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We report here the preparation and characterization of two families of RP 2D perovskites including linear monoammonium cations, namely (CnH2n+1NH3)2PbBr4 and (CnH2n+1NH3)2PbI4 with n = 4, 6, 8, 10, 12, 14 and 16.

Impact of target visceral vessel anatomical configuration on early complicatins following endovascular repair of thoracoabdominal aortic aneurysms Objectives: Fenestrated and branched endovascular aortic repair (fEVAR-bEVAR) is a viable treatment option for thoracoabdominal aortic aneurysms but target visceral stent (TVS) endoleak and thrombosis remain a limiting factor. This study aims to evaluate TVS anatomy impact on one-year risk of thrombosis and endoleak. Methods: Patients treated with fEVAR-bEVAR for thoracoabdominal aneurysms between 2008-2020 in our centre were enrolled. We recorded comorbidities, operative details, one-month postoperative CT scan (anatomical reference), and TVS behaviour: thrombosis and endoleak at one-year follow-up. For each TVS, different points were identified using a centre-lumen-line: (A) TVS origin, (B) end of branch/fenestration, (C) visceral vessel entry, (D) end of TVS, (E) 1-cm distally. We analyzed TVS tortuosity ((centre-lumen-line/straight distance)-1, in %), image vector analysis of each segment in 2D (antero-posterior, left-right) and 3D (craneo-caudal displacement), and centre-lumen-line analysis (bending in ABC and CDE). Three independent observers performed a blind analysis, and anatomical differences between bEVAR/fEVAR, and cases with/without 1-year thrombosis and TVS endoleak, were compared using Kaplan-Meier curves (Log-Rank test), and T-Test/Wilcoxon signed-ranks test respectively. Results: 54 patients (72±713 years mean age; 182 TVS: 50 branches, 132 fenestrations) met the inclusion criteria. bEVAR cases had longer stents, with more caudal 3D angulation and greater ABC angulated segment. After excluding bEVAR cases (low case number), 97 fEVAR TVS were analyzed. Five thrombosis and seven endoleaks were observed. While anatomical configuration showed no association to thrombosis, it was related to endoleak: these cases presented more tortuous stents (5.97%±0.10, 21.40%±0,22, P=.011), with more angulated centre-lumen-line at ABC segment (5.69°±15.77°, 7.18°±7.77°, P=.012), and more upward-pointing stents in the origin of the stent (AB: 89.07°±24.46°, 109.09°±16.56°, P=.012; BC: 87.86°±21.10°, 113.11°±22.23°, P=.026). Conclusions: Anatomical configuration of the TVS is associated with stent type I-III endoleak, but not thrombosis, at one-year following fEVAR. Cases with endoleak presented more tortuous stents, with a more angulated exit from the endograft and upward-pointing of the origin of the stent.

The templating role in the formation of 2D metal halide perovskites of diammonium cations, such as 1,3-phenylenediammonium, 1,3-xylylenediammonium, 1,4-phenylenediammonium, and 1,4-xylylenediammonium cations, has been investigated.

There is increasing interest in the role of metal halide perovskites for heterogeneous catalysis. Here, we report a Ge-based 2D perovskite material that shows intrinsic water stability realized through organic cation engineering. Incorporating 4-phenylbenzilammonium (PhBz) we demonstrate, by means of extended experimental and computational results, that PhBz2GeBr4 and PhBz2GeI4 can achieve relevant air and water stability. The creation of composites embedding graphitic carbon nitride (g-C3N4) allows a proof of concept for light-induced hydrogen evolution in an aqueous environment by 2D Ge-based perovskites thanks to the effective charge transfer at the heterojunction between the two semiconductors.

We report here the preparation and characterization of two families of RP 2D perovskites including linear monoammonium cations, namely (CnH2n+1NH3)2PbBr4 and (CnH2n+1NH3)2PbI4 with n=4, 6, 8, 10, 12, 14 and 16. Structural and optical properties shows some similarities between the two series of samples with, however, distinct features related to the presence of phase transitions occurring when different ligands are present. Optical properties confirm a general blue-shift for the (CnH2n+1NH3)2PbBr4 system with respect to the (CnH2n+1NH3)2PbI4 family with the PL data showing two distinct variation paths for their excitonic emission behavior, one directly related to the chain length and another one depending on the ammonium coordination to the halogen atoms. Water stability of (CnH2n+1NH3)2PbBr4 and (CnH2n+1NH3)2PbI4 has been assessed and the results show an improved hydrophobicity by increasing the number of carbon atoms of the alkyl chain as well as by moving from iodide to bromide perovskites.

g-C3N4/metal halide perovskite composites were prepared and used for the first time as photocatalysts for in situ1O2 generation to perform hetero Diels–Alder, ene and oxidation reactions with suitable dienes and alkenes. The standardized methodology was made applicable to a variety of olefinic substrates. The scope of the method is finely illustrated and the reactions afforded desymmetrized hydroxy-ketone derivatives, unsaturated ketones and epoxides. Some limitations were also observed, especially in the case of the alkene oxidations, and poor chemoselectivity was somewhere observed in this work which is the first application of MHP-based composites for in situ1O2 generation. The experimental protocol can be used as a platform to further expand the knowledge and applicability of MHPs to organic reactions, since perovskites offer a rich variety of tuning strategies which may be explored to improve reaction yields and selectivities.

The role of templating the formation of 2D metal halide perovskites has been investigated by considering the 1,3-phenylenediammonium (1,3-PDA), 1,3-xylylenediamimonium (1,3-XDA), 1,4-phenylenediammonium (1,4-PDA), and 1,4-xylylenediamimonium (1,4-XDA) cations in lead bromide systems. Single-crystal x-ray diffraction confirms the formation 2D Dion-Jacobons (DJ) perovskites for all the cations except for the 1,3-XDA cation leading to a so-called 0D perovskitoid. Analysis of the structural data showed a higher distortion degree for the systems containing the shorter cation, namely 1,4-PDA. A detailed spectroscopic investigation, with both static and time resolved photoluminescence spectroscopy, revealed a broadband emissive component at room temperature with hundreds of nanometers of bandwidth when 1,3-PDA and 1,4-PDA cations are present, while a narrow peak is found for the longer cation, i.e. 1,4-XDA. A broadband emission arises in this last sample as well by decreasing temperature. Such broad emission, as indicated by the analysis of the power and temperature dependence of the PL, can be attributed to trap-mediated excitonic recombination or STEs, and the trend in emissive properties can be correlated to the different level of octahedral distortions. The novel systems reported in this work enlarge the family of broadband emitters and add further clues to develop efficient perovskite-based broadband and white light emitters.

Cultural branding acknowledges brands’ power as cultural artifacts that infuse culture with meanings and absorb new meanings from culture. The last mile of brand humanization sees brands act as citizens that construct their meanings through taking active part in socio-political discourse. This participation has been magnified and challenged by digital platforms that activate clicktivism practices to propagate cultural values. Our study is aimed at exploring how clicktivism is currently being leveraged by brands to achieve cultural relevance. We set our study in the clicktivist engagement solicited by the political mandate of Donald Trump, as numerous brands saw in Trump’s contested political agenda an opportunity to stand up and achieve cultural relevance. We term this new brand activism and its temporal dynamics as “instant cultural branding”, pointing at branding initiatives that apply fast, real time communication logics to get organically embedded in technomediated conversations with consumers, leveraging on cogent socio-cultural and political issues. Our findings reveal how, despite ambivalence of perceived authenticity of brand discourse can cause strong consumer criticism in digital conversations, deliberate ambiguity of instant cultural branding proves to be a trigger of clicktivist engagement. Ambiguity in taking socio-political stance resonates with the cultural norms of contemporary shifting consumers’ activism and ideology. Hence, controversial clicktivism emerges as a new dimension of cultural relevance in the fast temporality of technomediated discourse.

Tin halide perovskites have the potential to overcome the toxicity issues of lead-based systems for photovoltaic devices. Elucidation of local structural features in these systems is of fundamental relevance to better understand the optoelectronic properties. This has been realized in ASnX3 (A= MA, FA, and X= I, Br) by total scattering and X-ray pair distribution function analysis, showing a trend of increasing local distortion as a function of organic cation, halide and temperature.

The formation of postaortic coarctation aneurysms (pCoAA) is well-described in the literature and carries a significant risk of rupture and death. Treatment strategies include open surgical, hybrid, and endovascular repair, depending on the clinical presentation, risk assessment, and anatomy. The aim of this study was to report the early and midterm results of open surgical and endovascular repair of pCoAA.This is an international multicenter retrospective study including patients who underwent open surgical or endovascular repair for pCoAA between 2000 and 2021 at 14 highly specialized academic cardiovascular centers. The preoperative, intraoperative, and postoperative data were recorded and analyzed.A total of 74 patients (46 male; median age, 44 years; interquartile range [IQR], 35-53 years) underwent pCoAA repair. All patients had previously undergone surgical repair of aortic coarctation at a median age of 11 years for the index procedure (IQR, 7-17 years). The most common first surgical correction was synthetic patch aortoplasty in 48 patients, followed by graft interposition in 11. The median pCoAA diameter was 54 mm (IQR, 44-63 mm). The median time from the aortic coarctation repair to the pCoAA diagnosis was 33 years (IQR, 25-40 years). A total of 33 patients had symptoms at presentation, including thoracic or back pain in 8 patients. Open surgical repair was performed in 28 patients, including four frozen elephant trunk procedures and one Bentall. The remaining 46 patients underwent endovascular repair of the pCoAA. Two in-hospital deaths were observed (one frozen elephant trunk and one endovascular). After a median follow-up of 50 months (IQR, 14-127 months), there were a total of seven reinterventions.This international multicenter study demonstrates that patients with pCoAA can be safely treated with either open surgical or endovascular interventions. Because the median time between the coarctation repair and the aneurysm formation was more than 30 years, life-long surveillance of these patients is warranted.

The application of an external pressure on Metal Halide Perovskite (MHPs) has become a fascinating way of tuning their optical properties, achieving also novel features. Here, the pressure response of 2D MHPs including a long alkyl chain made of ten carbon atoms, namely decylammonium (DA), has been investigated as a function of the central atom in DA2PbI4 and DA2GeI4. The two systems share a common trend in the phase stability, displaying a transition from an orthorhombic to a monoclinic phase around 2 GPa, followed by a phase separation in two monoclinic phases characterized by different c-axis. The optical properties show rather different behavior due to the presence of Pb or Ge. DA2PbI4 shows a progressive red shift of the band gap from 2.28 eV at ambient conditions, to 1.64 eV at 11.5 GPa, with a narrow PL emission composed by two components, with the second one appearing in concomitance with the phase separation and significantly shifted to lower energy. On the other hand, DA2GeI4, changes from a non-PL system at ambient pressure, to a clear broadband emitter centered around 730 nm (FWHM ~ 170 nm), with a large stoke shift, and an intensity maximum at about 3.7 GPa. This work sheds light on the structural stability of 2D perovskites characterized by extended alkyl chains, to date limited to four carbon atoms, and shows the pressure-induced emergence of broad emission in a novel lead-free perovskite, DA2GeI4. The evidence of wide emission by a moderate pressure in a germanium-based 2D MHP represents a novel result which may open the design, by chemical pressure, of efficient wide or even white lead-free emitters.

Manipulation by external pressure of the optical response of 2D Metal Halide Perovskites (MHPs) is a fascinating route to tune their properties and promote the emergence of novel features. We investigate here DA

Purpose This paper aims to investigate the conceptualisation of corporate communication management (CCM) and its dimensionality from the practitioners’ perspectives. It proposes to validate an operational definition and dimensions of the CCM construct, which have not been identified in the literature. Design/methodology/approach The initial concepts are based on academic literature and followed by 12 face-to-face interviews with corporate communication practitioners and consultants from Malaysia to confirm the practicality of each dimension. QSR Nvivo Version 9.0 software is used to analyse the qualitative data. Then, the data are classified through deductive content analysis based on key words or themes. Findings The diverse perspectives are shown from the practitioners and consultants on the dimensionality of CCM. Most of the interviewees suggest that CCM dimensions include corporate advertising, corporate affairs, investor relations and employee communication within the corporate communication and other departments. They also found the public relations and media relations are clearly under corporate communications manager’s supervision. This research confirms the concept of CCM and its dimensionality to operationalise the CCM construct. The CCM dimensions also offer opportunities for further research to develop the measurement scales. Originality/value This research contributes to the clarification on the subject matter by developing clear concepts of the CCM and by offering insights about the role of the CCM dimensions, which help managers to more successfully incorporate the CCM dimension into the corporate management strategy. This paper also examines the concept of CCM and confirms its dimensionality, which helps in developing the CCM measurement for further quantitative research.

Perovskites are attracting an increasing interest in the wide community of photovoltaics, optoelectronic, and detection, traditionally relying on lead-based systems. This Minireview provides an overview of the current status of experimental and computational results available on Ge-containing 3D and low-dimensional halide perovskites. While stability issues analogous to those of tin-based materials are present, some strategies to afford this problem in Ge metal halide perovskites (MHPs) for photovoltaics have already been identified and successfully employed, reaching efficiencies of solar devices greater than 7 % at up to 500 h of illumination. Interestingly, some Ge-containing MHPs showed promising nonlinear optical responses as well as quite broad emissions, which are worthy of further investigation starting from the basic materials chemistry perspective, where a large space for properties modulation through compositions/alloying/fnanostructuring is present.

Objective Branched and fenestrated endografts (fEVAR/bEVAR) are complex techniques used to treat thoracic aorta pathologies involving the aortic arch. This systematic review aims to determine all the reported results regarding these techniques in the aortic arch, in order to describe their clinical outcomes. Methods A systematic review of the literature was performed, considering all articles published until October 2019. PubMed, Cochrane database resources were used. The protocol of the study was previously registered in the Prospero database (CRD42020147037). Primary exclusion criteria included opinion articles, merely technique descriptions, articles without the follow-up of at least 1 month, studies conducted on animals, mixed treatments, and ongoing trials without published data. Included variables were study design, aortic pathology, type of endovascular technique (fEVAR/bEVAR), endograft manufacturing, number of fenestrations/branches and type of bridge stents. Technical success, complications during surgery and follow-up were also described. Results From a total of 164 articles, 29 (28 retrospective, 1 prospective) were analyzed with a total of 693 cases (341 fEVAR and 352 bEVAR). The most common indications for repair were aneurysm (54.8%) and dissection (40%). Only fEVAR and bEVAR were considered, but different endograft materials and techniques were used and, therefore, reported upon in the current review. Zenith Alpha Thoracic Endovascular Graft was the most representative (24% of cases). Custom made, off-the-shelf, physician modified and in situ fenestrated endografts were also used in 39%, 22.4%, 18.6% and 18.9% of cases, respectively. Bridge stents were implanted in the 50.5% of cases. Technical success rate was 96%. The main intraoperative complication was the endoleak (5.2%) followed by stroke (4.8%). The in-hospital mortality was 2.5%. The mean follow-up was 18.5 months. The mortality related to the main operation during follow-up was 3.2% and not directly related to the main operation was 11.3%. During the follow-up, 92 cases (13.3%) in total had to undergo through a reintervention, 46.7% with endovascular repair and 26.1% with open surgical repair (the rest were not specified). Conclusion published experience with bEVAR and fEVAR in the aortic arch showed acceptable short-term effectiveness and safety. More well-conducted prospective clinical studies with long term follow-up, combined with comparative meta-analysis, are needed to elucidate the real benefit of those endovascular techniques in the aortic arch pathology.