Correction: α-Fe2O3/TiO2 3D hierarchical nanostructures for enhanced photoelectrochemical water splitting.

Correction for 'α-Fe2O3/TiO2 3D hierarchical nanostructures for enhanced photoelectrochemical water splitting' by Hyungkyu Han et al., Nanoscale, 2017, 9, 134-142, https://doi.org/10.1039/C6NR06908H.

Dye-sensitized TiO2 nanotube membranes act as a visible-light switchable diffusion gate.

Here we report that both-end open anodic TiO2 nanotube membranes, after sensitization with a Ru(ii)-based dye, exhibit visible-light switching properties for flow-through the nanotube channels. Under illumination, the gate is in an open state providing ∼four-times faster permeation of small molecules through the membrane compared to a dark state. Switching is reversible with no apparent dye degradation being observed. Gating is possible not only of permeating dye molecules but also of nanoprobes such as polystyrene nanospheres. Supported by quantitative modelling, we attribute the switching mechanism to light-induced changes of the charge distribution at the dye/TiO2 interface which in turn alters the hydrodynamics within the anodic tube membranes. This demonstrates that these simple dye-sensitized nanotube membranes can be used as an optically addressable flow-through gate in nanofluidics.

Hematite Photoanode with Complex Nanoarchitecture Providing Tunable Gradient Doping and Low Onset Potential for Photoelectrochemical Water Splitting.

Over the past years, α-Fe2 O3 (hematite) has re-emerged as a promising photoanode material in photoelectrochemical (PEC) water splitting. In spite of considerable success in obtaining relatively high solar conversion efficiency, the main drawbacks hindering practical application of hematite are its intrinsically hampered charge transport and sluggish oxygen evolution reaction (OER) kinetics on the photoelectrode surface. In the present work, we report a strategy that synergistically addresses both of these critical limitations. Our approach is based on three key features that are applied simultaneously: i) a careful nanostructuring of the hematite photoanode in the form of nanorods, ii) doping of hematite by Sn4+ ions using a controlled gradient, and iii) surface decoration of hematite by a new class of layered double hydroxide (LDH) OER co-catalysts based on Zn-Co LDH. All three interconnected forms of functionalization result in an extraordinary cathodic shift of the photocurrent onset potential by more than 300 mV and a PEC performance that reaches a photocurrent density of 2.00 mA cm-2 at 1.50 V vs. the reversible hydrogen electrode.

Photoanodes based on TiO2 and α-Fe2O3 for solar water splitting - superior role of 1D nanoarchitectures and of combined heterostructures.

Solar driven photoelectrochemical water splitting (PEC-WS) using semiconductor photoelectrodes represents a promising approach for a sustainable and environmentally friendly production of renewable energy vectors and fuel sources, such as dihydrogen (H2). In this context, titanium dioxide (TiO2) and iron oxide (hematite, α-Fe2O3) are among the most investigated candidates as photoanode materials, mainly owing to their resistance to photocorrosion, non-toxicity, natural abundance, and low production cost. Major drawbacks are, however, an inherently low electrical conductivity and a limited hole diffusion length that significantly affect the performance of TiO2 and α-Fe2O3 in PEC devices. To this regard, one-dimensional (1D) nanostructuring is typically applied as it provides several superior features such as a significant enlargement of the material surface area, extended contact between the semiconductor and the electrolyte and, most remarkably, preferential electrical transport that overall suppress charge carrier recombination and improve TiO2 and α-Fe2O3 photoelectrocatalytic properties. The present review describes various synthetic methods and modifying concepts of 1D-photoanodes (nanotubes, nanorods, nanofibers, nanowires) based on titania, hematite, and on α-Fe2O3/TiO2 heterostructures, for PEC applications. Various routes towards modification and enhancement of PEC activity of 1D photoanodes are discussed including doping, decoration with co-catalysts and heterojunction engineering. Finally, the challenges related to the optimization of charge transfer kinetics in both oxides are highlighted.

Laparoscopic Nerve-Preserving Sacropexy.

STUDY OBJECTIVE: To demonstrate our developed nerve-preserving technique during laparoscopic sacropexy (LSP) for multicompartment pelvic organ prolapse. DESIGN: A step-by-step demonstration of our surgical procedure on video (Canadian Task Force classification II-2). Informed consent was obtained from the subject, and the applicable Institutional Review Board provided approval. SETTING: Although sacropexy does remain the 'gold standard' procedure for apical prolapse [1], the subjective outcome of the procedure has been reported to be not so satisfactory as its anatomic outcome [2]. New onset bowel symptoms have been observed with voiding and sexual dysfunctions [3]. Published data revealed a correlation between iatrogenic denervation during LSP and postoperative dysfunctions [4-6]. We adopted a nerve-preserving approach with the aim of reducing the iatrogenic morbidity. INTERVENTIONS: Our surgical nerve-preserving LSP technique from the promontory down to the right uterosacral ligament and the rectovaginal space proceeds in 3 steps: Step 1: Opening the peritoneum. The peritoneum is opened just medial to the right common iliac artery, approximately 20 to 30 mm above the sacral promontory, allowing a safe approach in an area far from nerves and vascular structures. Peritoneal incision is extended toward the promontory. The underlying presacral fascia containing the right hypogastric nerve (rHN) is identified and incised longitudinally. The presacral fascia and the rHN are then pushed medially to expose the longitudinal anterior vertebral ligament; the finding of the middle sacral veins represents the limit of any further medial dissection. Opening and displacement of the prevertebral fascia are not mandatory. Step 2: Opening the peritoneum of the right pelvic sidewall, respecting the integrity of the presacral fascia and of the rHN contained within it. An inverted L-shaped peritoneal incision extending from the sacral promontory up to the left uterosacral ligament is completed, with care taken to preserve the rHN identified previously. In proximity to the uterus, the dissection line crosses the upper edge of the right uterosacral ligament at its proximal third and extends medially. The rectovaginal space is opened and joined to the peritoneal tunnel with a section of the superficial layer of the right uterosacral ligament, preserving its deep nervous portion. Step 3: Dissection of the rectovaginal space, respecting the integrity of the rectal fascia. The rectovaginal space is fully dissected, and at its caudal edge the dissection is carried out laterally to the rectum upward to identify the pelvic parietal fascia covering the levator ani muscle, in the middle to the cranial edge of the perineal body. Preservation of the rectal fascia prevents possible injury to the middle rectal vessels and the rectal branches of the inferior hypogastric plexus, which runs close to the pelvic floor. The complete dissection of the rectovaginal space appears in an inverted V-shaped space covering approximately two-thirds of the posterior vaginal wall, with the apex at the convergence of the uterosacral ligaments. The procedure is completed with dissection of the vesicovaginal space through the creation of an avascular triangular-shaped space with the apex at the dorsal end of the bladder trigone and laterally limited by the superficial vascular layer of the vesicouterine ligaments. The bladder branches of the inferior hypogastric plexus run far from the surgical field in the deep portion of the vesicouterine ligaments. CONCLUSION: A nerve-sparing approach to pelvic spaces during LSP is feasible following well-defined surgical steps, which allow the surgeon to visualize all of the nerve pathways and potentially dangerous anatomic structures.

α-Fe2O3/TiO2 3D hierarchical nanostructures for enhanced photoelectrochemical water splitting.

We report the fabrication of 3D hierarchical hetero-nanostructures composed of thin α-Fe2O3 nanoflakes branched on TiO2 nanotubes. The novel α-Fe2O3/TiO2 hierarchical nanostructures, synthesized on FTO through a multi-step hydrothermal process, exhibit enhanced performances in photo-electrochemical water splitting and in the photocatalytic degradation of an organic dye, with respect to pure TiO2 nanotubes. An enhanced separation of photogenerated charge carriers is here proposed as the main factor for the observed photo-activities: electrons photogenerated in TiO2 are efficiently collected at FTO, while holes are transferred to the α-Fe2O3 nanobranches that serve as charge mediators to the electrolyte. The morphology of α-Fe2O3 that varies from ultrathin nanoflakes to nanorod/nanofiber structures depending on the Fe precursor concentration was shown to have a significant impact on the photo-induced activity of the α-Fe2O3/TiO2 composites. In particular, it is shown that for an optimized photo-electrochemical structure, a combination of critical factors should be achieved such as (i) TiO2 light absorption and photo-activation vs.α-Fe2O3-induced shadowing effect and (ii) the availability of free TiO2 surface vs.α-Fe2O3-coated surface. Finally, theoretical analysis, based on DFT calculations, confirmed the optical properties experimentally determined for the α-Fe2O3/TiO2 hierarchical nanostructures. We anticipate that this new multi-step hydrothermal process can be a blueprint for the design and development of other hierarchical heterogeneous metal oxide electrodes suitable for photo-electrochemical applications.

Accuracy of a new diagnostic tool in deep infiltrating endometriosis: Positron emission tomography-computed tomography with 16α-[18F]fluoro-17ß-estradiol.

AIM: Preoperative workup of deep infiltrating endometriosis is limited in the evaluation of extragenital and extrapelvic disease and in distinguishing between the previous surgical scar and active lesion. Histological verification remains the gold standard for diagnosis. The aim of this study was therefore to evaluate positron emission tomography-computed tomography (PET/CT) with an experimental estrogen receptor tracer (16α-[18F]fluoro-17ß-estradiol; [18F]FES) for accurate staging and non-invasive diagnosis of the disease. The primary endpoint was the feasibility of this tool on comparison with histology. The secondary endpoint was the accuracy of PET/CT in comparison with magnetic resonance imaging (MRI). METHODS: Four eligible subjects with extragenital endometriosis underwent MRI, PET/CT with [18F]FES, and laparoscopic excision of endometriosis in the same month. Region-by-region analysis was used to compare the findings of the two diagnostic tools with surgical histological specimens obtained during laparoscopy. RESULTS: A total of 40 anatomical regions were examined: seven were [18F]FES positive, four were positive on MRI and eight positive on histology. A total of nine regions were discordant. PET/CT agreed with histology in 9/9 of the discrepant findings. CONCLUSION: PET/CT with [18F]FES was feasible and had greater accuracy than MRI, particularly in patients with previous surgery. Further studies are needed, however, to investigate its role in bowel endometriosis in sites other than recto-sigmoid junction, nerve localization, and subcentimetric disease.

Feasibility and Acceptability of Office-Based Polypectomy With a 16F Mini-Resectoscope: A Multicenter Clinical Study.

STUDY OBJECTIVE: To investigate the feasibility and acceptability of office hysteroscopic polypectomy using a novel continuous-flow operative 16F mini-resectoscope. DESIGN: Multicenter prospective case series (Canadian Task Force classification III). SETTING: "SS Antonio e Biagio" Hospital, Alessandria, and University "Federico II" of Naples. PATIENTS: One hundred eighty-two patients with endometrial polyps. INTERVENTIONS: Hysteroscopic polypectomy performed with 16F mini-resectoscope in an office setting, without analgesia and/or anesthesia. MEASUREMENTS AND MAIN RESULTS: Polypectomy was successfully performed in 175 patients in a single surgical step (96.15%), with only 1 patient (.54%) requiring a second office surgical step to complete the surgery. Seven patients (3.84%) were excluded from the analysis of operative parameters because of severe pelvic pain during the office procedure, which required a second inpatient surgical step. No major complications were recorded. CONCLUSION: Our findings demonstrate that removal of endometrial polyps using the 16F mini-resectoscope in an office setting is a feasible and safe surgical option. Outpatient see-and-treat polypectomy is an acceptable and effective alternative to inpatient resectoscopic polypectomy.

Aligned metal oxide nanotube arrays: key-aspects of anodic TiO2 nanotube formation and properties.

Over the past ten years, self-aligned TiO2 nanotubes have attracted tremendous scientific and technological interest due to their anticipated impact on energy conversion, environment remediation and biocompatibility. In the present manuscript, we review fundamental principles that govern the self-organized initiation of anodic TiO2 nanotubes. We start with the fundamental question: why is self-organization taking place? We illustrate the inherent key mechanistic aspects that lead to tube growth in various different morphologies, such as ripple-walled tubes, smooth tubes, stacks and bamboo-type tubes, and importantly the formation of double-walled TiO2 nanotubes versus single-walled tubes, and the drastic difference in their physical and chemical properties. We show how both double- and single-walled tube layers can be detached from the metallic substrate and exploited for the preparation of robust self-standing membranes. Finally, we show how by selecting specific growth approaches to TiO2 nanotubes desired functional features can be significantly improved, e.g., enhanced electron mobility, intrinsic doping, or crystallization into pure anatase at high temperatures can be achieved. Finally, we briefly outline the impact of property, modifications and morphology on functional uses of self-organized nanotubes for most important applications.

A Safe and Simple Laparoscopic Cold Knife Section Technique for Bulky Uterus Removal.

BACKGROUND: Morcellation of a bulky uterus after total laparoscopic hysterectomy (TLH) is a challenge for those dealing with advanced laparoscopic surgery. However, there are no laparoscopic standardized procedures available to date. We developed a laparoscopic cold knife technique with the aim of demonstrating a simple and reproducible method of sectioning and vaginal retrieval of the bulky uterus. MATERIALS AND METHODS: From June 2012 to June 2014, patients who underwent TLH for benign indication, with a uterus size over 12 gestational weeks, were prospectively admitted into the clinical study. Before specimen vaginal retrieval, uterine section was achieved by Chardonnens' cold knife with the aim of obtaining two uterus halves sectioned longitudinally and held together only by the posterior cervical wall. We performed the procedure in a containment system to avoid myometrial spillage into the abdomen. RESULTS: Twenty-nine women with a bulky uterus were treated by TLH and the cold knife section technique. The uterine size ranged from 240 to 850 g (median, 460 g), and the average morcellation operative time was 11.3 minutes. All procedures were completed successfully without complications. CONCLUSIONS: Our data suggest that the cold knife uterine section technique after TLH is a feasible, simple, and reproducible method of bulky uterus morcellation, even if further research is advisable to fully evaluate the advantages of this procedure.

Homogeneous reduction of CO2 by photogenerated pyridinyl radicals.

We report that 1-hydropyridinyl radicals (1-PyH(•)) photogenerated in solution react with dissolved CO2 en route to its 2e(-) reduction into carboxylic acids. The 254 nm excitation of pyridine (Py) in deaerated 2-PrOH/H2O mixtures saturated with 1 atm of CO2 yields a suite of products, among which we identified Na(HCOO)2(-) (m/z(-) = 113), C5H6NCOO(-) (m/z(-) = 124), and C5H10O2NCOO(-) (m/z(-) = 160) species by electrospray ionization mass spectrometry. These products demonstrably contain carboxylate functionalities that split CO2 neutrals via collisionally induced dissociation. We infer that 1-PyH(•) [from (1) (3)Py* + 2-PrOH → 1-PyH(•) + (•)PrOH] adds to CO2, in competition with radical-radical reactions, leading to intermediates that are in turn reduced by (•)PrOH into the observed species. The formation of carboxylates in this system, which is shown to require CO2, Py, 2-PrOH, and actinic radiation, amounts to the homogeneous 2e(-) reduction of CO2 by 2-PrOH initiated by Py*. We evaluate a rate constant (2) k2(1-PyH(•) + CO2 → (•)Py-1-COOH) ≈ O (10) M(-1) s(-1) and an activation energy E2 ≥ 9 kcal mol(-1) that are compatible with thermochemical estimates for this reaction.

A safe method of vaginal longitudinal morcellation of bulky uterus with endometrial cancer in a bag at laparoscopy.

BACKGROUND: Total laparoscopic hysterectomy (TLH) is becoming an increasingly popular treatment in endometrial cancer. Intra-abdominal or vaginal uterus morcellation are well described and routinely practiced techniques in removing a benign bulky uterus but contraindicated in endometrial cancer. In malignancy, the uterus needs to be removed intact to avoid intraperitoneal spillage of the endometrial cancer cells, and a uterine size of 12 gestational weeks (g.w.) or larger has been considered a contraindication for the laparoscopic approach. The aim of our study was to evaluate the feasibility and safety of a sealed vaginal morcellation technique in a bag for endometrial cancer laparoscopic treatment. METHODS: We prospectively scheduled 12 patients affected by endometrial cancer with uterus bigger than 12 g.w. for endometrial cancer laparoscopic treatment. After performing TLH, a sterile plastic wrapping bag was inserted by a 12 mm camera port by rolling it onto the blunt probe. The uterus was covered from the fundus to the cervix, placing the free edges of the bag down into the manipulator cup with two blunt graspers. The specimen completely covered by the bag was then pushed down under direct laparoscopic vision through colpotomy and pulled out from the vagina. The uterus was morcellated by the vaginal route. RESULTS: All patients underwent laparoscopic treatment with vaginal uterine morcellation. The mean uterus weight was 290.8 ± 79.7 g with a mean morcellation operative time of 12.1 min. All vaginal morcellations were completed successfully. All patients were without evidence of local or distant recurrence at the median follow-up time of 18 months. CONCLUSIONS: This technique allows the surgeon to morcellate a bulky uterus in cases of endometrial cancer and reduces the chance of neoplastic cell spillage during debulking at TLH. Vaginal morcellation following oncologic rules permits a rapid uterine extraction and may avoid a number of unnecessary laparotomies.

Advanced utero-vaginal prolapse and vaginal vault suspension: synthetic mesh vs native tissue repair.

PURPOSE: To compare prosthetic and ligament vaginal vault suspension at vaginal hysterectomy in patients, with utero-vaginal stage III-IV pelvic organ prolapse quantification. METHODS: A retrospective case-control study was designed to compare 61 patients who had undergone Posterior intravaginal slingplasty (PIVS) with 61 patients in a matched control group who had undergone uterosacral ligament suspension (ULS). The primary outcome was to compare anatomic vaginal vault failure rate. The secondary outcomes were subjective cure and cure without adverse events. RESULTS: Follow-up mean duration for the PIVS and ULS groups was 56.2 and 57.7 months, respectively. Recurrent vault prolapse was observed more frequently in the ULS group with pre-intervention stage IV prolapse (0 vs 14.8 %; p = 0.04), while there was no difference in prolapse recurrence at any vaginal site. Although the subjective cure of PIVS and ULS was superimposable (91.8 vs 86.9 %; p = 0.25), there was a significantly higher cure rate, without adverse events, in the ULS group (90.2 vs 100 %; p = 0.01). CONCLUSIONS: Non-mesh vaginal vault repair should be considered the first-line measure at vaginal hysterectomy; prosthetic repair should be used for therapeutic purposes in patients with vaginal vault recurrence and considered at vaginal hysterectomy only in selected subjects with complete utero-vaginal eversion.

New mini-resectoscope: analysis of preliminary quality results in outpatient hysteroscopic polypectomy.

PURPOSE: We investigated the feasibility and acceptability of office hysteroscopic polypectomy using a new continuous-flow operative 16 Fr Gubbini's mini-resectoscope. This is a prospective clinical study (Canadian Task Force classification III). METHODS: The office hysteroscopic polypectomy was performed with a mini-resectoscope without analgesia or anesthesia. We evaluated the polyp size and the number, the effectiveness of resection, the operating time, the pelvic pain and complications. RESULTS: The office hysteroscopic polypectomy was successfully performed in all 33 patients. The polyps ranged in size from 5 to 50 mm with a mean of 18.15 ± 11.45 mm. We analyzed the operating time with a mean of 11.45 ± 4.71 min: 29 procedures took less than 15 min from the start of vaginoscopy to the end of surgery. Overall mean visual analog scale (VAS) calculated was 2.48 ± 1.37 (range 0-6). The correlation between the size of the polyps and operating time was statistically significant (p < 0.001). No major complications were recorded. CONCLUSION: Our preliminary data demonstrated that can be possible to remove endometrial polyps by hysteroscopy, using the mini-resectoscope, in an office setting. All procedures were completed successfully and well tolerated with a little discomfort permitting the removal also of big sized polyps without a statistical correlation between VAS and size of polyps or operating time. The outpatient polypectomy is a less-costing procedure and represents an acceptable and effective alternative to inpatient resectoscopic polypectomy, leading to a complete polyp excision in nearly all patients.

Labour induction at term: clinical, biophysical and molecular predictive factors.

PURPOSE: The aim of this multicentric study is to compare clinical, biophysical and molecular parameters in the prediction of the success of labour induction with prostaglandins. METHODS: We included 115 women, who underwent to labour induction at term with vaginal prostaglandin gel. We evaluated the diagnostic efficiency of endocervical phosphorylated insulin-like growth factor-binding protein (phIGFBP-1), cervicovaginal interleukins 6 (IL-6) and 8 (IL-8). We analyzed the transvaginal sonographic measurement of cervical length. A receiver-operating characteristics (ROC) curve was used to determine the most useful cut-off point. A multivariate logistic regression model was used to analyze the combination of significant predictive variables following univariate analysis. We analyzed all the data searching for the parameters that best predict the beginning of the active phase of labour within 12 h. RESULTS: 36.5 % of the patients delivered within 12 h. The Bishop score was >4 in the 43 % of patients with an active phase. The best cut-off values at ROC curves for cervical length, IL-6 and IL-8 were respectively 22 mm, 5 mg/dl and 20,237 mg/dl. At univariate analysis, all predictors of success, with the exception of IL-6, were significantly associated with the beginning of the active phase. Multivariate analysis of the Bishop score (OR 2.3), phIGFBP-1 test (OR 11.2) and IL-8 (OR 6.6) showed that the variables were independent and therefore useful in combination to predict the success of labour induction. CONCLUSION: The phIGFBP-1 test is a fast and easy test that can be used with Bishop score and IL-8 to reach an high positive predictive value in the prediction of the success of labour induction with prostaglandins.

Combination of biochemical markers in predicting pre-term delivery.

PURPOSE: The aim of this study was to evaluate the predictive performances of some biochemical markers in predicting pre-term delivery in asymptomatic women. METHODS: We included 491 asymptomatic women at 24 weeks' gestation, who underwent the endocervical phosphorylated insulin-like growth factor binding protein (phIGFBP-1) test, cervico-vaginal interleukins 6 (IL-6) and 8 (IL-8), and serum C-reactive protein (CRP). A receiver-operating characteristics (ROC) curve was used to determine the most useful cut off point. A multivariate logistic regression model was used in order to analyze the combination of significant predictive variables for pre-term delivery following univariate analysis. RESULTS: ROC curves indicated that 33 µg/l was the optimal cut off value for phIGFBP-1 test, 21.3 ng/l for IL-6, 324 ng/l for IL-8, and 8.42 mg/l for CRP in predicting pre-term delivery. The univariate logistic regression analyses revealed an odds ratio of 3.04 for phIGFBP-1 test, 4.82 for IL-6, and 3.08 for CRP. The multivariate analysis of phIGFBP-1 test, IL-6, and CRP showed that they were independent variables and therefore useful in combination for predicting pre-term delivery. CONCLUSIONS: The phIGFBP-1 test, the cervico-vaginal IL-6, and the serum CRP are independent variables that can be used together to predict pre-term delivery in asymptomatic women.

Vaginal hysterectomy and multimodal anaesthesia with bipolar vessel sailing (Biclamp(®) forceps) versus conventional suture technique: quality results' analysis.

PURPOSE: The medical and economic benefits of the transvaginal approach over the abdominal and laparoscopic methods are demonstrated in many studies. Vaginal hysterectomy with bipolar vessel sailing (BiClamp(®)) represents an example of mininvasive surgery and could be a valid and cost-benefit alternative in the surgical treatment of benign gynaecologic disease. BiClamp(®) may be carried out according to Clavè's technique with a good result in postoperative pain. METHODS: Prospective randomized study (Canadian Task Force classification I). We compared the vaginal hysterectomy with salpingo-oophorectomies with BiClamp(®) and multimodal anaesthesia (group A 30 patients) with vaginal hysterectomy with salpingo-oophorectomies and spinal anaesthesia (group B 30 patients). RESULTS: The median operating time was 33.5 min for group A and 54.5 min for group B (p < 0.0001). The median blood loss was 59.25 ml in group A and 81.75 ml in group B. The median hospital stay was 1.6 ± 0.58 days for group A and 2.55 ± 0.66 days for group B. Postoperative pain was statistically different between groups in the immediate postoperatory times, at 2 and at 6 h from the surgery and at 10 p.m. (p < 0.0001). Analyses of cost-effectiveness have stated advantages in terms of costs and indirect-direct benefits but also in earlier resumption of working. CONCLUSIONS: BiClamp(®) technique with multimodal anaesthesia has advantages from surgical, anaesthesiology and economic point of view. It is a minimally invasive surgery characterised by lower morbidity, quicker surgery times and reduced costs when compared to classical vaginal hysterectomy. BiClamp(®) technique represents a new border in vaginal surgery.