Best Surgical removal of the brain cyst neurosurgeons: TOP 58 doctors

Assoc Prof. Dr. D.Güçlühan GÜÇLÜ CV

Born in 1973 in Eskişehir.

Between 1997-2003, he completed his residency training in the Bakırköy Mazhar Osman Training And Research Hospital For Psychiatry,Neurology And Neurosurgery

In 2003, he started to work as a specialist in Bakırköy Sadi Konuk Training and Research Hospital as an Associate Professor and served until 2023.

6 book chapters 22 international and 9 national publications

Association Memberships

Turkish Neurosurgical Association

The European Association Of Neurosurgical Societies Society for Central Nervous System Surgery

Turkish Doctors Union

Turkish Neurosurgical Society Spinal and Peripheral Nerve Surgery Group

Turkish Neurosurgical Society Stereotactic and Functional Neurosurgery Teaching and Training Group,

Experience abroad

Continuing Medical Education Certificate 4- Day Comprehensive Interventional Pain Management Anatomical Course September 27-September 30, Hilton Head South Carolina USA 2007

Cleveland spine review hands on course, The Cleveland Clinic center for Spine Health (3 month) 2008

The 2nd CSRS Hands-On Cadaver Course Cervical Spine Decompression and Stabilization Techniques, Saint Louis University Schoof of Medicine Practical Anatomy & Surgical Education, Prof.Dr.K. Daniel Riew 2009

The Latest Techniques in Less-Invasive Spine Surgery, Saint Louis University School of Medicine Practical Anatomy & Surgical education, 2011

Spinal Deformity , training course, Saint Louis University School of Medicine ,director Prof.Dr. L.LENKE.2011

Advanced Course In Cerebral Aneurysms Hands-on Cadaver Workshop with Live Surgery & Life-Like Simulation Course Director Prof.Dr. Ali Krisht, MD Arkansas Neuroscience Institute 2013

International Training Course for Full-endoscopic Operations of the Lumbar, Thoracic and Cervical Spine, Richard Wolf Academy Prima Vista 2016

"Neuromodulation Applications in Low Back Pain and Cadaver Studies" course 2017

BASIC FIELD OF HEALTH SCIENCES BRAIN AND BORDER SURGERY

Education Information

expertise in medicine

1998 HOSPITALS/İSTANBUL BAKIRKÖY PROF.DR.MAZHAR OSMAN MENTAL HEALTH AND NERVE

26/March/2003

DISEASES EDUCATION AND RESEARCH. HOSPITAL

Title of the thesis: Analysis of axial traumatic spondylolisthesia using the finite element method (2003) Supervisor: (Mehmet Murat Hancı)

Undergraduate DOKUZ EYLÜL UNIVERSITY

1990 FACULTY OF MEDICINE/MEDICAL PR.

31/July/1996

Foreign Language Knowledge

English YÖKDİL, 05.03.2017, Score: 85.0

Administrative Duties

Clinical Administrative Officer2018 -2023 İSTANBUL BAKIRKÖY DR.SADİ KONUK EDUCATION RESEARCH HOSPITAL

Memberships to Scientific Organizations

Turkish Neurosurgery Society Stereotactic and Functional Neurosurgery Education and Training Group, Member, 2022

2. Turkish Neurosurgical Society Spinal and Peripheral Nerve Surgery Group, Member, 2019

3. Turkish Neurosurgery Society, Member, 2004

International education

International Training Course for Full-endoscopic Operations of the Lumbar, Thoracic and Cervical Spine,

education and cadaver , Friday, 10 June 2016 Department of Neurosurgery,

(International)

Spinal Deformity LIVE!, training course, Saint Louis University School of Medicine , Course, 10.03.2011 - 11.03.2011 (International)

The Latest Techniques in Less-Invasive Spine Surgery, Clinic , Saint Louis University School of Medicine

Practical Anatomy & Surgical education 3839 Lindell Boulevard St:Louis MO 63108, Course,

04.03.2011 -06.03.2011 (International)

THE 2nd CSRS Hands-On Cadaver Course Cervical Spine Decompression and Stabilization Techniques,

Clinical and Cadaver course, Saint Louis University School of Medicine Practical Anatomy & Surgical

Education 3839 Lindell Boulevard, St. Louis, MO 63108, Course, 29.01.2009 -31.01.2009 (International)

Cleveland spine review hands on course, clinic and cadaveric bird, The Cleveland Clinic center for Spine Health , Course, 16.07.2008 -22.07.2008 (International)

Istanbul University surgeonpasa medical faculty neurosurgery clinic, increasing knowledge and experience, Istanbul University surgeonpasa medical faculty neurosurgery clinic, Study, 12.01.2004 -12.06.2004 (National)

WORKS

Articles :

GÜÇLÜ DOĞAN GÜÇLÜHAN, SPIRIT EMOTION (2022). Efficacy and Safety of Microscopic Bilateral Decompression with Unilateral Laminectomy in Geriatric Lumbar Spinal Stenosis Surgery. Medical Journal of Bakırköy, 18(3), 323-329., Doi: 10.4274/BMJ.galenos.2022.2022.7-9

GÜÇLÜ DOĞAN GÜÇLÜHAN (2020). Atlas (C1) Fractures. Turkish Journal of Neurosurgery, 30(3), 322-328.

GÜÇLÜDOĞANGÜÇLÜHAN,ŞENELALPARSLAN (2018). Surgery in Lumbar Narrow Canal

Selection of Decompression Method. Turkish Journal of Neurosurgery, 28(2), 221-229.

GÜÇLÜ DOĞAN GÜÇLÜHAN, ŞENORMANCI ÖMER, GÜÇLÜ OYA, CIRAK MUSA, ŞENORMANCI GÜLİZ,

KÖKTÜRK FÜRUZAN (2017). Fear avoidance beliefs and quality of life quality after lumbar disc surgery. Journal of Cognitive-Behavioral Psychotherapy and Research, 6(1), 1-8., Doi: 10.5455/JCBPR.245356

GÜÇLÜ DOĞAN GÜÇLÜHAN, GÜNALDI ÖMÜR, ERDOĞAN UZAY, OFLUOĞLU ALI ENDER, POSTALCI

LÜTFİ ŞİNASİ, KEPOĞLU ÜMİT, ÇELİK HAYDAR (2014). Analysis of axis traumatic spondylolisthesis by finite element method. Journal of Turkish Spinal Surgery, 25(3), 175-182.

GÜÇLÜ DOĞAN GÜÇLÜHAN, ÖZTÜRK ONUR, CIRAK MUSA, CAN HALİL, ÜNAL TUĞRUL CEM, DOLAŞ

İLYAS, ÖZGEN UTKU, AYDOSELİ AYDIN, SENCER ALTAY (2022). A Series of Posttraumatic Midline Epidural Hematoma and Review of the Literature. Turkish Journal of Trauma and Emergency Surgery, 28(6), 805-811., Doi: 10.14744/tjtes.2020.28182 (Quarterly Slice=Q4)

GÜÇLÜ DOĞAN GÜÇLÜHAN (2022). Pediatric Lumbar Microdiscectomy. Medical Journal of Bakirkoy, 18(3), 330-335., Doi: 10.4274/BMJ.galenos.2022.2022.6-16

(2020).

Comprehensive Anatomic and Morphometric Analyzes of Triangular Working Zone for Transforaminal Endoscopic Approach in Lumbar Spine: A Fresh Cadaveric Study. World Neurosurgery, 138, 486-491., Doi: 10.1016/j.wneu.2020.02.160 (Quarter Slice=Q3)

GÖKER BURCU, GÜÇLÜ DOĞAN GÜÇLÜHAN, DOLAŞ İLYAS, ÖZGEN UTKU, ALTUNRENDE MUHITTIN EMRE, AKINCI AHMET TOLGAY, ŞENCAN FAHİR, AYDOSELİ AYDIN, CAN HALİL, SENCER ALTAY

(2020). Clinical study of decompressive craniectomy in children. Turkish Neurosurgery, 30(2), 225-230., Doi: 10.5137/1019-5149.JTN.27576-19.3 (Quarterly Slice=Q4)

CAN HALIL, DİREN FURKAN, PEKER BARIS, CENGİZ WITHOUT THE SHIRT, GÜÇLÜ DOĞAN GÜÇLÜHAN, KÜÇÜK CEYHUN, CIVELEK ERDİNÇ, AYDOSELİ AYDIN, SENCER ALTAY (2020). Morphometric

analysis of lumbar arteries and relationship with intervertebral discs\\', a study of surgical anatomy on human fresh cadavers... Turkish Neurosurgery, 30(4), 577-582., Doi: 10.5137/1019-5149.JTN.29021- 20.1 (Quarter Quarters=Q4)

CIRAK MUSA, GÜÇLÜ DOĞAN GÜÇLÜHAN, AKAR EMRE, KAZANCI Mehmet Hanifi, TURAL DENİZ

(2020). Retrospective analysis of survival in patients with brain metastases from

Head of Neurooncology Clinic of Ichilov

Certificates

1. The Course of Functional and Stereotactic Neurosurgery, 1990, Oulu, Finland.

2. European Course participation that holds by EANS for 5 years cycle (Amsterdam/1988, Rostock/1989, Çeşme/1994, Klagenfurt/1995, Aalborg/1996).

3. "Primary Examination" for European Board was passed in Klagenfurt,1995, Austria.

4."Advanced Training on Functional Disorders with Leksell Gamma Knife", 2004, Marseille, France.

5. "Advanced Training on Vestibular Schwannomas and Skull Base Surgery wiyh Leksell Gamma Knife", 2004, Marseille, France.

6. The certificate for "DISC Nucleoplasty in Cervical and Lumbar Disc Diseases", 2004, Freiburg, Germany.

7. "Neuropathfinder" Train - the - Trainer Meeting, 2009, Wien, Austria.

8. " Neuropathfinder" Train - the - Trainer Meeting, 2011, Athens, Greece.

9. The certificate for "Full- Endoscopic Spine Surgery", 2011, Herne, Germany.

Prof. Zvi Ram is a top neurosurgeon and head of the European Association of Neurosurgical Societies (EANS). He specializes in disorders of the brain and spinal cord, such as aneurysms, brain tumors, and Parkinson's Disease. He has received numerous awards for his innovative approach to neurology treatments and research, and is an expert in neurosurgical operations with brain mapping and deep brain stimulation.

Education and Expertise

GATA Military Medical Faculty

GATA Haydarpaşa Training Hospital Neurosurgery Clinic (Specialization)

Beykent University Hospital and Health Institutions Management (Master's)

Experience

GATA Military Medical Faculty Trainee Doctor (6 months)

Samsun Sahara Medical School Comm. (3 months)

Naval Command War Squadron TCG Diligence Medical Officer (2 years)

Dz.K.K. Submarine Battery Factory Infirmary Doctor (3 months)

Naval Forces Command Infirmary Doctor (3 months)

GATA Haydarpaşa Training Hospital Chief Assistant (12 years)

Kasımpaşa Marine Hospital Neurosurgery Clinic Chief (5 years)

Bahçelievler Medical Park Hospital Neurosurgery Specialist (11 years)

Altınbaş University Faculty of Medicine Neurosurgery Lecturer. Member (4 years)

Altınbaş University Faculty of Medicine Head of Neurosurgery Department. (3 years)

Basic and Advanced Cardiac life support courses (BASIC)

Basic and Advanced Cardiac life support courses (ADVANCED)

GATA Military Medical Faculty. Microsurgery Training Course

Istanbul Vatan Hospital Hand surgery microsurgery course

Neuroanatomy course

Spine Surgery course

Professional Memberships

Turkish Neurosurgery Association

Spine Society of Europe

Turkish Spinal and Peripheral Nerve Surgery Group

Dr Önul is FROM THE BEST DOCTORS in the field of Endoscopic skull base surgery and pituitary surgery Brain tumor surgery (Neuro Oncological surgery)


I was born in Artvin in 1977. He became a doctor from KTU Faculty of Medicine in 2001, and Bakırköy Prof. Dr. I became a Neurosurgery Specialist by getting the title of specialist from Mazhar Osman Mental Health and Neurological Diseases Training and Research Hospital. Again, in the same hospital, I was entitled to the title of associate professor in 2016. I continue to work at Başakşehir Çam and Sakura City Hospital, where I voluntarily joined with the task of establishing the Neurosurgery Clinic with my teammates. I am married and have 2 children. I love painting. I am very interested in children's literature. I have 10 printed children's tales

Professor Shlomi Constantini is a highly-trained neurosurgeon in Israel with expertise in general and pediatric neurosurgery, microsurgical operations, reconstructive interventions, and brain and spine tumor treatments. He has received several awards and is a member of multiple professional organizations.

Dr. Margalit Navo is a highly experienced neurosurgeon who heads the Neurosurgery Department at Ichilov (Sourasky) Medical Center. He specializes in the minimally invasive endoscopic removal of skull tumors in both adults and children and has performed over 170 successful surgeries for meningioma and skull base tumors. He is a member of the Israel Neurosurgical Society, North American Skull Base Society, and Israel Medicine Association.

Specializations

Brain Tumors

Aneurysm Surgery

Pituitary Surgery

Spine Surgery

Waist neck and back hernias

Spine Tumors

Spinal Fractures

Peripheral Nerve Surgery

Dr. Türe developed a step-wise teaching method for utilizing the microscope and suction tube. He then presented this technique to the neurosurgical community by teaching neurosurgeons and visiting laboratories internationally. He was also President of the WFNS 16th World Congress of Neurosurgery in Istanbul, Turkey in 2017.

EDUCATION:

• Turhan and Mediha Tansel Primary School (1979–1984)
• Kültür College (1984–1988)
• Semiha Şakir High School (1988–1991)
• Marmara University Faculty of Medicine (1991–1997)
• Marmara University Faculty of Medicine, Neurosurgery Department, Specialist Training (1997–2002)
• Title of Associate Professor in Neurosurgery (May 31, 2021)

ADDITIONAL TRAINING:

• "Visiting Physician," University of Southern California, Department of Neurosurgery (1998)
• "Microsurgery Training," GATA (Gülhane Military Medical Academy), Ankara Education and Research Hospital (2003)

PROFESSIONAL EXPERIENCE:

• Gülhane Military Medical Academy Haydarpaşa Training and Research Hospital (2002–2003)
• Dr. Lütfi Kırdar Kartal Training and Research Hospital (2003–2005)
• Private Avicenna Ataşehir Hospital (2005–2012)
• Private 29 Mayıs Hospital (2012–2013)
• Maltepe State Hospital (2013–2018)
• Kartal Dr. Lütfi Kırdar City Hospital (2018–2020)
• Private Academic Hospital (2020–2022)
• Hisar Intercontinental Hospital (2022–2024)
• Private Medipol Acıbadem Regional Hospital (2024–Present)

ADMINISTRATIVE AND ACADEMIC ROLES:

• Board Member, Neurosurgical Society (2006–2009)
• Head of the Emergency Department, Maltepe State Hospital (2014–2016)
• Deputy Chief Physician, Private Academic Hospital (2020–2021)
• Advisory Board Member, Beykent University Faculty of Medicine (2018–2024)
• Faculty Member, Galata University Faculty of Health Sciences (2022–2024)
• Director, Continuous Education Center, Galata University (2022–2024)

Specialization: Neurospinal Cord and Nerve Surgery

Foreign Language : English

Date of Birth: 03.02.1974

Education :

Gazi University Faculty of Medicine (1991-1997)
Fırat University Neurosurgery Specialization (1999-2004)

Experience:

Private Adatip Hospital (2004-2013)
Private Cihan Hospital (2013-2015)
Private Adatip Hospital (2015-...)

Memberships:

Sakarya Medical Chamber
Turkish Neurosurgery Association

Experience

2019 – 2019

• University of Insubria, Varese, Italy, 

Insubria University Faculty of Medicine

2015

• MERSİN UNIVERSITY/FACULTY OF MEDICINE, DOCTOR, LECTURER

2013 – 2015

• ANKARA PRIVATE ACIBADEM HOSPITAL

2010 – 2012

• DIYARBAKIR TRAINING AND RESEARCH HOSPITAL,

2002 – 2003

• AYDIN 1ST PRIVATE TRAINING BATTALION
•  

Education

2010

• ANKARA UNIVERSITY FACULTY OF MEDICINE, BRAIN AND SURGERY SPECIALIST

1992

• GAZI UNIVERSITY, FACULTY OF MEDICINE

Trustworthy, attentive, successful neurosurgeon with over 34 years of experience, high rate of success and exceptional surgical skills, providing quality neurological service for patients, successfully treating over thousands of patients suffering from many severe, complex conditions of the brain, spine and the nerves. 

Experienced in performing treatment modalities like micro neurosurgery, endoscopic skull base surgery, endoscopic third ventriculostomy, minimally invasive spine surgery and percutaneous spine surgery. Keen on performing clinical research and attending national and international medical conferences to stay abreast of new technologies in the field. Compassionate and detail-oriented with excellent communication skills. Expertise in healthcare, education and program management. Adept at developing and implementing forward-thinking strategies to enhance patient outcomes and collective knowledge in the field. Desiring to bring skills and success. Focused on working closely with other medical professionals and following up with patients. Well-versed at emergency procedures and fast and accurate sanitation.

Work History

2020-01 – Current - Asst. Prof. Neurosurgeon

Istanbul Medipol University, Health Care Practice and Research Center Pendik Hospital

• He successfully treated and followed patients with cerebral hemorrhage, brain and spinal cord tumors, and patients with hydrocephalus.

• He performed transnasal pituitary surgeries with success.

• Also, many cervical lumbar and thoracic disc patients were successfully treated, and disc prosthesis were applied to some of them.

• He re-operated a degenerative spine patient who had been operated on before at another center and the patient regained his health.

• He also successfully treated patients with premature neonatal intracerebral hemorrhage.

2019-08 – 2020-01 - Neurosurgeon

Freelancer, Istanbul, Turkey

• Operated on patients' brains, spines and peripheral nerves to correct deformities, repair injuries, prevent and treat diseases and improve patients' motor functions. Performed successful operations for complex, advanced and complicated disease of the brain and spine some of which were operated unsuccessfully at other medical centers by different neurosurgeons.

• Offered advanced knowledge, leadership abilities and technical assistance with complex surgical cases.

• Maintained admitting privileges at local hospitals and provided quality follow-up care.

• Educated patients on recovery methods and times.

• Designed treatment plans for patients.

• Thoroughly assessed patients to identify medical condition and level of surgical risk.

• Founded a spinal surgery group with orthopedic surgeons and treated very advanced and severe vertebra deformities, spine abnormalities, scoliosis.

2018-12 - 2019-08 - Neurosurgeon

Alkafeel Super Speciality Hospital, Karbala, Iraq

• Conducted up to 5 operations per month to correct deformities in neurological and spinal systems, repair traumas, and treat diseases of different areas. Performed successful operations (success rate 100 percent : 90-95) for severe, complex and advanced diseases of the brain, spine and nerves in adults and children. (Cerebral intrinsic and extrinsic tumor surgery, posterior fossa surgery, spontaneous and traumatic intracranial hematomas, Interhemispheric 3th ventricle and lateral ventricle surgery, pontocerebellar angle tumor surgery, spinal instrumentation and fusion surgery, microdiscectomy cervical, thoracic, lumbar, pediatric cranial and spine anomaly surgery). Followed the patients postoperatively.

• Educated patients on recovery methods and times.

• Thoroughly assessed patients to identify medical condition and level of surgical risk.

• Performed emergency surgeries.

• Examined 900 patients in total in the outpatient clinic and gave medical treatments to them when necessary.

2015-10 - 2018-11 - Neurosurgeon

Medistate Kavacık Hospital, Istanbul, Turkey

• Operated on patients' brains, spines and peripheral nerves to correct deformities, repair injuries, prevent and treat different advanced, complex severe diseases and improve patients' motor functions.

• Conducted up to operations per month to correct deformities in neurological and spinal systems, repair traumas, restore partial or full functionality and prevent and treat diseases of different areas. 

• Performed successful operations (success rate percent : 95) for severe, complex and advanced diseases of the brain , spine and nerves in adults and children.(Brain tumor, arachnoid cyst, intracerebral hematoma, spinal stenosis, hydrocephalus, myelomeningocele).Followed the patients postoperatively. 

• Educated patients on recovery methods and times Thoroughly assessed patients to identify medical condition and level of surgical risk.

• Performed emergency surgeries (intracerebral hematoma, intracerebral abscess).

• Examined 850 patients in total in the outpatient clinic and gave medical treatment to them when necessary.

1994-03 - 2015-09 - Neurosurgeon

Ankara Training and Research Hospital, Ankara, Turkey

• Supervised trainees, medical students, residents and fellows to help each achieve proficiency in field.

• Conducted up to 20 operations per month to correct deformities in neurological and spinal systems, repair traumas, restore partial or full functionality and prevent and treat diseases of different areas. Performed successful operations (success rate: %90) for severe, complex and advanced diseases of the brain, spine and nerves in adults and children. (Skull base surgery, extended trans base approach, orbit zygomatic approach, presigmoid approach, orbital approaches, transcranial and lateral orbitotomy, Endoscopic transsphenoidal pituitary surgery, CSF leakage surgery, endoscopic, microscopic and transsphenoidal, transcranial. Endoscopic third ventriculostomy and surgery of multiloculated hydrocephalus and pediatric neurosurgery. Cerebral intrinsic and extrinsic tumor surgery, posterior fossa surgery. Brain aneurysm, AVM and cavernoma surgery.

• Spontaneous and traumatic intracranial hematomas. Hemifacial spasm and trigeminal neuralgia surgery (microsurgical decompression) Interhemispheric 3th ventricle and lateral ventricle surgery. Pineal area surgery. Pontocerebellar angle tumor surgery.

• Foreman magnum tumors surgery. Surgery of hydrocephaly, Syringomyelia and craniovertebral animalia).Followed the patients postoperatively.

• Educated patients on recovery methods and times Thoroughly assessed patients to identify medical condition and level of surgical risk.

• Performed emergency surgeries (Epidural, subdural and intracerebral hematoma, vertebra fracture).

• Examined 500-700 patients per day in the outpatient clinic and gave medical treatment to them when necessary. Examined patients in the emergency service.

• Designed treatment plans for patients.

• Offered advanced knowledge, leadership abilities and technical assistance with complex surgical cases.

• Led and oversaw 15 medical personnel in operating room setting to perform surgeries.

• Led and oversaw medical personnel in operating room setting to perform surgeries.

Education

1982-09 - 1988-08

M.D.: Medicine And (Pre-Medicine)

Ankara University Medical School - Ankara

General Medicine Training for 6 years. Graduated with a high GPA.

1988-11 - 1994-05

Specialist Neurosurgery: Neuroscience

University of Health Sciences - Ankara

6 years of neurosurgery training.

• My thesis was on brain abscess and their clinical and laboratory evaluations

1995-05 - 1995-07

Neuroscience

The Institute of Neurological Sciences and Psychiatry.

Ankara

I attended the course for microsurgery at University of Hacettepe Institute of Neurological Sciences and Psychiatry.

1998-04 - 2019-05

Observer Doctor: Neuroscience

Department of Neurosurgery, MSU - Ann Arbour, 

Michigan USA

2012-05 - 2012-05

Neuro endoscopy: Neuroscience

Ghent University - Ghent, Belgium

International endoscopic neurosurgery workshop, 

Ghent, Belgium

I attended the workshop for endoscopic skull base operations the and Neuro endoscopic third ventriculostomy at University of Ghent Hospital

Skills

Micro neurosurgery - Excellent

Neuro endoscopy - Excellent

Cranial base endoscopy - Excellent

Minimal invasive surgery - Excellent

Percutaneous spinal surgery - Excellent

Neuronavigation – Excellent

Certifications

1995-04 Microsurgery

2012-05 Endoscopy

Languages

Turkish - Native

English - Advanced

Arabic - Novice

Affiliations

Turkish Neurosurgical Society

Turkish Medical Association

Accomplishments

• Trained team of staff nurses in medical office procedures to ensure consistent quality of care.

• Published 17 articles in national and international reviews and presented papers in medical congresses.

Interests and operations I perform

Vascular diseases of brain

Endoscopic hypophysis surgery

Tumors of brain, spine and medulla spinalis surgery

Endoscopic brain ventricle surgery

Endoscopic third ventriculostomy 

Traumas of brain and spine

Cervical, thoracic and lumbar disc hernias and narrow 

canal disease surgery

Spine instrumentation and fusion surgery

Baclofen pump and neurostimulators insertions

Hydrocephalus surgery

Congenital diseases of the brain and spine (pediatric 

neurosurgery)

Peripheral nerve surgery

Dr. Andrew Kaye is a leading neurosurgeon with 47 years of experience, specializing in surgical treatment of brain tumors, skull base surgery, removal of pituitary tumors, and surgery on the blood vessels of the brain. He is an award-winning doctor who graduated from the University of Melbourne, has held various positions of leadership, and is a member of several neurosurgical societies.