bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy field-assisted high-speed dry milling green machining technology for difficult-to-machine metal materials
Authors: Zhang Jin , Huang Xuefeng , Kang Xinzhen , Yi Hao , Wang Qianyue , Cao Huajun
Published: July 2023

Energy field-assisted machining technology has the potential to overcome the limitations of machining difficult-to-machine metal materials, such as poor machinability, low cutting efficiency, and high energy consumption. High-speed dry milling has emerged as a typical green processing technology due to its high processing efficiency and avoidance of cutting fluids. However, the lack of necessary cooling and lubrication in high-speed dry milling makes it difficult to meet the continuous milling requirements for difficult-to-machine metal materials. The introduction of advanced energy-field-assisted green processing technology can improve the machinability of such metallic materials and achieve efficient precision manufacturing, making it a focus of academic and industrial research. In this review, the characteristics and limitations of high-speed dry milling of difficult-to-machine metal materials, including titanium alloys, nickel-based alloys, and high-strength steel, are systematically explored. The laser energy field, ultrasonic energy field, and cryogenic minimum quantity lubrication energy fields are introduced. By analyzing the effects of changing the energy field and cutting parameters on tool wear, chip morphology, cutting force, temperature, and surface quality of the workpiece during milling, the superiority of energy-field-assisted milling of difficult-to-machine metal materials is demonstrated. Finally, the shortcomings and technical challenges of energy-field-assisted milling are summarized in detail, providing feasible ideas for realizing multi-energy field collaborative green machining of difficult-to-machine metal materials in the future.
Selbstfürsorge für Lehrkräfte – Evaluation der Effekte einer Präventions- und Gesundheitsförderungsmaßnahme
Authors: Noichl Teresa , Cramer Malte , Wagner Inga , Dlugosch Gabriele E. , Hosenfeld Ingmar
Published: July 2023

Hintergrund und Fragestellung

Lehrkräfte sind in ihrem Arbeitskontext vielfältigen Belastungen ausgesetzt. Diese können sich negativ auf die körperliche und psychische Befindlichkeit auswirken. Gesundheitsfördermaßnahmen können zur Verringerung von bspw. Stresserleben und Burnout beitragen. Ein bei psychosozialen Fachkräften wirksames Seminar wurde für Lehrkräfte adaptiert. Ziel des Seminars ist es, Selbstfürsorge und Achtsamkeit der Teilnehmenden zu fördern und dadurch möglichen gesundheitlichen Folgen berufsbedingter Belastungen vorzubeugen. Das Online-Seminar wurde zwischen Oktober 2021 und März 2023 auf seine Wirksamkeit hin überprüft.

Studiendesign und Untersuchungsmethoden

Die Studie ist als randomisiertes 2 × 2-faktorielles Wartekontrollgruppenmesswiederholungsdesign mit 3 (Treatment-Gruppe, TG) bzw. 5 (Wartekontrollgruppe, WKG) Messzeitpunkten angelegt. Zentrale abhängige Variablen sind Selbstfürsorge, Achtsamkeit, Stresserleben, emotionale Erschöpfung, Lehrerselbstwirksamkeit und subjektives Wohlbefinden.

Ergebnisse

In beiden Gruppen (TG und WKG) zeigen sich bis ca. 5 Wochen nach der Intervention ein signifikanter Anstieg der Achtsamkeit und Selbstfürsorge und ein signifikanter Rückgang des Stresserlebens und der emotionalen Erschöpfung mit mittleren bis großen Effektstärken. Keine Effekte sind bei der Lehrerselbstwirksamkeit und dem Wohlbefinden zu erkennen. Die Lehrkräfte sind mit der Seminarreihe insgesamt sehr zufrieden und der Nutzen wird als sehr hoch eingestuft.

Diskussion

Eine Verbesserung tritt v. a. direkt im Anschluss an das Treatment auf, die Effekte bleiben über den Zeitraum von ca. 5 Wochen stabil. Das spricht dafür, dass die Lehrkräfte die vermittelten Inhalte gut in den Alltag integrieren konnten.

Schlussfolgerung

Das Training ist eine geeignete Maßnahme, um die psychische Gesundheit von Lehrkräften zu fördern und berufsbedingten Belastungen vorzubeugen.
A priori evaluation of the printability of water-based anode dispersions in inkjet printing
Authors: Kolb Cara Greta , Lehmann Maja , Teixeira Carys-May , Maleksaeedi Saeed , Zaeh Michael Friedrich
Published: July 2023

Inkjet printing represents a disruptive additive manufacturing technology that has emerged as an innovative approach to generate customized lithium-ion batteries by tailored dispersions. However, electrode dispersions cause a complex non-Newtonian behavior which hampers the processability. This paper demonstrates a novel procedure for an a priori evaluation of the printability of aqueous graphite dispersions. Therefore, dispersions with a varying active material content were prepared and the printability was examined through a characterization of the drop formation and the drop deposition behavior. While the drop formation was observed by in-situ monitoring, the drop deposition was analyzed in ex-situ test setups. The rheological properties were systematically determined to calculate nondimensional numbers that describe the dispensing behavior. Consequently, their capability to predict the stability of the drop formation was evaluated. The results revealed that a graphite dispersion with a content of 2 m% allowed for a stable drop formation. No splashing occurred on the substrate during the drop deposition and sufficient wetting can be assumed due to a contact angle of below 90$$^\circ$$

∘

. Conclusions were drawn to further enhance the active material content. Due to the universality of the proposed approach, it is expected to be applicable to different dispersion systems.
Relationship of nematodes in natural and disturbed land with physicochemical properties in Magoebaskloof, Limpopo Province, South Africa
Authors: Shokoohi Ebrahim , Moyo Ngonidzashe , Gouveia Fabio
Published: July 2023

Magoebaskloof is an evergreen mountainous landscape covered with Afromontane forests. During a survey on soil nematode diversity, the soil samples were collected from the rhizosphere of a forest tree (no cultivation over 50 years), grassland, prepared kiwi land, oak tree, kiwifruits trees (37-year-old), and 8-year-old kiwifruit in the Limpopo Province, South Africa. Overall, results showed that a total of 30 nematode genera were found to be associated with the surveyed plant species. The frequency of occurrence showed Ditylenchus (100%), Acrobeloides (100%), and Nanidorus (100%), followed by Meloidogyne (83%) were the most distributed nematodes. The study of the relationship between nematodes with physicochemical properties in the soil using Pearson correlation revealed that clay percentage of the soil has a positive correlation with Pseudacrobeles (r = 0.684), Acrobeloides (r = 0.658) and Meloidogyne (r = 0.668) species. In contrast, clay percentage had a strong negative correlation (r = -0.900) with Filenchus. Soil pH showed no strong correlation with the nematodes. The principal component analysis placed kiwifruits and forest soil in two groups, indicating the biodiversity dynamics among the two locations. In conclusion, forest trees and grasslands showed a high diversity of free-living than disturbed land of kiwifruits. Additionally, plant-parasitic nematodes numbered more in the rhizosphere of kiwifruit trees. Our results suggest that the soil nematodes, especially free-living bacterivores, may mediate the effects of ecosystem disturbance on soil health.
An infinite dimensional version of the intermediate value theorem
Authors: Benevieri Pierluigi , Calamai Alessandro , Furi Massimo , Pera Maria Patrizia
Published: July 2023

Let $$\mathfrak {f}= I-k$$

f
=
I
-
k

be a compact vector field of class $$C^1$$

C
1

on a real Hilbert space $$\mathbb {H}$$
H
. In the spirit of Bolzano’s Theorem on the existence of zeros in a bounded real interval, as well as the extensions due to Cauchy (in $$\mathbb {R}^2$$

R

2

) and Kronecker (in $$\mathbb {R}^k$$

R

k

), we prove an existence result for the zeros of $$\mathfrak {f}$$
f
in the open unit ball $$\mathbb {B}$$
B
of $$\mathbb {H}$$
H
. Similarly to the classical finite dimensional results, the existence of zeros is deduced exclusively from the restriction $$\mathfrak {f}|_\mathbb {S}$$

f
|

S

of $$\mathfrak {f}$$
f
to the boundary $$\mathbb {S}$$
S
of $$\mathbb {B}$$
B
. As an extension of this, but not as a consequence, we obtain as well an Intermediate Value Theorem whose statement needs the topological degree. Such a result implies the following easily comprehensible, nontrivial, generalization of the classical Intermediate Value Theorem: If a half-line with extreme$$q \notin \mathfrak {f}(\mathbb {S})$$

q
∉
f
(
S
)

intersects transversally the function$$\mathfrak {f}|_\mathbb {S}$$

f
|

S

for only one point of  $$\mathbb {S}$$
S
, then any value of the connected component of$$\mathbb {H}{\setminus }\mathfrak {f}(\mathbb {S})$$

H
\
f
(
S
)

containingqis assumed by$$\mathfrak {f}$$
f
in$$\mathbb {B}$$
B
. In particular, such a component is bounded.
MLS-SPH-ALE: A Review of Meshless-FV Methods and a Unifying Formulation for Particle Discretizations
Authors: Eirís Antonio , Ramírez Luis , Couceiro Iván , Fernández-Fidalgo Javier , París José , Nogueira Xesús
Published: July 2023

Mesh-based and particle methods were conceived as two different discretization strategies to solve partial differential equations. In the last two decades computational methods have diversified and a myriad of hybrid formulations that combine elements of these two approaches have been developed to solve Computational fluid dynamics problems. In this work we present a review about the meshless-FV family of methods, an analysis is carried out showing that the MLS-SPH-ALE method can be considered as a general formulation from which a set of particle-based methods can be recovered. Moreover, we show the relations between the MLS-SPH-ALE method and the finite volume method. The MLS-SPH-ALE method is a versatile particle-based method that was developed to circumvent the consistency issues of particle methods caused by the use of the kernel approximation. The MLS-SPH-ALE method is developed from the differential equation in ALE form using the partition unity property which is automatically fulfilled by the Moving Least Squares approximation.
The binding nature of posting PDA1 issued under EU social security Coordination Regulations and the possible role of national courts
Authors: Carrascosa Bermejo Dolores , Molina Millán Juan
Published: July 2023

The EU social security Coordination Regulations envisage a special conflict rule that, under strict conditions, allows posted workers to maintain temporarily the social security insurance of the home Member State. The Portable Document A1 (PDA1), the proof of insurance, is a binding document for the institutions and courts of the host Member State that can only be invalidated or withdrawn by the institutions that issued it or by the corresponding national courts. The case-law of the European Court of Justice has clarified that under certain very specific circumstances a fraudulent foreign PDA1 can be disregarded by a Court, but never invalidated. Communication and collaboration between institutions of the issuing and receiving Member States and the judicial procedures for challenging a foreign PDA1 may need to be enhanced and improved, but the current rules of play respond to the logic of the Coordination Regulations, to sincere cooperation, to legal certainty, and to the uniqueness of the applicable law and the competent jurisdiction. The scarce available data shows that only a few of the three million PDA1s issued each year are being challenged. Given that the main role of the EU legislation is to protect workers, it does not seem logical to change the social security framework of posting, although it can be improved. Mutual trust must be restored.
Role of Circulating Tumor DNA Among Patients with Colorectal Peritoneal Metastases
Authors: Baumgartner Joel M. , Botta Gregory P.
Published: July 2023

Purpose

This was a review of circulating tumor DNA (ctDNA) in patients with peritoneal metastases from colorectal cancer.

Methods

We searched the PubMed database for studies reporting detection of ctDNA in patients with colorectal cancer (CRC) and with peritoneal metastases (PM) from colorectal cancer (CRPM). We extracted data on the population included, number of subjects, study design, type of ctDNA assay used and schedule, and the major findings from these publications.

Results

We identified 13 studies for review investigating ctDNA, using a variety of ctDNA assays, among 1787 patients with CRC without PM, as well as four eligible published and one unpublished (in press) studies, which included 255 patients with PM from any primary site and 61 patients with CRPM. Among the 13 studies investigating ctDNA among CRC without PM, posttreatment surveillance ctDNA was associated with recurrence and was generally more sensitive than imaging or tumor markers. Among the five studies including patients with PM, ctDNA was not universally able to detect the presence of PM, but when present, ctDNA predicted worse outcomes.

Conclusion

Circulating-tumor DNA is a potentially useful surveillance tool for patients with CRC. However, the sensitivity of ctDNA to detect CRPM is variable and warrants further inquiry.
Adolescent Tibial Tubercle Fracture: Review of Outcomes and Complications
Authors: Reyes Chloe Delos , Wu Wei , Pandya Nirav K.
Published: July 2023

Purpose of Review

Fractures of the tibial tubercle are a relatively uncommon injury, representing 3% of all proximal tibia fractures and < 1% of all physeal fractures, primarily seen in the adolescent demographic. While recognition of the injury and its management is being more widely reported in the literature and recognized in the hospital setting, reports of its outcomes and complications have still been limited. This article provides an updated review of the outcomes and complications of tibial tubercle fractures.

Recent Findings

Current research shows both radiographic outcomes, specifically osseous union, and functional outcomes, such as return to play and full knee range of motion, are excellent in patients treated either operatively or nonoperatively. Complication rates overall remain relatively low, with the most common complication being bursitis and hardware prominence and the most common associated injuries being patellar tendon avulsions and meniscus tears.

With appropriate management, tibial tubercle fractures have an excellent overall outcome and a low complication rate. Although complications are uncommon, treating providers should be vigilant and recognize the signs of devastating complications resulting from acute vascular injuries or compartment syndrome. Further research should aim to analyze patients’ experiences and satisfaction following treatment of this injury and examine the long-term functional and patient-reported outcomes.
Modeling the Spatial Distribution of Soil Organic Carbon and Carbon Stocks in the Casanare Flooded Savannas of the Colombian Llanos
Authors: Martín-López Javier M. , Verchot Louis V. , Martius Christopher , da Silva Mayesse
Published: July 2023

Flooded savannas are valuable and extensive ecosystems in South America, but not widely studied. In this study, we quantify the spatial distribution of soil organic carbon (SOC) content and stocks in the Casanare flooded savannas. We sampled 80 sites at two soil-depth intervals (0-10 and 10-30 cm), where SOC values ranged from 0.41% in the surface and 0.23% in the sub-surface of drier soils to over 14.50% and 7.51%, in soils that experienced seasonal flooding. Spatial predictions of SOC were done through two digital soil mapping (DSM) approaches: Expert-Knowledge (EK) and Random-Forest (RF). Although both approaches performed well, EK was slightly superior at predicting SOC. Covariates derived from vegetation cover, topography, and soil properties were identified as key drivers in controlling its distribution. Total SOC stocks were 55.07 Mt with a mean density of 83.1±24.3 t·ha-1 in the first 30 cm of soil, with 12.3% of this located in areas that experience long periods of flooding (semi-seasonal savannas) , which represented only 7.9% of the study area (664,752 ha). Although the study area represents only 15% of the total area of the Casanare department, the intensive pressure of human development could result in the reduction of its SOC stocks and the release of important amounts of greenhouse gases into the atmosphere. At regional level, the impact of a large-scale land use conversions of the flooded Llanos del Orinoco ecosystem area (15 Mha) could transform this area in a future source of important global emissions if correct decisions are not taken regarding the land management of the region.
Diversification for sustainable and resilient agricultural landscape systems
Authors: Reckling Moritz , Watson Christine A. , Whitbread Anthony , Helming Katharina
Published: July 2023

This virtual issue comprises papers that address diversification for providing sustainable solutions at different scales from cropping and grassland to food systems. The authors investigated processes in case studies at the landscape scale where synergies and trade-offs between social and environmental objectives become the most tangible. Contributions from all continents highlighted regional specificities related to diversification and include research from natural and social sciences, with inter- and transdisciplinary approaches including synthesis of knowledge (reviews), empirical studies with experiments as well as assessments with interviews in case studies: Model-based design of crop diversification, the role of digitalization for achieving sustainability in the European context, ecological engineering for rice pest suppression in China, the role of cereal species mixtures in Ethiopian smallholder farmers, diversified planting in arid irrigation areas in northwestern China, integration of legumes in European and Canadian cropping systems, screening of native forage legumes for northern Swedish grassland systems, cropping system diversification of smallholder farmers in south-central Bangladesh, identification of how farmers imagine diversified landscapes in southern Idaho in the US, farm diversification affecting impacts from COVID-19 across Europe, the role of diversified farming in Mato Grosso Brazil, diversification and soil management measures in Germany, value chain formation for the scaling of crop diversification, and the design process with farmers and scientists for the transition toward legume-supported farming in Europe. A key finding from these examples is that agricultural intensification has led to the simplification of cropping systems and landscapes in terms of species diversity and ecosystem function. To instead move towards sustainable transformation, all system levels (i.e. from the plot, farm, landscape, governance and overall food systems) need to interact and reinforce each other for diversification to deliver the desired outcomes.
Probing the intriguing frictional behavior of hydrogels during alternative sliding velocity cycles
Authors: Zhao Yiming , Yi Gang , Cui Jiuyu , Zhao Ziqian , Yan Yonggan , Wei Luxing , Shao Jinlong , Zeng Hongbo , Huang Jun
Published: July 2023

Understanding the friction behavior of hydrogels is critical for the long-term stability of hydrogel-related bioengineering applications. Instead of maintaining a constant sliding velocity, the actual motion of bio-components (e.g., articular cartilage and cornea) often changes abruptly. Therefore, it is important to study the frictional properties of hydrogels serving under various sliding velocities. In this work, an unexpected low friction regime (friction coefficient μ < 10−4 at 1.05×10−3 rad/s) was observed when the polyacrylamide hydrogel was rotated against a glass substrate under alternative sliding velocity cycles. Interestingly, compared with the friction coefficients under constant sliding velocities, the measured μ decreased significantly when the sliding velocity changed abruptly from high speeds (e.g., 105 rad/s) to low speeds (e.g., 1.05×10−3 rad/s). In addition, μ exhibited a downswing trend at low speeds after experiencing more alternative sliding velocity cycles: the measured μ at 1.05 rad/s decreased from 2×10−2 to 3×10−3 after 10 friction cycles. It is found that the combined effect of hydration film and polymer network deformation determines the lubrication and drag reduction of hydrogels when the sliding velocity changes abruptly. The observed extremely low friction during alternative sliding velocity cycles can be applied to reduce friction at contacted interfaces. This work provides new insights into the fundamental understanding of the lubrication behaviors and mechanisms of hydrogels, with useful implications for the hydration lubrication related engineering applications such as artificial cartilage.
The Lund Model
Authors: Andersson Bo
Published: July 2023

The Lund model, inspired by quantum chromodynamics, has provided a promising approach to the dynamics of quark and gluon interactions. Starting with a brief reprise of basic concepts in relativity, quantum mechanics of fields and particle physics, this book discusses: the dynamics of the massless relativistic string; confinement; causality and relativistic covariance; Lund fragmentation processes; QED and QCD Bremsstrahlung; multiplicities and particle-parton distributions. Throughout the book, theory is confronted with current experimental data, and implications for future experiments are also considered. The book also explores the relationships between the Lund model and other models based on field theory (the Schwinger model, S-matrix models, light-cone algebra physics and variations of the parton model), and models based on statistical mechanics (the Feynman-Wilson gas, scaling, iterative cascade models). This title, first published in 1998, has been reissued as an Open Access publication on Cambridge Core.
Spin in Particle Physics
Authors: Leader Elliot
Published: July 2023

Motivated by dramatic developments in the field, this book provides a thorough introduction to spin and its role in elementary particle physics. Starting with a simple pedagogical introduction to spin and its relativistic generalisation, the author avoids the obscurity and impenetrability of traditional treatments of the subject. The book surveys the main theoretical and experimental developments, as well as discussing exciting plans for the future. Emphasis is placed on the importance of spin-dependent measurements in testing QCD and the Standard Model. This book will be of value to graduate students and researchers working in all areas of quantum physics and particularly in elementary particle and high energy physics. It is suitable as a supplementary text for graduate courses in theoretical and experimental particle physics. This title, first published in 2001, has been reissued as an Open Access publication on Cambridge Core.
An Introduction to Regge Theory and High Energy Physics
Authors: Collins P. D. B.
Published: July 2023

This book presents an extended introduction to the theory of hadrons, the elementary particles that occur in the atomic nucleus. The main emphasis is on the theory of the complex angular momentum plane 'Regge theory'. In 1959 Tullio Regge demonstrated that it is useful to regard angular momentum as a complex variable when discussing solutions of the Schrödinger equation for non-relativistic potential scattering. This theory helps to classify the many different particles we know of, to explain the forces between them and to predict the results of high-energy scattering experiments. Regge theory thus serves as a unifying concept drawing together many different features of high-energy physics. This monograph is intended primarily for research students just beginning in particle physics, but experienced practitioners will also find much of interest. Originally published in 1977, this title has been reissued as an Open Access publication on Cambridge Core.
Gauge/String Duality, Hot QCD and Heavy Ion Collisions
Authors: Casalderrey-Solana Jorge , Liu Hong , Mateos David , Rajagopal Krishna , Wiedemann Urs Achim
Published: July 2023

Heavy ion collision experiments recreating the quark-gluon plasma that filled the nascent universe have established that it is a nearly perfect liquid that flows with such minimal dissipation that it cannot be seen as made of particles. String theory provides a powerful toolbox for studying matter with such properties. This book provides a comprehensive introduction to gauge/string duality and its applications to the study of the thermal and transport properties of quark-gluon plasma, the dynamics of how it forms, how it flows, and its response to probes including jets and quarkonium mesons. Calculations are discussed in the context of data from RHIC and LHC and results from finite temperature lattice QCD. This is an ideal reference for students and researchers in string theory, quantum field theory, quantum many-body physics, heavy ion physics and lattice QCD. This title from 2014 has been reissued as an Open Access publication on Cambridge Core.
Predictors of PTSD and Psychological Distress Symptoms of Ukraine Civilians During war
Authors: Eshel Yohanan , Kimhi Shaul , Marciano Hadas , Adini Bruria
Published: July 2023

Objective:

War may raise the level of distress and post-traumatic stress disorder (PTSD). The study explores the extent to which 4 factors determine levels of PTSD and distress symptoms of Ukraine civilians (without developing PTSD) during the current war.

Method:

The data were collected via a Ukrainian internet panel company. 1001 participants responded to a structured online questionnaire. Path analysis was conducted to identify predictive indicators of PTSD scores.

Results:

PTSD symptoms positively correlated with respondents’ level of exposure to the war and their sense of danger, and negatively correlated with well-being, family income, and age. Females scored higher on PTSD symptoms. Path analysis showed that higher exposure to war and higher sense of danger increase PTSD and distress symptoms, whereas higher well-being, higher individual resilience, and being a man, as well as older age decrease their level. Despite the strong effects of the coping suppressing factors, most respondents did not reach the critical level of PTSD or distress symptoms.

Conclusion:

At least 4 positive and negative factors account for people’s coping with stressful experiences: previous traumatic experiences, individual level of pathology, personality attributes, and socio-demographic characteristics. The balance of these factors protects most people from PTSD symptoms despite their being affected by war traumas.
Dispute Over the Status and Use of the Waters of the Silala (Chile v. Bol.) (I.C.J.)
Authors: Sangbana Komlan
Published: July 2023

On December 1, 2022, the International Court of Justice (ICJ) rendered its judgment in the Dispute Concerning the Status and Use of the Waters of the Silala (Chile v. Bolivia). There is no basin agreement governing the Silala, and Chile and Bolivia have ratified neither the 1997 Convention on the Law of Non-Navigational Uses of International Watercourses nor the 1992 Convention on the Protection and Use of Transboundary Watercourses and International Lakes. In the absence of a treaty regime applicable to the waters of the Silala River, the Court had the opportunity in this case to consider the legal framework applicable to international watercourses under customary international law.
Engineering of branched fluidic networks that minimise energy dissipation
Authors: Smink J.S. , Venner C.H. , Visser C.W. , Hagmeijer R.
Published: July 2023

Power minimisation of fluid transport in branched fluidic networks has become of paramount importance for microfluidics, additive manufacturing and hierarchical functional materials. For fully developed laminar flow of Newtonian fluids, Murray's theory provides a solution for the channel and network dimensions that minimise power consumption. However, design and optimisation of networks that transport complex fluids is still challenging. Here, we generalise Murray's theory towards fluid rheologies, including non-Newtonian (power-law) and yield-stress fluids (Bingham, Herschel–Bulkley, Casson). A straightforward graphical approach is presented that provides the optimal radii in a branching network, and the angles between these branches. The wall shear stress is found to be uniform over the entire network, and the velocity profile is self-similar. Furthermore, the effect of non-optimal channel radii on the power consumption of the network is investigated. Finally, examples illustrate how this approach applies to a wide variety of systems.
Influence of heterogeneity or shape on the locomotion of a caged squirmer
Authors: Aymen U. , Palaniappan D. , Demir E. , Nganguia H.
Published: July 2023

The development of novel drug delivery systems, which are revolutionizing modern medicine, is benefiting from studies on microorganisms’ swimming. In this paper we consider a model microorganism (a squirmer) enclosed in a viscous droplet to investigate the effects of medium heterogeneity or geometry on the propulsion speed of the caged squirmer. We first consider the squirmer and droplet to be spherical (no shape effects) and derive exact solutions for the equations governing the problem. For a squirmer with purely tangential surface velocity, the squirmer is always able to move inside the droplet (even when the latter ceases to move as a result of large fluid resistance of the heterogeneous medium). Adding radial modes to the surface velocity, we establish a new condition for the existence of a co-swimming speed (where squirmer and droplet move at the same speed). Next, to probe the effects of geometry on propulsion, we consider the squirmer and droplet to be in Newtonian fluids. For a squirmer with purely tangential surface velocity, numerical simulations reveal a strong dependence of the squirmer's speed on shapes, the size of the droplet and the viscosity contrast. We found that the squirmer speed is largest when the droplet size and squirmer's eccentricity are small, and the viscosity contrast is large. For co-swimming, our results reveal a complex, non-trivial interplay between the various factors that combine to yield the squirmer's propulsion speed. Taken together, our study provides several considerations for the efficient design of future drug delivery systems.
Darwin's doubt or Plantinga's conviction? Some failures in Plantinga's attempt to debunk naturalistic evolution
Authors: Marques Segundo L. H.
Published: July 2023

Darwin's Doubt (DD) – a thesis according to which the probability of the human cognitive mechanism's reliability given non-guided evolution is low – is central to Plantinga's Evolutionary Argument Against Naturalism and his suggestion that the adoption of guided evolution thesis is preferable from a theory choice point of view. In this article I'll argue that there are three fundamental failures in Plantinga's argument. First, I argue that Plantinga's argument for DD is question-begging. Second, I point out that this very same argument is not in accordance with the way the evolutionary scientists usually reason. And finally I argue that the replacement of non-guided by guided evolution violates some reasonable belief-revision procedures in the history of science.
Murphy's Anselmian theism and the problem of evil
Authors: Wilson Luke
Published: July 2023

Mark Murphy has recently defended a novel account of divine agency on which God would have very minimal requiring reasons and a wide range of merely justified reasons. This account grounds his response to the problem of evil. If God would not have requiring reasons to promote the well-being of creatures, Murphy argues, then the evil we observe would not count as evidence against theism. I argue that Murphy's conclusion, if successful in undermining the problem of evil, also undermines probabilistic arguments for theism. However, there is good reason to resist his conclusion. Even if God does not have requiring reasons, but merely has justifying reasons, to promote creaturely well-being, God may nevertheless have most motivating reason to do so, and this would be enough to predict divine action, at least given Murphy's further assumption that God is perfectly free. It does not follow from the rational permissibility of God's Φ-ing that it is possible for God to Φ.
Becoming the Muʿallim: how tradition and innovation made a Nahḍa icon
Authors: Edwards Anthony
Published: July 2023

One cannot speak of the nineteenth-century Beirut Nahḍa and not mention Muʿallim Buṭrus al-Bustānī (1819–83). This article examines how al-Bustānī utilized the Arabic oratorical tradition and the innovative medium of print to create the Muʿallim brand. The first section analyses his Khuṭba fī Ādāb al-ʿArab (An Oration on the Culture of the Arabs, 1859) to illustrate how he operationalized the Arabic rhetorical style to position himself as an eloquent public intellectual. This article next discusses how he built parts of this lecture on sariqāt (literary thefts/legitimate borrowings) from his contemporaries and participated in the collective practice of knowledge production. Lastly, al-Bustānī's advertising tactics in print to promote his public persona are explored. This article demonstrates that al-Bustānī successfully established himself as the Muʿallim by coupling the enduring cultural power of Arabic oration with the modern might of print.
Poliovirus outbreak in New York State, August 2022: qualitative assessment of immediate public health responses and priorities for improving vaccine coverage
Authors: Kasstan Ben , Mounier-Jack Sandra , Chantler Tracey , Masters Nina , Flores Stephen A , Stokley Shannon , Meek Haillie , Easton Delia , De Luna-Evans Tatiana , Souto Maria , Punjabi Chitra , Ruppert Patricia Schnabel , Rosenberg Eli , Routh Janell
Published: July 2023

In 2022, a case of paralysis was reported in an unvaccinated adult in Rockland County (RC), New York. Genetically linked detections of vaccine-derived poliovirus type 2 (VDPV2) were reported in multiple New York counties, England, Israel, and Canada. The aims of this qualitative study were to: i) review immediate public health responses in New York to assess the challenges in addressing gaps in vaccination coverage; ii) inform a longer-term strategy to improving vaccination coverage in under-vaccinated communities, and iii) collect data to support comparative evaluations of transnational poliovirus outbreaks. Twenty-three semi-structured interviews were conducted with public health professionals, healthcare professionals, and community partners. Results indicate that i) addressing suboptimal vaccination coverage in RC remains a significant challenge after recent disease outbreaks; ii) the poliovirus outbreak was not unexpected and effort should be invested to engage mothers, the key decision-makers on childhood vaccination; iii) healthcare providers (especially paediatricians) received technical support during the outbreak, and may require resources and guidance to effectively contribute to longer-term vaccine engagement strategies; vi) data systems strengthening is required to help track under-vaccinated children. Public health departments should prioritize long-term investments in appropriate communication strategies, countering misinformation, and promoting the importance of the routine immunization schedule.
Stress system concordance as a predictor of longitudinal patterns of resilience in adolescence
Authors: Wiglesworth Andrea , Butts Jessica , Carosella Katherine A. , Mirza Salahudeen , Papke Victoria , Bendezú Jason José , Klimes-Dougan Bonnie , Cullen Kathryn R.
Published: July 2023

Resilience promotes positive adaptation to challenges and may facilitate recovery for adolescents experiencing psychopathology. This work examined concordance across the experience, expression, and physiological response to stress as a protective factor that may predict longitudinal patterns of psychopathology and well-being that mark resilience. Adolescents aged 14–17 at recruitment (oversampled for histories of non-suicidal self-injury; NSSI) were part of a three-wave (T1, T2, T3) longitudinal study. Multi-trajectory modeling produced four distinct profiles of stress experience, expression, and physiology at T1 (High-High-High, Low-Low-Low, High-Low-Moderate, and High-High-Low, respectively). Linear mixed-effect regressions modeled whether the profiles predicted depressive symptoms, suicide ideation, NSSI engagement, positive affect, satisfaction with life, and self-worth over time. Broadly, concordant stress response profiles (Low-Low-Low, High-High-High) were associated with resilient-like patterns of psychopathology and well-being over time. Adolescents with a concordant High-High-High stress response profile showed a trend of greater reduction in depressive symptoms (B = 0.71, p = 0.052), as well as increased global self-worth (B = –0.88, p = 0.055), from T2 to T3 compared to the discordant High-High-Low profile. Concordance across multi-level stress responses may be protective and promote future resilience, whereas blunted physiological responses in the presence of high perceived and expressed stress may indicate poorer outcomes over time.
Assessing enrollment of eligible infants in the national pediatric cardiology quality improvement collaborative (NPC-QIC) through linkage to the pediatric cardiac critical care consortium (PC4) registry
Authors: Bates Katherine E. , Donohue Janet , Zhang Wenying , Mikesell Katherine , Anderson Jeffrey B. , Bingler Michael , Brown David W. , Gaies Michael G. , Ghanayem Nancy , Lambert Linda M. , Pasquali Sara K. , Schidlow David , Vergales Jeffrey , Schumacher Kurt R.
Published: July 2023

Background:

The National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) lacks a rigorous enrollment audit process, unlike other collaborative networks. Most centers require individual families to consent to participate. It is unknown whether there is variation across centers or biases in enrollment.

Methods:

We used the Pediatric Cardiac Critical Care Consortium (PC4) registry to assess enrollment rates in NPC-QIC for those centers participating in both registries using indirect identifiers (date of birth, date of admission, gender, and center) to match patient records. All infants born 1/1/2018–12/31/2020 and admitted 30 days of life were eligible. In PC4, all infants with a fundamental diagnosis of hypoplastic left heart or variant or who underwent a surgical or hybrid Norwood or variant were eligible. Standard descriptive statistics were used to describe the cohort and center match rates were plotted on a funnel chart.

Results:

Of 898 eligible NPC-QIC patients, 841 were linked to 1,114 eligible PC4 patients (match rate 75.5%) in 32 centers. Match rates were lower in patients of Hispanic/Latino ethnicity (66.1%, p = 0.005), and those with any specified chromosomal abnormality (57.4%, p = 0.002), noncardiac abnormality (67.8%, p = 0.005), or any specified syndrome (66.5%, p = 0.001). Match rates were lower for patients who transferred to another hospital or died prior to discharge. Match rates varied from 0 to 100% across centers.

Conclusions:

It is feasible to match patients between the NPC-QIC and PC4 registries. Variation in match rates suggests opportunities for improvement in NPC-QIC patient enrollment.
On Mexican poverty-trap regimes and struggling to escape them
Authors: Sanchez Carrera Edgar J. , Risso Wiston Adrián
Published: July 2023

This paper deals with the phenomenon of poverty-trap regimes in Mexico, that is, self-reinforcing mechanisms in which municipalities which start poor remain poor. We develop a coordination game of poverty traps driven by strategic interactions of economic agents: people choose to complete or not their education levels since it might be excessively costly and unprofitable. A one-shot game is constructed and then converted into a system of differential equations in which strategies that perform relatively better become more abundant in the population. Applying evolutionary games and symbolic-regimes dynamics (nonparametric and nonlinear techniques), we show that Mexican regions are in poverty-trap regimes (stable and dynamically evolving low-level equilibria) characterized by incomplete education and low income since initial conditions (education and income per capita) are such (very precarious) that poverty is the stable steady-state situation. We examine scenarios to show that to overcome the high-poverty regime by the year 2030, it is necessary to reduce incomplete education by 10% in the 5-year periods 2020–2025 and 2025–2030 and increase per-capita income by 10% in both periods.
The color purple: Purple urine bag syndrome: Identifying the phenomenon to ease unnecessary anxiety, fear, and distress
Authors: Julião Miguel , Cruz Mário
Published: July 2023

Objectives

Purple urine bag syndrome (PUBS) is a condition that causes an intense purple discoloration of the urine, predominately in frail, dependent, and bedridden persons who are chronically catheterized and have urinary tract infections. Despite being considered a benign syndrome, PUBS can cause great anxiety, fear, and distress in health professionals, chronically ill persons, and caregivers or family members who provide care.

Methods

We report the case of a 98-year-old institutionalized woman with Alzheimer’s dementia with a long-term urinary catheter who developed PUBS.

Results

Although alarming and distressing for the resident and the health-care team, PUBS was resolved by treating the underlying urinary tract infection and applying good genital hygiene and catheter replacement.

Significance of results

Identifying PUBS and its clinical features and management proved to be significantly helpful in ameliorating the anxiety, fear, and distress around the phenomenon.
Disrespectful and inadequate palliative care to lesbian, gay, and bisexual patients
Authors: Berkman Cathy , Stein Gary L. , Godfrey David , Javier Noelle Marie , Maingi Shail , O’Mahony Sean
Published: July 2023

Objectives

The study aims to describe inadequate, disrespectful, and abusive palliative and hospice care received by lesbian, gay, and bisexual (LGB) patients and their spouses/partners due to their sexual orientation or gender identity.

Methods

A national sample of 865 healthcare professionals recruited from palliative and hospice care professional organizations completed an online survey. Respondents were asked to describe their observations of inadequate, disrespectful, or abusive care to LGB patients and their spouses/partners.

Results

There were 15.6% who reported observing disrespectful care to LGB patients, 7.3% observed inadequate care, and 1.6% observed abusive care; 43% reported discriminatory care toward the spouses/partners. Disrespectful care to LGB patients included insensitive and judgmental attitudes and behaviors, gossip and ridicule, and disrespect of the spouse/partner. Inadequate care included denial of care; care that was delayed incomplete, or rushed; dismissive or antagonistic treatment; privacy and confidentiality violations; and dismissive treatment of the spouse/partner.

Significance of results

These findings provide evidence of discrimination faced by LGB patients and partners while receiving care for serious illness. Hospice and palliative care programs should promote respectful, inclusive, and affirming care for the lesbian, gay, bisexual, transgender, and queer (LGBTQ) community, including policies and practices that are welcoming and supportive to both employees and patients. Staff at all levels should be trained to create safe and respectful environments for LGBTQ patients and their families.
River Geomorphology Affects Biogeochemical Responses to Hydrologic Events in a Large River Ecosystem
Authors: Waite T. , Jankowski K. J. , Bruesewitz D. A. , Van Appledorn M. , Johnston M. , Houser J. N. , Baumann D. A. , Bennie B.
Published: July 2023

Shifts in the frequency and intensity of high discharge events due to climate change may have important consequences for the hydrology and biogeochemistry of rivers. However, our understanding of event‐scale biogeochemical dynamics in large rivers lags that of small streams. To fill this gap, we used high‐frequency sensor data collected during four consecutive summers from a main channel and backwater site of the Upper Mississippi River. We identified high discharge events and calculated event concentration‐discharge responses for both physical‐chemical (nitrate, turbidity, and fluorescent dissolved organic matter) and biological (chlorophyll‐a and cyanobacteria) constituents using metrics of hysteresis and slope. We found a range of responses across events, particularly for nitrate. Although fluorescent dissolved organic matter (FDOM) and turbidity exhibited more consistent responses across events, contrasting hysteresis metrics indicated that FDOM was flushed to the river from more distant sources than turbidity. Biological responses (chlorophyll a and cyanobacteria) differed more between sites than physical and chemical constituents. Lastly, we found that the event characteristics best explaining concentration responses differed between sites, with event magnitude more frequently related to responses in the main channel, and antecedent wetness conditions associated with response variation in the backwater. Our results indicate that event responses in large rivers are distinct across the diverse habitats and biogeochemical components of a large floodplain river, which has implications for local and downstream ecosystems as the climate shifts.
Explaining the Statistical Properties of Salt Intrusion in Estuaries Using a Stochastic Dynamical Modeling Approach
Authors: Dijkstra Henk A. , Biemond Bouke , Lee Jiyong , de Swart Huib E.
Published: July 2023

Determining the statistical properties of salt intrusion in estuaries on sub‐tidal time scales is a substantial challenge in environmental modeling. To study these properties, we here extend an idealized deterministic salt intrusion model to a stochastic one by including a stochastic model of the river discharge. In the river discharge model, two types of stochastic forcing are used: one independent (additive noise) and one dependent (multiplicative noise) on the river discharge state. Each type of forcing results in a non‐Gaussian response in the salt intrusion length, which we consider here as the distance of the 2 psu isohaline contour to the estuary mouth. The salt intrusion model including both types of stochastic forcing in the river discharge provides a satisfactory explanation of the multi‐year statistics of observed salt intrusion lengths in the San Francisco Bay estuary, in particular for the skewness of its probability density function.