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1.
PLoS One ; 19(5): e0302793, 2024.
Article in English | MEDLINE | ID: mdl-38739601

ABSTRACT

BACKGROUND: In cardiology, cardiac output (CO) is an important parameter for assessing cardiac function. While invasive thermodilution procedures are the gold standard for CO assessment, transthoracic Doppler echocardiography (TTE) has become the established method for routine CO assessment in daily clinical practice. However, a demand persists for non-invasive approaches, including oscillometric pulse wave analysis (PWA), to enhance the accuracy of CO estimation, reduce complications associated with invasive procedures, and facilitate its application in non-intensive care settings. Here, we aimed to compare the TTE and oscillometric PWA algorithm Antares for a non-invasive estimation of CO. METHODS: Non-invasive CO data obtained by two-dimensional TTE were compared with those from an oscillometric blood pressure device (custo med GmbH, Ottobrunn, Germany) using the integrated algorithm Antares (Redwave Medical GmbH, Jena, Germany). In total, 59 patients undergoing elective cardiac catheterization for clinical reasons (71±10 years old, 76% males) were included. Agreement between both CO measures were assessed by Bland-Altman analysis, Student's t-test, and Pearson correlations. RESULTS: The mean difference in CO was 0.04 ± 1.03 l/min (95% confidence interval for the mean difference: -0.23 to 0.30 l/min) for the overall group, with lower and upper limits of agreement at -1.98 and 2.05 l/min, respectively. There was no statistically significant difference in means between both CO measures (P = 0.785). Statistically significant correlations between TTE and Antares CO were observed in the entire cohort (r = 0.705, P<0.001) as well as in female (r = 0.802, P<0.001) and male patients (r = 0.669, P<0.001). CONCLUSIONS: The oscillometric PWA algorithm Antares and established TTE for a non-invasive estimation of CO are highly correlated in male and female patients, with no statistically significant difference between both approaches. Future validation studies of the Antares CO are necessary before a clinical application can be considered.


Subject(s)
Algorithms , Cardiac Output , Echocardiography, Doppler , Pulse Wave Analysis , Humans , Male , Female , Cardiac Output/physiology , Aged , Pulse Wave Analysis/methods , Echocardiography, Doppler/methods , Middle Aged , Aged, 80 and over , Oscillometry/methods
3.
BMC Nurs ; 23(1): 144, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38429782

ABSTRACT

BACKGROUND: To analyse the nature of medical or technical emergency issues of ambulatory peritoneal dialysis (PD) patients calling a nurse-provided emergency PD support service of a reference centre that is provided all year in the after-hours. METHODS: We retrospectively analysed patients' chief complaint, urgency, resolution of and association to current PD treatment and modality directed to an on-call nurse-provided PD support service from 2015-2021 based on routinely collected health data. Calls were systematically categorized being technical/procedural-, medical-, material-related or type of correspondence. Call urgency was categorized to have "immediate consequence", inquiry was eligible for "processing next working day" or whether there was "no need for further action". Call outcomes were classified according to whether patients were able to initiate, resume or finalize their treatments or whether additional interventions were required. Unexpected adverse events such as patients' acute hospitalization or need for nurses' home visits were evaluated and quantified. RESULTS: In total 753 calls were documented. Most calls were made around 7:30 a.m. (5:00-9:00; median, 25-75th CI) and 6:30 p.m. (5:00-8:15). 645 calls were assigned to continuous ambulatory- (CAPD) or automated PD (APD). Of those, 430 calls (66.7%) had an "immediate consequence". Of those 77% (N = 331) were technical/procedural-, 12.8% (N = 55) medical- and 6.3% (N = 27) material related issues. 4% (N = 17) were categorized as other correspondence. Issues disrupting the course of PD were identified in 413 cases. In 77.5% (N = 320) patients were able to initiate, resume or finalize their treatment after phone consultation. Last-bag exchange was used in 6.1% enabling continued therapy in 83.6%. In 35 cases a nurse visit at patients' home or patients' visit to the practice at the earliest possible date were required, while hospitalization was required in seven medical category cases (5.4% and 1.09% of total assessed calls, respectively). CONCLUSION: The on-call PD-nurse provides patient support for acute and imminent issues enabling them to successfully initiate, resume or finalize their prescribed treatment. Nurses triage of acute conditions facilitated rapid diagnostics and therapy. Maintaining quality PD homecare, the provision of trained personnel is indispensable. The information gathered in this study may therefore be used as a foundation to tailor educational programs for nephrology nurses and doctors to further develop their competencies in PD.

4.
PLoS One ; 18(12): e0294075, 2023.
Article in English | MEDLINE | ID: mdl-38096242

ABSTRACT

BACKGROUND: Obesity is a global health concern and risk factor for cardiovascular disease. The assessment of central blood pressure (cBP) has been shown to improve prediction of cardiovascular events. However, few studies have investigated the impact of obesity on cBP in adults, and invasive data on this issue are lacking. This study aimed to evaluate cBP differences between patients with and without obesity, identify cBP determinants, and evaluate the accuracy of the algorithm Antares for non-invasive cBP estimation. METHODS: A total of 190 patients (25% female; 39% with BMI ≥30kg/m2; age: 67±12 years) undergoing elective cardiac catheterization were included. cBP was measured invasively and simultaneously estimated non-invasively using the custo screen 400 device with integrated Antares algorithm. RESULTS: No significant cBP differences were found between obese and non-obese patients. However, females, especially those with obesity, had higher systolic cBP compared to males (P<0.05). Multiple regression analysis showed that brachial mean arterial pressure, pulse pressure, BMI, and heart rate predicted cBP significantly (adjusted R2 = 0.82, P<0.001). Estimated cBP correlated strongly with invasive cBP for systolic, mean arterial, and diastolic cBP (r = 0.74-0.93, P<0.001) and demonstrated excellent accuracy (mean difference <5 and SD <8 mmHg). CONCLUSIONS: This study discovered no significant difference in cBP between obese and non-obese patients. However, it revealed higher cBP values in women, especially those with obesity, which requires further investigation. Additionally, the study highlights Antares' effectiveness in non-invasively determining cBP in obese individuals. This could improve the diagnosis and treatment of hypertension in this special patient population.


Subject(s)
Blood Pressure Determination , Hypertension , Male , Adult , Humans , Female , Middle Aged , Aged , Blood Pressure/physiology , Obesity/complications , Obesity/diagnosis , Diagnostic Techniques, Cardiovascular
5.
Cladistics ; 39(5): 437-455, 2023 10.
Article in English | MEDLINE | ID: mdl-37428134

ABSTRACT

Morphological matrices, including the conceptualization of characters and character states and scoring thereof, still are a valuable and necessary tool for phylogenetic analyses. Although they are often seen only as numerically simplified summaries of observations for the purpose of cladistic analyses, they also hold value as collections of ideas, concepts and the current state of knowledge, conveying various hypotheses on character state identity, homology and evolutionary transformations. A common and persistent issue in scoring and analysing morphological matrices is the phenomenon of inapplicable characters ("inapplicables"). Inapplicables result from the ontological dependency (based on hierarchical relationships) between characters. Traditionally handled the same as "missing data", inapplicables were shown to be problematic in holding the potential to result in unreasonable algorithmic preference for certain cladograms over others. Recently, though, this problem has been solved by approaching parsimony as a maximization of homology rather than a minimization of transformational steps. We herein aim to further improve our theoretical understanding of the underlying hierarchical nature of morphological characters, which causes the phenomenon of ontological dependencies and, thereby, inapplicables. As a result, we present a discussion of various character-dependency scenarios and a new concept of hierarchical character relationships as being composed of four complementary sub-aspects. Building on this, a new syntax for the designation of character dependencies as part of the character statement is proposed, to help identify and apply scoring constraints for manual and automated scoring of morphological character matrices and their cladistic analysis.


Subject(s)
Biological Evolution , Knowledge , Phylogeny
6.
Phys Rev Lett ; 130(17): 173201, 2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37172237

ABSTRACT

We demonstrate that x-ray fluorescence emission, which cannot maintain a stationary interference pattern, can be used to obtain images of structures by recording photon-photon correlations in the manner of the stellar intensity interferometry of Hanbury Brown and Twiss. This is achieved utilizing femtosecond-duration pulses of a hard x-ray free-electron laser to generate the emission in exposures comparable to the coherence time of the fluorescence. Iterative phasing of the photon correlation map generated a model-free real-space image of the structure of the emitters. Since fluorescence can dominate coherent scattering, this may enable imaging uncrystallised macromolecules.

7.
BMJ Health Care Inform ; 30(1)2023 Jan.
Article in English | MEDLINE | ID: mdl-36724909

ABSTRACT

OBJECTIVES: Connecting medical devices to hospital IT networks can create threats that must be covered by IT risk management. In practice, implementing such risk management is not trivial because the IEC 80001-1, as the existing state-of-the-art, do not describe sufficiently concrete implementation measures or evaluation indicators. The aim of the present work was to develop and evaluate a catalogue of measures and indicators to help hospitals implement and evaluate risk management in accordance with IEC 80001-1. METHODS: We conducted a Delphi study with 22 experts. In the first round, we performed interviews to identify implementation measures and evaluation indicators using qualitative content analysis. In the second round, a quantitative experts' survey confirmed the results of the first survey round and identified relationships between the measures and indicators. Based on these results, we then developed a catalogue containing the identified measures and indicators. Finally, we performed a case study to verify the practicability of this catalogue. RESULTS: We developed and verified a catalogue of 49 measures and 18 indicators to help hospitals implement and evaluate risk management following IEC 80001-1. The case study confirmed the practicability of the catalogue. DISCUSSION: Compared with IEC 80001-1, our catalogue goes into further detail to offer hospitals a stepwise implementation and evaluation approach. However, the catalogue must be tested in further case studies and evaluated in terms of generalisation. CONCLUSIONS: The catalogue will enable hospitals to overcome recent difficulties in implementing and evaluating IT risk management for medical devices according to IEC 80001-1.


Subject(s)
Hospitals , Risk Management , Humans
8.
Cladistics ; 39(3): 240-248, 2023 06.
Article in English | MEDLINE | ID: mdl-36738298

ABSTRACT

In the field of phylogenetic systematics, the terms homology and homologue and their relationship to cladistic terms such as character, character state, synapomorphy and symplesiomorphy, as well as their relationships to each other, have been and are still discussed frequently. A recent re-emergence of concepts of homology/homologue free of any reference to explanatory hypotheses prompted us to explore these concepts and their relationships to each other as well as to the concept of morpheme, as introduced recently. All concepts are examined with regard to their ontological status and their bearing in the epistemological process in morphology and phylogenetic systematics. To us, morphemes, homologues and in partem character states refer to things (concrete objects in the ontological sense). However, although morphemes are exclusively descriptive, the latter two represent objects of causal explanations. Homologue always refers to the things themselves, yet a character state also can be a property or the absence of a thing. In this context, a character as a transformation series of character states does not represent a thing but a natural kind. Character states of one character are connected by homology relationships, i.e. common descent. Synapomorphy and symplesiomorphy represent different states of a single transformation series. A nonexplanatory, purely descriptive, concept of homologues is contradictory to its original as well as the post-Darwinian, evolutionary, concept which refers to causal relationships between parts of organisms and their correspondences in the archetype or ancestor, respectively. Character states, homologues and synapomorphies/symplesiomorphies can only be approximated in the form of hypotheses. We argue that the high value of the concept of homology and its related concepts for evolutionary biology should be maintained by acknowledging their explanatory nature and that dilution with nonexplanatory (even idealistic) definitions should be avoided.


Subject(s)
Biological Evolution , Knowledge , Phylogeny
9.
Article in English | MEDLINE | ID: mdl-36707104

ABSTRACT

INTRODUCTION: Antares is a pulse wave analysis (PWA) algorithm designed to allow a non-invasive estimation of central (aortic) blood pressure (cBP) using automated oscillometric blood pressure (BP) devices. Diabetes may affect elastic and muscular arteries differently, resulting in disparate pulse wave characteristics in central and peripheral arteries, which may limit the accuracy of PWA devices. The aim of our study was to evaluate the accuracy of Antares for estimating cBP as compared with invasively measured cBP in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: In this study, consecutive patients undergoing elective coronary angiography were recruited between November 2017 and September 2020. In 119 patients with type 2 diabetes, cBP was measured invasively and simultaneously determined non-invasively using the custo screen 400 device with the integrated Antares algorithm. RESULTS: The mean difference between the estimated and invasively measured cBP was 1.2±6.3 mmHg for central systolic BP (cSBP), 1.0±4.3 mmHg for central mean arterial pressure (cMAP) and 3.6±5.7 mmHg for central diastolic BP (cDBP). High correlations were found between estimated cBP and invasively measured cBP (cSBP: r=0.916; cMAP: r=0.882; cDBP: r=0.791; all p<0.001). CONCLUSIONS: The present study suggests that the Antares algorithm incorporated into the custo screen 400 device can estimate cBP with high accuracy turning a conventional oscillometric BP device into a type II device for the non-invasive estimation of cBP, which is applicable in patients with type 2 diabetes. Integration of Antares into commercially available BP devices could facilitate the introduction of cBP into routine clinical practice as a part of disease and risk management.


Subject(s)
Arm , Diabetes Mellitus, Type 2 , Humans , Blood Pressure/physiology , Blood Pressure Determination/methods , Diabetes Mellitus, Type 2/diagnosis , Pulse Wave Analysis
10.
Molecules ; 29(1)2023 Dec 30.
Article in English | MEDLINE | ID: mdl-38202800

ABSTRACT

Seven new 1,2,3,4,5-pentathiepino[6,7-a]indolizines were synthesized in which the pentathiepine moieties bear an indolizine backbone that is derivatized from C-H to F-, Cl-, Br-, I-, NO2-, and CH3-substitutions, respectively, in a meta position relative to the aza group on the pyridine moiety. Their preparation took place via two common steps: (i) a Sonogashira coupling between (4-substituted) 2-bromo- or 2-chloropyridines and propynyl 3,3-diethylacetal, and (ii) a ring closing reaction mediated by a molybdenum oxo-bistetrasulfido complex and elemental sulfur. The latter simultaneously facilitates the 1,2,3,4,5-pentathiepino chain/ring- and indolizine ring-formations. The fluoro derivative was addressed with 2-bromo-5-aminopyridine as the starting material via a Sandmeyer reaction. The iodo derivative was obtained from 5-bromo-2-alkynylpiridine using a metal-assisted variation of the Finkelstein reaction. The requirement to explore different reaction conditions and the varied respective yields of the final products are discussed. The influence of the distinct substitutions on the pyridine moieties, their electronic structures, and respective chemical properties was investigated through a set of spectroscopic/analytical characterizations. Intriguingly, in all cases, the nitro-substituted derivative exhibited a distinct behavior compared to the six other investigated derivatives, which was also addressed computationally. All seven new pentathiepines were crystallized, and their respective molecular structures were determined using single crystal X-ray diffraction. These structures are compared and discussed as are their respective packing patterns.

11.
Front Immunol ; 13: 930590, 2022.
Article in English | MEDLINE | ID: mdl-36389840

ABSTRACT

The therapeutic targeting of the immune system, for example in vaccinology and cancer treatment, is a challenging task and the subject of active research. Several in silico tools used for predicting immunogenicity are based on the analysis of peptide sequences binding to the Major Histocompatibility Complex (pMHC). However, few of these bioinformatics tools take into account the pMHC three-dimensional structure. Here, we describe a new bioinformatics tool, MatchTope, developed for predicting peptide similarity, which can trigger cross-reactivity events, by computing and analyzing the electrostatic potentials of pMHC complexes. We validated MatchTope by using previously published data from in vitro assays. We thereby demonstrate the strength of MatchTope for similarity prediction between targets derived from several pathogens as well as for indicating possible cross responses between self and tumor peptides. Our results suggest that MatchTope can enhance and speed up future studies in the fields of vaccinology and cancer immunotherapy.


Subject(s)
Major Histocompatibility Complex , Peptides , Histocompatibility Antigens , Cross Reactions , Amino Acid Sequence
12.
Front Zool ; 19(1): 24, 2022 Oct 27.
Article in English | MEDLINE | ID: mdl-36303161

ABSTRACT

Portunoidea (Heterotremata) is a morphologically disparate taxon of true crabs (Brachyura) best-known for many of its representatives being considered "swimming crabs". The term "swimming crab", however, sometimes refers to a distinct taxon (traditionally to Portunidae within Portunoidea), and sometimes to a certain morphotype in which the 5th pereiopod (P5) has a specific shape that facilitates swimming. We use the term "P5-swimming crab" or "P5-swimmer" herein, not only to restrict it to the morphotype, but also to distinguish the swimming in question from other kinds of swimming in Brachyura. The evolution of P5-swimming crabs has not yet been satisfactorily investigated. In particular, it is not known whether the morphotype evolved several times independently in different lineages of Portunoidea or whether it evolved only once and was lost in several lineages. Ours is the first approach combining molecular with morphological data to result in a new phylogenetic positioning of some members of Portunoidea. For the first time, data from the axial skeleton and extrinsic musculature are used. Morphological examinations reveal that the axial skeleton and extrinsic musculature in P5-swimming crabs are more diverse than previously thought, with the exception of the P5 anterior coxa muscle, which originates at the median plate in all P5-swimmers. Ancestral state reconstructions based on parsimony reveal that the stem species of Portunoidea already showed the morphotype of a P5-swimming crab, but with a long merus which probably resulted in less effective P5-swimming than in extant P5-swimming crab species with a short merus. Several other extant taxa represent a reversal of the P5-swimmer morphotype to varying degrees, with some extant species showing a complete reversal of unambiguous P5-swimming crab character states-one example being the well-known common shore crab Carcinus maenas. The absence of a connection between interosternite 7/8 and the sella turcica (the secondary loss of the "brachyuran sella turcica") in the stem species of Heterotremata, resulting in a junction plate which forms a cavity that offers room and attachment sites for the P5 extrinsic musculature is uncovered as preadaptation to the P5-swimmer morphotype in Heterotremata. This preadaptation is missing in Podotremata and Thoracotremata, the other two traditional main taxa of Brachyura.

13.
J Exp Zool B Mol Dev Evol ; 338(6): 342-359, 2022 09.
Article in English | MEDLINE | ID: mdl-35486026

ABSTRACT

Body organization within arthropods is enormously diverse, but a fusion of segments into "functional groups" (tagmatization) is found in all species. Within Tetraconata/Pancrustacea, an anterior head, a locomotory thorax region, and a posterior, mostly limbless tagma known as the abdomen is present. The posterior-most tagma in crustaceans is frequently confused with the malacostracan, for example, decapod pleon often misleadingly termed abdomen, however, its evolutionary and developmental origin continues to pose a riddle, especially the completely limbless abdomen of the "entomostracan morphotype" (e.g., fairy shrimps). Since the discovery of Hox genes and their involvement in specifying the morphology or identity of segments, tagmata, or regions along the anteroposterior axis of an organism, only a few studies have focused on model organisms representing the "entomostracan morphotype" and used a variety of dedicated Hox genes and their transcription products to shine light on abdomen formation. The homeotic genes or the molecular processes that determine the identity of the entomostracan abdomen remain unknown to date. This study focuses on the "entomostracan morphotype" representative Derocheilocaris remanei (Mystacocarida). We present a complete overview of development throughout larval stages and investigate homeotic gene expression data using the antibody FP6.87 that binds specifically to epitopes of Ultrabithorax/Abdominal-A proteins. Our results suggest that the abdomen in Mystacocarida is bipartite (abdomen I + abdomen II). We suggest that the limbless abdomen is an evolutionary novelty that evolved several times independently within crustaceans and which might be the result of a progressive reduction of former thoracic segments into abdominal segments.


Subject(s)
Arthropods , Animals , Arthropods/genetics , Body Patterning , Crustacea/anatomy & histology , Crustacea/genetics , Crustacea/metabolism , Gene Expression Regulation, Developmental , Genes, Homeobox , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Proteins
14.
Chem Commun (Camb) ; 58(19): 3122-3125, 2022 Mar 03.
Article in English | MEDLINE | ID: mdl-35113113

ABSTRACT

The activation of atmospheric molecular dioxygen (O2) is reported, which occurred across a C(sp3)-C(sp3) bond of a piperazine derivative without any catalyst at ambient conditions under the formation of 1,2,4,7-dioxadiazoctane, an 8-membered (larger-ring) cyclic organic peroxide.

15.
J Biol Chem ; 298(2): 101507, 2022 02.
Article in English | MEDLINE | ID: mdl-34929169

ABSTRACT

Heparin, a naturally occurring glycosaminoglycan, has been found to have antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative virus of COVID-19. To elucidate the mechanistic basis for the antiviral activity of heparin, we investigated the binding of heparin to the SARS-CoV-2 spike glycoprotein by means of sliding window docking, molecular dynamics simulations, and biochemical assays. Our simulations show that heparin binds at long, positively charged patches on the spike glycoprotein, thereby masking basic residues of both the receptor-binding domain (RBD) and the multifunctional S1/S2 site. Biochemical experiments corroborated the simulation results, showing that heparin inhibits the furin-mediated cleavage of spike by binding to the S1/S2 site. Our simulations showed that heparin can act on the hinge region responsible for motion of the RBD between the inactive closed and active open conformations of the spike glycoprotein. In simulations of the closed spike homotrimer, heparin binds the RBD and the N-terminal domain of two adjacent spike subunits and hinders opening. In simulations of open spike conformations, heparin induces stabilization of the hinge region and a change in RBD motion. Our results indicate that heparin can inhibit SARS-CoV-2 infection by three mechanisms: by allosterically hindering binding to the host cell receptor, by directly competing with binding to host heparan sulfate proteoglycan coreceptors, and by preventing spike cleavage by furin. Furthermore, these simulations provide insights into how host heparan sulfate proteoglycans can facilitate viral infection. Our results will aid the rational optimization of heparin derivatives for SARS-CoV-2 antiviral therapy.


Subject(s)
COVID-19/metabolism , Heparin/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Antiviral Agents/pharmacology , Binding Sites , Heparin/chemistry , Heparin/pharmacology , Humans , Molecular Docking Simulation , Molecular Dynamics Simulation , Protein Binding , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/chemistry , COVID-19 Drug Treatment
16.
J Am Chem Soc ; 143(40): 16448-16457, 2021 10 13.
Article in English | MEDLINE | ID: mdl-34559523

ABSTRACT

Advances in supramolecular chemistry are often underpinned by the development of fundamental building blocks and methods enabling their interconversion. In this work, we report the use of an underexplored dynamic covalent reaction for the synthesis of stimuli-responsive [2]rotaxanes. The formamidinium moiety lies at the heart of these mechanically interlocked architectures, because it enables both dynamic covalent exchange and the binding of simple crown ethers. We demonstrated that the rotaxane self-assembly follows a unique reaction pathway and that the complex interplay between crown ether and thread can be controlled in a transient fashion by addition of base and fuel acid. Dynamic combinatorial libraries, when exposed to diverse nucleophiles, revealed a profound stabilizing effect of the mechanical bond as well as intriguing reactivity differences between seemingly similar [2]rotaxanes.


Subject(s)
Rotaxanes
17.
Phys Rev Lett ; 126(17): 173602, 2021 Apr 30.
Article in English | MEDLINE | ID: mdl-33988402

ABSTRACT

Cross-correlation signals are recorded from fluorescence photons scattered in free space off a trapped ion structure. The analysis of the signal allows for unambiguously revealing the spatial frequency, thus the distance, as well as the spatial alignment of the ions. For the case of two ions we obtain from the cross-correlations a spatial frequency f_{spatial}=1490±2_{stat}±8_{syst} rad^{-1}, where the statistical uncertainty improves with the integrated number of correlation events as N^{-0.51±0.06}. We independently determine the spatial frequency to be 1494±11 rad^{-1}, proving excellent agreement. Expanding our method to the case of three ions, we demonstrate its functionality for two-dimensional arrays of emitters of indistinguishable photons, serving as a model system to yield structural information where direct imaging techniques fail.

18.
Zoology (Jena) ; 144: 125883, 2021 02.
Article in English | MEDLINE | ID: mdl-33465734

ABSTRACT

Anaspidacea is probably the most enigmatic higher taxon within the Malacostraca. Representatives of the genus Anaspides are often considered "living fossils" due to their strong resemblance to their Triassic relatives. In comparison to other extant Malacostraca, they possess a high number of plesiomorphic characters. Anaspidacea are often combined with another freshwater taxon, Bathynellacea, into the Syncarida, but actual evidence for monophyletic Syncarida is weak. Other potential sister groups are Eucarida, Euphausiacea, or Euphausiacea + Peracarida. Like Euphausiacea, Mysidacea and "natant" decapods, Anaspidacea show what has been called a "caridoid facies". In malacostracan crustaceans, a prominent mode of locomotion is swimming, as it almost certainly was for the malacostracans' common ancestor. However, when considered in detail, swimming is found to take quite different forms in the various taxa. To obtain a better understanding of the evolution of swimming, we analyzed locomotion in several species of Anaspides endemic to Tasmania. The morphology of the protopodal and exopodal musculature as well as the exo- and endoskeletal structures of the thoracopods were examined using 3D reconstruction of CLSM- and µCT data. Various aspects of locomotion were documented and described using recording techniques including in-habitat underwater filming and macro high-speed recording. Our analysis shows the high level of complexity of the muscular arrangement and skeletal construction in the thoracopods of these - in many regards plesiomorphic - malacostracans, and demonstrates the presence of epipodal musculature. Our recordings provide insight into various aspects of locomotion of Anaspides, including the congruence of locomotive kinematics in swimming and walking. Our morphological findings and observations on locomotion in Anaspides are compared to findings in other malacostracan shrimps and discussed in a phylogenetic context, with our analysis providing further support for Xenommacarida (sensuRichter, 1999: Anaspidacea + Euphausiacea + Peracarida). Further, a new hypothesis for the origin of the ventral brood pouch, the marsupium, of Peracarida is discussed. On the basis of a comparison of their morphology and biology, the oostegites which form the marsupium are suggested to be derived thoracopodal endites as present in female Anaspides. Finally, an evolutionary scenario is presented and mapped on a cladogram in which the evolution of malacostracan swimming from a common caridoid ancestor up to the different taxa present today is discussed.


Subject(s)
Arthropods/physiology , Extremities/physiology , Motor Activity/physiology , Swimming/physiology , Walking/physiology , Animals
19.
Ind Eng Chem Res ; 60(51): 18791-18805, 2021 Dec 29.
Article in English | MEDLINE | ID: mdl-34992332

ABSTRACT

Porous SiO2 nanospheres were modified with different loadings of ZrO2 to obtain catalysts with a Si/Zr molar ratio from 2.5 to 30. These materials were characterized by X-ray diffraction, transmission and scanning electron microscopies, N2 adsorption-desorption at -196 °C, X-ray photoelectron spectroscopy and pyridine and 2-6-dimethylpyridine thermoprogrammed desorption. The characterization of these catalysts has revealed that a high proportion of Zr favors the formation of Lewis acid sites, which are implied in catalytic transfer hydrogenation processes, whereas the low Brönsted acidity promotes a dehydration reaction, being possible to give rise to a large variety of products from furfural through consecutive reactions, such as furfuryl alcohol, i-propyl furfuryl ether, i-propyl levulinate, and γ-valerolactone, in a range of temperature of 110-170 °C and 1-6 h of reaction.

20.
Zool Stud ; 59: e44, 2020.
Article in English | MEDLINE | ID: mdl-33365101

ABSTRACT

Spinicaudata (spiny clam shrimp) is a taxon of Branchiopoda occurring since the Devonian and today it occurs nearly globally in temporary water bodies. We present the most species-rich phylogenetic analyses of this taxon based on four molecular loci: COI, 16S rRNA, EF1α and 28S rRNA. Our results support previous findings that Cyzicidae sensu lato is paraphyletic. To render Cyzicidae monophyletic we establish a fourth extant spinicaudatan family to accommodate Eocyzicus. Within Cyzicidae, none of the genera Cyzicus, Caenestheria or Caenestheriella are monophyletic, and the morphological characters used to define these genera (condyle length and rostrum shape) are not associated with well-delimited clades within Cyzicidae. There is insufficient resolution to elucidate the relationships within Leptestheriidae. However, there is sufficient evidence to show that the leptestheriid genera Eoleptestheria and Leptestheria are non-monophyletic, and there is no support for the genus Leptestheriella. Molecular clock analyses suggest that the wide geographic distribution of many spinicaudatan taxa across multiple continents is largely based on vicariance associated with the break-up of Pangea and Gondwana. Trans-oceanic dispersal has occurred in some taxa (e.g., Eulimnadia and within Leptestheriidae) but has been relatively rare. Our results highlight the need to revise the taxonomy of Cyzicidae and Leptestheriidae and provide evidence that the global spinicaudatan diversity may be underestimated due to the presence of numerous cryptic species. We establish Eocyzicidae fam. nov. to accommodate the genus Eocyzicus. Consequently, Cyzicidae comprises only two genera -Cyzicus and Ozestheria. Ozestheria occurs also in Africa and Asia and Ozestheria pilosa new comb. is assigned to this genus.

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