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Arterial compliance (AC) plays a crucial role in vascular aging and cardiovascular disease. The ability to continuously estimate aortic AC or its surrogate, pulse pressure (PP), through wearable devices is highly desirable, given its strong association with daily activities. While the single-site photoplethysmography (PPG)-derived arterial stiffness indices show reasonable correlations with AC, they are susceptible to noise interference, limiting their practical use. To overcome this challenge, our study introduces a noise-resistant indicator of AC: Katz’s fractal dimension (KFD) of PPG signals. We showed that KFD integrated the signal complexity arising from compliance changes across a cardiac cycle and vascular structural complexity, thereby decreasing its dependence on individual characteristic points. To assess its capability in measuring AC, we conducted a comprehensive evaluation using both in silico studies with 4374 virtual human data and real-world measurements. In the virtual human studies, KFD demonstrated a strong correlation with AC (r = 0.75), which only experienced a slight decrease to 0.66 at a signal-to-noise ratio of 15dB, surpassing the best PPG-morphology-derived AC measure (r = 0.41) under the same noise condition. In addition, we observed that KFD’s sensitivity to AC varied based on the individual’s hemodynamic status, which may further enhance the accuracy of AC estimations. These in silico findings were supported by real-world measurements encompassing diverse health conditions. In conclusion, our study suggests that PPG-derived KFD has the potential to continuously and reliably monitor arterial compliance, enabling unobtrusive and wearable assessment of cardiovascular health.

An efficient gas-phase production of propylene oxide (PO) with noble metal-free catalysts could modify the industrial output of this valuable compound. We present a novel catalyst based on well-dispersed Ni nanoparticles loaded on a Ti-SiO2 support for the propylene epoxidation reaction using H2/O2 mixtures. XPS, High Resolution Transmission Electron Microscopy (HRTEM), and UV–Vis corroborate both the small size of Ni particles and the excellent dispersion and incorporation of Ti as tetrahedral single site species into the silica framework. The catalytic results under steady-state conditions at low temperature (200 °C) show high PO selectivity (around 85%) with a substantial propylene conversion (over 6%) and excellent H2 efficiency (~37%) using only 0.5 wt% of Ni on Ti-SiO2 (Ti/Si = 0.01 M ratio). In this work, we have also carried out a preliminary DFT study to gain understanding of the characteristics that make this nickel catalyst active and selective for the propene epoxidation reaction.

An efficient gas-phase production of propylene oxide (PO) with noble metal-free catalysts could modify the industrial output of this valuable compound. We present a novel catalyst based on well-dispersed Ni nanoparticles loaded on a Ti-SiO2 support for the propylene epoxidation reaction using H2/O2 mixtures. XPS, High Resolution Transmission Electron Microscopy (HRTEM), and UV–Vis corroborate both the small size of Ni particles and the excellent dispersion and incorporation of Ti as tetrahedral single site species into the silica framework. The catalytic results under steady-state conditions at low temperature (200 °C) show high PO selectivity (around 85%) with a substantial propylene conversion (over 6%) and excellent H2 efficiency (~37%) using only 0.5 wt% of Ni on Ti-SiO2 (Ti/Si = 0.01 M ratio). In this work, we have also carried out a preliminary DFT study to gain understanding of the characteristics that make this nickel catalyst active and selective for the propene epoxidation reaction.

A new subporphyrin was synthesized for use as a molecular sensitizer in electrochemical and dye-sensitized photoelectrochemical water oxidation. A photoelectrochemical cell with a TiO2 electrode modified with the sensitizer and a molecular water oxidation catalyst generated higher photocurrent than reference cells that have electrodes modified with either the photosensitizer or the catalyst under visible light (lambda > 500 nm) illumination. Oxygen evolution was confirmed after photolysis by GC and GC-MS analyses using isotope-labeling experiments. The large molar extinction coefficients of the ring-contracted porphyrin in the visible region enabled kinetic analysis by time-resolved transient absorption spectroscopy, which also supported the photocatalytic activity., QC 20170109

Single-atom cobalt centers on various oxide surfaces (TiO2, MgO, SBA-15, AlPO, and Y-Zeolite) were prepared and evaluated as water oxidation catalysts by photochemical water oxidation experiments. Superior catalytic rates were observed for cobalt sites on basic supporting oxides (TiO2 and MgO) relative to those on acidic oxides (Y-Zeolite, AlPO, and SiO2). Per-atom turnover frequencies of ca. 0.04 s-1 were achieved, giving initial rates 100 times greater than that of a surface atom of a Co3O4 nanoparticle. Contrary to expectations based on theoretical work, no apparent correlation was observed between the catalytic rates and the oxygen atom affinities of the supporting oxides. (Graph Presented).

Single-atom cobalt centers on various oxide surfaces (TiO2, MgO, SBA-15, AlPO, and Y-Zeolite) were prepared and evaluated as water oxidation catalysts by photochemical water oxidation experiments. Superior catalytic rates were observed for cobalt sites on basic supporting oxides (TiO2 and MgO) relative to those on acidic oxides (Y-Zeolite, AlPO, and SiO2). Per-atom turnover frequencies of ca. 0.04 s-1 were achieved, giving initial rates 100 times greater than that of a surface atom of a Co3O4 nanoparticle. Contrary to expectations based on theoretical work, no apparent correlation was observed between the catalytic rates and the oxygen atom affinities of the supporting oxides. (Graph Presented).

Diaphragmatic hernia is a quite uncommon disease, being congenital or posttraumatic. Its diagnosis is frequently accidental. Surgical treatment can be performed through the abdomen as well as through the chest. Laparoscopy and thoracoscopy offer a surgical benefit because of reduced wall trauma and added advantages of minimally invasive surgery. Besides the improved cosmetic result, transumbilical single-incision laparoscopy can add other advantages to minimally invasive surgery like reduced postoperative pain, shorter hospital stay, and improved patient's comfort. The authors describe the technique of transumbilical single-incision laparoscopic suture and mesh reinforcement for a nontraumatic left lateral diaphragmatic hernia, discovered accidentally in a 45-year-old male., SCOPUS: ar.j, info:eu-repo/semantics/published

With the advent of natural orifices translumena endoscopic surgery (NOTES) and single-port/single-incision laparoscopy (SPL/SLS), minimally invasive surgery recently underwent to an impressive evolution, mainly improving the cosmesis and reducing the abdominal wall trauma. A new concept to be less invasive in minimally invasive surgery started to be popular and named reduced port laparoscopic surgery (RPLS). A reduced number of trocars associated to a reduced size of each trocar and instrument chracterizes this new technique. During conventional multiport laparoscopic colorectal surgery, the specimen has to be retrieved, hence an enlargement of the trocar or a new opening of the abdominal wall is necessary. With NOTES, surgeons started to consider the natural orifices to remove the specimen from the abdomen (vagina/rectum), and with SPL/SLS to minimize the abdominal trauma and to improve the cosmesis. In this chapter a right colectomy is described using the suprapubic scar as the main access to perform RPLS and also to remove the specimen from the abdomen at the end. This access remains under the bikini line, hence cosmetically acceptable. The procedure is performed using three reusable trocars inserted close each others in the same suprapubic incision, and curved reusable instruments. Each step is represented by specific drawings showing the internal triangulation, which characterizes the conventional multiport laparoscopy, and the external surgeon's ergonomy., SCOPUS: ch.b, info:eu-repo/semantics/published

In the last decade, a new philosophy to be less invasive in minimally invasive surgery and to perform laparoscopy without visible scars invested surgeons, researchers and companies. The purpose was basically the improved cosmesis, but the postoperative pain, the hospital stay, and the patient's convalescence were also attempted to be reduced. Natural orifices transluminal endoscopic surgery (NOTES) and single-port/single-incision laparoscopy (SPL/SLS) were the two principal fields of researches and investments. Due to the difficulties to perform the conventional multiport laparoscopic procedures through NOTES and sometimes also through SPL/SLS, a new philosophy to keeping in mind the desire of less invesivity of minimally invasive surgery started to be popular and named reduced port laparoscopic surgery (RPLS). In RPLS, the classic multiport laparoscopic procedures can be performed in a similar method, but through a reduced number of trocars, a reduced size of each trocar and use of needlescopic instruments. Furthermore, some intrabdominal devices can be inserted in the abdomen and used like an assistant's help or to improve the operative field's exposure. In this chapter two main antireflux procedures, Nissen fundoplication (360°) and Toupet fundoplication (270°), are described step by step using the transumbilical access, and curved reusable instruments. Each step is represented by specific drawings showing the internal triangulation, which characterizes the conventional multiport laparoscopy, and the external surgeon's ergonomy., SCOPUS: ch.b, info:eu-repo/semantics/published

In the last decade, a new philosophy to be less invasive in minimally invasive surgery and to perform laparoscopy without visible scars invested surgeons, researchers and companies. The purpose was basically the improved cosmesis, but the postoperative pain, the hospital stay, and the patient's convalescence were also attempted to be reduced. Natural orifices transluminal endoscopic surgery (NOTES) and single-port/single-incision laparoscopy (SPL/SLS) were the two principal fields of researches and investments. Due to the difficulties to perform the conventional multiport laparoscopic procedures through NOTES and sometimes also through SPL/SLS, a new philosophy to keeping in mind the desire of less invesivity of minimally invasive surgery started to be popular and named reduced port laparoscopic surgery (RPLS). In RPLS, the classic multiport laparoscopic procedures can be performed in a similar method, but through a reduced number of trocars, a reduced size of each trocar and use of needlescopic instruments. Furthermore, some intrabdominal devices can be inserted in the abdomen and used like an assistant's help or to improve the operative field's exposure. In this chapter two main antireflux procedures, Nissen fundoplication (360°) and Toupet fundoplication (270°), are described step by step using the transumbilical access, and curved reusable instruments. Each step is represented by specific drawings showing the internal triangulation, which characterizes the conventional multiport laparoscopy, and the external surgeon's ergonomy., SCOPUS: ch.b, info:eu-repo/semantics/published

With the advent of natural orifices translumena endoscopic surgery (NOTES) and single-port/single-incision laparoscopy (SPL/SLS), minimally invasive surgery recently underwent to an impressive evolution, mainly improving the cosmesis and reducing the abdominal wall trauma. A new concept to be less invasive in minimally invasive surgery started to be popular and named reduced port laparoscopic surgery (RPLS). A reduced number of trocars associated to a reduced size of each trocar and instrument chracterizes this new technique. During conventional multiport laparoscopic colorectal surgery, the specimen has to be retrieved, hence an enlargement of the trocar or a new opening of the abdominal wall is necessary. With NOTES, surgeons started to consider the natural orifices to remove the specimen from the abdomen (vagina/rectum), and with SPL/SLS to minimize the abdominal trauma and to improve the cosmesis. In this chapter a right colectomy is described using the suprapubic scar as the main access to perform RPLS and also to remove the specimen from the abdomen at the end. This access remains under the bikini line, hence cosmetically acceptable. The procedure is performed using three reusable trocars inserted close each others in the same suprapubic incision, and curved reusable instruments. Each step is represented by specific drawings showing the internal triangulation, which characterizes the conventional multiport laparoscopy, and the external surgeon's ergonomy., SCOPUS: ch.b, info:eu-repo/semantics/published

Background. Single-incision laparoscopy (SIL) has gained significance recently. The umbilicus has been the preferred access site for SIL. Suprapubic access site (SAS) can be an alternative, especially for a right hemicolectomy (RH). Methods. Between November 2011 and July 2012, 7 consecutive patients underwent suprapubic SIL RH (SSILRH). The median age was 53 years, and the median body mass index was 23.9 kg/m2. Indications for surgery included appendicular tumor (1) and adenocarcinoma of the right colon (6). Three reusable trocars were used, and the resection was performed through the SAS. An intracorporeal linear stapled anastomosis was performed, the mesenteric defect was closed, and the access site was used for specimen extraction. Results. No patient required additional trocars or conversion to an open surgery. The median laparoscopic time was 222 minutes, and the median final incision length was 50 mm. The median Visual Analogue Scale score (0-10) at 6, 18, 30, 42, 54, 66, and 78 postoperative hours was 6, 6, 2, 2, 2, 2, and 2, respectively. The median hospital stay was 4 days. Conclusions. SSILRH is useful because the SAS can be enlarged for extraction of the specimen without compromising the cosmetic outcome. The mesocolic and mesenteric dissections are on the same axis as the access site. The intracorporeal anastomosis can be performed without traction. Finally, positioning of the operative table improves exposure of the operative field and allows the surgeon to maneuver the colon and small bowel intracorporeally. © The Author(s) 2012., SCOPUS: ar.j, info:eu-repo/semantics/published

Background: Primary and incisional hernia can be repaired by multitrocar laparoscopy. Single-access laparoscopy (SAL) recently gained interest to decrease the invasiveness and to reduce the abdominal trauma, besides improved cosmetic results. The authors report first 50 patients who consulted for primary and incisional hernia and treated by SAL prosthetic repair. Patients and methods: Between December 2009 and March 2012, 50 patients (24 females, 26 males) were submitted to SAL for primary (23) and incisional hernia (27). Mean age was 49.1 ± 15.1 years (17-75), and mean body mass index 29.7 ± 5.7 kg/m2 (19-44.1). A total of 26 primary and 30 incisional hernias were treated. The technique consisted in implied the use of an 11-mm trocar for 10-mm scope, curved reusable instruments without trocars, and dualface prosthesis fixed by tacks without transfascial closures. Results: No conversion to open surgery nor addition of one or more trocars was necessary. Mean perioperative hernia sizes were 7.0 ± 5.0 cm (2-24) in length and 6.0 ± 3.4 cm (1-16) in width, for a surface of 55.0 ± 64.6 cm 2 (2.8-268.2). Mean prosthesis size used was 188.1 ± 113.4 cm2 (56.2-505.6). Mean laparoscopic time was 60.2 ± 32.8 min (26-153), and mean final scar length was 21.2 ± 4.5 mm (13-35). Mean hospital stay was 2.2 ± 1.2 days (1-8). Perioperative complications were registered in 4 patients and minor early complications in 13 patients of each group. After a mean follow-up of 16.1 ± 8.8 months (4-34), 2 late complications were observed in one patient of each group. Conclusion: Primary and incisional hernia can safely be treated by SAL prosthetic repair, but a learning curve is unavoidable. Thanks to this approach, in patients with primary hernia, only a small scar is finally visible, and in patients who proved to be prone to develop incisional hernia, the number of fascial incisions can be reduced. © 2012 Springer-Verlag France., SCOPUS: ar.j, info:eu-repo/semantics/published

Background: Primary and incisional hernia can be repaired by multitrocar laparoscopy. Single-access laparoscopy (SAL) recently gained interest to decrease the invasiveness and to reduce the abdominal trauma, besides improved cosmetic results. The authors report first 50 patients who consulted for primary and incisional hernia and treated by SAL prosthetic repair. Patients and methods: Between December 2009 and March 2012, 50 patients (24 females, 26 males) were submitted to SAL for primary (23) and incisional hernia (27). Mean age was 49.1 ± 15.1 years (17-75), and mean body mass index 29.7 ± 5.7 kg/m2 (19-44.1). A total of 26 primary and 30 incisional hernias were treated. The technique consisted in implied the use of an 11-mm trocar for 10-mm scope, curved reusable instruments without trocars, and dualface prosthesis fixed by tacks without transfascial closures. Results: No conversion to open surgery nor addition of one or more trocars was necessary. Mean perioperative hernia sizes were 7.0 ± 5.0 cm (2-24) in length and 6.0 ± 3.4 cm (1-16) in width, for a surface of 55.0 ± 64.6 cm 2 (2.8-268.2). Mean prosthesis size used was 188.1 ± 113.4 cm2 (56.2-505.6). Mean laparoscopic time was 60.2 ± 32.8 min (26-153), and mean final scar length was 21.2 ± 4.5 mm (13-35). Mean hospital stay was 2.2 ± 1.2 days (1-8). Perioperative complications were registered in 4 patients and minor early complications in 13 patients of each group. After a mean follow-up of 16.1 ± 8.8 months (4-34), 2 late complications were observed in one patient of each group. Conclusion: Primary and incisional hernia can safely be treated by SAL prosthetic repair, but a learning curve is unavoidable. Thanks to this approach, in patients with primary hernia, only a small scar is finally visible, and in patients who proved to be prone to develop incisional hernia, the number of fascial incisions can be reduced. © 2012 Springer-Verlag France., SCOPUS: ar.j, info:eu-repo/semantics/published

Background. Single-incision laparoscopy (SIL) has gained significance recently. The umbilicus has been the preferred access site for SIL. Suprapubic access site (SAS) can be an alternative, especially for a right hemicolectomy (RH). Methods. Between November 2011 and July 2012, 7 consecutive patients underwent suprapubic SIL RH (SSILRH). The median age was 53 years, and the median body mass index was 23.9 kg/m2. Indications for surgery included appendicular tumor (1) and adenocarcinoma of the right colon (6). Three reusable trocars were used, and the resection was performed through the SAS. An intracorporeal linear stapled anastomosis was performed, the mesenteric defect was closed, and the access site was used for specimen extraction. Results. No patient required additional trocars or conversion to an open surgery. The median laparoscopic time was 222 minutes, and the median final incision length was 50 mm. The median Visual Analogue Scale score (0-10) at 6, 18, 30, 42, 54, 66, and 78 postoperative hours was 6, 6, 2, 2, 2, 2, and 2, respectively. The median hospital stay was 4 days. Conclusions. SSILRH is useful because the SAS can be enlarged for extraction of the specimen without compromising the cosmetic outcome. The mesocolic and mesenteric dissections are on the same axis as the access site. The intracorporeal anastomosis can be performed without traction. Finally, positioning of the operative table improves exposure of the operative field and allows the surgeon to maneuver the colon and small bowel intracorporeally. © The Author(s) 2012., SCOPUS: ar.j, info:eu-repo/semantics/published

Introduction: Single-access laparoscopy has garnered growing interest in recent years in an attempt to improve cosmesis, reduce postoperative pain, and minimize abdominal wall trauma. Case Description: A female patient suffering from a symptomatic giant biliary cyst of the liver segments 4-7-8 was admitted for transumbilical single-access laparoscopic cyst unroofing. The procedure was performed using a standard 11-mm reusable trocar for a 10-mm, 30°- angled, rigid scope and curved reusable instruments inserted transumbilically without trocars. Operative time was 90 minutes, and the final incision length was 14 mm. The use of minimal pain medication permitted discharge on the third postoperative day, and after 25 months, the patient remains asymptomatic with a no visible umbilical scar. Conclusions: Giant biliary cysts can be removed by single-access laparoscopy. Because of this technique, surgeons work in ergonomic positions, and the cost of the procedure remains similar to that of the multitrocar technique. The incision length and the use of pain medication are kept minimal as well. © 2012 by JSLS., SCOPUS: ar.j, info:eu-repo/semantics/published