bluuebunny/crossref_metadata_2025 huggingface dataset:
Polarization and frequency multiplexed multi-channel focusing terahertz vortex with a birefringent dielectric metasurface
Authors: Ren Zhi , Zhao Yinghui , Wang Wanqing , Yao Hongjia , Ren Guanhua , Li Songtao , Wang Ruoxing
Published: April 2024

We propose an approach to generate polarization and frequency multiplexed focusing vortex beams using a birefringent dielectric metasurface in terahertz (THz) range. The designed metadevice consists of Si nanopillars with different sizes. The transmission efficiency of each unit cell under orthogonal polarized illumination can exceed 70% at both operating frequencies 1 THz and 1.2 THz. Combining the functions of beam deflection, focusing, and vortex beam generation in the interference holography design strategy, polarization and frequency multiplexed multi-channel focusing THz vortex beams with different topological charges and generation positions can be achieved, which can greatly improve the transmission capacity of THz communications. Combining its compact and efficient features with multiplexing methods, our designed metadevice has enormous potential for application in THz vortex generation and information processing.
Tailoring the optical properties of dye–polymer composite films based on polyvinyl alcohol doped with phenol red toward flexible optoelectronic applications
Authors: Al-Muntaser A A , Althobiti Randa A , Al Naim Abdullah F , Alzahrani Eman , Tarabiah A E
Published: April 2024

The composite films of polyvinyl alcohol (PVA) incorporating varying concentrations of phenol red (PR) dye were fabricated using the solution casting method. Structural characteristics of the prepared films were explored through XRD and FTIR spectroscopy analyses. The inclusion of PR dye within the PVA matrix induced cross-linking, enhancing the amorphous nature of the doped PVA samples, as evidenced by XRD patterns. In the presence of PR dopants, the FTIR peaks for PVA exhibited altered intensities and increased width, indicating physical interactions between the functional groups of PVA and PR dopants. The impact of PR additives on the optical properties of PVA was investigated across the spectral range of 190–2500 nm. The PVA/phenol red composite demonstrated enhanced UV blocking in the 190–400 nm wavelength range, rendering it suitable for applications such as UV notch filters, including laser blocking filters. The indirect and direct optical band-gaps of PVA polymer films were reduced from 5.20 eV and 5.78 eV to 4.30 eV and 5.28 eV, respectively, with an increase in the PR filling ratio from 0 wt% to 1.8 wt%. The dispersion region of the refractive index was analyzed using the single oscillator model (Wemple-DiDomenico). Calculation and discussion of values such as dispersion and oscillation energies (Ed and Eo), permittivity at infinite frequency (ε
∞), and lattice contribution to the dielectric function (ε
L) of PVA/PR composite films were conducted. These advancements position PVA/PR composite films for potential applications in flexible optoelectronic devices, including light-emitting diodes and photodetectors.
Efficient doping of functionalized graphene and h-BN by molecular adsorption
Authors: Fu Shiyang , Yang Yuhan , Zhang Mai , Gao Nan , Wang Qiliang , Li Hongdong
Published: April 2024

In this work, we investigate the structural and electronic properties of molecular acceptors and donors adsorbed on H/F-functionalized graphene and h-BN by using first principles calculation. Graphane adsorbed with acceptors show p-type doping features, and fluorographene with donors are n-type doping. On the other hand, both H- and F-functionalized BN adsorbed systems exhibit n-type doping. The different doping characteristics depend on the relative energy level alignment of the molecules and substrates, which determines the electron transfer direction. In addition, the bands of adatoms are close to the band edges of substrates near Fermi level (0.0004–0.113 eV), denoting the efficient doping for H/F-functionalized graphene and h-BN. These results provide important indications for designing novel two-dimensional materials with suitable doped characteristics for opto-electronics applications.
Thermal analysis of black hole in de Rham–Gabadadze–Tolley massive gravity in barrow entropy framework
Authors: Yasir Muhammad , Xia Tiecheng , Upadhyay Sudhaker
Published: April 2024

This study examines a recently hypothesized black hole solution in de Rham–Gabadadze–Tolley massive gravity. Firstly, we consider the negative cosmological constant as a thermodynamic pressure. We extract the thermodynamical properties such as Hawking temperature, heat capacity and Gibbs free energy using the barrow entropy. We also obtain a new pressure associated to the perfect fluid dark matter and discuss the first-order van der Waals-like phase transition. This black hole’s stability is investigated through specific heat and Gibbs free energy. Also, we analyze the thermodynamic curvatures behavior of black hole through geometry methods (Weinhold, Ruppeiner, Hendi-Panahiyah-Eslam-Momennia (HPEM), and geometrothermodynamics (GTD)).
Analysis of the Characteristics of Rice Husk and Pinecone Bio-briquettes with Tapioca Flour Adhesive
Authors: Suanggana D , Qalbi AM C , Fijatmoko F , Duma GA
Published: April 2024

Making bio briquettes is one way to produce environmentally friendly and renewable energy. Biobriquette raw materials can come from rice husk and pinecone waste, often found in Indonesia. This study aims to determine the characteristics of bio briquettes from a mixture of rice husks and pinecones with tapioca flour adhesive, including moisture content and calorific value, and to determine the characteristics of the best mixture based on SNI 01-6235-2000 standards. This study uses an experimental method where rice husks and pinecones are first converted into charcoal by a carbonization process and mixed with an adhesive from tapioca flour. Variations of husk and pinecone mixture used were SP1 (100% rice husk), SP2 (75%:25%), SP3 (50%:50%), SP4 (25%:75%, and SP5 (100% pinecones). Based on the results of the research on the characteristics of rice husk and pinecones bio briquettes with tapioca flour adhesive for the moisture content of SP1 28.42%, SP2 28.8%, SP3 27.07%, SP4 26.99%, and SP5 27.84%, while the calorific value obtained, is SP1 2745.13 cal/g, SP2 4302.73 cal/g, SP3 4777.10 cal/g, SP4 5485.93 cal/g, SP5 6152.83 cal/g. However, according to SNI, the bio briquettes’ moisture content characteristics for each variation have not met the standard. It has met the SNI standard when viewed from the calorific value of the SP4 and SP5 variations.
An Effect of Gap Ratios at Four Circular Cylinders in a Staggered Configuration Near a Plane Wall
Authors: Wailanduw A G , Yuwono T
Published: April 2024

The flow that crosses the arrangement of four circular cylinders will form a certain flow pattern according to the geometry of the body contour, the distance between the cylinders, and the flow orientation (α), and generated aerodynamic forces, such as lift force, drag force, as well as induced vibration on the body. The force coefficients on four circular cylinders in an equispaced arrangement with a staggered configuration located near a plane wall were calculated through the pressure distributions measurement. The pressure distributions on each cylinder surface and the plane wall were measured for various gap ratio values of G/D= 0.0 and 0.2 (G, the gap between cylinder to the plane wall; D, diameter) and L/D= 2.7 (L, gap spacing between cylinders) in a uniform flow at a Reynolds Number of 1.743 x 104. The results show that the drag and lift coefficients on the cylinders depend on the gap ratio value of G/D. The drag coefficient decreases, when the amount of G/D increases, especially on the upstream cylinders. The lift coefficient on the upper-downstream cylinders has a significant value more than other cylinders at a small spacing ratio.
Social Parameter’s Role in BEM-PSO-Based Inverse Analysis for Locating Corrosion of Reinforced Concrete
Authors: Fonna S , Ibrahim I B M , Julianda A , Kurniawan R , Huzni S , Ariffin A K
Published: April 2024

The objective of this research is to investigate the effect of social parameter on the performance of boundary element inverse analysis (BEIA) to determine the location of reinforcing steel corrosion in concrete. BEIA was constructed by integrating the Boundary Element Method (BEM) and Particle Swarm Optimization (PSO) (PSO). BEM was used to calculate the corrosion potential on the whole surface of reinforced concrete. The cost function for detecting corrosion of reinforcing steel in concrete was evaluated using PSO. BEIA was conducted with 15 electrical potential data on the surface of reinforced concrete as a reference, such as from half-cell potential measurement. Numerical simulations of reinforced concrete with a single reinforcement reveal a difference in the speed of BEIA in locating corrosion sites. The higher the social parameter value, the faster the particles tend to migrate. However, if the parameter value is too high, the number of iterations required for the particles to converge increases, which has a negative effect on locating the corrosion point. Consequently, the variation of the social parameter affects the performance of BEIA in detecting the location of corrosion in reinforced concrete.
Cell Design in Crash Box to Increase the Energy Absorption Efficiency
Authors: Harbelubun M M , Hardi W , Umar K
Published: April 2024

Researchers have completed many methods to increase the ability of thin tubes to absorb impact energy. Various methods are proposed covering the use of different materials, including new designs, which are expected to improve their performance. This study aims to obtain an Impact Energy Absorber (IEA), which has a low peak impact force and has better crash force efficiency (CFE), energy absorption (EA), and specific energy absorption (SEA). This study made a design change from an empty square tube to a square tube with a cell structure inside. A thin-walled box in the form of a box with a base size of 50 mm x 50 mm without a lid and a height of 150 mm with a thickness of 2 mm was used in this study. A load strikes the tube from the axial direction with a speed of 100 m/s while the other end is supported by fixed support. Deformation, impact force, and absorbed energy were recorded in all types of specimens. The results showed an increase in the reaction force between boxes that were given cells compared to empty ones. While the addition of cell variations from 1 to 2 did not experience a significant change in the impact force. The maximum deformation decreases with the number of cells, while the energy absorbed per unit length increases. The deformation pattern changes due to cells in the box because there is an obstacle when it is deformed towards the outside of the tube. The results of this study are considered in manufacturing high-speed crash boxes.
Development of Two Wheel Drive Electric Bikes for Extreme Road and A Long-Range Capabilities
Authors: Candra S , Tjandra S , Soesanti A , Susanto H , Prihartono T W
Published: April 2024

This paper aims to develop the electric bicycle by using a two-wheel drive that has a long range of use. This development is motivated by many extreme roads and the absence of a charging station except in the user’s own house. A folding bicycle type bicycle for adults with 16-inch wheels was used in this study. The two-wheel drive can be adjusted using the driving motor to be more flexible and adapt to road conditions, although the motor power used is small, 350-Watt 24 Volt for one wheel. The battery capacity used is quite large for the range quite far away, which is 24 volts 80 Amps, and the charging time is about 2 hours. The placement of the battery has calculated the center of gravity and balance of the bike. Results show that this electric bicycle can be used for slippery road conditions and slopes of not more than 1A maximum speed of the bicycle can reach up to 30 km/hour, on flat road conditions. Likewise, the bicycle’s range for a full charge is around 220-260 km, with an average speed of 15-16 km/hour. Two drives can be implemented independently, adjusting the running conditions by moving the drive motor selection button. For extreme conditions, it is recommended to use two electric motors.
Commissioning of the test system for PS and 2S hybrids for the Phase-2 Upgrade of
the CMS Outer Tracker
Authors: Szydlik P. , Allongue B. , Blanchot G. , Carnesecchi R. , Kovacs M. , Mateos Dominguez I. , Schleidweiler K. , Zografos A. ,   the CMS collaboration
Published: April 2024

The Phase-2 Upgrade [1] of the CMS Outer Tracker [2] requires the production of 7608 Strip-Strip (2S) and 5592 Pixel-Strip (PS) modules, altogether incorporating 45 192 hybrid circuits of 15 design variants. The module design makes the potential repairs impractical; therefore, performing production-scale testing of the hybrids is essential. Accordingly, a scalable, crate-based test system was designed and manufactured, allowing for parallel, high-throughput testing. To reproduce the operating conditions, the system was integrated within a climate chamber, which required the development of a remote control interface and the calibration of thermal cycles. The results and lessons learned from the test system integration and commissioning will be presented.
CaloClouds II: ultra-fast geometry-independent highly-granular calorimeter simulation
Authors: Buhmann Erik , Gaede Frank , Kasieczka Gregor , Korol Anatolii , Korcari William , Krüger Katja , McKeown Peter
Published: April 2024

Fast simulation of the energy depositions in high-granular
detectors is needed for future collider experiments at
ever-increasing luminosities. Generative machine learning (ML)
models have been shown to speed up and augment the traditional
simulation chain in physics analysis. However, the majority of
previous efforts were limited to models relying on fixed, regular
detector readout geometries. A major advancement is the recently
introduced CaloClouds model, a geometry-independent diffusion
model, which generates calorimeter showers as point clouds for the
electromagnetic calorimeter of the envisioned International Large
Detector (ILD).

In this work, we introduce CaloClouds II which features a
number of key improvements. This includes continuous time
score-based modelling, which allows for a 25-step sampling with
comparable fidelity to CaloClouds while yielding a
6× speed-up over Geant4 on a single CPU (5×
over CaloClouds). We further distill the diffusion model
into a consistency model allowing for accurate sampling in a single
step and resulting in a 46× speed-up over Geant4
(37× over CaloClouds). This constitutes the first
application of consistency distillation for the generation of
calorimeter showers.
High-precision 3D printing of multi-branch vascular scaffold with plasticized PLCL thermoplastic elastomer
Authors: Han Yunda , Wang Heran , Guan Yuheng , Li Song , Yuan Zewei , Lu Lihua , Zheng Xiongfei
Published: April 2024

Three-dimensional (3D) printing has emerged as a transformative technology for tissue engineering, enabling the production of structures that closely emulate the intricate architecture and mechanical properties of native biological tissues. However, the fabrication of complex microstructures with high accuracy using biocompatible, degradable thermoplastic elastomers poses significant technical obstacles. This is primarily due to the inherent soft-matter nature of such materials, which complicates real-time control of micro-squeezing, resulting in low fidelity or even failure. In this study, we employ Poly (L-lactide-co-ϵ-caprolactone) (PLCL) as a model material and introduce a novel framework for high-precision 3D printing based on the material plasticization process. This approach significantly enhances the dynamic responsiveness of the start-stop transition during printing, thereby reducing harmful errors by up to 93%. Leveraging this enhanced material, we have efficiently fabricated arrays of multi-branched vascular scaffolds that exhibit exceptional morphological fidelity and possess elastic moduli that faithfully approximate the physiological modulus spectrum of native blood vessels, ranging from 2.5 to 45 MPa. The methodology we propose for the compatibilization and modification of elastomeric materials addresses the challenge of real-time precision control, representing a significant advancement in the domain of melt polymer 3D printing. This innovation holds considerable promise for the creation of detailed multi-branch vascular scaffolds and other sophisticated organotypic structures critical to advancing tissue engineering and regenerative medicine.
Recent trends in bone tissue engineering: a review of materials, methods, and structures
Authors: Moghaddam Armaghan , Bahrami Mehran , Mirzadeh Motahareh , Khatami Mehrdad , Simorgh Sara , Chimehrad Mohammadreza , Kruppke Benjamin , Bagher Zohreh , Mehrabani Davood , Khonakdar Hossein Ali
Published: April 2024

Bone tissue engineering (BTE) provides the treatment possibility for segmental long bone defects that are currently an orthopedic dilemma. This review explains different strategies, from biological, material, and preparation points of view, such as using different stem cells, ceramics, and metals, and their corresponding properties for BTE applications. In addition, factors such as porosity, surface chemistry, hydrophilicity and degradation behavior that affect scaffold success are introduced. Besides, the most widely used production methods that result in porous materials are discussed. Gene delivery and secretome-based therapies are also introduced as a new generation of therapies. This review outlines the positive results and important limitations remaining in the clinical application of novel BTE materials and methods for segmental defects.
Exploring macroeconomic models in the water, energy, food, and ecosystem (WEFE) field: a comprehensive review
Authors: Castelli Chiara , Castellini Marta , Gusperti Camilla , Gaia Romani Ilenia , Ciola Emanuele , Vergalli Sergio
Published: April 2024

This study conducts a comprehensive review of macroeconomic models within the Water, Energy, Food, and Ecosystem (WEFE) nexus, considering four different approaches: computable general equilibrium (CGE) models, integrated assessment models (IAMs), agent-based models (ABMs), and dynamic stochastic general equilibrium (DSGE) models. Specifically, we examine how macroeconomic models represent not only the WEFE nexus as a whole but also its individual components and their combinations. Spanning a collection of 77 papers published in the last 20 years, this review underscores the prevalence of CGE models and IAMs, followed by ABMs, as dominant avenues of research within this field. CGE models frequently investigate interconnections between pairs of WEFE elements, while IAMs focus on the whole nexus. At the same time, ABMs do not exhibit a clear pattern, whereas DSGE models predominantly concentrate on the energy component alone. Overall, our findings indicate that the development of DSGE models and ABMs is still in its early stages. DSGE models potentially allow the analysis of uncertainty and risk in this field, while ABMs might offer new insights into the complex interactions between natural and human systems but still lack a common framework.
Stability analysis of uncertain simple pendulum equation
*
Authors: Qiu Xiaoyue , Liu Liying
Published: April 2024

The law of motion of a simple pendulum system is described by an uncertain simple pendulum equation which is a second-order uncertain differential equation driven by Liu process (LP). The stability of a simple pendulum system refers to whether the system tends to the equilibrium state under small perturbation. In order to discuss the sensitivity of the uncertain simple pendulum equation to the perturbation in the initial state, we give the concept of many kinds of stability of the uncertain simple pendulum equation, including almost deterministic stability, distributional stability and exponential stability. And, the sufficient conditions of almost deterministic stability, distributional stability and exponential stability of the uncertain simple pendulum equation are proved respectively.
Super-polynomial accuracy of multidimensional randomized nets using the median-of-means
Authors: Pan Zexin , Owen Art
Published: April 2024

We study approximate integration of a function

f
f

over

[
0
,
1

]
s

[0,1]^s

based on taking the median of

2
r
−
1

2r-1

integral estimates derived from independently randomized

(
t
,
m
,
s
)

(t,m,s)

-nets in base

2
2

. The nets are randomized by Matousek’s random linear scramble with a random digital shift. If

f
f

is analytic over

[
0
,
1

]
s

[0,1]^s

, then the probability that any one randomized net’s estimate has an error larger than

2

−
c

m
2

/

s

2^{-cm^2/s}

times a quantity depending on

f
f

is

O
(
1

/

m

)

O(1/\sqrt {m})

for any

c
>
3
log
⁡
(
2
)

/

π
2

≈
0.21

c>3\log (2)/\pi ^2\approx 0.21

. As a result, the median of the distribution of these scrambled nets has an error that is

O
(

n

−
c
log
⁡
(
n
)

/

s

)

O(n^{-c\log (n)/s})

for

n
=

2
m

n=2^m

function evaluations. The sample median of

2
r
−
1

2r-1

independent draws attains this rate too, so long as

r

/

m
2

r/m^2

is bounded away from zero as

m
→
∞

m\to \infty

. We include results for finite precision estimates and some nonasymptotic comparisons to taking the mean of

2
r
−
1

2r-1

independent draws.
Stretched sapwood, ultra-widening permeability and ditching da Vinci: revising models of plant form and function
Authors: Anfodillo Tommaso , Olson Mark E
Published: April 2024

Background

The mechanisms leading to dieback and death of trees under drought remain unclear. To gain an understanding of these mechanisms, addressing major empirical gaps regarding tree structure–function relations remains essential.

Scope

We give reasons to think that a central factor shaping plant form and function is selection simultaneously favouring constant leaf-specific conductance with height growth and isometric (1:1) scaling between leaf area and the volume of metabolically active sink tissues (‘sapwood’). Sapwood volume–leaf area isometry implies that per-leaf area sapwood volumes become transversely narrower with height growth; we call this ‘stretching’. Stretching means that selection must favour increases in permeability above and beyond that afforded by tip-to-base conduit widening ("ultra-widening permeability"), via fewer and wider vessels or tracheids with larger pits or larger margo openings. Leaf area–metabolically active sink tissue isometry would mean that it is unlikely that larger trees die during drought because of carbon starvation due to greater sink–source relationships as compared to shorter plants. Instead, an increase in permeability is most plausibly associated with greater risk of embolism, and this seems a more probable explanation of the preferential vulnerability of larger trees to climate change-induced drought. Other implications of selection favouring constant per-leaf area sapwood construction and maintenance costs are departure from the da Vinci rule expectation of similar sapwood areas across branching orders, and that extensive conduit furcation in the stem seems unlikely.

Conclusions

Because all these considerations impact the likelihood of vulnerability to hydraulic failure versus carbon starvation, both implicated as key suspects in forest mortality, we suggest that these predictions represent essential priorities for empirical testing.
Breast Implant Illness as a Clinical Entity: A Systematic Review of the Literature
Authors: Kabir Raeesa , Stanton Eloise , Sorenson Thomas J , Hemal Kshipra , Boyd Carter J , Karp Nolan S , Choi Mihye
Published: April 2024

Background

Breast implant illness (BII) has become a contentious subject in recent years. Although some studies have reported associations between breast implants and autoimmune diseases, others have failed to establish a definitive link.

Objectives

The objective of this study was to provide a comprehensive, up-to-date evaluation of the literature surrounding BII, with an emphasis on identifying patient-related factors that may be associated with BII.

Methods

A systematic review was performed following PRISMA guidelines by searching the PubMed (MEDLINE), Embase, and Cochrane databases for relevant studies published in the last 20 years.

Results

Thirty-one studies were included, which covered 39,505 implant patients with a mean [standard deviation] age of 44.2 [9.30] years. Fifteen studies reported implant explantation status, with 72.4% patients choosing to remove their implants. Among these, 9 studies reported symptom improvement in 83.5% patients. Fifty-three percent of patients undergoing explantation had total capsulectomy. Twenty-eight studies documented total numbers of patients experiencing symptoms related to BII, with 31.3% patients reporting such symptoms. Among these, 16 studies of 4109 BII patients distinguished whether the reason for implantation was cosmetic augmentation or reconstruction. When specified, more patients experiencing BII-related symptoms received implants for “cosmetic” vs “reconstructive” reasons (cosmetic, 3864/4109 [94.0%] vs reconstruction, 245/4109 [5.96%]; P < .001).

Conclusions

This review provides an overview of the current state of knowledge regarding BII. The study highlights a potential relationship between BII and indication for implants (cosmetic vs reconstructive) among other variables, offering valuable insight on factors associated with BII and directions for future research.

Level of Evidence: 3
TMBstable: a variant caller controls performance variation across heterogeneous sequencing samples
Authors: Wang Shenjie , Zhu Xiaoyan , Wang Xuwen , Liu Yuqian , Zhao Minchao , Chang Zhili , Wang Xiaonan , Shao Yang , Wang Jiayin
Published: April 2024

In cancer genomics, variant calling has advanced, but traditional mean accuracy evaluations are inadequate for biomarkers like tumor mutation burden, which vary significantly across samples, affecting immunotherapy patient selection and threshold settings. In this study, we introduce TMBstable, an innovative method that dynamically selects optimal variant calling strategies for specific genomic regions using a meta-learning framework, distinguishing it from traditional callers with uniform sample-wide strategies. The process begins with segmenting the sample into windows and extracting meta-features for clustering, followed by using a pre-trained meta-model to select suitable algorithms for each cluster, thereby addressing strategy-sample mismatches, reducing performance fluctuations and ensuring consistent performance across various samples. We evaluated TMBstable using both simulated and real non-small cell lung cancer and nasopharyngeal carcinoma samples, comparing it with advanced callers. The assessment, focusing on stability measures, such as the variance and coefficient of variation in false positive rate, false negative rate, precision and recall, involved 300 simulated and 106 real tumor samples. Benchmark results showed TMBstable’s superior stability with the lowest variance and coefficient of variation across performance metrics, highlighting its effectiveness in analyzing the counting-based biomarker. The TMBstable algorithm can be accessed at https://github.com/hello-json/TMBstable for academic usage only.
The effects of cholecalciferol and afamelanotide on vitamin D levels in erythropoietic protoporphyria: a multicentre cohort study
Authors: Kluijver Louisa G , Nekouei Shahraki Mitra , Wagenmakers Margreet A E M , Hanssen Bettina E , Kuerten Viola , Schelonke Kathrin , Homey Bernhard , Langendonk Janneke G
Published: April 2024

Background

Patients with erythropoietic protoporphyria experience lifelong painful photosensitivity resulting in a lack of sunlight exposure. Previous studies have shown that 47–63% of patients with EPP suffer from vitamin D deficiency and a high prevalence of osteoporosis. An effective treatment for EPP has been available since 2016: the α-melanocyte stimulating hormone analogue afamelanotide. So far, studies on vitamin D levels in EPP have only investigated patients who have not been treated with afamelanotide.

Objectives

To investigate the effects of afamelanotide treatment on vitamin D levels in EPP.

Methods

A multicentre observational cohort study in adults with EPP from the Erasmus Medical Centre, the Netherlands, and the University Hospital Düsseldorf, Germany, was carried out. Routinely collected vitamin D levels between 2005 and 2021 were used for analysis. Patient exposure to cholecalciferol or afamelanotide was categorized into four treatment groups: untreated, cholecalciferol, afamelanotide and combined treatment. A linear mixed model for longitudinal data was applied to measure the effect of the treatment groups compared with the untreated groups on vitamin D levels.

Results

A total of 230 patients and 1774 vitamin D measurements were included. The prevalence of vitamin D deficiency and severe deficiency remained high despite afamelanotide treatment (< 50 nmol L–1 in 71.8% of patients and < 30 nmol L–1 in 48.1%, respectively). Afamelanotide treatment alone did not lead to a significant average increase in vitamin D levels [β = 0.5, 95% confidence interval (CI) –3.2 to 4.2]. In contrast, cholecalciferol and combined therapy with afamelanotide led to a significant increase in vitamin D levels [β = 11.6 (95% CI 7.2–15.9) and β = 15.2 (95% CI 12.3–18.1), respectively].

Conclusions

Cholecalciferol remains essential for the treatment of vitamin D deficiency in EPP, irrespective of new treatment options like afamelanotide. Afamelanotide treatment did not affect vitamin D levels. We suggest that future guidelines include continuous monitoring of vitamin D and a prescription for cholecalciferol in all patients with EPP, including those treated with afamelanotide.
A novel variant in PTPN11, c.1277A>G p.(His426Arg), in a patient with Noonan syndrome with multiple lentigines
Authors: Kuo Olivia , Molloy Kevin , Sabir Ataf , Fleming Andrew , Edwards Matthew , Morris-Rosendahl Deborah , Fassihi Hiva , Preston Philip
Published: April 2024

Noonan syndrome with multiple lentigines (NSML) is a rare autosomal dominant condition arising from gene variants involved in the RAS-MAPK pathway. The presence of multiple skin cancers is not widely reported in NSML. We report on a novel missense variant causing NSML in a patient with an unusual distribution of lentigines and multiple skin cancers. An increased awareness of the potential for malignant change of lentigines in NSML may encourage regular skin surveillance as a mainstay of multidisciplinary management, enabling early diagnosis and management of skin cancers in this group of patients.
New insight into air pollution-related cardiovascular disease: an adverse outcome pathway framework of PM2.5-associated vascular calcification
Authors: Ding Ruiyang , Huang Linyuan , Yan Kanglin , Sun Zhiwei , Duan Junchao
Published: April 2024

Despite the air quality has been generally improved in recent years, ambient fine particulate matter (PM2.5), a major contributor to air pollution, remains one of the major threats to public health. Vascular calcification is a systematic pathology associated with an increased risk of cardiovascular disease. Although the epidemiological evidence has uncovered the association between PM2.5 exposure and vascular calcification, little is known about the underlying mechanisms. The adverse outcome pathway (AOP) concept offers a comprehensive interpretation of all of the findings obtained by toxicological and epidemiological studies. In this review, reactive oxygen species generation was identified as the molecular initiating event (MIE), which targeted subsequent key events (KEs) such as oxidative stress, inflammation, endoplasmic reticulum stress, and autophagy, from the cellular to the tissue/organ level. These KEs eventually led to the adverse outcome, namely increased incidence of vascular calcification and atherosclerosis morbidity. To the best of our knowledge, this is the first AOP framework devoted to PM2.5-associated vascular calcification, which benefits future investigations by identifying current limitations and latent biomarkers.
Continental-scale migration patterns and origin of Helicoverpa zea (Lepidoptera: Noctuidae) based on a biogeochemical marker
Authors: Paula-Moraes Silvana V , Calixto Eduardo S , Santos Abraão A , Reay-Jones Francis P F , Reisig Dominic D , Farhan Yasmine , Smith Jocelyn L , Hutchison William D
Published: April 2024

Insect migrations have ecological and economic impacts, particularly in agriculture. However, there is limited knowledge about the migratory movements of pests at the continental scale, which is an important factor influencing the spread of resistance genes. Understanding the migratory patterns of economic pests, like Helicoverpa zea (Boddie), is essential for improving Integrated Pest Management (IPM) and Insect Resistance Management (IRM) strategies. In this study, we used stable hydrogen isotopic ratios in wing tissue as a biogeochemical marker to examine migratory patterns and estimate the native origins of H. zea individuals collected across a wide latitudinal gradient in North America. Samples collected at higher latitudes (Ontario, Canada and Minnesota, USA) exhibited a greater proportion (60%–96%) of nonlocal individuals, with an increased probability of origin from the southeastern United States. Populations from mid-latitudes (Florida, North Carolina, and South Carolina) showed a blend of local and nonlocal (40%–60%) individuals. Finally, 15% of the southernmost population individuals (Puerto Rico) were classified as migratory, with some having a probability of origin at higher latitudes (>30°). Overall, our results provide evidence of a northward spring/summer migration of H. zea in North America and underscore the significance of the southeastern United States as a hub for genetic flow. In addition, based on stable hydrogen isotopic ratios, there is strong evidence of reverse (southward) migration of H. zea from the continental United States to Puerto Rico. Our study highlights the implications for IPM and IRM programs and the need for management strategies that account for both northward and southward migration patterns.
Reaching out to socially distant trainees: experimental evidence from variations on the standard farmer trainer system
Authors: Bertelli Olivia , Fall Fatou
Published: April 2024

The farmer trainer (FT) model has gained momentum as a cost-effective alternative to traditional agricultural extension systems. However, there may be friction in the transmission of information, whereby farmers closer to the FT may benefit more than socially distant farmers. This study explores whether variations on the standard FT model facilitate the diffusion of information outside the FT’s pre-existing social network. On top of a standard FT training, a sub-sample of voluntary FTs in rural Uganda was randomly assigned to receive (i) vouchers for accessing professional extension agents, (ii) a signpost advertising the trainer services or (iii) further training aimed at tailoring the training to the specific needs of the trainees. The results show that the FTs assigned these treatment variations trained more farmers, a larger proportion of whom belonged to the FT’s own close circle. The FTs who received vouchers were the only ones to reach out to more socially distant farmers and were also those who organized the most training sessions. We show that these effects are independent of any FT prominence in the village. Nevertheless, further evidence suggests exercising caution regarding the presence of friction in the transmission of knowledge, since knowledge and technology adoption appear to increase only among farmers closely connected to the FT.
Alkynyl-, vinyl-, and arylsilanes
Authors: Thomas Susan E.
Published: April 2024

This chapter studies the conversion of a terminal alkyne to its alkynylsilane. It displays how terminal alkynes are converted into alkynylsilanes by metallation and the addition of chlorosilane. The chapter also looks at the regioselective electrophilic attack on alkynylsilanes. It assesses how electrophiles react with alkynylsilanes at the silicon-bearing end of the alkyne. The chapter then moves to explore hydrosilylation and its application to the synthesis of vinylsilanes. It argues that the reaction is catalyssed by many transition-metal complexes — showing the mechanism for the hydrosilylation of an alkene under transition-metal catalysis. Finally, the chapter pays attention to how arylsilanes are prepared. It outlines the steps of the reaction, then shows how arylsilanes undergo a reaction with electrophiles known as ipso-desilylation.
Reactions of organoboranes
Authors: Thomas Susan E.
Published: April 2024

This chapter discusses the tetrahedral species known as an organoborate. It examines how the attacks by nucleophiles and subsequent 1,2-migration reactions dominate much of the reactivity of organoboranes. Organoboranes are normally handled under a nitrogen atmosphere as they are generally sensitive to oxidation processes. The chapter looks at how this is carried out using alkaline hydrogen peroxide when oxidation is required. It also reviews the oxidation of alklyboranes by using the alkaline hydrogen peroxide. Lastly, the chapter explores how aqueous chromic acid has been used to oxidize alklyboranes. It further discusses the concept of protonolysis, the hydroboration/protolytic cleavage of alkynes, and halogenolysis, the cleavage of the boron-carbon bonds by halogens.
Properties of organosilicon compounds
Authors: Thomas Susan E.
Published: April 2024

This chapter describes the properties of bonds to silicon. It exhibits the relative strengths of bonds that silicon and carbon form with some other elements, noting that silicon forms stronger bonds than carbon to oxygen and the halogens, and weaker bonds to carbon and hydrogen. The chapter points out that much of organosilicon chemistry is driven by the formation of strong silicon-oxygen or silicon-fluorine bonds at the expense of other weaker bonds. The chapter then moves to demonstrate the relative increases in bond lengths between selected atoms attached to silicon and the corresponding bond to carbon. It then introduces the concept of bond polarization and investigates why silicon is more electropositive than carbon. Next, the chapter elaborates on the nucleophilic substitution at a silicon centre, and the stabilization of beta-carbocations and alpha-carbon-metal bonds.
Protection of hydroxy groups as silyl ethers
Authors: Thomas Susan E.
Published: April 2024

This chapter illustrates the formation of silyl ethers. It gives attention to the trimethylsilyl group which has been used extensively for the protection of alcohols. One of the many methods which have been used for protecting a hydroxy group as its trimethylsilyl ether involves adding trimethylsilyl chloride (trimethylchlorosilane, TMCS) to the alcohol in the presence of a weak base. The chapter then argues that silyl ethers are cleaved to their parent alcohols by nucleophiles (often alcohols) under a range of acidic or basic conditions. Finally, the chapter shows some examples of protection of hydroxy groups as silyl ethers  emphasizing the synthesis of (R)-isoproterenol and the synthesis of gephyrotoxin.
Allylsilanes and acylsilanes
Authors: Thomas Susan E.
Published: April 2024

This chapter reviews some methods available for making allylsilanes. It focuses on the silylation of a metal-allyl species as the most direct method available for making them as well as the use of the Wittig reaction. Allylsilanes react with electrophiles at their γ carbon atom as attack at this position generates a carbocation β to silicon. Displacement of the silyl group subsequently produces a new alkene. The chapter then shifts to detail the method of synthesizing acylsilanes which involves deprotonation and silylation of the 1,3-derivative of an aldehyde. It considers how acylsilanes have been synthesized by several other approaches: a reverse Brook rearrangement (silyl-Wittig rearrangement) of allyltrimethylsilyl ether followed by oxidation and reductive cleavage of carbon-sulphur bonds in the silylenol ethers derived from thiol esters.
Exploring the Predictive Value of Gut Microbiome Signatures for Therapy Intensification in Patients With Inflammatory Bowel Disease: A 10-Year Follow-up Study
Authors: Al Radi Zainab M A , Prins Femke M , Collij Valerie , Vich Vila Arnau , Festen Eleonora A M , Dijkstra Gerard , Weersma Rinse K , Klaassen Marjolein A Y , Gacesa Ranko
Published: April 2024

Background

Inflammatory bowel diseases (IBDs) pose a significant challenge due to their diverse, often debilitating, and unpredictable clinical manifestations. The absence of prognostic tools to anticipate the future complications that require therapy intensification presents a substantial burden to patient private life and health. We aimed to explore whether the gut microbiome is a potential biomarker for future therapy intensification in a cohort of 90 IBD patients.

Methods

We conducted whole-genome metagenomics sequencing on fecal samples from these patients, allowing us to profile the taxonomic and functional composition of their gut microbiomes. Additionally, we conducted a retrospective analysis of patients’ electronic records over a period of 10 years following the sample collection and classified patients into (1) those requiring and (2) not requiring therapy intensification. Therapy intensification included medication escalation, intestinal resections, or a loss of response to a biological treatment. We applied gut microbiome diversity analysis, dissimilarity assessment, differential abundance analysis, and random forest modeling to establish associations between baseline microbiome profiles and future therapy intensification.

Results

We identified 12 microbial species (eg, Roseburia hominis and Dialister invisus) and 16 functional pathways (eg, biosynthesis of L-citrulline and L-threonine) with significant correlations to future therapy intensifications. Random forest models using microbial species and pathways achieved areas under the curve of 0.75 and 0.72 for predicting therapy intensification.

Conclusions

The gut microbiome is a potential biomarker for therapy intensification in IBD patients and personalized management strategies. Further research should validate our findings in other cohorts to enhance the generalizability of these results.
Genomic and Epigenomic Influences on Resilience across Scales: Lessons from the Responses of Fish to Environmental Stressors
Authors: Metzger David C H , Earhart Madison L , Schulte Patricia M
Published: April 2024

Synopsis

Understanding the factors that influence the resilience of biological systems to environmental change is a pressing concern in the face of increasing human impacts on ecosystems and the organisms that inhabit them. However, most considerations of biological resilience have focused at the community and ecosystem levels, whereas here we discuss how including consideration of processes occurring at lower levels of biological organization may provide insights into factors that influence resilience at higher levels. Specifically, we explore how processes at the genomic and epigenomic levels may cascade up to influence resilience at higher levels. We ask how the concepts of “resistance,” or the capacity of a system to minimize change in response to a disturbance, and “recovery,” or the ability of a system to return to its original state following a disturbance and avoid tipping points and resulting regime shifts, map to these lower levels of biological organization. Overall, we suggest that substantial changes at these lower levels may be required to support resilience at higher levels, using selected examples of genomic and epigenomic responses of fish to climate-change-related stressors such as high temperature and hypoxia at the levels of the genome, epigenome, and organism.
Density-dependent habitat selection and warming determine the spatial distribution of haddock (Melanogrammus aeglefinus) on Georges Bank
Authors: Wang Yanjun , Gao Jin , McCurdy Quinn
Published: April 2024

In an ever-changing environment, detecting shifts in the spatial distribution of marine fish and understanding the relative importance of climate change and biotic factors impacting fish distributions can improve fisheries management. Coincident with the significant increase in Haddock (Melanogrammus aeglefinus) abundance to a historically high levels on Georges Bank (GB) in the last decade, extreme ocean temperature increase was also observed in this region. In this study, the possible seasonal and inter-annual spatial distribution changes of haddock were investigated with >50 years of bottom trawl survey data collected in spring and fall on GB. These data were analyzed using models with spatial, different temporal, and spatio-temporal autocorrelation structures. To characterize the directional changes in haddock spatial distribution, the Center of Gravity (CG) and Area of Occupancy (AO) in each season were estimated from the best model selected by Akaike Information Criteria (AIC). The results showed substantial range expansion/contraction and distribution changes in both spring and fall over time. The relative role of density dependence, age structure, and climate change in affecting haddock distribution was evaluated using a generalized additive model (GAM). It was found that density-dependent habitat selection made the greatest contribution to the variations of AO in both seasons, which is consistent with the MacCall’s Basin model theory. Rising ocean temperatures played a major role in shaping a northward distribution shift in fall. GB is the southern edge of haddock distribution in the Northwest Atlantic, continued warming from climate model projections in the next 50 years in this region could make it difficult to define stock boundaries between GB and adjacent Canadian and US domestic management areas. This would subsequently impact fishery management of haddock.
Transitive Centralizer and Fibered Partially Hyperbolic Systems
Authors: Damjanović Danijela , Wilkinson Amie , Xu Disheng
Published: April 2024

We prove several rigidity results about the centralizer of a smooth diffeomorphism, concentrating on two families of examples: diffeomorphisms with transitive centralizer, and perturbations of isometric extensions of Anosov diffeomorphisms of nilmanifolds. We classify all smooth diffeomorphisms with transitive centralizer: they are exactly the maps that preserve a principal fiber bundle structure, acting minimally on the fibers and trivially on the base. We also show that for any smooth, accessible isometric extension $f_{0}\colon M\to M$ of an Anosov diffeomorphism of a nilmanifold, subject to a spectral bunching condition, any $f\in \textrm{Diff}^{\infty }(M)$ sufficiently $C^{1}$-close to $f_{0}$ has centralizer a Lie group. If the dimension of this Lie group equals the dimension of the fiber, then $f$ is a principal fiber bundle morphism covering an Anosov diffeomorphism. Using the results of this paper, we classify the centralizer of any partially hyperbolic diffeomorphism of a $3$-dimensional, nontoral nilmanifold: either the centralizer is virtually trivial, or the diffeomorphism is an isometric extension of an Anosov diffeomorphism, and the centralizer is virtually ${{\mathbb{Z}}}\times{{\mathbb{T}}}$.