Healthy individuals' perspectives on clinical research protocols and influences on enrollment decisions

BACKGROUND

Understanding the perspectives of healthy individuals is important ethically and for the advancement of science. We assessed perceptions of risk associated with research procedures, comparing views of healthy individuals with and without experience in clinical research, and the respondents' reported willingness to volunteer.

METHODS

Semistructured interviews and written surveys were conducted. Study participants were healthy individuals, half of whom were currently enrolled in clinical research and half of whom had no prior experience in clinical research. Participants were queried regarding seven "minimal risk" or "greater than minimal risk" protocol vignettes with procedures of three types: routine diagnostic tests, more burdensome (i.e., more effort or potential harm) diagnostic tests, and pharmacologic interventions. Views of influences on enrollment decisions were also assessed.

RESULTS

Most healthy individuals indicated that protocols with more burdensome or pharmacologic interventions were very risky (59%, 58%), as opposed to routine diagnostic test procedures (32%). Respondents' willingness to enroll in protocols varied by type of protocol (p value < .001) and was inversely correlated with risk assessments (regression coefficients from GEE = -0.4; -0.5; -0.7). The odds of healthy individuals with research experience expressing strong willingness to enroll in the depicted protocols were twice the odds of healthy individuals without research experience expressing the same level of willingness (OR = 2.0 95% CI: [1.1, 3.9]). Respondents did not assign risk categories as institutional review boards (IRBs) would, as indicated by low agreement (26%) between respondent and expert opinion on minimal risk protocols.

CONCLUSIONS

Perceptions of procedure risk appear to influence healthy individuals' willingness to enroll in protocols. Participants with experience in clinical research were far more likely to express willingness to enroll, a finding with important scientific and ethical implications. The lack of alignment between healthy individuals' views of protocol risk and IRB categorization warrants further study.

Perceptions of the Professional Development Value of Honorary Fellowship Award Experiences

OBJECTIVE

Professional societies engage in activities with the aim of nurturing highly talented early career members of their field. Little is known about the value of honorary fellowship awards given annually by professional societies. Following up on the only known prior study of this topic, authors queried fellowship awardees in one psychiatric society to better understand the perceived value of honorary fellowships and other outcomes, such as subsequent involvement in professional societies.

METHODS

The authors queried former participants in the Laughlin and Psychiatry Resident-In-Training Examination® (PRITE®) Programs regarding their fellowship experiences and their subsequent involvement in The American College of Psychiatrists and other psychiatry membership organizations. The authors obtained frequency data and analyzed responses using t-tests and chi-squared tests. Associations between the outcomes and demographic characteristics such as age, gender, and fellowship type was tested.

RESULTS

Responses were gathered from 143 individuals who had participated in the Laughlin Fellowship and 22 in the PRITE Fellowship. Respondents felt that that the fellowship experience had been helpful professionally. Laughlin fellows were older and more likely to have assumed a leadership role in professional organizations (60 % vs 36 %, p = 0.04). Laughlin fellows also more strongly endorsed professional recognition as a benefit at the time of receiving their award. Survey respondents reported increased participation in professional organizations and assumed leadership roles in The College and other professional organizations subsequent to the fellowship experience.

CONCLUSIONS

On the whole, fellows were generally positive about their experiences. Many respondents became involved with The College subsequent to their fellowship, but a larger proportion became involved with other organizations, including in leadership roles. Professional societies with early career programs such as the Laughlin Fellowship and the PRITE Fellowship appear to identify and support future leaders as intended, but these leaders may engage more with other professional societies.

Are individuals living with mental illness and their preferred alternative decision-makers attuned and aligned in their attitudes regarding treatment decisions?

BACKGROUND

Mental disorders account for considerable suffering and societal burden. Prospective alternative decision-makers may be engaged in helping make treatment decisions for those who live with serious mental disorders. Little is known about the ways in which alternative decision makers arrive at treatment recommendations and whether the perspectives of alternative decision makers and ill individuals are aligned.

METHODS

The authors queried community-dwelling individuals diagnosed with schizophrenia, anxiety, or mood disorders and their preferred alternative decision-makers on issues regarding treatment decisions and underlying ethically-salient perspectives using a written survey instrument. Complete data were obtained on 26 pairs (n = 52, total). Outcomes included perspectives on clinical decision-making and underlying values that may shape their life choices. Two-sided paired t-tests and graphical representations were used.

RESULTS

We found that preferred alternative decision-makers overall accurately predicted the views of ill individuals with respect to the role of the individual and of family in treatment decision making. Preferred alternative decision-makers slightly overestimated autonomy-related perspectives. The personal views of ill individuals and preferred alternative decision-makers were aligned with respect to different physical and mental disorders, except in relation to alcohol and substance use where alternative decision-makers placed greater emphasis on autonomy. Alignment was also discovered on underlying life values, except the role of spirituality which was greater among alternative decision-makers.

CONCLUSION

Preferred alternative decision-makers are an ethical safeguard to ensure the wellbeing and rights of seriously ill individuals. In this pilot study, preferred alternative decision makers were aligned with their ill family members concerning treatment-related decisions and underlying life values. Future research should continue to explore and clarify the views of ill individuals and alternative decision makers to determine the quality of this safeguard used in clinical settings.

Accelerated failure time model under general biased sampling scheme

Right-censored time-to-event data are sometimes observed from a (sub)cohort of patients whose survival times can be subject to outcome-dependent sampling schemes. In this paper, we propose a unified estimation method for semiparametric accelerated failure time models under general biased estimating schemes. The proposed estimator of the regression covariates is developed upon a bias-offsetting weighting scheme and is proved to be consistent and asymptotically normally distributed. Large sample properties for the estimator are also derived. Using rank-based monotone estimating functions for the regression parameters, we find that the estimating equations can be easily solved via convex optimization. The methods are confirmed through simulations and illustrated by application to real datasets on various sampling schemes including length-bias sampling, the case-cohort design and its variants.

Self-Assembled Silica Nanostructures: Simultaneous Discrimination of Handedness, Pitch and Diameter of Helical Silica Nanotubes

The left- and right-handed helical silica nanostructures were obtained with the aid of organic templates, the formation of the nanostructures might follow a co-operation self-assembly mechanism. The chirality of the organogel self-assemblies was successfully transcribed in to the silica. The helical pitch and pore size of the silica nanotubes sensitively depended on the optical purity of the neutral gelator in the reaction mixtures.

Attunement and alignment of people with schizophrenia and their preferred alternative decision-makers: An exploratory pilot study comparing treatment and research decisions

BACKGROUND

Schizophrenia is a serious mental disorder that may affect the decisional capacity, and as a consequence, preferred alternative decision-makers may be engaged to help with clinical care and research-related choices. Ideally, alternative decision-makers will seek to make decisions that fit with the views and preferences of the ill individual. Few data exist, however, comparing the views of alternative decision-makers to those of individuals with schizophrenia.

METHODS

We conducted a written survey with individuals with schizophrenia living in a community setting, and a parallel survey with the person whom the ill individual identified as being a preferred alternative decision-maker. Complete data were obtained on 20 pairs (n = 40, total). Domains queried included (a) burden, happiness, and safety of the ill individual and of his or her family in treatment and research decisions and (b) importance of ethical principles in every day life. Two-sided paired t-tests and graphical summaries were used to compare responses.

RESULTS

Individuals with schizophrenia and their linked preferred alternative decision-makers were attuned on four of six aspects of treatment decision-making and on all six aspects of research decision-making that we queried.

CONCLUSION

The preferred alternative decision-makers overall demonstrated attunement to the views of the ill individuals in this small study. Ill individuals and their preferred alternative decision-makers were aligned in their views of ethically-salient aspects of every day life. These novel findings suggest that alternative decision-makers identified by ill individuals may be able to guide choices based on an accurate understanding of the ill individuals' views and values.

Demonstrating Patterns in the Views Of Stakeholders Regarding Ethically-Salient Issues in Clinical Research: A Novel Use of Graphical Models in Empirical Ethics Inquiry

BACKGROUND

Empirical ethics inquiry works from the notion that stakeholder perspectives are necessary for gauging the ethical acceptability of human studies and assuring that research aligns with societal expectations. Although common, studies involving different populations often entail comparisons of trends that problematize the interpretation of results. Using graphical model selection - a technique aimed at transcending limitations of conventional methods - this report presents data on the ethics of clinical research with two objectives: (1) to display the patterns of views held by ill and healthy individuals in clinical research as a test of the study's original hypothesis and (2) to introduce graphical model selection as a key analytic tool for ethics research.

METHODS

In this IRB-approved, NIH-funded project, data were collected from 60 mentally ill and 43 physically ill clinical research protocol volunteers, 47 healthy protocol-consented participants, and 29 healthy individuals without research protocol experience. Respondents were queried on the ethical acceptability of research involving people with mental and physical illness (i.e., cancer, HIV, depression, schizophrenia, and post-traumatic stress disorder) and non-illness related sources of vulnerability (e.g., age, class, gender, ethnicity). Using a statistical algorithm, we selected graphical models to display interrelationships among responses to questions.

RESULTS

Both mentally and physically ill protocol volunteers revealed a high degree of connectivity among ethically-salient perspectives. Healthy participants, irrespective of research protocol experience, revealed patterns of views that were not highly connected.

CONCLUSION

Between ill and healthy protocol participants, the pattern of views is vastly different. Experience with illness was tied to dense connectivity, whereas healthy individuals expressed views with sparse connections. In offering a nuanced perspective on the interrelation of ethically relevant responses, graphical model selection has the potential to bring new insights to the field of ethics.

Informal health care practices of residents: "curbside" consultation and self-diagnosis and treatment

OBJECTIVE

The authors explore the experiences of residents with respect to informal care related to personal health, including "curbside consultation," self-diagnosis, and self-prescription-self-care practices that run counter to ethical guidelines in medicine.

METHODS

Residents at one medical school completed a written survey regarding their personal health care practices, including their experiences in seeking or providing informal consultation, self-diagnosis, and self-prescribing. The authors obtained frequency data and analyzed responses via cross-tabulation. They used logistic regression models to assess the association of reported informal care practices and potential confounders, such as age, gender, and training program.

RESULTS

One hundred and fifty-five residents volunteered (71 % response rate). Most respondents had sought health care formally (70 %), and more had sought informal care in the previous 12 months (80 %). Of those who had pursued informal care, 90 % endorsed having requested a physical exam, a laboratory test, or a medication prescription from an attending, resident, or medical student. Respondents (28 %) commonly endorsed prescribing medication for themselves. Most respondents (90 %) reported being approached for informal care at least once in the previous year, including 84 % who were approached for prescriptions and 22 % who were approached by attending physicians. Main reasons endorsed for informal care seeking related to busy schedules and to cost and confidentiality advantages. Psychiatry residents reported using both formal and informal channels for personal health care, and 31 % acknowledged prescribing medications for themselves.

CONCLUSIONS

Informal care was a common practice among the residents in this study. Residents reported time constraints as the greatest influence on informal care seeking, rather than reasons found in previous studies related to cost and quality of care, protection of confidentiality, or prevention of embarrassment. The effects of informal care practices involving resident physicians warrant additional study.

Giving voice to study volunteers: comparing views of mentally ill, physically ill, and healthy protocol participants on ethical aspects of clinical research

MOTIVATION

Ethical controversy surrounds clinical research involving seriously ill participants. While many stakeholders have opinions, the extent to which protocol volunteers themselves see human research as ethically acceptable has not been documented. To address this gap of knowledge, authors sought to assess views of healthy and ill clinical research volunteers regarding the ethical acceptability of human studies involving individuals who are ill or are potentially vulnerable.

METHODS

Surveys and semi-structured interviews were used to query clinical research protocol participants and a comparison group of healthy individuals. A total of 179 respondents participated in this study: 150 in protocols (60 mentally ill, 43 physically ill, and 47 healthy clinical research protocol participants) and 29 healthy individuals not enrolled in protocols. Main outcome measures included responses regarding ethical acceptability of clinical research when it presents significant burdens and risks, involves people with serious mental and physical illness, or enrolls people with other potential vulnerabilities in the research situation.

RESULTS

Respondents expressed decreasing levels of acceptance of participation in research that posed burdens of increasing severity. Participation in protocols with possibly life-threatening consequences was perceived as least acceptable (mean = 1.82, sd = 1.29). Research on serious illnesses, including HIV, cancer, schizophrenia, depression, and post-traumatic stress disorder, was seen as ethically acceptable across respondent groups (range of means = [4.0, 4.7]). Mentally ill volunteers expressed levels of ethical acceptability for physical illness research and mental illness research as acceptable and similar, while physically ill volunteers expressed greater ethical acceptability for physical illness research than for mental illness research. Mentally ill, physically ill, and healthy participants expressed neutral to favorable perspectives regarding the ethical acceptability of clinical research participation by potentially vulnerable subpopulations (difference in acceptability perceived by mentally ill - healthy = -0.04, CI [-0.46, 0.39]; physically ill - healthy = -0.13, CI [-0.62, -.36]).

CONCLUSIONS

Clinical research volunteers and healthy clinical research-"naïve" individuals view studies involving ill people as ethically acceptable, and their responses reflect concern regarding research that poses considerable burdens and risks and research involving vulnerable subpopulations. Physically ill research volunteers may be more willing to see burdensome and risky research as acceptable. Mentally ill research volunteers and healthy individuals expressed similar perspectives in this study, helping to dispel a misconception that those with mental illness should be presumed to hold disparate views.

Do investigators understand ethically-important perspectives of clinical research participants?: a 'piggy-back' study of attunement and alignment in serious illness research

OBJECTIVE

The authors sought to compare investigators' predictions of clinical research participants' attitudes regarding ethically-important considerations in serious illness research with attitudes expressed by participants ("attunement"), to compare the personal attitudes of investigators and clinical research participants ("alignment"), and to explore the association between views expressed and covariates.

METHOD

The authors queried clinical research participants with either physical or mental illness (n=100) and faculty investigators conducting the clinical research protocols in which these participants were enrolled (n=77). Outcomes included attitudes regarding importance of medical research, attributes of seriously ill people in the research situation, and influences on enrollment decisions by seriously ill people. Generalized estimating equations and linear regression models were used.

RESULTS

Investigators underestimated the importance of research about physical illness, mental illness, and healthy people to participants (βPI=0.59, 95% CI [0.36, 0.83]; βMI=0.60, 95% CI [0.27, 0.92]; βH=0.93, 95% CI [0.57, 1.29]). Investigators incorrectly predicted that participants would assess seriously ill people as more vulnerable in the research situation than participants did (β=-0.68, 95% CI [-1.11, -0.25]). Investigators and participants were aligned on the importance of illness research. Participants expressed greater agreement than investigators regarding the influences of ill individuals indicative of will and cognition in their enrollment decisions (β=0.69, 95% CI [0.25, 1.13]).

CONCLUSIONS

Investigators are attuned to and aligned with research participants in many, but not all, respects. Investigators may bring a protective bias in their predictions of the vulnerabilities of ill volunteers.

A Unified Approach to Semiparametric Transformation Models under General Biased Sampling Schemes

We propose a unified estimation method for semiparametric linear transformation models under general biased sampling schemes. The new estimator is obtained from a set of counting process-based unbiased estimating equations, developed through introducing a general weighting scheme that offsets the sampling bias. The usual asymptotic properties, including consistency and asymptotic normality, are established under suitable regularity conditions. A closed-form formula is derived for the limiting variance and the plug-in estimator is shown to be consistent. We demonstrate the unified approach through the special cases of left truncation, length-bias, the case-cohort design and variants thereof. Simulation studies and applications to real data sets are presented.

An ultra-low power (ULP) bandage-type ECG sensor for efficient cardiac disease management

This paper proposed an ultra-low power bandage-type ECG sensor (the size: 76 × 34 × 3 (mm(3)) and the power consumption: 1 mW) which allows for a continuous and real-time monitoring of a user's ECG signals over 24h during daily activities. For its compact size and lower power consumption, we designed the analog front-end, the SRP (Samsung Reconfigurable Processor) based DSP of 30 uW/MHz, and the ULP wireless RF of 1 nJ/bit. Also, to tackle motion artifacts(MA), a MA monitoring technique based on the HCP (Half-cell Potential) is proposed which resulted in the high correlation between the MA and the HCP, the correlation coefficient of 0.75 ± 0.18. To assess its feasibility and validity as a wearable health monitor, we performed the comparison of two ECG signals recorded form it and a conventional Holter device. As a result, the performance of the former is a little lower as compared with the latter, although showing no statistical significant difference (the quality of the signal: 94.3% vs 99.4%; the accuracy of arrhythmia detection: 93.7% vs 98.7%). With those results, it has been confirmed that it can be used as a wearable health monitor due to its comfortability, its long operation lifetime and the good quality of the measured ECG signal.

A note on Using regression models to analyze randomized trials: asymptotically valid hypothesis tests despite incorrectly specified models

In the context of randomized trials, Rosenblum and van der Laan (2009, Biometrics 63, 937-945) considered the null hypothesis of no treatment effect on the mean outcome within strata of baseline variables. They showed that hypothesis tests based on linear regression models and generalized linear regression models are guaranteed to have asymptotically correct Type I error regardless of the actual data generating distribution, assuming the treatment assignment is independent of covariates. We consider another important outcome in randomized trials, the time from randomization until failure, and the null hypothesis of no treatment effect on the survivor function conditional on a set of baseline variables. By a direct application of arguments in Rosenblum and van der Laan (2009), we show that hypothesis tests based on multiplicative hazards models with an exponential link, i.e., proportional hazards models, and multiplicative hazards models with linear link functions where the baseline hazard is parameterized, are asymptotically valid under model misspecification provided that the censoring distribution is independent of the treatment assignment given the covariates. In the case of the Cox model and linear link model with unspecified baseline hazard function, the arguments in Rosenblum and van der Laan (2009) cannot be applied to show the robustness of a misspecified model. Instead, we adopt an approach used in previous literature (Struthers and Kalbfleisch, 1986, Biometrika 73, 363-369) to show that hypothesis tests based on these models, including models with interaction terms, have correct type I error.

Validation of reported predialysis nephrology care of older patients initiating dialysis

The Centers for Medicare and Medicaid Services (CMS) Medical Evidence Report (form CMS-2728) queries providers about the timing of the patient's first nephrologist consultation before initiation of dialysis. The monitoring of disease-specific goals in the Healthy People 2020 initiative will use information from this question, but the accuracy of the reported information is unknown. We defined a cohort of 80,509 patients aged ≥67 years who initiated dialysis between July 2005 and December 2008 with ≥2 years of uninterrupted Medicare coverage as their primary payer. The primary referent, determined from claims data, was the first observed outpatient nephrologist consultation; secondary analyses used the earliest nephrology consultation, whether inpatient or outpatient. We used linear regression models to assess the associations among the magnitude of discrepant reporting and patient characteristics and we tested for any temporal trends. When using the earliest recorded outpatient nephrology encounter, agreement between the two sources of ascertainment was 48.2%, and the κ statistic was 0.29 when we categorized the timing of the visit into four periods (never, <6, 6-12, and >12 months). When we dichotomized the timing of first predialysis nephrology care at >12 or ≤12 months, accuracy was 70% (κ=0.36), but it differed by patient characteristics and declined over time. In conclusion, we found substantial disagreement between information from the CMS Medical Evidence Report and Medicare physician claims on the timing of first predialysis nephrologist care. More-specific instructions may improve reporting and increase the utility of form CMS-2728 for research and public health surveillance.

The effects of femoral graft placement on in vivo knee kinematics after anterior cruciate ligament reconstruction

Achieving anatomical graft placement remains a concern in Anterior Cruciate Ligament (ACL) reconstruction. The purpose of this study was to quantify the effect of femoral graft placement on the ability of ACL reconstruction to restore normal knee kinematics under in vivo loading conditions. Two different groups of patients were studied: one in which the femoral tunnel was placed near the anterior and proximal border of the ACL (anteroproximal group, n=12) and another where the femoral tunnel was placed near the center of the ACL (anatomic group, n=10) MR imaging and biplanar fluoroscopy were used to measure in vivo kinematics in these patients during a quasi-static lunge. Patients with anteroproximal graft placement had up to 3.4mm more anterior tibial translation, 1.1mm more medial tibial translation and 3.7° more internal tibial rotation compared to the contralateral side. Patients with anatomic graft placement had motion that more closely replicated that of the intact knee, with anterior tibial translation within 0.8mm, medial tibial translation within 0.5mm, and internal tibial rotation within 1°. Grafts placed anteroproximally on the femur likely provide insufficient restraint to these motions due to a more vertical orientation. Anatomical femoral placement of the graft is more likely to reproduce normal ACL orientation, resulting in a more stable knee. Therefore, achieving anatomical graft placement on the femur is crucial to restoring normal knee function and may decrease the rates of joint degeneration after ACL reconstruction.

An equatorial pacific ocean source of atmospheric mercury

Pronounced increases in total gaseous mercury (TGM) in the near surface marine atmosphere were found in the equatorial region (4 degrees N to 10 degrees S) of the Pacific Ocean at 160 degrees W. The atmospheric enhancement of TGM corresponded closely to sea-surface manifestations of equatorial upwelling as reflected in measured changes of temperature and nutrient concentrations as well as to variations of reactive mercury in surface seawater. The elevated atmospheric TGM levels most probably result from oceanic mercury evasion associated with upwelling and increased biological production that occurs in the equatorial Pacific Ocean.This evidence of sea-to-air mercury transfer supports model predictions of an oceanic source of atmospheric mercury and suggests that marine-derived mercury emissions should occur in other biologically productive regimes.

Comparison of particle size spectrum determination from images made using manual and automated image analysis

A digital processing method is described for determining the size spectra of sub-micron particles in natural water from transmission electron microscopy images of particles collected by ultracentrifugation, and is compared with traditional manual counting and size measurement methods. The processing method is based on the use of the MatLab Image Processing toolbox. The manual method was found to underestimate the population of particles smaller than 40 nm equivalent radius, primarily because of a "fatigue factor" in counting the very large numbers of particles in this size range. By contrast, the manual method produced higher particle counts of particles >50 nm radius, primarily because manual counters tend to group together particles as aggregates that digital processing indicates are not contiguous. The digitally-produced size spectrum for a river water sample was found to closely follow a power-series law down to the smallest particle size.

Endoscopic submucosal resection with double ligation technique for treatment of small rectal carcinoid tumors

BACKGROUND AND STUDY AIMS

It is difficult to achieve complete endoscopic resection of rectal carcinoid tumors without any procedure-related complications. In this study, we evaluated the efficacy and safety of endoscopic submucosal resection with double ligation (ESMR-DL) for the treatment of small rectal carcinoid tumors.

PATIENTS AND METHODS

Eleven rectal carcinoid tumors (in 11 patients) were resected by ESMR-DL between November 2001 and April 2004, using a conventional single-channel endoscope with an attached band-ligator device. The lesion was aspirated into the ligator device and an elastic band was placed around the base; a detachable snare was then used to ligate the stalk below the elastic band; and snare resection was performed above the elastic band. The resected specimens were examined with respect to size, histological atypia, depth of invasion, and the histological appearance of the resection margins.

RESULTS

All the lesions were excised completely without any complications. There was no tumor invasion beyond the submucosal layer and there was no evidence of atypia in any of the specimens. Tumor diameter varied from 2.0 mm to 10.0 mm (average 6.2 mm). None of the 11 specimens showed histopathological evidence of tumor involvement at the resection margins. There were no immediate or late complications (bleeding or perforation) after ESMR-DL. There was no local recurrence and there were no distant metastases in any patients during the mean follow-up period of 18 months.

CONCLUSION

Endoscopic submucosal resection with double ligation is a useful and safe method for the treatment of small rectal carcinoid tumors.

Effect of the Tube Diameter Distribution on the High-Temperature Structural Modification of Bundled Single-Walled Carbon Nanotubes

We present results of a systematic high-resolution transmission electron microscopy study of the thermal evolution of bundled single-walled carbon nanotubes (SWNTs) subjected to approximately 4-h high-temperature heat treatment (HTT) in a vacuum at successively higher temperatures up to 2200 degrees C. We have examined purified SWNT material derived from the HiPCO and ARC processes. These samples were found to thermally evolve along very different pathways that we propose depend on three factors: (1) initial diameter distribution, (2) concomitant tightness of the packing of the tubes in a bundle, and (3) the bundle size. Graphitic nanoribbons (GNR) were found to be the dominant high-temperature filament in ARC material after HTT = 2000 degrees C; they were not observed in any heat-treated HiPCO material. The first two major steps in the thermal evolution of HiPCO and ARC material agree with the literature, i.e., coalescence followed by the formation of multiwall carbon nanotubes (MWNTs). However, ARC material evolves to bundled MWNTs, while HiPCO evolves to isolated MWNTs. In ARC material, we find that the MWNTs collapse into multishell GNRs. The thermal evolution of these carbon systems is discussed in terms of the diameter distribution, nanotube coalescence pathways, C-C bond rearrangement, diffusion of carbon and subsequent island formation, as well as the nanotube collapse driven by van der Waals forces.

Thermal conversion of bundled carbon nanotubes into graphitic ribbons

High temperature heat treatment (HTT) of bundled single-walled carbon nanotubes (SWNTs) in vacuum ( approximately 10(-5) Torr) has been found to lead to the formation of two types of graphitic nanoribbons (GNRs), as observed by high-resolution transmission electron microscopy. Purified SWNT bundles were first found to follow two evolutionary steps, as reported previously, that is, tube coalescence (HTT approximately 1400 degrees C) and then massive bond rearrangement (HTT approximately 1600 degrees C), leading to the formation of bundled multiwall nanotubes (MWNTs) with 3-12 shells. At HTT > 1800 degrees C, we find that these MWNTs collapse into multishell GNRs. The first type of GNR we observed is driven by the collapse of diameter-doubled single-wall nanotubes, and their production is terminated at HTT approximately 1600 degrees C when the MWNTs also start to form. We propose that the collapse is driven by van der Waals forces between adjacent tubes in the same bundle. For HTT > 2000 degrees C, the heat-treated material is found to be almost completely in the multishell GNR form.

Developing products for personalized medicine: NIH Research Tools Policy applications

For innovators at academic or industrial institutions to develop personalized medicine products at the accelerated pace required, rapid access to state-of-the-art research tools and reagents are needed. Unreasonable restrictions or delays in the use of such tools may undermine the development of these customized diagnostics and therapeutic products designed to provide significant treatment benefits to patients who frequently do not benefit from traditional therapeutic approaches. In its funding agreements and its own internal research programs, the National Institutes of Health is implementing policies to facilitate the exchanges of these research tools and related resources.

Distribution and licensing of drug discovery tools--NIH perspectives

Now, more than ever, drug discovery conducted at industrial or academic facilities requires rapid access to state-of-the-art research tools. Unreasonable restrictions or delays in the distribution or use of such tools can stifle new discoveries, thus limiting the development of future biomedical products. In grants and its own research programs the National Institutes of Health (NIH) is implementing its new policy to facilitate the exchanges of these tools for research discoveries and product development.