bluuebunny/crossref_metadata_2025_split huggingface dataset:
Limitations in Helicopter Design
Authors: Bennett J. A. J. 
Published: October 2023

Ladies and Gentlemen,As most of you know this is the Fourth and last lecture of our present session, the other three having been given by Gp/Capt. LIPTROT, Mr. C. G. PULLIN and Mr. R. A. C. BRIE, covering an historical survey, design and operation of helicopters, etc., and to-day our lecturer is discussing “Limitations in Helicopter Design.”It gives me very great pleasure to introduce Dr. BENNETT to you, for I have known him personally for fifteen years or more, during the whole of which time he has been intimately associated with rotary wing and helicopter design.For some years prior to the war, Dr. BENNETT was with Messrs. G. & J. Weir and the Cierva Autogiro Co.; and during the war was C.T.O. at the Airborne Forces Experimental Establishment and spent two years in the U.S.A. where he latterly was attached to Wright Field as project engineer on helicopter research.
Sites for Rotor Stations—Some Town Planning Considerations
Authors: Littler F H 
Published: October 2023

The previous speaker has briefly stated the requirements which for satisfactory operation of a helicopter service should govern the siting of a Rotor Station they may be summarised as—commercially “a central location in the town, with convenient access by road and rail”, and—operationally “relative freedom from local ‘smog’ and from high obstructions”It is probable that the travelling public also would describe their chief requirement as “a central location and convenient road and rail access”, but when the question of siting is viewed disinterestedly—as it must be by the town planning authority—when account is taken of the probable effect that the Rotor Station, its use and its situation, may have upon the public in general, and on the owners and occupiers of adjacent property in particular—a rather different set of criteria must be considered
Military Aspects of the Transport Helicopter
Authors: Piasecki F N 
Published: October 2023

For the second occasion during the 1951/52 session of lectures, this Association has been honoured by the presence of an eminent member of the United States aircraft industry, since this evening we have Mr FRANK PIASECKI as our lecturerYou all know Mr PIASECKI very well by name In 1940 he founded an engineering group known as the P V Engineering Forum This later became the Piasecki Helicopter Corporation, and today he is Chairman of the Board of Directors In 1943 the first single rotor helicopter designed by that small band of people emerged, it was the PV2, and was flown successfully by Mr PIASECKI himself Quick to appreciate the military possibilities of a helicopter capable of carrying a large load and with ample cabin space, he initiated and led the development of the big PV-3 tandemrotor helicopter, and the United States Navy, recognising the merits of the design, awarded a contract for the supply of a quantity of machines of this type
Helicopter Research: a review of outstanding problems together with an account of some recent work at A & A A E
Authors: O'Hara F 
Published: October 2023

SummaryIn the first part of the paper a brief review is made of major items for research in the helicopter field, the subjects touched on including rotor aerodynamics, stability and control, evaluation of configurations, vibrations and fatigue, and operational aspects An outline is given, in the section on stability and control, of work being done at A & A E E in connection with the assessment of the longitudinal handling characteristics of helicopters The second part of the paper contains an account of recent work at A & A E E on the low speed and take-off performance of a helicopter An empirical method of low speed performance estimation is described, and the variation with wind speed of the ground effect on a rotor is discussed theoretically and on the basis of experimental results A theoretical analysis of the forward take-off motion of a helicopter is briefly presented, and the final section is concerned with the performance of a multi-engine helicopter in the event of failure of one engine, with particular reference to the possibility of safe operation from the type of site proposed for civil use
An Analysis of Present-Day Helicopter Maintenance
Authors: Swain F. L. 
Published: October 2023

In preparing this paper it was obvious to the writer, from a perusal of the titles of the other papers arranged for this meeting, that some of the subjects discussed will have been dealt with in some measure by previous speakers, as this paper also deals with the Westland-Sikorsky S-51 helicopter. Where such repetition occurs the writer tenders his apologies.The Westland Sikorsky helicopter is well known in this country through its commercial activities over the past three years, and more recently its application to the Navy and R.A.F., whilst its American opposite, the Sikorsky S-51, has accumulated many thousands of flying hours to its credit, proving that the design has dependability and adaptability for the many roles of operation it has to meet. A close liaison between the American and British makers ensures the best possible service to all its operators.The Westland-Sikorsky S-51 inherits to a large degree the same qualities as the American model, and in discussing its maintenance many of the practices used are common to both models.
Conduit Processes at the Haukadalur Geyser‐Hosting Hydrothermal Field (Iceland) Revealed by In Situ Temperature and High‐Speed Camera Measurements
Authors: Collignon Marine , Pioli Laura , Trippanera Daniele , Carrier Aurore , Lupi Matteo 
Published: October 2023

AbstractGeysers fascinate scientists and visitors for several centuries. However, many driving mechanisms such as heat transfer in the conduit and in the subsurface remain poorly understood. We document for the first time transient temperature variations inside the active Strokkur's and nearby quasi‐dormant Great Geysir's conduits, Iceland. While recording temperature inside the conduit, we visually monitored Strokkur's activity at the vent with a high‐speed camera, providing a high temporal resolution of the eruptions. Our results reveal heat transfer from a bubble trap to and through the conduit. We propose a model for the eruptive cycle of Strokkur that includes vapor slug rise, eruption, and conduit refill. Each water jet of an eruption is marked by an initial pulse of liquid water and vapor, emitted at a velocity between 5 and 28 m/s and generally followed by a second pulse less than a second later. The timing of eruptions coincides with temperature maxima in the conduit. After the eruption, the conduit is refilled by water falling back in the pool and drained from neighboring groundwater‐saturated geological units. This results in a temperature drop, the amplitude of which increases with depth while its period is reduced. This reflects faster heat transfer in the deeper than shallower part of the conduit. The amplitude of temperature drop following an eruption also increases with the eruption order, implying larger heat release by higher‐order eruptions. Temperature in the conduit subsequently increases until the next eruption, starting then a new cycle.
A Signature‐Based Hydrologic Efficiency Metric for Model Calibration and Evaluation in Gauged and Ungauged Catchments
Authors: Kiraz Melike , Coxon Gemma , Wagener Thorsten 
Published: October 2023

AbstractRainfall‐runoff models are commonly evaluated against statistical evaluation metrics. However, these metrics do not provide much insight into what is hydrologically wrong if a model fails to simulate observed streamflow well and they are also not applicable for ungauged catchments. Here, we propose a signature‐based hydrologic efficiency (SHE) metric by replacing the statistical components of current efficiency metrics with hydrologic signatures that can be regionalized for model evaluation in ungauged catchments. We test our new efficiency metric across 633 catchments from Great Britain. Strong correlations with Spearman rank and Pearson correlation values around 0.8 are found between our proposed metric and commonly used statistical evaluation metrics (NSE, KGE, and NP) demonstrating that the proposed SHE metric is related to existing metrics as much as these metrics are related to each other. For ungauged catchments, we regionalize the three signatures included in SHE and find that 78% of catchments have an absolute difference of SHE values between gauged and ungauged cases of less than 0.2. This difference varies depending on the quality of the regionalized bias and variance signature values. It means that the SHE metric is applicable for model evaluation in ungauged catchments if its signatures can be regionalized well. When applying the SHE metric in other domains with different hydrologic properties, modellers should carefully consider the components of the proposed metric with signatures best suited to their research domains and their regionalization potential.
A new approach to quantify visceral fat via bioelectrical impedance analysis and ultrasound compared to MRI
Authors: Hoffmann Jana , Thiele Jens , Kwast Stefan , Borger Michael Andrew , Schröter Thomas , Schmidt Jochen , Busse Martin 
Published: October 2023

Abstract
Background
Visceral adipose tissue (VAT) has been linked to systemic proinflammatory characteristics, and measuring it accurately usually requires sophisticated instruments. This study aimed to estimate VAT applying a simpler method that uses total subcutaneous fat and total body fat (BF) measurements.

Method
As part of our experimental approach, the subcutaneous fat mass (SFT) was measured via US (SFTtotal), and VAT was quantified by assessing MRI data. Both parameters were added to obtain total body fat (BFcalc). Those results were then compared to values obtained from a bioelectrical impedance analysis (BFBIA). Multiple regression analyses were employed to develop a simplified sex-specific equation for SFT, which was subsequently used in conjunction with BFBIA to determine VAT (VATEq).

Result
We observed excellent reliability between BFBIA and BFcalc, with no significant difference in body fat values (20.98 ± 8.36 kg vs. 21.08 ± 8.81 kg, p = 0.798, ICC 0.948). VATEq_female/male revealed excellent reliability when compared to VATMRI, and no significant difference appeared (women: 0.03 ± 0.66 kg with a 95% CI ranging from −1.26 kg to 1.32 kg, p = 0.815, ICC: 0.955.; men: −0.01 ± 0.85 kg with a 95% CI ranging from −1.69 kg to 1.66 kg, p = 0.925, ICC: 0.952).

Conclusion
Taking an experimental approach, VAT can be determined without MRI.
SET-PP2A complex as a new therapeutic target in KMT2A (MLL) rearranged AML
Authors: Di Mambro Antonella , Arroyo-Berdugo Yoana , Fioretti Tiziana , Randles Michael , Cozzuto Luca , Rajeeve Vinothini , Cevenini Armando , Austin Michael J. , Esposito Gabriella , Ponomarenko Julia , Lucas Claire M. , Cutillas Pedro , Gribben John , Williams Owen , Calle Yolanda , Patel Bela , Esposito Maria Teresa 
Published: October 2023

AbstractKMT2A-rearranged (KMT2A-R) is an aggressive and chemo-refractory acute leukemia which mostly affects children. Transcriptomics-based characterization and chemical interrogation identified kinases as key drivers of survival and drug resistance in KMT2A-R leukemia. In contrast, the contribution and regulation of phosphatases is unknown. In this study we uncover the essential role and underlying mechanisms of SET, the endogenous inhibitor of Ser/Thr phosphatase PP2A, in KMT2A-R-leukemia. Investigation of SET expression in acute myeloid leukemia (AML) samples demonstrated that SET is overexpressed, and elevated expression of SET is correlated with poor prognosis and with the expression of MEIS and HOXA genes in AML patients. Silencing SET specifically abolished the clonogenic ability of KMT2A-R leukemic cells and the transcription of KMT2A targets genes HOXA9 and HOXA10. Subsequent mechanistic investigations showed that SET interacts with both KMT2A wild type and fusion proteins, and it is recruited to the HOXA10 promoter. Pharmacological inhibition of SET by FTY720 disrupted SET-PP2A interaction leading to cell cycle arrest and increased sensitivity to chemotherapy in KMT2A-R-leukemic models. Phospho-proteomic analyses revealed that FTY720 reduced the activity of kinases regulated by PP2A, including ERK1, GSK3β, AURB and PLK1 and led to suppression of MYC, supporting the hypothesis of a feedback loop among PP2A, AURB, PLK1, MYC, and SET. Our findings illustrate that SET is a novel player in KMT2A-R leukemia and they provide evidence that SET antagonism could serve as a novel strategy to treat this aggressive leukemia.
Amino acid auxotrophies in human gut bacteria are linked to higher microbiome diversity and long-term stability
Authors: Starke Svenja , Harris Danielle M M , Zimmermann Johannes , Schuchardt Sven , Oumari Mhmd , Frank Derk , Bang Corinna , Rosenstiel Philip , Schreiber Stefan , Frey Norbert , Franke Andre , Aden Konrad , Waschina Silvio 
Published: October 2023

AbstractAmino acid auxotrophies are prevalent among bacteria. They can govern ecological dynamics in microbial communities and indicate metabolic cross-feeding interactions among coexisting genotypes. Despite the ecological importance of auxotrophies, their distribution and impact on the diversity and function of the human gut microbiome remain poorly understood. This study performed the first systematic analysis of the distribution of amino acid auxotrophies in the human gut microbiome using a combined metabolomic, metagenomic, and metabolic modeling approach. Results showed that amino acid auxotrophies are ubiquitous in the colon microbiome, with tryptophan auxotrophy being the most common. Auxotrophy frequencies were higher for those amino acids that are also essential to the human host. Moreover, a higher overall abundance of auxotrophies was associated with greater microbiome diversity and stability, and the distribution of auxotrophs was found to be related to the human host’s metabolome, including trimethylamine oxide, small aromatic acids, and secondary bile acids. Thus, our results suggest that amino acid auxotrophies are important factors contributing to microbiome ecology and host-microbiome metabolic interactions.
Chronic administration of XBD173 ameliorates cognitive deficits and neuropathology via 18 kDa translocator protein (TSPO) in a mouse model of Alzheimer’s disease
Authors: Pradhan Arpit Kumar , Neumüller Tatjana , Klug Claudia , Fuchs Severin , Schlegel Martin , Ballmann Markus , Tartler Katharina Johanna , Pianos Antoine , Garcia Maria Sanchez , Liere Philippe , Schumacher Michael , Kreuzer Matthias , Rupprecht Rainer , Rammes Gerhard 
Published: October 2023

AbstractAlzheimer’s disease (AD) is characterized by the accumulation of β-amyloid peptide (Aβ). It affects cognition and leads to memory impairment. The mitochondrial translocator protein (TSPO) plays an essential role in maintaining mitochondrial homeostasis and has been implicated in several neuronal disorders or neuronal injuries. Ligands targeting the mitochondrial translocator protein (18 kDa), promote neurosteroidogenesis and may be neuroprotective. To study whether the TSPO ligand XBD173 may exert early neuroprotective effects in AD pathology we investigated the impact of XBD173 on amyloid toxicity and neuroplasticity in mouse models of AD. We show that XBD173 (emapunil), via neurosteroid-mediated signaling and delta subunit-containing GABAA receptors, prevents the neurotoxic effect of Aβ on long-term potentiation (CA1-LTP) in the hippocampus and prevents the loss of spines. Chronic but not acute administration of XBD173 ameliorates spatial learning deficits in transgenic AD mice with arctic mutation (ArcAβ). The heterozygous TSPO-knockout crossed with the transgenic arctic mutation model of AD mice (het TSPOKO X ArcAβ) treated with XBD173 does not show this improvement in spatial learning suggesting TSPO is needed for procognitive effects of XBD173. The neuroprotective profile of XBD173 in AD pathology is further supported by a reduction in plaques and soluble Aβ levels in the cortex, increased synthesis of neurosteroids, rescued spine density, reduction of complement protein C1q deposits, and reduced astrocytic phagocytosis of functional synapses both in the hippocampus and cortex. Our findings suggest that XBD173 may exert therapeutic effects via TSPO in a mouse model of AD.
Restoratively driven planning for implants in the posterior maxilla - Part 1: alveolar bone healing, bone assessment and clinical classifications
Authors: M. King Elizabeth , Schofield Jonathon 
Published: October 2023

AbstractSinus augmentation in conjunction with implant placement is widely considered to be a predictable and successful treatment option for the edentulous posterior maxilla. However, the anatomical changes of the posterior maxilla following tooth extraction (namely alveolar atrophy and pneumatisation of the maxillary sinus) creates unique challenges for implant and prosthodontic rehabilitation. A large volume of literature has been published regarding the surgical indications and treatment planning for implants in the posterior maxilla. In comparison, there is a relative paucity of literature regarding the prosthodontic challenges associated with implants placed in augmented maxillary sinuses. This article describes the scientific background of native and grafted alveolar bone healing in relation to implant rehabilitation. Furthermore, clinical classifications available to assist implant treatment planning are described.
Body composition and cancer survival: a narrative review
Authors: Bradshaw Patrick T. 
Published: October 2023

AbstractInterest in understanding the relationship between body composition and cancer survival has remained strong for decades, with a number of recent systematic reviews on the topic. However, the current state of evidence is based on heterogeneous exposure definitions based on anthropometry, yielding inconsistent findings with regard to this association. Recently the field has taken an exciting direction with the application of radiological assessments to measure specific aspects of body composition, yet reconciliation of findings from these modern assessment tools with those from the historic use of anthropometric data proves challenging. In this paper, I briefly review the biological basis for a link between body composition and cancer survival and summarize the epidemiological evidence with consideration to specific exposure measures. As enthusiasm is building around novel assessments, I conclude with a discussion of issues that researchers should be aware of when interpreting results from these new modalities.
The puzzle of plant hybridisation: a high propensity to hybridise but few hybrid zones reported
Authors: Nieto Feliner Gonzalo , Criado Ruiz David , Álvarez Inés , Villa-Machío Irene 
Published: October 2023

AbstractAn interesting conundrum was recently revealed by R. Abbott when he found that the number of hybrid zones reported in the literature for plants is very low, given the propensity of plants to hybridise. In another literature survey on hybrid zones performed over the period 1970–2022, we found that the number of hybrid zones reported for vertebrates was 2.3 times greater than that reported for vascular plants, even though there are about six times more vascular plant species than vertebrates. Looking at the number of papers reporting hybrid zones, there are 4.9 times more on vertebrates than on vascular plants. These figures support the relevance of this conundrum. In this paper we aim to shed light on this question by providing a structured discussion of the causes that may underlie this conundrum. We propose six non-mutually exclusive factors, namely lack or deficit of spatial structure, lack or deficit of genetic structure, effects of hybridisation between non-closely related species, lability of plant hybrid zones over time, botanists’ perception of hybridisation, and deficit of population genetic data. There does not appear to be a single factor that explains our puzzle, which applies to all cases of plants where hybridisation is detected but no hybrid zone is reported. It is argued that some plant features suggest that the puzzle is not, at least entirely, due to insufficient knowledge of the specific cases, a hypothesis that should be addressed with a wider range of empirical data across different taxonomic groups.
Multivalent Tau/PSD-95 interactions arrest in vitro condensates and clusters mimicking the postsynaptic density
Authors: Shen Zheng , Sun Daxiao , Savastano Adriana , Varga Sára Joana , Cima-Omori Maria-Sol , Becker Stefan , Honigmann Alf , Zweckstetter Markus 
Published: October 2023

AbstractAlzheimer’s disease begins with mild memory loss and slowly destroys memory and thinking. Cognitive impairment in Alzheimer’s disease has been associated with the localization of the microtubule-associated protein Tau at the postsynapse. However, the correlation between Tau at the postsynapse and synaptic dysfunction remains unclear. Here, we show that Tau arrests liquid-like droplets formed by the four postsynaptic density proteins PSD-95, GKAP, Shank, Homer in solution, as well as NMDA (N-methyl-D-aspartate)-receptor-associated protein clusters on synthetic membranes. Tau-mediated condensate/cluster arrest critically depends on the binding of multiple interaction motifs of Tau to a canonical GMP-binding pocket in the guanylate kinase domain of PSD-95. We further reveal that competitive binding of a high-affinity phosphorylated peptide to PSD-95 rescues the diffusional dynamics of an NMDA truncated construct, which contains the last five amino acids of the NMDA receptor subunit NR2B fused to the C-terminus of the tetrameric GCN4 coiled-coil domain, in postsynaptic density-like condensates/clusters. Taken together, our findings propose a molecular mechanism where Tau modulates the dynamic properties of the postsynaptic density.
Continuous electroproduction of formate via CO2 reduction on local symmetry-broken single-atom catalysts
Authors: Dong Juncai , Liu Yangyang , Pei Jiajing , Li Haijing , Ji Shufang , Shi Lei , Zhang Yaning , Li Can , Tang Cheng , Liao Jiangwen , Xu Shiqing , Zhang Huabin , Li Qi , Zhao Shenlong 
Published: October 2023

AbstractAtomic-level coordination engineering is an efficient strategy for tuning the catalytic performance of single-atom catalysts (SACs). However, their rational design has so far been plagued by the lack of a universal correlation between the coordination symmetry and catalytic properties. Herein, we synthesised planar-symmetry-broken CuN3 (PSB-CuN3) SACs through microwave heating for electrocatalytic CO2 reduction. Remarkably, the as-prepared catalysts exhibited a selectivity of 94.3% towards formate at −0.73 V vs. RHE, surpassing the symmetrical CuN4 catalyst (72.4% at −0.93 V vs. RHE). In a flow cell equipped with a PSB-CuN3 electrode, over 90% formate selectivity was maintained at an average current density of 94.4 mA cm−2 during 100 h operation. By combining definitive structural identification with operando X-ray spectroscopy and theoretical calculations, we revealed that the intrinsic local symmetry breaking from planar D4h configuration induces an unconventional dsp hybridisation, and thus a strong correlation between the catalytic activity and microenvironment of metal centre (i.e., coordination number and distortion), with high preference for formate production in CuN3 moiety. The finding opens an avenue for designing efficient SACs with specific local symmetries for selective electrocatalysis.