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1.
Sci Eng Ethics ; 28(3): 27, 2022 06 02.
Article in English | MEDLINE | ID: mdl-35652979

ABSTRACT

In the United States National Science Foundation and the National Institutes of Health have mandated training STEM doctoral students in the ethical and responsible conduct of research to improve doctoral students' ethical decision-making skills; however, little is known about the process and factors that STEM faculty and graduate students use in their decision-making. This exploratory case study examined how four triads of chemistry faculty and their doctoral students recruited from three research universities in the eastern United States engaged in ethical decision-making on issues of authorship, assignment of credit, and plagiarism. A mixed-methods approach involving the administration of an online survey consisting of three open-ended case studies followed by a think-aloud interview was utilized. Participants were found to use analogical reasoning and base their decision-making on a common core set of considerations including fundamental principles, social contracts, consequences, and discussion with an advisor, often using prior personal experiences as sources. Co-authorship did not appear to impact the doctoral students' ethical decision-making. Gender may play a role in graduate students' decision-making; female doctoral students appeared to be less likely to consider prior experiences when evaluating the vignettes. Graduate students' lack of knowledge of the core issues in the responsible conduct of research, coupled with their lack of research experience, and inability to identify the core considerations may lead them to make bad judgments in specific situations. Our findings help explain the minimal impact that the current responsible conduct of research training methods has had on graduate students' ethical decision-making and should lead to the development of more effective approaches.


Subject(s)
Authorship , Decision Making , Faculty , Female , Humans , Morals , Students , United States
2.
Sci Eng Ethics ; 26(5): 2555-2599, 2020 10.
Article in English | MEDLINE | ID: mdl-32410102

ABSTRACT

This grounded study investigated the negotiation of authorship by faculty members, graduate student mentors, and their undergraduate protégés in undergraduate research experiences at a private research university in the northeastern United States. Semi-structured interviews using complementary scripts were conducted separately with 42 participants over a 3 year period to probe their knowledge and understanding of responsible authorship and publication practices and learn how faculty and students entered into authorship decision-making intended to lead to the publication of peer-reviewed technical papers. Herein the theoretical model for the negotiation of authorship developed through the analysis of these interviews is reported. The model identifies critical causal and intervening conditions responsible for the coping strategies faculty and students employ, which, in our study, appear to often produce unfortunate consequences for all involved. The undergraduate student researchers and their graduate student mentors interviewed in this study exhibited a limited understanding of authorship and the requirements for authorship in their research groups. The power differential between faculty and students, the students' limited epistemic development, the busy-ness of the faculty, and the faculty's failure to prioritize authorship have been identified as key factors inhibiting both undergraduate and graduate students from developing a deeper understanding of responsible authorship and publication practices. Implications for graduate education and undergraduate research are discussed, and strategies for helping all students to develop a deeper understanding of authorship are identified.


Subject(s)
Authorship , Universities , Faculty , Humans , Mentors , Students
3.
Anal Bioanal Chem ; 395(1): 1-4, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19609776
4.
Anal Bioanal Chem ; 391(7): 2373-6, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18528687
6.
Anal Bioanal Chem ; 384(5): 1029-33, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16477421
8.
J Biol Inorg Chem ; 8(5): 527-539, 2003 May.
Article in English | MEDLINE | ID: mdl-12764601

ABSTRACT

The complete solution structure of ferrocytochrome c in 30% acetonitrile/70% water has been determined using high-field 1D and 2D (1)H NMR methods and deposited in the Protein Data Bank with codes 1LC1 and 1LC2. This is the first time a complete solution protein structure has been determined for a protein in nonaqueous media. Ferrocyt c retains a native protein secondary structure (five alpha-helices and two omega loops) in 30% acetonitrile. H18 and M80 residues are the axial heme ligands, as in aqueous solution. Residues believed to be axial heme ligands in the alkaline-like conformers of ferricyt c, specifically H33 and K72, are positioned close to the heme iron. The orientations of both heme propionates are markedly different in 30% acetonitrile/70% water. Comparative structural analysis of reduced cyt c in 30% acetonitrile/70% water solution with cyt c in different environments has given new insight into the cyt c folding mechanism, the electron transfer pathway, and cell apoptosis.


Subject(s)
Cytochrome c Group/chemistry , Acetonitriles , Amino Acid Sequence , Animals , Energy Transfer , Horses , Hydrogen Bonding , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Sequence Data , Oxidation-Reduction , Protein Conformation , Protein Structure, Secondary , Protein Structure, Tertiary , Solutions , Structure-Activity Relationship , Water
9.
J Inorg Biochem ; 94(4): 381-5, 2003 Apr 01.
Article in English | MEDLINE | ID: mdl-12667710

ABSTRACT

Comparison of the 1H NMR spectra for guanidinated ferricyt c and chloro(terpyridine)platinum(II)-modified ferricyt c in 30% acetonitrile (ACN) solution with that for ferricyt c in 30% ACN is reported. The absence of the heme methyl proton resonances characteristic of the IV*-form (Lys-ligated) in the NMR spectrum of guanidinated ferricyt c in 30% ACN solution confirms that a lysine-ligated form of ferricyt c is produced in 30% ACN solution. The absence of the 8-methyl heme proton resonance of the V*-form in the NMR spectrum of chloro(terpyridine)platinum(II)-modified ferricyt c in 30% ACN solution demonstrates that a bis-His-ligated form of ferricyt c is produced in 30% ACN, not a hydroxide ligated form, as previously proposed. The revised assignment for the V* form of ferricyt c in mixed media explains differences between the exchange network we previously reported for ferricyt c in 30% ACN [Protein Sci. 10 (2001) 2291] as versus that reported by Dopner et al. at high pH [J. Am. Chem. Soc. 120 (1998) 11246]. Lys- and His-ligated forms are known to be produced in the presence of denaturants in protein folding studies of ferricyt c. Consequently, the exchange network between these non-native forms of ferricyt c in 30% ACN may have biological relevance for ferricyt c folding.


Subject(s)
Cytochrome c Group/chemistry , Histidine/chemistry , Lysine/chemistry , Organoplatinum Compounds/chemistry , Acetonitriles/chemistry , Animals , Cytochrome c Group/analysis , Guanidines/chemistry , Heme/chemistry , Horses , Ligands , Mitochondria, Heart/chemistry , Nuclear Magnetic Resonance, Biomolecular , Protein Conformation , Protons , Solutions
10.
J Biol Inorg Chem ; 8(1-2): 83-94, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12459902

ABSTRACT

This paper reports the first report of rapid, reversible direct electron transfer between a redox protein, specifically, horse myoglobin, and a solid electrode substrate in nonaqueous media and the spectroscopic (UV-vis, fluorescence, and resonance Raman) characterization of the relevant redox forms of myoglobin (Mb) in dimethyl sulfoxide (DMSO). In DMSO, the heme active site of metmyoglobin (metMb) appears to remain six-coordinate high-spin, binding water weakly. Changes in the UV-fluorescence spectra for metMb in DMSO indicate that the protein secondary structure has been perturbed and suggest that helix A has moved away from the heme. UV-vis and RR spectra for deoxyMb in DMSO suggest that the heme iron is six-coordinate low-spin, most likely coordinating DMSO. Addition of CO to deoxyMb in DMSO produces a single, photostable six-coordinate CO adduct. UV-vis and RR for Mb-CO in DMSO are consistent with a six-coordinate low-spin heme iron binding His93 weakly, if at all. The polarity of the distal heme pocket is comparable to that of the closed form of horse Mb-CO in aqueous solution, pH 7. Direct electron transfer between horse Mb and Au in DMSO solution was investigated by cyclic voltammetry. Mb exhibits stable and well-defined electrochemical responses that do not appear to be affected by the water content (1.3-7.5%). The electrochemical characteristics are consistent with a one-electron, quasi-reversible, diffusion-controlled charge transfer process at Au. E degrees for horse Mb in DMSO at Au is -0.241+/-0.005 V vs. NHE. The formal heterogeneous electron transfer rate constant, calculated from delta E(p) at 20 mV/s, is 1.7+/-0.5 x 10(-4) cm/s. The rate, which is unaffected by the presence of 1.3-7.5% water, is competitive with that previously reported for horse Mb in aqueous solution.


Subject(s)
Dimethyl Sulfoxide/chemistry , Myoglobin/chemistry , Animals , Binding Sites , Electrochemistry/methods , Electron Transport , Gold/chemistry , Heme/chemistry , Horses , Metmyoglobin/chemistry , Protein Structure, Secondary , Spectrum Analysis/methods , Water/chemistry
11.
Biomacromolecules ; 3(4): 846-9, 2002.
Article in English | MEDLINE | ID: mdl-12099832

ABSTRACT

Resonance Raman spectroscopy was used to interrogate the heme active site of horseradish peroxidase (HRP) lyophilized in the presence and absence of the lyoprotectant poly(ethylene glycol) (PEG; FW 5000; 0-80% w/w) suspended in acetone, chloroform, or acetonitrile. In aqueous solution, Fe(3+)HRP is characterized by a five-coordinate high-spin (5-c HS) heme system. The structure of the heme-active site of HRP in all solvents is perturbed by co-lyophilization of HRP with PEG. Heme active site structural changes are consistent with coordination of water in the distal axial coordination site of the ferric heme iron and disruption of the hydrogen-bond network when the protein is lyophilized in the presence of PEG (>or=60% w/w) in all of the solvent systems studied. Similar active site structural changes were previously observed for HRP in benzene and attributed to a change in the reaction mechanism for HRP in benzene. (Mabrouk, P. A.; Spiro, T. G. J. Am. Chem. Soc. 1998, 120, 10303-10309.) Thus, PEG is proposed to increase the catalytic activity of HRP in nonaqueous media by locking the heme active site into a structure that functions through an alternative catalytic pathway in nonaqueous media.


Subject(s)
Horseradish Peroxidase/chemistry , Polyethylene Glycols/pharmacology , Protein Renaturation/drug effects , Binding Sites/drug effects , Freeze Drying , Heme/chemistry , Horseradish Peroxidase/drug effects , Organic Chemicals , Protective Agents/pharmacology , Solvents , Spectrum Analysis, Raman
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