Practice Variation between Salaried and Fee-for-Service Surgeons for Lumbar Surgery.

OBJECTIVE: To examine differences in surgical practices between salaried and fee-for-service (FFS) surgeons for two common degenerative spine conditions. Surgeons may offer different treatments for similar conditions on the basis of their compensation mechanism. METHODS: The study assessed the practices of 63 spine surgeons across eight Canadian provinces (39 FFS surgeons and 24 salaried) who performed surgery for two lumbar conditions: stable spinal stenosis and degenerative spondylolisthesis. The study included a multicenter, ambispective review of consecutive spine surgery patients enrolled in the Canadian Spine Outcomes and Research Network registry between October 2012 and July 2018. The primary outcome was the difference in type of procedures performed between the two groups. Secondary study variables included surgical characteristics, baseline patient factors, and patient-reported outcome. RESULTS: For stable spinal stenosis (n = 2234), salaried surgeons performed statistically fewer uninstrumented fusion (p < 0.05) than FFS surgeons. For degenerative spondylolisthesis (n = 1292), salaried surgeons performed significantly more instrumentation plus interbody fusions (p < 0.05). There were no statistical differences in patient-reported outcomes between the two groups. CONCLUSIONS: Surgeon compensation was associated with different approaches to stable lumbar spinal stenosis and degenerative lumbar spondylolisthesis. Salaried surgeons chose a more conservative approach to spinal stenosis and a more aggressive approach to degenerative spondylolisthesis, which highlights that remuneration is likely a minor determinant in the differences in practice of spinal surgery in Canada. Further research is needed to further elucidate which variables, other than patient demographics and financial incentives, influence surgical decision-making.

Temporal analysis of complication rates of cervical spine surgery for degenerative spine disease between younger and older cohorts using the CSORN registry: Is age just a number?

STUDY DESIGN: An ambispective review of consecutive cervical spine surgery patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN) between January 2015 and September 2019. PURPOSE: To compare complication rates of degenerative cervical spine surgery over time between older (> 65) and younger age groups (< 65). More elderly people are having spinal surgery. Few studies have examined the temporal nature of complications of cervical spine surgery by patient age groups. METHODS: Adverse events were collected prospectively using adverse event forms. Binary logistic regression analysis was utilized to assess associations between risk modifiers and adverse events at the intra-, peri-operative and 3 months post-surgery. RESULTS: Of the 761 patients studied (age < 65, n = 581 (76.3%) and 65 + n = 180 (23.7%), the intra-op adverse events were not significantly different; < 65 = 19 (3.3%) vs 65 + = 11 (6.1%), p < 0.087. Peri-operatively, the < 65 group had significantly lower percentage of adverse events (65yrs (11.2%) vs. 65 + = (26.1%), p < 0.001). There were no differences in rates of adverse events at 3 months post-surgery (< 65 = 39 (6.7%) vs. 65 + = 12 (6.7%), p < 0.983). Less blood loss (OR = 0.99, p < 0.010) and shorter length of hospital stay (OR = 0.97, p < 0.025) were associated with not having intra-op adverse events. Peri-operatively, > 1 operated level (OR = 1.77, p < 0.041), shorter length of hospital stay (OR = 0.86, p < 0.001) and being younger than 65 years (OR = 2.11, p < 0.006) were associated with not having adverse events. CONCLUSION: Following degenerative cervical spine surgery, the older and younger age groups had significantly different complication rates at peri-operative time points, and the intra-operative and 3-month post-operative complication rates were similar in the groups.

'Take my kidneys but not my corneas'-Selective preferences as a hidden problem for 'opt-out' organ donation policy.

With aims to both increase organ supply and better reflect individual donation preferences, many nations worldwide have shifted from 'opt-in' to 'opt-out' systems for post-mortem organ donation (PMOD). In such countries, while a prospective donor's willingness to donate their organs/tissues for PMOD was previously ascertained-at least partially-by their having recorded positive donation preferences on an official register prior to death, this willingness is now presumed or inferred-at least partially-from their not having recorded an objection to PMOD-on an official organ donation register. Using evidence regarding the presence and prevalence of selective donation preferences, and via exploration of how appeals to donation preferences are used to both motivate and legitimate shifts to opt-out frameworks, this paper draws attention to a set of previously unexplored problems for opt-out organ donation arising in contexts where: (a) individuals demonstrate selective post-mortem organ/tissue donation preferences, (b) legislation provides prospective donors with the opportunity to selectively permit/refuse the donation of certain organs/tissues in line with these preferences. While selective preferences pose few problems for opt-in systems where a selective occasion is built into the process of signing the donor register, this is not the case for opt-out systems. The loss of this selective occasion can cause significant problems where appeals to preferences motivate/legitimate shifts to opt-out but evidence regarding variable preferences does not feed into determinations regarding organ/tissue exclusions. The nature of these problems depends on how the authorization aspect of 'opt-out' systems is framed (e.g. as presumed consent, deemed consent or, given the role of familial consent in many jurisdictions as consent in name only).

Nanoscale Vector Electric Field Imaging Using a Single Electron Spin.

The ability to perform nanoscale electric field imaging of elementary charges at ambient temperatures will have diverse interdisciplinary applications. While the nitrogen-vacancy (NV) center in diamond is capable of high-sensitivity electrometry, demonstrations have so far been limited to macroscopic field features or detection of single charges internal to the diamond itself. In this work, we greatly extend these capabilities by using a shallow NV center to image the electric field of a charged atomic force microscope tip with nanoscale resolution. This is achieved by measuring Stark shifts in the NV spin-resonance due to AC electric fields. We demonstrate a near single-charge sensitivity of ηe = 5.3 charges/√Hz and subelementary charge detection (0.68e). This proof-of-concept experiment provides the motivation for further sensing and imaging of electric fields using NV centers in diamond.

Variation in surgical treatment of degenerative spondylolisthesis in Canada: surgeon assessment of stability and impact on treatment.

INTRODUCTION: Controversy exists regarding the optimal surgical treatment of degenerative lumbar spondylolisthesis (DS). Not all DS patients are the same, and the degree to which inherent stability may dictate treatment is unknown. The purpose of this study was to determine the variability in surgical approach relative to surgeon classified stability. The secondary objective was to compare patient-reported outcomes (PROs) across different surgical techniques and grades of stability. METHODS: Patients prospectively enrolled from eleven tertiary care institutions and followed from 2015 to 2019. The surgical technique was at the surgeon's discretion. Surgeons were asked to grade the degree of instability based on the degenerative spondylolisthesis instability classification system (DSIC). DSIC categorizes three different types (I-stable, II-potentially unstable, and III-unstable). One-year changes in PROs were compared between each group. Multivariable regression was used to identify any characteristics that explained variability in treatment. RESULTS: There were 323 patients enrolled in this study. Surgeons' stability classification versus procedure [decompression alone (D)/decompression and posterolateral fusion (D-PL)/and decompression with posterior/transforaminal lumbar interbody fusion (D-PLIF/TLIF)] were as follows: type I (n = 91): D-41%/D-PL-13%/D-PLIF/TLIF-46%; type II (n = 175): D-23%/D-PL-17%/D-PLIF/TLIF-60%; and type III (n = 57):(D-0%/D-PL-14%/D-PLIF/TLIF-86%). Type I patients undergoing D-PL had some improvements in EQ-5D and NRS versus those undergoing D-PLIF/TLIF but otherwise there were no other significant differences between groups. Regression analysis demonstrated advanced age (OR = 1.06, CI 1.02-10.12) and type I (OR = 2.61, CI 1.17-5.81) were associated with receiving decompression surgery alone. CONCLUSIONS: There exists considerable variation in surgical management of DS in Canada. Given similar PROs in two of the three groups, there is potential to tailor surgical intervention and improve resource utilization.

The case against meta-consent: not only do Ploug and Holm not answer it, they make it even stronger.

In a recent article, I argued that Ploug and Holm's 'meta-consent' proposal should be rejected for biobank governance. This was because, although meta-consent is permissible, it is both burdensome and ethically omissible. There is no ethical reason why funders should undertake the additional costs. Ploug and Holm have sought to respond to these arguments. Here, it is noted that not only do they fail to adequately refuse the case against meta-consent, they fail to even engage with the arguments, either misunderstanding them or ignoring them. In their response, Ploug and Holm unwittingly provide the basis of an even stronger case against meta-consent. They argue that broad consent has a built in tendency to expire, while also holding that broad consent should be one of the options available in meta-consent. Meta-consent thus ends up being more like dynamic consent, but, arguably, even more burdensome and costly.

Opioid use trends in patients undergoing elective thoracic and lumbar spine surgery.

Background: Opioid use in North America has increased rapidly in recent years. Preoperative opioid use is associated with several negative outcomes. Our objectives were to assess patterns of opioid use over time in Canadian patients who undergo spine surgery and to determine the effect of spine surgery on 1-year postoperative opioid use. Methods: A retrospective analysis was performed on prospectively collected data from the Canadian Spine Outcomes and Research Network for patients undergoing elective thoracic and lumbar surgery. Self-reported opioid use at baseline, before surgery and at 1 year after surgery was compared. Baseline opioid use was compared by age, sex, radiologic diagnosis and presenting complaint. All patients meeting eligibility criteria from 2008 to 2017 were included. Results: A total of 3134 patients provided baseline opioid use data. No significant change in the proportion of patients taking daily (range 32.3%-38.2%) or intermittent (range 13.7%-22.5%) opioids was found from pre-2014 to 2017. Among patients who waited more than 6 weeks for surgery, the frequency of opioid use did not differ significantly between the baseline and preoperative time points. Significantly more patients using opioids had a chief complaint of back pain or radiculopathy than neurogenic claudication (p < 0.001), and significantly more were under 65 years of age than aged 65 years or older (p < 0.001). Approximately 41% of patients on daily opioids at baseline remained so at 1 year after surgery. Conclusion: These data suggest that additional opioid reduction strategies are needed in the population of patients undergoing elective thoracic and lumbar spine surgery. Spine surgeons can be involved in identifying patients taking opioids preoperatively, emphasizing the risks of continued opioid use and referring patients to appropriate evidence-based treatment programs.

Contexte: En Amérique du Nord, l'utilisation d'opioïdes a augmenté rapidement dans les dernières années. La prise d'opioïdes en période préopératoire est associée à plusieurs issues négatives. Cette étude visait à évaluer l'évolution des tendances dans l'utilisation d'opioïdes des patients canadiens ayant subi une chirurgie spinale, et de déterminer les effets de la chirurgie sur leur utilisation 1 an après l'opération. Méthodes: Une analyse rétrospective a été réalisée à partir de données recueillies de manière prospective par le Canadian Spine Outcomes and Research Network pour les patients ayant subi une chirurgie thoracique ou une chirurgie spinale élective. On a comparé l'utilisation autodéclarée d'opioïdes au début du suivi, avant la chirurgie et 1 an après la chirurgie. L'utilisation d'opioïdes au départ a été comparée selon le sexe, l'âge, le diagnostic radiologique et le motif de consultation. Entre 2008 et 2017, tous les patients satisfaisant aux critères d'admissibilités ont été inclus dans l'étude. Résultats: Au total, 3134 patients ont fourni des données sur leur prise d'opioïdes au début du suivi. Il n'y avait pas de changement significatif dans la proportion de patients utilisant quotidiennement (32,3 % à 38,2 %) ou occasionnellement (13,7 % à 22,5 %) des opioïdes entre les patients à l'étude avant 2014 et ceux à l'étude de 2014 à 2017. Parmi les patients qui ont attendu plus de 6 semaines avant la chirurgie, la fréquence de la prise d'opioïdes n'a pas changé de manière significative entre le début du suivi et la rencontre préopératoire. Une proportion significativement plus grande de patients qui utilisaient des opioïdes consultaient principalement pour des douleurs au dos ou une radiculopathie que pour une claudication neurogène (p < 0,001), et il y avait une proportion significativement plus grande de patients de moins de 65 ans qui utilisaient des opioïdes que de patients de 65 ans ou plus (p < 0,001). Environ 41 % des patients qui prenaient quotidiennement des opioïdes au départ le faisaient aussi 1 an après la chirurgie. Conclusion: Ces données suggèrent que des stratégies supplémentaires de réduction de l'utilisation d'opioïdes sont nécessaires pour les patients qui subissent une chirurgie thoracique ou une chirurgie spinale élective. Il est possible de demander aux chirurgiens spécialisés dans ce domaine de repérer les patients qui prennent des opioïdes avant l'opération, puisque l'utilisation prolongée comporte des risques, et de les aiguiller vers un programme de traitement adéquat et fondé sur des données probantes.

Consultation and Surgical Wait Times in Cervical Spondylotic Myelopathy.

BACKGROUND: Cervical spondylotic myelopathy (CSM) is the leading cause of spinal cord impairment. In a public healthcare system, wait times to see spine specialists and eventually access surgical treatment for CSM can be substantial. The goals of this study were to determine consultation wait times (CWT) and surgical wait times (SWT), and identify predictors of wait time length. METHODS: Consecutive patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN) prospective and observational CSM study from March 2015 to July 2017 were included. A data-splitting technique was used to develop and internally validate multivariable models of potential predictors. RESULTS: A CSORN query returned 264 CSM patients for CWT. The median was 46 days. There were 31% mild, 35% moderate, and 33% severe CSM. There was a statistically significant difference in median CWT between moderate and severe groups; 207 patients underwent surgical treatment. Median SWT was 42 days. There was a statistically significant difference in SWT between mild/moderate and severe groups. Short symptom duration, less pain, lower BMI, and lower physical component score of SF-12 were predictive of shorter CWT. Only baseline pain and medication duration were predictive of SWT. Both CWT and SWT were shorter compared to a concurrent cohort of lumbar stenosis patients (p <0.001). CONCLUSIONS: Patients with shorter duration (either symptoms or medication) and less neck pain waited less to see a spine specialist in Canada and to undergo surgical treatment. This study highlights some of the obstacles to overcome in expedited care for this patient population.

Temps d'attente pour obtenir une consultation et une intervention chirurgicale dans le cas de lamyélopathie spondylotique cervicale. Contexte : La myélopathie spondylotique cervicale (MSC) est la principale cause des troubles de la moelle épinière. Dans un régime public de santé, les temps d'attente pour voir des spécialistes et, le cas échéant, pour avoir accès à un traitement chirurgical dans le cas de la MSC peuvent être considérables. Cette étude comporte deux objectifs : d'une part, déterminer les temps d'attente pour une consultation (TAC) et pour une intervention chirurgicale (TAIC) ; d'autre part, identifier les variables prédictives des temps d'attente. Méthodes : C'est dans le cadre du Canadian Spine Outcomes and Research Network (CSORN) que cette étude observationnelle prospective a été effectuée. Y ont participé des patients vus un à la suite de l'autre entre mars 2015 et juillet 2017. À cet égard, nous avons utilisé la méthode de fractionnement des données (data-splitting technique) pour développer et valider à l'interne des modèles concernant nos variables prédictives. Résultats : Les données du CSORN montrent que 264 patients atteints de MSC sont parvenus à obtenir une consultation. Leur TAC médian a été de 46 jours. Sur ces 264 patients, 31 % étaient atteints d'une forme légère de MSC ; 35 %, d'une forme modérée ; et 33 %, d'une forme grave. Une différence statistique notable est apparue en ce qui regarde le TAC médian du groupe de patients atteints de la forme modérée de la maladie et celui du groupe de patients atteints de la forme grave. Notons par ailleurs que 207 patients ont pu subir une intervention chirurgicale. Leur TAIC médian a été de 42 jours. Une différence statistique notable est apparue entre les groupes de patients atteints des formes légère/modérée et celui incluant des patients atteints de la forme grave. Des symptômes de courte durée, moins de douleurs ressenties, de bas IMC et des scores plus bas au SF-12 en matière de santé physique ont constitué des variables prédictives d'un TAC plus court. Les seules variables ayant pu prédire les TAIC ont été le niveau de douleur avant traitement et la durée d'un traitement médical. Enfin, tant les TAC que les TAIC des patients atteints de MSC se sont révélés plus courts que ceux d'une cohorte de patients atteints de sténose du canal lombaire (p < 0,001) étudiée simultanément. Conclusions : En somme, les patients dont la durée des symptômes ou du traitement médical était plus courte, de même que ceux ayant moins souffert de cervicalgie, ont moins attendu au Canada pour voir un spécialiste de la moelle épinière et subir une intervention chirurgicale. Cette étude met donc en relief certains obstacles à une offre de services rapides pour cette catégorie de patients.

The biobank consent debate: Why 'meta-consent' is not the solution?

Over the past couple of decades, there has been an ongoing, often fierce, debate about the ethics of biobank participation. One central element of that debate has concerned the nature of informed consent, must specific reconsent be gained for each new use, or user, or is broad consent ethically adequate? Recently, Thomas Ploug and Søren Holm have developed an alternative to both specific and broad consent: what they call a meta-consent framework. On a meta-consent framework, participants can choose the type of consent framework they require, for different kinds of use, different types of user and so on. Meta-consent involves a distinctive kind of design of the consent process. Here it is argued, first, that although a meta-consent framework does not wrong participants, Ploug and Holm understate the likely costs and burdens of such a framework, so there are good practical reasons not to offer it. Second, although Ploug and Holm allude to some ethical considerations that might seem to ground an ethical argument for providing meta-consent, they do not offer any sound argument, and it does not wrong participants in any way to fail to offer them the opportunity to design their own consent process.

Spinal pain is prospectively associated with cardiovascular risk factors in girls but not boys (CHAMPS study-DK).

PURPOSE: To examine the prospective associations between spinal pain exposures and risk factors for cardiovascular disease in children and explore the mediating role of health-related physical activity. METHODS: Students were recruited from ten public primary schools. Each week from November 2008 to October 2010, parents reported spinal pain occurrences in their children via text messaging. Clustered cardiovascular risk was estimated with a composite score comprising fasting serum triglycerides, homeostasis assessment model-estimated insulin resistance (HOMA-IR), total to high-density lipoprotein cholesterol ratio, and systolic blood pressure. Additional outcomes were fasting serum insulin and glucose concentrations and body mass index categories. Associations were explored with multilevel mixed regression models and reported with beta coefficients (ß) and percent difference scores. All models were adjusted for potential confounders. RESULTS: Data from 1022 children (53% female) with mean ± SD age of 8.4 ± 1.4 years were included. Girls with spinal pain had greater clustered cardiovascular risk (ß [95% CI]; percent difference [95% CI] = .41 [.02-.80]; 3.3% [.2-6.4%]) than those without spinal pain. Similar outcomes were observed for log insulin (percent difference [95% CI] = 3.4% [.6-6.2%]) and log HOMA-IR = (percent difference [95% CI] = 3.8% [.4-7.3%]). Remaining associations between spinal pain and cardiovascular risk in girls were nonsignificant. There were no associations between spinal pain and cardiovascular risk in boys. Moderate-to-vigorous-intensity physical activity did not appear to mediate this relationship. CONCLUSION: These findings suggest a potentially important link between spinal pain and cardiovascular risk in girls that may be independent of health-related physical activity. These slides can be retrieved under Electronic Supplementary Material.

Pubertal development and growth are prospectively associated with spinal pain in young people (CHAMPS study-DK).

PURPOSE: To examine the prospective associations of pubertal development and linear growth with spinal pain frequency and duration in children. METHODS: We recruited students from 10 public primary schools. Over 42 months, pubertal development was assessed four times and categorized according to Tanner stages 1-5, and height was measured on seven occasions. Occurrences of spinal pain were reported weekly via text messaging. We constructed variables for spinal pain duration (total weeks with pain) and frequency (number of episodes). Potential associations between pubertal development and growth were examined with generalized estimating equations and reported with incident rate ratios (IRRs). All models were adjusted for potential confounders. RESULTS: Data from 1021 children (53% female; mean [SD] age = 9.4 [1.4] years), with median participation duration of 39 months, were included. Advancing pubertal development was associated with increased spinal pain duration (IRR [95% CI] = 1.90 [1.45, 2.49] to 5.78 [4.03, 8.29]) and frequency of pain episodes (IRR [95% CI] = 1.32 [1.07, 1.65] to 2.99 [2.24, 3.98]). Similar associations were observed for each 1-cm change in height in 6 months with spinal pain duration (IRR [95% CI] = 1.19 [1.15, 1.23]) and frequency (IRR [95% CI] = 1.14 [1.11, 1.17]). The relations between pubertal development and spinal pain, as well as growth and spinal pain, were largely independent. CONCLUSIONS: In young people, pubertal development and linear growth are likely to be independent risk factors for the development of spinal pain. Pubertal development demonstrates evidence of dose-response in its relationship with spinal pain. This knowledge may assist healthcare providers with clinical decision-making when caring for pediatric patients. These slides can be retrieved under Electronic Supplementary Material.

The ethics of biobanking: Assessing the right to control problem for broad consent.

The biobank consent debate is one with deeply held convictions on both the 'broad' and 'specific' side with little sign of resolution. Recently, Thomas Ploug and Soren Holm have developed an alternative to both specific and broad consent: a meta-consent framework. The aim here is to consider whether meta-consent provides a 'solution' to the biobank consent debate. We clarify what 'meta-consent' actually is (arguing that the label is a misnomer and 'consent à la carte' is more accurate). We identify problems with Ploug and Holm's arguments, and some challenges for meta-consent. We focus on whether there is any ethical obligation to provide consent à la carte. There may seem to be so, especially if we draw upon an unclear appeal to the ethical significance of 'respect for autonomy'. Similarly, there might seem to be an intuitive inference from the fact that ethically legitimate research requires informed consent to the conclusion that it thereby requires consent à la carte. It is shown that this line of inference is mistaken.

Nanomechanical Sensing Using Spins in Diamond.

Nanomechanical sensors and quantum nanosensors are two rapidly developing technologies that have diverse interdisciplinary applications in biological and chemical analysis and microscopy. For example, nanomechanical sensors based upon nanoelectromechanical systems (NEMS) have demonstrated chip-scale mass spectrometry capable of detecting single macromolecules, such as proteins. Quantum nanosensors based upon electron spins of negatively charged nitrogen-vacancy (NV) centers in diamond have demonstrated diverse modes of nanometrology, including single molecule magnetic resonance spectroscopy. Here, we report the first step toward combining these two complementary technologies in the form of diamond nanomechanical structures containing NV centers. We establish the principles for nanomechanical sensing using such nanospin-mechanical sensors (NSMS) and assess their potential for mass spectrometry and force microscopy. We predict that NSMS are able to provide unprecedented AC force images of cellular biomechanics and to not only detect the mass of a single macromolecule but also image its distribution. When combined with the other nanometrology modes of the NV center, NSMS potentially offer unparalleled analytical power at the nanoscale.

Biopsychosocial factors predict quality of life in thoracolumbar spine surgery.

PURPOSE: Surgical intervention is a treatment option for various spinal pathology but many patients report no improvement or even an exacerbation of symptoms like pain. This study examined the association of preoperative (pre-op) biopsychosocial risk factors with poor quality of life at 2 and 6 months using hierarchical models controlling demographic and medical variables. METHOD: Participants undergoing thoracolumbar spine surgery (N = 214) were provided with questionnaire packages to complete pre-op, at 2 and at 6-month postoperative clinical follow-ups (i.e., demographics, psychosocial measures, SF-12, medical, and clinical measures). The surgeon recorded surgical measures. RESULTS: Examining the pre-op period only, greater age and medication use (for back symptoms) were associated with poorer physical quality of life [physical component summary score (PCS)], while greater catastrophizing, depression, and lower social support were associated with poorer mental QoL [mental component summary score (MCS)]. Lower preoperative PCS, social support, and greater kinesiophobia were associated with diminished PCS at 2-month. Higher pre-op MCS and higher social support was associated with better MCS at 2-month. Poorer PCS at 6-month was associated with older age and low social support, while diminished MCS was associated with lower pre-op social support, MCS, and longer time in the operation room. Preoperative kinesiophobia partially mediated the relationship between pre-op PCS and 2-month PCS. Age partially mediated the relationship between pre-op PCS and at 6-month. For MCS, social support was the lone partial mediator of baseline MCS and both 2 and 6-month MCS. CONCLUSION: These results show that preoperative psychosocial variables are significantly associated with poorer postoperative health-related QoL outcomes following spinal surgeries, supporting a biopsychosocial pre-op care map.

When is a Choice not a Choice? 'Sham Offers' and the Asymmetry of Adolescent Consent and Refusal.

In some jurisdictions there is a puzzling asymmetry between consent and refusal, where, for some kinds of treatment, the adolescent patient has the power to permit her own treatment but her refusal does not have the same kind of normative significance as refusal of treatment by a competent adult. In this journal I recently offered a clarification and defence of this asymmetry in terms of a paternalistic justification of the sharing of normative powers between adolescents and other parties. Lawlor (2016) offers a number of objections to this account. Three of his objections can be dealt with quickly. But one of them is much more challenging: the asymmetry of consent and refusal entails a practice of making sham offers (offers that purport to be responsive to the patient's choices, but which, in fact, are not). They do not really offer a choice at all. Genuine offers seem to require a commitment to be symmetrically responsive to whatever decision outcome is reached by the recipient of the offer. When we reflect upon the way that offers can be made in complex social contexts, where different parties have a 'say' in what ought to be done, the symmetry of responsiveness need not apply. Offers can be genuine, without being symmetrically responsive. Contrary to the seemingly plausible objection, the asymmetry of consent and refusal does not entail sham offers, or the offer of 'sham choices'.

Misleading by Omission: Rethinking the Obligation to Inform Research Subjects about Funding Sources.

Informed consent requirements for medical research have expanded over the past half-century. The Declaration of Helsinki now includes an explicit positive obligation to inform subjects about funding sources. This is problematic in a number of ways and seems to oblige researchers to disclose information irrelevant to most consent decisions. It is argued here that such a problematic obligation involves an "informational fallacy." The aim in the second part of the paper is to provide a better approach to making sense of how a failure to inform about funding sources wrongs subjects: by making appeals to obligations to refrain from misleading by omission. This alternative approach-grounded in a general obligation to refrain from misleading, an obligation that is independent of informed consent-provides a basis for a norm that protects subjects' interests, without the informational fallacy. The approach developed here avoids the problems identified with the currently specified general obligation to inform about funding sources.

Transitional paternalism: how shared normative powers give rise to the asymmetry of adolescent consent and refusal.

In many jurisdictions, adolescents acquire the right to consent to treatment; but in some cases their refusals - e.g. of life-saving treatment - may not be respected. This asymmetry of adolescent consent and refusal seems puzzling, even incoherent. The aim here is to offer an original explanation, and a justification, of this asymmetry. Rather than trying to explain the asymmetry in terms of a variable standard of competence - where the adolescent is competent to consent to, but not refuse, certain interventions - the account offered here focuses more closely on the normative power to render actions permissible. Where normative powers are shared they can readily give rise to an asymmetry between consent and refusal. We then turn to why it is justifiable that normative powers be shared in adolescence. Transitional paternalism holds that the acquisition of normative powers by competent adolescents should not be an instant one, achieved in a single step, but that there should be a transitional period where paternalistic protection is rolled back, but not entirely withdrawn until a later date. Transitional paternalism could be implemented without generating the asymmetry between consent and refusal but, it is argued, the asymmetric version of transitional paternalism is to be preferred insofar as it offers a greater respect for the adolescent's decisions than the symmetrical alternative.

All-optical thermometry and thermal properties of the optically detected spin resonances of the NV(-) center in nanodiamond.

The negatively charged nitrogen-vacancy (NV(-)) center in diamond is at the frontier of quantum nanometrology and biosensing. Recent attention has focused on the application of high-sensitivity thermometry using the spin resonances of NV(-) centers in nanodiamond to subcellular biological and biomedical research. Here, we report a comprehensive investigation of the thermal properties of the center's spin resonances and demonstrate an alternate all-optical NV(-) thermometry technique that exploits the temperature dependence of the center's optical Debye-Waller factor.

Nanoscale detection of a single fundamental charge in ambient conditions using the NV- center in diamond.

Single charge nanoscale detection in ambient conditions is a current frontier in metrology that has diverse interdisciplinary applications. Here, such single charge detection is demonstrated using two nitrogen-vacancy (NV) centers in diamond. One NV center is employed as a sensitive electrometer to detect the change in electric field created by the displacement of a single electron resulting from the optical switching of the other NV center between its neutral (NV(0)) and negative (NV(-)) charge states. As a consequence, our measurements also provide direct insight into the charge dynamics inside the material.

Electronic properties and metrology applications of the diamond NV- center under pressure.

The negatively charged nitrogen-vacancy (NV-) center in diamond has realized new frontiers in quantum technology. Here, the optical and spin resonances of the NV- center are observed under hydrostatic pressures up to 60 GPa. Our results motivate powerful new techniques to measure pressure and image high-pressure magnetic and electric phenomena. Additionally, molecular orbital analysis and semiclassical calculations provide insight into the effects of compression on the electronic orbitals of the NV- center.