bluuebunny/crossref_metadata_2025 huggingface dataset:
ASV station keeping under wind disturbances using neural network simulation error minimization model predictive control
Authors: Chavez‐Galaviz Jalil , Li Jianwen , Chaudhary Ajinkya , Mahmoudian Nina
Published: April 2024

Station keeping is an essential maneuver for autonomous surface vehicles (ASVs), mainly when used in confined spaces, to carry out surveys that require the ASV to keep its position or in collaboration with other vehicles where the relative position has an impact over the mission. However, this maneuver can become challenging for classic feedback controllers due to the need for an accurate model of the ASV dynamics and the environmental disturbances. This work proposes a model predictive controller using neural network simulation error minimization (NNSEM–MPC) to accurately predict the dynamics of the ASV under wind disturbances. The performance of the proposed scheme under wind disturbances is tested and compared against other controllers in simulation, using the robotics operating system and the multipurpose simulation environment Gazebo. A set of six tests was conducted by combining two varying wind speeds that are modeled as the Harris spectrum and three wind directions (, , and ). The simulation results clearly show the advantage of the NNSEM–MPC over the following methods: backstepping controller, sliding mode controller, simplified dynamics MPC (SD‐MPC), neural ordinary differential equation MPC (NODE‐MPC), and knowledge‐based NODE MPC. The proposed NNSEM–MPC approach performs better than the rest in five out of the six test conditions, and it is the second best in the remaining test case, reducing the mean position and heading error by at least % ( m) and % (), respectively, across all the test cases. In terms of execution speed, the proposed NNSEM–MPC is at least 36% faster than the rest of the MPC controllers. The field experiments on two different ASV platforms showed that ASVs can effectively keep the station utilizing the proposed method, with a position error as low as  m and a heading error as low as within time windows of at least  s. This would increase the potential applications of ASVs for launch, recovery, and replenishment in long‐term surveys in collaboration with other autonomous systems.
Unoccupied aerial vehicles as a tool to map lizard operative temperature in tropical environments
Authors: Higgins Emma A. , Boyd Doreen S. , Brown Tom W. , Owen Sarah C. , van der Heijden Geertje M. F. , Algar Adam C.
Published: April 2024

To understand how ectotherms will respond to warming temperatures, we require information on thermal habitat quality at spatial resolutions and extents relevant to the organism. Measuring thermal habitat quality is either limited to small spatial extents, such as with ground‐based 3D operative temperature (Te) replicas, representing the temperature of the animal at equilibrium with its environment, or is based on microclimate derived from physical models that use land cover variables and downscale coarse climate data. We draw on aspects of both these approaches and test the ability of unoccupied aerial vehicle (UAV) data (optical RGB) to predict fine‐scale heterogeneity in sub‐canopy lizard (Anolis bicaorum) Te in tropical forest using random forest models. Anolis bicaorum is an endemic, critically endangered, species, facing significant threats of habitat loss and degradation, and work was conducted as part of a larger project. Our findings indicate that a model incorporating solely air temperature, measured at the centre of the 20 × 20 m plot, and ground‐based leaf area index (LAI) measurements, measured at directly above the 3D replica, predicted Te well. However, a model with air temperature and UAV‐derived canopy metrics performed slightly better with the added advantage of enabling the mapping of Te with continuous spatial extent at high spatial resolutions, across the whole of the UAV orthomosaic, allowing us to capture and map Te across the whole of the survey plot, rather than purely at 3D replica locations. Our work provides a feasible workflow to map sub‐canopy lizard Te in tropical environments at spatial scales relevant to the organism, and across continuous areas. This can be applied to other species and can represent species within the same community that have evolved a similar thermal niche. Such methods will be imperative in risk modelling of such species to anthropogenic land cover and climate change.
Enhancing long‐term survival prediction with two short‐term events: Landmarking with a flexible varying coefficient model
Authors: Li Wen , Wang Qian , Ning Jing , Zhang Jing , Li Zhouxuan , Savitz Sean I. , Tahanan Amirali , Rahbar Mohammad H.
Published: April 2024

Patients with cardiovascular diseases who experience disease‐related short‐term events, such as hospitalizations, often exhibit diverse long‐term survival outcomes compared to others. In this study, we aim to improve the prediction of long‐term survival probability by incorporating two short‐term events using a flexible varying coefficient landmark model. Our objective is to predict the long‐term survival among patients who survived up to a pre‐specified landmark time since the initial admission. Inverse probability weighting estimation equations are formed based on the information of the short‐term outcomes before the landmark time. The kernel smoothing method with the use of cross‐validation for bandwidth selection is employed to estimate the time‐varying coefficients. The predictive performance of the proposed model is evaluated and compared using predictive measures: area under the receiver operating characteristic curve and Brier score. Simulation studies confirm that parameters under the landmark models can be estimated accurately and the predictive performance of the proposed method consistently outperforms existing methods that either do not incorporate or only partially incorporate information from two short‐term events. We demonstrate the practical application of our model using a community‐based cohort from the Atherosclerosis Risk in Communities (ARIC) study.
Flexible parametrization of graph‐theoretical features from individual‐specific networks for prediction
Authors: Gregorich Mariella , Simpson Sean L. , Heinze Georg
Published: April 2024

Statistical techniques are needed to analyze data structures with complex dependencies such that clinically useful information can be extracted. Individual‐specific networks, which capture dependencies in complex biological systems, are often summarized by graph‐theoretical features. These features, which lend themselves to outcome modeling, can be subject to high variability due to arbitrary decisions in network inference and noise. Correlation‐based adjacency matrices often need to be sparsified before meaningful graph‐theoretical features can be extracted, requiring the data analysts to determine an optimal threshold. To address this issue, we propose to incorporate a flexible weighting function over the full range of possible thresholds to capture the variability of graph‐theoretical features over the threshold domain. The potential of this approach, which extends concepts from functional data analysis to a graph‐theoretical setting, is explored in a plasmode simulation study using real functional magnetic resonance imaging (fMRI) data from the Autism Brain Imaging Data Exchange (ABIDE) Preprocessed initiative. The simulations show that our modeling approach yields accurate estimates of the functional form of the weight function, improves inference efficiency, and achieves a comparable or reduced root mean square prediction error compared to competitor modeling approaches. This assertion holds true in settings where both complex functional forms underlie the outcome‐generating process and a universal threshold value is employed. We demonstrate the practical utility of our approach by using resting‐state fMRI data to predict biological age in children. Our study establishes the flexible modeling approach as a statistically principled, serious competitor to ad‐hoc methods with superior performance.
Synthesis and Biofunctional Properties of NaBr/H2O2‐Induced Brominated Uracil Derivatives
Authors: Shivangi  , Das Subrata , Mal Susital , Naskar Shibu
Published: April 2024

Bromouracil derivatives are synthesized using an environmentally acceptable bromination protocol involving NaBr as a promoter. A minimum of 1.5 equivalent NaBr was required to reach the maximum yield. The reactions were conducted in an acidic medium in the presence of H2O2 under ambient conditions. We successfully synthesized ten novel 5‐bromouracil derivatives available in our laboratory and characterized them using various spectroscopic methods such as 1H‐NMR, 13C‐NMR, and SC‐XRD. All the derivatives are screened for anti‐bacterial activities against gram‐positive and gram‐negative bacteria. In particular, compounds 5‐bromo‐4‐chloro‐6‐methylpyrimidin‐2‐amine and 5‐bromo‐6‐chloropyrimidine‐2,4‐diamine exhibited prominent antibacterial activity against gram‐negative E. coli with IC50 values of ~9.8 and ~5.7 μg/mL. The structural‐activity relationship revealed that the presence of the −NH2 group in both the bromo derivatives affirms improving activity. Molecular docking studies also supported the experimental result and showed good binding energy of −4.4 (2 a) and −4.8 (2 b) kcal/mol against E. coli primase.
A Portable Polymer‐based Sensor Platform for the Detection of Atrazine
Authors: Comnea‐Stancu Ionela Raluca , van Staden Jacobus (Koos) Frederick , Stefan‐van Staden Raluca‐Ioana
Published: April 2024

Despite being banned by the European Union (EU), Atrazine, a synthetic herbicide, was found in Europe's coastal waters. Given the widespread ban on atrazine in many countries, it is imperative to perform screenings to detect its presence in food and water samples, as it poses significant risks to both human health and aquatic ecosystems. This study presents the development of an innovative, simple, and cost‐effective electrochemical sensing platform that comprises a portable system equipped with a poly‐8‐Amino‐1‐naphthol‐3,6‐disulfonic acid (8‐ANDSA) customized carbon paste electrode (CPE). The poly‐8 ANDSA/CPE was acquired using the process of electrochemical polymerization, utilizing cyclic voltammetry (CV) over the potential domain of −0.8 V to 1.8 V for 25 sweep cycles. The poly‐8‐ANDSA/CPE exhibited a linear relationship between the square wave voltammetric (SWV) peak current amplitude and ATZ concentration within 0.1–100 μM. The limit of detection for ATZ was determined to be 30 nM. Spiked recovery results of 97.71 % to 102.73 % with RSD (%) values less than 5 % validated the method‘s applicability for atrazine detection from water samples. The favorable outcomes indicated that the portable system performs exceptionally well and validates the practicality of ATZ detection, facilitating on‐site detection in actual water samples.
Competition between Transport and Recombination in Dye Solar Cells at Low Light Intensity
Authors: Sánchez‐Fernández Patricia , Aranda Clara A. , Escalante Renán , Riquelme Antonio J. , Demadrille Renaud , Pistor Paul , Oskam Gerko , Anta Juan A.
Published: April 2024

The efficiency of electron collection in a dye‐sensitized solar cell (DSC) is determined by a delicate balance between electronic transport and recombination losses caused by electron transfer to dye cations and electron acceptors. While state‐of‐the‐art DSCs have demonstrated quantitative electron collection under standard 1 sun conditions, the nonlinear nature of the trapping/detrapping dynamics in the photoanode with respect to the stored electronic charge can result in suboptimal performance under the low illumination intensity conditions commonly found indoors. Herein, the key factors influencing electron collection in relation to light intensity using impedance spectroscopy and numerical analysis are thoroughly examined. Impedance analysis reveals that the electron diffusion length tends to decrease as the quasi‐Fermi level is lowered, approaching the critical limit (Ln/d ≈ 1) at intensities characteristic of indoor illumination. A range of tert‐butyl pyridine concentrations and different thermal and chemical treatments of the TiO2 are tested, showing that this low intensity limitation is inherent to the multiple‐trapping mechanism that governs the functioning of a DSC. It is concluded that relatively high ideality factors, nonoptimal electrolyte compositions, or small variations in the quality of the TiO2 layer can result in electron collection limitations that are not apparent under 1 sun but become noticeable at low light intensities.
Influence of additional prophylactic oral antibiotics during mechanical bowel preparation on surgical site infection in patients receiving colorectal surgery
Authors: Lee Hayoung , Lee Jong Lyul , Lee Ji Sung , Kim Chan Wook , Yoon Yong Sik , Park In Ja , Lim Seok‐Byung
Published: April 2024

Background

Prophylactic antibiotics (PAs) are standard for preventing surgical site infections (SSIs) post‐colorectal surgery. This study aims to compare the effect of additional empiric oral antibiotics (OAs) alongside routine PAs to identify SSI risk factors.

Methods

A retrospective observatory analysis was conducted from January 2019 to December 2022 at Asan Medical Center, Seoul, Korea. The cohort was divided into two groups: PA given 1 h before surgery and discontinued within 24 h, and OA administered empiric OAs during mechanical bowel preparation in addition to PA.

Results

From a total of 6736 patients, 3482 were in the PA group and 3254 in the OA group. SSI incidence showed no significant intergroup difference (p = 0.374) even after propensity score matching (p = 0.338). The multivariable analysis revealed male sex [odds ratio (OR): 2.153, 95% confidence interval (CI): 1.626–2.852, and p = 0.001], open surgery (OR: 3.335, 95% CI: 2.456–4.528, and p = 0.001), dirty wound (OR: 2.171, 95% CI: 1.256–3.754, and p = 0.006), and an operation time of more than 145 min (OR: 2.110, 95% CI: 1.324–3.365, and p = 0.002) as SSI risk factors. In rectal surgery subgroup, OA demonstrated a protective effect against SSI (OR: 0.613, 95% CI: 0.408–0.922, and p = 0.019) and in laparoscopic approach (OR: 0.626, 95% CI: 0.412–0.952, and p = 0.028).

Conclusions

OA did not affect SSI incidence in colorectal surgeries. Male sex, open surgery, dirty wounds, and longer operation time were risk factors for SSI. However, for rectal and laparoscopic surgery, OA was a protective factor for SSI.
The Francophone Postcolonial Thinkers and the Colonizer-Colonized Dialectic
Authors: Singh Kundan , Maheshwari Krishna
Published: April 2024

The invidious relationship between the colonizer and colonized is locked in a dialectical and reciprocal relationship. The history of colonization of non-European people by the Europeans reveals that the colonizer created a mythical representation of the colonized surrounding savagery, barbarity, uncouthness, and uncivilization to show themselves as civilized, noble, and refined. The intellectuals of the colonizing empire participated in the construction of this discourse, which essentially is racist. Francophone postcolonial thinkers like Aimé Césaire, Franz Fanon, and Albert Memmi have systematically unfolded the colonizer-colonized relationship. This chapter, beginning with their biographies, discusses their contentions to create a framework in which James Mill’s History of British India is critically evaluated in the subsequent two chapters.
Damaging Psychological Consequences of the Discourse
Authors: Singh Kundan , Maheshwari Krishna
Published: April 2024

However politically correct a racist discourse may be, it has negative consequences on the psyche of the people toward whom it is directed. Research has shown that children are most suspectable and vulnerable to racist discourse. When subjected to racist discourse, they develop an inferiority complex, resulting in low self-esteem and lack of self-worth. They build defense mechanisms to dissociate themselves from their ancestors’’ ethnicity, nationality, or culture. The sanitized and politically correct discourse of Mill in current school textbooks, which remains racist because of the history that it has inherited, has profound psychological and sociological consequences for Indian American children that this chapter comprehensively exposes.
Empirischer Zugang
Authors: Holztrattner Melanie
Published: April 2024

Vor dem Hintergrund einer praxeologischen Analysefolie, welche einen Zugriff „auf die soziale Praxis des Pädagogischen bzw. pädagogischer Ordnungen“ (Schmidt, 2018, S. 9) bzw. einen Blick auf die (soziokulturelle) Praxis im Kontext von Arrangements von Praktiken ‚früher Kindheit(en)‘ (vgl. Honig, 2018, S. 204 ff) erlaubt, versteht sich die vorliegende Schrift als rekonstruktiv. Dieser Zugang fragt nach dem wie der Herstellung sozialer Praxis und ermöglicht, „denjenigen, die Gegenstand der Forschung sind, Gelegenheit [zu geben], ihre Konstruktionen und ihr kommunikatives Regelsystem zu entfalten“ (Bohnsack, 2010, S. 24). Das hierbei konstitutive Moment der Offenheit ermöglicht, dass „die Strukturierung der Kommunikation im Rahmen des für die Untersuchung relevanten Themas so weit wie möglich [den Beforschten] überlassen [werden kann], damit diese ihr Relevanzsystem und ihr kommunikatives Regelsystem entfalten können und auf diesem Wege die Unterschiede zum Relevanzsystem des Forschers überhaupt erst erkennbar werden“ (ebd., S. 21).
General hyperstability criteria for Jensen-type equations
Authors: Dăianu Dan M.
Published: April 2024

We provide two large classes of control functions that ensure the hyperstability of Jensen-type equations on restricted domains. Among other consequences, we obtain improvements on similar results known in the literature for some Aoki–Rassias-type control functions and hyperstability results for some equations whose solutions are Jensen functions compounded with radical-type functions or with trigonometric functions.
NovoSorb® Biodegradable Temporizing Matrix: a novel approach for treatment of extremity avulsion injuries in children
Authors: Najem Safiullah , Fattouh Miriam , Wintges Kristofer , Schoof Benjamin , Koerner Merle , Reinshagen Konrad , Koenigs Ingo
Published: April 2024

Purpose

In pediatric population, large soft tissue defects occur in avulsion injuries. In addition to the challenges of primary surgical therapy, elasticity, appearance and function of the scar in children are of crucial importance, especially in the context of body growth. So far various flaps, plasties, skin grafts and dermal substitutes have become established, although infections and skin shrinkage remain challenging. In 2020, a new skin substitute material—NovoSorb® Biodegradable Temporizing Matrix (BTM)—was introduced in Europe for temporary wound closure and tissue regeneration. The aim of this study was to evaluate the value of BTM in pediatric patients.

Methods

The study included all children treated with BTM after traumatic soft tissue defects following limb avulsion injuries between June 2021 and June 2023 at a university hospital.

Results

7 patients with limb avulsion injuries were treated with BTM, 4 boys, 3 girls. Mean age was 6.5 years (2–11 years) at the time of BTM placement. 4/7 had concomitant fractures. BTM was used successfully in all cases, infection did not occur, skin shrinkage was seen in one case. Split thickness skin graft (STSG) after BTM application was performed in average after 33 days (26 to 39 days). Limitations of this study were highlighted.

Conclusion

BTM is a promising alternative for reconstruction of complex trauma extremity wounds in children following avulsion injuries, even in cases of concomitant bone injuries. Interpretation may be limited by sample size.
Die Schwangere mit COVID-19-ARDS auf der Intensivstation
Authors: Kalbhenn J. , Marx O. , Müller-Peltzer K. , Kunze M. , Bürkle H. , Bansbach J.
Published: April 2024

Hintergrund

Schwangere mit einer SARS-CoV-2-Infektion (COVID-19) haben ein erhöhtes Risiko für einen schweren Verlauf der COVID-19. Die medizinische und ethische Abwägung maternaler und fetaler Risiken und die Priorisierung von Therapieoptionen stellen eine große Herausforderung auf der Intensivstation dar. Eine enge interdisziplinäre Abstimmung ist unabdingbar.

Ziel der Arbeit

Beschreibung und Diskussion intensivmedizinischer Behandlungsstrategien und des perinatalen anästhesiologischen Managements bei Patientinnen mit COVID-19-ARDS (CARDS).

Material und Methoden

Analyse von demografischen Daten, Anamnese, klinischem Management, Komplikationen, Indikationen und Management der extrakorporalen Membranoxygenierung (ECMO) sowie des kindlichen Überlebens aller schwangeren Patientinnen, die zwischen März und November 2021 auf der anästhesiologischen Intensivstation eines deutschen Universitätsklinikums wegen eines schweren CARDS behandelt wurden.

Ergebnisse

Kohorte von 9 konsekutiven Patientinnen mit einem Durchschnittsalter von 30,3 Jahren (Min–Max: 26 bis 40 Jahre) und einem Schwangerschaftsalter von 21 + 3 bis 37 + 2 Wochen. Keine der Patientinnen war gegen SARS-CoV‑2 geimpft. Zwei Patientinnen mussten mit inhalativem Stickstoffmonoxid und venovenöser ECMO behandelt werden. Alle Frauen und 5 Neugeborene haben überlebt. Zwei Patientinnen wurden mit intakter Schwangerschaft nach Hause entlassen. Alle Kinder wurden durch einen Kaiserschnitt entbunden. Es wurden 2 intrauterine fetale Todesfälle beobachtet. Keines der Neugeborenen wurde bei der Geburt positiv auf SARS-CoV‑2 getestet.

Diskussion

Das peripartale Management erfordert eine enge interdisziplinäre Zusammenarbeit und sollte in der Frühschwangerschaft vorrangig auf das mütterliche Überleben ausgerichtet sein. Die Bauchlagerung, ein wesentlicher, evidenzbasierter Eckpfeiler in der Therapie des akuten Atemnotsyndroms (ARDS), kann auch in fortgeschrittenen Schwangerschaftsstadien sicher angewendet werden. Inhalatives Stickstoffmonoxid (iNO) und extrakorporale Membranoxygenierung (ECMO) sollten als lebensrettende Behandlungsoptionen für sorgfältig ausgewählte Patientinnen in Betracht gezogen werden.
Discordance between mean glucose and time in range in relation to HbA1c in individuals with type 1 diabetes: results from the GOLD and SILVER trials
Authors: Sterner Isaksson Sofia , Imberg Henrik , Hirsch Irl B. , Schwarcz Erik , Hellman Jarl , Wijkman Magnus , Bolinder Jan , Nyström Thomas , Holmer Helene , Hallström Sara , Ólafsdóttir Arndís F. , Pekkari Sofia , Polonsky William , Lind Marcus
Published: April 2024

Aims/hypothesis

Previous studies have shown that individuals with similar mean glucose levels (MG) or percentage of time in range (TIR) may have different HbA1c values. The aim of this study was to further elucidate how MG and TIR are associated with HbA1c.

Methods

Data from the randomised clinical GOLD trial (n=144) and the follow-up SILVER trial (n=98) of adults with type 1 diabetes followed for 2.5 years were analysed. A total of 596 paired HbA1c/continuous glucose monitoring measurements were included. Linear mixed-effects models were used to account for intra-individual correlations in repeated-measures data.

Results

In the GOLD trial, the mean age of the participants (± SD) was 44±13 years, 63 (44%) were female, and the mean HbA1c (± SD) was 72±9.8 mmol/mol (8.7±0.9%). When correlating MG with HbA1c, MG explained 63% of the variation in HbA1c (r=0.79, p<0.001). The variation in HbA1c explained by MG increased to 88% (r=0.94, p value for improvement of fit <0.001) when accounting for person-to-person variation in the MG–HbA1c relationship. Time below range (TBR; <3.9 mmol/l), time above range (TAR) level 2 (>13.9 mmol/l) and glycaemic variability had little or no effect on the association. For a given MG and TIR, the HbA1c of 10% of individuals deviated by >8 mmol/mol (0.8%) from their estimated HbA1c based on the overall association between MG and TIR with HbA1c. TBR and TAR level 2 significantly influenced the association between TIR and HbA1c. At a given TIR, each 1% increase in TBR was related to a 0.6 mmol/mol lower HbA1c (95% CI 0.4, 0.9; p<0.001), and each 2% increase in TAR level 2 was related to a 0.4 mmol/mol higher HbA1c (95% CI 0.1, 0.6; p=0.003). However, neither TIR, TBR nor TAR level 2 were significantly associated with HbA1c when accounting for MG.

Conclusions/interpretation

Inter-individual variations exist between MG and HbA1c, as well as between TIR and HbA1c, with clinically important deviations in relatively large groups of individuals with type 1 diabetes. These results may provide important information to both healthcare providers and individuals with diabetes in terms of prognosis and when making diabetes management decisions.

Graphical Abstract
On the Brauer groups of fibrations
Authors: Qin Yanshuai
Published: April 2024

Let $${\mathcal {X}}\rightarrow C$$

X
→
C

be a flat k-morphism between smooth integral varieties over a finitely generated field k such that the generic fiber X is smooth, projective and geometrically connected. Assuming that C is a curve with function field K, we build a relation between the Tate-Shafarevich group of $$\textrm{Pic}^0_{X/K}$$

Pic

X
/
K

0

and the geometric Brauer groups of $${\mathcal {X}}$$
X
and X, generalizing a theorem of Artin and Grothendieck for fibered surfaces to higher relative dimensions.
Remarks on the existence of minimal models of log canonical generalized pairs
Authors: Tsakanikas Nikolaos , Xie Lingyao
Published: April 2024

Given an NQC log canonical generalized pair $$(X,B+M)$$

(
X
,
B
+
M
)

whose underlying variety X is not necessarily $$\mathbb {Q}$$
Q
-factorial, we show that one may run a $$(K_X+B+M)$$

(

K
X

+
B
+
M
)

-MMP with scaling of an ample divisor which terminates, provided that $$(X,B+M)$$

(
X
,
B
+
M
)

has a minimal model in a weaker sense or that $$K_X+B+M$$

K
X

+
B
+
M

is not pseudo-effective. We also prove the existence of minimal models of pseudo-effective NQC log canonical generalized pairs under various additional assumptions, for instance when the boundary contains an ample divisor.
Intermediate dimensions under self-affine codings
Authors: Feng Zhou
Published: April 2024

Intermediate dimensions were recently introduced by Falconer et al. (Math Z 296:813–830, 2020) to interpolate between the Hausdorff and box-counting dimensions. In this paper, we show that for every subset E of the symbolic space, the intermediate dimensions of the projections of E under typical self-affine coding maps are constant and given by formulas in terms of capacities. Moreover, we extend the results to the generalized intermediate dimensions introduced by Banaji (Monatsh Math 202: 465–506, 2023) in several settings, including the orthogonal projections in Euclidean spaces and the images of fractional Brownian motions.
Potential benefits of adipose–derived SVF and MSCs to regenerate damaged tissues from alloplastic synthetic materials
Authors: Zocchi Michele L. , Prantl Lukas , Oliinyk Dmytro , Knoedler Leonard , Siegmund Andreas , Ahmad Nura , Duscher Dominik , Larcher Lorenz , Raposio Edoardo , Pagani Andrea
Published: April 2024

Recent advancements in Plastic Surgery and Regenerative MedicineQuery have revolutionized tissue repair, remodeling, and regeneration. A promising approach involves Mesenchymal Stem cells and from the adipose–derived Stromal Vascular Fraction, aimed at improving tissue healing post the use of synthetic materials. This integration shows potential in mitigating adverse effects of synthetic materials like dermal fillers, offering new clinical interventions for tissue repair and regeneration. This article explores the benefits, complications, and applications of these technologies in Plastic Surgery and Cosmetic Medicine, focusing on their mechanisms of action and future perspectives.

 Level of evidence: Not ratable
Multiple relaxation mechanisms in SrBi2Nb2O9 ceramic tweaked by tin and samarium incorporation in assistance with single-step microwave sintering
Authors: Pritam Anurag , Bhattacharya Gourav , Sain Saurav , Shrivastava Vaibhav , Roy Susanta Sinha
Published: April 2024

Non-stoichiometric lead free polycrystalline Sr0.8Sn0.2Bi1.75Sm0.25Nb2O9 (SSBSN) ferroelectric ceramics were synthesized through conventional solid step route method by incorporating ball milling and microwave sintering method. X-ray diffraction along with the Rietveld refinement technique confirms the single-phase orthorhombic structure with A21 crystal symmetry. Additionally, the short-range ordering was confirmed by Raman spectroscopy. Doping induced crystallite size and strain were further calculated from the Williamson-Hall plot, which comes around 150 nm and 1.48 × 10–3 respectively. A plate like morphology with an average grain size of 0.41 μm was confirmed by scanning electron microscopy (SEM). A diffuse type ferroelectric to paraelectric phase transition was recorded at 395 °C, mostly arising due to structural heterogeneity at the inter-ferroelectric phase boundary. The temperature and frequency-dependent dielectric measurement of SSBSN ceramic reveal a Maxwell–Wagner relaxation, with prominent dielectric loss in a low frequency regime perhaps due to the generation of leakage current in the SSBSN system. Frequency dependent ac conductivity indicates the polaron assisted hopping mechanism in SSBSN, which further obeys Jonscher’s formulation. The intra and intergranular contributions to impedance in SSBSN ceramics were probed by the complex impedance spectroscopy (CIS) technique. A non-Debye type relaxation mechanism in SSBSN ceramics was indicated by the Cole–Cole plot, whereas the conduction mechanism and transport properties were briefly studied using modulus spectroscopy.
Comparative analysis of combined spinal–epidural anesthesia and general anesthesia in percutaneous nephrolithotomy: a prospective study on surgical team and operating room personnel satisfaction
Authors: Bürlukkara Salih , Kabalak Afife Ayla , Ateş Alpay , Baran Özer , Aykaç Aykut , Özok Hakkı Uğur
Published: April 2024

Objective

We aimed to investigate the efficacy and complications of combined spinalepidural anesthesia and general anesthesia in percutaneous stone surgery prospectively.

Materials and methods

The study prospectively included patients who underwent percutaneous nephrolithotomy with general anesthesia (Group.1) or combined spinal–epidural anesthesia (Group.2) at the Department of Urology, Training and Research Hospital, Karabuk University. between December 2018 and December 2019. The effect of the anesthesia technique on the comfort and satisfaction of the operating room personnel, surgeon and anesthesia team were prospectively evaluated and recorded.

Results

During the postoperative period, the spinal anesthesia group had a significantly lower visual analog score than the general anesthesia group. No patient in either group required narcotic analgesics during the postoperative period. In terms of overall satisfaction scores, the surgeon performing the surgical procedure had a significantly higher satisfaction score in the general anesthesia group than in the CSEA group. The score was considered good in the general anesthesia group and moderate in the CSEA group. Personnel satisfaction was higher in the patient group that underwent CSEA. In the general anesthesia group, the score was considered to be average. In the CSEA group, the satisfaction score was considered good, with a statistically significant difference (p < 0.05). The anesthesia team’s satisfaction score was moderate, with no significant difference between the CSEA and general anesthesia groups (p > 0.05).

Conclusion

PCNL under CSEA can be performed safely in certain individuals. Different anesthetic techniques may have varied levels of satisfaction among the surgical team.
Melt strain hardening of polymeric systems filled with solid particles: review and supplementary experimental results
Authors: Münstedt Helmut
Published: April 2024

Melt strain hardening is an interesting characteristic property of the elongational flow of polymers. While strain hardening of many unmodified polymer melts has been widely discussed, a comprehensive presentation of the influence of particles on this property is missing. Using literature data and own measurements, the effects of solid particles of various geometries are compared. Micro-sized particles generally reduce melt strain hardening and may even lead to strain thinning. This behavior is postulated to be due to shear flow components around the particles and resulting shear thinning of the polymer matrices that reduces the resistance to flow. More complex is the influence of nano-sized fillers and layered silicate nanoparticles, in particular. Weakly exfoliated particles show effects similar to micro-fillers, but for strongly exfoliated silicates distinct strain hardening is observed that increases with decreasing elongational rate. This behavior is particularly pronounced for polymers modified with maleic anhydrides and thought to be related to electrostatic forces between exfoliated platelets of the silicates and polymer molecules hindering molecular motions.
Association of serum glial fibrillary acidic protein with progression independent of relapse activity in multiple sclerosis
Authors: Rosenstein Igal , Nordin Anna , Sabir Hemin , Malmeström Clas , Blennow Kaj , Axelsson Markus , Novakova Lenka
Published: April 2024

Objective

Insidious disability worsening is a common feature in relapsing–remitting multiple sclerosis (RRMS). Many patients experience progression independent of relapse activity (PIRA) despite being treated with high efficacy disease-modifying therapies. We prospectively investigated associations of body-fluid and imaging biomarkers with PIRA.

Methods

Patients with early RRMS (n = 104) were prospectively included and followed up for 60 months. All patients were newly diagnosed and previously untreated. PIRA was defined using a composite score including the expanded disability status scale, 9-hole peg test, timed 25 foot walk test, and the symbol digit modalities test. Eleven body fluid and imaging biomarkers were determined at baseline and levels of serum neurofilament light (sNfL) and glial fibrillary acidic protein (sGFAP) were also measured annually thereafter. Association of baseline biomarkers with PIRA was investigated in multivariable logistic regression models adjusting for clinical and demographic confounding factors. Longitudinal serum biomarker dynamics were investigated in mixed effects models.

Results

Only sGFAP was significantly higher in PIRA at baseline (median [IQR] 73.9 [60.9–110.1] vs. 60.3 [45.2–79.9], p = 0.01). A cut-off of sGFAP > 65 pg/mL resulted in a sensitivity of 68% and specificity of 61%, to detect patients at higher risk of PIRA. In a multivariable logistic regression, sGFAP > 65 pg/mL was associated with higher odds of developing PIRA (odds ratio 4.3, 95% CI 1.44–12.86, p = 0.009). Repeated measures of sGFAP levels showed that patients with PIRA during follow-up had higher levels of sGFAP along the whole follow-up compared to stable patients (p < 0.001).

Conclusion

Determination of sGFAP at baseline and follow-up may be useful in capturing disability accrual independent of relapse activity in early RRMS.
Asynchronous opinion dynamics in social networks
Authors: Berenbrink Petra , Hoefer Martin , Kaaser Dominik , Lenzner Pascal , Rau Malin , Schmand Daniel
Published: April 2024

Opinion spreading in a society decides the fate of elections, the success of products, and the impact of political or social movements. A prominent model to study opinion formation processes is due to Hegselmann and Krause. It has the distinguishing feature that stable states do not necessarily show consensus, i.e., the population of agents might not agree on the same opinion. We focus on the social variant of the Hegselmann–Krause model. There arenagents, which are connected by a social network. Their opinions evolve in an iterative, asynchronous process, in which agents are activated one after another at random. When activated, an agent adopts the average of the opinions of its neighbors having a similar opinion (where similarity of opinions is defined using a parameter$$\varepsilon $$ε). Thus, the set of influencing neighbors of an agent may change over time. We show that such opinion dynamics are guaranteed to converge for any social network. We provide an upper bound of$${\text {O}}(n|E|^2 (\varepsilon /\delta )^2)$$O(n|E|2(ε/δ)2)on the expected number of opinion updates until convergence to a stable state, where$$|E|$$|E|is the number of edges of the social network, and$$\delta $$δis a parameter of the stability concept. For the complete social network we show a bound of$${\text {O}}(n^3(n^2 + (\varepsilon /\delta )^2))$$O(n3(n2+(ε/δ)2))that represents a major improvement over the previously best upper bound of$${\text {O}}(n^9 (\varepsilon /\delta )^2)$$O(n9(ε/δ)2).
Minimal graphs in Riemannian spaces
Authors: Sauvigny Friedrich
Published: April 2024

In this treatise, we discuss existence and uniqueness questions for parametric minimal surfaces in Riemannian spaces, which represent minimal graphs. We choose the Riemannian metric suitably such that the variational solution of the Riemannian Dirichlet integral under Dirichlet boundary conditions possesses a one-to-one projection onto a plane. At first we concentrate our considerations on existence results for boundary value problems. Then we study uniqueness questions for boundary value problems and for complete minimal graphs. Here we establish curvature estimates for minimal graphs on discs, which imply Bernstein-type results.
Gamma-convergence of a nonlocal perimeter arising in adversarial machine learning
Authors: Bungert Leon , Stinson Kerrek
Published: April 2024

In this paper we prove Gamma-convergence of a nonlocal perimeter of Minkowski type to a local anisotropic perimeter. The nonlocal model describes the regularizing effect of adversarial training in binary classifications. The energy essentially depends on the interaction between two distributions modelling likelihoods for the associated classes. We overcome typical strict regularity assumptions for the distributions by only assuming that they have bounded BV densities. In the natural topology coming from compactness, we prove Gamma-convergence to a weighted perimeter with weight determined by an anisotropic function of the two densities. Despite being local, this sharp interface limit reflects classification stability with respect to adversarial perturbations. We further apply our results to deduce Gamma-convergence of the associated total variations, to study the asymptotics of adversarial training, and to prove Gamma-convergence of graph discretizations for the nonlocal perimeter.
Fractional integration and optimal estimates for elliptic systems
Authors: Hernandez Felipe , Spector Daniel
Published: April 2024

In this paper we give an affirmative answer to the Euclidean analogue of a question of Bourgain and Brezis concerning the optimal Lorentz estimate for a Div–Curl system: If $$F \in L^1(\mathbb {R}^3;\mathbb {R}^3)$$

F
∈

L
1

(

R

3

;

R

3

)

satisfies $$\text {div}F=0$$

div
F
=
0

in the sense of distributions, then the function $$Z=\text {curl} (-\Delta )^{-1} F$$

Z
=
curl

(
-
Δ
)

-
1

F

satisfies $$\begin{aligned} \text {curl } Z&= F \\ \text {div } Z&= 0 \end{aligned}$$

curl

Z

=
F

div

Z

=
0

and there exists a constant $$C>0$$

C
>
0

such that $$\begin{aligned} \Vert Z\Vert _{L^{3/2,1}(\mathbb {R}^3;\mathbb {R}^3)} \le C\Vert F\Vert _{L^{1}(\mathbb {R}^3;\mathbb {R}^3)}. \end{aligned}$$

‖
Z
‖

L

3
/
2
,
1

(

R

3

;

R

3

)

≤
C

‖
F
‖

L
1

(

R

3

;

R

3

)

.

Our proof relies on a new endpoint Hardy–Littlewood–Sobolev inequality for divergence free measures which we obtain via a result of independent interest, an atomic decomposition of such objects.
Is the collateral circulation pattern in the hard palate affected by cleft deformity?
Authors: Shahbazi Arvin , Mueller Andreas A. , Mezey Szilvia , Gschwindt Sebastian , Kiss Tamás , Baksa Gábor , Kisnisci Reha S.
Published: April 2024

Objectives

To evaluate the influence of collateral vascularization on surgical cleft palate closure and deformities.

Materials and methods

Corrosion casting was performed using red-colored acrylic resin in twelve fresh adult cadavers with a normal hard palate. Additionally, white-colored barium sulfate was injected into a fetus with a unilateral complete cleft palate, and layer-by-layer tissue dissection was performed. Both substances were injected into the external carotid arteries. Corrosion casting involved dissolving the soft and hard tissues of the orofacial area utilizing an enzymatic solution.

Results

In normal palates, bilateral intraosseous infraorbital arteries formed a network in the premaxilla with the intraosseous nasopalatine- and greater palatine arteries (GPAs). The perforating GPAs anastomosed with the sphenopalatine artery sub-branches. Bilateral extraosseous GPA anastomoses penetrated the median palatine suture. Complex vascularization in the retrotuberal area was detected. In the cleft zone, anastomoses were omitted, whereas in the non-cleft zone, enlarged GPAs were distributed along the cleft edges and followed the anatomical course anteriorly to initiate the network with facial artery sub-branches.

Conclusions

The anatomical subunits of the palate exhibited distinct anastomosis patterns. Despite omitted anastomoses with collateral circulation in the cleft zone, arteries maintained their anatomical pattern as seen in the normal specimen in the non-cleft zone.

Clinical relevance

Based on the findings in normal- and cleft palates, surgeons may expect developed anastomosis patterns in the non-cleft zone. Due to the lack of microcirculation in the cleft zone, the existent anastomoses should be maintained as much as possible by the surgical technique. This applies anteriorly in the incisive canal territory, alveolar ridges, and posteriorly in the retrotuberal area.
Characterization of speech and language phenotype in the 8p23.1 syndrome
Authors: Karsan Çağdaş , Ocak Feyzanur , Bulut Talat
Published: April 2024

The 8p23.1 duplication syndrome is a rare genetic condition with an estimated prevalence rate of 1 out of 58,000. Although the syndrome was associated with speech and language delays, a comprehensive assessment of speech and language functions has not been undertaken in this population. To address this issue, the present study reports rigorous speech and language, in addition to oral-facial and developmental, assessment of a 50-month-old Turkish-speaking boy who was diagnosed with the 8p23.1 duplication syndrome. Standardized tests of development, articulation and phonology, receptive and expressive language and a language sample analysis were administered to characterize speech and language skills in the patient. The language sample was obtained in an ecologically valid, free play and conversation context. The language sample was then analyzed and compared to a database of age-matched typically-developing children (n = 33) in terms of intelligibility, morphosyntax, semantics/vocabulary, discourse, verbal facility and percentage of errors at word and utterance levels. The results revealed mild to severe problems in articulation and phonology, receptive and expressive language skills, and morphosyntax (mean length of utterance in morphemes). Future research with larger sample sizes and employing detailed speech and language assessment is needed to delineate the speech and language profile in individuals with the 8p23.1 duplication syndrome, which will guide targeted speech and language interventions.
Reduced T2*-weighted placental MRI predicts foetal growth restriction in women with chronic rheumatic disease—a Danish explorative study
Authors: Vestergaard Thea , Julsgaard Mette , Helmig Rikke Bek , Faunø Emilie , Vendelboe Tau , Kelsen Jens , Laurberg Trine Bay , Sørensen Anne , Pedersen Bodil Ginnerup
Published: April 2024

Objectives

Women with chronic rheumatic disease (CRD) are at greater risk of foetal growth restriction than their healthy peers. T2*-weighted magnetic resonance imaging of placenta (T2*P-MRI) is superior to conventional ultrasonography in predicting birth weight and works as a proxy metabolic mirror of the placental function. We aimed to compare T2*P-MRI in pregnant women with CRD and healthy controls. In addition, we aimed to investigate the correlation between T2*P-MRI and birth weight.

Methods

Using a General Electric (GE) 1.5 Tesla, we consecutively performed T2*-weighted placental MRI in 10 women with CRD and 18 healthy controls at gestational week (GW)24 and GW32. We prospectively collected clinical parameters during pregnancy including birth outcome and placental weight.

Results

Women with CRD had significantly lower T2*P-MRI values at GW24 than healthy controls (median T2*(IQR) 92.1 ms (81.6; 122.4) versus 118.6 ms (105.1; 129.1), p = 0.03). T2*P-MRI values at GW24 showed a significant correlation with birth weight, as the T2*P-MRI value was reduced in all four pregnancies complicated by SGA at birth. Three out of four pregnancies complicated by SGA at birth remained undetected by routine antenatal ultrasound.

Conclusion

This study demonstrates reduced T2*P-MRI values and a high proportion of SGA at birth in CRD pregnancies compared to controls, suggesting an increased risk of placental dysfunction in CRD pregnancies. T2*P-MRI may have the potential to focus clinical vigilance by identifying pregnancies at risk of SGA as early as GW24.

Key Points• Placenta-related causes of foetal growth restriction in women with rheumatic disease remain to be investigated.• T2*P-MRI values at gestational week 24 predicted foetuses small for gestational age at birth.• T2*P-MRI may indicate pregnant women with chronic rheumatic disease (CRD) in need of treatment optimization.
Availability of genome-matched therapy based on clinical practice
Authors: Hayashi Naomi , Mori Seiichi , Ohmoto Akihiro , Fukada Ippei , Yamazaki Masumi , Hosonaga Mari , Wang Xiaofei , Ueki Arisa , Kiyotani Kazuma , Tonooka Akiko , Takeuchi Kengo , Takahashi Shunji
Published: April 2024

Background

Comprehensive genomic profiling (CGP) provides new opportunities for patients with advanced cancer to receive genome-matched therapies, but the availability rate of these remains low. We reviewed our CGP cases and suggested possible strategies to improve the current status from a clinical perspective.

Methods

Druggable genomic alterations and barriers to accessing genome-matched therapies were investigated in 653 patients with 30 various types of cancers who underwent CGP.

Results

While the availability rate of genome-matched therapies as a whole was 9.5%, CGP was useful in some cancer types. Patients with thyroid cancer and lung cancer harbored druggable genomic alterations at high rates, while sarcoma rarely harbored these alterations (100%, 76%, and 15.2%, respectively). In contrast, the availability rate of genome-matched therapies was highest in patients with sarcoma and head and neck cancer (HNC) (60% and 40%, respectively). One hundred thirteen patients (63.5%) had multiple barriers to accessing genome-matched therapy. Of 178 patients, 21 patients (11.8%) could not be considered for genome-matched therapies solely because of the deterioration of their performance status.

Conclusion

This study demonstrated the usefulness of CGP for patients with sarcoma and HNC in addition to lung cancer in clinical practice. Performing CGP at the front line has the potential to improve the availability of genome-matched therapy.