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1.
Evolution ; 76(S1): 6-14, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34951705

RESUMO

On the occasion of the 75th anniversary of the Society for the Study of Evolution, I look back at the so-called "evolutionary synthesis," to which many of the Society's founders and prominent founding members were committed. An important plank in the synthesis platform had to do with the importance of selection relative to mutation. Of course, there is no evolutionary change without mutation, and no adaptive evolutionary change without selection. So how could selection be more important than mutation, or vice-versa? At issue was whether adaptive evolutionary change is initiated and directed by selection, or by the appearance of new advantageous variation. Proponents of the synthesis took the position that Darwin himself had defended, namely that adaptive evolutionary change is initiated and directed by natural selection on standing variation, no new variation, no mutation, required. Natural selection is, in this sense, not just "creative," but is the creative agent of evolutionary change. In taking this extreme position, proponents of the synthesis were reacting to the equally extreme position of Mendelian-mutationists, who held that adaptive evolutionary change always commences with, and is directed by, the appearance of new advantageous mutations, and for whom mutation is the creative agent of evolutionary change. I conclude with some comments on "relative significance" issues and controversies, and respects in which the relative significance issues at the heart of the synthesis persist.


Assuntos
Evolução Biológica , Seleção Genética , Mutação
2.
Eur Urol Focus ; 6(6): 1190-1194, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30661943

RESUMO

BACKGROUND: The European School of Urology (ESU) and EAU Section of Uro-Technology (ESUT) started hands-on-training (HOT) sessions in 2007 along with structured European Basic Laparoscopic Urological Skills (EBLUS) examinations in 2013. EBLUS includes an online theoretical course, HOT by expert tutors on a set of dry-lab exercises, and finally a standardised examination for skill assessment and certification. OBJECTIVE: To analyse the results and predictors of success from the EBLUS examinations that were conducted during the European Urology Residents Education Programme (EUREP) and other international and national dedicated ESU events. DESIGN, SETTING, AND PARTICIPANTS: ESU has been delivering EBLUS courses and examinations over the past 6 yr (2013-2018) in more than 40 countries worldwide. Trainees were asked about their laparoscopic background (procedures assisted/performed) and about the availability of HOT or simulator/box trainer in their facility. Apart from the online theoretical course, 4 HOT tasks [(1) peg transfer, (2) pattern cutting, (3) single knot tying, and (4) clip and cut] with its quality assessment of depth perception, bimanual dexterity, and efficiency were a part of the assessment and were considered critical to pass the EBLUS examination. RESULTS AND LIMITATIONS: A total of 875 EBLUS examinations were delivered (EUREP, n=385; other ESU events, n=490), with complete data available for 533 (61%) participants among which 295 (55%) passed the examinations. Pass rate increased on a yearly basis from 35% to 70% (p<0.001) and was similar between EUREP (56%) and other ESU/ESUT events (55%). The significant predictors of success were passing tasks 1 [odds ratio (OR): 869.9, 95% confidence interval (CI): 89.6-8449.0, p<0.001] and 2 (OR: 3045.0, 95% CI: 99.2-93 516.2, p<0.001) of the examinations. A limitation of EBLUS was its inability to provide more advanced training such as wet-lab or cadaveric training. CONCLUSIONS: Over the past few years more trainees have passed the European Basic Laparoscopic Urological Skills (EBLUS) examinations. Trainees who spend more time on laparoscopic procedures demonstrated a better performance and pass rate. We found almost no difference between the EBLUS results collected from EUREP and other ESU/ESUT events, which confirms the robustness of the training and examinations conducted worldwide. PATIENT SUMMARY: Training in laparoscopy helps trainees pass the European Basic Laparoscopic Urological Skills (EBLUS) examinations, reflected by an increase in the pass rate over the past 6 yr. Our results also confirm the robustness of EBLUS training and examinations worldwide.


Assuntos
Tecnologia Biomédica/educação , Competência Clínica , Avaliação Educacional , Laparoscopia/educação , Procedimentos Cirúrgicos Urológicos/educação , Urologia/educação , Europa (Continente) , Humanos , Faculdades de Medicina , Fatores de Tempo
3.
J Hist Biol ; 52(4): 705-731, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31571023

RESUMO

This is the second of a two-part essay on the history of debates concerning the creativity of natural selection, from Darwin through the evolutionary synthesis and up to the present. In the first part, I focussed on the mid-late nineteenth century to the early twentieth, with special emphasis on early Darwinism and its critics, the self-styled "mutationists." The second part focuses on the evolutionary synthesis and some of its critics, especially the "neutralists" and "neo-mutationists." Like Stephen Gould, I consider the creativity of natural selection to be a key component of what has traditionally counted as "Darwinism." I argue that the creativity of natural selection is best understood in terms of (1) selection initiating evolutionary change, and (2) selection directing evolutionary change, for example by creating the variation that it subsequently acts upon. I consider the respects in which both of these claims sound non-Darwinian, even though they have long been understood by supporters and critics alike to be virtually constitutive of Darwinism.


Assuntos
Evolução Biológica , Genética Populacional/história , Seleção Genética , História do Século XIX , História do Século XX
4.
BJU Int ; 123(4): 726-732, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30431700

RESUMO

OBJECTIVE: To evaluate the variability of subjective tutor performance improvement (Pi) assessment and to compare it with a novel measurement algorithm: the Pi score. MATERIALS AND METHODS: The Pi-score algorithm considers time measurement and number of errors from two different repetitions (first and fifth) of the same training task and compares them to the relative task goals, to produce an objective score. We collected data during eight courses on the four European Association of Urology training in Basic Laparoscopic Urological Skills (E-BLUS) tasks. The same tutor instructed on all courses. Collected data were independently analysed by 14 hands-on training experts for Pi assessment. Their subjective Pi assessments were compared for inter-rater reliability. The average per-participant subjective scores from all 14 proctors were then compared with the objective Pi-score algorithm results. Cohen's κ statistic was used for comparison analysis. RESULTS: A total of 50 participants were enrolled. Concordance found between the 14 proctors' scores was the following: Task 1, κ = 0.42 (moderate); Task 2, κ = 0.27 (fair); Task 3, κ = 0.32 (fair); and Task 4, κ = 0.55 (moderate). Concordance between Pi-score results and proctor average scores per participant was the following: Task 1, κ = 0.85 (almost perfect); Task 2, κ = 0.46 (moderate); Task 3, κ = 0.92 (almost perfect); Task 4 = 0.65 (substantial). CONCLUSION: The present study shows that evaluation of Pi is highly variable, even when formulated by a cohort of experts. Our algorithm successfully provided an objective score that was equal to the average Pi assessment of a cohort of experts, in relation to a small amount of training attempts.


Assuntos
Competência Clínica/normas , Laparoscopia/educação , Urologia/educação , Algoritmos , Percepção de Profundidade , Avaliação Educacional , Lateralidade Funcional , Humanos , Internato e Residência , Laparoscopia/normas , Reprodutibilidade dos Testes , Análise e Desempenho de Tarefas , Gravação em Vídeo
5.
Stud Hist Philos Sci ; 62: 31-41, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28583357

RESUMO

Narratives are about not only what actually happened, but also what might have. And narrative explanations make productive use of these unrealized possibilities. I discuss narrative explanation as a form of counterfactual, difference-making explanation, with a demanding qualification: the counterfactual conditions are historically or narratively (not merely logically or physically) possible. I consider these issues in connection with literary, historical and scientific narratives.

6.
J Phys Chem Lett ; 8(1): 188-192, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27973856

RESUMO

We report directly grown strongly adherent graphene on Co3O4(111) by carbon molecular beam epitaxy (C MBE) at 850 K and density functional theory (DFT) findings that the first graphene layer is reconstructed to fit the Co3O4 surface, while subsequent layers retain normal graphene structure. This adherence to the Co3O4 structure results from partial bonding of half the carbons to top oxygens of the substrate. This structure is validated by X-ray photoelectron spectroscopy and low-energy electron diffraction studies, showing layer-by-layer graphene growth with ∼0.08 electrons/carbon atom transferred to the oxide from the first graphene layer, in agreement with DFT. In contrast, for Cr2O3 DFT finds no strong bonding to the surface and C MBE on Cr2O3(0001) yields only graphite formation at 700 K, with C desorption above 800 K. Thus strong graphene-to-oxide charge transfer aids nucleation of graphene on incommensurate oxide substrates and may have implications for spintronics.

7.
J Hist Biol ; 49(4): 659-684, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27848059

RESUMO

This is the first of a two-part essay on the history of debates concerning the creativity of natural selection, from Darwin through the evolutionary synthesis and up to the present. Here I focus on the mid-late nineteenth century to the early twentieth, with special emphasis on early Darwinism and its critics, the self-styled "mutationists." The second part focuses on the evolutionary synthesis and some of its critics, especially the "neutralists" and "neo-mutationists." Like Stephen Gould, I consider the creativity of natural selection to be a key component of what has traditionally counted as "Darwinism." I argue that the creativity of natural selection is best understood in terms of (1) selection initiating evolutionary change, and (2) selection being responsible for the presence of the variation it acts upon, for example by directing the course of variation. I consider the respects in which both of these claims sound non-Darwinian, even though they have long been understood by supporters and critics alike to be virtually constitutive of Darwinism.


Assuntos
Evolução Biológica , Dissidências e Disputas/história , Seleção Genética , Animais , História do Século XIX , História do Século XX , Mutação
9.
Langmuir ; 32(11): 2601-7, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-26940024

RESUMO

The direct growth of hexagonal boron nitride (h-BN) by industrially scalable methods is of broad interest for spintronic and nanoelectronic device applications. Such applications often require atomically precise control of film thickness and azimuthal registry between layers and substrate. We report the formation, by atomic layer epitaxy (ALE), of multilayer h-BN(0001) films (up to 7 monolayers) on Co(0001). The ALE process employs BCl3/NH3 cycles at 600 K substrate temperature. X-ray photoelectron spectroscopy (XPS) and low energy electron diffraction (LEED) data show that this process yields an increase in h-BN average film thickness linearly proportional to the number of BCl3/NH3 cycles, with BN layers in azimuthal registry with each other and with the Co(0001) substrate. LEED diffraction spot profile data indicate an average BN domain size of at least 1900 Å. Optical microscopy data indicate the presence of some domains as large as ∼20 µm. Transmission electron microscopy (TEM) and ambient exposure studies demonstrate macroscopic and microscopic continuity of the h-BN film, with the h-BN film highly conformal to the Co substrate. Photoemission data show that the h-BN(0001) film is p-type, with band bending near the Co/h-BN interface. Growth of graphene by molecular beam epitaxy (MBE) is observed on the surface of multilayer h-BN(0001) at temperatures of 800 K. LEED data indicate azimuthal graphene alignment with the h-BN and Co(0001) lattices, with domain size similar to BN. The evidence of multilayer BN and graphene azimuthal alignment with the lattice of the Co(0001) substrate demonstrates that this procedure is suitable for scalable production of heterojunctions for spintronic applications.

10.
Stud Hist Philos Biol Biomed Sci ; 58: 33-40, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26806602

RESUMO

Narratives may be easy to come by, but not everything is worth narrating. What merits a narrative? Here, I follow the lead of narratologists and literary theorists, and focus on one particular proposal concerning the elements of a story that make it narrative-worthy. These elements correspond to features of the natural world addressed by the historical sciences, where narratives figure so prominently. What matters is contingency. Narratives are especially good for representing contingency and accounting for contingent outcomes. This will be squared with a common view that narratives leave no room for chance. On the contrary, I will argue, tracing one path through a maze of alternative possibilities, and alluding to those possibilities along the way, is what a narrative does particularly well.


Assuntos
Narração , Ciência/história , Animais , Evolução Biológica , História do Século XIX , História do Século XX , História do Século XXI , Narração/história , História Natural/história , Filosofia/história
11.
World J Urol ; 34(4): 479-84, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26245746

RESUMO

PURPOSE: Assessing construct, face and content validity of the camera handling trainer (CHT), a novel low-fidelity training device for 30° laparoscope navigation skills. METHODS: We developed a custom-designed box trainer with clinically based graphic targets. A total of 117 participants, stratified according to their previous experience (novice, competent, expert), took part to a CHT session and subsequently were asked to fill out a survey to assess the impact of the CHT on their 30° laparoscope navigation skills. Sixty of them were also studied for task performance during a 1-h session, with multiple time measurements. RESULTS: All participants, regardless of the previous experience, significantly improved their performance after the CHT session. Regarding construct validity, the mean task performance on the last measurement for novice group was found to be comparable to the mean first attempt of both competent (p = 0.12) and expert (p = 0.24) participants. All participants agreed that "the CHT is a valid training tool" and that "the CHT should be part of the regular dry laboratory training sessions", assessing both face and content validity. Limitations include the need for assessment of predictive validity. CONCLUSIONS: The CHT is a valid training tool for 30° laparoscope navigation and thus should be considered as one of the fundamental exercises during basic laparoscopic hands-on training sessions for urologists.


Assuntos
Competência Clínica , Simulação por Computador , Educação de Pós-Graduação em Medicina/métodos , Laparoscópios , Laparoscopia/educação , Interface Usuário-Computador , Gravação em Vídeo/instrumentação , Desenho de Equipamento , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
12.
Can J Urol ; 22(3): 7817-23, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26068632

RESUMO

INTRODUCTION: The principles of enhanced recovery after surgery (ERAS) protocols have been developed to optimize care and facilitate recovery after major surgery. The purpose of this systematic review is to present an up-to-date assessment of the perioperative cares in complex urological surgery from the available evidence and ERAS group recommendations. MATERIALS AND METHODS: Systematic searches of PubMed, Embase, Cochrane library and conference abstracts and bibliographies databases. RESULTS: A total of six studies were identified that met the inclusion criteria. Two examined the role of ERAS in radical cystectomy, and the rest examined its role in renal surgery (open, laparoscopic or partial nephrectomy). These studies demonstrated a reduction in duration of inpatient stays with no increase in morbidity in ERAS groups compared with traditional care. CONCLUSIONS: ERAS protocols can reduce the length of hospital stay after major urological surgery, without increasing morbidity or mortality.


Assuntos
Cistectomia , Deambulação Precoce , Nefrectomia , Assistência Perioperatória/métodos , Protocolos Clínicos , Estudos de Coortes , Cistectomia/efeitos adversos , Humanos , Tempo de Internação , Nefrectomia/efeitos adversos , Readmissão do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Expert Rev Anticancer Ther ; 12(4): 429-37, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22500680

RESUMO

Prostate cancer is the most common solid-organ cancer affecting the male population. Men with metastatic prostate cancer treated with androgen ablation therapy often respond rapidly, with improvement in bone pain and decreases in serum prostate-specific antigen. However, almost all patients progress to the castrate-resistant state and until recently chemotherapy was the only treatment available with proven survival benefit. Abiraterone is a new class of anti-androgen with proven survival benefit post-chemotherapy. In this review we discuss the characteristics of abiraterone and the clinical trials that led to its approval for the treatment of patients with prostate cancer.


Assuntos
Androstenóis/farmacologia , Antineoplásicos/uso terapêutico , Orquiectomia , Neoplasias da Próstata/tratamento farmacológico , Androstenos , Androstenóis/uso terapêutico , Ensaios Clínicos como Assunto , Humanos , Masculino , Metástase Neoplásica , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia
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