Data System (ADS)

Zhang, Daohong

2017-05-01

The performance of two commercially available quantum dots, quantum dot 605 (Qd605) and quantum dot 625 (Qd625), was tested and compared in the sensing system developed by our group previously. The sandwich format sensing system employed Renilla luciferase (Rluc) and quantum dots (Qds), could report the presence of targets with increasing bioluminescent resonance energy transfer (BRET) signal. The best spacing between the Rluc and Qds probes were 15 nucleotides. Both of Qd605 and Qd625 sensing system could quantify nucleic acid targets through 1-min hybridization from 0.2 picomoles. However, the Qd625 system showed higher BRET signal and better selectivity. Therefore, Qd625 is a better choice in this system compared to Qd605.

Environmental mimics and the Lvh type IVA secretion system contribute to virulence-related phenotypes of Legionella pneumophila.

PubMed

Bandyopadhyay, Purnima; Liu, Shuqing; Gabbai, Carolina B; Venitelli, Zeah; Steinman, Howard M

2007-02-01

Legionella pneumophila, the causative organism of Legionnaires' disease, is a fresh-water bacterium and intracellular parasite of amoebae. This study examined the effects of incubation in water and amoeba encystment on L. pneumophila strain JR32 and null mutants in dot/icm genes encoding a type IVB secretion system required for entry, delayed acidification of L. pneumophila-containing phagosomes, and intracellular multiplication when stationary-phase bacteria infect amoebae and macrophages. Following incubation of stationary-phase cultures in water, mutants in dotA and dotB, essential for function of the type IVB secretion system, exhibited entry and delay of phagosome acidification comparable to that of strain JR32. Following encystment in Acanthamoeba castellanii and reversion of cysts to amoeba trophozoites, dotA and dotB mutants exhibited intracellular multiplication in amoebae. The L. pneumophila Lvh locus, encoding a type IVA secretion system homologous to that in Agrobacterium tumefaciens, was required for restoration of entry and intracellular multiplication in dot/icm mutants following incubation in water and amoeba encystment and was required for delay of phagosome acidification in strain JR32. These data support a model in which the Dot/Icm type IVB secretion system is conditionally rather than absolutely required for L. pneumophila virulence-related phenotypes. The data suggest that the Lvh type IVA secretion system, previously thought to be dispensable, is involved in virulence-related phenotypes under conditions mimicking the spread of Legionnaires' disease from environmental niches. Since environmental amoebae are implicated as reservoirs for an increasing number of environmental pathogens and for drug-resistant bacteria, the environmental mimics developed here may be useful in virulence studies of other pathogens.

[Effect of DOT1L gene silence on proliferation of acute monocytic leukemia cell line THP-1].

PubMed

Zhang, Yu-Juan; Li, Hua-Wen; Chang, Guo-Qiang; Zhang, Hong-Ju; Wang, Jian; Lin, Ya-Ni; Zhou, Jia-Xi; Li, Qing-Hua; Pang, Tian-Xiang

2013-08-01

This study was aimed to investigate the influence of short hairpin RNA (shRNA) on proliferation of human leukemia cell line THP-1. The shRNA targeting the site 732-752 of DOT1L mRNA was designed and chemically synthesized, then a single-vector lentiviral, tet-inducible shRNA-DOT1L system (Plko-Tet-On) was generated. Thereafter, the THP-1 cells with lentivirus were infected to create stable cell line with regulatable shRNA expression. The expression of DOT1L in the THP-1 cell line was assayed by RT-PCR. Effect of shRNA-DOT1L on the proliferation of THP-1 cells was detected with MTT method,and the change of colony forming potential of THP-1 cells was analyzed by colony forming unit test. Cell cycle distribution was tested by flow cytometry. The results indicated that the expression of DOT1L was statistically lower than that in the control groups. The proliferation and colony forming capacity of THP-1 cells were significantly inhibited. The percentage of cells at G0/G1 phase increased in THP-1/shRNA cells treated with Dox while the percentage of cells at S phase significantly decreased as compared with that in the control group. It is concluded that the shRNA targeting DOT1L can effectively inhibit the proliferation of acute monocytic leukemia cell line THP-1.

Use of a Novel Artificial Intelligence Platform on Mobile Devices to Assess Dosing Compliance in a Phase 2 Clinical Trial in Subjects With Schizophrenia

PubMed Central

2017-01-01

Background Accurately monitoring and collecting drug adherence data can allow for better understanding and interpretation of the outcomes of clinical trials. Most clinical trials use a combination of pill counts and self-reported data to measure drug adherence, despite the drawbacks of relying on these types of indirect measures. It is assumed that doses are taken, but the exact timing of these events is often incomplete and imprecise. Objective The objective of this pilot study was to evaluate the use of a novel artificial intelligence (AI) platform (AiCure) on mobile devices for measuring medication adherence, compared with modified directly observed therapy (mDOT) in a substudy of a Phase 2 trial of the α7 nicotinic receptor agonist (ABT-126) in subjects with schizophrenia. Methods AI platform generated adherence measures were compared with adherence inferred from drug concentration measurements. Results The mean cumulative pharmacokinetic adherence over 24 weeks was 89.7% (standard deviation [SD] 24.92) for subjects receiving ABT-126 who were monitored using the AI platform, compared with 71.9% (SD 39.81) for subjects receiving ABT-126 who were monitored by mDOT. The difference was 17.9% (95% CI -2 to 37.7; P=.08). Conclusions Using drug levels, this substudy demonstrates the potential of AI platforms to increase adherence, rapidly detect nonadherence, and predict future nonadherence. Subjects monitored using the AI platform demonstrated a percentage change in adherence of 25% over the mDOT group. Subjects were able to use the technology successfully for up to 6 months in an ambulatory setting with early termination rates that are comparable to subjects outside of the substudy. Trial Registration ClinicalTrials.gov NCT01655680 https://clinicaltrials.gov/ct2/show/NCT01655680?term=NCT01655680 PMID:28223265

Use of a Novel Artificial Intelligence Platform on Mobile Devices to Assess Dosing Compliance in a Phase 2 Clinical Trial in Subjects With Schizophrenia.

PubMed

Bain, Earle E; Shafner, Laura; Walling, David P; Othman, Ahmed A; Chuang-Stein, Christy; Hinkle, John; Hanina, Adam

2017-02-21

Accurately monitoring and collecting drug adherence data can allow for better understanding and interpretation of the outcomes of clinical trials. Most clinical trials use a combination of pill counts and self-reported data to measure drug adherence, despite the drawbacks of relying on these types of indirect measures. It is assumed that doses are taken, but the exact timing of these events is often incomplete and imprecise. The objective of this pilot study was to evaluate the use of a novel artificial intelligence (AI) platform (AiCure) on mobile devices for measuring medication adherence, compared with modified directly observed therapy (mDOT) in a substudy of a Phase 2 trial of the α7 nicotinic receptor agonist (ABT-126) in subjects with schizophrenia. AI platform generated adherence measures were compared with adherence inferred from drug concentration measurements. The mean cumulative pharmacokinetic adherence over 24 weeks was 89.7% (standard deviation [SD] 24.92) for subjects receiving ABT-126 who were monitored using the AI platform, compared with 71.9% (SD 39.81) for subjects receiving ABT-126 who were monitored by mDOT. The difference was 17.9% (95% CI -2 to 37.7; P=.08). Using drug levels, this substudy demonstrates the potential of AI platforms to increase adherence, rapidly detect nonadherence, and predict future nonadherence. Subjects monitored using the AI platform demonstrated a percentage change in adherence of 25% over the mDOT group. Subjects were able to use the technology successfully for up to 6 months in an ambulatory setting with early termination rates that are comparable to subjects outside of the substudy. ClinicalTrials.gov NCT01655680 https://clinicaltrials.gov/ct2/show/NCT01655680?term=NCT01655680. ©Earle E Bain, Laura Shafner, David P Walling, Ahmed A Othman, Christy Chuang-Stein, John Hinkle, Adam Hanina. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 21.02.2017.

Performance of the dot product function in radiative transfer code SORD

NASA Astrophysics Data System (ADS)

Korkin, Sergey; Lyapustin, Alexei; Sinyuk, Aliaksandr; Holben, Brent

2016-10-01

The successive orders of scattering radiative transfer (RT) codes frequently call the scalar (dot) product function. In this paper, we study performance of some implementations of the dot product in the RT code SORD using 50 scenarios for light scattering in the atmosphere-surface system. In the dot product function, we use the unrolled loops technique with different unrolling factor. We also considered the intrinsic Fortran functions. We show results for two machines: ifort compiler under Windows, and pgf90 under Linux. Intrinsic DOT_PRODUCT function showed best performance for the ifort. For the pgf90, the dot product implemented with unrolling factor 4 was the fastest. The RT code SORD together with the interface that runs all the mentioned tests are publicly available from ftp://maiac.gsfc.nasa.gov/pub/skorkin/SORD_IP_16B (current release) or by email request from the corresponding (first) author.

An aptamer folding-based sensory platform decorated with nanoparticles for simple cocaine testing.

PubMed

Guler, Emine; Bozokalfa, Guliz; Demir, Bilal; Gumus, Zinar Pinar; Guler, Bahar; Aldemir, Ebru; Timur, Suna; Coskunol, Hakan

2017-04-01

The consumption of illicit drugs such as cannabis, cocaine, and amphetamines is still a major health and social problem, creating an abuse in adults especially. Novel techniques which estimate the drug of abuse are needed for the detection of newly revealed psychoactive drugs. Herein, we have constructed a combinatorial platform by using quantum dots (QDs) and gold nanoparticles (AuNPs) as well as a functional aptamer which selectively recognizes cocaine and its metabolite benzoylecgonine (BE). We have called it an aptamer folding-based sensory device (AFSD). For the fabrication of AFSD, QDs were initially immobilized onto the poly-L-lysine coated μ-well surfaces. Then, the AuNP-aptamer conjugates were bound to the QDs. The addition of cocaine or BE caused a change in the aptamer structure which induced the close interaction of AuNPs with the QDs. Hence, quenching of the fluorescence of QDs was observed depending on the analyte amount. The linearity of cocaine and BE was 1.0-10 nM and 1.0-25 μM, respectively. Moreover, the limits of detection for cocaine and BE were calculated as 0.138 nM and 1.66 μM. The selectivity was tested by using different interfering substances (methamphetamine, bovine serum albumin, codeine, and 3-acetamidophenol). To investigate the use of AFSD in artificial urine matrix, cocaine/BE spiked samples were applied. Also, confirmatory analyses by using high performance liquid chromatography were performed. It is shown that AFSD has a good potential for testing the cocaine abuse and can be easily adapted for detection of various addictive drugs by changing the aptamer according to desired analytes. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

A new computer program for mass screening of visual defects in preschool children.

PubMed

Briscoe, D; Lifshitz, T; Grotman, M; Kushelevsky, A; Vardi, H; Weizman, S; Biedner, B

1998-04-01

To test the effectiveness of a PC computer program for detecting vision disorders which could be used by non-trained personnel, and to determine the prevalence of visual impairment in a sample population of preschool children in the city of Beer-Sheba, Israel. 292 preschool children, aged 4-6 years, were examined in the kindergarten setting, using the computer system and "gold standard" tests. Visual acuity and stereopsis were tested and compared using Snellen type symbol charts and random dot stereograms respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and kappa test were evaluated. A computer pseudo Worth four dot test was also performed but could not be compared with the standard Worth four dot test owing to the inability of many children to count. Agreement between computer and gold standard tests was 83% and 97.3% for visual acuity and stereopsis respectively. The sensitivity of the computer stereogram was only 50%, but it had a specificity of 98.9%, whereas the sensitivity and specificity of the visual acuity test were 81.5% and 83% respectively. The positive predictive value of both tests was about 63%. 27.7% of children tested had a visual acuity of 6/12 or less and stereopsis was absent in 28% using standard tests. Impairment of fusion was found in 5% of children using the computer pseudo Worth four dot test. The computer program was found to be stimulating, rapid, and easy to perform. The wide availability of computers in schools and at home allow it to be used as an additional screening tool by non-trained personnel, such as teachers and parents, but it is not a replacement for standard testing.

[Medical treatment support to tuberculous patients--from the standpoint of community support].

PubMed

2001-11-01

A symposium with "Medical Treatment Support to Tuberculous Patients--From the standpoint of community support" as its theme was held at the 76th Annual Meeting of the Japanese Society for Tuberculosis (April 20, 2001). "Once, It is infected with tuberculosis, one have to complete medication with a sensitive antituberculosis drug by observing the prescribed dose and duration for successful treatment". For this to be promoted community, it is necessary that (1) to manage patient's medication by medical facilities, (2) to support patient's medication by health center and (3) to support patient's living by welfare offices. Not that each facilities takes such responsibilities alone, but various community must fulfill them continuously in liaison with one another. On what measures should be taken to that end, reports based on practical examples from Nagoya City, Yokohama City and Kanagawa Prefecture have been compiled as follows. 1. It was in-office liaison by conference that supported the DOTS activities of health nurses. 2. It is cooperating, without health, medical treatment, and welfare going out, as follows. (1) A system for hospitals and clinics to carry out DOTS treatment consistently has been kept in good condition. (2) For a patient to take a drug in front of a nurse has become common, causing the patients to be motivated. (3) Assignment of MSW and nurses in charge of DOTS sent from hospitals has make it possible to offer or exchange information smoothly among those concerned. (4) A system for many persons concerned to support patients timely has been kept in good condition. This resulted in an increase in the cure rate of tuberculosis in the areas which have day laborers' lodgings. 3. By DOTS for in-patients, the number of self-discharges has decreased by 1/3, and the treatment completion rate was 94%. 4. In promotion of DOTS for the patients who have health problems other than tuberculosis, the role MSW plays is great. 5. As conditions for supporting DOTS promotion, it is necessary to create a system by which to stabilize the living of the patient himself, guarantee earnings to support it and dissolve the living problem faced by the patient. 6. Introduction of the "early guidance system for the patients in whom the treatment of tuberculosis" was discontinued has strengthened the liaison between health offices and medical facilities, has led to early detection in persons yet to receive medical treatment and resumption of medical treatment, making it possible to deal with problem cases effectively on a priority basis. It has been confirmed that liaison between health, medical service and welfare for community support of the treatment of tuberculous patients who live in that community resulted in improvement of clinical results of tuberculous patients. In this connection, Dr. Shirai advised "For a tuberculous patient to form a habit of taking a drug wherever he lives needs to be recognized as a major subject". He presented the forcible yell. "Any local government office has the homeless. I want you to make efforts so that DOTS be given to all the tuberculous persons. If there is any problem, I am ready to give advice."

Fluorescent carbon dot-gated multifunctional mesoporous silica nanocarriers for redox/enzyme dual-responsive targeted and controlled drug delivery and real-time bioimaging.

PubMed

Wang, Ying; Cui, Yu; Zhao, Yating; He, Bing; Shi, Xiaoli; Di, Donghua; Zhang, Qiang; Wang, Siling

2017-08-01

A distinctive and personalized nanocarrier is described here for controlled and targeted antitumor drug delivery and real-time bioimaging by combining a redox/enzyme dual-responsive disulfide-conjugated carbon dot with mesoporous silica nanoparticles (MSN-SS-CD HA ). The carbon dot with controlling and targeting abilities was prepared through a polymerizing reaction by applying citric acid and HA as starting materials (named CD HA ). The as-prepared MSN-SS-CD HA exhibited not only superior photostability and excellent biocompatibility, but also the ability to target A549 cells with overexpression of CD44 receptors. Upon loading the antitumor drug, doxorubicin (DOX), into the mesoporous channels of MSN nanoparticles, CD HA with a diameter size of 3nm completely blocked the pore entrance of DOX-encapsulated MSN nanoparticles with a pore size of about 3nm, thus preventing the premature leakage of DOX and increasing the antitumor activity until being triggered by specific stimuli in the tumor environment. The results of the cell imaging and cytotoxicity studies demonstrated that the redox/enzyme dual-responsive DOX-encapsulated MSN-SS-CD HA nanoparticles can selectively deliver and control the release of DOX into tumor cells. Ex vivo fluorescence images showed a much stronger fluorescence of MSN-SS-CD HA -DOX in the tumor site than in normal tissues, greatly facilitating the accumulation of DOX in the target tissue. However, its counterpart, MSN-SH-DOX exhibited no or much lower tumor cytotoxicity and drug accumulation in tumor tissue. In addition, MSN-SS-CD was also used as a control to investigate the ability of MSN-SS-CD HA to target A549 cells. The results obtained indicated that MSN-SS-CD HA possessed a higher cellular uptake through the CD44 receptor-mediated endocytosis compared with MSN-SS-CD in the A549 cells. Such specific redox/enzyme dual-responsive targeted nanocarriers are a useful strategy achieving selective controlled and targeted delivery of therapeutic reagents with real-time bioimaging, and may also facilitate the development of drug delivery systems for a number of clinical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Prop-fan noise propagation

DOT National Transportation Integrated Search

1989-02-07

This report summarizes studies of enroute propfan noise propagation involving noise data obtained by DOT/TSC at ground stations during fly-over tests on October 30-31, 1987. These data have been analsyzed by DOT/TSC for comparison with in flight data...

White paper : Mn/DOT driver acceptance : IVI FOT evaluation report

DOT National Transportation Integrated Search

2003-06-30

This white paper provides findings from surveys and interviews for the evaluation of driver acceptance as a component of Battelles independent evaluation of the Mn/DOT Intelligent Vehicle Initiative (IVI) Field Operational Test (FOT), sponsored by th...

Mitigating Cyber Security Risk in Satellite Ground Systems

DTIC Science & Technology

2015-04-01

because cyber security in government remains shrouded in secrecy. However, using the Defense Operational Test and Evaluation Office’s (DOT& E ) FY14...report on cybersecurity one grasps the seriousness of the problem. DOT& E reported only 85% of networks in DoD were compliant with the cyber...security regulations discussed later in this paper. Not until compliance is near 100% could DOT& E conceive with confidence that DoD networks were safe

Eruptive Facial Postinflammatory Lentigo: Clinical and Dermatoscopic Features.

PubMed

Cabrera, Raul; Puig, Susana; Larrondo, Jorge; Castro, Alex; Valenzuela, Karen; Sabatini, Natalia

2016-11-01

The face has not been considered a common site of fixed drug eruption, and the authors lack dermatoscopic studies of this condition on the subject. The authors sought to characterize clinical and dermatoscopic features of 8 cases of an eruptive facial postinflammatory lentigo. The authors conducted a retrospective review of 8 cases with similar clinical and dermatoscopic findings seen from 2 medical centers in 2 countries during 2010-2014. A total of 8 patients (2 males and 6 females) with ages that ranged from 34 to 62 years (mean: 48) presented an abrupt onset of a single facial brown-pink macule, generally asymmetrical, with an average size of 1.9 cm. after ingestion of a nonsteroidal antiinflammatory drugs that lasted for several months. Dermatoscopy mainly showed a pseudonetwork or uniform areas of brown pigmentation, brown or blue-gray dots, red dots and/or telangiectatic vessels. In the epidermis, histopathology showed a mild hydropic degeneration and focal melanin hyperpigmentation. Melanin can be found freely in the dermis or laden in macrophages along with a mild perivascular mononuclear infiltrate. The authors describe eruptive facial postinflammatory lentigo as a new variant of a fixed drug eruption on the face.

Electroinduced Delivery of Hydrogel Nanoparticles in Colon 26 Cells, Visualized by Confocal Fluorescence System.

PubMed

Atanasova, Severina; Nikolova, Biliana; Murayama, Shuhei; Stoyanova, Elena; Tsoneva, Iana; Zhelev, Zhivko; Aoki, Ichio; Bakalova, Rumiana

2016-09-01

Nano-scale drug delivery systems (nano-DDS) are under intense investigation. Nano-platforms are developed for specific administration of small molecules, drugs, genes, contrast agents [quantum dots (QDs)] both in vivo and in vitro. Electroporation is a biophysical phenomenon which consists of the application of external electrical pulses across the cell membrane. The aim of this study was to research electro-assisted Colon 26 cell line internalization of QDs and QD-loaded nano-hydrogels (polymersomes) visualized by confocal microscopy and their influence on cell viability. The experiments were performed on the Colon 26 cancer cell line, using a confocal fluorescent imaging system and cell viability test. Electroporation facilitated the delivery of nanoparticles in vivo. We demonstrated increased voltage-dependent delivery of nanoparticles into cells after electrotreatment, without significant cell viability reduction. The delivery and retention of the polymersomes in vitro is a promising tool for future cancer treatment strategies and nanomedcine. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Dot-Blot Immunoassay of Fasciola gigantica Infection using 27 kDa and Adult Worm Regurge Antigens in Egyptian Patients

PubMed Central

Kamel, Hanan H.; Saad, Ghada A.

2013-01-01

The purpose of the present study was to evaluate the potential role of the 27-Kilodalton (KDa) antigen versus Fasciola gigantica adult worm regurge antigens in a DOT-Blot assay and to assess this assay as a practical tool for diagnosis fascioliasis in Egyptian patients. Fasciola gigantica antigen of an approximate molecular mass 27-(KDa) was obtained from adult worms by a simple elution SDS-PAGE. A Dot-Blot was developed comparatively to adult worm regurge antigens for the detection of specific antibodies from patients infected with F. gigantica in Egypt. Control sera were obtained from patients with other parasitic infections and healthy volunteers to assess the test and compare between the antigens. The sensitivity, specificity, positive and negative predictive values of Dot-Blot using the adult worm regurge were 80%, 90%, 94.1%, and 69.2% respectively, while those using 27-KDa were 100% which confirms the diagnostic potential of this antigen. All patients infected with Fasciola were positive, with cross reactivity reported with Schistosoma mansoni serum samples. This 27-KDa Dot-Blot assay showed to be a promising test which can be used for serodiagnosis of fascioliasis in Egyptian patients especially, those presenting with hepatic disease. It is specific, sensitive and easy to perform method for the rapid diagnosis particularly when more complex laboratory tests are unavailable. PMID:23710084

Dot-blot immunoassay of Fasciola gigantica infection using 27 kDa and adult worm regurge antigens in Egyptian patients.

PubMed

Kamel, Hanan H; Saad, Ghada A; Sarhan, Rania M

2013-04-01

The purpose of the present study was to evaluate the potential role of the 27-Kilodalton (KDa) antigen versus Fasciola gigantica adult worm regurge antigens in a DOT-Blot assay and to assess this assay as a practical tool for diagnosis fascioliasis in Egyptian patients. Fasciola gigantica antigen of an approximate molecular mass 27-(KDa) was obtained from adult worms by a simple elution SDS-PAGE. A Dot-Blot was developed comparatively to adult worm regurge antigens for the detection of specific antibodies from patients infected with F. gigantica in Egypt. Control sera were obtained from patients with other parasitic infections and healthy volunteers to assess the test and compare between the antigens. The sensitivity, specificity, positive and negative predictive values of Dot-Blot using the adult worm regurge were 80%, 90%, 94.1%, and 69.2% respectively, while those using 27-KDa were 100% which confirms the diagnostic potential of this antigen. All patients infected with Fasciola were positive, with cross reactivity reported with Schistosoma mansoni serum samples. This 27-KDa Dot-Blot assay showed to be a promising test which can be used for serodiagnosis of fascioliasis in Egyptian patients especially, those presenting with hepatic disease. It is specific, sensitive and easy to perform method for the rapid diagnosis particularly when more complex laboratory tests are unavailable.

Twin Cities ramp meter evaluation : evaluation plan

DOT National Transportation Integrated Search

2000-09-25

The Minnesota Department of Transportation (Mn/DOT) uses ramp meters to manage freeway access on approximately 210 miles of freeways in the Twin Cities metropolitan area. Mn/DOT first tested ramp meters in 1969 as a method to optimize freeway safety ...

Air-launched GPR evaluation for rapid assessment of MoDOT bridge decks.

DOT National Transportation Integrated Search

2014-08-01

The overarching goal of this study is to demonstrate that advanced nondestructive testing/evaluation (NDT/NDE) techniques can be rapidly, effectively, and economically implemented as part of routine MoDOT bridge deck surveys to determine the general ...

Highly biocompatible yogurt-derived carbon dots as multipurpose sensors for detection of formic acid vapor and metal ions

NASA Astrophysics Data System (ADS)

Moonrinta, Sasaluck; Kwon, Binhee; In, Insik; Kladsomboon, Sumana; Sajomsang, Warayuth; Paoprasert, Peerasak

2018-07-01

Carbon dots are fascinating nanomaterials given their straightforward synthesis, unique optical properties, sensing capabilities, and biocompatibility. In this work, biocompatible carbon dots were prepared from yogurt using a two-step pyrolysis/hydrothermal method. The dots were spherical in shape with an average size of 4.7 nm. They showed blue emission under UV illumination with a quantum yield of 1.5%. Their photoluminescence was stable over three months and in both strong buffer solutions and highly concentrated salt solutions. The optical absorption and photoluminescence properties of the dots were employed for vapor and metal ion sensing, respectively. For the first time, the carbon dots were integrated into an optical electronic nose, and used for the detection of formic acid vapor at room temperature. Sensing was based on monitoring the optical transmission through a carbon dot film upon exposure to vapor, and the results were confirmed by UV-visible spectroscopy. The carbon dot-integrated electronic nose was able to distinguish vapor from formic acid/water solutions at different concentrations, with a detection limit of 7.3% v/v. The sensitivity of the dots to metal ions was tested by measuring the photoluminescence emission intensity at different excitation wavelengths. Principal component analysis was used to differentiate between the ions. The results suggested that interactions between carbon dots and metals ions occurred at a range of binding sites. The biocompability of the dots was demonstrated to be excellent. The study identified carbon dots produced from yogurt as multipurpose fluorescent nanomaterials with potential sensing and biomedical applications.

pH-responsive drug release and real-time fluorescence detection of porous silica nanoparticles.

PubMed

Zhang, Xu; Wang, Yamin; Zhao, Yanbao; Sun, Lei

2017-08-01

In this work, pH-sensitive "dual-switch" porous silica (pSiO 2 ) nanoparticles (NPs) were constructed for drug delivery. Poly(acrylic acid) (PAA) was grafting onto the internal and external surfaces of amino groups functionalized porous silica (pSiO 2 -NH 2 ) NPs by the amidation between the amino groups and the carboxyl groups of PAA for pH triggered drug release. The resultant pSiO 2 /PAA NPs have an average diameter of 50-60nm and high specific surface area (914m 2 ·g -1 ). To improve the loading capacity, ZnO quantum dots (QDs) were used to block the partial pores of pSiO 2 /PAA and the loading capacity reached to 28% for methotrexate (MTX) model drug. The in vitro cellular cytotoxicity test and a hemolysis assay demonstrated that the pSiO 2 /PAA/ZnO NPs were highly biocompatible and suitable to utilize as drug carriers. The MTX-loaded pSiO 2 /PAA/ZnO NPs displayed more efficient cytotoxic to HepG2 cells than free MTX. The pSiO 2 /PAA/ZnO NPs displayed low premature, pH-responsive release and pH-dependent fluorescence. Moreover, pH-dependent fluorescence enables to trace MTX release behavior. Copyright © 2017 Elsevier B.V. All rights reserved.

Inorganic Nanomaterials as Carriers for Drug Delivery.

PubMed

Chen, Shizhu; Hao, Xiaohong; Liang, Xingjie; Zhang, Qun; Zhang, Cuimiao; Zhou, Guoqiang; Shen, Shigang; Jia, Guang; Zhang, Jinchao

2016-01-01

For safe and effective therapy, drugs must be delivered efficiently and with minimal systemic side effects. Nanostructured drug carriers enable the delivery of small-molecule drugs as well as nucleic acids and proteins. Inorganic nanomaterials are ideal for drug delivery platforms due to their unique physicochemical properties, such as facile preparation, good storage stability and biocompatibility. Many inorganic nanostructure-based drug delivery platforms have been prepared. Although there are still many obstacles to overcome, significant advances have been made in recent years. This review focuses on the status and development of inorganic nanostructures, including silica, quantum dots, gold, carbon-based and magnetic iron oxide-based nanostructures, as carriers for chemical and biological drugs. We specifically highlight the extensive use of these inorganic drug carriers for cancer therapy. Finally, we discuss the most important areas in the field that urgently require further study.

Convective and Diffusive O2 Transport Components of Peak Oxygen Uptake Following Long-duration Spaceflight

NASA Technical Reports Server (NTRS)

Ade, Carl J.; Moore, A. D.

2014-01-01

Spaceflight reduces aerobic capacity and may be linked with maladaptations in the O2 transport pathway. The aim was to 1) evaluate the cardiorespiratory adaptations following 6 months aboard the International Space Station and 2) model the contributions of convective (Q (raised dot) O2) and peripheral diffusive (DO2) components of O2 transport to changes in peak O2 uptake (V (raised dot) O2PEAK). To date, 1 male astronaut (XX yrs) completed an incremental exercise test to measure V (raised dot) O2PEAK prior to and 2 days post-flight. Cardiac output (Q (raised dot) ) was measured at three submaximal work rates via carbon dioxide rebreathing. The Q (raised dot) :V (raised dot) O2 relationship was extrapolated to V (raised dot) O2PEAK to determine Q (raised dot) PEAK. Hemoglobin concentration was measured at rest via a venous blood sample. These measurements were used to model the changes in Q (raised dot) O2 and DO2 using Fick's principle of mass conservation and Law of Diffusion as established by Wagner and colleagues (Annu. Rev. Physiol 58: 21-50, 1996 and J. Appl. Physiol. 73: 1067-1076, 1992). V (raised dot) O2PEAK decreased postflight from 3.72 to 3.45 l min-1, but Q (raised dot) PEAK increased from 24.5 to 27.7 l min-1. The decrease in V (raised dot) O2PEAK post-flight was associated with a 21.2% decrease in DO2, an 18.6% decrease in O2 extraction, but a 3.4% increase in Q (raised dot) O2. These preliminary data suggest that long-duration spaceflight reduces peripheral diffusing capacity and that it largely contributes to the post-flight decrease in aerobic capacity.

Rapid fabrication of carbon quantum dots as multifunctional nanovehicles for dual-modal targeted imaging and chemotherapy.

PubMed

Chiu, Sheng-Hui; Gedda, Gangaraju; Girma, Wubshet Mekonnen; Chen, Jem-Kun; Ling, Yong-Chien; Ghule, Anil V; Ou, Keng-Liang; Chang, Jia-Yaw

2016-12-01

Herein, we synthesized an S, N, and Gd tri-element doped magnetofluorescent carbon quantum dots (GdNS@CQDs) within 10min by using a one-pot microwave method. Our results showed that these magnetofluorescent GdNS@CQDs have excellent fluorescent and magnetic properties. Moreover, GdNS@CQDs exhibited high stability at physiological conditions and ionic strength. These magnetofluorescent GdNS@CQDs were conjugated with a folic acid, denoted as FA-GdNS@CQDs, for targeting dual modal fluorescence/magnetic resonance (MR) imaging. The in vitro and in vivo studies confirmed the high biocompatibility and low toxicity of FA-GdNS@CQDs. FA-GdNS@CQDs enhanced the MR response as compared to that for commercial Gd-DTPA. The targeting capabilities of FA-GdNS@CQDs were confirmed in HeLa and HepG2 cells using in vitro fluorescence and MR dual modality imaging. Additionally, an anticancer drug, doxorubicin, was incorporated into the FA-GdNS@CQDs forming FA-GdNS@CQDs-DOX, which enables targeted drug delivery. Importantly, the prepared FA-GdNS@CQDs-DOX showed a high quantity of doxorubicin loading capacity (about 80%) and pH-sensitive drug release. The uptake into cancer cells and the intracellular location of the FA-GdNS@CQDs were observed by confocal laser scanning microscopy. We also successfully demonstrated in vivo fluorescence bio imaging of the FA-GdNS@CQDs, using zebrafish as an animal model. In this manuscript, we reported a facial, rapid, and environmental friendly method to fabricate hetero atoms including gadolinium, nitrogen, and sulfur doped multi-functional magnetofluorescent carbon quantum dots (GdNS@CQDs) nanocomposite. These multifunctional GdNS@CQDs were conjugated with a folic acid for targeting dual modal fluorescence/magnetic resonance imaging. Additionally, an anticancer drug, doxorubicin, was incorporated into the nanocomposite forming FA-GdNS@CQDs-DOX, which enables targeted drug delivery. We have developed GdNS@CQDs with integrated functions for simultaneous in vitro cell imaging, targeting, and pH-sensitive controlled drug release in HeLa cells. Furthermore, we successfully demonstrated the use of this material for in vivo fluorescence imaging, using zebrafish as an animal model. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

EDITORIAL: Nanotechnology in vivo Nanotechnology in vivo

NASA Astrophysics Data System (ADS)

Demming, Anna

2010-04-01

Since the development of x-rays the ability to image inside our bodies has provided medicine with a potent diagnostic tool, as well as fascinating us with the eerie evidence of our mechanistic mortality. In December 2008 Osamu Shimomura, Martin Chalfie and Roger Y Tsien received a Nobel Prize for the discovery and development of the green fluorescent protein. The award recognised a new discovery that further facilitated our abilities to follow cellular activities and delve deeper into the workings of living organisms. Since the first observation of green fluorescent protein in jelly fish over thirty years ago, quantum dots have emerged as a potential alternative tool for imaging [1]. The advantages of quantum dots over organic dyes and fluorescent proteins include intense luminescence, high molar extinction coefficient, resistance to photobleaching, and broad excitation with narrow emission bands. However, one drawback for biological applications has been the layer of hydrophobic organic ligands often present at the surface as a result of the synthesis procedures. One solution to improve the solubility of quantum dots has been to conjugate them with a hydrophilic substance, as reported by Nie et al [2]. Chitosan is a hydrophilic, non-toxic, biocompatible and biodegradable substance and has been conjugated with quantum dots such as CdSe-ZnS [2] for bioassays and intracellular labelling. As well as luminescence, different nanoparticles present a variety of exceptional properties that render them useful in a range of bio applications, including MRI, drug delivery and cancer hyperthermia therapy. The ability to harness these various attributes in one system was reported by researchers in China, who incorporated magnetic nanoparticles, fluorescent quantum dots and pharmaceutical drugs into chitosan nanoparticles for multifunctional smart drug delivery systems [3]. More recently silicon quantum dots have emerged as a less cytotoxic alternative to CdSe for bio-imaging labels [4]. A surface hydroxyl group renders silicon quantum dots soluble in water and the photoluminescence can be made stable with oxygen-passivation. In addition, researchers in Japan have demonstrated how the initially modest yield in the preparation of silicon quantum dots can be improved to tens of milligrams per batch, thus further promoting their application in bio-imaging [5]. In the search for non-toxic quantum dots, researchers at the Amrita Centre for Nanoscience in India have prepared heavy metal-free quantum dot bio-probes based on single phase ZnS [6]. The quantum dots are selectively doped with metals, transition metals and halides to provide tuneable luminescence properties, and they are surface conjugated with folic acid for cancer targeting. The quantum dots were demonstrated to be water-soluble, non-toxic in normal and cancer cell lines, and have bright, tuneable luminescence. So far most of the quantum dots developed for bio-imaging have had excitation and emission wavelengths in the visible spectrum, which is highly absorbed by tissue. This limits imaging with these quantum dots to superficial tissues. This week, researchers in China and the US reported work developing functionalized dots for in vivo tumour vasculature in the infrared part of the spectrum [7]. In addition the quantum dots were functionalised with glycine-aspartic acid (RGD) peptides, which target the vasculature of almost all types of growing tumours, unlike antibody- or aptamer-mediated targeting strategies that are specific to a particular cancer type. In this issue, researchers in China and the US demonstrate a novel type of contrast agent for ultrasonic tumour imaging [8]. Contrast-enhanced ultrasonic tumour imaging extends the diagnostic and imaging capabilities of traditional techniques. The use of nanoparticles as ultrasound contrast agents exploits the presence of open pores in the range of 380 to 780 nm in tumour blood vessels, which enhance the permeability and retention of nanoparticles in the tumour vasculature. However, previous reports on techniques to generate nanobubbles have either been slow or problematic due to the resulting development of cardiac dimension reduction, hypotension and tachycardia. Xing and colleagues have now demonstrated the use of polyoxyethylene 40 stearate, which is known to be biocompatible, degradable and non-toxic, as an alternative surfactant for generating nanobubbles. In the early 1980s scanning probe micrographs of nanosized features unleashed the power of imaging to push forward the science of structures and mechanisms at the nanoscale. The continued development of new and increasingly sophisticated nanoparticles and systems looks set to empower medicine in the same way, providing further means to exploit the mechanistic nature of biological organisms for better health and longevity. References [1] Leon R, Petroff P M, Leonard D and Fafard S 1995 Science 267 1966-8 [2] Nie Q, Tan W B and Zhang Y 2006 Nanotechnology 17 140-4 [3] Li L, Chen D, Zhang Y, Deng Z, Ren X, Meng X, Tang F, Ren J and Zhang L 2007 Nanotechnology 18 405102 [4] Fujioka K et al 2008 Nanotechnology 19 415102 [5] Shinoda K, Yangisawa S, Sato K amd Hirakuri K 2006 J. Cryst. Growth 288 84-6 [6] Manzoor K, Johny S, Thomas D, Setua S, Menon D and Nair S 2009 Nanotechnology 20 065102 [7] Hu R, Yong K-T, Roy I, Ding H, Law W-C, Cai H, Zhang X, Vathy L A, Bergey E J and Prasad P N 2010 Nanotechnology 21 145105 [8] Xing, Z, Ke H, Wang J, Zhao B, Yue X, Dai Z and Liu J 2010 Nanotechnology 21 145607

Carboxymethyl chitosan based nanocomposites containing chemically bonded quantum dots and magnetic nanoparticles

NASA Astrophysics Data System (ADS)

Ding, Yongling; Yin, Hong; Chen, Rui; Bai, Ru; Chen, Chunying; Hao, Xiaojuan; Shen, Shirley; Sun, Kangning; Liu, Futian

2018-03-01

A biocompatible nanocomposite consisting of fluorescent quantum dots (QDs) and magnetic nanoparticles (MNPs) has been constructed via carboxymethyl chitosan (CMCS), resulting in magnetic-fluorescent nanoparticles (MFNPs). In these MFNPs, QDs and MNPs are successfully conjugated via covalent bonds onto the surface of CMCS. The composite retains favorable magnetic and fluorescent properties and shows a good colloidal stability in physiological environments. Folate (FA) as a specific targeting ligand was further incorporated into the nanocomposites to form a delivery vehicle with a targeting function. The therapeutic activity was achieved by loading chemotherapeutic drug doxorubicin (DOX) through electrostatic and hydrophobic interactions. The cumulative DOX release profile shows pH-sensitive. Both flow cytometry analysis and confocal laser scanning microscopic observation suggested that these nanocomposites were uptaken by cancer cells via FA receptor-mediated endocytosis pathway. In summary, the CMCS based nanocomposites developed in this work have a great potential for effective cancer-targeting and drug delivery, as well as in situ cellular imaging.

Highly efficient multifunctional MnSe/ZnSeS quantum dots for biomedical applications

NASA Astrophysics Data System (ADS)

Armijo, Leisha M.; Akins, Brian A.; Plumley, John B.; Rivera, Antonio C.; Withers, Nathan J.; Cook, Nathaniel C.; Smolyakov, Gennady A.; Huber, Dale L.; Smyth, Hugh D. C.; Osińki, Marek

2013-03-01

Colloidal quantum dots (QDs) are of interest for a variety of biomedical applications, including bioimaging, drug targeting, and photodynamic therapy. However, a significant limitation is that highly efficient photoluminescent QDs available commercially contain cadmium. Recent research has focused on cadmium-free QDs, which are anticipated to exhibit significantly lower cytotoxicity. Previous work has focused on InP and ZnO as alternative semiconductor materials for QDs. However, these nanoparticles have been shown to be cytotoxic. Recently, we have synthesized high quantum efficiency (exceeding 90%), color tunable MnSe/ZnSeS nanoparticles, as potentially attractive QDs for biomedical applications. Additionally, the manganese imparts magnetic properties on the QDs, which are important for magnetic field-guided transport, hyperthermia, and potentially magnetic resonance imaging (MRI). The QDs can be further biofunctionalized via conjugation to a ligand or a biomarker of disease, allowing combination of drug delivery with visual verification and colocalization due to the color tunability of the QDs.

Advances in Testing Techniques for Digital Microfluidic Biochips

PubMed Central

Shukla, Vineeta; Hussin, Fawnizu Azmadi; Hamid, Nor Hisham; Zain Ali, Noohul Basheer

2017-01-01

With the advancement of digital microfluidics technology, applications such as on-chip DNA analysis, point of care diagnosis and automated drug discovery are common nowadays. The use of Digital Microfluidics Biochips (DMFBs) in disease assessment and recognition of target molecules had become popular during the past few years. The reliability of these DMFBs is crucial when they are used in various medical applications. Errors found in these biochips are mainly due to the defects developed during droplet manipulation, chip degradation and inaccuracies in the bio-assay experiments. The recently proposed Micro-electrode-dot Array (MEDA)-based DMFBs involve both fluidic and electronic domains in the micro-electrode cell. Thus, the testing techniques for these biochips should be revised in order to ensure proper functionality. This paper describes recent advances in the testing technologies for digital microfluidics biochips, which would serve as a useful platform for developing revised/new testing techniques for MEDA-based biochips. Therefore, the relevancy of these techniques with respect to testing of MEDA-based biochips is analyzed in order to exploit the full potential of these biochips. PMID:28749411

Advances in Testing Techniques for Digital Microfluidic Biochips.

PubMed

Shukla, Vineeta; Hussin, Fawnizu Azmadi; Hamid, Nor Hisham; Zain Ali, Noohul Basheer

2017-07-27

With the advancement of digital microfluidics technology, applications such as on-chip DNA analysis, point of care diagnosis and automated drug discovery are common nowadays. The use of Digital Microfluidics Biochips (DMFBs) in disease assessment and recognition of target molecules had become popular during the past few years. The reliability of these DMFBs is crucial when they are used in various medical applications. Errors found in these biochips are mainly due to the defects developed during droplet manipulation, chip degradation and inaccuracies in the bio-assay experiments. The recently proposed Micro-electrode-dot Array (MEDA)-based DMFBs involve both fluidic and electronic domains in the micro-electrode cell. Thus, the testing techniques for these biochips should be revised in order to ensure proper functionality. This paper describes recent advances in the testing technologies for digital microfluidics biochips, which would serve as a useful platform for developing revised/new testing techniques for MEDA-based biochips. Therefore, the relevancy of these techniques with respect to testing of MEDA-based biochips is analyzed in order to exploit the full potential of these biochips.

2007 Precision Strike PEO Summer Forum - Joint Perspectives on Precision Engagement

DTIC Science & Technology

2007-07-11

Status,” Colonel Richard Justice, USAF—Commander of the Miniature Munitions Systems Group (MMSG), Eglin Air Force Base “Unmanned Systems (UAS) Roadmap...Role in the Roadmap Implementation Methods & Processes Working Group Issues delineated in Implementation Plan form basis for JTEM methodology...Test and Evaluation JMETC – Joint Mission Environment Test Capability WG – Working Group DOT&E AT&L DOT&E Unclassified 5 Background: JTEM Problem

Test report dot7A type A liquid packaging

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

Ketusky, E. T.; Brandjes, C.; Benoit, T. J.

2017-09-19

This section presents a general description of the DOT Specification 7A Type A liquid content packaging (HVYTAL), the liquid content evaluated as its payload, acceptable payload shipping configurations and features special to its use. This test report documents compliance with the regulatory safety requirements of 49 CFR Parts 173.24, 173.24a, 173.27, 173.410, 173.412, 173.461 – 173.466 and 178.350.

Micro Dot Patterning on the Light Guide Panel Using Powder Blasting

PubMed Central

Jang, Ho Su; Cho, Myeong Woo; Park, Dong Sam

2008-01-01

This study is to develop a micromachining technology for a light guide panel(LGP) mold, whereby micro dot patterns are formed on a LGP surface by a single injection process instead of existing screen printing processes. The micro powder blasting technique is applied to form micro dot patterns on the LGP mold surface. The optimal conditions for masking, laminating, exposure, and developing processes to form the micro dot patterns are first experimentally investigated. A LGP mold with masked micro patterns is then machined using the micro powder blasting method and the machinability of the micro dot patterns is verified. A prototype LGP is test- injected using the developed LGP mold and a shape analysis of the patterns and performance testing of the injected LGP are carried out. As an additional approach, matte finishing, a special surface treatment method, is applied to the mold surface to improve the light diffusion characteristics, uniformity and brightness of the LGP. The results of this study show that the applied powder blasting method can be successfully used to manufacture LGPs with micro patterns by just single injection using the developed mold and thereby replace existing screen printing methods. PMID:27879740

Crash testing and evaluation of TxDOT burn ban signs.

DOT National Transportation Integrated Search

2009-08-01

Texas counties expressed a desire to the Texas Department of Transportation (TxDOT) to post : advisory signs on the roadside to alert motorists when a burn ban is in effect. For obvious economic reasons, : the preferred method of implementation is to...

Driver behavior analysis at highway-rail grade crossings using field operational test data - light vehicles

DOT National Transportation Integrated Search

2013-05-31

The U. S. Department of Transportations (U.S. DOT) Research and Innovative Technology Administrations (RITA) John A. Volpe National Transportation Systems Center (Volpe Center), under the direction of the U.S. DOT Federal Railroad Administratio...

Driver behavior analysis at highway-rail grade crossings using field operational test data - heavy trucks

DOT National Transportation Integrated Search

2012-12-31

The United States Department of Transportations (U.S. DOT) Research and Innovative Technology Administrations (RITA) John A. Volpe National Transportation Systems Center (Volpe Center), under the direction of the U.S. DOT Federal Railroad Admin...

MINIMAL HEPATIC ENCEPHALOPATHY IS ASSOCIATED WITH MOTOR VEHICLE CRASHES: THE REALITY BEYOND THE DRIVING TEST

PubMed Central

Bajaj, Jasmohan S; Saeian, Kia; Schubert, Christine M; Hafeezullah, Muhammad; Franco, Jose; Varma, Rajiv R; Gibson, Douglas P; Hoffmann, Raymond G; Stravitz, R Todd; Heuman, Douglas M; Sterling, Richard K; Shiffman, Mitchell; Topaz, Allyne; Boyett, Sherry; Bell, Debulon; Sanyal, Arun J

2009-01-01

Patients with minimal hepatic encephalopathy (MHE) have impaired driving skills, but association of MHE with motor vehicle crashes is unclear. Standard psychometric tests (SPT) or inhibitory control test (ICT) can be used to diagnose MHE. The aim was to determine the association of MHE with crashes and traffic violations over the preceding year and on 1-year follow-up. Cirrhotics were diagnosed with MHE by ICT (MHEICT) and SPT (MHESPT). Self and department-of-transportation (DOT)-reports were used to determine crashes and violations over the preceding year. Agreement between self and DOT-reports was analyzed. Patients then underwent 1 year follow-up for crash/violation occurrence. Crashes in those with/without MHEICT and MHESPT were compared. 167 cirrhotics had DOT-reports, of which 120 also had self-reports. A significantly higher proportion of MHEICT cirrhotics experienced crashes in the preceding year compared to those without MHE by self-report (17% vs. 0%, p=0.0004) and DOT-reports (17% vs. 3%, p=0.004, relative risk:5.77). SPT did not differentiate between those with/without crashes. A significantly higher proportion of patients with crashes had MHEICT compared to MHESPT, both self-reported (100% vs. 50%, p=0.03) and DOT-reported (89% vs. 44%, p=0.01). There was excellent agreement between self and DOT-reports for crashes and violations (Kappa 0.90 and 0.80). 109 patients were followed prospectively. MHEICT patients had a significantly higher future crashes/violations compared to those without (22% vs. 7%, p=0.03) but MHESPT did not. MHEICT (Odds ratio:4.51) and prior year crash/violation (Odds ratio:2.96) were significantly associated with future crash/violation occurrence. PMID:19670416

Facial recognition using simulated prosthetic pixelized vision.

PubMed

Thompson, Robert W; Barnett, G David; Humayun, Mark S; Dagnelie, Gislin

2003-11-01

To evaluate a model of simulated pixelized prosthetic vision using noncontiguous circular phosphenes, to test the effects of phosphene and grid parameters on facial recognition. A video headset was used to view a reference set of four faces, followed by a partially averted image of one of those faces viewed through a square pixelizing grid that contained 10x10 to 32x32 dots separated by gaps. The grid size, dot size, gap width, dot dropout rate, and gray-scale resolution were varied separately about a standard test condition, for a total of 16 conditions. All tests were first performed at 99% contrast and then repeated at 12.5% contrast. Discrimination speed and performance were influenced by all stimulus parameters. The subjects achieved highly significant facial recognition accuracy for all high-contrast tests except for grids with 70% random dot dropout and two gray levels. In low-contrast tests, significant facial recognition accuracy was achieved for all but the most adverse grid parameters: total grid area less than 17% of the target image, 70% dropout, four or fewer gray levels, and a gap of 40.5 arcmin. For difficult test conditions, a pronounced learning effect was noticed during high-contrast trials, and a more subtle practice effect on timing was evident during subsequent low-contrast trials. These findings suggest that reliable face recognition with crude pixelized grids can be learned and may be possible, even with a crude visual prosthesis.

Biomass-based magnetic fluorescent nanoparticles: One-step scalable synthesis, application as drug carriers and mechanism study.

PubMed

Li, Lei; Wang, Feijun; Shao, Ziqiang

2018-03-15

A biomass-based magnetic fluorescent nanoparticle (MFNPs) was successively in situ synthesized via a one-step high-gravity approach, which constructed by a magnetic core of Fe 3 O 4 nanoparticles, the fluorescent marker of carbon dots (CDs), and shells of chitosan (CS). The obtained MFNPs had a 10 nm average diameter and narrow particle size distribution, low cytotoxicity, superior fluorescent emission and superparamagnetic properties. The encapsulating and release 5-fluorouracil experiments confirmed that the introduction of CS/CDs effectively improved the drug loading capacity. Mechanism and kinetic studies proved that: (i) the monolayer adsorption was the main sorption mode under the studied conditions; (ii) the whole adsorption process was controlled by intra-liquid diffusion mass transfer and governed by chemisorption; and (iii) the release process was controlled by Fickian diffusion. These results demonstrated this method to one-step continuously produce MFNPs and the construction of non-toxic nanostructure possessed great superiority in currently Nano-delivery systems, which would show high application value in targeted drug delivery, magnetic fluid hyperthermia treatment, magnetic resonance imaging (MRI), in vitro testing and relative research. Copyright © 2017 Elsevier Ltd. All rights reserved.

Risk Factors for DOTS Treatment Default Among New HIV-TB Coinfected Patients in Nalgonda (Dist.) Telangana (State): A Case Control Study.

PubMed

Reddy Satti, Siva Balaji; Kondagunta, Nagaraj

2016-01-01

The therapeutic regimens as recommended by the Revised National TB Control Programme (RNTCP) have been shown to be highly effective for both preventing and treating tuberculosis, but poor adherence to medication is a major barrier to its global control. The study was conducted to assess the influence of patient related factors for DOTS Treatment Default among HIV-TB Co-infected cases. This was a case control study conducted in Nalgond, Telangana. All new HIV-TB coinfected and DOTS-defaulted patients registered under RNTCP for the period from January 2010 to December 2012 were selected. Of the 154 patients, 23 had died and 11 could not be traced, and these were excluded. Thus the total number of available cases were 120 for those age- and sex-matched controls (HIV-TB coinfected patients and those who had completed the DOTS regimen successfully) were selected. The mean age was 36.5 ± 9 years; the majority (23.3%) of patients defaulted during the second month of treatment. Significant risk factors associated with defaulting included unskilled occupation [adjusted odds ratio (AOR: 3.56; 95% confidence interval (CI): 1.1-11.56], lower middle class socioeconomic status (AOR: 17.16; 95% CI: 3.93-74.82), small family size (AOR: 21.3; 95% CI: 6.4-70.91), marital disharmony (AOR: 6.78; 95% CI: 1.93-23.76), not being satisfied with the conduct of health personnel (AOR: 7.38; 95% CI: 2.32-23.39), smoking (AOR: 8.5; 95% CI: 2.31-31.21), and side effects of drugs (AOR: 4.18; 95% CI: 1.35-12.9). Unskilled occupation, marital disharmony, small family size, lower middle class socioeconomic status, not being satisfied with the conduct of health personnel, smoking, and drug side effects were significantly associated with defaulting. Information on the pattern of tuberculosis (TB), the outcome of anti-tuberculosis treatment (ATT), and the factors associated with it will help in planning interventions to improve adherence to DOTS treatment.

Cost-effectiveness of meglumine antimoniate versus miltefosine caregiver DOT for the treatment of pediatric cutaneous leishmaniasis

PubMed Central

Cossio, Alexandra; Saravia, Nancy Gore; Castro, Maria del Mar; Prada, Sergio; Bartlett, Allison H.; Pho, Mai T.

2017-01-01

Background Oral miltefosine has been shown to be non-inferior to first-line, injectable meglumine antimoniate (MA) for the treatment of cutaneous leishmaniasis (CL) in children. Miltefosine may be administered via in-home caregiver Directly Observed Therapy (cDOT), while patients must travel to clinics to receive MA. We performed a cost-effectiveness analysis comparing miltefosine by cDOT versus MA for pediatric CL in southwest Colombia. Methodology/Principle findings We developed a Monte Carlo model comparing the cost-per-cure of miltefosine by cDOT compared to MA from patient, government payer, and societal perspectives (societal = sum of patient and government payer perspective costs). Drug effectiveness and adverse events were estimated from clinical trials. Healthcare utilization and costs of travel were obtained from surveys of providers and published sources. The primary outcome was cost-per-cure reported in 2015 USD. Treatment efficacy, costs, and adherence were varied in sensitivity analysis to assess robustness of results. Treatment with miltefosine resulted in substantially lower cost-per-cure from a societal and patient perspective, and slightly higher cost-per-cure from a government payer perspective compared to MA. Mean societal cost-per-cure were $531 (SD±$239) for MA and $188 (SD±$100) for miltefosine, a mean cost-per-cure difference of +$343. Mean cost-per-cure from a patient perspective were $442 (SD ±$233) for MA and $30 (SD±$16) for miltefosine, a mean difference of +$412. Mean cost-per-cure from a government perspective were $89 (SD±$55) for MA and $158 (SD±$98) for miltefosine, with a mean difference of -$69. Results were robust across a variety of assumptions in univariate and multi-way analysis. Conclusions/Significance Treatment of pediatric cutaneous leishmaniasis with miltefosine via cDOT is cost saving from patient and societal perspectives, and moderately more costly from the government payer perspective compared to treatment with MA. Results were robust over a range of sensitivity analyses. Lower drug price for miltefosine could result in cost saving from a government perspective. PMID:28384261

Functional sensibility of the hand in leprosy patients.

PubMed

van Brakel, W H; Kets, C M; van Leerdam, M E; Khawas, I B; Gurung, K S

1997-03-01

The aims of this cross-sectional comparative study was to compare the results of Semmes-Weinstein monofilament testing (SWM) and moving 2-point discrimination (M2PD) with four tests of functional sensibility: recognition of objects, discrimination of size and texture and detection of dots. Ninety-eight leprosy in- and outpatients at Green Pastures Hospital in Pokhara, Nepal were tested with each of the above tests and the results were compared to see how well they agreed. Using the tests of functional sensibility as reference points, we examined the validity of the SWM and M2PD as predictors of functional sensibility. There was definite, but only moderate correlation between thresholds of monofilaments and M2PD and functional sensibility of the hand. A normal result with the SWM and/or M2PD had a good predictive value for normal functional sensibility. Sensitivity was reasonable against recognition of objects and discrimination of textures as reference tests (80-90% and 88-93%), but poor against discrimination of size and detection of dots (50-75% and 43-65%). Specificity was high for most combinations of SWM or M2PD with any of the tests of functional sensibility (85-99%). Above a monofilament threshold of 2 g, the predictive value of an abnormal test was 100% for dot detection and 83-92% for textural discrimination. This indicates that impairment of touch sensibility at this level correlates well with loss of dot detection and textural discrimination in patients with leprous neuropathy. For M2PD the pattern was very similar. Above a threshold of 5 mm, 95-100% of affected hands had loss of dot detection and 73-80% had loss of textural discrimination. Monofilament testing and M2PD did not seem suitable as proxy measures of functional sensibility of the hand in leprosy patients. However, a normal threshold with monofilaments and/or M2PD had a good predictive value for normal functional sensibility. Above a monofilament threshold of 2 g and/or a M2PD threshold of 5 mm, textural discrimination was abnormal in most hands.

49 CFR 40.293 - What is the SAP's function in conducting the initial evaluation of an employee?

Code of Federal Regulations, 2013 CFR

2013-10-01

... violation of a DOT drug or alcohol regulation (e.g., related to assertions of use of hemp oil, “medical marijuana” use, “contact positives,” poppy seed ingestion, job stress); or (3) Personal opinions you may...

49 CFR 40.293 - What is the SAP's function in conducting the initial evaluation of an employee?

Code of Federal Regulations, 2014 CFR

2014-10-01

... violation of a DOT drug or alcohol regulation (e.g., related to assertions of use of hemp oil, “medical marijuana” use, “contact positives,” poppy seed ingestion, job stress); or (3) Personal opinions you may...

49 CFR 40.293 - What is the SAP's function in conducting the initial evaluation of an employee?

Code of Federal Regulations, 2011 CFR

2011-10-01

... violation of a DOT drug or alcohol regulation (e.g., related to assertions of use of hemp oil, “medical marijuana” use, “contact positives,” poppy seed ingestion, job stress); or (3) Personal opinions you may...

49 CFR 40.293 - What is the SAP's function in conducting the initial evaluation of an employee?

Code of Federal Regulations, 2012 CFR

2012-10-01

... violation of a DOT drug or alcohol regulation (e.g., related to assertions of use of hemp oil, “medical marijuana” use, “contact positives,” poppy seed ingestion, job stress); or (3) Personal opinions you may...

Polydiacetylene-enclosed near-infrared fluorescent semiconducting polymer dots for bioimaging and sensing.

PubMed

Wu, Pei-Jing; Kuo, Shih-Yu; Huang, Ya-Chi; Chen, Chuan-Pin; Chan, Yang-Hsiang

2014-05-20

Semiconducting polymer dots (P-dots) recently have emerged as a new type of ultrabright fluorescent probe with promising applications in biological imaging and detection. With the increasing desire for near-infrared (NIR) fluorescing probes for in vivo biological measurements, the currently available NIR-emitting P-dots are very limited and the leaching of the encapsulated dyes/polymers has usually been a concern. To address this challenge, we first embedded the NIR dyes into the matrix of poly[(9,9-dioctylfluorene)-co-2,1,3-benzothiadiazole-co-4,7-di(thiophen-2-yl)-2,1,3-benzothiadiazole] (PF-BT-DBT) polymer and then enclosed the doped P-dots with polydiacetylenes (PDAs) to avoid potential leakage of the entrapped NIR dyes from the P-dot matrix. These PDA-enclosed NIR-emitting P-dots not only emitted much stronger NIR fluorescence than conventional organic molecules but also exhibited enhanced photostability over CdTe quantum dots, free NIR dyes, and gold nanoclusters. We next conjugated biomolecules onto the surface of the resulting P-dots and demonstrated their capability for specific cellular labeling without any noticeable nonspecific binding. To employ this new class of material as a facile sensing platform, an easy-to-prepare test paper, obtained by soaking the paper into the PDA-enclosed NIR-emitting P-dot solution, was used to sense external stimuli such as ions, temperature, or pH, depending on the surface functionalization of PDAs. We believe these PDA-coated NIR-fluorescing P-dots will be very useful in a variety of bioimaging and analytical applications.

A new analytical method for estimating lumped parameter constants of linear viscoelastic models from strain rate tests

NASA Astrophysics Data System (ADS)

Mattei, G.; Ahluwalia, A.

2018-04-01

We introduce a new function, the apparent elastic modulus strain-rate spectrum, E_{app} ( \\dot{ɛ} ), for the derivation of lumped parameter constants for Generalized Maxwell (GM) linear viscoelastic models from stress-strain data obtained at various compressive strain rates ( \\dot{ɛ}). The E_{app} ( \\dot{ɛ} ) function was derived using the tangent modulus function obtained from the GM model stress-strain response to a constant \\dot{ɛ} input. Material viscoelastic parameters can be rapidly derived by fitting experimental E_{app} data obtained at different strain rates to the E_{app} ( \\dot{ɛ} ) function. This single-curve fitting returns similar viscoelastic constants as the original epsilon dot method based on a multi-curve global fitting procedure with shared parameters. Its low computational cost permits quick and robust identification of viscoelastic constants even when a large number of strain rates or replicates per strain rate are considered. This method is particularly suited for the analysis of bulk compression and nano-indentation data of soft (bio)materials.

Measuring Steady-State Oxygen Uptake during the 6-Min Walk Test in Adults with Cerebral Palsy: Feasibility and Construct Validity

ERIC Educational Resources Information Center

Maltais, Desiree B.; Robitaille, Nancy-Michelle; Dumas, Francine; Boucher, Normand; Richards, Carol L.

2012-01-01

This study evaluated the feasibility of measuring steady-state oxygen uptake (V[Combining Dot Above]O[subscript 2]) during the 6-min walk test (6MWT) in adults with cerebral palsy (CP) who walk without support and whether there is construct validity for net 6MWT V[Combining Dot Above]O[subscript 2] as a measure of their walking ability.…

A multifunctional ribonuclease A-conjugated carbon dot cluster nanosystem for synchronous cancer imaging and therapy

PubMed Central

2014-01-01

Carbon dots exhibit great potential in applications such as molecular imaging and in vivo molecular tracking. However, how to enhance fluorescence intensity of carbon dots has become a great challenge. Herein, we report for the first time a new strategy to synthesize fluorescent carbon dots (C-dots) with high quantum yields by using ribonuclease A (RNase A) as a biomolecular templating agent under microwave irradiation. The synthesized RNase A-conjugated carbon dots (RNase A@C-dots) exhibited quantum yields of 24.20%. The fluorescent color of the RNase A@C-dots can easily be adjusted by varying the microwave reaction time and microwave power. Moreover, the emission wavelength and intensity of RNase A@C-dots displayed a marked excitation wavelength-dependent character. As the excitation wavelength alters from 300 to 500 nm, the photoluminescence (PL) peak exhibits gradually redshifts from 450 to 550 nm, and the intensity reaches its maximum at an excitation wavelength of 380 nm. Its Stokes shift is about 80 nm. Notably, the PL intensity is gradually decreasing as the pH increases, almost linearly dependent, and it reaches the maximum at a pH = 2 condition; the emission peaks also show clearly a redshift, which may be caused by the high activity and perfective dispersion of RNase A in a lower pH solution. In high pH solution, RNase A tends to form RNase A warped carbon dot nanoclusters. Cell imaging confirmed that the RNase A@C-dots could enter into the cytoplasm through cell endocytosis. 3D confocal imaging and transmission electron microscopy observation confirmed partial RNase A@C-dots located inside the nucleus. MTT and real-time cell electronic sensing (RT-CES) analysis showed that the RNase A@C-dots could effectively inhibit the growth of MGC-803 cells. Intra-tumor injection test of RNase A@C-dots showed that RNase A@C-dots could be used for imaging in vivo gastric cancer cells. In conclusion, the as-prepared RNase A@C-dots are suitable for simultaneous therapy and in vivo fluorescence imaging of nude mice loaded with gastric cancer or other tumors. PMID:25177217

A multifunctional ribonuclease A-conjugated carbon dot cluster nanosystem for synchronous cancer imaging and therapy

NASA Astrophysics Data System (ADS)

Liu, Huiyang; Wang, Qin; Shen, Guangxia; Zhang, Chunlei; Li, Chao; Ji, Weihang; Wang, Chun; Cui, Daxiang

2014-08-01

Carbon dots exhibit great potential in applications such as molecular imaging and in vivo molecular tracking. However, how to enhance fluorescence intensity of carbon dots has become a great challenge. Herein, we report for the first time a new strategy to synthesize fluorescent carbon dots (C-dots) with high quantum yields by using ribonuclease A (RNase A) as a biomolecular templating agent under microwave irradiation. The synthesized RNase A-conjugated carbon dots (RNase A@C-dots) exhibited quantum yields of 24.20%. The fluorescent color of the RNase A@C-dots can easily be adjusted by varying the microwave reaction time and microwave power. Moreover, the emission wavelength and intensity of RNase A@C-dots displayed a marked excitation wavelength-dependent character. As the excitation wavelength alters from 300 to 500 nm, the photoluminescence (PL) peak exhibits gradually redshifts from 450 to 550 nm, and the intensity reaches its maximum at an excitation wavelength of 380 nm. Its Stokes shift is about 80 nm. Notably, the PL intensity is gradually decreasing as the pH increases, almost linearly dependent, and it reaches the maximum at a pH = 2 condition; the emission peaks also show clearly a redshift, which may be caused by the high activity and perfective dispersion of RNase A in a lower pH solution. In high pH solution, RNase A tends to form RNase A warped carbon dot nanoclusters. Cell imaging confirmed that the RNase A@C-dots could enter into the cytoplasm through cell endocytosis. 3D confocal imaging and transmission electron microscopy observation confirmed partial RNase A@C-dots located inside the nucleus. MTT and real-time cell electronic sensing (RT-CES) analysis showed that the RNase A@C-dots could effectively inhibit the growth of MGC-803 cells. Intra-tumor injection test of RNase A@C-dots showed that RNase A@C-dots could be used for imaging in vivo gastric cancer cells. In conclusion, the as-prepared RNase A@C-dots are suitable for simultaneous therapy and in vivo fluorescence imaging of nude mice loaded with gastric cancer or other tumors.

A Rapid Dot Immunoassay for the Detection of Serum Antibodies to Eastern Equine Encephalomyelitis and Saint Louis Encephalitis Viruses in Sentinel Chickens

DTIC Science & Technology

1988-01-01

tion inhibition (HI) tests .6 uses a novel membrane, polyvinylydine difluor- EEE and SLE viruses are significant public ide (PVDF), and yields a...only 3 aged values between the two tests (Fig. 3). Vari- of 6 SLE virus-inoculated birds developed an- ability in EIA titer was observed with samples... SLE samples negative by EIA were location. Four serum samples from each of 3 also negative by DotIA. EEE-positive chickens were tested by EIA and A

Analysis of Zolpidem in Postmortem Fluids and Tissues Using Ultra-Performance Liquid Chromatography-Mass Spectrometry

DTIC Science & Technology

2014-02-01

16. Abstract Zolpidem is a nonbenzodiazepine sedative hypnotic drug used for the short-term treatment of insomnia. Its use is common and wide-spread...Classif. (of this page) 21. No. of Pages 22. Price Unclassified Unclassified 15 Form DOT F 1700.7 (8-72) Reproduction of completed page authorized iii...INTRODUCTION Zolpidem is a nonbenzodiazepine sedative hypnotic drug used to treat insomnia by slowing the activity in the brain. It is prescribed as a short

Multifunctional quantum dot-polypeptide hybrid nanogel for targeted imaging and drug delivery

NASA Astrophysics Data System (ADS)

Yang, Jie; Yao, Ming-Hao; Wen, Lang; Song, Ji-Tao; Zhang, Ming-Zhen; Zhao, Yuan-Di; Liu, Bo

2014-09-01

A new type of multifunctional quantum dot (QD)-polypeptide hybrid nanogel with targeted imaging and drug delivery properties has been developed by metal-affinity driven self-assembly between artificial polypeptides and CdSe-ZnS core-shell QDs. On the surface of QDs, a tunable sandwich-like microstructure consisting of two hydrophobic layers and one hydrophilic layer between them was verified by capillary electrophoresis, transmission electron microscopy, and dynamic light scattering measurements. Hydrophobic and hydrophilic drugs can be simultaneously loaded in a QD-polypeptide nanogel. In vitro drug release of drug-loaded QD-polypeptide nanogels varies strongly with temperature, pH, and competitors. A drug-loaded QD-polypeptide nanogel with an arginine-glycine-aspartic acid (RGD) motif exhibited efficient receptor-mediated endocytosis in αvβ3 overexpressing HeLa cells but not in the control MCF-7 cells as analyzed by confocal microscopy and flow cytometry. In contrast, non-targeted QD-polypeptide nanogels revealed minimal binding and uptake in HeLa cells. Compared with the original QDs, the QD-polypeptide nanogels showed lower in vitro cytotoxicity for both HeLa cells and NIH 3T3 cells. Furthermore, the cytotoxicity of the targeted QD-polypeptide nanogel was lower for normal NIH 3T3 cells than that for HeLa cancer cells. These results demonstrate that the integration of imaging and drug delivery functions in a single QD-polypeptide nanogel has the potential for application in cancer diagnosis, imaging, and therapy.A new type of multifunctional quantum dot (QD)-polypeptide hybrid nanogel with targeted imaging and drug delivery properties has been developed by metal-affinity driven self-assembly between artificial polypeptides and CdSe-ZnS core-shell QDs. On the surface of QDs, a tunable sandwich-like microstructure consisting of two hydrophobic layers and one hydrophilic layer between them was verified by capillary electrophoresis, transmission electron microscopy, and dynamic light scattering measurements. Hydrophobic and hydrophilic drugs can be simultaneously loaded in a QD-polypeptide nanogel. In vitro drug release of drug-loaded QD-polypeptide nanogels varies strongly with temperature, pH, and competitors. A drug-loaded QD-polypeptide nanogel with an arginine-glycine-aspartic acid (RGD) motif exhibited efficient receptor-mediated endocytosis in αvβ3 overexpressing HeLa cells but not in the control MCF-7 cells as analyzed by confocal microscopy and flow cytometry. In contrast, non-targeted QD-polypeptide nanogels revealed minimal binding and uptake in HeLa cells. Compared with the original QDs, the QD-polypeptide nanogels showed lower in vitro cytotoxicity for both HeLa cells and NIH 3T3 cells. Furthermore, the cytotoxicity of the targeted QD-polypeptide nanogel was lower for normal NIH 3T3 cells than that for HeLa cancer cells. These results demonstrate that the integration of imaging and drug delivery functions in a single QD-polypeptide nanogel has the potential for application in cancer diagnosis, imaging, and therapy. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr03058c

Fourier transform spectra of quantum dots

NASA Astrophysics Data System (ADS)

Damian, V.; Ardelean, I.; Armăşelu, Anca; Apostol, D.

2009-09-01

Semiconductor quantum dots are nanometer-sized crystals with unique photochemical and photophysical properties that are not available from either isolated molecules or bulk solids. These nanocrystals absorb light over a very broad spectral range as compared to molecular fluorophores which have very narrow excitation spectra. High-quality QDs are proper to be use in different biological and medical applications (as fluorescent labels, the cancer treatment and the drug delivery). In this article, we discuss Fourier transform visible spectroscopy of commercial quantum dots. We reveal that QDs produced by Evident Technologies when are enlightened by laser or luminescent diode light provides a spectral shift of their fluorescence spectra correlated to exciting emission wavelengths, as shown by the ARCspectroNIR Fourier Transform Spectrometer. In the final part of this paper we show an important biological application of CdSe/ZnS core-shell ODs as microbial labeling both for pure cultures of cyanobacteria (Synechocystis PCC 6803) and for mixed cultures of phototrophic and heterotrophic microorganisms.

Fourier transform spectra of quantum dots

NASA Astrophysics Data System (ADS)

Damian, V.; Ardelean, I.; Armăşelu, Anca; Apostol, D.

2010-05-01

Semiconductor quantum dots are nanometer-sized crystals with unique photochemical and photophysical properties that are not available from either isolated molecules or bulk solids. These nanocrystals absorb light over a very broad spectral range as compared to molecular fluorophores which have very narrow excitation spectra. High-quality QDs are proper to be use in different biological and medical applications (as fluorescent labels, the cancer treatment and the drug delivery). In this article, we discuss Fourier transform visible spectroscopy of commercial quantum dots. We reveal that QDs produced by Evident Technologies when are enlightened by laser or luminescent diode light provides a spectral shift of their fluorescence spectra correlated to exciting emission wavelengths, as shown by the ARCspectroNIR Fourier Transform Spectrometer. In the final part of this paper we show an important biological application of CdSe/ZnS core-shell ODs as microbial labeling both for pure cultures of cyanobacteria (Synechocystis PCC 6803) and for mixed cultures of phototrophic and heterotrophic microorganisms.

Influence of Correspondence Noise and Spatial Scaling on the Upper Limit for Spatial Displacement in Fully-Coherent Random-Dot Kinematogram Stimuli

PubMed Central

Tripathy, Srimant P.; Shafiullah, Syed N.; Cox, Michael J.

2012-01-01

Correspondence noise is a major factor limiting direction discrimination performance in random-dot kinematograms [1]. In the current study we investigated the influence of correspondence noise on Dmax, which is the upper limit for the spatial displacement of the dots for which coherent motion is still perceived. Human direction discrimination performance was measured, using 2-frame kinematograms having leftward/rightward motion, over a 200-fold range of dot-densities and a four-fold range of dot displacements. From this data Dmax was estimated for the different dot densities tested. A model was proposed to evaluate the correspondence noise in the stimulus. This model summed the outputs of a set of elementary Reichardt-type local detectors that had receptive fields tiling the stimulus and were tuned to the two directions of motion in the stimulus. A key assumption of the model was that the local detectors would have the radius of their catchment areas scaled with the displacement that they were tuned to detect; the scaling factor k linking the radius to the displacement was the only free parameter in the model and a single value of k was used to fit all of the psychophysical data collected. This minimal, correspondence-noise based model was able to account for 91% of the variability in the human performance across all of the conditions tested. The results highlight the importance of correspondence noise in constraining the largest displacement that can be detected. PMID:23056172

Influence of correspondence noise and spatial scaling on the upper limit for spatial displacement in fully-coherent random-dot kinematogram stimuli.

PubMed

Tripathy, Srimant P; Shafiullah, Syed N; Cox, Michael J

2012-01-01

Correspondence noise is a major factor limiting direction discrimination performance in random-dot kinematograms. In the current study we investigated the influence of correspondence noise on Dmax, which is the upper limit for the spatial displacement of the dots for which coherent motion is still perceived. Human direction discrimination performance was measured, using 2-frame kinematograms having leftward/rightward motion, over a 200-fold range of dot-densities and a four-fold range of dot displacements. From this data Dmax was estimated for the different dot densities tested. A model was proposed to evaluate the correspondence noise in the stimulus. This model summed the outputs of a set of elementary Reichardt-type local detectors that had receptive fields tiling the stimulus and were tuned to the two directions of motion in the stimulus. A key assumption of the model was that the local detectors would have the radius of their catchment areas scaled with the displacement that they were tuned to detect; the scaling factor k linking the radius to the displacement was the only free parameter in the model and a single value of k was used to fit all of the psychophysical data collected. This minimal, correspondence-noise based model was able to account for 91% of the variability in the human performance across all of the conditions tested. The results highlight the importance of correspondence noise in constraining the largest displacement that can be detected.

Modular, Antibody-free Time-Resolved LRET Kinase Assay Enabled by Quantum Dots and Tb3+-sensitizing Peptides

NASA Astrophysics Data System (ADS)

Cui, Wei; Parker, Laurie L.

2016-07-01

Fluorescent drug screening assays are essential for tyrosine kinase inhibitor discovery. Here we demonstrate a flexible, antibody-free TR-LRET kinase assay strategy that is enabled by the combination of streptavidin-coated quantum dot (QD) acceptors and biotinylated, Tb3+ sensitizing peptide donors. By exploiting the spectral features of Tb3+ and QD, and the high binding affinity of the streptavidin-biotin interaction, we achieved multiplexed detection of kinase activity in a modular fashion without requiring additional covalent labeling of each peptide substrate. This strategy is compatible with high-throughput screening, and should be adaptable to the rapidly changing workflows and targets involved in kinase inhibitor discovery.

Synthesis and characterization of colloidal ZnTe nanocrystals and ZnTe/ZnSe quantum dots

NASA Astrophysics Data System (ADS)

Gonzales, Gavin P.; Alas, Gema; Senthil, Arjun; Withers, Nathan J.; Minetos, Christina; Sandoval, Alejandro; Ivanov, Sergei A.; Smolyakov, Gennady A.; Huber, Dale L.; Osiński, Marek

2018-02-01

Quantum dots (QDs) emitting in the visible are of interest for many biomedical applications, including bioimaging, biosensing, drug targeting, and photodynamic therapy. However, a significant limitation is that QDs typically contain cadmium, which makes prospects for their FDA approval very unlikely. Previous work has focused on InP and ZnO as alternative semiconductor materials for QDs. However, these nanoparticles have also been shown to be cytotoxic. High-efficiency luminescent ZnTe-based QDs could be a reasonable alternative to Cd-containing QDs. In this paper, we present preliminary results of our recent studies of ZnTe-based QDs, including their synthesis, structural characterization, and optical properties.

Ways and Means to Utilize Private Practitioners for Tuberculosis Care in India.

PubMed

Samal, Janmejaya

2017-02-01

The growing interest of utilizing the private practitioners in improving the outreach of public health services including Tuberculosis (TB) control programme stemmed out of people's preference for private health facilities in situations where public health facilities fail to meet the expectations. In different parts of India, many models of Public Private Partnership have been tried and tested and proved successful in providing quality TB care in the concerned community. In this paper, several ways and means have been proposed to effectively utilize private practitioners for TB care in India. These strategies are discussed under different headings: (1) identification of potential private practitioners: (2) orientation of private practitioners: (3) networking of private practitioners with patients and Directly Observed Treatment Short course (DOTS) provider: (4) follow-up and sensitization of patients by private practitioners: (5) let the word of mouth work: and (6) evaluation of the involvement of private practitioners in TB care. However the following points must be addressed before utilizing the private practitioners for TB care: time constraints in notifying the disease, adherence to DOTS regime/alternative to DOTS regime, referral of patients to public health facilities for diagnosis and treatment, follow-up and sensitization of the patients and behaviour change communication and awareness in the community by the private practitioners. Few of these are mandatory for the private practitioners; most are practicable. With the effective utilization of private practitioners many problems can be sorted out that are currently plaguing the system such as irrational and excessive use of certain drugs, over reliance on chest X-ray for diagnosis, under use of sputum microscopy, lack of knowledge regarding standard treatment protocols and varied prescription practices.

National Evaluation of the Safetrip-21 Initiative : Combined Final Report

DOT National Transportation Integrated Search

2011-03-31

Through the U.S. Department of Transportations (U.S. DOT) SafeTrip-21 Initiative, the U.S. DOT tested a variety of technologies in a number of locations in California as well as along the I-95 corridor on the east coast. This document presents the...

Human cerebral potentials evoked by moving dynamic random dot stereograms.

PubMed

Herpers, M J; Caberg, H B; Mol, J M

1981-07-01

In 11 normal healthy human subjects an evoked potential was elicited by moving dynamic random dot stereograms. The random dots were generated by a minicomputer. An average of each of 8 EEG channels of the subjects tested was made. The maximum of the cerebral evoked potentials thus found was localized in the central and parietal region. No response earlier than 130--150 msec after the stimulus could be proved. The influence of fixation, the number of dots provided, an interocular interstimulus interval in the presentation of the dots, and lense accommodation movements on the evoked stereoptic potentials was investigated and discussed. An interocular interstimulus interval (left eye leading) in the presentation of the dots caused an increase in latency of the response much longer than the imposed interstimulus interval itself. It was shown that no accommodation was needed to perceive the depth impression, and to evoke the cerebral response with random dot stereograms. There are indications of an asymmetry between the two hemispheres in the handling of depth perception after 250 msec. The potential distribution of the evoked potentials strongly suggests that they are not generated in the occipital region.

Fluorescence Determination of Warfarin Using TGA-capped CdTe Quantum Dots in Human Plasma Samples.

PubMed

Dehbozorgi, A; Tashkhourian, J; Zare, S

2015-11-01

In this study, some effort has been performed to provide low temperature, less time consuming and facile routes for the synthesis of CdTe quantum dots using ultrasound and water soluble capping agent thioglycolic acid. TGA-capped CdTe quantum dots were characterized through x-ray diffraction, transmission electron microscopy, Fourier transform infrared, ultraviolet-visible and fluorescence spectroscopy. The prepared quantum dots were used for warfarin determination based on the quenching of the fluorescence intensity in aqueous solution. Under the optimized conditions, the linear range of quantum dots fluorescence intensity versus the concentration of warfarin was 0.1-160.0 μM, with the correlation coefficient of 0.9996 and a limit of detection of 77.5 nM. There was no interference to coexisting foreign substances. The selectivity of the sensor was also tested and the results show that the developed method possesses a high selectivity for warfarin.

HMPT: Hazardous Waste Transportation Live 27928, Test 27929

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

Simpson, Lewis Edward

2016-03-17

HMPT: Hazardous Waste Transportation (Live 27928, suggested one time and associated Test 27929, required initially and every 36 months) addresses the Department of Transportation (DOT) function-specific training requirements of the hazardous materials packagings and transportation (HMPT) Los Alamos National Laboratory (LANL) lab-wide training. This course addresses the requirements of the DOT that are unique to hazardous waste shipments. Appendix B provides the Title 40 Code of Federal Regulations (CFR) reference material needed for this course.

US Rocket Propulsion Industrial Base Health Metrics

NASA Technical Reports Server (NTRS)

Doreswamy, Rajiv

2013-01-01

The number of active liquid rocket engine and solid rocket motor development programs has severely declined since the "space race" of the 1950s and 1960s center dot This downward trend has been exacerbated by the retirement of the Space Shuttle, transition from the Constellation Program to the Space launch System (SLS) and similar activity in DoD programs center dot In addition with consolidation in the industry, the rocket propulsion industrial base is under stress. To Improve the "health" of the RPIB, we need to understand - The current condition of the RPIB - How this compares to past history - The trend of RPIB health center dot This drives the need for a concise set of "metrics" - Analogous to the basic data a physician uses to determine the state of health of his patients - Easy to measure and collect - The trend is often more useful than the actual data point - Can be used to focus on problem areas and develop preventative measures The nation's capability to conceive, design, develop, manufacture, test, and support missions using liquid rocket engines and solid rocket motors that are critical to its national security, economic health and growth, and future scientific needs. center dot The RPIB encompasses US government, academic, and commercial (including industry primes and their supplier base) research, development, test, evaluation, and manufacturing capabilities and facilities. center dot The RPIB includes the skilled workforce, related intellectual property, engineering and support services, and supply chain operations and management. This definition touches the five main segments of the U.S. RPIB as categorized by the USG: defense, intelligence community, civil government, academia, and commercial sector. The nation's capability to conceive, design, develop, manufacture, test, and support missions using liquid rocket engines and solid rocket motors that are critical to its national security, economic health and growth, and future scientific needs. center dot The RPIB encompasses US government, academic, and commercial (including industry primes and their supplier base) research, development, test, evaluation, and manufacturing capabilities and facilities. center dot The RPIB includes the skilled workforce, related intellectual property, engineering and support services, and supply chain operations and management. This definition touches the five main segments of the U.S. RPIB as categorized by the USG: defense, intelligence community, civil government, academia, and commercial sector.

Synergetic effect of functional cadmium–tellurium quantum dots conjugated with gambogic acid for HepG2 cell-labeling and proliferation inhibition

PubMed Central

Xu, Peipei; Li, Jingyuan; Shi, Lixin; Selke, Matthias; Chen, Baoan; Wang, Xuemei

2013-01-01

We prepared and studied novel fluorescent nanocomposites based on gambogic acid (GA) and cadmium–tellurium (CdTe) quantum dots (CdTe QDs) modified with cysteamine for purpose of cancer cell labeling and combined treatment. The nanocomposites were denoted as GA-CdTe. Characterization results indicated that the CdTe QDs can readily bind onto cell plasma membranes and then be internalized into cancer cells for real-time labeling and tracing of human liver hepatocellular carcinoma cell line (HepG2) cells. GA-CdTe significantly enhanced drug accumulation in HepG2 cells and inhibited cancer cell proliferation. GA-CdTe nanocomposites also improved the drug action of GA molecules in HepG2 cells and induced the G2/M phase arrest of the cancer cell cycle, promoting cell apoptosis. Given the sensitive, pH-triggered release of GA-CdTe, the side effects of GA anticancer agents on normal cells/tissues in the blood circulation markedly decreased. Efficient drug release and accumulation in target tumor cells were also facilitated. Thus, the fluorescent GA-CdTe offered a new strategy for potential multimode cancer therapy and provided new channels for research into naturally-active compounds extracted from traditional Chinese medicinal plants. PMID:24109183

Synergetic effect of functional cadmium-tellurium quantum dots conjugated with gambogic acid for HepG2 cell-labeling and proliferation inhibition.

PubMed

Xu, Peipei; Li, Jingyuan; Shi, Lixin; Selke, Matthias; Chen, Baoan; Wang, Xuemei

2013-01-01

We prepared and studied novel fluorescent nanocomposites based on gambogic acid (GA) and cadmium-tellurium (CdTe) quantum dots (CdTe QDs) modified with cysteamine for purpose of cancer cell labeling and combined treatment. The nanocomposites were denoted as GA-CdTe. Characterization results indicated that the CdTe QDs can readily bind onto cell plasma membranes and then be internalized into cancer cells for real-time labeling and tracing of human liver hepatocellular carcinoma cell line (HepG2) cells. GA-CdTe significantly enhanced drug accumulation in HepG2 cells and inhibited cancer cell proliferation. GA-CdTe nanocomposites also improved the drug action of GA molecules in HepG2 cells and induced the G2/M phase arrest of the cancer cell cycle, promoting cell apoptosis. Given the sensitive, pH-triggered release of GA-CdTe, the side effects of GA anticancer agents on normal cells/tissues in the blood circulation markedly decreased. Efficient drug release and accumulation in target tumor cells were also facilitated. Thus, the fluorescent GA-CdTe offered a new strategy for potential multimode cancer therapy and provided new channels for research into naturally-active compounds extracted from traditional Chinese medicinal plants.

"Turn-off" fluorescent data array sensor based on double quantum dots coupled with chemometrics for highly sensitive and selective detection of multicomponent pesticides.

PubMed

Fan, Yao; Liu, Li; Sun, Donglei; Lan, Hanyue; Fu, Haiyan; Yang, Tianming; She, Yuanbin; Ni, Chuang

2016-04-15

As a popular detection model, the fluorescence "turn-off" sensor based on quantum dots (QDs) has already been successfully employed in the detections of many materials, especially in the researches on the interactions between pesticides. However, the previous studies are mainly focused on simple single track or the comparison based on similar concentration of drugs. In this work, a new detection method based on the fluorescence "turn-off" model with water-soluble ZnCdSe and CdSe QDs simultaneously as the fluorescent probes is established to detect various pesticides. The fluorescence of the two QDs can be quenched by different pesticides with varying degrees, which leads to the differences in positions and intensities of two peaks. By combining with chemometrics methods, all the pesticides can be qualitative and quantitative respectively even in real samples with the limit of detection was 2 × 10(-8) mol L(-1) and a recognition rate of 100%. This work is, to the best of our knowledge, the first report on the detection of pesticides based on the fluorescence quenching phenomenon of double quantum dots combined with chemometrics methods. What's more, the excellent selectivity of the system has been verified in different mediums such as mixed ion disruption, waste water, tea and water extraction liquid drugs. Copyright © 2016 Elsevier B.V. All rights reserved.

Acute Effects of Plyometric and Resistance Training on Running Economy in Trained Runners.

PubMed

Marcello, Richard T; Greer, Beau K; Greer, Anna E

2017-09-01

Marcello, RT, Greer, BK, and Greer, AE. Acute effects of plyometric and resistance training on running economy in trained runners. J Strength Cond Res 31(9): 2432-2437, 2017-Results regarding the acute effects of plyometrics and resistance training (PRT) on running economy (RE) are conflicting. Eight male collegiate distance runners (21 ± 1 years, 62.5 ± 7.8 ml·kg·min V[Combining Dot Above]O2 peak) completed V[Combining Dot Above]O2 peak and 1 repetition maximum (1RM) testing. Seven days later, subjects completed a 12 minutes RE test at 60 and 80% V[Combining Dot Above]O2 peak, followed by a PRT protocol or a rested condition of equal duration (CON). The PRT protocol consisted of 3 sets of 5 repetitions at 85% 1RM for barbell squats, Romanian deadlifts, and barbell lunges; the same volume was used for resisted lateral lunges, box jumps, and depth jumps. Subjects completed another RE test immediately after the treatments and 24 hours later. Subjects followed an identical protocol 6 days later with condition assignment reversed. Running economy was determined by both relative V[Combining Dot Above]O2 (ml·kg·min) and energy expenditure (EE) (kcal·min). There was a significant (p ≤ 0.05) between-trial increase in V[Combining Dot Above]O2 (37.1 ± 4.2 ml·kg·min PRT vs. 35.5 ± 3.9 ml·kg·min CON) and EE (11.4 ± 1.3 kcal·min PRT vs. 11.0 ± 1.4 kcal·min CON) immediately after PRT at 60% V[Combining Dot Above]O2 peak, but no significant changes were observed at 80% V[Combining Dot Above]O2 peak. Respiratory exchange ratio was significantly (p ≤ 0.05) reduced 24 hours after PRT (0.93 ± 0.0) as compared to the CON trial (0.96 ± 0.0) at 80% V[Combining Dot Above]O2 peak. Results indicate that high-intensity PRT may acutely impair RE in aerobically trained individuals at a moderate running intensity, but that the attenuation lasts less than 24 hours in duration.

Children with autism can track others' beliefs in a competitive game.

PubMed

Peterson, Candida C; Slaughter, Virginia; Peterson, James; Premack, David

2013-05-01

Theory of mind (ToM) development, assessed via 'litmus' false belief tests, is severely delayed in autism, but the standard testing procedure may underestimate these children's genuine understanding. To explore this, we developed a novel test involving competition to win a reward as the motive for tracking other players' beliefs (the 'Dot-Midge task'). Ninety-six children, including 23 with autism (mean age: 10.36 years), 50 typically developing 4-year-olds (mean age: 4.40) and 23 typically developing 3-year-olds (mean age: 3.59) took a standard 'Sally-Ann' false belief test, the Dot-Midge task (which was closely matched to the Sally-Ann task procedure) and a norm-referenced verbal ability test. Results revealed that, of the children with autism, 74% passed the Dot-Midge task, yet only 13% passed the standard Sally-Ann procedure. A similar pattern of performance was observed in the older, but not the younger, typically developing control groups. This finding demonstrates that many children with autism who fail motivationally barren standard false belief tests can spontaneously use ToM to track their social partners' beliefs in the context of a competitive game. © 2013 Blackwell Publishing Ltd.

[Patient-centered medicine for tuberculosis medical services].

PubMed

Fujita, Akira; Narita, Tomoyo

2012-12-01

The 2011 edition of Specific Guiding Principles for Tuberculosis Prevention calls for a streamlined medical services system capable of providing medical care that is customized to the patient's needs. The new 21st Century Japanese version of the Directly Observed Treatment Short Course (DOTS) expands the indication of DOTS to all tuberculosis (TB) patients in need of treatment. Hospital DOTS consists of comprehensive, patient-centered support provided by a DOTS care team. For DOTS in the field, health care providers should select optimal administration support based on patient profiles and local circumstances. In accordance with medical fee revisions for 2012, basic inpatient fees have been raised and new standards for TB hospitals have been established, the result of efforts made by the Japanese Society for Tuberculosis and other associated groups. It is important that the medical care system be improved so that patients can actively engage themselves as a member of the team, for the ultimate goal of practicing patient-centered medicine. We have organized this symposium to explore the best ways for practicing patient-centered medicine in treating TB. It is our sincere hope that this symposium will lead to improved medical treatment for TB patients. 1. Providing patient-centered TB service via utilization of collaborative care pathway: Akiko MATSUOKA (Hiroshima Prefectural Tobu Public Health Center) We have been using two types of collaborative care pathway as one of the means of providing patient-centered TB services since 2008. The first is the clinical pathway, which is mainly used by TB specialist doctors to communicate with local practitioners on future treatment plan (e.g. medication and treatment duration) of patients. The clinical pathway was first piloted in Onomichi district and its use was later expanded to the whole of Hiroshima prefecture. The second is the regional care pathway, which is used to share treatment progress, test results and other necessary patient information among the relevant parties. The regional care pathway was developed by the Tobu Public Health Center. It is currently being used by several other public health centers in Hiroshima. Utilization of these two pathways has resulted in improved adherence, treatment being offered at local clinics, shorter hospitalization and better treatment outcomes. 2. Patient-centered DOTS in Funabashi-city: Akiko UOZUMI (Funabashi-city Public Health Center) In Funabashi-city, all TB patients, including those with LTBI, are treated under DOTS which recognizes and tries to accommodate the various different needs of each individual patient. For example, various types of DOTS are offered, such as pharmacy-based DOTS and DOTS supported by caregivers of nursing homes. This enables public health nurses to take into consideration both the results of risk assessment and convenience for the patient, and choose DOTS which most effectively support the patient. Furthermore, DOTS in principle is offered face-to-face, so that DOTS providers may not only build relationship of trust with the patient, but also to collect and analyze the necessary information regarding the patient and respond timely when problems arise. Such effort has directly contributed to improved default and treatment rate. 3. Hospital DOTS and clinical path for the treatment of tuberculosis: Kentaro SAKASHITA, Akira FUJITA (Tokyo Metropolitan Tama Medical Center) We introduced a version of hospital DOTS at Tama Medical Center (formerly Fuchu Hospital) in 2004. As part of this three-stage version, patients are allowed to progress to the next stage if they meet the step-up criteria. Following the introduction of this hospital DOTS, the occurrence of drug administration-related incidents decreased and support for patient adherence became easier for health care workers than before. In 2006, we developed a clinical path based on this hospital DOTS with consistent eligibility criteria for patients. This clinical path helped increase the efficiency of medical services in the TB ward. In conclusion, a patient's initiative for tuberculosis treatment can be supported through our hospital's TB treatment system. 4. Survey of TB patients' understanding and satisfaction of hospital DOTS: Yoko NAGATA, Minako URAKAWA, Noriko KOBAYASHI, Seiya KATO (Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association) We surveyed the satisfaction and understanding of recently discharged TB patients regarding DOTS to analyze how to better implement DOTS. The questionnaire consisted of nine items covering knowledge of TB, comfort in talking to and asking questions of the medical staff, explanations given to family members, and motivation for continuing medication. Two hundred and eight of the 228 patients who accepted the questionnaire responded (response rate: 91.2%). The level of understanding and satisfaction tended to be higher among patients in hospitals that employed a primary nursing system, more coverage and duration of DOT, and audiovisual materials for patient education. The level of understanding and satisfaction also tended to be slightly higher among institutions that conducted in-hospital conferences and collaborated with public health centers more frequently. 5. Medical cooperative system against tuberculosis elimination: Dai YOSHIZAWA (Tuberculosis and Infectious disease control division, Ministry of Health, Labour and Welfare) There are 3 points we should consider. First, despite one of the intermediate burden countries, emphasis for infectious incidence is insufficient. Besides new incidence decreases gradually, increased ratio of the elderly causes necessity of implementation against each complications. The second is how find infectious one, especially from high burden countries, before they spread it. Final, unspecific symptoms suffer the patients and medical staff. It's the key of implementation that spread of tuberculosis must be caused by delayed diagnosis.

Reliability and Accuracy of a Standardized Shallow Water Running Test to Determine Cardiorespiratory Fitness.

PubMed

Nagle, Elizabeth F; Sanders, Mary E; Gibbs, Bethany B; Franklin, Barry A; Nagle, Jacquelyn A; Prins, Philip J; Johnson, Caleb D; Robertson, Robert J

2017-06-01

A standardized fitness assessment is critical for the development of an individualized exercise prescription. Although the benefits of aquatic exercise have been well established, there remains the need for a standardized nonswimming protocol to accurately assess cardiorespiratory fitness (CRF) in shallow water. The present investigation was designed to assess (a) the reliability of a standardized shallow water run (SWR) test of CRF and (b) the accuracy of a standardized SWR compared with a land-based treadmill (LTM) test. Twenty-three healthy women (20 ± 3 years), with body mass index (23.5 ± 3 kg·m), performed 2 shallow water peak oxygen consumption (V[Combining Dot Above]O2peak) running tests (SWRa and SWRb), and 1 V[Combining Dot Above]O2max LTM. Intraclass correlation coefficients indicated moderately strong reliability for V[Combining Dot Above]O2peak (ml·kg·min) (r = 0.73, p < 0.01), HRpeak (b·min) (r = 0.82; p < 0.01), and O2pulse (V[Combining Dot Above]O2 [ml·kg·min]·HR [b·min]) (r = 0.77, p < 0.01). Using paired t-tests and Pearson's correlations, SWR V[Combining Dot Above]O2peak and HRpeak were significantly lower than during LTM (p ≤ 0.05) and showed moderate correlations of 0.60 and 0.58 (p < 0.001) to LTM. O2pulse was similar (p > 0.05) for the SWR and LTM tests with a moderate correlation of 0.63. A standardized SWR test as a measure of CRF is a reliable, and to some degree, valid alternative to conventional protocols and may be used by strength and conditioning professionals to measure program outcomes and monitor training progress. Furthermore, this protocol provides a water-based option for CRF assessment among healthy women and offers insight toward the development of an effective protocol that can accommodate individuals with limited mobility, or those seeking less musculoskeletal impact from traditional land-based types of training.

Simultaneous monitoring of multiple contrast agents using a hybrid MR-DOT system

NASA Astrophysics Data System (ADS)

Gulsen, Gultekin; Unlu, Mehmet Burcin; Birgul, Ozlem; Nalcioglu, Orhan

2007-02-01

Frequency domain diffuse optical tomography (DOT) is a recently emerging technique that uses arrays of sources and detectors to obtain spatially dependent optical parameters of tissue. Here, we describe the design of a hybrid MR-DOT system for dynamic imaging cancer. The combined system acquires both MR and optical data simultaneously. The performance of the system is tested with phantom and in-vivo studies. Gd-DTPA and ICG was used for this purpose and the enhancement kinetics of both agents are recorded using the hybrid system.

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

Feasibility of interstitial diffuse optical tomography using cylindrical diffusing fiber for prostate PDT

PubMed Central

Liang, Xing; Wang, Ken Kang-Hsin; Zhu, Timothy C.

2013-01-01

Interstitial diffuse optical tomography (DOT) has been used to characterize spatial distribution of optical properties for prostate photodynamic therapy (PDT) dosimetry. We have developed an interstitial DOT method using cylindrical diffuse fibers (CDFs) as light sources, so that the same light sources can be used for both DOT measurement and PDT treatment. In this novel interstitial CDF-DOT method, absolute light fluence per source strength (in unit of 1/cm2) is used to separate absorption and scattering coefficients. A mathematical phantom and a solid prostate phantom including anomalies with known optical properties were used, respectively, to test the feasibility of reconstructing optical properties using interstitial CDF-DOT. Three dimension spatial distributions of the optical properties were reconstructed for both scenarios. Our studies show that absorption coefficient can be reliably extrapolated while there are some cross talks between absorption and scattering properties. Even with the suboptimal reduced scattering coefficients, the reconstructed light fluence rate agreed with the measured values to within ±10%, thus the proposed CDF-DOT allows greatly improved light dosimetry calculation for interstitial PDT. PMID:23629149

[Tuberculosis control in Shinjuku Ward, Tokyo--promoting the DOTS program and its outcome].

PubMed

Kaguraoka, Sumi; Ohmori, Masako; Takao, Yoshiko; Yamada, Mari; Muroi, Masako; Nagamine, Michiko; Fukazawa, Keiji; Nagai, Megumi; Wada, Masako; Hoshino, Hitoshi; Yoshiyama, Takashi; Maeda, Hideo; Ishikawa, Nobukatsu

2008-09-01

The objectives were to report how to promote tuberculosis (TB) control including DOTS (Directly Observed Treatment, Short-course) programs, and to evaluate the results of TB control programs in Shinjuku Ward (Shinjuku-ku). SETTING AND CHARACTERISTICS: Inhabitants and TB patients in Shinjuku Ward. Shinjuku Ward is located in the center of metropolitan Tokyo and has typical urban TB problems, such as high incidence rate and TB among foreigners and the homeless. The TB incidence rates in Shinjuku Ward decreased from 83.9 per 100,000 population in 1999 to 42.5 per 100,000 population in 2006, however, the rates were still two times higher than the national average. Therefore, one of the important TB programs in Shinjuku has been to actively detect cases among high-risk groups such as foreigners and the homeless. We observed the trend of case detection rates by health examination with chest X-ray among different high-risk groups, and compared the treatment outcomes before and after DOTS program execution. We also reviewed the changes of re-treatment rates and drug resistance rates. The case detection rates of TB by health examinations of foreign students at Japanese language schools decreased from 0.49% in 1996 to 0.13% in 2006 (p = 0.021). Although the case detection rates decreased, they were still about 26 times higher than those of Japanese students. While, the case detection rates among the homeless remained high with 4.7%, 3.3%, 4.5% and 3.6% in 1999-2002, respectively, since 2003, however, they had decreased and no TB cases were detected in 2005-2006. The DOTS program for homeless TB patients has been carried out since 2000 and that for the foreigners since 2003. The rates of defaulting during treatment before DOTS were very high among both homeless patients (21.4%) and foreigners (29.8%) in 1998-1999. However, after the introduction of DOTS program, those rates declined to 10.4% (p = 0.014) among the homeless and 7.8% (p = 0.002) among foreigners in 2002-2004. The proportion of newly notified patients with previous TB treatment and those with multi-drug resistant TB (MDR-TB) have also decreased after the introduction of DOTS programs. From 2000-2002 to 2003-2006, the re-treatment rates decreased from 19.4% to 10.0% (p < 0.001) and MDR-TB rates decreased from 1.6% to 0.2% (p = 0.042), respectively. The key points of TB control in Shinjuku Ward are to detect TB cases early especially among the high-risk groups, and to assist all TB patients to complete their treatment. In order to expand this strategy, besides promoting active case findings among high-risk groups, we have developed many types of DOTS programs, considering each patient's lifestyle and cooperating with school teachers at schools, pharmacists at pharmacies, home-care specialists at homes or facilities for the elderly, and so on. Among others, a major premise for the homeless and some other socially disadvantaged patients was to guarantee the provision of medicine and living by introducing social welfare services, before starting DOTS programs. This approach might have helped to reduce the defaulting rate, relapse rate and MDR-TB rate.

Temporal stability of visual search-driven biometrics

NASA Astrophysics Data System (ADS)

Yoon, Hong-Jun; Carmichael, Tandy R.; Tourassi, Georgia

2015-03-01

Previously, we have shown the potential of using an individual's visual search pattern as a possible biometric. That study focused on viewing images displaying dot-patterns with different spatial relationships to determine which pattern can be more effective in establishing the identity of an individual. In this follow-up study we investigated the temporal stability of this biometric. We performed an experiment with 16 individuals asked to search for a predetermined feature of a random-dot pattern as we tracked their eye movements. Each participant completed four testing sessions consisting of two dot patterns repeated twice. One dot pattern displayed concentric circles shifted to the left or right side of the screen overlaid with visual noise, and participants were asked which side the circles were centered on. The second dot-pattern displayed a number of circles (between 0 and 4) scattered on the screen overlaid with visual noise, and participants were asked how many circles they could identify. Each session contained 5 untracked tutorial questions and 50 tracked test questions (200 total tracked questions per participant). To create each participant's "fingerprint", we constructed a Hidden Markov Model (HMM) from the gaze data representing the underlying visual search and cognitive process. The accuracy of the derived HMM models was evaluated using cross-validation for various time-dependent train-test conditions. Subject identification accuracy ranged from 17.6% to 41.8% for all conditions, which is significantly higher than random guessing (1/16 = 6.25%). The results suggest that visual search pattern is a promising, temporally stable personalized fingerprint of perceptual organization.

Workflow efficiency of two 1.5 T MR scanners with and without an automated user interface for head examinations.

PubMed

Moenninghoff, Christoph; Umutlu, Lale; Kloeters, Christian; Ringelstein, Adrian; Ladd, Mark E; Sombetzki, Antje; Lauenstein, Thomas C; Forsting, Michael; Schlamann, Marc

2013-06-01

Workflow efficiency and workload of radiological technologists (RTs) were compared in head examinations performed with two 1.5 T magnetic resonance (MR) scanners equipped with or without an automated user interface called "day optimizing throughput" (Dot) workflow engine. Thirty-four patients with known intracranial pathology were examined with a 1.5 T MR scanner with Dot workflow engine (Siemens MAGNETOM Aera) and with a 1.5 T MR scanner with conventional user interface (Siemens MAGNETOM Avanto) using four standardized examination protocols. The elapsed time for all necessary work steps, which were performed by 11 RTs within the total examination time, was compared for each examination at both MR scanners. The RTs evaluated the user-friendliness of both scanners by a questionnaire. Normality of distribution was checked for all continuous variables by use of the Shapiro-Wilk test. Normally distributed variables were analyzed by Student's paired t-test, otherwise Wilcoxon signed-rank test was used to compare means. Total examination time of MR examinations performed with Dot engine was reduced from 24:53 to 20:01 minutes (P < .001) and the necessary RT intervention decreased by 61% (P < .001). The Dot engine's automated choice of MR protocols was significantly better assessed by the RTs than the conventional user interface (P = .001). According to this preliminary study, the Dot workflow engine is a time-saving user assistance software, which decreases the RTs' effort significantly and may help to automate neuroradiological examinations for a higher workflow efficiency. Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.

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

Yoon, Hong-Jun; Carmichael, Tandy; Tourassi, Georgia

Previously, we have shown the potential of using an individual s visual search pattern as a possible biometric. That study focused on viewing images displaying dot-patterns with different spatial relationships to determine which pattern can be more effective in establishing the identity of an individual. In this follow-up study we investigated the temporal stability of this biometric. We performed an experiment with 16 individuals asked to search for a predetermined feature of a random-dot pattern as we tracked their eye movements. Each participant completed four testing sessions consisting of two dot patterns repeated twice. One dot pattern displayed concentric circlesmore » shifted to the left or right side of the screen overlaid with visual noise, and participants were asked which side the circles were centered on. The second dot-pattern displayed a number of circles (between 0 and 4) scattered on the screen overlaid with visual noise, and participants were asked how many circles they could identify. Each session contained 5 untracked tutorial questions and 50 tracked test questions (200 total tracked questions per participant). To create each participant s "fingerprint", we constructed a Hidden Markov Model (HMM) from the gaze data representing the underlying visual search and cognitive process. The accuracy of the derived HMM models was evaluated using cross-validation for various time-dependent train-test conditions. Subject identification accuracy ranged from 17.6% to 41.8% for all conditions, which is significantly higher than random guessing (1/16 = 6.25%). The results suggest that visual search pattern is a promising, fairly stable personalized fingerprint of perceptual organization.« less

Creep Shrinkage and CTE Evaluation: MoDOT's New Bridge Deck Mix Companion Testing to HPC Bridge Deck.

DOT National Transportation Integrated Search

2005-02-01

MoDOT RDT Research Project R-I00-002 HPC for Bridge A6130 Route 412 Pemiscot County was recently completed in June of 2004 [Myers and Yang, 2004]. Among other research tasks, part of this research study investigated the creep, shrinkage and...

75 FR 20040 - Waiver Extension Request

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-16

... equipment and testing, commencing in the summer of 2011, for a period of 39 months, or approval of a..., etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (Volume 65, Number 70; Pages 19477-78) or at http://dot.gov/privacy.html . Issued in...

MASH Test 3-11 on the T131RC Bridge Rail

DOT National Transportation Integrated Search

2012-10-01

Texas Department of Transportation (TxDOT) currently uses the TxDOT Type T101RC Bridge Rail, : a steel post and beam bridge rail anchored to the top of concrete curbs. The T101RC Bridge Rail is : 27 inches in height and can be anchored to the top of ...

Micro Dot Patterning on the Light Guide Panel Using Powder Blasting.

PubMed

Jang, Ho Su; Cho, Myeong Woo; Park, Dong Sam

2008-02-08

This study is to develop a micromachining technology for a light guidepanel(LGP) mold, whereby micro dot patterns are formed on a LGP surface by a singleinjection process instead of existing screen printing processes. The micro powder blastingtechnique is applied to form micro dot patterns on the LGP mold surface. The optimalconditions for masking, laminating, exposure, and developing processes to form the microdot patterns are first experimentally investigated. A LGP mold with masked micro patternsis then machined using the micro powder blasting method and the machinability of themicro dot patterns is verified. A prototype LGP is test- injected using the developed LGPmold and a shape analysis of the patterns and performance testing of the injected LGP arecarried out. As an additional approach, matte finishing, a special surface treatment method,is applied to the mold surface to improve the light diffusion characteristics, uniformity andbrightness of the LGP. The results of this study show that the applied powder blastingmethod can be successfully used to manufacture LGPs with micro patterns by just singleinjection using the developed mold and thereby replace existing screen printing methods.

Tuberculosis drug issues: prices, fixed-dose combination products and second-line drugs.

PubMed

Laing, R O; McGoldrick, K M

2000-12-01

Access to tuberculosis drugs depends on multiple factors. Selection of a standard list of TB drugs to procure is the first step. This paper reviews the advantages and disadvantages of procuring and using fixed-dose combination (FDC) products for both the intensive and continuation phases of treatment. The major advantages are to prevent the emergence of resistance, to simplify logistic management and to reduce costs. The major disadvantage is the need for the manufacturers to assure the quality of these FDCs by bioavailability testing. The paper reports on the inclusion of second-line TB drugs in the 1999 WHO Essential Drug List (EDL). The need to ensure that these drugs are used within established DOTS-Plus programs is stressed. The price of TB drugs is determined by many factors, including producer prices, local taxes and duties as well as mark-ups and fees. TB drug prices for both the public and private sectors from industrialized and developing countries are reported. Price trends over time are also reported. The key findings of this study are that TB drug prices have generally declined in developing countries while they have increased in developed countries, both for the public and private sectors. Prices vary between countries, with the US paying as much as 95 times the price paid in a specific developing country. The prices of public sector first-line TB drugs vary little between countries, although differences do exist due to the procurement methods used. The price of tuberculin, a diagnostic agent, has increased dramatically in the US, with substantial inter-country variations in price. The paper suggests that further research is necessary to identify the reasons for the price disparities and changes over time, and suggests methods which can be used by National Tuberculosis Programme managers to ensure availability of quality assured TB drugs at low prices.

Daunorubicin and gambogic acid coloaded cysteamine-CdTe quantum dots minimizing the multidrug resistance of lymphoma in vitro and in vivo

PubMed Central

Zhou, Yi; Wang, Ruju; Chen, Bing; Sun, Dan; Hu, Yong; Xu, Peipei

2016-01-01

To minimize the side effects and the multidrug resistance (MDR) arising from daunorubicin (DNR) treatment of malignant lymphoma, a chemotherapy formulation of cysteamine-modified cadmium tellurium (Cys-CdTe) quantum dots coloaded with DNR and gambogic acid (GA) nanoparticles (DNR-GA-Cys-CdTe NPs) was developed. The physical property, drug-loading efficiency and drug release behavior of these DNR-GA-Cys-CdTe NPs were evaluated, and their cytotoxicity was explored by 3-[4,5-dimethylthiazol-2-y1]-2,5-diphenyltetrazolium bromide assay. These DNR-GA-Cys-CdTe NPs possessed a pH-responsive behavior, and displayed a dose-dependent antiproliferative activity on multidrug-resistant lymphoma Raji/DNR cells. The accumulation of DNR inside the cells, revealed by flow cytometry assay, and the down-regulated expression of P-glycoprotein inside the Raji/DNR cells measured by Western blotting assay indicated that these DNR-GA-Cys-CdTe NPs could minimize the MDR of Raji/DNR cells. This multidrug delivery system would be a promising strategy for minimizing MDR against the lymphoma. PMID:27799767

Atmospheric chemistry of the reaction ClO + O2 reversible reaction ClO (center dot) O2: Where it stands, what needs to be done, and why?

NASA Technical Reports Server (NTRS)

Prasad, Sheo S.; Lee, Timothy J.

1994-01-01

Possible existence and chemistry of ClO (center dot) O2 was originally proposed to explain the Norrish-Neville effect that O2 suppresses chlorine photosensitized loss of ozone. It was also thought that ClO (center dot) O2 might have some atmospheric chemistry significance. Recently, doubts have been cast on this proposal, because certain laboratory data seem to imply that the equilibrium constant of the title reaction is so small that ClO (center dot) O2 may be too unstable to matter. However, those data create only a superficial illusion to that effect, because on a closer analysis they do not disprove a moderately stable and chemically significant ClO (center dot) O2. Furthermore, our state-of-the-science accurate computational chemistry calculations also suggest that ClO (center dot) O2 may be a weakly bound ClOOO radical with a reactive (2)A ground electronic state. There is therefore a need to design and perform definitive experimental tests of the existence and chemistry of the ClO (center dot) O2 species, which we discuss and which have the potential to mediate the chlorine-catalyzed stratospheric ozone depletion.

Specificity rates for non-clinical, bilingual, Mexican Americans on three popular performance validity measures.

PubMed

Gasquoine, Philip G; Weimer, Amy A; Amador, Arnoldo

2017-04-01

To measure specificity as failure rates for non-clinical, bilingual, Mexican Americans on three popular performance validity measures: (a) the language format Reliable Digit Span; (b) visual-perceptual format Test of Memory Malingering; and (c) visual-perceptual format Dot Counting, using optimal/suboptimal effort cut scores developed for monolingual, English-speakers. Participants were 61 consecutive referrals, aged between 18 and 65 years, with <16 years of education who were subjectively bilingual (confirmed via formal assessment) and chose the language of assessment, Spanish or English, for the performance validity tests. Failure rates were 38% for Reliable Digit Span, 3% for the Test of Memory Malingering, and 7% for Dot Counting. For Reliable Digit Span, the failure rates for Spanish (46%) and English (31%) languages of administration did not differ significantly. Optimal/suboptimal effort cut scores derived for monolingual English-speakers can be used with Spanish/English bilinguals when using the visual-perceptual format Test of Memory Malingering and Dot Counting. The high failure rate for Reliable Digit Span suggests it should not be used as a performance validity measure with Spanish/English bilinguals, irrespective of the language of test administration, Spanish or English.

Tuberculosis: a new vision for the 21st century.

PubMed

Small, Peter M

2009-11-01

Tuberculosis is a global problem that we can't afford to keep ignoring. In 2006, tuberculosis killed 1.7 million people--almost twice as many people as malaria--and it is the leading cause of death among people living with HIV/AIDS. This is all the more tragic because these deaths are preventable. For a long time the world thought that we had defeated tuberculosis, but just because tuberculosis doesn't make headlines doesn't mean it has gone away. The fact is that tuberculosis is getting worse, as complacency and lack of adequate tools and funding fuel the disease and the spread of drug resistance. Drug resistant tuberculosis is the wake-up call, it is an airborne epidemic of increasingly untreatable disease. Drug resistant tuberculosis develops when tuberculosis patients take low-quality drugs, do not finish their full course of treatment, or pass drug resistant tuberculosis from one person to another. In 2007, there were approximately 500,000 cases of drug resistant tuberculosis globally. MDR-TB is resistant to the two most commonly used first-line TB drugs, and requires long, complex and expensive treatment. XDR-TB is resistant to first- and second-line drugs, severely limiting treatment options. While progress is being made, much more is needed. Basic tuberculosis control is one of the most cost-effective interventions in global health. Appropriate treatment can save a life and stop the spread of disease for US$14. It is essential that countries implement the World Health Organization's (WHO) internationally recommended Stop TB strategy, which includes DOTS. But due to outdated tools and methods, DOTS alone is not enough. The remarkable fact is that global control of tuberculosis, a disease that kills someone every 20 seconds, depends upon a 125-year-old test, an 85-year-old vaccine and drugs that take six months to cure and haven't changed in four decades. To successfully treat tuberculosis and prevent resistance, we need to use current tools better and accelerate the development of new tools for the future. Simple improvements in tuberculosis control, such as expanding the use of under-utilized technologies, can have enormous impact. Fixed-dose combinations have existed for over 25 years, and could help ensure that more patients complete treatment; yet globally, only 15 percent of patients are using them. We also need new drugs, vaccines and diagnostics, as well as innovations in tuberculosis control and case management. Better diagnostics are already available, and new drugs and vaccines are coming. But more commitment and resources are needed. Better prevention and control of tuberculosis is the surest way to stop drug resistance. To ensure that drug resistance does not pose a wider threat, we need to employ a number of equally important approaches. These include improved basic tuberculosis control, increased use of underutilized technologies such as fixed-dose combinations, and new technologies and health systems innovations. At the same time, we should expand access to M/XDR-TB treatment and diagnostics for those who already have drug resistant tuberculosis. Some of the most innovative solutions can come from the private sector and through partnerships. An untapped market of two billion people carries the tuberculosis bacterium. Since tuberculosis requires a comprehensive approach, companies should also explore opportunities to work together and pool complementary technologies to ensure new tools are used most effectively. Japan is poised to play a leading role in the discovery, development and delivery of tuberculosis solutions in the 21st century.

D-GENIES: dot plot large genomes in an interactive, efficient and simple way.

PubMed

Cabanettes, Floréal; Klopp, Christophe

2018-01-01

Dot plots are widely used to quickly compare sequence sets. They provide a synthetic similarity overview, highlighting repetitions, breaks and inversions. Different tools have been developed to easily generated genomic alignment dot plots, but they are often limited in the input sequence size. D-GENIES is a standalone and web application performing large genome alignments using minimap2 software package and generating interactive dot plots. It enables users to sort query sequences along the reference, zoom in the plot and download several image, alignment or sequence files. D-GENIES is an easy-to-install, open-source software package (GPL) developed in Python and JavaScript. The source code is available at https://github.com/genotoul-bioinfo/dgenies and it can be tested at http://dgenies.toulouse.inra.fr/.

Validity and Reliability of an on-Court Fitness Test for Assessing and Monitoring Aerobic Fitness in Squash.

PubMed

James, Carl Alexander; Vallejo, Florencio Tenllado; Kantebeen, Melvin; Farra, Saro

2018-02-14

Current on-court assessments of aerobic fitness in squash are not designed to yield a wealth of physiological data. Moreover, tests may require complex computer equipment or involve simulated racket strokes, which are difficult to standardize at high intensities. This study investigated the validity and reliability of a squash-specific fitness test which can yield both a standalone performance score, as well as pertinent physiological markers such as V[Combining Dot Above]O2max, the lactate turnpoint and oxygen cost, in a sport-specific environment. Eight national squash players completed three tests in a counter-balanced order; an incremental laboratory treadmill test (LAB) and two on-court fitness tests (ST) that involved repeated shuttle runs at increasing speeds. V[Combining Dot Above]O2max during ST was agreeable with LAB (Typical error [TE]=3.3 mL.kg.min, r=0.79). The mean bias between LAB and ST was 2.5 mL.kg.min. There were no differences in maximum heart rate, post exercise blood lactate concentration or end of test RPE between LAB and ST (p>0.05). The ST was highly reliable, with 74 (10) laps completed in ST1 and 75 (12) laps in ST2 (mean bias=1 lap, TE=3 laps, r=0.97). Physiological markers were also reliable, including V[Combining Dot Above]O2max, (TE=1.5 mL.kg.min, r=0.95), the lap number at 4 mMol (TE=4 laps, r=0.77) and average VO2 across the first 4 stages (TE=0.94 mL.kg.min, r=0.95). We observed good agreement between LAB and ST for assessing V[Combining Dot Above]O2max and between both on-court trials for assessing test performance and selected physiological markers. Consequently, we recommend this test for monitoring training adaptations and prescribing individualized training in elite squash players.

Peptide-coated semiconductor quantum dots and their applications in biological imaging of single molecules in live cells and organisms

NASA Astrophysics Data System (ADS)

Pinaud, Fabien Florent

2007-12-01

A new surface chemistry has been developed for the solubilization and biofunctionalization of inorganic semiconductor nanocrystals fluorescent probes, also known as quantum dots. This chemistry is based on the surface coating of quantum dots with custom-designed polycysteine peptides and yields water-soluble, small, monodispersed and colloidally stable probes that remain bright and photostable in complex biological milieus. This peptide coating strategy was successfully tested on several types of core and core-shell quantum dots emitting from the visible (e.g. CdSe/ZnS) to the NIR spectrum range (e.g. CdTe/CdSe/ZnS). By taking advantage of the versatile physico-chemical properties of peptides, a peptide "toolkit" was designed and employed to impart several biological functions to individual quantum dots and control their biochemical activity at the nanometer scale. These biofunctionalized peptide-coated quantum dots were exploited in very diverse biological applications. Near-infrared emitting quantum dot probes were engineered with optimized blood circulation and biodistribution properties for in vivo animal imaging. Visible emitting quantum dots were used for single molecule tracking of raft-associated GPI-anchored proteins in live cells. This last application revealed the presence of discrete and non-caveolar lipid microdomains capable of impeding free lateral diffusions in the plasma membrane of Hela cells. Imaging and tracking of peptide-coated quantum dots provided the first direct evidence that microdomains having the composition and behavior expected for lipid rafts can induce molecular compartmentalization in the membrane of living cells.

Selective solvent-free chromium detection using cadmium-free quantum dots

NASA Astrophysics Data System (ADS)

Meylemans, Heather A.; Baca, Alfred J.; Cambrea, Lee R.; Ostrom, Gregory S.

2017-07-01

Currently, the method of choice to test for the presence of chromium in water is to submit samples to a lab for testing. We present a simple field-ready test that is selective for the presence of chromium at concentrations of 100 ppb or greater. The Environmental Protection Agency maximum contaminant level (MCL) for total chromium is 100 ppb. This test uses a simple on/off fluorescent screening employing the use of silver indium sulfide (AgInS2) quantum dots (QDs). These QDs were impregnated into cotton pads to simplify field testing without the need for solvents or other liquid chemicals to be present. The change in fluorescence is instant and can be readily observed by eye with the use of a UV flashlight.

Connecting the Moving Dots - Continuum Magazine | NREL

Science.gov Websites

situation," Hurlbut said. After the 2011 request, NREL analysts burned a different kind of fuel Macknick tests water by the Excel Zuni Power Plant in Commerce City, Colorado. Photo by Dennis Schroeder , NREL Connecting the Moving Dots Systems-level thinking illuminates the connections among energy, the

MnDOT 2014 peer exchange : quantifying & communicating the value of research implementation for MnROAD phase-II research projects and development of MnROAD's future research.

DOT National Transportation Integrated Search

2014-06-01

MnDOT Research Services hosted a national peer exchange in Minneapolis, Minnesota from June 10-12, : 2014, that focused on the research and implementation efforts of the MnROAD cold region pavement : testing facility and laboratory. The goal of the p...

Design strategy for terahertz quantum dot cascade lasers.

PubMed

Burnett, Benjamin A; Williams, Benjamin S

2016-10-31

The development of quantum dot cascade lasers has been proposed as a path to obtain terahertz semiconductor lasers that operate at room temperature. The expected benefit is due to the suppression of nonradiative electron-phonon scattering and reduced dephasing that accompanies discretization of the electronic energy spectrum. We present numerical modeling which predicts that simple scaling of conventional quantum well based designs to the quantum dot regime will likely fail due to electrical instability associated with high-field domain formation. A design strategy adapted for terahertz quantum dot cascade lasers is presented which avoids these problems. Counterintuitively, this involves the resonant depopulation of the laser's upper state with the LO-phonon energy. The strategy is tested theoretically using a density matrix model of transport and gain, which predicts sufficient gain for lasing at stable operating points. Finally, the effect of quantum dot size inhomogeneity on the optical lineshape is explored, suggesting that the design concept is robust to a moderate amount of statistical variation.

Continuous distribution of emission states from single CdSe/ZnS quantum dots.

PubMed

Zhang, Kai; Chang, Hauyee; Fu, Aihua; Alivisatos, A Paul; Yang, Haw

2006-04-01

The photoluminescence dynamics of colloidal CdSe/ZnS/streptavidin quantum dots were studied using time-resolved single-molecule spectroscopy. Statistical tests of the photon-counting data suggested that the simple "on/off" discrete state model is inconsistent with experimental results. Instead, a continuous emission state distribution model was found to be more appropriate. Autocorrelation analysis of lifetime and intensity fluctuations showed a nonlinear correlation between them. These results were consistent with the model that charged quantum dots were also emissive, and that time-dependent charge migration gave rise to the observed photoluminescence dynamics.

Vector-mean-field theory of the fractional quantum Hall effect

NASA Astrophysics Data System (ADS)

Rejaei, B.; Beenakker, C. W. J.

1992-12-01

A mean-field theory of the fractional quantum Hall effect is formulated based on the adiabatic principle of Greiter and Wilczek. The theory is tested on known bulk properties (excitation gap, fractional charge, and statistics), and then applied to a confined region in a two-dimensional electron gas (quantum dot). For a small number N of electrons in the dot, the exact ground-state energy has cusps at the same angular momentum values as the mean-field theory. For large N, Wen's algebraic decay of the probability for resonant tunneling through the dot is reproduced, albeit with a different exponent.

Voltammetry as a Tool for Characterization of CdTe Quantum Dots

PubMed Central

Sobrova, Pavlina; Ryvolova, Marketa; Hubalek, Jaromir; Adam, Vojtech; Kizek, Rene

2013-01-01

Electrochemical detection of quantum dots (QDs) has already been used in numerous applications. However, QDs have not been well characterized using voltammetry, with respect to their characterization and quantification. Therefore, the main aim was to characterize CdTe QDs using cyclic and differential pulse voltammetry. The obtained peaks were identified and the detection limit (3 S/N) was estimated down to 100 fg/mL. Based on the convincing results, a new method for how to study stability and quantify the dots was suggested. Thus, the approach was further utilized for the testing of QDs stability. PMID:23807507

Ecological validity of virtual reality daily living activities screening for early dementia: longitudinal study.

PubMed

Tarnanas, Ioannis; Schlee, Winfried; Tsolaki, Magda; Müri, René; Mosimann, Urs; Nef, Tobias

2013-08-06

Dementia is a multifaceted disorder that impairs cognitive functions, such as memory, language, and executive functions necessary to plan, organize, and prioritize tasks required for goal-directed behaviors. In most cases, individuals with dementia experience difficulties interacting with physical and social environments. The purpose of this study was to establish ecological validity and initial construct validity of a fire evacuation Virtual Reality Day-Out Task (VR-DOT) environment based on performance profiles as a screening tool for early dementia. The objectives were (1) to examine the relationships among the performances of 3 groups of participants in the VR-DOT and traditional neuropsychological tests employed to assess executive functions, and (2) to compare the performance of participants with mild Alzheimer's-type dementia (AD) to those with amnestic single-domain mild cognitive impairment (MCI) and healthy controls in the VR-DOT and traditional neuropsychological tests used to assess executive functions. We hypothesized that the 2 cognitively impaired groups would have distinct performance profiles and show significantly impaired independent functioning in ADL compared to the healthy controls. The study population included 3 groups: 72 healthy control elderly participants, 65 amnestic MCI participants, and 68 mild AD participants. A natural user interface framework based on a fire evacuation VR-DOT environment was used for assessing physical and cognitive abilities of seniors over 3 years. VR-DOT focuses on the subtle errors and patterns in performing everyday activities and has the advantage of not depending on a subjective rating of an individual person. We further assessed functional capacity by both neuropsychological tests (including measures of attention, memory, working memory, executive functions, language, and depression). We also evaluated performance in finger tapping, grip strength, stride length, gait speed, and chair stands separately and while performing VR-DOTs in order to correlate performance in these measures with VR-DOTs because performance while navigating a virtual environment is a valid and reliable indicator of cognitive decline in elderly persons. The mild AD group was more impaired than the amnestic MCI group, and both were more impaired than healthy controls. The novel VR-DOT functional index correlated strongly with standard cognitive and functional measurements, such as mini-mental state examination (MMSE; rho=0.26, P=.01) and Bristol Activities of Daily Living (ADL) scale scores (rho=0.32, P=.001). Functional impairment is a defining characteristic of predementia and is partly dependent on the degree of cognitive impairment. The novel virtual reality measures of functional ability seem more sensitive to functional impairment than qualitative measures in predementia, thus accurately differentiating from healthy controls. We conclude that VR-DOT is an effective tool for discriminating predementia and mild AD from controls by detecting differences in terms of errors, omissions, and perseverations while measuring ADL functional ability.

Drug resistant Mycobacterium tuberculosis in Mexico.

PubMed

Zazueta-Beltran, Jorge; León-Sicairos, Claudia; Canizalez-Roman, Adrián

2009-04-30

Tuberculosis (TB) remains a serious public health problem, worsened by an increased frequency of multidrug-resistant (MDR) Mycobacterium tuberculosis strains. The World Health Organization (WHO) and the International Union Against Tuberculosis and Lung Disease (IUATLD) launched the Global Project on Anti-Tuberculosis Drug Resistance Surveillance to measure the prevalence of drug resistance. Data from the global reports on resistance to anti-tuberculosis (anti-TB) drugs have shown that drug resistance still presents worldwide and that MDR-TB is present in almost all the world. Though the Global Project (WHO) has been operating since 1994, very few countries and states have reported new information. Data from repeated surveys employing comparable methodologies over several years are essential to determine with any certainty in which direction the prevalence of drug resistance is moving. Drug-resistant tuberculosis and MDR-TB have been identified in Mexico, even with the existence of a National Tuberculosis Program based on Directly Observed Treatment, Short-course (DOTS). This review discusses available surveillance data on drug susceptibility data for TB in different states of Mexico.

Macro-kinetic investigation on phenol uptake from air by biofiltration: Influence of superficial gas flow rate and inlet pollutant concentration

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

Zilli, M.; Fabiano, B.; Ferraiolo, A.

1996-02-20

The macro-kinetic behavior of phenol removal from a synthetic exhaust gas was investigated theoretically as well as experimentally by means of two identical continuously operating laboratory-scale biological filter bed columns. A mixture of peat and glass beads was used as filter material. After sterilization it was inoculated with a pure strain of Pseudomonas putida, as employed in previous experimental studies. To determine the influence of the superficial gas flow rate on biofilter performance and to evaluate the phenol concentration profiles along the column, two series of continuous tests were carried out varying either the inlet phenol concentration, up to 1,650more » mg {center_dot} m{sup {minus}3}, or the superficial gas flow rate, from 30 to 460 m{sup 3} {center_dot} m{sup {minus}2} {center_dot} h{sup {minus}1}. The elimination capacity of the biofilter is proved by a maximum volumetric phenol removal rate of 0.73 kg {center_dot} m{sup {minus}3} {center_dot} h{sup {minus}1}. The experimental results are consistent with a biofilm model incorporating first-order substrate elimination kinetics. The model may be considered a useful tool in scaling-up a biofiltration system. Furthermore, the deodorization capacity of the biofilter was investigated, at inlet phenol concentrations up to 280 mg {center_dot} m{sup {minus}3} and superficial gas flow rates ranging from 30 to 92 m{sup 3} {center_dot} m{sup {minus}2} {center_dot} h{sup {minus}1}. The deodorization of the gas was achieved at a maximum inlet phenol concentration of about 255 mg {center_dot} m{sup {minus}3}, operating at a superficial gas flow rate of 30 m{sup 3} {center_dot} m{sup {minus}2} {center_dot} h{sup {minus}1}.« less

Simultaneous Quantitative Detection of Helicobacter Pylori Based on a Rapid and Sensitive Testing Platform using Quantum Dots-Labeled Immunochromatiographic Test Strips

NASA Astrophysics Data System (ADS)

Zheng, Yu; Wang, Kan; Zhang, Jingjing; Qin, Weijian; Yan, Xinyu; Shen, Guangxia; Gao, Guo; Pan, Fei; Cui, Daxiang

2016-02-01

Quantum dots-labeled urea-enzyme antibody-based rapid immunochromatographic test strips have been developed as quantitative fluorescence point-of-care tests (POCTs) to detect helicobacter pylori. Presented in this study is a new test strip reader designed to run on tablet personal computers (PCs), which is portable for outdoor detection even without an alternating current (AC) power supply. A Wi-Fi module was integrated into the reader to improve its portability. Patient information was loaded by a barcode scanner, and an application designed to run on tablet PCs was developed to handle the acquired images. A vision algorithm called Kmeans was used for picture processing. Different concentrations of various human blood samples were tested to evaluate the stability and accuracy of the fabricated device. Results demonstrate that the reader can provide an easy, rapid, simultaneous, quantitative detection for helicobacter pylori. The proposed test strip reader has a lighter weight than existing detection readers, and it can run for long durations without an AC power supply, thus verifying that it possesses advantages for outdoor detection. Given its fast detection speed and high accuracy, the proposed reader combined with quantum dots-labeled test strips is suitable for POCTs and owns great potential in applications such as screening patients with infection of helicobacter pylori, etc. in near future.

Quantum dot-doped silica nanoparticles as probes for targeting of T-lymphocytes.

PubMed

Bottini, Massimo; D'Annibale, Federica; Magrini, Andrea; Cerignoli, Fabio; Arimura, Yutaka; Dawson, Marcia I; Bergamaschi, Enrico; Rosato, Nicola; Bergamaschi, Antonio; Mustelin, Tomas

2007-01-01

To enhance diagnostic or therapeutic efficacy, novel nanomaterials must be engineered to function in biologically relevant environments, be visible by conventional fluorescent microscopy, and have multivalent loading capacity for easy detection or effective drug delivery. Here we report the fabrication of silica nanoparticles doped with quantum dots and superficially functionalized with amino and phosphonate groups. The amino groups were acylated with a water-soluble biotin-labeling reagent. The biotinylated nanoparticles were subsequently decorated with neutravidin by exploiting the strong affinity between neutravidin and biotin. The resultant neutravidin-decorated fluorescent silica nanoparticles stably dispersed under physiological conditions, were visible by conventional optical and confocal fluorescent microscopy, and could be further functionalized with macromolecules, nucleic acids, and polymers. We also coated the surface of the nanoparticles with biotinylated mouse anti-human CD3 (alphaCD3). The resultant fluorescent nanoassembly was taken up by Jurkat T cells through receptor-mediated endocytosis and was partially released to lysosomes. Thus, quantum dot-doped silica nanoparticles decorated with neutravidin represent a potentially excellent scaffold for constructing specific intracellular nanoprobes and transporters.

Molecular profiling of single cancer cells and clinical tissue specimens with semiconductor quantum dots

PubMed Central

Xing, Yun; Smith, Andrew M; Agrawal, Amit; Ruan, Gang; Nie, Shuming

2006-01-01

Semiconductor quantum dots (QDs) are a new class of fluorescent labels with broad applications in biomedical imaging, disease diagnostics, and molecular and cell biology. In comparison with organic dyes and fluorescent proteins, quantum dots have unique optical and electronic properties such as size-tunable light emission, improved signal brightness, resistance against photobleaching, and simultaneous excitation of multiple fluorescence colors. Recent advances have led to multifunctional nanoparticle probes that are highly bright and stable under complex in vitro and in vivo conditions. New designs involve encapsulating luminescent QDs with amphiphilic block copolymers, and linking the polymer coating to tumor-targeting ligands and drug-delivery functionalities. These improved QDs have opened new possibilities for real-time imaging and tracking of molecular targets in living cells, for multiplexed analysis of biomolecular markers in clinical tissue specimens, and for ultrasensitive imaging of malignant tumors in living animal models. In this article, we briefly discuss recent developments in bioaffinity QD probes and their applications in molecular profiling of individual cancer cells and clinical tissue specimens. PMID:17722280

Antiemetics With Concomitant Sedative Use in Civil Aviation Pilot Fatalities: From 2000 to 2006

DTIC Science & Technology

2007-10-01

Unclassified Unclassified 13 Form DOT F 1700.7 (8-72) Reproduction of completed page authorized iii CONTENTS INTRODUCTION...sedative hypnotics , and ethanol. Antiemetics and drugs with antiemetic properties such as metoclopramide, diphenhydramine (a sedating...antihistamines, ethanol, barbiturates, serotonin modulators, and/or sedative- hypnotics . Antihistamines such as diphenhydramine are commonly used. The

Effect of injection routes on the biodistribution, clearance, and tumor uptake of carbon dots.

PubMed

Huang, Xinglu; Zhang, Fan; Zhu, Lei; Choi, Ki Young; Guo, Ning; Guo, Jinxia; Tackett, Kenneth; Anilkumar, Parambath; Liu, Gang; Quan, Qimeng; Choi, Hak Soo; Niu, Gang; Sun, Ya-Ping; Lee, Seulki; Chen, Xiaoyuan

2013-07-23

The emergence of photoluminescent carbon-based nanomaterials has shown exciting potential in the development of benign nanoprobes. However, the in vivo kinetic behaviors of these particles that are necessary for clinical translation are poorly understood to date. In this study, fluorescent carbon dots (C-dots) were synthesized and the effect of three injection routes on their fate in vivo was explored by using both near-infrared fluorescence and positron emission tomography imaging techniques. We found that C-dots are efficiently and rapidly excreted from the body after all three injection routes. The clearance rate of C-dots is ranked as intravenous > intramuscular > subcutaneous. The particles had relatively low retention in the reticuloendothelial system and showed high tumor-to-background contrast. Furthermore, different injection routes also resulted in different blood clearance patterns and tumor uptakes of C-dots. These results satisfy the need for clinical translation and should promote efforts to further investigate the possibility of using carbon-based nanoprobes in a clinical setting. More broadly, we provide a testing blueprint for in vivo behavior of nanoplatforms under various injection routes, an important step forward toward safety and efficacy analysis of nanoparticles.

A Quick and Parallel Analytical Method Based on Quantum Dots Labeling for ToRCH-Related Antibodies

NASA Astrophysics Data System (ADS)

Yang, Hao; Guo, Qing; He, Rong; Li, Ding; Zhang, Xueqing; Bao, Chenchen; Hu, Hengyao; Cui, Daxiang

2009-12-01

Quantum dot is a special kind of nanomaterial composed of periodic groups of II-VI, III-V or IV-VI materials. Their high quantum yield, broad absorption with narrow photoluminescence spectra and high resistance to photobleaching, make them become a promising labeling substance in biological analysis. Here, we report a quick and parallel analytical method based on quantum dots for ToRCH-related antibodies including Toxoplasma gondii, Rubella virus, Cytomegalovirus and Herpes simplex virus type 1 (HSV1) and 2 (HSV2). Firstly, we fabricated the microarrays with the five kinds of ToRCH-related antigens and used CdTe quantum dots to label secondary antibody and then analyzed 100 specimens of randomly selected clinical sera from obstetric outpatients. The currently prevalent enzyme-linked immunosorbent assay (ELISA) kits were considered as “golden standard” for comparison. The results show that the quantum dots labeling-based ToRCH microarrays have comparable sensitivity and specificity with ELISA. Besides, the microarrays hold distinct advantages over ELISA test format in detection time, cost, operation and signal stability. Validated by the clinical assay, our quantum dots-based ToRCH microarrays have great potential in the detection of ToRCH-related pathogens.

Magnetoresistance engineering and singlet/triplet switching in InAs nanowire quantum dots with ferromagnetic sidegates

NASA Astrophysics Data System (ADS)

Fábián, G.; Makk, P.; Madsen, M. H.; Nygârd, J.; Schönenberger, C.; Baumgartner, A.

2016-11-01

We present magnetoresistance (MR) experiments on an InAs nanowire quantum dot device with two ferromagnetic sidegates (FSGs) in a split-gate geometry. The wire segment can be electrically tuned to a single dot or to a double dot regime using the FSGs and a backgate. In both regimes we find a strong MR and a sharp MR switching of up to 25% at the field at which the magnetizations of the FSGs are inverted by the external field. The sign and amplitude of the MR and the MR switching can both be tuned electrically by the FSGs. In a double dot regime close to pinch-off we find two sharp transitions in the conductance, reminiscent of tunneling MR (TMR) between two ferromagnetic contacts, with one transition near zero and one at the FSG switching fields. These surprisingly rich characteristics we explain in several simple resonant tunneling models. For example, the TMR-like MR can be understood as a stray-field controlled transitions between singlet and triplet double dot states. Such local magnetic fields are the key elements in various proposals to engineer novel states of matter and may be used for testing electron spin based Bell inequalities.

Improving Conflict Alert Performance Using Moving Target Detector Data.

DTIC Science & Technology

1982-06-01

2 L136 IIIII I lIlS 1 1 10 11120 125 11111I ~1.6 MICROCOPY RESOLUTION TEST CHART NATIONAL BUREAU Of SIANDARDg 19bi A DOT/FAA/RD-82/47 DOT/FAA/CT-81...Differences for Stochastic Case 23 7 Illustration of Scenarios for Warning Time Tests 30 8 Illustration of Scenarios Used for Nuisance Alert 35 Area...Nuisance Alert Area Analysis of Scenario 3 with a Target 64 Velocity of 480 Knots and SPMB= SPPB =2.8 nmi 12 Nuisance Alert Area Analysis of Scenario 3

A tunable digital ishihara plate for pre-school aged children.

PubMed

Gambino, Orazio; Minafo, Ester; Pirrone, Roberto; Ardizzone, Edoardo

2016-08-01

Colors play a fundamental role for children, both in the everyday life and in education. They recognize the surrounding world, and play games making a large use of colors. They learn letters and numbers by means of colors. As a consequence, early diagnosis of color blindness is an crucial to support an individual affected by this visual perception alteration at the initial phase of his/her life. The diagnosis of red-green color deficiencies (protanopia or deuteranopia) is commonly accomplished by means of the Ishihara test, which consists of plates showing dots with different sizes where some of them compose numbers within a gamut of colors while the ones composing the background have different colors. In this paper, a web application written in javascript is presented, that implements a digital Ishihara-like test for pre-school aged children. Instead numbers or letters, It can transform any binary image representing animal shapes, or any other child-friendly shape, into an Ishihara-like image. This digital plate is not static. The operator can increment the dot density to improve the quality of the shape contour and the entire plate can be redrawn with different dot sizes/colors chosen randomly according to the color pattern of the test. Separate controls for brightness and saturation are implemented to calibrate the chromatic aspect of the background and foreground dots.

Attentional bias to threat in the general population is contingent on target competition, not on attentional control settings.

PubMed

Wirth, Benedikt Emanuel; Wentura, Dirk

2018-04-01

Dot-probe studies usually find an attentional bias towards threatening stimuli only in anxious participants. Here, we investigated under what conditions such a bias occurs in unselected samples. According to contingent-capture theory, an irrelevant cue only captures attention if it matches an attentional control setting. Therefore, we first tested the hypothesis that an attentional control setting tuned to threat must be activated in (non-anxious) individuals. In Experiment 1, we used a dot-probe task with a manipulation of attentional control settings ('threat' - set vs. control set). Surprisingly, we found an (anxiety-independent) attentional bias to angry faces that was not moderated by attentional control settings. Since we presented two stimuli (i.e., a target and a distractor) on the target screen in Experiment 1 (a necessity to realise the test of contingent capture), but most dot-probe studies only employ a single target, we conducted Experiment 2 to test the hypothesis that attentional bias in the general population is contingent on target competition. Participants performed a dot-probe task, involving presentation of a stand-alone target or a target competing with a distractor. We found an (anxiety-independent) attentional bias towards angry faces in the latter but not the former condition. This suggests that attentional bias towards angry faces in unselected samples is not contingent on attentional control settings but on target competition.

The innovative moving bed biofilm reactor/solids contact reaeration process for secondary treatment of municipal wastewater

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

Rusten, B.; McCoy, M.; Proctor, R.

1998-07-01

The innovative moving bed biofilm reactor/solids contact reaeration (MBBR/SCR) process has been chosen for a new wastewater treatment plant serving a population of 200,000 at Moa Point, Wellington, New Zealand. Because the MBBR/SCR combination was new, a pilot-scale demonstration project was made part of the contract. Thorough pilot tests using a wide range of organic loads under both steady and transient-flow conditions demonstrated that the MBBR/SCR process produced the required effluent quality at loads higher than used in the original design. At 3 days mean cell residence time (MCRT) in the SCR stage, a final effluent with a 5-day biochemicalmore » oxygen demand (BOD{sub 5}) of less than 10 mg/L was achieved at an organic load on the MBBR of 15 g BOD{sub 5}/m{sup 2}{center_dot}d (5.0 kg BOD{sub 5}/m{sup 3}{center_dot}d). With the same MCRT, a final effluent of less than 15 mg BOD{sub 5}/L was achieved at an organic load on the MBBR of 20 g BOD{sub 5}/m{sup 2}{center_dot}d (6.7 kg BOD{sub 5}/m{sup 3}{center_dot}d). Dynamic loading tests demonstrated that a good-quality effluent was produced with a diurnal peak-hour load on the MBBR of more than 40 g BOD{sub 5}/m{sup 2}{center_dot}d (13.3 kg BOD{sub 5}/m{sup 3}{center_dot}d). The MBBR/SCR process was more compact and significantly cheaper than a conventional trickling filter/solids contact or activated-sludge process at the Moa Point site.« less

Detection of toxoplasma-specific immunoglobulin G in human sera: performance comparison of in house Dot-ELISA with ECLIA and ELISA.

PubMed

Teimouri, Aref; Modarressi, Mohammad Hossein; Shojaee, Saeedeh; Mohebali, Mehdi; Zouei, Nima; Rezaian, Mostafa; Keshavarz, Hossein

2018-05-08

In the current study, performance of electrochemiluminescence immunoassay (ECLIA) in detection of anti-toxoplasma IgG in human sera was compared with that of enzyme-linked immunosorbent assay (ELISA). Furthermore, performance of an in house Dot-ELISA in detection of anti-toxoplasma IgG was compared with that of ECLIA and ELISA. In total, 219 human sera were tested to detect anti-toxoplasma IgG using Dynex DS2® and Roche Cobas® e411 Automated Analyzers. Discordant results rechecked using immunofluorescence assay (IFA). Then, sera were used in an in house Dot-ELISA to assess toxoplasma-specific IgG. Of the 219 samples, two samples were found undetermined using ECLIA but reactive using ELISA. Using IFA, the two sera were reported unreactive. Furthermore, two samples were found reactive using ECLIA and unreactive using ELISA. These samples were reported reactive using IFA. The overall agreement for the two former methods was 98% (rZ0.98.1; P < 0.001). The intrinsic parameters calculated for in house Dot-ELISA included sensitivity of 79.5, specificity of 78.2, and accuracy of 78.9%, compared to ECLIA and ELISA. Positive and negative predictive values included 82.9 and 74.2%, respectively. A 100% sensitivity was found in in house Dot-ELISA for highly reactive sera in ECLIA and ELISA. ECLIA is appropriate for the first-line serological screening tests and can replace ELISA due to high speed, sensitivity, and specificity, particularly in large laboratories. Dot-ELISA is a rapid, sensitive, specific, cost-effective, user-friendly, and field-portable technique and hence can be used for screening toxoplasmosis, especially in rural fields or less equipped laboratories.

Delta One T Cells for Immunotherapy of Chronic Lymphocytic Leukemia: Clinical-Grade Expansion/Differentiation and Preclinical Proof of Concept.

PubMed

Almeida, Afonso R; Correia, Daniel V; Fernandes-Platzgummer, Ana; da Silva, Cláudia L; da Silva, Maria Gomes; Anjos, Diogo Remechido; Silva-Santos, Bruno

2016-12-01

The Vδ1 + subset of γδ T lymphocytes is a promising candidate for cancer immunotherapy, but the lack of suitable expansion/differentiation methods has precluded therapeutic application. We set out to develop and test (preclinically) a Vδ1 + T-cell-based protocol that is good manufacturing practice compatible and devoid of feeder cells for prompt clinical translation. We tested multiple combinations of clinical-grade agonist antibodies and cytokines for their capacity to expand and differentiate (more than 2-3 weeks) Vδ1 + T cells from the peripheral blood of healthy donors and patients with chronic lymphocytic leukemia (CLL). We characterized the phenotype and functional potential of the final cellular product, termed Delta One T (DOT) cells, in vitro and in vivo (xenograft models of CLL). We describe a very robust two-step protocol for the selective expansion (up to 2,000-fold in large clinical-grade cell culture bags) and differentiation of cytotoxic Vδ1 + (DOT) cells. These expressed the natural cytotoxicity receptors, NKp30 and NKp44, which synergized with the T-cell receptor to mediate leukemia cell targeting in vitro When transferred in vivo, DOT cells infiltrated tumors and peripheral organs, and persisted until the end of the analysis without showing signs of loss of function; indeed, DOT cells proliferated and produced abundant IFNγ and TNFα, but importantly no IL17, in vivo Critically, DOT cells were capable of inhibiting tumor growth and preventing dissemination in xenograft models of CLL. We provide a clinical-grade method and the preclinical proof of principle for application of a new cellular product, DOT cells, in adoptive immunotherapy of CLL. Clin Cancer Res; 22(23); 5795-804. ©2016 AACR. ©2016 American Association for Cancer Research.

Role of Nanoparticles in Drug Delivery and Regenerative Therapy for Bone Diseases.

PubMed

Gera, Sonia; Sampathi, Sunitha; Dodoala, Sujatha

2017-01-01

Osteoporosis is a disease characterized by progressive bone loss due to aging and menopause in women leading to bone fragility with increased susceptibility towards fractures. The silent disease weakens the bone by altering its microstructure and mass. Therapy is based on either promoting strength (via osteoblast action) or preventing disease (via osteoclast action). Current therapy with different drugs belonging to antiresorptive, anabolic and hormonal classification suffers from poor pharmacokinetic and pharmacodynamic profile. Nanoparticles provide breakthrough as an alternative therapeutic carrier and biomedical imaging tool in bone diseases. The current review highlights bone physiology and pathology along with potential applications of nanoparticles in osteoporosis through use of organic and inorganic particles for drug delivery, biomedical imaging as well as bone tissue regeneration therapy. Inorganic nanoparticles of gold, cerium, platinum and silica have effects on osteoblastic and osteoclastic lineage. Labelling and tracking of bone cells by quantum dots and gold nanoparticles are advanced and non-invasive techniques. Incorporation of nanoparticles into the scaffolds is a more recent technique for improving mechanical strength as well as regeneration during bone grafting. Promising results by in vitro and in vivo studies depicts effects of nanoparticles on biochemical markers and biomechanical parameters during osteoporosis suggesting the bright future of nanoparticles in bone applications. Any therapy which improves the drug profile and delivery to bone tissue will be promising approach. Superparamagnetic, gold, mesoporous silica nanoparticles and quantum dots provide golden opportunities for biomedical imaging by replacing the traditional invasive radionuclide techniques. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Acute Effects of 30 Minutes Resistance and Aerobic Exercise on Cognition in a High School Sample.

PubMed

Harveson, Andrew T; Hannon, James C; Brusseau, Timothy A; Podlog, Leslie; Papadopoulos, Charilaos; Durrant, Lynne H; Hall, Morgan S; Kang, Kyoung-Doo

2016-06-01

The purpose of this study was to determine differences in cognition between acute bouts of resistance exercise, aerobic exercise, and a nonexercise control in an untrained youth sample. Ninety-four participants performed 30 min of aerobic exercise, resistance exercise, or nonexercise separated by 7 days each in a randomized crossover design. After each exercise intervention, participants were assessed using 2 cognitive tests. The Dot, Word, and Color elements of the Stroop Test (Victoria version) and Parts A and B of the Trail-Making Test were used to measure cognition. Acute resistance and aerobic exercise resulted in similar improvements over nonexercise in all forms of the Stroop Test. Acute aerobic exercise led to improved performance over nonexercise and resistance exercise in Part B of the Trail-Making Test. Neither exercise intervention showed significant changes in time to complete Part A of the Trail-Making Test. Boys outperformed girls on the Stroop Dot and Color Test following acute aerobic exercise, in the Stroop Dot, Word, and Color Test following acute resistance exercise, and in the Stroop Color Test and Trail-Making Test Part B following nonexercise. Both acute resistance and aerobic exercise increased measures of cognition over a nonexercise control in untrained high school youth. These findings suggest the merits of acute resistance exercise as an alternative or complement to aerobic activity for educators aiming to increase youth physical activity and cognitive function concurrently.

Physical and mechanical properties and fire, decay, and termite resistance of treated oriented strandboard

Treesearch

Nadir Ayrilmis; S Nami Kartal; Theodore L. Laufenberg; Jerrold E. Winandy; Robert H. White

2005-01-01

This study evaluated the effects of a number of chemicals on the physical and mechanical properties and fire, decay, and termite resistance of oriented strandboard (OSB) panels. Disodium octaborate tetrahydrate (DOT), boric acid (BA), melamine phosphate (MP), and a BA/DOT mixture were sprayed onto the furnish at varying concentrations. The panels were tested for...

49 CFR 40.213 - What training requirements must STTs and BATs meet?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false What training requirements must STTs and BATs meet... requirements must STTs and BATs meet? To be permitted to act as a BAT or STT in the DOT alcohol testing program...). (1) Qualification training must be in accordance with the DOT Model BAT or STT Course, as applicable...

49 CFR 40.213 - What training requirements must STTs and BATs meet?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 1 2012-10-01 2012-10-01 false What training requirements must STTs and BATs meet... requirements must STTs and BATs meet? To be permitted to act as a BAT or STT in the DOT alcohol testing program...). (1) Qualification training must be in accordance with the DOT Model BAT or STT Course, as applicable...

49 CFR 40.213 - What training requirements must STTs and BATs meet?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 1 2011-10-01 2011-10-01 false What training requirements must STTs and BATs meet... requirements must STTs and BATs meet? To be permitted to act as a BAT or STT in the DOT alcohol testing program...). (1) Qualification training must be in accordance with the DOT Model BAT or STT Course, as applicable...

49 CFR 40.213 - What training requirements must STTs and BATs meet?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 1 2013-10-01 2013-10-01 false What training requirements must STTs and BATs meet... requirements must STTs and BATs meet? To be permitted to act as a BAT or STT in the DOT alcohol testing program...). (1) Qualification training must be in accordance with the DOT Model BAT or STT Course, as applicable...

49 CFR 40.213 - What training requirements must STTs and BATs meet?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 1 2014-10-01 2014-10-01 false What training requirements must STTs and BATs meet... requirements must STTs and BATs meet? To be permitted to act as a BAT or STT in the DOT alcohol testing program...). (1) Qualification training must be in accordance with the DOT Model BAT or STT Course, as applicable...

[GM1-dot-EIA for the detection of toxin-producing Vibrio cholerae strains].

PubMed

Markina, O V; Alekseeva, L P; Telesmanich, N R; Chemisova, O S; Akulova, M V; Markin, N V

2011-05-01

A new variant of enzyme immunoassay (EIA) has been developed on the basis of GM1 gangliosides to detect the toxin-producing Vibrio cholerae strains--GM1-dot-EIA. Experiments were run using a nitrocellulose membrane to bind GM1 gangliosides and polyclonal antitoxic serum to detect cholerogen. GM1-dot-EIA testing identified cholera toxin in 11 of 13 supernatants of V. cholerae eltor ctx(+) strains isolated from man and in 3 of 7 supernatants of V. cholerae eltor ctx(+) strains isolated from water. These data agree with those obtained in CM1-EIA. There was no reaction with the supernatants of other microorganisms. The sensitivity of the technique was 10 ng/ml. Thus, the simple and specific GM1-dot-EIA may be recommended to detect toxin-producing V cholerae strains isolated from man and water.

Videogrammetry Using Projected Circular Targets: Proof-of-Concept Test

NASA Technical Reports Server (NTRS)

Pappa, Richard S.; Black, Jonathan T.

2003-01-01

Videogrammetry is the science of calculating 3D object coordinates as a function of time from image sequences. It expands the method of photogrammetry to multiple time steps enabling the object to be characterized dynamically. Photogrammetry achieves the greatest accuracy with high contrast, solid-colored, circular targets. The high contrast is most often effected using retro-reflective targets attached to the measurement article. Knowledge of the location of each target allows those points to be tracked in a sequence of images, thus yielding dynamic characterization of the overall object. For ultra-lightweight and inflatable gossamer structures (e.g. solar sails, inflatable antennae, sun shields, etc.) where it may be desirable to avoid physically attaching retro-targets, a high-density grid of projected circular targets - called dot projection - is a viable alternative. Over time the object changes shape or position independently of the dots. Dynamic behavior, such as deployment or vibration, can be characterized by tracking the overall 3D shape of the object instead of tracking specific object points. To develop this method, an oscillating rigid object was measured using both retroreflective targets and dot projection. This paper details these tests, compares the results, and discusses the overall accuracy of dot projection videogrammetry.

Videogrammetry Using Projected Circular Targets: Proof-of-Concept Test

NASA Technical Reports Server (NTRS)

Black, Jonathan T.; Pappa, Richard S.

2003-01-01

Videogrammetry is the science of calculating 3D object coordinates as a function of time from image sequences. It expands the method of photogrammetry to multiple time steps enabling the object to be characterized dynamically. Photogrammetry achieves the greatest accuracy with high contrast, solid-colored circular targets. The high contrast is most often effected using retro-reflective targets attached to the measurement article. Knowledge of the location of each target allows those points to be tracked in a sequence of images, thus yielding dynamic characterization of the overall object. For ultra-lightweight and inflatable gossamer structures (e.g. solar sails, inflatable antennae, sun shields, etc.) where it may be desirable to avoid physically attaching retro-targets, a high-density grid of projected circular targets - called dot projection - is a viable alternative. Over time the object changes shape or position independently of the dots. Dynamic behavior, such as deployment or vibration, can be characterized by tracking the overall 3D shape of the object instead of tracking specific object points. To develop this method, an oscillating rigid object was measured using both retro- reflective targets and dot projection. This paper details these tests, compares the results, and discusses the overall accuracy of dot projection videogrammetry.

Conductive polymer nanotube patch for fast and controlled in vivo transdermal drug delivery

NASA Astrophysics Data System (ADS)

Nguyen, Thao M.

Transdermal drug delivery has created new applications for existing therapies and offered an alternative to the traditional oral route where drugs can prematurely metabolize in the liver causing adverse side effects. Opening the transdermal delivery route to large hydrophilic drugs is one of the greatest challenges due to the hydrophobicity of the skin. However, the ability to deliver hydrophilic drugs using a transdermal patch would provide a solution to problems of other delivery methods for hydrophilic drugs. The switching of conductive polymers (CP) between redox states cause simultaneous changes in the polymer charge, conductivity, and volume—properties that can all be exploited in the biomedical field of controlled drug delivery. Using the template synthesis method, poly(3,4-ethylenedioxythiophene (PEDOT) nanotubes were synthesized electrochemically and a transdermal drug delivery patch was successfully designed and developed. In vitro and in vivo uptake and release of hydrophilic drugs were investigated. The relationship between the strength of the applied potential and rate of drug release were also investigated. Results revealed that the strength of the applied potential is proportional to the rate of drug release; therefore one can control the rate of drug release by controlling the applied potential. The in vitro studies focused on the kinetics of the drug delivery system. It was determined that the drug released mainly followed zero-order kinetics. In addition, it was determined that applying a releasing potential to the transdermal drug delivery system lead to a higher release rate constant (up to 7 times greater) over an extended period of time (˜24h). In addition, over 24 hours, an average of 80% more model drug molecules were released with an applied potential than without. The in vivo study showed that the drug delivery system was capable of delivering model hydrophilic drugs molecules through the dermis layer of the skin within 30 minutes, while the control showed no visible drugs at the same depth. Most importantly, it was determined that the delivery of drugs into the blood stream was stable within 20 minutes. The functionalization of CP was also studied in order to enhance the properties and drug loading capabilities of the polymers. The co-polymerization of poly(3,4-(2-methylene)propylenedioxythiophene) (PMProDot) with polystyrene (PS) and polyvinylcarbazole (PVK) through the highly reactive methylene group was achieved. The modified PMProDot nanotubes demonstrated response times that were two times faster than without modification. The modification of PEDOT nanotubes with polydopamine, a biocompatible polymer, was also investigated and achieved. In depth characterization of functionalized CP demonstrate the ability to fine tune the properties of the polymer in order to achieve the required therapeutic drug release profile.

Rapid detection of rifampin-resistant clinical isolates of Mycobacterium tuberculosis by reverse dot blot hybridization.

PubMed

Guo, Qian; Yu, Yan; Zhu, Yan Ling; Zhao, Xiu Qin; Liu, Zhi Guang; Zhang, Yuan Yuan; Li, Gui Lian; Wei, Jian Hao; Wu, Yi Mou; Wan, Kang Lin

2015-01-01

A PCR-reverse dot blot hybridization (RDBH) assay was developed for rapid detection of rpoB gene mutations in 'hot mutation region' of Mycobacterium tuberculosis (M. tuberculosis). 12 oligonucleotide probes based on the wild-type and mutant genotype rpoB sequences of M. tuberculosis were designed to screen the most frequent wild-type and mutant genotypes for diagnosing RIF resistance. 300 M. tuberculosis clinical isolates were detected by RDBH, conventional drug-susceptibility testing (DST) and DNA sequencing to evaluate the RDBH assay. The sensitivity and specificity of the RDBH assay were 91.2% (165/181) and 98.3% (117/119), respectively, as compared to DST. When compared with DNA sequencing, the accuracy, positive predictive value (PPV) and negative predictive value (NPV) of the RDBH assay were 97.7% (293/300), 98.2% (164/167), and 97.0% (129/133), respectively. Furthermore, the results indicated that the most common mutations were in codons 531 (48.6%), 526 (25.4%), 516 (8.8%), and 511 (6.6%), and the combinative mutation rate was 15 (8.3%). One and two strains of insertion and deletion were found among all strains, respectively. Our findings demonstrate that the RDBH assay is a rapid, simple and sensitive method for diagnosing RIF-resistant tuberculosis. Copyright © 2015 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

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.

WISE-2005: LBNP/Treadmill and Resistive Exercise Countermeasures Maintain Aerobic Capacity during a 60-d Bed Rest

NASA Technical Reports Server (NTRS)

Schneider, Suzanne M.; Lee, Stuart M. C.; Watenpaugh, Donald E.; Macias, Brandon R.; Hargens, Alan R.

2006-01-01

We have previously documented that supine treadmill exercise within lower body negative pressure (LBNPex) performed 6 sessions (raised dot) wk(sup -1) during 15- and 30-day bed rests (BR) maintained upright aerobic capacity (VO2pk). In the present study, ure are evaluating whether aerobic capacity is maintained during a 60-d BR when the LBNPex frequency is reduced to 2-4 sessions (raised dot) wk(sup -1) and resistance exercise (REX) is added 2-3 sessions (raised dot) wk(sup -1). Eight healthy women (32 plus or minus 4 yrs; 56.4 plus or minus 3.6 kg; 164 plus or minus 8 cm; mean plus or minus SD) performed maximal-exertion, graded treadmill tests before and 3 days after a 60-d, 6 deg. head-down tilt BR. (Earliest day the medical monitors would permit a maximal exercise test post-BR). During BR, four subjects performed no exercise (CON), while four other subjects (EX) performed LBNPex and REX on separate days. The LBNPex countermeasure employed an intermittent (40-80% pre-BR VO2pk), 40-min protocol against an LBNP pressure (-49 plus or minus 3 mmHg) applied to provide a footward force equivalent to 1.0-1.2 body weight. REX consisted of maximal concentric and eccentric supine leg press and heel raise exercises using a gravity-independent flywheel ergometer. Comparisons were performed using paired (within-group) or non-paired (between-group) t-tests. Three days post-BR, VO2pk of the CON group was reduced significantly from pre-BR (Pre:37.2 plus or minus 1.2, Post: 29.4 plus or minus 2 ml (raised dot) kg(sup -1) (raised dot) min(sup -1), P less than 0.05), while the VO2pk of the EX group was not significantly reduced (Pre: 39.6 plus or minus 1.9, Post: 38.0 plus or minus 0.6 ml (raised dot) kg(sup -1) (raised dot) min(sup -1)). Peak heart rate, ventilation, rating of perceived exertion, and respiratory exchange ratio were not significantly different between the two groups pre- and post-BR. These preliminary results suggest that the combined LBNPex and REX countermeasures may be sufficient to maintain upright aerobic capacity after long-duration space flights.

Stereopsis testing without polarized glasses: a comparison study on five new stereoacuity tests.

PubMed

Hatch, S W; Richman, J E

1994-09-01

Stereopsis testing is commonly used to assess the presence and level of binocular vision. A new series of stereopsis tests requiring no polarized goggles are available in the form of the Titmus Stereo Test, the Stereo Reindeer Test, the Random Dot Butterfly, the Random Dot Figures, and the Random E, Circle, Square. These polarized-free tests employ a special prismatic printing process creating a panagraphic presentation, i.e., a separate image is presented to each eye without the need for polarization. The purpose of this study was to compare the polarized-free stereo tests with their traditional polarized counterparts. Thirty four subjects, including several persons with strabismus, ages 10-35 years, were each tested with the polarized and polarized-free versions of the Titmus, Reindeer, Butterfly, and Figures. Twenty nine of these subjects were tested with the Random Dot E. Half the subjects were tested first with polarized-free and half were tested first with polarized tests. Tests were performed according to manufacturer instructions by the same examiner in clinical settings. The results (matched pair ranked correlation coefficients) indicate that the polarized-free tests were highly correlated (r = 0.997, r = 0.998, r = 0.997, r = 1.00, and r = 1.00 respectively) with the polarized comparison tests. No significant difference (Wilcoxon Ranked Sign) in the stereopsis level was obtained between the two versions of the tests. We conclude that these five polarized-free tests were just as valid in measuring the subjects' stereopsis as their traditional polarized version. The use of goggle-free testing has potential clinical advantages, e.g., testing of young children who will not wear the glasses or the improved observation of the ocular alignment during stereopsis testing.

Numerical Simulations of Gaseous Disks Generated from Collisional Cascades at the Roche Limits of White Dwarf Stars

NASA Astrophysics Data System (ADS)

Kenyon, Scott J.; Bromley, Benjamin C.

2017-11-01

We consider the long-term evolution of gaseous disks fed by the vaporization of small particles produced in a collisional cascade inside the Roche limit of a 0.6 {M}⊙ white dwarf. Adding solids with radius {r}0 at a constant rate {\\dot{M}}0 into a narrow annulus leads to two distinct types of evolution. When {\\dot{M}}0≳ {\\dot{M}}0,{crit}≈ 3× {10}4 {({r}0/1{km})}3.92 {{g}} {{{s}}}-1, the cascade generates a fairly steady accretion disk where the mass transfer rate of gas onto the white dwarf is roughly {\\dot{M}}0 and the mass in gas is {M}g≈ 2.3× {10}22 ({\\dot{M}}0/{10}10 {{g}} {{{s}}}-1) (1500 {{K}}/{T}0) ({10}-3/α ) g, where T 0 is the temperature of the gas near the Roche limit and α is the dimensionless viscosity parameter. If {\\dot{M}}0≲ {\\dot{M}}0,{crit}, the system alternates between high states with large mass transfer rates and low states with negligible accretion. Although either mode of evolution adds significant amounts of metals to the white dwarf photosphere, none of our calculations yield a vertically thin ensemble of solids inside the Roche limit. X-ray observations can place limits on the mass transfer rate and test this model for metallic line white dwarfs.

Assessment of Directly Observed Therapy (DOT) following tuberculosis regimen change in Addis Ababa, Ethiopia: a qualitative study.

PubMed

Fiseha, Daniel; Demissie, Meaza

2015-09-30

Tuberculosis remains a major public health problem in Ethiopia. In 2010 the TB treatment regimen was shortened from 8 to 6-months treatment. With this new regimen, the full course of treatment should be taken under Directly Observed Therapy (DOT) unlike the 8-month regimen where TB patients were only observed during the intensive phase, this has not been tried before and may be difficult to implement. Therefore this study aimed to investigate the experiences from both TB patients and health care providers' perspective of implementing DOT for the full course of TB treatment. Qualitative study consisted of 11 in-depth interviews and 4 Focus Group Discussions (FDGs) were conducted between March and April, 2014. Overall, 18 TB patients and 16 HCPs were involved from three selected public health facilities (2 Health Centers and 1 Hospital) in Addis Ababa, Ethiopia. Qualitative data analysis software (Open Code Version 3.5) was employed to identify the key issues from these interviews through coding, categorization and grouping into emergent themes. Participants reported that making a daily visit to health facilities for DOT was difficult due to the distance of the facilities from their residences, lack of or high transportation cost and had undesired implications on their work and social lives. TB patients had to overcome many challenges to comply with TB treatment on a daily basis. HCPs also indicated the difficulties of implementing facility based daily DOT mainly due the implication it had on their TB patients and stated DOT had not always been implemented for the full course as recommended. HCPs also shared deep concern regarding the risk of acquiring multiple drug resistant TB. This study indicated there are several challenges associated with facility based daily DOT as a method of TB treatment supervision in public health facilities in Addis Ababa. This may be indicative of the situation in other health facilities in Addis Ababa as well as elsewhere in the country. Hence the TB control program has to explore how best to improve TB treatment delivery options to ensure adequate treatment. A more patient-centered approach could be strengthened by further decentralizing the DOT to the community level in order to ensure adherence of patients to their TB treatment.

Cytotoxicity of metal and semiconductor nanoparticles indicated by cellular micromotility.

PubMed

Tarantola, Marco; Schneider, David; Sunnick, Eva; Adam, Holger; Pierrat, Sebastien; Rosman, Christina; Breus, Vladimir; Sönnichsen, Carsten; Basché, Thomas; Wegener, Joachim; Janshoff, Andreas

2009-01-27

In the growing field of nanotechnology, there is an urgent need to sensitively determine the toxicity of nanoparticles since many technical and medical applications are based on controlled exposure to particles, that is, as contrast agents or for drug delivery. Before the in vivo implementation, in vitro cell experiments are required to achieve a detailed knowledge of toxicity and biodegradation as a function of the nanoparticles' physical and chemical properties. In this study, we show that the micromotility of animal cells as monitored by electrical cell-substrate impedance analysis (ECIS) is highly suitable to quantify in vitro cytotoxicity of semiconductor quantum dots and gold nanorods. The method is validated by conventional cytotoxicity testing and accompanied by fluorescence and dark-field microscopy to visualize changes in the cytoskeleton integrity and to determine the location of the particles within the cell.

GPS Device Testing Based on User Performance Metrics

DOT National Transportation Integrated Search

2015-10-02

1. Rationale for a Test Program Based on User Performance Metrics ; 2. Roberson and Associates Test Program ; 3. Status of, and Revisions to, the Roberson and Associates Test Program ; 4. Comparison of Roberson and DOT/Volpe Programs

Mn/ROAD testing protocols : vol. 1

DOT National Transportation Integrated Search

1997-12-01

This report presents a series of testing protocols used at the Minnesota Road Research Project (Mn/ROAD), the Minnesota Department of Transportation's (Mn/DOT) pavement testing facility. This report helps establish a history of the tests conducted an...

Curcumin Quantum Dots Mediated Degradation of Bacterial Biofilms.

PubMed

Singh, Ashish K; Prakash, Pradyot; Singh, Ranjana; Nandy, Nabarun; Firdaus, Zeba; Bansal, Monika; Singh, Ranjan K; Srivastava, Anchal; Roy, Jagat K; Mishra, Brahmeshwar; Singh, Rakesh K

2017-01-01

Bacterial biofilm has been reported to be associated with more than 80% of bacterial infections. Curcumin, a hydrophobic polyphenol compound, has anti-quorum sensing activity apart from having antimicrobial action. However, its use is limited by its poor aqueous solubility and rapid degradation. In this study, we attempted to prepare quantum dots of the drug curcumin in order to achieve enhanced solubility and stability and investigated for its antimicrobial and antibiofilm activity. We utilized a newer two-step bottom up wet milling approach to prepare Curcumin Quantum Dots (CurQDs) using acetone as a primary solvent. Minimum inhibitory concentration against select Gram-positive and Gram-negative bacteria was performed. The antibiofilm assay was performed at first using 96-well tissue culture plate and subsequently validated by Confocal Laser Scanning Microscopy. Further, biofilm matrix protein was isolated using formaldehyde sludge and TCA/Acetone precipitation method. Protein extracted was incubated with varying concentration of CurQDs for 4 h and was subjected to SDS-PAGE. Molecular docking study was performed to observe interaction between curcumin and phenol soluble modulins as well as curli proteins. The biophysical evidences obtained from TEM, SEM, UV-VIS, fluorescence, Raman spectroscopy, and zeta potential analysis confirmed the formation of curcumin quantum dots with increased stability and solubility. The MICs of curcumin quantum dots, as observed against both select gram positive and negative bacterial isolates, was observed to be significantly lower than native curcumin particles. On TCP assay, Curcumin observed to be having antibiofilm as well as biofilm degrading activity. Results of SDS-PAGE and molecular docking have shown interaction between biofilm matrix proteins and curcumin. The results indicate that aqueous solubility and stability of Curcumin can be achieved by preparing its quantum dots. The study also demonstrates that by sizing down the particle size has not only enhanced its antimicrobial properties but it has also shown its antibiofilm activities. Further, study is needed to elucidate the exact nature of interaction between curcumin and biofilm matrix proteins.

Peptide-functionalized quantum dots for potential applications in the imaging and treatment of obesity.

PubMed

Thovhogi, Ntevheleni; Sibuyi, Nicole Remaliah Samantha; Onani, Martin Opiyo; Meyer, Mervin; Madiehe, Abram Madimabe

2018-01-01

Obesity is a worldwide epidemic affecting millions of people. The current pharmacological treatment of obesity remains limited and ineffective due to drugs' undesirable side effects. Hence, there is a need for novel or improved strategies for long-term therapies that will help prevent the disease progression into other chronic diseases. Nanotechnology holds the future for the treatment of obesity because of its versatility, as shown by improved drug efficiency and safety in cancer clinical trials. Nano-based drug delivery systems could potentially do the same for obesity through targeted drug delivery. This study investigated the use of peptide-functionalized quantum dots (QDs) for the imaging of prohibitin (PHB)-expressing cells in vitro and in diet-induced obese rats, which could potentially be used as nanocarriers of antiobesity drugs. Cadmium (Cd)-based QDs were functionalized with an adipose homing peptide (AHP) and injected intravenously into lean and obese Wistar rats. Biodistribution of the QDs was analyzed by an IVIS ® Lumina XR imaging system and inductively coupled plasma optical emission spectroscopy (ICP-OES). For in vitro studies, PHB-expressing (Caco-2 and MCF-7) and non-PHB-expressing (KMST-6 and CHO) cells were exposed to either unfunctionalized QDs (QD625) or AHP-functionalized QDs (AHP-QD625) and analyzed by fluorescence microscopy. AHP-QD625 accumulated significantly in PHB-expressing cells in vitro when compared with non-PHB-expressing cells. In vivo data indicated that QD625 accumulated mainly in the reticuloendothelial system (RES) organs, while the AHP-QD625 accumulated mostly in the white adipose tissues (WATs). AHP-functionalized QDs were successfully and selectively delivered to the PHB-expressing cells in vitro (Caco-2 and MCF-7 cells) and in the WAT vasculature in vivo. This nanotechnology-based approach could potentially be used for dual targeted drug delivery and molecular imaging of adipose tissues in obese patients in real time.

Radiated Emissions Test Approach

DOT National Transportation Integrated Search

2015-10-02

1. Draft Department of Transportation (DOT) Test Plan to Develop : Interference Tolerance Masks for GNSS Receivers in the L1 : Radiofrequency Band (1559 1610 MHz) provides high level : overview of radiated emissions test setup : 2. Presenta...

Cadmium-containing quantum dots: properties, applications, and toxicity.

PubMed

Mo, Dan; Hu, Liang; Zeng, Guangming; Chen, Guiqiu; Wan, Jia; Yu, Zhigang; Huang, Zhenzhen; He, Kai; Zhang, Chen; Cheng, Min

2017-04-01

The marriage of biology with nanomaterials has significantly accelerated advancement of biological techniques, profoundly facilitating practical applications in biomedical fields. With unique optical properties (e.g., tunable broad excitation, narrow emission spectra, robust photostability, and high quantum yield), fluorescent quantum dots (QDs) have been reasonably functionalized with controllable interfaces and extensively used as a new class of optical probe in biological researches. In this review, we summarize the recent progress in synthesis and properties of QDs. Moreover, we provide an overview of the outstanding potential of QDs for biomedical research and innovative methods of drug delivery. Specifically, the applications of QDs as novel fluorescent nanomaterials for biomedical sensing and imaging have been detailedly highlighted and discussed. In addition, recent concerns on potential toxicity of QDs are also introduced, ranging from cell researches to animal models.

Synthesis and characterization of graphene quantum dots-silver nanocomposites

NASA Astrophysics Data System (ADS)

Vandana, M.; Ashokkumar, S. P.; Vijeth, H.; Niranjana, M.; Yesappa, L.; Devendrappa, H.

2018-04-01

A facile microwave assisted hydrothermal method is used to synthesise glucose derived water soluble crystalline graphene quantum dots (GQDs) andcitrate reduction method was used to synthesized silver nanoparticles (SNPs). The formation of graphene quantum dots-silver nanocomposites (GSC) was synthesized through a simple refluxing process and characterised using Fourier Transform Infrared (FT-IR) to study the chemical interaction, Surface morphology using FESEM, Optical properties were studied using UV-Visible spectroscopy. The absorption band shows at 249, 306 and 447 nm confirms the formation of GQDs and GSC. The electrochemical performance of GSC tested to determine the oxidation/reduction processes by cyclic voltammetry and linear sweep voltammetry.

Differential computation method used to calibrate the angle-centroid relationship in coaxial reverse Hartmann test

NASA Astrophysics Data System (ADS)

Li, Xinji; Hui, Mei; Zhao, Zhu; Liu, Ming; Dong, Liquan; Kong, Lingqin; Zhao, Yuejin

2018-05-01

A differential computation method is presented to improve the precision of calibration for coaxial reverse Hartmann test (RHT). In the calibration, the accuracy of the distance measurement greatly influences the surface shape test, as demonstrated in the mathematical analyses. However, high-precision absolute distance measurement is difficult in the calibration. Thus, a differential computation method that only requires the relative distance was developed. In the proposed method, a liquid crystal display screen successively displayed two regular dot matrix patterns with different dot spacing. In a special case, images on the detector exhibited similar centroid distributions during the reflector translation. Thus, the critical value of the relative displacement distance and the centroid distributions of the dots on the detector were utilized to establish the relationship between the rays at certain angles and the detector coordinates. Experiments revealed the approximately linear behavior of the centroid variation with the relative displacement distance. With the differential computation method, we increased the precision of traditional calibration 10-5 rad root mean square. The precision of the RHT was increased by approximately 100 nm.

Location memory for dots in polygons versus cities in regions: evaluating the category adjustment model.

PubMed

Friedman, Alinda; Montello, Daniel R; Burte, Heather

2012-09-01

We conducted 3 experiments to examine the category adjustment model (Huttenlocher, Hedges, & Duncan, 1991) in circumstances in which the category boundaries were irregular schematized polygons made from outlines of maps. For the first time, accuracy was tested when only perceptual and/or existing long-term memory information about identical locations was cued. Participants from Alberta, Canada and California received 1 of 3 conditions: dots-only, in which a dot appeared within the polygon, and after a 4-s dynamic mask the empty polygon appeared and the participant indicated where the dot had been; dots-and-names, in which participants were told that the first polygon represented Alberta/California and that each dot was in the correct location for the city whose name appeared outside the polygon; and names-only, in which there was no first polygon, and participants clicked on the city locations from extant memory alone. Location recall in the dots-only and dots-and-names conditions did not differ from each other and had small but significant directional errors that pointed away from the centroids of the polygons. In contrast, the names-only condition had large and significant directional errors that pointed toward the centroids. Experiments 2 and 3 eliminated the distribution of stimuli and overall screen position as causal factors. The data suggest that in the "classic" category adjustment paradigm, it is difficult to determine a priori when Bayesian cue combination is applicable, making Bayesian analysis less useful as a theoretical approach to location estimation. PsycINFO Database Record (c) 2012 APA, all rights reserved.

A Single Mechanism Can Account for Human Perception of Depth in Mixed Correlation Random Dot Stereograms

PubMed Central

Cumming, Bruce G.

2016-01-01

In order to extract retinal disparity from a visual scene, the brain must match corresponding points in the left and right retinae. This computationally demanding task is known as the stereo correspondence problem. The initial stage of the solution to the correspondence problem is generally thought to consist of a correlation-based computation. However, recent work by Doi et al suggests that human observers can see depth in a class of stimuli where the mean binocular correlation is 0 (half-matched random dot stereograms). Half-matched random dot stereograms are made up of an equal number of correlated and anticorrelated dots, and the binocular energy model—a well-known model of V1 binocular complex cells—fails to signal disparity here. This has led to the proposition that a second, match-based computation must be extracting disparity in these stimuli. Here we show that a straightforward modification to the binocular energy model—adding a point output nonlinearity—is by itself sufficient to produce cells that are disparity-tuned to half-matched random dot stereograms. We then show that a simple decision model using this single mechanism can reproduce psychometric functions generated by human observers, including reduced performance to large disparities and rapidly updating dot patterns. The model makes predictions about how performance should change with dot size in half-matched stereograms and temporal alternation in correlation, which we test in human observers. We conclude that a single correlation-based computation, based directly on already-known properties of V1 neurons, can account for the literature on mixed correlation random dot stereograms. PMID:27196696

Xyloglucan oligosaccharides promote growth and activate cellulase: Evidence for a role of cellulase in cell expansion. [Pisum sativum L

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

McDougall, G.J.; Fry, S.C.

1990-07-01

Oligosaccharides produced by the action of fungal cellulase on xyloglucans promoted the elongation of etiolated pea (Pisum sativum L.) stem segments in a straight-growth bioassay designed for the determination of auxins. The oligosaccharides were most active at about 1 micromolar. We tested the relative growth-promoting activities of four HPLC-purified oligosaccharides which shared a common glucose{sub 4} {center dot} xylose{sub 3} (XG7) core. The substituted oligosaccharides XG8 (glucose{sub 4} {center dot} xylose{sub 3} {center dot} galactose) and XG9n (glucose{sub 4} {center dot} xylose{sub 3} {center dot} galactose{sub 2}) were more effective than XG7 itself and XG9 (glucose{sub 4} {center dot} xylose{submore » 3} {center dot} galactose {center dot} fucose). The same oligosaccharides also promoted the degradation, assayed viscometrically, of xyloglucan by an acidic cellulase from bean (Phaseolus vulgaris L.) leaves. The oligosaccharides were highly active at 10{sup {minus}4} molar, causing up to a fourfold increase in activity, but the effect was still detectable at 1 micromolar. Those oligosaccharides (XG8 and XG9n) which best promoted growth, stimulated cellulase activity to the greatest extent. The oligosaccharides did not stimulate the action of the cellulase in an assay based on the conversion of ({sup 3}H)xyloglucan to ethanol-soluble fragments. This suggests that the oligosaccharides enhanced the midchain hydrolysis of xyloglucan molecules (which would rapidly reduce the viscosity of the solution), at the expense of cleavage near the termini (which would yield ethanol-soluble products).« less

Special Form Testing of Sealed Source Encapsulation for High-Alpha-Activity Actinide Materials

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

Martinez, Oscar A

In the United States all transportation of radioactive material is regulated by the U.S. Department of Transportation (DOT). Beginning in 2008 a new type of sealed-source encapsulation package was developed and tested by Oak Ridge National Laboratory (ORNL). These packages contain high-alpha-activity actinides and are regulated and transported in accordance with the requirements for DOT Class 7 hazardous material. The DOT provides specific regulations pertaining to special form encapsulation designs. The special form designation indicates that the encapsulated radioactive contents have a very low probability of dispersion even when subjected to significant structural events. The special form designs have beenmore » shown to simplify the delivery, transport, acceptance, and receipt processes. It is intended for these sealed-source encapsulations to be shipped to various facilities making it very advantageous for them to be certified as special form. To this end, DOT Certificates of Competent Authority (CoCAs) have been sought for the design suitable for containing high-alpha-activity actinide materials. This design consists of the high-alpha-activity material encapsulated within a triangular zirconia canister, referred to as a ZipCan, tile that is then enclosed by a spherical shell. The spherical shell design, with ZipCan tile inside, was tested for compliance with the special form regulations found in 49 CFR 173.469. The spherical enclosure was subjected to 9-m impact, 1 m percussion, and 10-minute thermal tests at the Packaging Evaluation Facility located at the National Transportation Research Center in Knoxville, TN USA and operated by ORNL. Before and after each test, the test units were subjected to a helium leak check and a bubble test. The ZipCan tiles and core were also subjected to the tests required for ISO 2919:2012(E), including a Class IV impact test and heat test and subsequently subjected to helium leakage rate tests [49 CFR 173.469(a)(4)(i)]. The impact-tile test unit contained a nonradioactive surrogate; however, the thermal test unit contained a radioactive source. This paper describes the regulatory special form tests and presents detailed impact and leak test results that demonstrate that the sealed source encapsulation designs satisfy the regulatory tests.« less

Antibiotic Use in Small Community Hospitals.

PubMed

Stenehjem, Edward; Hersh, Adam L; Sheng, Xiaoming; Jones, Peter; Buckel, Whitney R; Lloyd, James F; Howe, Stephen; Evans, R Scott; Greene, Tom; Pavia, Andrew T

2016-11-15

 Antibiotic use and misuse is driving drug resistance. Much of US healthcare takes place in small community hospitals (SCHs); 70% of all US hospitals have <200 beds. Antibiotic use in SCHs is poorly described. We evaluated antibiotic use using data from the National Healthcare and Safety Network antimicrobial use option from the Centers for Disease Control and Prevention.  We used Intermountain Healthcare's monthly antibiotic use reports for 19 hospitals from 2011 to 2013. Hospital care units were categorized as intensive care, medical/surgical, pediatric, or miscellaneous. Antibiotics were categorized based on spectrum of coverage. Antibiotic use rates, expressed as days of therapy per 1000 patient-days (DOT/1000PD), were calculated for each SCH and compared with rates in large community hospitals (LCHs). Negative-binomial regression was used to relate antibiotic use to predictor variables.  Total antibiotic use rates varied widely across the 15 SCHs (median, 436 DOT/1000PD; range, 134-671 DOT/1000PD) and were similar to rates in 4 LCHs (509 DOT/1000PD; 406-597 DOT/1000PD). The proportion of patient-days spent in the respective unit types varied substantially within SCHs and had a large impact on facility-level rates. Broad-spectrum antibiotics accounted for 26% of use in SCHs (range, 8%-36%), similar to the proportion in LCHs (32%; range, 26%-37%). Case mix index, proportion of patient-days in specific unit types, and season were significant predictors of antibiotic use.  There is substantial variation in patterns of antibiotic use among SCHs. Overall usage in SCHs is similar to usage in LCHs. Small hospitals need to become a focus of stewardship efforts. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Effect of DOTS Treatment on Vitamin D Levels in Pulmonary Tuberculosis.

PubMed

Naik, Akshatha Lalesh; Rajan, Madan Gopal; Manjrekar, Poornima A; Shenoy, Mamatha T; Shreelata, Souparnika; Srikantiah, Rukmini Mysore; Hegde, Anupama

2017-04-01

Vitamin D (Vit D) modulates a variety of processes and regulatory systems including host defense, inflammation, immunity, and repair. Vit D Deficiency (VDD) is been implicated as a cause in diabetes, immune dysfunction and Tuberculosis (TB). Impaired metabolism of Vit D and an adverse outcome is associated with Pulmonary Tuberculosis (PTB). Directly Observed Treatment Short Course (DOTS) consist of drugs like rifampicin and isoniazid, which respectively cause accelerated loss of Vit D due to increased clearance and impairment of 25-hydroxylation causing diminished Vit D action. The aim of the present study was to estimate and compare serum Vit D status in newly diagnosed PTB patients before and after DOTS to validate the supplementation of Vit D in PTB patients. Forty four newly diagnosed PTB patients of both the sexes in the age group of 18 to 60 years before starting DOTS were recruited to participate in this non- randomized controlled trial with their voluntary consent. Vit D status in these patients and the effect of DOTS on Vit D were evaluated. Mean Vit D levels of the study population aged 43±13 years was 20.74 ng/ml (normal >30 ng/ml) at the time of diagnosis. After completion of six months of therapy mean Vit D reduced to 17.49 ng/ml (p-value=0.041). On individual observations, 70% of the participants showed a decrease in Vit D levels from their baseline, whereas 30% showed an increase. Comparison between the two groups indicated the possible role of younger age in the improved status. VDD was seen in PTB patients, which worsened in majority of the study population after treatment; hence it would be advisable to recommend Vit D supplementation in PTB patients for a better outcome.

49 CFR Appendix C to Part 180 - Eddy Current Examination With Visual Inspection for DOT 3AL Cylinders Manufactured of Aluminum...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Eddy Current Examination With Visual Inspection... PACKAGINGS Pt. 180, App. C Appendix C to Part 180—Eddy Current Examination With Visual Inspection for DOT 3AL... procedure applicable to the test equipment it uses to perform eddy current examinations. 2. Visual...

Hemostatic bioactivity of novel Pollen Typhae Carbonisata-derived carbon quantum dots.

PubMed

Yan, Xin; Zhao, Yan; Luo, Juan; Xiong, Wei; Liu, Xiaoman; Cheng, Jinjun; Wang, Yongzhi; Zhang, Meiling; Qu, Huihua

2017-09-05

Pollen Typhae Carbonisata (PTC) is a type of calcined herb drug that has been used as a hemostatic medicine to promote hemostasis for thousands of years. In this study, we discovered and separated novel water-soluble carbon quantum dots (CQDs, named PTC-CQDs) from aqueous extracts of PTC. These PTC-CDs were characterized using transmission electron microscopy (TEM) and high-resolution TEM, as well as Fourier transform infrared, ultraviolet-visible, and fluorescence spectroscopy. Then, we assessed the anti-hemorrhagic effects and related hemostatic mechanisms of the obtained PTC-CQDs. The PTC-CQDs separated from PTC are spherical, monodisperse, and have a narrow size distribution between 2 and 8 nm. In the pharmacology experiment, remarkable anti-hemorrhage effects of PTC-CQDs were revealed. Additionally, the rats showed a profound decrease in activated partial thromboplastin time and increase in fibrinogen and PLT after PTC-CQDs treatment. These results indicated the explicit hemostasis effect of PTC-CQDs, which not only provided a new idea for the material research of PTC, but have also provided new insights into potential biomedical and healthcare applications of CQDs in the field of haemorrhage control and laid a solid foundation for future drug discovery.

Synthesis and properties of unagglomerated nanocomposite particles for nanomedical applications

NASA Astrophysics Data System (ADS)

Rouse, Sarah M.

2005-11-01

Methods have been developed to prepare stable, unagglomerated active-medical-agent nanoparticles in a range of sizes, based on reverse-micelle microemulsion techniques. The process used to prepare monodisperse, spherical nanocomposite particles is based on methods originally outlined in detail by Adair et al. and Li et al. The "Molecular Dot" (MD) nanoparticles incorporate a variety of medically-active substances, such as organic fluorophores and therapeutic drugs, internally distributed in silica, titania, calcium phosphate, or calcium phospho-silicate matrices. The synthesis techniques have also been modified to produce nanoparticles containing combinations of fluorophores and medicinal agents, in order to monitor drug release and location. The specific biomedical application for the nanocomposite particles dictates the selection of core and shell-matrix materials. For example, the protective shell-matrices of the silica and titania MDs shield the active-medical agents from damage due to changes in pH, temperature, and other environmental effects. Conversely, the calcium phosphate and calcium phospho-silicate shell-matrix nanoparticles can potentially be engineered to dissolve in physiological environments. The method used to remove residual precursor materials while maintaining a well-dispersed assembly of nanoparticles is critical to the use of nanocolloids in medical applications. The dispersion approach is based on protection-dispersion theory tailored to accommodate the high surface areas and reactivity of sub-50 nm particles in aqueous or water/ethanol mixtures. Dispersion of the nanocomposite particles is further enhanced with the use of size-exclusion high performance liquid chromatography (HPLC) to simultaneously wash and disperse the nanocomposite particle suspensions. The state of dispersion of the nanosuspensions is evaluated using the average agglomeration number (AAN) approach in conjunction with other characterization techniques. The formulation of a non-aggregating colloid to deliver active-medical agents has the potential to revolutionize controlled, targeted, systemic delivery for a variety of drug and genetic therapies. The active-medical agent nanoparticles may be applied to a range of biomedical applications, including bioimaging, drug delivery, gene therapy, and combinations thereof. The fluorescent Molecular Dot nanoparticles have been utilized in applications such as in vitro cell labeling, as well as chemical and biological targeting. In addition, the Molecular Dots are a promising alternative to current bioimaging technologies, as the fluorescent emissions from the nanoparticulates do not exhibit blinking/intermittent qualities. (Abstract shortened by UMI.)

Ratiometric fluorescent nanosensor based on carbon dots for the detection of mercury ion

NASA Astrophysics Data System (ADS)

Ma, Yusha; Mei, Jing; Bai, Jianliang; Chen, Xu; Ren, Lili

2018-05-01

A novel ratiometric fluorescent nanosensor based on carbon dots has been synthesized via bonding rhodamine B hydrazide to the carbon dots surface by an amide reaction. The ratiometric fluorescent nanosensor showed only a single blue fluorescence emission around 450 nm. While, as mercury ion was added, due to the open-ring of rhodamine moiety bonded on the CDs surface, the orange emission of the open-ring rhodamine would increase obviously according to the concentration of mercury ion, resulting in the distinguishable dual emissions at 450 nm and 575 nm under a single 360 excitation wavelength. Meanwhile, the ratiometric fluorescent nanosensor based on carbon dots we prepared is more sensitive to qualitative and semi-quantitative detection of mercury ion in the range of 0–100 μM, because fluorescence changes gradually from blue to orange emission under 365 nm lamp with the increasing of mercury ion in the tested solution.

Impact of threading dislocation density on the lifetime of InAs quantum dot lasers on Si

NASA Astrophysics Data System (ADS)

Jung, Daehwan; Herrick, Robert; Norman, Justin; Turnlund, Katherine; Jan, Catherine; Feng, Kaiyin; Gossard, Arthur C.; Bowers, John E.

2018-04-01

We investigate the impact of threading dislocation density on the reliability of 1.3 μm InAs quantum dot lasers epitaxially grown on Si. A reduction in the threading dislocation density from 2.8 × 108 cm-2 to 7.3 × 106 cm-2 has improved the laser lifetime by about five orders of magnitude when aged continuous-wave near room temperature (35 °C). We have achieved extrapolated lifetimes (time to double initial threshold) more than 10 × 106 h. An accelerated laser aging test at an elevated temperature (60 °C) reveals that p-modulation doped quantum dot lasers on Si retain superior reliability over unintentionally doped ones. These results suggest that epitaxially grown quantum dot lasers could be a viable approach to realize a reliable, scalable, and efficient light source on Si.

A real-time spectrum acquisition system design based on quantum dots-quantum well detector

NASA Astrophysics Data System (ADS)

Zhang, S. H.; Guo, F. M.

2016-01-01

In this paper, we studied the structure characteristics of quantum dots-quantum well photodetector with response wavelength range from 400 nm to 1000 nm. It has the characteristics of high sensitivity, low dark current and the high conductance gain. According to the properties of the quantum dots-quantum well photodetectors, we designed a new type of capacitive transimpedence amplifier (CTIA) readout circuit structure with the advantages of adjustable gain, wide bandwidth and high driving ability. We have implemented the chip packaging between CTIA-CDS structure readout circuit and quantum dots detector and tested the readout response characteristics. According to the timing signals requirements of our readout circuit, we designed a real-time spectral data acquisition system based on FPGA and ARM. Parallel processing mode of programmable devices makes the system has high sensitivity and high transmission rate. In addition, we realized blind pixel compensation and smoothing filter algorithm processing to the real time spectrum data by using C++. Through the fluorescence spectrum measurement of carbon quantum dots and the signal acquisition system and computer software system to realize the collection of the spectrum signal processing and analysis, we verified the excellent characteristics of detector. It meets the design requirements of quantum dot spectrum acquisition system with the characteristics of short integration time, real-time and portability.

Sensitive fluorescence detection of mercury(ii) in aqueous solution by the fluorescence quenching effect of MoS2 with DNA functionalized carbon dots.

PubMed

Srinivasan, K; Subramanian, K; Murugan, K; Dinakaran, K

2016-10-24

A rapid and sensitive fluorescent sensor based on the MoS 2 nanosheet/DNA/carbon dot nanoassembly has been developed towards the detection of mercury(ii) present in environmental samples. Bio-carbon dots (CDs) having strong fluorescence maxima at 451 nm were synthesized via one-step treatment with honey under low temperature carbonization. These CDs were nearly spherical with good size distribution and excellent monodispersity, and the average sizes of CD were around 2-4 nm as evidenced from transmission electron microscopy. The conjugation of DNA strands on the surface of the carbon dots provided an efficient fluorescent probe. The fluorescence of the MoS 2 nanosheet/DNA/carbon dot nanoassembly enhanced gradually with the increase in the concentration of Hg 2+ ions and the detection limit was found to be 1.02 nM. Furthermore, the fluorescence intensity was found to be linear with the concentration of Hg 2+ ions in the range from 0 to 10 nM and their respective coefficient of determination was found to be 0.93676 and 0.98178. The present MoS 2 nanosheet/DNA/carbon dot nanoassembly is highly selective toward Hg 2+ ions over a wide range of metal ions tested.

An Evaluation of Time-Trial-Based Predictions of V[Combining Dot Above]O2max and Recommended Training Paces for Collegiate and Recreational Runners.

PubMed

Scudamore, Eric M; Barry, Vaughn W; Coons, John M

2018-04-01

Scudamore, EM, Barry, VW, and Coons, JM. An Evaluation of time-trial-based predictions of V[Combining Dot Above]O2max and recommended training paces for collegiate and recreational runners. J Strength Cond Res 32(4): 1137-1143, 2018-The purpose of the current study was to determine the accuracy of Jack Daniels' VDOT Running Calculator for the prediction of V[Combining Dot Above]O2max, and recommendations of interval and training paces (pIN and pTH) in samples of National Collegiate Athletic Association Division 1 track athletes (ATH, n = 11) and recreational runners (REC; n = 9). Predicted variable data were obtained using results from indoor 5-km time-trials. Data from the VDOT Calculator were compared with laboratory-tested V[Combining Dot Above]O2max, pace at V[Combining Dot Above]O2max (V[Combining Dot Above]O2maxpace), and lactate threshold pace (LTpace). Results indicated that VDOT underestimated V[Combining Dot Above]O2max in ATH (t(10) = -6.00, p < 0.001, d = 1.75) and REC (t(8) = -8.96, p < 0.001, d = 3.44). Follow-up between-groups analysis indicated that the difference between VDOT and V[Combining Dot Above]O2max was significantly greater in REC than in ATH (p = 0.0031, d = 1.59). pIN was slower than V[Combining Dot Above]O2maxpace in REC (t(8) = -4.26, p = 0.003, d = 1.76), but not different in ATH (t(10) = 0.52, p = 0.614, d = 0.14). Conversely, pTH was faster than LTpace in ATH (t(8) = -4.17, p = 0.003, d = 1.49), but not different in REC (t(8) = 1.64, p = 0.139, d = 0.57). Practically, pTH can be confidently used for threshold training regardless of the ability level. pIN also seemed to be accurate for ATH, but may be not be optimal for improving V[Combining Dot Above]O2max in REC. Practitioners should interpret VDOT with caution as it may underestimate V[Combining Dot Above]O2max.

Sub-optimal delivery of intermittent preventive treatment for malaria in pregnancy in Nigeria: influence of provider factors.

PubMed

Onoka, Chima A; Onwujekwe, Obinna E; Hanson, Kara; Uzochukwu, Benjamin S

2012-09-07

The level of access to intermittent preventive treatment for malaria in pregnancy (IPTp) in Nigeria is still low despite relatively high antenatal care coverage in the study area. This paper presents information on provider factors that affect the delivery of IPTp in Nigeria. Data were collected from heads of maternal health units of 28 public and six private health facilities offering antenatal care (ANC) services in two districts in Enugu State, south-east Nigeria. Provider knowledge of guidelines for IPTp was assessed with regard to four components: the drug used for IPTp, time of first dose administration, of second dose administration, and the strategy for sulphadoxine-pyrimethamine (SP) administration (directly observed treatment, DOT). Provider practices regarding IPTp and facility-related factors that may explain observations such as availability of SP and water were also examined. Only five (14.7%) of all 34 providers had correct knowledge of all four recommendations for provision of IPTp. None of them was a private provider. DOT strategy was practiced in only one and six private and public providers respectively. Overall, 22 providers supplied women with SP in the facility and women were allowed to take it at home. The most common reason for doing so amongst public providers was that women were required to come for antenatal care on empty stomachs to enhance the validity of manual fundal height estimation. Two private providers did not think it was necessary to use the DOT strategy because they assumed that women would take their drugs at home. Availability of SP and water in the facility, and concerns about side effects were not considered impediments to delivery of IPTp. There was low level of knowledge of the guidelines for implementation of IPTp by all providers, especially those in the private sector. This had negative effects such as non-practice of DOT strategy by most of the providers, which can lead to low levels of adherence to IPTp and ineffectiveness of IPTp. Capacity development and regular supportive supervisory visits by programme managers could help improve the provision of IPTp.

Graphene quantum dots for the inhibition of β amyloid aggregation

NASA Astrophysics Data System (ADS)

Liu, Yibiao; Xu, Li-Ping; Dai, Wenhao; Dong, Haifeng; Wen, Yongqiang; Zhang, Xueji

2015-11-01

The aggregation of Aβ peptides is a crucial factor leading to Alzheimer's disease (AD). Inhibiting the Aβ peptide aggregation has become one of the most essential strategies to treat AD. In this work, efficient and low-cytotoxicity inhibitors, graphene quantum dots (GQDs) are reported for their application in inhibiting the aggregation of Aβ peptides. Compared to other carbon materials, the low cytotoxicity and great biocompatibility of GQDs give an advantage to the clinical research for AD. In addition, the GQDs may cross the blood-brain barrier (BBB) because of the small size. It is believed that GQDs may be therapeutic agents against AD. This work provides a novel insight into the development of Alzheimer's drugs.The aggregation of Aβ peptides is a crucial factor leading to Alzheimer's disease (AD). Inhibiting the Aβ peptide aggregation has become one of the most essential strategies to treat AD. In this work, efficient and low-cytotoxicity inhibitors, graphene quantum dots (GQDs) are reported for their application in inhibiting the aggregation of Aβ peptides. Compared to other carbon materials, the low cytotoxicity and great biocompatibility of GQDs give an advantage to the clinical research for AD. In addition, the GQDs may cross the blood-brain barrier (BBB) because of the small size. It is believed that GQDs may be therapeutic agents against AD. This work provides a novel insight into the development of Alzheimer's drugs. Electronic supplementary information (ESI) available: Dose-dependent inhibition of Aβ1-42 fibrillization by GQDs; the photoluminescence spectra of all five GQDs with different charges in water/ethanol; TEM images of other four GQDs with different charges. See DOI: 10.1039/c5nr06282a

Disruptor of telomeric silencing 1-like (DOT1L): disclosing a new class of non-nucleoside inhibitors by means of ligand-based and structure-based approaches.

PubMed

Sabatino, Manuela; Rotili, Dante; Patsilinakos, Alexandros; Forgione, Mariantonietta; Tomaselli, Daniela; Alby, Fréderic; Arimondo, Paola B; Mai, Antonello; Ragno, Rino

2018-03-01

Chemical inhibition of chromatin-mediated signaling involved proteins is an established strategy to drive expression networks and alter disease progression. Protein methyltransferases are among the most studied proteins in epigenetics and, in particular, disruptor of telomeric silencing 1-like (DOT1L) lysine methyltransferase plays a key role in MLL-rearranged acute leukemia Selective inhibition of DOT1L is an established attractive strategy to breakdown aberrant H3K79 methylation and thus overexpression of leukemia genes, and leukemogenesis. Although numerous DOT1L inhibitors have been several structural data published no pronounced computational efforts have been yet reported. In these studies a first tentative of multi-stage and LB/SB combined approach is reported in order to maximize the use of available data. Using co-crystallized ligand/DOT1L complexes, predictive 3-D QSAR and COMBINE models were built through a python implementation of previously reported methodologies. The models, validated by either modeled or experimental external test sets, proved to have good predictive abilities. The application of these models to an internal library led to the selection of two unreported compounds that were found able to inhibit DOT1L at micromolar level. To the best of our knowledge this is the first report of quantitative LB and SB DOT1L inhibitors models and their application to disclose new potential epigenetic modulators.

Disruptor of telomeric silencing 1-like (DOT1L): disclosing a new class of non-nucleoside inhibitors by means of ligand-based and structure-based approaches

NASA Astrophysics Data System (ADS)

Sabatino, Manuela; Rotili, Dante; Patsilinakos, Alexandros; Forgione, Mariantonietta; Tomaselli, Daniela; Alby, Fréderic; Arimondo, Paola B.; Mai, Antonello; Ragno, Rino

2018-03-01

Chemical inhibition of chromatin-mediated signaling involved proteins is an established strategy to drive expression networks and alter disease progression. Protein methyltransferases are among the most studied proteins in epigenetics and, in particular, disruptor of telomeric silencing 1-like (DOT1L) lysine methyltransferase plays a key role in MLL-rearranged acute leukemia Selective inhibition of DOT1L is an established attractive strategy to breakdown aberrant H3K79 methylation and thus overexpression of leukemia genes, and leukemogenesis. Although numerous DOT1L inhibitors have been several structural data published no pronounced computational efforts have been yet reported. In these studies a first tentative of multi-stage and LB/SB combined approach is reported in order to maximize the use of available data. Using co-crystallized ligand/DOT1L complexes, predictive 3-D QSAR and COMBINE models were built through a python implementation of previously reported methodologies. The models, validated by either modeled or experimental external test sets, proved to have good predictive abilities. The application of these models to an internal library led to the selection of two unreported compounds that were found able to inhibit DOT1L at micromolar level. To the best of our knowledge this is the first report of quantitative LB and SB DOT1L inhibitors models and their application to disclose new potential epigenetic modulators.

Eco-friendly intracellular biosynthesis of CdS quantum dots without changing Escherichia coli's antibiotic resistance.

PubMed

Yan, Zheng-Yu; Du, Qing-Qing; Qian, Jing; Wan, Dong-Yu; Wu, Sheng-Mei

2017-01-01

In the paper, a green and efficient biosynthetical technique was reported for preparing cadmium sulfide (CdS) quantum dots, in which Escherichia coli (E. coli) was chosen as a biomatrix. Fluorescence emission spectra and fluorescent microscopic photographs revealed that as-produced CdS quantum dots had an optimum fluorescence emission peak located at 470nm and emitted a blue-green fluorescence under ultraviolet excitation. After extracted from bacterial cells and located the nanocrystals' foci in vivo, the CdS quantum dots showed a uniform size distribution by transmission electron microscope. Through the systematical investigation of the biosynthetic conditions, including culture medium replacement, input time point of cadmium source, working concentrations of raw inorganic ions, and co-cultured time spans of bacteria and metal ions in the bio-manufacture, the results revealed that CdS quantum dots with the strongest fluorescence emission were successfully prepared when E. coli cells were in stationary phase, with the replacement of culture medium and following the incubation with 1.0×10 -3 mol/L cadmium source for 2 days. Results of antimicrobial susceptibility testing indicated that the sensitivities to eight types of antibiotics of E. coli were barely changed before and after CdS quantum dots were prepared in the mild temperature environment, though a slight fall of antibiotic resistance could be observed, suggesting hinted the proposed technique of producing quantum dots is a promising environmentally low-risk protocol. Copyright © 2016 Elsevier Inc. All rights reserved.

Resistance factors for 100% dynamic testing, with and without static load tests.

DOT National Transportation Integrated Search

2011-05-01

Current department of transportation (DOT) and Federal Highway Administration (FHWA) practice has highly : variable load and resistance factor design (LRFD) resistance factors, , for driven piles from design (e.g., Standard : Penetration Tests (SPT...

Locomotive to Automobile Baseline Crash Tests

DOT National Transportation Integrated Search

1975-08-01

Four Locomotive to Automobile Crash tests were performed by the Dynamic Science Division of Ultrasystems at DOT's High Speed Ground Test Center under contract to the Transportation Systems Center, which is conducting the work for the Federal Railroad...

TB control programmes: the challenges for Africa.

PubMed

Harries, T

1996-11-01

Governmental neglect of tuberculosis (TB), inadequately managed and inaccurately designed TB control programs, population growth, and the HIV epidemic account for the resurgence of TB in sub-Saharan Africa. The World Health Organization and the International Union against TB and Lung Disease have developed a TB control strategy that aims to reduce mortality, morbidity, and transmission of TB. It aims for an 85% cure rate among detected new cases of smear-positive TB and a 70% rate of detecting existing smear-positive TB cases. The strategy involves the provision of short-course chemotherapy (SCC) to all identified smear-positive TB cases through directly observed treatment (DOTS). SCC treatment regimens for smear-positive pulmonary TB recommended for sub-Saharan African countries are: initial phase = daily administration over 2 months of streptomycin, rifampicin, isoniazid, and pyrazinamide; continuation phase = 3 doses over 4 months of isoniazid and rifampicin or daily administration of thiacetazone and isoniazid or of ethambutol and isoniazid. A TB control policy must be implemented to bring about effective TB control. The essential elements of this policy include political commitment, case detection through passive case-finding, SCC, a regular supply of essential drugs, and a monitoring and evaluation system. Political commitment involves establishing a National TB Control Program to be integrated into the existing health structure. Increased awareness of TB in the community and among health workers and a reference laboratory are needed to make case finding successful. A distribution and logistics system is needed to ensure uninterrupted intake of drugs throughout treatment. These regimens have been very successful and cost-effective but pose several disadvantages (e.g., heavy workload of recommended 3 sputum smear tests). A simplified approach involves 1 initial sputum smear for 6 months; 6-months, intermittent rifampicin-based therapy, 100% DOTS throughout entire treatment course, and ascertainment of treatment completion rates and mortality rates in all patients.

One-pot hydrothermal synthesis of ZnS quantum dots/graphene hybrids as a dual anode for sodium ion and lithium ion batteries

NASA Astrophysics Data System (ADS)

Zhang, Rupeng; Wang, Yu; Jia, Mengqiu; Xu, Junjie; Pan, Erzhuang

2018-04-01

Committed to research high-performance sodium-ion batteries(SIBs) and lithium-ion batteries(LIBs) anode materials is attractive but challenging. Among the many promising anode materials, sulfides are considered as promising available anode material. In this paper, we successfully synthesized uniformly dispersed ZnS quantum dots (QDs) with sub-10-nm-scale on graphene nanosheets via a facile hydrothermal method. The prepared ZnS/graphene composites was studied as a dual anode for sodium-ion and lithium-ion batteries. Tested against SIBs, the nanocomposites exhibits an impressive specific capacity of 491 mAh/g at 100 mA/g after 100 cycles. Tested against LIBs, the nanocomposites delivers a superior specific capacity of 759 mAh/g at 100 mA/g after 100 cycles. This excellent performance is mainly due to the fact that graphene can improve the conductivity of the composites and effectively prevent the agglomeration and pulverization of ZnS quantum dots during cycling. Meanwhile, ZnS quantum dots with sub-10-nm-scale may also shorten diffuse path and reduce migration barrier, which is in favor of the full utilization of the active material and the improvement of the stability of the structure

Performance testing of LiDAR exploitation software

NASA Astrophysics Data System (ADS)

Varela-González, M.; González-Jorge, H.; Riveiro, B.; Arias, P.

2013-04-01

Mobile LiDAR systems are being used widely in recent years for many applications in the field of geoscience. One of most important limitations of this technology is the large computational requirements involved in data processing. Several software solutions for data processing are available in the market, but users are often unknown about the methodologies to verify their performance accurately. In this work a methodology for LiDAR software performance testing is presented and six different suites are studied: QT Modeler, AutoCAD Civil 3D, Mars 7, Fledermaus, Carlson and TopoDOT (all of them in x64). Results depict as QTModeler, TopoDOT and AutoCAD Civil 3D allow the loading of large datasets, while Fledermaus, Mars7 and Carlson do not achieve these powerful performance. AutoCAD Civil 3D needs large loading time in comparison with the most powerful softwares such as QTModeler and TopoDOT. Carlson suite depicts the poorest results among all the softwares under study, where point clouds larger than 5 million points cannot be loaded and loading time is very large in comparison with the other suites even for the smaller datasets. AutoCAD Civil 3D, Carlson and TopoDOT show more threads than other softwares like QTModeler, Mars7 and Fledermaus.

Ratio abstraction over discrete magnitudes by newly hatched domestic chicks (Gallus gallus).

PubMed

Rugani, Rosa; McCrink, Koleen; de Hevia, Maria-Dolores; Vallortigara, Giorgio; Regolin, Lucia

2016-07-28

A large body of literature shows that non-human animals master a variety of numerical tasks, but studies involving proportional discrimination are sparse and primarily done with mature animals. Here we trained 4-day-old domestic chicks (Gallus gallus) to respond to stimuli depicting multiple examples of the proportion 4:1 when compared with the proportion 2:1. Stimuli were composed of green and red dot arrays; for the rewarded 4:1 proportion, 4 green dots for every red dot (e.g. ratios: 32:8, 12:3, and 44:11). The birds continued to discriminate when presented with new ratios at test (such as 20:5), characterized by new numbers of dots and new spatial configurations (Experiment 1). This indicates that chicks can extract the common proportional value shared by different ratios and apply it to new ones. In Experiment 2, chicks identified a specific proportion (2:1) from either a smaller (4:1) or a larger one (1:1), demonstrating an ability to represent the specific, and not relative, value of a particular proportion. Again, at test, chicks selectively responded to the previously reinforced proportion from new ratios. These findings provide strong evidence for very young animals' ability to extract, identify, and productively use proportion information across a range of different amounts.

Semiconductor quantum dots as Förster resonance energy transfer donors for intracellularly-based biosensors

NASA Astrophysics Data System (ADS)

Field, Lauren D.; Walper, Scott A.; Susumu, Kimihiro; Oh, Eunkeu; Medintz, Igor L.; Delehanty, James B.

2017-02-01

Förster resonance energy transfer (FRET)-based assemblies currently comprise a significant portion of intracellularly based sensors. Although extremely useful, the fluorescent protein pairs typically utilized in such sensors are still plagued by many photophysical issues including significant direct acceptor excitation, small changes in FRET efficiency, and limited photostability. Luminescent semiconductor nanocrystals or quantum dots (QDs) are characterized by many unique optical properties including size-tunable photoluminescence, broad excitation profiles coupled to narrow emission profiles, and resistance to photobleaching, which can cumulatively overcome many of the issues associated with use of fluorescent protein FRET donors. Utilizing QDs for intracellular FRET-based sensing still requires significant development in many areas including materials optimization, bioconjugation, cellular delivery and assay design and implementation. We are currently developing several QD-based FRET sensors for various intracellular applications. These include sensors targeting intracellular proteolytic activity along with those based on theranostic nanodevices for monitoring drug release. The protease sensor is based on a unique design where an intracellularly expressed fluorescent acceptor protein substrate assembles onto a QD donor following microinjection, forming an active complex that can be monitored in live cells over time. In the theranostic configuration, the QD is conjugated to a carrier protein-drug analogue complex to visualize real-time intracellular release of the drug from its carrier in response to an external stimulus. The focus of this talk will be on the design, properties, photophysical characterization and cellular application of these sensor constructs.

49 CFR 234.273 - Results of inspections and tests.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Results of inspections and tests. 234.273 Section....273 Results of inspections and tests. (a) Results of inspections and tests made in compliance with.../DOT inventory number, place and date, equipment tested, results of tests, repairs, replacements...

49 CFR 234.273 - Results of inspections and tests.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Results of inspections and tests. 234.273 Section....273 Results of inspections and tests. (a) Results of inspections and tests made in compliance with.../DOT inventory number, place and date, equipment tested, results of tests, repairs, replacements...

49 CFR 234.273 - Results of inspections and tests.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Results of inspections and tests. 234.273 Section....273 Results of inspections and tests. (a) Results of inspections and tests made in compliance with.../DOT inventory number, place and date, equipment tested, results of tests, repairs, replacements...

Mathematical difficulties in nonverbal learning disability or co-morbid dyscalculia and dyslexia.

PubMed

Mammarella, Irene C; Bomba, Monica; Caviola, Sara; Broggi, Fiorenza; Neri, Francesca; Lucangeli, Daniela; Nacinovich, Renata

2013-01-01

The main goal of the present study was to shed further light on the weaknesses of children with different profiles of mathematical difficulties, testing children with nonverbal learning disability (NLD), co-morbid dyscalculia and dyslexia (D&D), or typical development (TD). Sixteen children with NLD, 15 with D&D, and 16 with TD completed tasks derived from Butterworth (2003 ) and divided into: a capacity subscale (i.e., a number-dots comparison task, a number comparison task, and a dots comparison task); and an achievement subscale (i.e., mental calculations and arithmetical fact retrieval). Children with NLD were impaired in the dots comparison task, children with D&D in the mental calculation and arithmetical facts.

Comparison of DOT-ELISA and Standard-ELISA for Detection of the Vibrio cholerae Toxin in Culture Supernatants of Bacteria Isolated from Human and Environmental Samples.

PubMed

Meza-Lucas, Antonio; Pérez-Villagómez, María-Fernanda; Martínez-López, José-Patricio; García-Rodea, Ricardo; Martínez-Castelán, María-Guadalupe; Escobar-Gutiérrez, Alejandro; de-la-Rosa-Arana, Jorge-Luis; Villanueva-Zamudio, Altagracia

2016-09-01

A comparison of DOT-ELISA and Standard-ELISA was made for detection of Vibrio cholerae toxin in culture supernatants of bacteria isolated from human and environmental samples. A total of 293 supernatants were tested in a double blind assay. A correlation of 100 % was obtained between both techniques. The cholera toxin was found in 20 Inaba and 3 Ogawa strains. Positive samples were from seafood (17 samples), potable water (1 sample) and sewage (5 samples). The DOT-ELISA was useful as the standard-ELISA to confirm the presence of cholera toxin in the environmental samples.

Validity and feasibility of the EMG direct observation tool (EMG-DOT).

PubMed

Leep Hunderfund, Andrea N; Rubin, Devon I; Laughlin, Ruple S; Sorenson, Eric J; Watson, James C; Jones, Lyell K; Juul, Dorthea; Park, Yoon Soo

2016-04-26

To develop a new workplace-based EMG direct observation tool (EMG-DOT) and gather validity evidence supporting its use for assessing electrodiagnostic skills among postgraduate medical trainees. The EMG-DOT was developed by experts using an iterative process. Validity evidence from content, response process, internal structure, relations to other variables, and consequences of testing was collected during the 2013-2014 academic year. Of 3,412 studies performed by trainees during the study period, 299 (9%) were assessed using the EMG-DOT. Of these, 203 (68%) involved a physician rater and 96 (32%) involved a technician rater. The 14-item EMG-DOT had excellent internal-consistency reliability (Cronbach α 0.94). Correlations between individual items and criterion-referenced global ratings of performance ranged from 0.36 to 0.72 (all p < 0.001). Mean total scores increased from 70% to 80% over 4 months of the EMG rotation (p < 0.001) despite a corresponding significant increase in case complexity (0.21-0.74 on a 3-point rating scale; p < 0.001). Trainees reported that the observational assessment exercise improved their knowledge or skills in 82% of encounters (188/230) and that feedback generated by the EMG-DOT improved the quality of care provided to patients in 58% (133/230). Trainees were "satisfied" or "very satisfied" with the observational assessment exercise in 96% of encounters (234/243). This study provides validity evidence supporting the use of EMG-DOT scores to assess electrodiagnostic skills of residents and fellows. The EMG-DOT can be used to inform milestone-based assessments of trainee performance in neurology, child neurology, physical medicine and rehabilitation, neuromuscular, and clinical neurophysiology training programs. © 2016 American Academy of Neurology.

An optically stimulated luminescence dosimeter for measuring patient exposure from imaging guidance procedures.

PubMed

Ding, George X; Malcolm, Arnold W

2013-09-07

There is a growing interest in patient exposure resulting from an x-ray imaging procedure used in image-guided radiation therapy. This study explores a feasibility to use a commercially available optically stimulated luminescence (OSL) dosimeter, nanoDot, for estimating imaging radiation exposure to patients. The kilovoltage x-ray sources used for kV-cone-beam CT (CBCT) imaging acquisition procedures were from a Varian on-board imager (OBI) image system. An ionization chamber was used to determine the energy response of nanoDot dosimeters. The chamber calibration factors for x-ray beam quality specified by half-value layer were obtained from an Accredited Dosimetry Calibration Laboratory. The Monte Carlo calculated dose distributions were used to validate the dose distributions measured by using the nanoDot dosimeters in phantom and in vivo. The range of the energy correction factors for the nanoDot as a function of photon energy and bow-tie filters was found to be 0.88-1.13 for different kVp and bow-tie filters. Measurement uncertainties of nanoDot were approximately 2-4% after applying the energy correction factors. The tests of nanoDot placed on a RANDO phantom and on patient's skin showed consistent results. The nanoDot is suitable dosimeter for in vivo dosimetry due to its small size and manageable energy dependence. The dosimeter placed on a patient's skin has potential to serve as an experimental method to monitor and to estimate patient exposure resulting from a kilovoltage x-ray imaging procedure. Due to its large variation in energy response, nanoDot is not suitable to measure radiation doses resulting from mixed beams of megavoltage therapeutic and kilovoltage imaging radiations.

An optically stimulated luminescence dosimeter for measuring patient exposure from imaging guidance procedures

NASA Astrophysics Data System (ADS)

Ding, George X.; Malcolm, Arnold W.

2013-09-01

There is a growing interest in patient exposure resulting from an x-ray imaging procedure used in image-guided radiation therapy. This study explores a feasibility to use a commercially available optically stimulated luminescence (OSL) dosimeter, nanoDot, for estimating imaging radiation exposure to patients. The kilovoltage x-ray sources used for kV-cone-beam CT (CBCT) imaging acquisition procedures were from a Varian on-board imager (OBI) image system. An ionization chamber was used to determine the energy response of nanoDot dosimeters. The chamber calibration factors for x-ray beam quality specified by half-value layer were obtained from an Accredited Dosimetry Calibration Laboratory. The Monte Carlo calculated dose distributions were used to validate the dose distributions measured by using the nanoDot dosimeters in phantom and in vivo. The range of the energy correction factors for the nanoDot as a function of photon energy and bow-tie filters was found to be 0.88-1.13 for different kVp and bow-tie filters. Measurement uncertainties of nanoDot were approximately 2-4% after applying the energy correction factors. The tests of nanoDot placed on a RANDO phantom and on patient's skin showed consistent results. The nanoDot is suitable dosimeter for in vivo dosimetry due to its small size and manageable energy dependence. The dosimeter placed on a patient's skin has potential to serve as an experimental method to monitor and to estimate patient exposure resulting from a kilovoltage x-ray imaging procedure. Due to its large variation in energy response, nanoDot is not suitable to measure radiation doses resulting from mixed beams of megavoltage therapeutic and kilovoltage imaging radiations.

Determinants of health system delay at public and private directly observed treatment, short course facilities in Lagos State, Nigeria: A cross-sectional study.

PubMed

Adejumo, Olusola Adedeji; Daniel, Olusoji James; Otesanya, Andrew Folarin; Adejumo, Esther Ngozi

2016-09-01

Despite several studies on health system delay (HSD) among tuberculosis (TB) patients in Nigeria, no study has compared HSD in private and public health facilities. This study assessed the determinants of HSD in public and private health facilities offering the directly observed treatment, short course (DOTS). A descriptive cross-sectional study was conducted. A total of 470 new smear-positive TB patients aged 14years and older were consecutively recruited between October 1, 2012, and December 31, 2012, from 34 (23 public and 11 private) DOTS facilities that offered treatment and microscopy services. Mann-Whitney U test and logistic regression were used to assess the determinants of HSD. The median HSD was longer at public DOTS facilities (14days; interquartile range [IQR] 10-21days) than private DOTS facilities (12.5days; IQR 10.0-14.0days, p=.002). Age and human immunodeficiency virus status were determinants of HSD at the public DOTS facilities, whereas sex and income were determinants of HSD at the private DOTS facilities. TB patients who first visited a nonhospital facility were over four times more likely (odds ratio 4.12; 95% confidence interval 2.25-7.54) to have prolonged HSD than those who first visited the government hospital when they first developed the symptoms of TB after controlling for other factors in the model. Determinants of HSD at the public and private DOTS facilities vary. Strategies to reduce HSD at both public and private DOTS facilities in Lagos State, Nigeria, are urgently needed. Copyright © 2016 Asian-African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

A novel drug delivery of 5-fluorouracil device based on TiO2/ZnS nanotubes.

PubMed

Faria, Henrique Antonio Mendonça; de Queiroz, Alvaro Antonio Alencar

2015-11-01

The structural and electronic properties of titanium oxide nanotubes (TiO2) have attracted considerable attention for the development of therapeutic devices and imaging probes for nanomedicine. However, the fluorescence response of TiO2 has typically been within ultraviolet spectrum. In this study, the surface modification of TiO2 nanotubes with ZnS quantum dots was found to produce a red shift in the ultra violet emission band. The TiO2 nanotubes used in this work were obtained by sol-gel template synthesis. The ZnS quantum dots were deposited onto TiO2 nanotube surface by a micelle-template inducing reaction. The structure and morphology of the resulting hybrid TiO2/ZnS nanotubes were investigated by scanning electron microscopy, transmission electron microscopy and X-ray diffraction techniques. According to the results of fluorescence spectroscopy, pure TiO2 nanotubes exhibited a high emission at 380nm (3.26eV), whereas TiO2/ZnS exhibited an emission at 410nm (3.02eV). The TiO2/ZnS nanotubes demonstrated good bio-imaging ability on sycamore cultured plant cells. The biocompatibility against mammalian cells (Chinese Hamster Ovarian Cells-CHO) suggesting that TiO2/ZnS may also have suitable optical properties for use as biological markers in diagnostic medicine. The drug release characteristic of TiO2/ZnS nanotubes was explored using 5-fluorouracil (5-FU), an anticancer drug used in photodynamic therapy. The results show that the TiO2/ZnS nanotubes are a promising candidate for anticancer drug delivery systems. Copyright © 2015 Elsevier B.V. All rights reserved.

A comparative study of the typhidot (Dot-EIA) and Widal tests in blood culture positive cases of typhoid fever.

PubMed

Khoharo, Haji Khan

2011-07-01

Seventy-six blood culture positive typhoid cases and forty-eight controls were studied. The typhidot test was positive in 74 (97.36%) cases, with a sensitivity, specificity and positive predictive value of 96%, 89.5%, and 95%, respectively, compared to the Widal test which was positive in 56 (73.68%) cases with a sensitivity, specificity, and positive predictive value of 72%, 87%, and 87%, respectively (P = 0.001). In the control group, seven (14.5%) cases tested positive for the Widal test and two (4.16%) for the typhidot (P = 0.001), yielding the sensitivity and specificity for the Widal test and the typhidot test of 63% and 83%, and 85% and 97%, respectively. We conclude that the Dot-EIA (enzyme immunoassay; typhidot) is a more sensitive and specific test which is easy to perform and more reliable compared to the Widal test and that it is useful in early therapy.

C8-structured carbon quantum dots: Synthesis, blue and green double luminescence, and origins of surface defects

NASA Astrophysics Data System (ADS)

Xifang, Chen; Wenxia, Zhang; Qianjin, Wang; Jiyang, Fan

Carbon quantum dots (CQDs) have attracted great attention in the past few years due to their low cytotoxicity, exploited various synthesis methods, unexampled abundance of raw materials on earth, and robust near-infrared to near-UV luminescence. Carbon nanoparticles have applications in biological labeling, delivery of drugs and biological molecules into cells, and light emitting diodes and lasing. CQDs generally exist as nanodiamonds or graphite quantum dots according to previous research reports. In this study, we report the first synthesis of the third-allotrope CQDs through carbonization of sucrose and study their luminescence properties. These CQDs have a body-centered cubic structure and each lattice point is composed of eight atoms which form a sub-cube (so called C8 crystal structure). High-resolution transmission electron microscopy and X-ray diffraction confirm the C8 structure of the synthesized carbon nanocrystallites with an average size of 2 nm. The C8 CQDs exhibit double-band luminescence with two peaks centered at around 432 and 520 nm. The study based on the photoluminescence, UV-Vis absorption, Fourier-transform infrared, and X-ray photoelectron spectroscopies reveals that the green emission originates from the C=O related surface defect.

Ultrasensitive NIR-SERRS Probes with Multiplexed Ratiometric Quantification for In Vivo Antibody Leads Validation.

PubMed

Kang, Homan; Jeong, Sinyoung; Jo, Ahla; Chang, Hyejin; Yang, Jin-Kyoung; Jeong, Cheolhwan; Kyeong, San; Lee, Youn Woo; Samanta, Animesh; Maiti, Kaustabh Kumar; Cha, Myeong Geun; Kim, Taek-Keun; Lee, Sukmook; Jun, Bong-Hyun; Chang, Young-Tae; Chung, Junho; Lee, Ho-Young; Jeong, Dae Hong; Lee, Yoon-Sik

2018-02-01

Immunotargeting ability of antibodies may show significant difference between in vitro and in vivo. To select antibody leads with high affinity and specificity, it is necessary to perform in vivo validation of antibody candidates following in vitro antibody screening. Herein, a robust in vivo validation of anti-tetraspanin-8 antibody candidates against human colon cancer using ratiometric quantification method is reported. The validation is performed on a single mouse and analyzed by multiplexed surface-enhanced Raman scattering using ultrasensitive and near infrared (NIR)-active surface-enhanced resonance Raman scattering nanoprobes (NIR-SERRS dots). The NIR-SERRS dots are composed of NIR-active labels and Au/Ag hollow-shell assembled silica nanospheres. A 93% of NIR-SERRS dots is detectable at a single-particle level and signal intensity is 100-fold stronger than that from nonresonant molecule-labeled spherical Au NPs (80 nm). The result of SERRS-based antibody validation is comparable to that of the conventional method using single-photon-emission computed tomography. The NIR-SERRS-based strategy is an alternate validation method which provides cost-effective and accurate multiplexing measurements for antibody-based drug development. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Magnetic bead-quantum dot assay for detection of a biomarker for traumatic brain injury

NASA Astrophysics Data System (ADS)

Kim, Chloe; Searson, Peter C.

2015-10-01

Current diagnostic methods for traumatic brain injury (TBI), which accounts for 15% of all emergency room visits, are limited to neuroimaging modalities. The challenges of accurate diagnosis and monitoring of TBI have created the need for a simple and sensitive blood test to detect brain-specific biomarkers. Here we report on an assay for detection of S100B, a putative biomarker for TBI, using antibody-conjugated magnetic beads for capture of the protein, and antibody-conjugated quantum dots for optical detection. From Western Blot, we show efficient antigen capture and concentration by the magnetic beads. Using magnetic bead capture and quantum dot detection in serum samples, we show a wide detection range and detection limit below the clinical cut-off level.Current diagnostic methods for traumatic brain injury (TBI), which accounts for 15% of all emergency room visits, are limited to neuroimaging modalities. The challenges of accurate diagnosis and monitoring of TBI have created the need for a simple and sensitive blood test to detect brain-specific biomarkers. Here we report on an assay for detection of S100B, a putative biomarker for TBI, using antibody-conjugated magnetic beads for capture of the protein, and antibody-conjugated quantum dots for optical detection. From Western Blot, we show efficient antigen capture and concentration by the magnetic beads. Using magnetic bead capture and quantum dot detection in serum samples, we show a wide detection range and detection limit below the clinical cut-off level. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr05608j

Receiver Test Selection Criteria

DOT National Transportation Integrated Search

2015-03-12

The DOT requests that GPS manufacturers submit receivers for test in the following TWG categories: - Aviation (non-certified), cellular, general location/navigation, high precision, timing, networks, and space-based receivers - Each receiver should b...

Harmonization of texture and skid-resistance measurements.

DOT National Transportation Integrated Search

2008-09-30

Due to safety concerns associated with friction testing on both high and low-speed facilities, testing at variable speeds has been previously investigated by the Florida DOT. The American Society for Testing and materials (ASTM) has endorsed this con...

49 CFR 179.100-18 - Tests of tanks.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.100-18 Tests of tanks... having similar viscosity, at a temperature which shall not exceed 100 °F during the test; and applying...

Statewide pavement friction testing 2012.

DOT National Transportation Integrated Search

2012-11-01

In 2012, Dynatest conducted friction testing for the Wisconsin Department of Transportation (WisDOT) on a representative subset of its State Trunk Highway Network. Friction testing was performed at 3,394 sites in accordance with ASTM E274 using a Dyn...

A randomized controlled trial testing an adherence-optimized Vitamin D regimen to mitigate bone change in adolescents being treated for acute lymphoblastic leukemia.

PubMed

Orgel, Etan; Mueske, Nicole M; Sposto, Richard; Gilsanz, Vicente; Wren, Tishya A L; Freyer, David R; Butturini, Anna M; Mittelman, Steven D

2017-10-01

Adolescents with acute lymphoblastic leukemia (ALL) develop osteopenia early in therapy, potentially exacerbated by high rates of concurrent Vitamin D deficiency. We conducted a randomized clinical trial testing a Vitamin D-based intervention to improve Vitamin D status and reduce bone density decline. Poor adherence to home supplementation necessitated a change to directly observed therapy (DOT) with intermittent, high-dose Vitamin D3 randomized versus standard of care (SOC). Compared to SOC, DOT Vitamin D3 successfully increased trough Vitamin 25(OH)D levels (p = .026) with no residual Vitamin D deficiency, 100% adherence to DOT Vitamin D3, and without associated toxicity. However, neither Vitamin D status nor supplementation impacted bone density. Thus, this adherence-optimized intervention is feasible and effective to correct Vitamin D deficiency in adolescents during ALL therapy. Repletion of Vitamin D and calcium alone did not mitigate osteopenia, however, and new, comprehensive approaches are needed to address treatment-associated osteopenia during ALL therapy.

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.

Multiplex method for initial complex testing of antibodies to blood transmitted diseases agents.

PubMed

Poltavchenko, Alexander G; Nechitaylo, Oleg V; Filatov, Pavel V; Ersh, Anna V; Gureyev, Vadim N

2016-10-01

Initial screening of donors and population at high risk of infection with blood transmitted diseases involves a number of analyses using monospesific diagnostic systems, and therefore is expensive labor- and time-consuming process. The goal of this work is to construct a multiplex test enabling to carry out rapid initial complex testing at a low price. The paper describes a kit making it possible to detect simultaneously antibodies to six agents of the most significant blood transmitted diseases: HIV virus, hepatitis B and C viruses, cytomegalovirus, T. pallidum and T. gondii in blood products. The kit comprises multiplex dot-immunoassay based on plane protein arrays (immune chips) using colloidal gold conjugates and silver development. It provides an opportunity to carry out complex analysis within 70min at room temperature, and there is no need of well-qualified personnel. We compared laboratory findings of the kit with monospecific kits for ELISA produced by two Russian commercial companies. Dot-assay results correlate well with data obtained using commercial kits for ELISA. Furthermore, multiplex analysis is quicker and cheaper in comparison with ELISA and can be carried out in non-laboratory conditions. The kit for multiplex dot-immunoassay of antibodies to blood transmitted agents can significantly simplify initial complex testing. Copyright © 2016 Elsevier B.V. All rights reserved.

Quantum Dots: Proteomics characterization of the impact on biological systems

NASA Astrophysics Data System (ADS)

Pozzi-Mucelli, Stefano; Boschi, F.; Calderan, L.; Sbarbati, A.; Osculati, F.

2009-05-01

Over the past few years, Quantum Dots have been tested in most biotechnological applications that use fluorescence, including DNA array technology, immunofluorescence assays, cell and animal biology. Quantum Dots tend to be brighter than conventional dyes, because of the compounded effects of extinction coefficients that are an order of magnitude larger than those of most dyes. Their main advantage resides in their resistance to bleaching over long periods of time (minutes to hours), allowing the acquisition of images that are crisp and well contrasted. This increased photostability is especially useful for three-dimensional (3D) optical sectioning, where a major issue is bleaching of fluorophores during acquisition of successive z-sections, which compromises the correct reconstruction of 3D structures. The long-term stability and brightness of Quantum Dots make them ideal candidates also for live animal targeting and imaging. The vast majority of the papers published to date have shown no relevant effects on cells viability at the concentration used for imaging applications; higher concentrations, however, caused some issues on embryonic development. Adverse effects are due to be caused by the release of cadmium, as surface PEGylation of the Quantum Dots reduces these issues. A recently published paper shows evidences of an epigenetic effect of Quantum Dots treatment, with general histones hypoacetylation, and a translocation to the nucleus of p53. In this study, mice treated with Quantum Dots for imaging purposes were analyzed to investigate the impact on protein expression and networking. Differential mono-and bidimensional electrophoresis assays were performed, with the individuation of differentially expressed proteins after intravenous injection and imaging analysis; further, as several authors indicate an increase in reactive oxygen species as a possible mean of damage due to the Quantum Dots treatment, we investigated the signalling pathway of APE1/Ref1, a protein involved in the response to oxidative stress. Our results, although preliminary, suggest several interesting point of discussion on Quantum Dots imaging for in vivo diagnostic application, but also for a new therapeutic approach.

Comparison between Slow Components of HR and V[Combining Dot Above]O2 Kinetics: Functional Significance.

PubMed

Zuccarelli, Lucrezia; Porcelli, Simone; Rasica, Letizia; Marzorati, Mauro; Grassi, Bruno

2018-03-22

Aerobic exercise prescription is often based on a linear relationship between pulmonary oxygen consumption (V[Combining Dot Above]O2) and heart rate (HR). The aim of the present study was to test the hypothesis that during constant work rate (CWR) exercises at different intensities the slow component of HR kinetics occurs at lower work rate and is more pronounced that the slow component of V[Combining Dot Above]O2 kinetics. Seventeen male (age, 27±4yr) subjects performed on a cycle ergometer an incremental exercise to voluntary exhaustion and several CWR exercises: 1) moderate CWR exercises (MODERATE), below gas exchange threshold (GET); 2) heavy CWR exercise (HEAVY), at 45% of the difference between GET and V[Combining Dot Above]O2 peak (□); 3) severe CWR exercise (SEVERE), at 95% of Δ; 4) "HRCLAMPED" exercise in which work rate was continuously adjusted to maintain a constant HR, slightly higher than that determined at GET. Breath-by-breath V[Combining Dot Above]O2, HR and other variables were determined. In MODERATE, no slow component of V[Combining Dot Above]O2 kinetics was observed, whereas a slow component with a relative amplitude (with respect to the total response) of 24.8±11.0% was observed for HR kinetics. During HEAVY, the relative amplitude of the HR slow component was more pronounced than that for V[Combining Dot Above]O2 (31.6±11.2 and 23.3±9.0%, respectively). During HRCLAMPED the decrease in work rate (~14%) needed in order to maintain a constant HR was associated with a decreased V[Combining Dot Above]O2 (~10%). The HR slow component occurred at a lower work rate and was more pronounced than the V[Combining Dot Above]O2 slow component. Exercise prescriptions at specific HR values, when carried out for periods longer than a few minutes, could lead to premature fatigue.

78 FR 68360 - Unmanned Aircraft System Test Site Program

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-14

...-0061] Unmanned Aircraft System Test Site Program AGENCY: Federal Aviation Administration (FAA), DOT...'') test site program; response to comments. SUMMARY: On February 22, 2013 the FAA published and requested public comment on the proposed privacy requirements (the ``Draft Privacy Requirements'') for UAS test...

DOT&E

Science.gov Websites

of Defense on operational and live fire test and evaluation of Department of Defense weapon systems Guidance on the Validation of Models and Simulation used in Operational Test and Live Fire Assessments has

Quantum Dot Nanobioelectronics and Selective Antimicrobial Redox Interventions

NASA Astrophysics Data System (ADS)

Goodman, Samuel Martin

The unique properties of nanomaterials have engendered a great deal of interest in applying them for applications ranging from solid state physics to bio-imaging. One class of nanomaterials, known collectively as quantum dots, are defined as semiconducting crystals which have a characteristic dimension smaller than the excitonic radius of the bulk material which leads to quantum confinement effects. In this size regime, excited charge carriers behave like prototypical particles in a box, with their energy levels defined by the dimensions of the constituent particle. This is the source of the tunable optical properties which have drawn a great deal of attention with regards to finding appropriate applications for these materials. This dissertation is divided into multiple sections grouped by the type of application explored. The first sectoin investigates the energetic interactions of physically-coupled quantum dots and DNA, with the goal of gaining insight into how self-assembled molecular wires can bridge the energetic states of physically separated nanocrystals. Chapter 1 begins with an introduction to the properties of quantum dots, the conductive properties of DNA, and the common characterization methods used to characterize materials on the nanoscale. In Chapter 2 scanning tunneling measurements of QD-DNA constructs on the single particle level are presented which show the tunable coupling between the two materials and their resulting hybrid electronic structure. This is expanded upon in Chapter 3 where the conduction of photogenerated charges in QD-DNA hybrid thin films are characterized, which exhibit different charge transfer pathways through the constituent nucleobases depending on the energy of the incident light and resulting electrons. Complementary investigations of energy transfer mediated through DNA are presented in Chapter 4, with confirmation of Dexter-like transfer being facilitated through the oligonucleotides. The second section quantifies the use of cadmium telluride quantum dots as light-activated therapeutics for treating multi-drug resistant bacterial infectoins. A review of the physiological effects of cadmium chalcogenide quantum dots is first presented in Chapter 5 which provides a foundation for understanding the inherent toxicity of these materials. The phototoxic effect induced by CdTe quantum dots is then introduced in Chapter 6 showing the reduction in growth of gram-negative bacteria. Additional insight is provided in Chapter 7 which discusses the therapeutic mechanism and the oxygen-centered radical species which are formed by the application of light in aqueous media. The section closes with Chapter 8 describing efforts to improve the stability and bio-compatibility of the dots using various surface treatments, and shows that stability can be improved by the passivation of the quantum dots' anionic facets, though at the cost of overall radical generation.

Air Traffic Control Experimentation and Evaluation with the NASA ATS-6 Satellite: Volume 5. Multipath Channel Characterization Test

DOT National Transportation Integrated Search

1976-09-01

Results of aeronautical L-band multipath channel characterization tests are given. All tests were conducted between September 1974 and April 1975 as part of the U.S. DOT aeronautical technology test program. These tests were part of the international...

Magnetically optimized SERS assay for rapid detection of trace drug-related biomarkers in saliva and fingerprints.

PubMed

Yang, Tianxi; Guo, Xiaoyu; Wang, Hui; Fu, Shuyue; Wen, Ying; Yang, Haifeng

2015-06-15

New developments in the fields of human healthcare and social security call for the exploration of an easy and on-field method to detect drug-related biomarkers. In this paper, Au nanoparticles dotted magnetic nanocomposites (AMN) modified with inositol hexakisphosphate (IP6) were used as surface-enhanced Raman scattering (SERS) substrate to quickly monitor trace drug-related biomarkers in saliva and to on-site screen a trace drug biomarker in fingerprints. Due to inducing with an external magnet, such substrate presented a huge SERS activity, which has met the sensitivity requirement for assay to detect the drug biomarkers in saliva from the U.S. Substance Abuse and Mental Health Services Administration, and also the limit of detection for drug biomarker in fingerprint reached 100 nM. In addition, this AMN-based SERS assay was successfully conducted using a portable Raman spectrometer, which could be used to on-site and accurately differentiate between the smokers and drug addicts in near future. Copyright © 2015 Elsevier B.V. All rights reserved.

Atomic Clocks and Variations of the FIne Structure Constant

NASA Technical Reports Server (NTRS)

Prestage, John D.; Tjoelker, Robert L.; Maleki, Lute

1995-01-01

We describe a new test for possible variations of the fine structure constant alpha by comparisons of rates between clocks based on hyperfine transitions in alkali atoms with different atomic number Z. H-maser, Cs, and Hg(+) clocks have a different dependence on alpha via relativistic contributions of order (Z-alpha)(sup 2). Recent H-maser vs Hg(+) clock comparison data improve laboratory limits on a time variation by 100-fold to give dot-alpha less than or equal to 3.7 x 10(exp -14)/yr. Future laser cooled clocks (Be(+), Rb, Cs, Hg(+), etc.), when compared, will yield the most sensitive of all tests for dot-alpha/alpha.

Design and Experimental Study of a Current Transformer with a Stacked PCB Based on B-Dot.

PubMed

Wang, Jingang; Si, Diancheng; Tian, Tian; Ren, Ran

2017-04-10

An electronic current transformer with a B-dot sensor is proposed in this study. The B-dot sensor can realize the current measurement of the transmission line in a non-contact way in accordance with the principle of magnetic field coupling. The multiple electrodes series-opposing structure is applied together with differential input structures and active integrating circuits, which can allow the sensor to operate in differential mode. Maxwell software is adopted to model and simulate the sensor. Optimization of the sensor structural parameters is conducted through finite-element simulation. A test platform is built to conduct the steady-state characteristic, on-off operation, and linearity tests for the designed current transformer under the power-frequency current. As shown by the test results, in contrast with traditional electromagnetic CT, the designed current transformer can achieve high accuracy and good phase-frequency; its linearity is also very good at different distances from the wire. The proposed current transformer provides a new method for electricity larceny prevention and on-line monitoring of the power grid in an electric system, thereby satisfying the development demands of the smart power grid.

Design and Experimental Study of a Current Transformer with a Stacked PCB Based on B-Dot

PubMed Central

Wang, Jingang; Si, Diancheng; Tian, Tian; Ren, Ran

2017-01-01

An electronic current transformer with a B-dot sensor is proposed in this study. The B-dot sensor can realize the current measurement of the transmission line in a non-contact way in accordance with the principle of magnetic field coupling. The multiple electrodes series-opposing structure is applied together with differential input structures and active integrating circuits, which can allow the sensor to operate in differential mode. Maxwell software is adopted to model and simulate the sensor. Optimization of the sensor structural parameters is conducted through finite-element simulation. A test platform is built to conduct the steady-state characteristic, on-off operation, and linearity tests for the designed current transformer under the power-frequency current. As shown by the test results, in contrast with traditional electromagnetic CT, the designed current transformer can achieve high accuracy and good phase-frequency; its linearity is also very good at different distances from the wire. The proposed current transformer provides a new method for electricity larceny prevention and on-line monitoring of the power grid in an electric system, thereby satisfying the development demands of the smart power grid. PMID:28394298

"Captive Column" Crash Tests : Crash Testing of a Light Standard Luminaire Pole

DOT National Transportation Integrated Search

1981-03-01

Under contract No. DOT-FH-11-9606 the Nevada Department of Transportation (NDOT) conducted crash testing to study the capability of "Captive Column" light standard appurtenances under controlled conditions. The studies were precursors of actual on si...

49 CFR 179.220-23 - Test of tanks.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-23 Test of tanks. (a) Each.... The temperature of the pressurizing medium must not exceed 100 °F. during the test. The container must...

49 CFR 179.200-22 - Test of tanks.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.200-22 Test of tanks. (a) Each... having similar viscosity, of a temperature which shall not exceed 100 °F. during the test; and applying...

Detection of viral infections using colloidal quantum dots

NASA Astrophysics Data System (ADS)

Bentzen, Elizabeth L.; House, Frances S.; Utley, Thomas J.; Crowe, James E., Jr.; Wright, David W.

2006-02-01

Fluorescence is a tool widely employed in biological assays. Fluorescent semiconducting nanocrystals, quantum dots (QDs), are beginning to find their way into the tool box of many biologist, chemist and biochemist. These quantum dots are an attractive alternative to the traditional organic dyes due to their broad excitation spectra, narrow emission spectra and photostability. Quantum dots were used to detect and monitor the progession of viral glycoproteins, F (fusion) and G (attachment), from Respiratory Syncytial Virus (RSV) in HEp-2 cells. Additionally, oligo-Qdot RNA probes have been developed for identification and detection of mRNA of the N(nucleocapsid) protein for RSV. The use of quantum dot-FISH probes provides another confirmatory route to diagnostics as well as a new class of probes for monitoring the flux and fate of viral RNA RSV is the most common cause of lower respiratory tract infection in children worldwide and the most common cause of hospitalization of infants in the US. Antiviral therapy is available for treatment of RSV but is only effective if given within the first 48 hours of infection. Existing test methods require a virus level of at least 1000-fold of the amount needed for infection of most children and require several days to weeks to obtain results. The use of quantum dots may provide an early, rapid method for detection and provide insight into the trafficking of viral proteins during the course of infection.