bluuebunny/crossref_metadata_2025_split huggingface dataset:
Malfunction of the da Vinci robotic system in urology
Authors: Chen Cheng‐Che , Ou Yen‐Chuan , Yang Cheng‐Kuang , Chiu Kun‐Yuan , Wang Shian‐Shiang , Su Chung‐Kuang , Ho Hao‐Chung , Cheng Chen‐Li , Chen Chuan‐Shu , Lee Jian‐Ri , Chen Wen‐Min 
Published: April 2012

Objectives:  To analyze the incidence of malfunction of the da Vinci robotic system in a single center and to provide potential solutions.Methods:  A total of 400 patients underwent da Vinci robotic urological surgery at Taichung Veterans General Hospital in Taichung, Taiwan, from December 2005 to April 2011. Episodes of malfunction of the robotic system were analyzed by period of operation, type of procedure, type of malfunction and management of the event.Results:  Overall, 14 cases of malfunction occurred (3.5% of the entire series). Among them, five (1.25%) occurred before the surgery and nine (2.25%) intraoperatively. Operative procedures included radical prostatectomy, bilateral pelvic lymph node dissection, dismembered pyeloplasty, partial nephrectomy, nephroureterectomy, and radical and partial cystectomies. Areas of malfunctions included the robotic arm system and joint (11/14), optical system (1/14), power system and connector (1/14), endoscopic instrument (1/14), and software (1/14). In 10 cases, the failure was recoverable, whereas in four cases there was a critical failure, requiring a conversion to standard laparoscopy in three of them, and the rescheduling of the surgery in one case.Conclusions:  The da Vinci robotic system is extremely reliable for use in urology. Malfunction is rare and the risk of critical failure is very low. Managing mechanical failure before or during the surgery is the key to maintaining the safety of patients undergoing robotic surgical procedures.
How much of reinforcement learning is working memory, not reinforcement learning? A behavioral, computational, and neurogenetic analysis
Authors: Collins Anne G. E. , Frank Michael J. 
Published: April 2012

AbstractInstrumental learning involves corticostriatal circuitry and the dopaminergic system. This system is typically modeled in the reinforcement learning (RL) framework by incrementally accumulating reward values of states and actions. However, human learning also implicates prefrontal cortical mechanisms involved in higher level cognitive functions. The interaction of these systems remains poorly understood, and models of human behavior often ignore working memory (WM) and therefore incorrectly assign behavioral variance to the RL system. Here we designed a task that highlights the profound entanglement of these two processes, even in simple learning problems. By systematically varying the size of the learning problem and delay between stimulus repetitions, we separately extracted WM‐specific effects of load and delay on learning. We propose a new computational model that accounts for the dynamic integration of RL and WM processes observed in subjects’ behavior. Incorporating capacity‐limited WM into the model allowed us to capture behavioral variance that could not be captured in a pure RL framework even if we (implausibly) allowed separate RL systems for each set size. The WM component also allowed for a more reasonable estimation of a single RL process. Finally, we report effects of two genetic polymorphisms having relative specificity for prefrontal and basal ganglia functions. Whereas the COMT gene coding for catechol‐O‐methyl transferase selectively influenced model estimates of WM capacity, the GPR6 gene coding for G‐protein‐coupled receptor 6 influenced the RL learning rate. Thus, this study allowed us to specify distinct influences of the high‐level and low‐level cognitive functions on instrumental learning, beyond the possibilities offered by simple RL models.
Category representation and generalization in the prefrontal cortex
Authors: Pan Xiaochuan , Sakagami Masamichi 
Published: April 2012

AbstractCategorization is a function of the brain that serves to group together items and events in our environments. Here we review the following important issues related to category representation and generalization: namely, where categories are presented in the brain, and how the brain utilizes categorical membership to generate new information. Accumulated experimental evidence shows that the prefrontal cortex (PFC) plays a critical role in category formation and generalization. We propose that prefrontal neurons abstract the commonality beyond individual stimuli, and categorize these based on their common meaning by ignoring their physical properties and learning to represent the boundaries between behaviorally significant categories. We also claim that a subgroup of prefrontal neurons simultaneously receives the category‐related information and specific property information (e.g. reward) associated with an exemplar, to form a category‐based representation of that property, and propagates it among stimuli of the same category, possibly reflecting a neural basis for category generalization in the PFC. These results suggest that the PFC is involved in representing abstract rules, and generating new information on the basis of previously acquired knowledge.
Model‐based learning and the contribution of the orbitofrontal cortex to the model‐free world
Authors: McDannald Michael A. , Takahashi Yuji K. , Lopatina Nina , Pietras Brad W. , Jones Josh L. , Schoenbaum Geoffrey 
Published: April 2012

AbstractLearning is proposed to occur when there is a discrepancy between reward prediction and reward receipt. At least two separate systems are thought to exist: one in which predictions are proposed to be based on model‐free or cached values; and another in which predictions are model‐based. A basic neural circuit for model‐free reinforcement learning has already been described. In the model‐free circuit the ventral striatum (VS) is thought to supply a common‐currency reward prediction to midbrain dopamine neurons that compute prediction errors and drive learning. In a model‐based system, predictions can include more information about an expected reward, such as its sensory attributes or current, unique value. This detailed prediction allows for both behavioral flexibility and learning driven by changes in sensory features of rewards alone. Recent evidence from animal learning and human imaging suggests that, in addition to model‐free information, the VS also signals model‐based information. Further, there is evidence that the orbitofrontal cortex (OFC) signals model‐based information. Here we review these data and suggest that the OFC provides model‐based information to this traditional model‐free circuitry and offer possibilities as to how this interaction might occur.
How can a Bayesian approach inform neuroscience?
Authors: O’Reilly Jill X. , Jbabdi Saad , Behrens Timothy E. J. 
Published: April 2012

AbstractIn this review we consider how Bayesian logic can help neuroscientists to understand behaviour and brain function. Firstly, we review some key characteristics of Bayesian systems – they integrate information making rational use of uncertainty, they apply prior knowledge in the interpretation of new observations, and (for several reasons) they are very effective learners. Secondly, we illustrate how some well‐known psychological phenomena including visual illusions, categorical perception and attention can be understood in terms of Bayesian inference. We also consider how formal models can clarify our understanding of psychological constructs, by giving a truly computational definition of psychological processes. Finally, we consider how probabilistic representations and hence Bayesian algorithms could be implemented by neural populations. In particular, we explore how different types of population coding may lead to different predictions about activity in both single‐unit and imaging studies, and draw a distinction in this context between the representation of parameters and implementation of computations.
Decomposing effects of dopaminergic medication in Parkinson’s disease on probabilistic action selection – learning or performance?
Authors: Smittenaar P. , Chase H. W. , Aarts E. , Nusselein B. , Bloem B. R. , Cools R. 
Published: April 2012

AbstractDopamine has long been implicated in reward‐based learning and the expression of such learned associations on performance. Robust evidence supports its effects on learning and performance, but teasing these apart has proved challenging. Here we have adapted a classic test of value‐based learning, the probabilistic selection task, to disentangle effects of dopamine on value‐based performance from effects on value‐based learning. Valence‐specific effects of dopamine on this specific task cannot be accounted for by modulation of learning, and therefore must reflect modulation of performance. We found that dopaminergic medication, consisting of levodopa and/or dopamine agonists taken at own dose, in 18 patients with mild Parkinson’s disease (Hoehn and Yahr < 2.5) potentiated reward‐based approach in terms of both accuracy and reaction times, while leaving punishment‐based avoidance unaffected. These data demonstrate that the effects of dopamine on probabilistic action selection are at least partly mediated by effects on the expression of learned associations rather than on learning itself, and help refine current models of dopamine’s role in reward.
Density‐dependent investment in costly anti‐predator defences: an explanation for the weak survival benefit of group living
Authors: Daly Derek , Higginson A. D. , Chen Dong , Ruxton G. D. , Speed M. P. 
Published: April 2012

Ecology Letters(2012)AbstractA central explanation for group living across animal taxa is the reduced rate of attack by predators. However, many field observations show a weak or non‐existent effect of group size onper capitamortality rates. Herein we resolve this apparent paradox. We found thatPieris brassicaelarvae defended themselves less readily when in groups than when alone, in that they were more reluctant to regurgitate in response to simulated attacks and produced less regurgitant. Furthermore, a simple model demonstrates that this reluctance was sufficient to cancel out the benefit from being in a group. This conditional strategy can be understood in terms of the costs and benefits of defences. For grouped individuals, defence is less often required because attack rates are lower and the costs of defence may be higher due to competition for resources. These phenomena are likely to be widespread in facultatively gregarious species that utilise anti‐predator defences.
An inherited virus influences the coexistence of parasitoid species through behaviour manipulation
Authors: Patot Sabine , Allemand Roland , Fleury Frédéric , Varaldi Julien 
Published: April 2012

Ecology Letters(2012)AbstractThe potential role of pathogens or parasites in maintaining species coexistence is well documented. However, the impact of vertically transmitted symbionts, that can markedly modify their host’s biology, is largely unknown. Some females of theDrosophilaparasitoidLeptopilina boulardiare infected with an inherited virus (LbFV). The virus forces females to lay supernumerary eggs in already parasitised hosts, thus allowing its horizontal transmission. Using two independent experimental procedures, we found that LbFV impacts inter‐specific competition betweenL. boulardiand the relatedL. heterotoma. WhileL. boulardirapidly outcompetesL. heterotomain the absence of the virus,L. heterotomawas able to maintain or even to eliminateL. boulardiin the presence of LbFV. By forcing females to superparasitise, LbFV induced egg wastage inL. boulardithus explaining its impact on the competition outcome. We conclude that this symbiont whose transmission isL. boulardi‐density‐dependant may affect the coexistence ofLeptopilinaspecies.
Fertile forests produce biomass more efficiently
Authors: Vicca S. , Luyssaert S. , Peñuelas J. , Campioli M. , Chapin F. S. , Ciais P. , Heinemeyer A. , Högberg P. , Kutsch W. L. , Law B. E. , Malhi Y. , Papale D. , Piao S. L. , Reichstein M. , Schulze E. D. , Janssens I. A. 
Published: April 2012

Ecology Letters (2012)AbstractTrees with sufficient nutrition are known to allocate carbon preferentially to aboveground plant parts. Our global study of 49 forests revealed an even more fundamental carbon allocation response to nutrient availability: forests with high‐nutrient availability use 58 ± 3% (mean ± SE; 17 forests) of their photosynthates for plant biomass production (BP), while forests with low‐nutrient availability only convert 42 ± 2% (mean ± SE; 19 forests) of annual photosynthates to biomass. This nutrient effect largely overshadows previously observed differences in carbon allocation patterns among climate zones, forest types and age classes. If forests with low‐nutrient availability use 16 ± 4% less of their photosynthates for plant growth, what are these used for? Current knowledge suggests that lower BP per unit photosynthesis in forests with low‐ versus forests with high‐nutrient availability reflects not merely an increase in plant respiration, but likely results from reduced carbon allocation to unaccounted components of net primary production, particularly root symbionts.
Differential utilization of ash phloem by emerald ash borer larvae: ash species and larval stage effects
Authors: Chen Yigen , Ulyshen Michael D. , Poland Therese M. 
Published: April 2012

Two experiments were performed to determine the extent to which ash species (black, green and white) and larval developmental stage (second, third and fourth instar) affect the efficiency of phloem amino acid utilization by emerald ash borer (EAB) Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) larvae.
EAB larvae generally utilized green ash amino acids more efficiently than those of the other two species. For example, the concentrations of only six (two essential) and seven (two essential) amino acids were lower in frass from EAB that fed upon black and white ash than in the corresponding phloem, respectively. By contrast, concentrations of 16 (eight essential) amino acids were lower in the frass from EAB that fed upon green ash than in the phloem. In addition, in green ash, the frass : phloem ratios of 13 amino acids were lower than their counterparts in black and white ash.
The concentrations of non‐essential amino acids glycine and hydroxylproline were greater in frass than in phloem when EAB fed on black ash, although not when EAB fed on green or white ash.
The concentration of total phenolics (a group of putative defensive compounds to EAB, expressed as antioxidant activity of acetone extraction) was high in EAB frass but even higher in the phloem samples when the data were pooled across ash species and EAB larval stages. This suggests EAB larvae may eliminate phenolics through a combination of direct excretion and enzymatic conversion of phenolics to nonphenolics before excretion. Because the ratio of frass total phenolics to phloem total phenolics in white ash was lower than the ratios in black and green ash, the ability to destroy phenolics or convert them to nonphenolics was greater when EAB larvae fed on white ash.
Fourth‐instar EAB extracted phloem amino acids, including threonine, more efficiently than third‐instar EAB. The different larval developmental stages of EAB did not differ in their apparent ability to destroy phenolics or convert them to nonphenolics.
Immediate radical cystectomy vs conservative management for high grade cT1 bladder cancer: is there a survival difference?
Authors: Badalato Gina M. , Gaya Josep M. , Hruby Gregory , Patel Trushar , Kates Max , Sadeghi Neda , Benson Mitchell C. , McKiernan James M. 
Published: April 2012

Study Type – Aetiology (individual cohort)Level of Evidence 2bWhat's known on the subject? and What does the study add?For patients with high grade (HG) non‐muscle invasive urothelial cell cancer (UCC) of the bladder, transurethral resection of bladder tumor (TURBT) in conjunction with induction and maintenance intravesical therapy is a commonly used treatment modality.Early cystectomy, although offering the best opportunity for cure, would in turn constitute overtreatment in some cases.Conservative management strategies, as opposed to radical surgery, are a viable treatment option within a well selected subset of patients with HG T1 UCC.OBJECTIVE
To determine whether a survival difference exists between patients with high grade (HG) cT1 urothelial cell carcinoma (UCC) receiving immediate radical cystectomy (IRC) as opposed to those choosing bladder‐sparing therapy.
PATIENTS AND METHODS
Between January 1990 and August 2010, 349 patients were retrospectively identified with a diagnosis of HG cT1 UCC of the bladder. Patients were divided into two groups: those who underwent IRC and those treated with conservative management (CM), consisting of transurethral resection of the bladder tumour (TURBT) and intravesical therapy. IRC was defined as surgery within 90 days of HG cT1 diagnosis with no intervening transurethral resection (TUR) or intravesical therapy (IVT). Trends in patient selection and cancer‐specific survival (CSS) were analyzed over consecutive decades.
The primary outcome was to compare CSS among patients during consecutive decades whereby management paradigms shifted from IRC to CM. The secondary outcome was to examine whether patient selection changed over time for each respective intervention.
RESULTS
One hundred and thirteen patients underwent IRC and 236 had CM. From 1990 to 1999, only 90 patients were diagnosed with HG cT1 disease, and a majority of patients (n= 54) underwent IRC. From 2000 to 2010, only 23% (59/259) of the patients with HG cT1 underwent IRC. Despite 42.3% more patients successfully maintaining their bladder in the long‐term, no difference in 5 year bladder CSS was noted between decades (77% vs 80% consecutively, P= 0.566). A subset analysis of risk factors for bladder cancer progression/recurrence demonstrated more patients with lymphovascular invasion (LVI) on TUR underwent IRC in the current era (13/59 (22.0%) vs 13/200 (6.5%), P < 0.001). These findings remain to be validated in prospective work at other institutions.
CONCLUSION
Conservative management strategies are a viable treatment option within a well selected subset of patients with HG cT1 UCC.
Effect of primary percutaneous coronary intervention on stress hyperglycaemia in myocardial infarction
Authors: McGregor A. K. , Leech N. , Purcell I. F. , Edwards R. 
Published: April 2012

Diabet. Med. 29, 1317–1320 (2012)AbstractAim  To measure the effect of primary percutaneous coronary intervention on stress hyperglycaemia induced by ST segment elevation myocardial infarction.Methods  We measured blood glucose before primary percutaneous coronary intervention and 1 h after intervention in all patients presenting with ST segment elevation myocardial infarction for 2 months in our unit. A paired t‐test was used for a statistical analysis.Results  From 157 patients accepted for primary percutaneous coronary intervention, 90 patients were included in the analysis. Blood glucose before intervention was 8.4 ± 2.46 mmol/l (mean ± SD) and after intervention was 7.9 ± 2.0 mmol/l (mean ± sd) (P = 0.003). In the subset of 15 patients with hyperglycaemia (glucose greater than 10 mmol/l), glucose before intervention was 12.7 ± 2.62 mmol/l (mean ± SD) and after intervention was 9.8 ± 3.42 mmol/l (mean ± sd) (P = 0.0002).Conclusions  Blood glucose in patients with ST segment elevation myocardial infarction is significantly lower after primary percutaneous coronary intervention and this reduction is most marked in patients with hyperglycaemia. Waiting for the stress response to diminish means that 11.1% of patients’ glucose levels fell below the treatment threshold of 10 mmol/l. Using the post‐intervention blood glucose level avoids the need for treatment with insulin in this population. Further randomized studies are warranted to investigate the impact on mortality and morbidity of administering insulin triggered by pre‐invention blood glucose vs. post‐intervention blood glucose.
INPPL1 is associated with the metabolic syndrome in men with Type 1 diabetes, but not with diabetic nephropathy
Authors: Hyvönen M. E. , Ihalmo P. , Forsblom C. , Thorn L. , Sandholm N. , Lehtonen S. , Groop P.‐H. 
Published: April 2012

Diabet. Med. 29, 1589–1595 (2012)AbstractAims  The metabolic syndrome is a frequent phenomenon in people with Type 1 diabetes and is associated with diabetic nephropathy. The aim of this study was to investigate if the INPPL1 (inositol polyphosphate phosphatase‐like 1) gene encoding lipid phosphatase SHIP2 is associated with the metabolic syndrome and diabetic nephropathy in Finnish people with Type 1 diabetes.Methods  Participants were selected from the FinnDiane study for this cross‐sectional study. The individuals were divided into controls without the metabolic syndrome (n = 1074) and cases with the metabolic syndrome (n = 1328), or into groups based upon their albumin excretion rate. Nine single‐nucleotide polymorphisms covering the INPPL1 gene +/− 20 kb were genotyped. The associations between the single‐nucleotide polymorphisms and outcome variables were analysed with the χ2 test and logistic regression.Results  Two INPPL1 single‐nucleotide polymorphisms, rs2276048 (silent mutation) and rs2276047 (intronic), were associated with the metabolic syndrome in men with odds ratios of 0.23 (95% CI 0.11–0.45, P = 2.1 × 10−5), and 0.37 (0.21–0.65, P = 0.001), adjusted for age, duration of diabetes and history of smoking. When both sexes were included, these associations were less significant. No association between the genotyped single‐nucleotide polymorphisms and diabetic nephropathy was observed.Conclusions  INPPL1 gene variants may contribute to susceptibility to the metabolic syndrome in men with Type 1 diabetes, but not to diabetic nephropathy.
Experiences of using blood glucose targets when following an intensive insulin regimen: a qualitative longitudinal investigation involving patients with Type 1 diabetes
Authors: Rankin D. , Cooke D. D. , Heller S. , Elliott J. , Amiel S. , Lawton J. ,   for the UK National Institute for Health Research (NIHR) Dose Adjustment for Normal Eating (DAFNE) Study Group
Published: April 2012

Diabet. Med. 29, 1079–1084 (2012)AbstractAims  Use of blood glucose targets is considered essential to help patients with Type 1 diabetes achieve tight glycaemic control following structured education. To foster effective use of blood glucose targets, we explored patients’ experiences and views of implementing clinically recommended blood glucose targets after attending a structured education programme promoting intensive insulin treatment.Methods  Repeat, in‐depth interviews with 30 patients with Type 1 diabetes recruited from Dose Adjustment for Normal Eating (DAFNE) courses in the UK. Data were analysed using an inductive, thematic approach.Results  Patients found use of blood glucose targets motivational. Targets enabled patients to identify problems with blood glucose control and prompted them to make insulin dose adjustments independently, or with assistance. However, patients tended to adapt or simplify targets over time to: make them more attainable and easy to remember; reduce risk of hypoglycaemia; and, mitigate feelings of failure when attempts to attain clinically defined targets were unsuccessful. Some patients were advised to use elevated targets to counter hypoglycaemia unawareness and required help from health professionals to determine when/if these should be reduced.Conclusions  Although blood glucose targets are an important component of diabetes self‐management, patients may adapt and personalize them over time, sometimes inadvertently, with a potentially detrimental impact on long‐term glycaemic control. Blood glucose targets should be regularly revisited during clinical reviews and revised/new targets agreed to accommodate patients’ concerns and difficulties. Other interventions may need to be considered to promote effective use of blood glucose targets.