Systematic Series Research Articles

Numerical Investigation of Single and Double Steps in Planing Hulls

Incorporating steps into a hull reduces the wetted surface, promoting improved hydrodynamic lift and reduced resistance at high speeds, provided that the step is designed appropriately. Traditional hydrodynamics studies rely on scaled model testing in towing tanks, but numerical tools offer a more efficient alternative. This study focused on investigating the hydrodynamic performance of stepped hulls by modifying the parent hull of the Naples Systematic Series (C1). The Computational Fluid Dynamics (CFD) code SIEMENS PLM STAR CCM+ version 2302 was used for simulations, including four different beam Froude numbers (FrB = 1.13, 2.22, 2.56, and 2.96) and a total of 15 hull configurations with single and double steps. By employing a three-dimensional computational analysis of multiphase flow using Dynamic Fluid–Body Interaction (DFBI) and overset mesh, various performance parameters such as resistance coefficient, dimensionless wetted surface, sinkage, and dynamic trim were analyzed. The accuracy of the CFD results was confirmed through comparison with experimental data and grid uncertainty assessment. The study demonstrated that placing a single step near the transom decreased trim and increased resistance and wetted surface. Conversely, positioning a step in the forward section reduced the trim angle at lower step heights but increased trim at higher step heights in single-stepped hulls. The application of these findings contributes to the design optimization of stepped hulls for enhanced performance in high-speed maritime applications.

Charge-Selective Photocatalytic Degradation of Organic Dyes Driven by Naturally Occurring Halloysite Nanotubes

This study explores the use of Halloysite NanoTubes (HNTs) as photocatalysts capable of decomposing organic dyes under exposure to visible or ultraviolet light. Through a systematic series of photocatalytic experiments, we unveil that the photodegradation of Rhodamine B, used as a model cationic dye, is significantly accelerated in the presence of HNTs. We observe that the extent of RhB photocatalytic degradation in 100 min in the presence of the HNTs is ~four times higher compared to that of bare RhB. Moreover, under optimized conditions, the as-extracted photodegradation rate of RhB (~0.0022 min−1) is comparable to that of the previously reported work on the photodegradation of RhB in the presence of tubular nanostructures. A parallel effect is observed for anionic Coumarin photodegradation, albeit less efficiently. Our analysis attributes this discrepancy to the distinct charge states of the two dyes, influencing their attachment sites on HNTs. Cationic Rhodamine B molecules preferentially attach to the outer surface of HNTs, while anionic Coumarin molecules tend to attach to the inner surface. By leveraging the unique properties of HNTs, a family of naturally occurring nanotube structures, this research offers valuable insights for optimizing photocatalytic systems in the pursuit of effective and eco-friendly solutions for environmental remediation.

Aggregation-Induced Emission of Naphthalene Diimides: Effect of Chain Length on Liquid and Solid-Phase Emissive Properties.

The aggregation-induced emission (AIE) properties of a systematic series of naphthalene diimides (NDIs) varying the chain length at the imide positions have been studied. A solvophobic collapse of NDI units through the flash injection of THF NDI solutions in sonicating water triggers the formation of stable suspensions with enhanced fluorescence emissions. Shorter chains favor the π-π stacking of NDI units through H-aggregation producing a strong AIE effect showing remarkably high quantum yields that have not been observed for non core-substitued NDIs previously. On the other hand, NDIs functionalized with longer chains lead to more disordered domains where π-π stacking between NDI units is mainly given by J-aggregation unfavoring the AIE effect.

Backside versus Frontside SN2 Reactions of Alkyl Triflates and Alcohols.

Nucleophilic substitution reactions are elementary reactions in organic chemistry that are used in many synthetic routes. By quantum chemical methods, we have investigated the intrinsic competition between the backside SN2 (SN2-b) and frontside SN2 (SN2-f) pathways using a set of simple alkyl triflates as the electrophile in combination with a systematic series of phenols and partially fluorinated ethanol nucleophiles. It is revealed how and why the well-established mechanistic preference for the SN2-b pathway slowly erodes and can even be overruled by the unusual SN2-f substitution mechanism going from strong to weak alcohol nucleophiles. Activation strain analyses disclose that the SN2-b pathway is favored for strong alcohol nucleophiles because of the well-known intrinsically more efficient approach to the electrophile resulting in a more stabilizing nucleophile-electrophile interaction. In contrast, the preference of weaker alcohol nucleophiles shifts to the SN2-f pathway, benefiting from a stabilizing hydrogen bond interaction between the incoming alcohol and the leaving group. This hydrogen bond interaction is strengthened by the increased acidity of the weaker alcohol nucleophiles, thereby steering the mechanistic preference toward the frontside SN2 pathway.

A novel staging system to consolidate silent sinus syndrome and chronic maxillary atelectasis: A systematic review and case series.

Silent sinus syndrome (SSS) and chronic maxillary atelectasis (CMA) represent an overlapping clinical entity, both likely lying on the spectrum of one disease process. There is widespread inconsistency of diagnosis in the literature of reported cases of SSS and CMA. We propose a novel, comprehensive staging system to simplify diagnosis and inform management.

Preventable suicides involving medicines: A systematic case series of coroners’ reports in England and Wales

BackgroundIn England and Wales coroners have a duty to write a report, called a Prevention of Future Deaths report or PFD, when they believe that actions should be taken to prevent future deaths. Coroners send PFDs to individuals and organisations who are required to respond within 56 days. Despite the increase in mental health concerns and growing use of medicines, deaths reported by coroners that have involved medicine-related suicides had not yet been explored. Therefore, this study aimed to systematically assess coroners’ PFD reports involving suicides in which a medicine caused or contributed to the death to identify lessons for suicide prevention. MethodsUsing the Preventable Deaths Tracker database, 3037 coroners' PFD reports in England and Wales were screened for eligibility between July 2013 and December 2019. Reports were included if they involved suicide or intentional self-harm and prescribed or over-the-counter medication; illicit drugs were excluded. Following data extraction, descriptive statistics, document and content analysis were performed to assess coroners’ concerns and the recipients of reports. ResultsThere were 734 suicide-related coroner reports, with 100 (14%) reporting a medicine. Opioids (40%) were the most common class involved, followed by antidepressants (30%). There was wide geographical variation in the writing of reports; coroners in Manchester wrote the most (18%). Coroners expressed 237 concerns; the most common were procedural inadequacies (14%, n = 32), inadequate documentation and communication (10%, n = 22), and inappropriate prescription access (9%, n = 21). 203 recipients received the PFDs, with most sent to NHS trusts (31%), clinical commissioning groups (10%), and general practices (10%), of which only 58% responded to the coroner. ConclusionsOne in four coroner reports in England and Wales involved suicides, with one in seven suicide-related deaths involving a medicine. Concerns raised by coroners highlighted gaps in care that require action from the Government, health services, and prescribers to aid suicide prevention. Coroner reports should be routinely used and monitored to inform public health policy, disseminated nationally, and responses to coroners should be transparently enforced so that actions are taken to prevent future suicides.

Adverse events associated with the delivery of telerehabilitation: A scoping review protocol.

This scoping review aims to map the existing research on adverse events during the delivery of telerehabilitation. Telerehabilitation, a subset of telemedicine, has gained traction during the COVID-19 pandemic as a means to deliver rehabilitation services remotely. However, there exists a research gap as there has yet to be any scoping review, systematic review, or meta-analysis published to identify and summarize the current primary research on adverse events related to telerehabilitation as a whole. It is important to understand how adverse events, such as falls during physiotherapy or aspiration pneumonia during speech language pathology sessions, are associated with telerehabilitation delivery. This will help to identify key limitations for optimizing telerehabilitation delivery by allowing for the development of key risk-mitigation measures and quality indicators. It can also help improve the uptake of telerehabilitation among clinicians and patients. This review aims to fill this research gap by conducting a search of published literature on adverse events in telerehabilitation. Anticipated key findings of this scoping review include identifying the characteristics and frequencies of adverse events during telerehabilitation, the patient populations and types of telerehabilitation associated with the most adverse events, and the quality of reporting of adverse events. The review follows the Joanna Briggs Institute (JBI) methodological framework and adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines. The review protocol has been registered and published on Open Science Framework. A comprehensive search strategy was implemented across multiple databases (MEDLINE ALL, EMBASE, APA PsycINFO, CENTRAL, and CINAHL). All stages (screening, extraction, and synthesis) will be conducted in duplicate and independently, with data extraction following the TIDieR framework, along with authors, year of publication (before or after COVID), population and sample size, and specific mode/s of telerehabilitation delivery. For synthesis, data will be summarized quantitatively using numerical counts and qualitatively via content analysis. The data will be grouped by intervention type and by type of adverse event. This scoping review will include qualitative and quantitative studies published between 2013 and 2023, written in English, and conducted in any geographic area. All modes of telerehabilitation delivery (asynchronous, synchronous, or hybrid) will be included. Systematic reviews, meta-analyses, commentaries, protocols, opinion pieces, conference abstracts, and case series with fewer than five participants will be excluded.

A linearly decreasing deterministic annealing algorithm for the multi-vehicle dial-a-ride problem.

Dial a ride problem (DARP) is a complex version of the pick-up and delivery problem with many practical applications in the field of transportation. This study proposes an enhanced deterministic annealing algorithm for the solution of large-scale multi-vehicle DARPs. The proposed method always explores the feasible search space; therefore, a feasible solution is guaranteed at any point of termination. This method utilises advanced local search operators to accelerate the search for optimal solutions and it relies on a linearly decreasing deterministic annealing schedule to limit poor jumps during the course of search. This study puts forward a systematic series of experiments to compare the performance of solution methods from various angles. The proposed method is compared with the most efficient methods reported in the literature i.e., the Adaptive Large Neighbourhood Search (ALNS), Evolutionary Local Search (ELS), and Deterministic Annealing (DA) using standard benchmarks. The results suggest that the proposed algorithm is on average faster than the state-of-the-art algorithms in reaching competitive objective values across the range of benchmarks.

Utilizing Machine Learning Tools for Calm Water Resistance Prediction and Design Optimization of a Fast Catamaran Ferry

The article aims to design a calm water resistance predictor based on Machine Learning (ML) Tools and develop a systematic series for battery-driven catamaran hullforms. Additionally, employing a machine learning predictor for design optimization through the utilization of a Genetic Algorithm (GA) in an expedited manner. Regression Trees (RTs), Support Vector Machines (SVMs), and Artificial Neural Network (ANN) regression models are applied for dataset training. A hullform optimization was implemented for various catamarans, including dimensional and hull coefficient parameters based on resistance, structural weight reduction, and battery performance improvement. Design distribution based on Lackenby transformation fulfills all of the design space, and sequentially, a novel self-blending method reconstructs new hullforms based on two parents blending. Finally, a machine learning approach was conducted on the generated data of the case study. This study shows that the ANN algorithm correlates well with the measured resistance. Accordingly, by choosing any new design based on owner requirements, GA optimization obtained the final optimum design by using an ML fast resistance calculator. The optimization process was conducted on a 40 m passenger catamaran case study that achieved a 9.5% cost function improvement. Results show that incorporating the ML tool into the GA optimization process accelerates the ship design process.

Non-statistical assembly of multicomponent [Pd2ABCD] cages.

Self-assembled hosts, inspired by biological receptors and catalysts, show application potential in sustainable synthesis, energy conversion and medicine. Implementing multiple functionalities in the form of distinguishable building blocks, however, is difficult without risking narcissistic self-sorting or a statistical mess. Here we report a systematic series of integratively self-assembled heteroleptic cages in which two square-planar PdII cations are bridged by four different bis-pyridyl ligands, A, B, C and D, via synergistic effects to exclusively form a single isomer-the lantern-shaped cage [Pd2ABCD]. This self-sorting goal-forming just one out of 55 possible structures-is reached under full thermodynamic control and can be realized progressively (by combining progenitors, such as [Pd2A2C2] with [Pd2B2D2]), directly from ligands and PdII cations or by mixing all four corresponding homoleptic cages. The rational design of complex multicomponent assemblies that enables the modular incorporation of diverse chemical moieties will advance their applicability in functional nanosystems.

Confined Lewis Pairs: Investigation of the X- →Si20 Interaction in Halogen-Encapsulating Silafulleranes.

A joint theoretical and experimental study on 32 endohedral silafullerane derivatives [X@Si20 Y20 ]- (X=F-I; Y=F-I, H, Me, Et) and -[Cl@Si20 H12 Y8 ]- (Y=F-I) is presented. First, we evaluated the structure-determining template effect of Cl- in a systematic series of concave silapolyquinane model systems. Second, we investigated the X- →Si20 interaction energy ( ) as a function of X- and Y and found the largest values for electron-withdrawing exohedral substituents Y. Given that X- ions can be considered as Lewis bases and empty Si20 Y20 clusters as Lewis acids, we classify our inseparable host-guest complexes [X@Si20 Y20 ]- as "confined Lewis pairs". Third, 35 Cl NMR spectroscopy proved to be highly diagnostic for an experimental assessment of the Cl- →Si20 interaction as the paramagnetic shielding and, in turn, (35 Cl) of the endohedral Cl- ion correlate inversely with . Finally, we disclose the synthesis of [PPN][Cl@Si20 Y20 ] (Y=Me, Et, Br) and provide a thorough characterization of these new silafulleranes.

Confined Lewis Pairs: Investigation of the X−→Si20 Interaction in Halogen‐Encapsulating Silafulleranes

AbstractA joint theoretical and experimental study on 32 endohedral silafullerane derivatives [X@Si20Y20]− (X=F‐I; Y=F‐I, H, Me, Et) and ‐[Cl@Si20H12Y8]− (Y=F‐I) is presented. First, we evaluated the structure‐determining template effect of Cl− in a systematic series of concave silapolyquinane model systems. Second, we investigated the X−→Si20 interaction energy ( ) as a function of X− and Y and found the largest values for electron‐withdrawing exohedral substituents Y. Given that X− ions can be considered as Lewis bases and empty Si20Y20 clusters as Lewis acids, we classify our inseparable host–guest complexes [X@Si20Y20]− as “confined Lewis pairs”. Third, 35Cl NMR spectroscopy proved to be highly diagnostic for an experimental assessment of the Cl−→Si20 interaction as the paramagnetic shielding and, in turn, (35Cl) of the endohedral Cl− ion correlate inversely with . Finally, we disclose the synthesis of [PPN][Cl@Si20Y20] (Y=Me, Et, Br) and provide a thorough characterization of these new silafulleranes.

Chemical bonding effects in Sc compounds studied using X-ray absorption and X-ray photoelectron spectroscopies.

Advances on understanding the nature of the chemical bonding and electron correlation effects during the X-ray absorption process in ionic-covalent metal complexes has been achieved for most of the transition elements, except for scandium, due to the lack of a systematic series of spectroscopic reference spectra and the shortage of standard crystallographic data on scandium compounds. To close the gap, the chemical bonding effects in eight Sc compounds are studied using X-ray absorption spectroscopy (XAS) at Sc K and L2,3 absorption edges and X-ray photoelectron spectroscopy (XPS). Indeed, the fine structure of the XAS Sc K edge reflects the chemical sp3-like bond formed between scandium and the ligand while the L2,3 edge and the pre-edge features of the K-edge provide a direct insight into the crystal field parameters at the Sc site in the coordination compound. The XPS data provide the information on binding energies of the core electrons involved in the electron transitions caused by the absorption of high energy X-rays. XAS and XPS complement each other by accessing the information on Sc structure on bulk and the surface. Herein, comprehensive information on the electronic structure of well-known crystalline materials based on Sc is given with spectroscopic fingerprints X-ray data. This will help to predict the formation of chemical bonds in the unknown components via the systematic evaluation of the available spectroscopic fingerprints.

A linguistic cycle for speech orienters

Abstract This paper describes the way in which represented speech is introduced in ten eastern Bantu languages, and explains the different constructions used as stages of a linguistic cycle. In this cycle, verbs of speech develop into quotative markers, and eventually cease to be used to introduce direct speech. This cycle can be understood as a systematic and unidirectional series of constructional changes.

Supported Iridium Catalysts for Water Electrolysers

It is essential to reduce iridium in water electrolysers without compromising performance to lower the cost of green hydrogen. One strategy often used in catalysis to reduce precious metal catalyst usage is to deposit catalysts on high surface area supports. However, the catalyst supports need to be stable under the reaction conditions and also economically viable. Additionally, the catalyst-support moieties need to be sufficiently conductive. In this project, we explore platinum coated titanium dioxide as supports for iridium catalysts. Platinum is necessary to improve conductivity of the support motifs. Without this conductive platinum layer, extremely high (75 wt%) iridium loadings are needed to prepare commercially viable supported iridium catalysts.1, 2 In this work we synthesise and characterise a systematic series of catalysts whereby the Pt loading is varied in order to understand the loading effect on conductivity, and thus, electrocatalytic activities and durabilities.Previously, we have demonstrated the efficacy of a Pt conductive layer as an effective strategy for boosting the mass activity of Iridium in a half-cell configuration.4 However, translating the performance, more critically durability, in a device remained to be demonstrated. Here, we also begin by rapidly assessing the electrochemical performance of the library of prepared catalysts in a half-cell configuration (rotating disk electrodes, RDEs). Subsequently, catalysts that show promising activity and durability in half-cell are integrated into a PEM electrolyser. This approach is economic and efficient since integrating catalysts into membrane electrode assemblies and running electrolyser tests are resource and time intensive. However, there are challenges associated with replicating activity and durability from half-cell to device performance.3 Thus, we also explore methodologies and strategies to optimise our half-cell investigations to mimic full device conditions more closely. We have demonstrated that our strategy to engineer iridium catalysts has led to greater than 50% reduction in iridium content necessary in water electrolysers. And yet, our devices show performance and durability comparable to state-of-the-art technology.In this presentation we will discuss remaining challenges for hydrogen production using proton exchange membrane water electrolysers. We will also present materials characterisations and electrochemical performance of our catalysts in half-cell and full device configuration.Reference: K. Ayers, N. Danilovic, R. Ouimet, M. Carmo, B. Pivovar and M. Bornstein, Annu Rev Chem Biomol Eng, 2019, 10, 219-239. M. Bernt, A. Hartig‐Weiß, M. F. Tovini, H. A. El‐Sayed, C. Schramm, J. Schröter, C. Gebauer and H. A. Gasteiger, Chemie Ingenieur Technik, 2020, 92, 31-39. T. Lazaridis, B. M. Stühmeier, H. A. Gasteiger and H. A. El-Sayed, Nature Catalysis, 2022, 5, 363-373. Y. N. Regmi, E. Tzanetopoulos, G. Zeng, X. Peng, D. I. Kushner, T. A. Kistler, L. A. King and N. Danilovic, ACS Catalysis, 2020, 10, 13125-13135.

Preventable deaths involving sepsis in England and Wales, 2013–2022: a systematic case series of coroners’ reports

Preventable deaths involving sepsis in England and Wales, 2013–2022: a systematic case series of coroners’ reports

Blastic Plasmocytoid Dendritic Cell Neoplasm (BPDCN): Clinical Features and Histopathology with a Therapeutic Overview.

Blastic Plasmacytoid Dendritic Cell Neoplasms (BPDCNs) are a rare, highly aggressive hematological malignant neoplasm that primarily involve the skin, bone marrow, lymph nodes and even extra-nodal sites. The rarity and relative poor description of cases in the literature make it necessary to review and further studies that deeply investigate this entity not only in a histopathological but also molecular field. In August-September 2023, we searched MEDLINE, PubMed and Scopus for randomized controlled trials (RCTs), narrative and systematic reviews, meta-analyses, observational studies (either longitudinal or retrospective), and case series published in English in the last 25 years using the keywords BPDCN, PDCs, Blastic NK-cell lymphoma, agranular CD4+ NK leukemia/lymphoma, agranular CD4+ CD56+ hematodermic neoplasm/tumor. Despite the progress made in recent years in the diagnosis and biological understanding of the disease, until 2018 there was no clear consensus regarding its treatment and the main therapeutic schemes used were based on chemotherapy regimens already used in the treatment of lymphomas, acute lymphoblastic leukemia (ALL) and/or acute myeloid leukemia (AML). In this narrative review, we address the definition and epidemiological features of BPDCN, provide the different theories on the etiopathogenesis with particular attention to the presumed cell of origin, discuss the main clinical manifestations that provide a sign of its presence, summarize the main histopathological and immunophenotypic characteristics with special attention to the most important markers, and finally, we provide some of the most effective information on the therapeutic treatment modalities of BPDCN.

Hyperammonemic Encephalopathy in Multiple Myeloma: Systematic Review and Case Series

Objectives: To better understand the presentation and clinical outcomes of hyperammonemic encephalopathy in multiple myeloma, we report 3 cases from our institution and present 55 published cases from the literature. Background/Intro: Hyperammonemia is a rare but life-threatening complication of multiple myeloma with poor survival despite treatment. Little is known about the clinical presentation and outcomes of patients suffering from this entity. We hereby report a systematic review and a meta-analysis of cases with hyperammonemic encephalopathy. Methods: Case reports and case series were identified using the Medline database, as well as PubMed search engine. Clinical and pathological data were collected and stratified by demographics and treatment. The data was further analyzed using SPSS. Results: A total of 58 patients were included in the study. The mean age of the affected patients was 64.4 years, male to female ratio was 1.15:1. The median ammonia level measured was 123 μmol/L. Stage III disease was most prevalent in reported cases (89%). Most common MM subtype was IgG (38%) followed by IgA (36%). Thirty-seven patients (64%) had relapsed disease, while 17 (29%) were new diagnoses. Overall, 35 out of 58 (60%) patients died while being treated as inpatients. Chemotherapy was the only variable associated with an improved survival with p-0.02. Conclusion: Hyperammonemia in the setting of multiple myeloma is an uncommon complication. It is associated with poor prognosis. Treatment should begin as soon as the diagnosis is confirmed with myeloma directed therapy in order to improve survival.

SPECT/CT and PET/CT for the Evaluation of Persistent or Recurrent Pain After Spine Surgery: A Systematic Review and Case Series

ObjectiveThe differential diagnosis for postoperative back pain is broad, and conventional imaging modalities are not always conclusive. Therefore, we performed a systematic review of the literature and present case studies describing the use of single-photon emission CT (SPECT)/CT or positron emission tomography (PET)/CT in the diagnosis of back pain following spine surgery. MethodsA systematic review was conducted according to PRISMA guidelines across 5databases. Relevant keywords included PET/CT, bone SPECT/CT, and pseudarthrosis. The studies were assessed for diagnostic accuracy of the imaging technologies. ResultsA total of 2444 studies were screened, 91 were selected for full-text review, and 21 were ultimately included. Six retrospective studies investigated the use of SPECT/CT with a total sample size of 309 patients. Two of these studies used SPECT/CT to predict screw loosening in over 50% of patients. Eight studies examined the use of 18-fluoride sodium fluoride (18F-NaF) PET/CT. Among these studies, measures of diagnostic accuracy varied but overall demonstrated the ability of 18F-NaF PET/CT to detect screw loosening and pseudarthrosis. Seven studies examined 18F-fluorodeoxyglucose (FDG) PET/CT and supported its utility in the diagnosis of postoperative infections in the spine. ConclusionsPET/CT and SPECT/CT are useful in the evaluation of postoperative pain of the spine, especially in patients for whom conventional imaging modalities yield inconclusive results. More diagnostic accuracy studies with strong reference standards are needed to compare hybrid imaging to conventional imaging.

The Influence of Lyophobicity and Lyophilicity of Film-Forming Systems on the Properties of Tin Oxide Films

In this work, the effects of lyophobicity and lyophilicity of film-forming systems on the properties of thin nanostructured films was studied. Systematic series of experiments were carried out with lyophilic film-forming systems: SnCl4/EtOH, SnCl4/EtOH/NH4F, SnCl4/EtOH/NH4OH and lyophobic systems: SnO2/EtOH and SnO2/EtOH/NH4F. Film growth mechanisms are determined depending on the type of film-forming system. The surface of the films was studied using a scanning electron microscope and an optical microscope. The spectrophotometric method is used to study the transmission spectra and the extinction coefficient. The surface resistance of the films was determined using the four-probe method. The quality factor and specific conductivity of the films are calculated. It was found that the addition of a fluorinating agent (NH4F) to a film-forming system containing SnO2 in the form of a dispersed phase does not lead to an increase in the specific conductivity of the films. X-ray diffraction analysis proved the incorporation of fluorine ions into the structure of the film obtained from the SnCl4/EtOH/NH4F system by the presence of SnOF2 peaks. In films obtained from SnO2/EtOH/NH4F systems, there are no SnOF2 peaks. In this case, ammonium fluoride crystallizes as a separate phase and decomposes into volatile compounds.