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1.
BJU Int ; 133(4): 451-459, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38062880

RESUMO

OBJECTIVE: To provide a summary of our initial experience and assess the impact of the Saline-Assisted Fascial Exposure (SAFE) technique on erectile function (EF), urinary continence, and oncological outcomes after Robot-Assisted Laparoscopic Radical Prostatectomy (RALP). PATIENTS AND METHODS: From January 2021 to July 2022, we included patients with a baseline Sexual Health Inventory for Men (SHIM) score of ≥17 and a high probability of extracapsular extension (ECE), ranging from 21% to 73%, as per the Martini et al. nomogram. A propensity score matching was carried out at a ratio of 1:2 between patients who underwent RALP + SAFE (33) and RALP alone (66). The descriptive statistical analysis is presented. The SAFE technique was performed using two approaches, transrectal guided by micro-ultrasound or transperitoneal. Its principle entails a low-pressure injection of saline solution in the periprostatic fascia to achieve an atraumatic dissection of the neural hammock. Potency was defined as a SHIM score of ≥17 and continence as no pads per day. RESULTS: At follow-up intervals of 6, 13, 26, and 52 weeks, the SHIM score differed significantly between the two groups, favouring the RALP + SAFE (P = 0.01, P < 0.001, P < 0.001, and P = 0.01, respectively). These results remained significant when the mean SHIM score was assessed. As shown by the cumulative incidence curve, EF rates were higher in the RALP + SAFE compared to the RALP alone group (log-rank P < 0.001). The baseline SHIM and use of the SAFE technique were independent predictors of EF recovery. CONCLUSIONS: The use of the SAFE technique led to better SHIM scores at 6, 13, 26, and 52 weeks after RALP in patients at high risk of ECE who underwent a partial NS procedure.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Robótica , Masculino , Humanos , Solução Salina , Resultado do Tratamento , Procedimentos Cirúrgicos Robóticos/métodos , Prostatectomia/métodos , Fáscia , Laparoscopia/métodos
2.
Contact Dermatitis ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831517

RESUMO

BACKGROUND: Machine learning (ML) offers an opportunity in contact dermatitis (CD) research, where with full clinical picture, may support diagnosis and patch test accuracy. OBJECTIVE: This review aims to summarise the existing literature on how ML can be applied to CD in its entirety. METHODS: Embase, Medline, IEEE Xplore, and ACM Digital Library were searched from inception to February 7, 2024, for primary literature reporting on ML models in CD. RESULTS: 7834 articles were identified in the search, with 110 moving to full-text review, and six articles included. Two used ML to identify key biomarkers to help distinguish between allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD), three used image data to distinguish between ACD and ICD, and one used clinical and demographical data to predict the risk of positive patch tests. All studies used supervision in their ML model training with a total of 49 704 patients across all data sets. There was sparse reporting of the accuracy of these models. CONCLUSIONS: Although the available research is still limited, there is evidence to suggest that ML has potential to support diagnostic outcomes in a clinical setting. Further research on the use of ML in clinical practice is recommended.

3.
Support Care Cancer ; 30(2): 1547-1555, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34536134

RESUMO

PURPOSE: Cancer patients and their caregivers are overwhelmed with features of uncertainty, fear, shock, worry, anxiety, sadness, and grief. To add on to their misery, the COVID-19 pandemic has severely afflicted the cancer care delivery. The study was conducted to observe the challenges faced by cancer patients and their caregivers and to formulate strategies for oncological setups to overcome those challenges. METHODS: After obtaining institutional ethical clearance, a descriptive cross-sectional study was conducted to observe the challenges faced by patients and their caregivers at the level of various domains (physical, logistic, psychological, socioeconomic, and spiritual) who visited the outpatient and inpatient department of cancer pain and palliative care unit. The results were expressed in absolute numbers. RESULTS: Major challenges encountered were suffering from physical symptoms like pain, nausea, vomiting, dyspnea (90%), postponement of cancer treatment (80%), fear of contracting COVID infection due to hospital visit (93.5%), lack of accommodation (70%), and lack of spiritual clarity and hope (50%). CONCLUSIONS: Major challenges faced by patients were in physical and psychological domains, and those by caregivers were in socioeconomic domains and handling physical symptoms of their patients. It is imperative to recognize and be cognizant of the challenges faced by cancer patients and their caregivers. Health care setups should formulate strategies to alleviate these challenges and provide holistic care to cancer patients. These strategies will hold in good stead for future pandemics also.


Assuntos
COVID-19 , Neoplasias , Cuidadores , Estudos Transversais , Humanos , Neoplasias/epidemiologia , Neoplasias/terapia , Pandemias , SARS-CoV-2
4.
Indian J Med Res ; 155(2): 232-242, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35946200

RESUMO

India has a high share in the global burden of chronic terminal illnesses. However, there is a lack of a uniform system in providing better end-of-life care (EOLC) for large patients in their terminal stage of life. Institutional policies can be a good alternative as there is no national level policy for EOLC. This article describes the important aspects of the EOLC policy at one of the tertiary care institutes of India. A 15 member institutional committee including representatives from various departments was formed to develop this institutional policy. This policy document is aimed at helping to recognize the potentially non-beneficial or harmful treatments and provide transparency and accountability of the process of limitation of treatment through proper documentation that closely reflects the Indian legal viewpoint on this matter. Four steps are proposed in this direction: (i) recognition of a potentially non-beneficial or harmful treatment by the physicians, (ii) consensus among all the caregivers on a potentially non-beneficial or harmful treatment and initiation of the best supportive care pathway, (iii) initiation of EOLC pathways, and (iv) symptom management and ongoing supportive care till death. The article also focuses on the step-by-step process of formulation of this institutional policy, so that it can work as a blueprint for other institutions of our country to identify the infrastructural needs and resources and to formulate their own policies.


Assuntos
Pacientes Internados , Assistência Terminal , Humanos , Índia/epidemiologia , Política Organizacional , Centros de Atenção Terciária
5.
Indian J Public Health ; 66(2): 109-112, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35859490

RESUMO

Background: Access to pain management has been recognized as a fundamental human right. Inadequate pain relief hampers the quality of life and has a physiological and psychosocial impact on the patient and caregivers. Inadequate pain relief remains the leading cause of suffering in hospitalized patients worldwide. Objective: The objective of this article is to provide adequate pain relief to hospitalized patients through proper assessment, treatment, and monitoring of pain by the trained health-care workers through a sustainable and effective institutional pain management policy. Methods: The formulation of pain management policy at a tertiary care teaching institute was conducted in three phases - Phase 1: need assessment by an open-label, uncontrolled, prospective observational study over 1 month period, Phase 2: teaching, training, and awareness of health-care workers, and Phase 3: constitution of the committee at the institute level with the formation of pain resource teams. Results: An open-label, prospective observational study conducted over 1 month revealed that among 814 hospitalized patients, 108 out of 235 (46%) patients in medical and 385 out of 579 (66.5%) patients in the surgical cohort had NRS score of ≥3, implying an inadequate pain relief even at 24 h following medical or surgical intervention, respectively. Conclusion: The provision of effective and adequate pain relief to hospitalized patients requires trained health-care workers and a uniform and structured pain management policy at the institutional level. Recognition and addressal of the barriers and challenges while framing an institutional pain policy is of utmost importance.


Assuntos
Hospitais de Ensino , Política Organizacional , Manejo da Dor , Centros de Atenção Terciária , Humanos , Índia , Estudos Prospectivos
6.
J Anaesthesiol Clin Pharmacol ; 38(1): 97-103, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35706626

RESUMO

Background and Aims: Intubation in head and neck carcinoma (HNC) is difficult due to many reasons. Various guidelines recommend strategies for airway management in such anticipated difficult airway cases. However, literature is limited on airway management planning as per the level of difficulty based on airway assessment in these patients. EL-Ganzouri risk index (EGRI) has been proposed to aid in making airway management plan in HNC cases by some authors. This retrospective study was conducted to look at the data related to the pre-anesthetic airway assessment and the airway management plan executed by the anesthesiologists in 1000 patients of HNC in the previous nearly four years in order to determine how the choices made conformed to EGRI scores. Material and Methods: Records of all the patients with oral cancer posted for surgery over four years from January 2014 to December 2017 were retrospectively analyzed for preoperative airway assessment using El Ganzouri risk index assessment (EGRI), the intraoperative technique for nasotracheal intubation, airway management plan, and any intraoperative complications. Results: The risk of predicted airway difficulty was low (EGRI <4) in 38 patients and was high in the rest. The EGRI score was higher in the FOB group [4-9] as compared to DL [2-3] and VL [1-6]. The patients with EGRI >7 were intubated awake and those with EGRI <7 were intubated under general anesthesia (79.8%). Overall, the technique of choice for intubation was fibreoptic bronchoscopy (54%) followed by video laryngoscopy (42.6%). Conclusion: The airway management plan used in a tertiary care cancer center conformed to the approach suggested by the multivariate El Ganzouri risk index (EGRI). EGRI appears to be a useful means to ascertain the appropriate strategies for intubation in head and neck cancer patients.

7.
J Assist Reprod Genet ; 38(7): 1641-1646, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33904010

RESUMO

Staff competency is a crucial component of the in vitro fertilization (IVF) laboratory quality management system because it impacts clinical outcomes and informs the key performance indicators (KPIs) used to continuously monitor and assess culture conditions. Contemporary quality control and assurance in the IVF lab can be automated (collect, store, retrieve, and analyze), to elevate quality control and assurance beyond the cursory monthly review. Here we demonstrate that statistical KPI monitoring systems for individual embryologist performance and culture conditions can be detected by artificial intelligence systems to provide systemic, early detection of adverse outcomes, and identify clinically relevant shifts in pregnancy rates, providing critical validation for two statistical process controls proposed in the Vienna Consensus Document; intracytoplasmic sperm injection (ICSI) fertilization rate and day 3 embryo quality.


Assuntos
Aprendizado Profundo , Escore de Alerta Precoce , Técnicas de Cultura Embrionária/métodos , Pessoal de Laboratório , Injeções de Esperma Intracitoplásmicas/métodos , Blastocisto/citologia , Blastocisto/fisiologia , Desenvolvimento Embrionário , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Pessoal de Laboratório/normas , Redes Neurais de Computação , Gravidez , Taxa de Gravidez
8.
Community Ment Health J ; 57(4): 771-776, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32852657

RESUMO

Today, the internet has become an important element in people's lives, and owing to internet access becoming widespread, it has resulted in internet addiction. It is a major concern amongst medical students aiming to develop into health professionals. The implications of this addiction as well as its association with sleep and depression affects their studies, impacts their career goals and has detrimental consequences for society as a whole. The objectives of this study were to assess the proportion of medical undergraduate students and interns with internet addiction (IA), depressive symptoms and poor sleep quality and to study the association of IA with sleep quality and depressive symptoms. A cross-sectional questionnaire-based study was carried out in a medical college in Delhi. Universal sample consisting of all the medical students from first to final year (n = 185) and interns (n = 37) enrolled during the time of the study were included. Sleep quality, internet addiction and depressive symptoms in these students was assessed using Pittsburgh Sleep Quality Index (PSQI) Young's Internet Addiction Test (YIAT) and Patient Health Questionnaire-9 (PHQ) respectively. The average YIAT score was 33.16 ± 15.68. Overall 18%, 59.9%, 46.8% of students scored above validated cutoff scores for internet addiction, poor sleep quality and depression respectively. Prevalence of IA among males and females were 20.4% and 12.9% respectively. Significant correlations were found between potential IA, sleep quality and depression (p < 0.001). The study concluded a strong correlation between IA, disturbed sleep quality and depression. Identifying medical students with potential IA is important because this addiction often coexists with other psychological problems. Thus timely remedial actions and tailored interventions are required to combat IA among medical students.


Assuntos
Comportamento Aditivo , Estudantes de Medicina , Comportamento Aditivo/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Feminino , Humanos , Índia/epidemiologia , Internet , Transtorno de Adição à Internet , Masculino , Sono
9.
Indian J Palliat Care ; 27(2): 319-329, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34511803

RESUMO

OBJECTIVES: Novel coronavirus (COVID-19) pandemic has brought to the fore various challenges faced by pain and palliative care physicians working in oncology setup all over the country. Cancer care has been afflicted a lot during the pandemic, with challenges faced by patients and their caregivers as well as the healthcare workers. The questionnaire based online survey was conducted to explore the personal challenges faced, strategies adopted and to compare the challenges between different oncology setups. MATERIALS AND METHODS: After obtaining institutional ethical clearance the online questionnaire prepared through Google forms was rolled out to pain and palliative care physicians working all over the country with the help of social media platforms. The results were expressed in absolute number, percentage and comparisons were made with the help of Fisher's exact test. RESULTS: Maximum challenges faced were the fear of carrying infection back home (91%), the possibility of attending to a COVID positive case in day to day clinical practice because of inadequate space and screening (62%) and limited services provided by NGO's during pandemic (71%). Strategies commonly adopted were the provision of necessary personal protective equipment (83%), the conduct of educational sessions for the task force members (67%), maximum utilization of available space in the hospital (85%) and stockpiling of necessary medications and equipment (75%). CONCLUSION: It is the need of the hour to formulate strong and effective strategies to overcome the challenges encountered by pain and palliative care physicians so that we are equipped in the future to deal with any kind of pandemics.

10.
Indian J Palliat Care ; 26(Suppl 1): S156-S159, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33088109

RESUMO

The coronavirus disease 2019 pandemic has shaken the health-care infrastructure worldwide and has led to enormous challenges for cancer patients. They are suffering on various fronts during this pandemic, especially the often overlooked ones such as logistic and socioeconomic. Through the case series, we have highlighted the various components of these challenges the cancer patients are facing and tried to emphasize that the health-care setups and government along with nongovernmental organizations have to come on the forefront to help the patients mitigate these challenges.

11.
Indian J Palliat Care ; 26(Suppl 1): S153-S155, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33088108

RESUMO

Palliative surgery forms an important pillar of palliative treatment to provide holistic care to cancer patients in the form of providing relief from pain, local control of disease, hemorrhage, and for the purpose of rehabilitation. During the COVID-19 pandemic, we report the successful management of two cases of colorectal cancer which came under the category of high priority and underwent palliative surgery to provide relief from pain.

12.
J Oral Maxillofac Surg ; 77(12): 2422-2430, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31442416

RESUMO

PURPOSE: Although oral maxillofacial surgeons (OMSs) carry high legal risk in malpractice lawsuits, data elucidating the reason behind those claims and their outcomes are scarce. The purpose of the present study was to characterize the trends, analyze the payouts, and determine the etiology of malpractice cases against OMSs. MATERIALS AND METHODS: A retrospective case series study was performed using the Westlaw database to access medical malpractice cases filed against OMSs from 1980 to 2017. The inclusion criterion was that the defendants had included an OMS. Two of us independently collected the demographic data, verdicts, payouts, and etiology of the litigation. RESULTS: The study sample included 183 cases adjudicated from 1980 to 2017. The results highlighted the temporal and geographic trends, payout information, and etiology of the cases. The total number of malpractice cases had decreased by 60% from 2011 to 2015 compared with the previous 5 years. The greatest incidence of malpractice cases filed per 100 practicing OMSs was in New York, followed by California and Massachusetts. Ruling in favor of the defendant OMS was noted in 55% of the cases, of the plaintiffs in 40% of the cases, and had reached a settlement before trial in 3% of the cases. In the cases in which the ruling had favored the plaintiff, the average payment was $812,449.08, with a median payment of $250,000.00 (range, $13,750.00 to $14,887,525.95). Extraction cases represented 53% of all malpractice litigations. Of these, 65% had been third molar extractions that had resulted in lingual nerve injury (26%), postoperative infection (17%), wrong site extractions (15%), and death or brain damage (10%), among other injuries. CONCLUSIONS: Approximately one half of the malpractice cases favored the defendant OMS. Most cases were third molar extractions resulting in injuries ranging from lingual nerve injury to death. Complementary data from insurance companies would be helpful to provide more specific analysis of the etiology and trends of the malpractice cases.


Assuntos
Imperícia , Cirurgiões Bucomaxilofaciais , Bases de Dados Factuais , Humanos , Massachusetts , Estudos Retrospectivos
13.
Stroke ; 48(4): 1098-1100, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28246277

RESUMO

BACKGROUND AND PURPOSE: Intraprocedural thrombosis poses a formidable challenge during neuroendovascular procedures because the risks of aggressive thromboembolic treatment must be balanced against the risk of postprocedural hemorrhage. The aim of this study was to identify predictors of ischemic stroke after intraprocedural thrombosis after stent-assisted coiling and pipeline embolization device placement. METHODS: A retrospective analysis of intracranial aneurysms treated with stent-assisted coiling or pipeline embolization device placement between 2007 and 2016 at 4 major academic institutions was performed to identify procedures that were complicated by intraprocedural thrombosis. RESULTS: Intraprocedural thrombosis occurred in 34 (4.6%) procedures. Postprocedural ischemic stroke and hemorrhage occurred in 20.6% (7/34) and 11.8% (4/34) of procedures complicated by intraprocedural thrombosis, respectively. Current smoking was an independent predictor of ischemic stroke. There was no statistically significant difference in the rate of ischemic stroke or postprocedural hemorrhage with the use of abciximab compared with the use of eptifibatide in treatment of intraprocedural thrombosis. CONCLUSIONS: Current protocols for treatment of intraprocedural thrombosis associated with placement of intra-arterial devices were effective in preventing ischemic stroke in ≈80% of cases. Current smoking was the only independent predictor of ischemic stroke.


Assuntos
Isquemia Encefálica/etiologia , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Fármacos Hematológicos/uso terapêutico , Aneurisma Intracraniano/terapia , Trombose Intracraniana , Complicações Intraoperatórias , Trombólise Mecânica/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Stents , Acidente Vascular Cerebral/etiologia , Angiografia Digital , Anticoagulantes/uso terapêutico , Isquemia Encefálica/epidemiologia , Embolização Terapêutica/estatística & dados numéricos , Procedimentos Endovasculares/estatística & dados numéricos , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Aneurisma Intracraniano/epidemiologia , Trombose Intracraniana/complicações , Trombose Intracraniana/diagnóstico por imagem , Trombose Intracraniana/epidemiologia , Trombose Intracraniana/terapia , Complicações Intraoperatórias/diagnóstico por imagem , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/terapia , Masculino , Trombólise Mecânica/estatística & dados numéricos , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Retrospectivos , Acidente Vascular Cerebral/epidemiologia
15.
J Res Med Sci ; 22: 127, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29259638

RESUMO

Pulmonary sequestration (PS) is a rare congenital malformation of the lower respiratory tract and is commonly complicated by recurrent infections and presents with respiratory failure. We report an atypical clinical presentation of postprandial abdominal pain and cramps in a patient with intralobar PS.

16.
Acta Neurochir (Wien) ; 158(10): 1845-8, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27520360

RESUMO

INTRODUCTION: Titanium fixation plates are routinely used for rigid fixation of bone flaps after craniotomy. In craniofacial surgery or after craniotomy involving orbitozygomatic osteotomies, these plates are occasionally removed because of infection, pain, protrusion, soft tissue erosion, and plate malfunction. However, plate removal because of pain and protrusion after craniotomy without orbitozygomatic osteotomy has rarely been reported. METHODS: A retrospective analysis of all patients who underwent removal of cranial fixation plates after craniotomy, performed by the senior authors at one institution between 2014 and 2016, was conducted. RESULTS: A total of 319 patients underwent bone flap fixation after craniotomy using cranial fixation plates between 2014 and 2016. Five of those patients (1.6 %) had their cranial plates removed because of pain and protrusion. An additional four patients had a cranial fixation plate removed during that time frame with the original craniotomy performed before 2014. All nine patients had immediate resolution of symptoms after plate removal. CONCLUSION: We report our experience with cranial fixation plate removal because of pain and protrusion in patients who underwent craniotomy without orbitozygomatic osteotomy, particularly frontotemporal craniotomy. In an attempt to reduce this complication, we recently stopped placing a full-size burr hole in the keyhole area of a frontotemporal craniotomy, eliminating the need for a titanium burr hole cover plate.


Assuntos
Placas Ósseas/efeitos adversos , Craniotomia/métodos , Dor Pós-Operatória/prevenção & controle , Adulto , Craniotomia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/etiologia , Estudos Retrospectivos , Titânio
17.
Acta Neurochir (Wien) ; 158(12): 2409-2414, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27757556

RESUMO

BACKGROUND: Moyamoya disease is a vascular disorder characterized by progressive stenosis of the internal carotid artery. The presentation, progression, treatment options, and post-operative clinical outcomes for elderly (60 and older) Moyamoya patients have never been reported. METHODS: A retrospective analysis of all patients who were diagnosed with Moyamoya disease by the senior authors between 1991 and 2016 was performed. Patients who were 60 years or older at the time of surgery or last follow-up were further evaluated. RESULTS: Seventy patients were diagnosed with probable or definite Moyamoya disease during the study period (1991-2016). Eight patients (11.4 %; six females: two males; median age 63; range, 60-71 years) were found to be 60 years or older at the time of surgery or last follow-up and were included in the study. All patients had a modified Rankin scale (mRS) of either one or two (median 1) pre-operatively. Six patients (75 %) underwent surgical treatment on a total on seven hemispheres. Post-surgery, one patient had an improved mRS score, three had no changes, and two had worsening in their mRS scores. Both patients who did not undergo surgical interventions suffered from intra-parenchymal hemorrhages post-diagnosis. CONCLUSIONS: Moyamoya disease is most commonly seen in young and middle-aged patients. Presentation in the elderly (defined as 60 years and older in this study) is rare, and has never been reported in the literature. In this study, both direct and indirect revascularization procedures demonstrated potential benefit in some of these patients, with stabilization of progressive symptoms.


Assuntos
Revascularização Cerebral/efeitos adversos , Doença de Moyamoya/cirurgia , Complicações Pós-Operatórias , Acidente Vascular Cerebral/etiologia , Idoso , Artéria Carótida Interna/cirurgia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Moyamoya/diagnóstico , Estudos Retrospectivos , Resultado do Tratamento
19.
Proc Biol Sci ; 282(1812): 20151041, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26180069

RESUMO

The competition for resources among cells, individuals or species is a fundamental characteristic of evolution. Biological all-pay auctions have been used to model situations where multiple individuals compete for a single resource. However, in many situations multiple resources with various values exist and single reward auctions are not applicable. We generalize the model to multiple rewards and study the evolution of strategies. In biological all-pay auctions the bid of an individual corresponds to its strategy and is equivalent to its payment in the auction. The decreasingly ordered rewards are distributed according to the decreasingly ordered bids of the participating individuals. The reproductive success of an individual is proportional to its fitness given by the sum of the rewards won minus its payments. Hence, successful bidding strategies spread in the population. We find that the results for the multiple reward case are very different from the single reward case. While the mixed strategy equilibrium in the single reward case with more than two players consists of mostly low-bidding individuals, we show that the equilibrium can convert to many high-bidding individuals and a few low-bidding individuals in the multiple reward case. Some reward values lead to a specialization among the individuals where one subpopulation competes for the rewards and the other subpopulation largely avoids costly competitions. Whether the mixed strategy equilibrium is an evolutionarily stable strategy (ESS) depends on the specific values of the rewards.


Assuntos
Evolução Biológica , Comportamento Competitivo , Recompensa , Teoria dos Jogos , Aptidão Genética , Modelos Biológicos , Reprodução
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