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2.
Phys Rev Lett ; 132(7): 076902, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38427888

ABSTRACT

We study experimentally and theoretically the hybridization among intralayer and interlayer moiré excitons in a MoSe_{2}/WS_{2} heterostructure with antiparallel alignment. Using a dual-gate device and cryogenic white light reflectance and narrow-band laser modulation spectroscopy, we subject the moiré excitons in the MoSe_{2}/WS_{2} heterostack to a perpendicular electric field, monitor the field-induced dispersion and hybridization of intralayer and interlayer moiré exciton states, and induce a crossover from type I to type II band alignment. Moreover, we employ perpendicular magnetic fields to map out the dependence of the corresponding exciton Landé g factors on the electric field. Finally, we develop an effective theoretical model combining resonant and nonresonant contributions to moiré potentials to explain the observed phenomenology, and highlight the relevance of interlayer coupling for structures with close energetic band alignment as in MoSe_{2}/WS_{2}.

3.
Nano Lett ; 23(10): 4160-4166, 2023 May 24.
Article in English | MEDLINE | ID: mdl-37141148

ABSTRACT

Vertical van der Waals heterostructures of semiconducting transition metal dichalcogenides realize moiré systems with rich correlated electron phases and moiré exciton phenomena. For material combinations with small lattice mismatch and twist angles as in MoSe2-WSe2, however, lattice reconstruction eliminates the canonical moiré pattern and instead gives rise to arrays of periodically reconstructed nanoscale domains and mesoscopically extended areas of one atomic registry. Here, we elucidate the role of atomic reconstruction in MoSe2-WSe2 heterostructures synthesized by chemical vapor deposition. With complementary imaging down to the atomic scale, simulations, and optical spectroscopy methods, we identify the coexistence of moiré-type cores and extended moiré-free regions in heterostacks with parallel and antiparallel alignment. Our work highlights the potential of chemical vapor deposition for applications requiring laterally extended heterosystems of one atomic registry or exciton-confining heterostack arrays.

4.
Dis Colon Rectum ; 66(5): 681-690, 2023 05 01.
Article in English | MEDLINE | ID: mdl-36856669

ABSTRACT

BACKGROUND: Consolidation chemotherapy strategies have demonstrated improved pathological complete response and tumor downstaging rates for patients diagnosed with rectal cancer. OBJECTIVE: This study aimed to compare perioperative outcomes and pathological complete response rates among different neoadjuvant treatment strategies in patients undergoing total mesorectal excision for locally advanced rectal cancer. DESIGN: Propensity score case-matched study. SETTING: High-volume tertiary care centers. PATIENTS: Consecutive patients undergoing curative total mesorectal excision between January 2014 and June 2021 were queried. INTERVENTIONS: Patients were divided into 3 groups: long-course chemoradiation therapy with (N = 128) or without (N = 164) consolidation chemotherapy or short-course radiotherapy (N = 53) followed by consolidation chemotherapy. MAIN OUTCOME MEASURES: Demographics, preoperative tumor characteristics, histopathologic outcomes, and postoperative complication rates were reviewed and compared. Propensity score match analysis was conducted. RESULTS: A total of 345 patients (mean age: 58 ± 12 years; female: 36%) met the study inclusion criteria. Time interval from neoadjuvant treatment until surgery was longer for patients receiving consolidation chemotherapy ( p < 0.001). Pathological complete response rates were comparable among patients receiving long-course chemoradiation therapy (20.3%) and short-course radiotherapy with consolidation chemotherapy (20.8%) compared to long-course chemoradiation therapy alone (14.6%) ( p = 0.36). After the propensity score case-matched analysis, 48 patients in the long-course chemoradiation therapy with consolidation chemotherapy group were matched to 48 patients in the short-course radiotherapy with consolidation chemotherapy group. Groups were comparable with respect to age, sex, clinical stage, tumor location, type of surgical approach, and technique. Pathological complete response rate was comparable between the groups (20.8% and 18.8%, p = 0.99). LIMITATIONS: Study was limited by its retrospective nature. CONCLUSIONS: Among recent neoadjuvant treatment modalities, pathological complete response rates, and short-term clinical outcomes were comparable. Short-course radiotherapy with consolidation chemotherapy is safe and effective as long-course chemoradiation therapy as in a short-term period. See Video Abstract at http://links.lww.com/DCR/C174 . LA RADIOTERAPIA DE CORTA DURACIN SEGUIDA DE QUIMIOTERAPIA DE CONSOLIDACIN ES SEGURA Y EFICAZ EN EL CNCER DE RECTO LOCALMENTE AVANZADO RESULTADOS COMPARATIVOS A CORTO PLAZO DEL ESTUDIO MULTICNTRICO DE CASOS EMPAREJADOS POR PUNTAJE DE PROPENSION: ANTECEDENTES: Las estrategias de quimioterapia de consolidación han demostrado una mejor respuesta patológica completa y tasas de reducción del estadio del tumor para pacientes diagnosticados con cáncer de recto.OBJETIVO: Comparar los resultados perioperatorios y las tasas de respuesta patológica completa entre diferentes estrategias de tratamiento neoadyuvante en pacientes sometidos a escisión mesorrectal total por cáncer de recto localmente avanzado.DISEÑO: Estudio de casos emparejados por puntaje de propensión.ENTORNO CLINICO: Centros de atención terciaria de alto volumen.PACIENTES: Pacientes consecutivos sometidos a escisión mesorrectal total curativa por cáncer de recto localmente avanzado entre enero de 2014 y junio de 2021.INTERVENCIONES: Los pacientes se dividieron en tres grupos según la modalidad de tratamiento neoadyuvante: quimiorradioterapia de ciclo largo con (N = 128) o sin (N = 164) quimioterapia de consolidación o radioterapia de ciclo corto (N = 53) seguida de quimioterapia de consolidación.PRINCIPALES MEDIDAS DE RESULTADO: El punto final primario fue la respuesta patológica completa. Se revisaron y compararon los datos demográficos, las características preoperatorias del tumor, los resultados histopatológicos y las tasas de complicaciones posoperatorias entre los grupos de estudio. Se realizó un análisis de casos emparejados por puntaje de propensión.RESULTADOS: Un total de 345 pacientes (edad media de 58 ± 12 años y mujeres: 36%) cumplieron los criterios de inclusión del estudio. El intervalo de tiempo desde el tratamiento neoadyuvante hasta la cirugía fue mayor para los pacientes que recibieron quimioterapia de consolidación ( p < 0,001). Las tasas de respuesta patológica completa fueron comparables entre los pacientes que recibieron quimiorradioterapia de larga duración con quimioterapia de consolidación (20,3 %) y radioterapia de corta duración con quimioterapia de consolidación (20,8%) en comparación con la quimiorradiación de larga duración sola (14,6%) ( p = 0,36). Después del análisis de casos emparejados por puntaje de propensión, 48 pacientes en el grupo de quimiorradioterapia de ciclo largo con quimioterapia de consolidación se emparejaron con 48 pacientes en el grupo de radioterapia de ciclo corto con quimioterapia de consolidación. Los grupos fueron comparables con respecto a la edad, sexo, estadio clínico, ubicación del tumor, tipo de abordaje quirúrgico y la técnica. La tasa de respuesta patológica completa fue comparable entre los grupos (20,8% y 18,8%, p = 0,99). La morbilidad postoperatoria a los 30 días y las tasas de fuga anastomótica fueron similares.LIMITACIONES: El estudio estuvo limitado por su naturaleza retrospectiva.CONCLUSIONES: Entre las modalidades de tratamiento neoadyuvante recientes, las tasas de respuesta patológica completa y los resultados clínicos a corto plazo fueron comparables. La radioterapia de corta duración con quimioterapia de consolidación es segura y eficaz como terapia de quimiorradioterapia de larga duración en un período corto. Consulte Video Resumen en http://links.lww.com/DCR/C174 . (Traducción-Dr. Fidel Ruiz Healy ).


Subject(s)
Consolidation Chemotherapy , Rectal Neoplasms , Humans , Female , Middle Aged , Aged , Retrospective Studies , Propensity Score , Rectal Neoplasms/surgery , Postoperative Complications/drug therapy
5.
Nat Nanotechnol ; 18(6): 572-579, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36973398

ABSTRACT

Moiré effects in vertical stacks of two-dimensional crystals give rise to new quantum materials with rich transport and optical phenomena that originate from modulations of atomic registries within moiré supercells. Due to finite elasticity, however, the superlattices can transform from moiré-type to periodically reconstructed patterns. Here we expand the notion of such nanoscale lattice reconstruction to the mesoscopic scale of laterally extended samples and demonstrate rich consequences in optical studies of excitons in MoSe2-WSe2 heterostructures with parallel and antiparallel alignments. Our results provide a unified perspective on moiré excitons in near-commensurate semiconductor heterostructures with small twist angles by identifying domains with exciton properties of distinct effective dimensionality, and establish mesoscopic reconstruction as a compelling feature of real samples and devices with inherent finite size effects and disorder. Generalized to stacks of other two-dimensional materials, this notion of mesoscale domain formation with emergent topological defects and percolation networks will instructively expand the understanding of fundamental electronic, optical and magnetic properties of van der Waals heterostructures.


Subject(s)
Electronics , Semiconductors
6.
J Laparoendosc Adv Surg Tech A ; 31(11): 1247-1253, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33416432

ABSTRACT

Background: Obesity is one of the contributing factors to technical difficulties in minimally invasive colorectal surgery. However, there are no data regarding the outcomes for obese patients undergoing robotic complete mesocolic excision (CME) for colon cancer. In this study, we aimed to investigate whether robotic CME in obese patients can be performed with similar morbidity and pathological results compared with nonobese patients. Methods: Patients who underwent robotic CME between 2014 and 2019 were classified into obese and nonobese groups. Obesity was defined as body mass index ≥30 kg/m2. Demographic data, perioperative outcomes and pathological results were compared between the groups. Results: There were 42 and 105 patients in the obese and nonobese group, respectively. The groups were comparable regarding preoperative characteristics. There were no significant differences with respect to operative times (244 ± 64 versus 304 ± 75 minutes, P = .29), blood loss (median, 50 versus 80 mL, P = .20), intraoperative complications (0% versus 3.8%, P > .99), and conversions (0% versus 1.9%, P > .99). No differences were detected in length of hospital stay (6 ± 1 versus 6 ± 2 days, P = .73), anastomotic leak (2.4% versus 1.9%, P > .99), septic complications, reoperations (2.4% versus 3.8%), and readmissions (2.4% versus 2.9%) (P > .05). The mean number of harvested lymph nodes (33 ± 11 versus 34 ± 13, P = .79), resection margin status, and mesocolic fascia grading were similar. Conclusion: Robotic CME in obese patients can be performed with a similar morbidity and pathological profile compared with nonobese patients. The Clinical Trial Registration number is not applicable for this study.


Subject(s)
Colonic Neoplasms , Obesity , Robotic Surgical Procedures , Colectomy , Colonic Neoplasms/surgery , Humans , Obesity/complications , Robotic Surgical Procedures/adverse effects
7.
Int J Pharm ; 592: 119999, 2021 Jan 05.
Article in English | MEDLINE | ID: mdl-33190790

ABSTRACT

The infection of bone and bone marrow is called osteomyelitis. Treatment is difficult since antibiotics can not reach with enough concentration to the infected area. For the first time in this study, we have developed gentamicin-loaded magnetic gelatin nanoparticles (GMGNPs) for nanocarrier-mediated and magnetically targeted osteomyelitis therapy. Gelatin, genipin, and magnetite were used for preparation of that novel carrier system due to their biodegradable and biocompatible properties. Cross-linking degree of gelatin nanoparticles, concentration of magnetite nanoparticles, and adsorbed drug amount were optimized. Furthermore, nanoparticles were characterized and the drug release profile was determined. The osteomyelitis model was constituted in the proximal tibia of rats. The therapeutic potential of GMGNPs on rats was monitored via X-Ray radiography and hematological and histopathological analyses were performed. According to the results, 110.3 ± 8.2 µg gentamicin/mg GMGNPs were used, hydrodynamic size was measured as 253.7 ± 11.8 nm, and GMGNPs have controlled drug release profile. Based on in vivo and ex vivo studies, after six doses of GMGNPs treatment, abscess began to heal and the integrity of periost and bone began to reconstruct. In conclusion, it can be suggested that GMGNPs could provide efficient therapy for osteomyelitis.


Subject(s)
Magnetite Nanoparticles , Nanoparticles , Osteomyelitis , Animals , Anti-Bacterial Agents/therapeutic use , Drug Carriers/therapeutic use , Gelatin , Gentamicins , Osteomyelitis/drug therapy , Rats
8.
Int J Med Robot ; 16(6): 1-5, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33289228

ABSTRACT

BACKGROUND: The purpose of this study was to assess the learning curve (LC) for inguinal hernia repair with robotic transabdominal preperitoneal (R-TAPP) approach. METHODS: Between April 2016 and October 2019, patients who underwent R-TAPP were retrieved. Patient demographics, operative variables and postoperative outcomes were assessed. The moving average method and cumulative sum of operation times (OT) were used to evaluate the LC. The surgeon (BB) in this study had completed his laparoscopic (Lap) TAPP experience. RESULTS: There were 50 (two females) consecutive patients (mean age was 51.7 ± 16.9 years). The first phase (learning phase) included initial 35 operations. The second phase included the next 15 operations. It was observed that, with increasing experience, a statistically significant shortening in the average OT by about 25 min was achieved (p = 0.041). CONCLUSION: The LC phase for R-TAPP, for surgeon with previous experience in Lap TAPP, seems to be very quick without compromising the operative morbidity.


Subject(s)
Hernia, Inguinal , Laparoscopy , Robotic Surgical Procedures , Adult , Aged , Female , Hernia, Inguinal/surgery , Herniorrhaphy , Humans , Learning Curve , Male , Middle Aged , Retrospective Studies
9.
Int J Med Robot ; 16(6): 1-10, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32920968

ABSTRACT

BACKGROUND: This study aimed to compare short- and long-term outcomes after robotic versus laparoscopic approach in patients undergoing curative surgery for rectal cancer. METHODS: Patients undergoing elective robotic and laparoscopic resection for rectal cancer were included. Perioperative clinical characteristics, postoperative short- and long-term outcomes were compared between groups. RESULTS: There were 72 and 44 patients in robotic (RG) and laparoscopic (LG) groups respectively. No differences were detected regarding patients' demographics, histopathologic outcomes, conversion rates and 30-day overall postoperative complication rates. Operative time was longer in the RG (341 ± 111.7 vs. 263 ± 97.5 min, p = 0.001) and length of stay was longer in the LG (4.4 ± 1.9 vs. 6.4 ± 2.9 days, p = 0.001). The 5-year overall and disease-free survival rates were similar (97.1% and 94.9%, p = 0.78; 86.2% and 82.7%, p = 0.72) between the groups. CONCLUSION: This study showed both short and long-term outcomes of a limited number of included patients between the robotic and laparoscopic surgery were similar. However, future studies and randomized trials are necessary to establish these findings.


Subject(s)
Laparoscopy , Rectal Neoplasms , Robotic Surgical Procedures , Robotics , Humans , Operative Time , Postoperative Complications , Rectal Neoplasms/surgery , Retrospective Studies , Treatment Outcome
10.
Surg Laparosc Endosc Percutan Tech ; 30(6): 511-517, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32694403

ABSTRACT

BACKGROUND: This study primarily aimed to assess the impact of prolonged neoadjuvant treatment-surgery interval (PNSI) on histopathologic and postoperative outcomes. Impacts of the mode of neoadjuvant treatment (NT) and surgery on the outcomes were also evaluated in the same patient population. PATIENTS AND METHODS: Between February 2011 and December 2017, patients who underwent NT and total mesorectal excision for locally advanced rectal cancer were included. PNSI was defined as >4 and >8 weeks after short-course and long-course NT modalities, respectively. RESULTS: A total of 44 (27%) patients received short-course NT (standard interval: n=28; PNSI: n=16) and 122 (73%) patients received long-course NT (standard interval: n=39; PNSI: n=83). Postoperative morbidity was similar between the standard interval and PNSI in patients undergoing short-course [n=3 (11%) vs. n=3 (19%), P=0.455] and long-course [n=6 (15%) vs. n=16 (19%), P=0.602] NT. PNSI was associated with increased complete pathologic response in patients receiving short-course NT [0 vs. n=5 (31%), P=0.002]. Compared with short-course NT, long-course NT was superior in terms of tumor response based on the Mandard [Mandard 1 to 2: n=6 (21%) vs. 6 (38%), P=0.012] and the College of American Pathologists (CAP) [CAP 0 to 1: n=13 (46%) vs. n=8 (50%), P=0.009] scores. Postoperative morbidity was similar after open, laparoscopic, and robotic total mesorectal excision [n=1 (14.2%) vs. n=21 (21%) vs. n=6 (12.5%), P=0.455] irrespective of the interval time to surgery and the type of NT. CONCLUSIONS: PNSI can be considered in patients undergoing short-course NT due to its potential oncological benefits. The mode of surgery performed at tertiary centers has no impact on postoperative morbidity after both NT modalities.


Subject(s)
Laparoscopy , Rectal Neoplasms , Humans , Neoadjuvant Therapy , Rectal Neoplasms/surgery , Rectum/surgery , Retrospective Studies , Treatment Outcome
11.
Int J Med Robot ; 16(4): e2111, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32303112

ABSTRACT

BACKGROUND: In this study, we aimed to compare short- and long-term outcomes between laparoscopic totally extraperitoneal (L-TEP) and robotic transabdominal preperitoneal (R-TAPP) inguinal hernia repair. METHODS: Patients were classified into two groups: L-TEP and R-TAPP. The groups were case-matched in a 1:1 ratio based on age, gender, and body mass index (BMI). RESULTS: Out of 86 patients, 43 patients were matched in each group based on the study criteria. Demographics were comparable between the groups. Operative time was significantly longer for the R-TAPP compared to L-TEP (129.1 ± 47.2 min vs 92.5 ± 28.3 min; P < .001). VAS scores at 24 hours after surgery were significantly higher in the L-TEP compared to R-TAPP (36.8 ± 20.1 vs 20.3 ± 18.7; P < .001). Total hospital costs were 4778$ for R-TAPP and 3852$ for L-TEP. CONCLUSION: The current study demonstrates similar long-term postoperative outcomes and recurrence rates between robotic and laparoscopic inguinal hernia repair in a case-matched fashion.


Subject(s)
Hernia, Inguinal , Laparoscopy , Robotic Surgical Procedures , Hernia, Inguinal/surgery , Herniorrhaphy , Humans , Operative Time , Surgical Mesh , Treatment Outcome
12.
Langenbecks Arch Surg ; 405(1): 63-69, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32006086

ABSTRACT

PURPOSE: Live surgical demonstrations are considered an effective educational tool providing a chance for trainees to observe a real-time decision-making process of expert surgeons. No data exists evaluating the impact of live surgical demonstrations on the outcomes of minimally invasive colorectal surgery. This study evaluates perioperative and short-term postoperative outcomes in patients undergoing minimally invasive colorectal surgery in the setting of live surgical demonstrations. METHODS: Patients undergoing minimally invasive colorectal surgery which was performed as live surgical demonstrations (the study group) performed between 2006 and 2018 were reviewed. These patients were case-matched with those undergoing operations in routine practice (the control group). The study and control group were compared for intraoperative and short-term postoperative outcomes. RESULTS: Thirty-nine live surgery cases in the study group were case-matched with its thirty-nine counterparts as the control group. Operating time was longer (200 vs 165 min; p = 0.002) and estimated intraoperative blood loss was higher in the study group (100 vs 55 ml; p = 0.008). Patients in the study group stayed longer in the hospital (6 vs 5 days; p = 0.001). While conversion (n = 4 vs n = 1, p = 0.358) and intraoperative complications (n = 6 vs n = 2, p = 0.2) were more frequent in the study group, these outcomes did not reach statistical significance. Overall complications were higher in the study group (n = 22 vs n = 9, p = 0.003). One patient underwent a reoperation due to postoperative bleeding, and one mortality occurred in the live surgery group. CONCLUSIONS: Live surgical demonstrations in minimally invasive colorectal surgery seem to be associated with increased risk of operative morbidity.


Subject(s)
Colorectal Surgery/education , Gastrointestinal Diseases/surgery , Minimally Invasive Surgical Procedures/education , Adult , Aged , Colorectal Surgery/statistics & numerical data , Female , Humans , Intraoperative Complications/epidemiology , Intraoperative Complications/etiology , Laparoscopy/education , Laparoscopy/statistics & numerical data , Male , Middle Aged , Minimally Invasive Surgical Procedures/statistics & numerical data , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Retrospective Studies , Treatment Outcome
13.
J Wound Ostomy Continence Nurs ; 47(1): 72-74, 2020.
Article in English | MEDLINE | ID: mdl-31929448

ABSTRACT

BACKGROUND: Stoma creation is a common procedure in colorectal surgery. Despite improved surgical techniques, ostomy-related wound complications may prolong the recovery period and impair health-related quality of life. Negative pressure wound therapy (NPWT), autolytic debridement agents, and silver dressings are often used for managing complex wound infection and dehiscence. These applications have the potential to increase patient comfort and accelerate recovery. CASE: We report our experience in a 66 year old female who had a wound dehiscence involving the ostomy after robotic abdominoperineal resection. Her medical history was significant for a rectovaginal fistula which occurred after a low anterior resection for rectal cancer 5 years ago. Interventions for treatment of the dehiscence were use of NPWT, autolytic debriding agent, and silver dressing. CONCLUSION: Combined use of these interventions for dehiscence of an ostomy can minimize patient discomfort and accelerate wound healing.


Subject(s)
Ostomy/adverse effects , Surgical Wound Dehiscence/therapy , Aged , Digestive System Surgical Procedures/adverse effects , Digestive System Surgical Procedures/methods , Female , Humans , Ostomy/methods , Postoperative Complications/therapy , Turkey , Wound Healing
14.
Surg Laparosc Endosc Percutan Tech ; 30(1): 40-44, 2020 Feb.
Article in English | MEDLINE | ID: mdl-30768495

ABSTRACT

In this study, we aimed to present our initial experience on totally robotic total restorative proctocolectomy in ulcerative colitis (UC) patients. Patients undergoing a totally robotic restorative total proctocolectomy with ileal J-pouch anal anastomosis for UC between January 2015 and November 2017 were included. The da Vinci Xi was used for the operations. Patient demographics, perioperative and short-term operative outcomes were evaluated. Ten patients were included. The median operative time was 380 minutes(range, 300 to 480 min). The median blood loss was 65 mL (range, 5 to 400 mL). No conversion to open surgery was needed. The median time to flatus was 1 day (range, 1 to 2) and length of stay was 6 (4 to 12) days. Short-term complications (≤30 d) were superficial wound infection (n=3), anal bleeding (n=1), pouchitis (n=1). No mortality was observed during the study period. Our study, which is the largest series so far, reveals that totally robotic restorative proctocolectomy is a safe and feasible option for the surgical treatment of UC.


Subject(s)
Anal Canal/surgery , Colitis, Ulcerative/surgery , Colonic Pouches , Proctocolectomy, Restorative/methods , Robotic Surgical Procedures/methods , Adolescent , Adult , Anastomosis, Surgical/methods , Female , Follow-Up Studies , Humans , Male , Middle Aged , Operative Time , Prospective Studies , Time Factors , Treatment Outcome , Young Adult
15.
Int J Med Robot ; 16(1): e2068, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31875352

ABSTRACT

BACKGROUND: Introduction of the da Vinci Xi system has facilitated the use of robotics in colorectal surgery. Nevertheless, data on the outcomes of robotic surgery for the treatment of colonic diverticulitis have remained scarce. METHODS: Patient demographics, clinical characteristics, and perioperative outcomes of the patients undergoing totally robotic with the da Vinci Xi system or laparoscopic surgery for left-sided colonic diverticulitis (LCD) were compared. RESULTS: Laparoscopic and robotic groups included 22 and 20 patients, respectively. There were no significant differences between the two groups in terms of patient demographics, clinical characteristics, operative time, and postoperative complications. There were three conversions in the laparoscopy group and no conversion in the robotic group (P = 0.23). Conversion to open surgery was associated with postoperative morbidity (P = 0.02). CONCLUSION: Robotic surgery is an applicable alternative for the treatment of LCD. Robotic approach may potentially lower the risk of operative morbidity by reducing the requirement of conversion.


Subject(s)
Diverticulitis, Colonic/surgery , Laparoscopy/methods , Robotic Surgical Procedures/methods , Adult , Aged , Female , Humans , Laparoscopy/adverse effects , Male , Middle Aged , Operative Time , Postoperative Complications/etiology , Robotic Surgical Procedures/adverse effects
16.
Nano Lett ; 20(1): 284-291, 2020 Jan 08.
Article in English | MEDLINE | ID: mdl-31794217

ABSTRACT

One-dimensional defects in two-dimensional (2D) materials can be particularly damaging because they directly impede the transport of charge, spin, or heat and can introduce a metallic character into otherwise semiconducting systems. Current characterization techniques suffer from low throughput and a destructive nature or limitations in their unambiguous sensitivity at the nanoscale. Here we demonstrate that dark-field second harmonic generation (SHG) microscopy can rapidly, efficiently, and nondestructively probe grain boundaries and edges in monolayer dichalcogenides (i.e., MoSe2, MoS2, and WS2). Dark-field SHG efficiently separates the spatial components of the emitted light and exploits interference effects from crystal domains of different orientations to localize grain boundaries and edges as very bright 1D patterns through a Cerenkov-type SHG emission. The frequency dependence of this emission in MoSe2 monolayers is explained in terms of plasmon-enhanced SHG related to the defect's metallic character. This new technique for nanometer-scale imaging of the grain structure, domain orientation and localized 1D plasmons in 2D different semiconductors, thus enables more rapid progress toward both applications and fundamental materials discoveries.

17.
Sci Rep ; 9(1): 13756, 2019 Sep 24.
Article in English | MEDLINE | ID: mdl-31551486

ABSTRACT

Atomically thin crystals of transition metal dichalcogenides (TMDs) host excitons with strong binding energies and sizable light-matter interactions. Coupled to optical cavities, monolayer TMDs routinely reach the regime of strong light-matter coupling, where excitons and photons admix coherently to form polaritons up to room temperature. Here, we explore the two-dimensional nature of TMD polaritons with scanning-cavity hyperspectral imaging. We record a spatial map of polariton properties of extended WS2 monolayers coupled to a tunable micro cavity in the strong coupling regime, and correlate it with maps of exciton extinction and fluorescence taken from the same flake with the cavity. We find a high level of homogeneity, and show that polariton splitting variations are correlated with intrinsic exciton properties such as oscillator strength and linewidth. Moreover, we observe a deviation from thermal equilibrium in the resonant polariton population, which we ascribe to non-Markovian polariton-phonon coupling. Our measurements reveal a promisingly consistent polariton landscape, and highlight the importance of phonons for future polaritonic devices.

18.
Int J Med Robot ; 15(1): e1962, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30334328

ABSTRACT

BACKGROUND: Limited data exist regarding adoption of evolving robotic technology in surgery. This study evaluated trends and the current condition of robotic platforms in surgical specialties and general surgical subspecialties. METHODS: Between January 2013 and December 2017, all robotic operations performed in Turkey were included. RESULTS: In the study period, 13 760 robotic operations were performed at 32 hospitals. The median numbers of general surgical procedures were 43and eight cases per hospital and per general surgeon, respectively. The high-volume general surgeons performed 1734 (81%) of the cases. Forty-five percent and 55% of the general surgical operations were performed with the Xi and S/Si robots, respectively. CONCLUSION: Use of the Xi platform seems to increase caseload in general surgery operations possibly by facilitating robotic colorectal surgery. Targeting the high-volume centres and surgeons for further training and implantation of upcoming robotic technology can be more effective in terms of increasing case volume and improving outcomes.


Subject(s)
Colorectal Neoplasms/surgery , Colorectal Surgery/instrumentation , Colorectal Surgery/statistics & numerical data , General Surgery/statistics & numerical data , Robotic Surgical Procedures/instrumentation , Robotic Surgical Procedures/statistics & numerical data , Digestive System Surgical Procedures , Humans , Operative Time , Treatment Outcome , Turkey/epidemiology
19.
Surg Laparosc Endosc Percutan Tech ; 29(1): 13-17, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30540638

ABSTRACT

Although high-ligated pedicle of the inferior mesenteric artery is usually kept in the resected specimens, the value of preserving high-ligated pedicle of the inferior mesenteric vein within the resected specimens of the sphincter saving rectal resections for cancer is not well defined. In the current study, patients undergoing open, laparoscopic, and robotic sphincter saving rectal resection for cancer were prospectively included. Lymph node invasion and presence of lymph nodes along the IMV pedicles were analyzed. In total 100 patients were included. There were lymph nodes in 63 patients at the IMV and 71 patients at the IMA pedicles. En-bloc removal of the high-ligated IMV pedicle with the resected specimen significantly increased the number of harvested lymph nodes(P<0.001) regardless of surgical modality (P=0.36). Although it increases the number of harvested lymph nodes with acceptable operative morbidity, no oncological benefits were found related to preservation of high-ligated pedicle of the inferior mesenteric vein within the resected specimen of the rectum.


Subject(s)
Laparoscopy/methods , Mesenteric Veins/surgery , Rectal Neoplasms/surgery , Surgical Procedures, Operative/methods , Anal Canal/surgery , Female , Humans , Ligation/methods , Lymph Node Excision/methods , Lymphatic Metastasis , Male , Mesenteric Artery, Inferior/surgery , Middle Aged , Organ Sparing Treatments/methods , Prospective Studies , Treatment Outcome
20.
Turk J Gastroenterol ; 29(4): 406-410, 2018 07.
Article in English | MEDLINE | ID: mdl-30249554

ABSTRACT

BACKGROUND/AIMS: Most of the patients with Crohn's disease (CD) may require at least one surgical procedure over their lifetime. However, these patients tend to have a high incidence of postoperative complications. The aim of this retrospective study was to investigate the predictive parameters of postoperative complications in CD. MATERIALS AND METHODS: All consecutive patients with CD between March 2001 and March 2016 who underwent bowel resection were included to this study. Postoperative complications were divided as; major complications including anastomotic leakage, ostomy complications, acute mechanical intestinal obstruction and hemorrhage, and minor complications including wound infection. RESULTS: A total of 147 patients (74 females, 73 males) with a mean age of 36±11.9 years met the inclusion criteria. Behaviors of CD were stricturing in 90 (62%), fistulizing in 45 (30%) and inflammatory in 12 (8%) patients. Minimally invasive approach was applied in 35% (n=51) of the patients. Twentysix (17%) patients had early (≤30 days) postoperative surgical complications including anastomotic leak (n=10), intra-abdominal bleeding (n=2), complications related to ostomy (n=2), acute mechanical intestinal obstruction (n=1) and wound infection (n=11). Only fistulizing disease behavior was associated with early postoperative complications (p=0.014). CONCLUSION: This study suggests that postoperative complications are still more common in fistulizing CD. Surgical approach did not affect the complication rate. The decision should be individualized according to the prominent risk factors and surgeons' preference.


Subject(s)
Crohn Disease/surgery , Digestive System Surgical Procedures/adverse effects , Intestinal Fistula/surgery , Intestines/surgery , Postoperative Complications/etiology , Adult , Crohn Disease/complications , Digestive System Surgical Procedures/methods , Female , Humans , Intestinal Fistula/etiology , Male , Middle Aged , Retrospective Studies , Risk Factors , Treatment Outcome
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