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The near-edge X-ray absorption fine structure (NEXAFS and X-ray photoelectron (XP) spectra of gas-phase 2,8-bis-(diphenylphosphoryl)dibenzo[b,d]thiophene (PPT) and triphenylphosphine oxide (TPPO) have been measured at the S and P L-II,L-III-edge regions. The time-dependent density functional theory (TDDFT) based on the relativistic two-component zeroth-order regular approximation approach has been used to provide an assignment of the experimental spectra, giving the contribution of the spin-orbit splitting and of the molecular-field splitting to the sulfur and phosphor binding energies. Computed XP and NEXAFS spectra agree well with the experimental measurements. In going from dibenzothiophene and TPPO to PPT, the nature of the most intense S 2p and P 2p NEXAFS features are preserved; this trend suggests that the electronic and geometric behaviors of the S and P atoms in the two building block moieties are conserved in the more complex system of PPT. This work enables us to shed some light onto the structure of the P-O bond, a still highly debated topic in the chemical literature. Since the S 2p and P 2p NEXAFS intensities provide specific information on the higher-lying localized sigma*(C-S) and sigma*(P-O) virtual MOs, we have concluded that P 3d AOs are not involved in the formation of the P-O bond. Moreover, the results support the mechanism of negative hyperconjugation, by showing that transitions toward sigma*(P-O) states occur at lower energies with respect to those toward it pi*(P-O) states.

BACKGROUNDSeveral studies have shown the safety, feasibility and oncologic adequacy of robotic right hemicolectomy (RRH). Laparoscopic right hemicolectomy (LRH) is considered technically challenging. Robotic surgery has been introduced to overcome this technical limitation, but it is related to high costs. To maximize the benefits of such surgery, only selected patients are candidates for this technique. In addition, due to progressive aging of the population, an increasing number of minimally invasive procedures are performed on elderly patients with severe comorbidities, who are usually more prone to post-operative complications.AIMTo investigate the outcomes of RRHvsLRH with regard to age and comorbidities.METHODSWe retrospectively analyzed 123 minimally invasive procedures (68 LRHsvs55 RRHs) for right colon cancer or endoscopically unresectable adenoma performed in our Center from January 2014 until September 2019. The surgical procedures were performed according to standardized techniques. The primary clinical outcome of the study was the length of hospital stay (LOS) measured in days. Secondary outcomes were time to first flatus (TFF) and time to first stool evacuation. The robotic technique was considered the exposure and the laparoscopic technique was considered the control. Routine demographic variables were obtained, including age at time of surgery and gender. Body mass index and American Society of Anesthesiologists physical status were registered. The age-adjusted Charlson Comorbidity Index (ACCI) was calculated; the tumor-node-metastasis system, intra-operative variables and post-operative complications were recorded. Post-operative follow-up was 180 d.RESULTSLOS, TFF, and time to first stool were significantly shorter in the robotic group: Median 6 [interquartile range (IQR) 5-8]vs7 (IQR 6-10.5) d,P= 0.028; median 2 (IQR 1-3)vs3 (IQR 2-4) d,P< 0.001; median 4 (IQR 3-5)vs5 (IQR 4-6.5) d,P= 0.005, respectively. Following multivariable analysis, the r

Context. Low-mass protostars drive powerful molecular outflows that can be observed with millimetre and submillimetre telescopes. Various sulfuretted species are known to be bright in shocks and could be used to infer the physical and chemical conditions throughout the observed outflows. Aims. The evolution of sulfur chemistry is studied along the outflows driven by the NGC 1333-IRAS4A protobinary system located in the Perseus cloud to constrain the physical and chemical processes at work in shocks. Methods. We observed various transitions from OCS, CS, SO, and SO2 towards NGC 1333-IRAS4A in the 1.3, 2, and 3 mm bands using the IRAM NOrthern Extended Millimeter Array and we interpreted the observations through the use of the Paris-Durham shock model. Results. The targeted species clearly show different spatial emission along the two outflows driven by IRAS4A. OCS is brighter on small and large scales along the south outflow driven by IRAS4A1, whereas SO2 is detected rather along the outflow driven by IRAS4A2 that is extended along the north east-south west direction. SO is detected at extremely high radial velocity up to + 25 km s-1 relative to the source velocity, clearly allowing us to distinguish the two outflows on small scales. Column density ratio maps estimated from a rotational diagram analysis allowed us to confirm a clear gradient of the OCS/SO2 column density ratio between the IRAS4A1 and IRAS4A2 outflows. Analysis assuming non Local Thermodynamic Equilibrium of four SO2 transitions towards several SiO emission peaks suggests that the observed gas should be associated with densities higher than 105 cm-3 and relatively warm (T > 100 K) temperatures in most cases. Conclusions. The observed chemical differentiation between the two outflows of the IRAS4A system could be explained by a different chemical history. The outflow driven by IRAS4A1 is likely younger and more enriched in species initially formed in interstellar ices, such as OCS, and recently sputter

Aims. The Seeds Of Life In Space IRAM/NOEMA large program aims at studying a set of crucial complex organic molecules in a sample of sources with a well-known physical structure that covers the various phases of solar-type star formation. One representative object of the transition from the prestellar core to the protostar phases has been observed toward the very low luminosity object (VeLLO) L1521F. This type of source is important to study to link prestellar cores and Class 0 sources and also to constrain the chemical evolution during the process of star formation. Methods. Two frequency windows (81.6-82.6 GHz and 96.65-97.65 GHz) were used to observe the emission from several complex organics toward the L1521F VeLLO. These setups cover transitions of ketene (H2CCO), propyne (CH3CCH), formamide (NH2CHO), methoxy (CH3O), methanol (CH3OH), dimethyl ether (CH3OCH3), and methyl formate (HCOOCH3). Results. Only two transitions of methanol (A+, E2) have been detected in the narrow window centered at 96.7 GHz (with an upper limit on E1) in a very compact emission blob (∼7″ corresponding to ∼1000 au) toward the northeast of the L1521F protostar. The CS 2-1 transition is also detected within theWideX bandwidth. Consistently with what has been found in prestellar cores, the methanol emission appears ∼1000 au away from the dust peak. The location of the methanol blob coincides with one of the filaments that have previously been reported in the literature. The excitation temperature of the gas inferred from methanol is (10 ± 2) K, while the H2 gas density (estimated from the detected CS 2-1 emission and previous CS 5-4 ALMA observations) is a factor >25 higher than the density in the surrounding environment (n(H2) ≥ 107 cm-3). Conclusions. Based on its compactness, low excitation temperature, and high gas density, we suggest that the methanol emission detected with NOEMA is (i) either a cold and dense shock-induced blob that formed recently (≤ a few hundred years) by infal

Peritoneal metastases (PM) from colorectal cancer (CRC) still represent a huge health-care problem. Recent population-based studies report an overall 3.5–4.2% incidence of CRC-PM after potentially curative primary surgery [1,2]. These rates can reach up to about 25% in locally advanced CRC penetrating visceral peritoneum (pT4a), or directly infiltrating surrounding organs (pT4b) [[1], [2], [3]]. Accordingly, the peritoneum is one of the most common site of metastatic spread for CRC, following the liver and lung, even though incidences may be likely underestimated because PM are more difficult to detect than liver or lung metastases. A strategy involving local-regionally delivered chemotherapy to prevent the outgrowth of occult peritoneal seeding into macroscopic metastases is supported by a strong rationale: first, cytoreductve surgery (CRS) combined with hyperthermic intraperitoneal chemotheray (HIPEC) improve CRC-PM survival, but most patients are not suitable for this demanding treatment due to extensive peritoneal involvement, systemic metastases, and/or poor clinical conditions. Second, CRS/HIPEC is maximally effective and safe when small-volume disease is treated. Third, in the palliative setting, modern systemic chemotherapy (s-CT) and targeted agents appear to be less effective for peritoneal metastatic CRC than non-peritoneal metastatic CRC. Finally, the absence of symptoms, as well as current limitations of imaging, hamper early diagnosis and treatment [3]. On these bases, the use of HIPEC for the prevention or early treatment of CRC-PM has been tested at different time-points, either simultaneously with primary surgery [[3], [4], [5]], at the time of second-look surgery after adjuvant s-CT [6], or as a staged procedure at 5–8 weeks postoperatively [7]. Since we were amongst the first groups to investigate the role of adjuvant HIPEC, we were surprised to read that in the COLOPEC randomized trial such a treatment approach failed to demonstrate improved peri

Ovarian cancer (OC) remains relatively rare, although it is among the top 4 causes of cancer death for women younger than 50. The aggressive nature of the disease and its often late diagnosis with peritoneal involvement have an impact on prognosis. The current scientific literature presents ambiguous or uncertain indications for management of peritoneal carcinosis (PC) from OC, both owing to the lack of sufficient scientific data and their heterogeneity or lack of consistency. Therefore, the Italian Society of Surgical Oncology (SICO), the Italian Society of Obstetrics and Gynaecology, the Italian Association of Hospital Obstetricians and Gynaecologists, and the Italian Association of Medical Oncology conducted a multidisciplinary consensus conference (CC) on management of advanced OC presenting with PC during the SICO annual meeting in Naples Italy, on September 10-11, 2015. An expert committee developed questions on diagnosis and staging work-up, indications, and procedural aspects for peritonectomy, systemic chemotherapy, and hyperthermic intraperitoneal chemotherapy for PC from OC. These questions were provided to 6 invited speakers who answered with an evidence-based report. Each report was submitted to a jury panel, representative of Italian experts in the fields of surgical oncology, gynecology, and medical oncology. The jury panel revised the reports before and after the open discussion during the CC. This article is the final document containing the clinical evidence reports and statements, revised and approved by all the authors before submission.

The starburst pi-conjugated molecule 4,4 ',4 ''-tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine (C57H48N4, m-MTDATA), based on triphenylamine (TPA) building blocks, is widely used in optoelectronic devices due to its good electron-donor characteristics. The electronic structure of m-MTDATA was investigated for the first time in the gas phase by means of PhotoElectron Spectroscopy (PES) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy. The combination of Density Functional Theory (DFT) calculations with the experimental spectra provides a comprehensive description of the molecular electronic structure. Moreover, by comparing the results with previous TPA measurements, we could shed light on how the electronic structure evolves when the molecular size is increased. We found that the C 1s photoelectron spectra of m-MTDATA and TPA are similar, due to the balance of the counter-acting effects of the electronegativity of the N atoms and the delocalization of the amine lone-pair electrons. In contrast, the increased number of N atoms (i.e. N lone pairs) in m-MTDATA determines a three-peak feature in the outermost valence binding energy region with strong contributions by the N 2p(z) orbitals. We also obtained a decrease of the HOMO-LUMO gap for m-MTDATA, which points to improved electron donating properties of m-MTDATA with respect to TPA.

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