bluuebunny/crossref_metadata_2025_split huggingface dataset:
Asymptotic behavior of the first Dirichlet eigenvalue of AHE manifolds
Authors: Jin Xiaoshang 
Published: April 2024

AbstractIn this article, we investigate the rate at which the first Dirichlet eigenvalue of geodesic balls decreases as the radius approaches infinity. We prove that if the conformal infinity of an asymptotically hyperbolic Einstein manifold is of nonnegative Yamabe type, then the two‐term asymptotic of the eigenvalues is the same as that in hyperbolic space.
The addition of blood flow restriction during resistance exercise does not increase prolonged low‐frequency force depression
Authors: Pignanelli Christopher , Robertson Alexa A. , Hirsch Steven M. , Power Geoffrey A. , Burr Jamie F. 
Published: April 2024

AbstractAt a given exercise intensity, blood flow restriction (BFR) reduces the volume of exercise required to impair post‐exercise neuromuscular function. Compared to traditional exercise, the time course of recovery is less clear. After strenuous exercise, force output assessed with electrical muscle stimulation is impaired to a greater extent at low versus high stimulation frequencies, a condition known as prolonged low‐frequency force depression (PLFFD). It is unclear if BFR increases PLFFD after exercise. This study tested if BFR during exercise increases PLFFD and slows recovery of neuromuscular function compared to regular exercise. Fifteen physically active participants performed six low‐load sets of knee‐extensions across four conditions: resistance exercise to task failure (RETF), resistance exercise to task failure with BFR applied continuously (BFRCONT) or intermittently (BFRINT), and resistance exercise matched to the lowest exercise volume condition (REVM). Maximal voluntary contraction (MVC) force output, voluntary activation and a force–frequency (1–100 Hz) curve were measured before and 0, 1, 2, 3, 4 and 24 h after exercise. Exercise to task failure caused similar reductions at 0 h for voluntary activation (RETF = 81.0 ± 14.2%, BFRINT = 80.9 ± 12.4% and BFRCONT = 78.6 ± 10.7%) and MVC force output (RETF = 482 ± 168 N, BFRINT = 432 ± 174 N, and BFRCONT = 443 ± 196 N), which recovered to baseline values between 4 and 24 h. PLFFD occurred only after RETF at 1 h supported by a higher frequency to evoke 50% of the force production at 100 Hz (1 h: 17.5 ± 4.4 vs. baseline: 15 ± 4.1 Hz, P = 0.0023), BFRINT (15.5 ± 4.0 Hz; P = 0.03), and REVM (14.9 ± 3.1 Hz; P = 0.002), with a trend versus BFRCONT (15.7 ± 3.5 Hz; P = 0.063). These findings indicate that, in physically active individuals, using BFR during exercise does not impair the recovery of neuromuscular function by 24 h post‐exercise.
Conceptual Configuration Analysis of Tetrahedral-Octahedral Heterogeneous Unit and Topological Design of Shape Morphing Mechanism
Authors: Guo Weiming , Xiao Hong , Guo Hongwei , Tao Jianguo , Deng Zongquan , Li Chuanyang 
Published: April 2024

Abstract
The truss static structure system has excellent large load and lightweight characteristics. It is easy to embed actuators by substituting specific members in the structure and has the potential for multidimensional space deformation. Inspired by uniform tessellation structures, this article proposes a novel shape morphing mechanism (SMM) based on the combined design of tetrahedral-octahedral heterogeneous units (TOHUs). The relationship between the motion properties and driving configuration of the tetrahedral-octahedral units is analyzed to determine their conceptual configuration based on graph theory. Then, the weighted graph, adjacency matrix, and connection rules are evaluated to synthesize the conceptual structure for the truss mechanism. The results show that this configuration can allow multidimensional continuous deformations, including span, bend, sweep, and twist. A prototype is built to verify its deformability. Finally, the stiffness performance is analyzed based on the matrix displacement method. This research provides a comprehensive design method for constructing SMM, expands the range of combinable units and connection methods, and offers theoretical guidance for the innovative design of multidimensional deformation SMM in aerospace.
An Improved Body Force Model to Simulate Blade Loading Variation Under Various Operating Conditions in Transonic Axial Flow Compressor
Authors: Liu Shijie , Pan Tianyu , Li Qiushi 
Published: April 2024

Abstract
In order to analyze the unsteady aerodynamic response of compressors with limited computational resources, the development of the body force (BF) model has been pursued for decades. This model can simulate the effects of the compressor blade on the flow by applying a three-dimensional (3D) force field. Indeed, the accuracy of the BF model simulation highly depends on the construction strategy of BF field. However, for a transonic compressor, the influence of shock waves on the spatial distribution of blade loading is significant, which makes the construction of an appropriate BF field challenging. To solve this issue, an accurate BF model is proposed to describe the effects of the blade on the flow with high spatial fidelity in transonic compressors. For verification, a typical transonic fan rotor, NASA-Rotor 67, is selected. The numerical results calculated by the new BF model are compared with those obtained by the Reynolds-averaged Navier–Stokes (RANS) solver. According to the results, the new model can accurately capture the distribution of blade loading in the transonic blade channel at various operating conditions, eventually leading to a good prediction of compressor performance and the radial distribution of flow parameters downstream of the rotor. Moreover, this study discusses the causes of modeling errors and presents the application of the model in inlet distortion simulation at the end.
Investigating the Wear Mechanism of TiAlN/TiN PVD-Coated WC Inserts in End Milling of Incoloy 925 Under Synergy of Bio-Degradable Fatty Acids and Nano-Metallic Solid Lubricant
Authors: Yadav Shravan Kumar , Ghosh Sudarsan , Sivanandam Aravindan 
Published: April 2024

Abstract
Rapid tool wear in machining difficult-to-cut material is a significant challenge since it is related to tool cost, surface integrity of machined components, and power consumption. The reduction in tool wear may be accomplished by cutting fluids, especially in modern biodegradable fatty acids. Because of its high lubricity, coconut oil is the best choice for lubricating fatty acids. However, this oil has poor heat transfer properties. Hence, to further improve its properties, copper (Cu) nanoparticles (NPs), which have a high thermal conductivity to cost ratio compared to other nanoparticles in addition to anti-frictional and anti-wear properties (due to self-repairing properties caused by their low shear strength and easy deposition on contacting surfaces), have been dispersed in coconut oil, thus creating a nano-lubricant (nanofluid). It is found that synthesized nano-lubricants perform better in thermo-physics and tribology than pure coconut oil. Further, research has been carried out on the combined effects of coconut oil and 0.3 vol% Cu-NPs on Incoloy 925's end milling performance and tool wear mechanism (viz., coating delamination, adhesion, abrasion, and oxidation). It is found that tool wear-rate is reduced, which in turn increases tool life, due to effective cooling and lubrication when nanofluid-based minimum quantity lubrication (NMQL)-assisted machining is performed rather than dry and pure oil-based minimum quantity lubrication (MQL) conditions. Consequently, energy consumption in machining and surface quality of machined components are improved.
Zr0.1Fe0.9V1.1Mo0.9O7 as Cathode for Lithium-Ion Battery
Authors: Yuan Baohe , An Zheng , Qi Heng , Chen Jianming , Xu Qi 
Published: April 2024

Abstract
With the development of lithium-ion batteries, high capacity and high cycle stability have been the two main goals being pursued. Recent studies have shown that ZrV2O7 does not perform well in energy storage due to its low electrical conductivity and poor cycling stability. Elemental doping has proven to be an effective strategy for improving electrochemical performance. In this paper, we prepared Zr0.1Fe0.9V1.1Mo0.9O7(ZFVMO) and Zr0.1Fe0.9V1.1Mo0.9O7@c (ZFVMO@c) materials using a simple solid-phase sintering method and a fast microwave sintering method. Double ionic heterovalent substitution of Zr4+/V5+ in ZrV2O7 using Fe3+/Mo6+, Fe3+/Mo6+ gives it near-zero thermal expansion characteristics and excellent conductive properties. In electrochemical tests, the first discharge capacities of ZFVMO and ZFVMO@C are 2261 mA h g−1 and 727 mA h g−1, respectively, and the batteries were finally stabilized for 475 and 500 cycles. Compared to ZrV2O7, the electrochemical properties of ZFVMO are greatly improved.
Nationwide genome surveillance of carbapenem-resistant
Pseudomonas aeruginosa
in Japan
Authors: Yano Hirokazu , Hayashi Wataru , Kawakami Sayoko , Aoki Sadao , Anzai Eiko , Zuo Hui , Kitamura Norikazu , Hirabayashi Aki , Kajihara Toshiki , Kayama Shizuo , Sugawara Yo , Yahara Koji , Sugai Motoyuki 
Published: April 2024

ABSTRACT

Japan is a country with an approximate 10% prevalence rate of carbapenem-resistant
Pseudomonas aeruginosa
(CRPA). Currently, a comprehensive overview of the genotype and phenotype patterns of CRPA in Japan is lacking. Herein, we conducted genome sequencing and quantitative antimicrobial susceptibility testing for 382 meropenem-resistant CRPA isolates that were collected from 78 hospitals across Japan from 2019 to 2020. CRPA exhibited susceptibility rates of 52.9%, 26.4%, and 88.0% against piperacillin–tazobactam, ciprofloxacin, and amikacin, respectively, whereas 27.7% of CRPA isolates was classified as difficult-to-treat resistance
P. aeruginosa
. Of the 148 sequence types detected, ST274 (9.7%) was predominant, followed by ST235 (7.6%). The proportion of urine isolates in ST235 was higher than that in other STs (
P
= 0.0056, χ
2
test). Only 4.1% of CRPA isolates carried the carbapenemase genes:
bla
GES
(2) and
bla
IMP
(13). One ST235 isolate carried the novel
bla
IMP
variant
bla
IMP-98
in the chromosome. Regarding chromosomal mutations, 87.1% of CRPA isolates possessed inactivating or other resistance mutations in
oprD
, and 28.8% showed mutations in the regulatory genes (
mexR
,
nalC
, and
nalD
) for the MexAB-OprM efflux pump. Additionally, 4.7% of CRPA isolates carried a resistance mutation in the PBP3-encoding gene
ftsI
. The findings from this study and other surveillance studies collectively demonstrate that CRPA exhibits marked genetic diversity and that its multidrug resistance in Japan is less prevailed than in other regions. This study contributes a valuable data set that addresses a gap in genotype/phenotype information regarding CRPA in the Asia–Pacific region, where the epidemiological background markedly differs between regions.
Genomic context as well as sequence of both
psr
and penicillin-binding protein 5 contributes to β-lactam resistance in
Enterococcus faecium
Authors: Singh Kavindra V. , Galloway-Peña Jessica , Montealegre Maria Camila , Dong Xingxing , Murray Barbara E. 
Published: April 2024

ABSTRACT

Penicillin-binding protein 5 (PBP5) of
Enterococcus faecium
(
Efm
) is vital for ampicillin resistance (AMP-R). We previously designated three forms of PBP5, namely, PBP5-S in
Efm
clade B strains [ampicillin susceptible (AMP-S)], PBP5-S/R (AMP-S or R), and PBP5-R (AMP-R) in clade A strains. Here,
pbp5
deletion resulted in a marked reduction in AMP minimum inhibitory concentrations (MICs) to 0.01–0.09 µg/mL for clade B and 0.12–0.19 µg/mL for clade A strains;
in situ
complementation restored parental AMP MICs. Using D344SRF (lacking
ftsW/psr/pbp5
), constructs with
ftsW
A
/psr
A
(from a clade A1 strain) cloned upstream of
pbp5-S
and
pbp5-S/R
alleles resulted in modest increases in MICs to 3–8 µg/mL, while high MICs (
>
64 µg/mL) were seen using
pbp5
from A1 strains. Next, using
ftsW ± psr
from clade B and clade A/B and B/A hybrid constructs, the presence of
psr
B
, even alone or in
trans
, resulted in much lower AMP MICs (3–8 µg/mL) than when
psr
A
was present (MICs
>
64 µg/mL). qRT PCR showed relatively greater
pbp5
expression (
P
= 0.007) with
pbp5
cloned downstream of clade A1
ftsW/psr
(MIC
>
128 µg/mL) vs when cloned downstream of clade B
ftsW/psr
(MIC 4–16 µg/mL), consistent with results in western blots. In conclusion, we report the effect of clade A vs B
psr
on AMP MICs as well as the impact of
pbp5
alleles from different clades. While previously, Psr was not thought to contribute to AMP MICs in
Efm,
our results showed that the presence of

psr
B

resulted in a major decrease in
Efm
AMP MICs.

IMPORTANCE

The findings of this study shed light on ampicillin resistance in
Enterococcus faecium
clade A strains. They underscore the significance of alterations in the amino acid sequence of penicillin-binding protein 5 (PBP5) and the pivotal role of the psr region in PBP5 expression and ampicillin resistance. Notably, the presence of a full-length psrB leads to reduced PBP5 expression and lower minimum inhibitory concentrations (MICs) of ampicillin compared to the presence of a shorter psrA, regardless of the pbp5 allele involved. Additionally, clade B
E. faecium
strains exhibit lower AMP MICs when both
psr
alleles from clades A and B are present, although it is important to consider other distinctions between clade A and B strains that may contribute to this effect. It is intriguing to note that the divergence between clade A and clade B
E. faecium
and the subsequent evolution of heightened AMP MICs in hospital-associated strains appear to coincide with changes in
Pbp5
and
psr
. These changes in
psr
may have resulted in an inactive Psr, facilitating increased PBP5 expression and greater ampicillin resistance. These results raise the possibility that a mimicker of PsrB, if one could be designed, might be able to lower MICs of ampicillin-resistant
E. faecium
, thus potentially resorting ampicillin to our therapeutic armamentarium for this species.
PfCAP-H is essential for assembly of condensin I complex and karyokinesis during asexual proliferation of
Plasmodium falciparum
Authors: Gurung Pratima , McGee James P. , Dvorin Jeffrey D. 
Published: April 2024

ABSTRACT

Condensin I is a pentameric complex that regulates the mitotic chromosome assembly in eukaryotes. The kleisin subunit CAP-H of the condensin I complex acts as a linchpin to maintain the structural integrity and loading of this complex on mitotic chromosomes. This complex is present in all eukaryotes and has recently been identified in
Plasmodium
spp. However, how this complex is assembled and whether the kleisin subunit is critical for this complex in these parasites are yet to be explored. To examine the role of PfCAP-H during cell division within erythrocytes, we generated an inducible PfCAP-H knockout parasite. We find that PfCAP-H is dynamically expressed during mitosis with the peak expression at the metaphase plate. PfCAP-H interacts with PfCAP-G and is a non-SMC member of the condensin I complex. Notably, the absence of PfCAP-H does not alter the expression of PfCAP-G but affects its localization at the mitotic chromosomes. While mitotic spindle assembly is intact in PfCAP-H-deficient parasites, duplicated centrosomes remain clustered over the mass of unsegmented nuclei with failed karyokinesis. This failure leads to the formation of an abnormal nuclear mass, while cytokinesis occurs normally. Altogether, our data suggest that PfCAP-H plays a crucial role in maintaining the structural integrity of the condensin I complex on the mitotic chromosomes and is essential for the asexual development of malarial parasites.

IMPORTANCE

Mitosis is a fundamental process for
Plasmodium
parasites, which plays a vital role in their survival within two distinct hosts—human and
Anopheles
mosquitoes. Despite its great significance, our comprehension of mitosis and its regulation remains limited. In eukaryotes, mitosis is regulated by one of the pivotal complexes known as condensin complexes. The condensin complexes are responsible for chromosome condensation, ensuring the faithful distribution of genetic material to daughter cells. While condensin complexes have recently been identified in
Plasmodium
spp., our understanding of how this complex is assembled and its precise functions during the blood stage development of
Plasmodium falciparum
remains largely unexplored. In this study, we investigate the role of a central protein, PfCAP-H, during the blood stage development of
P. falciparum
. Our findings reveal that PfCAP-H is essential and plays a pivotal role in upholding the structure of condensin I and facilitating karyokinesis.
Uncovering the roles of
Mycobacterium tuberculosis melH
in redox and bioenergetic homeostasis: implications for antitubercular therapy
Authors: Chen Yu-Ching , Yang Xinxin , Wang Nan , Sampson Nicole S. 
Published: April 2024

ABSTRACT

Mycobacterium tuberculosis
(
Mtb
), the pathogenic bacterium that causes tuberculosis, has evolved sophisticated defense mechanisms to counteract the cytotoxicity of reactive oxygen species (ROS) generated within host macrophages during infection. The
melH
gene in
Mtb
and
Mycobacterium marinum
(
Mm
) plays a crucial role in defense mechanisms against ROS generated during infection. We demonstrate that
melH
encodes an epoxide hydrolase and contributes to ROS detoxification. Deletion of
melH
in
Mm
resulted in a mutant with increased sensitivity to oxidative stress, increased accumulation of aldehyde species, and decreased production of mycothiol and ergothioneine. This heightened vulnerability is attributed to the increased expression of
whiB3
, a universal stress sensor. The absence of
melH
also resulted in reduced intracellular levels of NAD
+
, NADH, and ATP. Bacterial growth was impaired, even in the absence of external stressors, and the impairment was carbon source dependent. Initial MelH substrate specificity studies demonstrate a preference for epoxides with a single aromatic substituent. Taken together, these results highlight the role of
melH
in mycobacterial bioenergetic metabolism and provide new insights into the complex interplay between redox homeostasis and generation of reactive aldehyde species in mycobacteria.

IMPORTANCE

This study unveils the pivotal role played by the
melH
gene in
Mycobacterium tuberculosis
and in
Mycobacterium marinum
in combatting the detrimental impact of oxidative conditions during infection. This investigation revealed notable alterations in the level of cytokinin-associated aldehyde,
para
-hydroxybenzaldehyde, as well as the redox buffer ergothioneine, upon deletion of
melH
. Moreover, changes in crucial cofactors responsible for electron transfer highlighted
melH
’s crucial function in maintaining a delicate equilibrium of redox and bioenergetic processes. MelH prefers epoxide small substrates with a phenyl substituted substrate. These findings collectively emphasize the potential of
melH
as an attractive target for the development of novel antitubercular therapies that sensitize mycobacteria to host stress, offering new avenues for combating tuberculosis.
Lactobacillus rhamnosus
HN001 facilitates the efficacy of dual PI3K/mTOR inhibition prolonging cardiac transplant survival and enhancing antitumor effect
Authors: Miao Xiaolong , Jiang Peng , Zhang Xiaotong , Li Xinqiang , Wu Zelai , Jiang Yuancong , Liu Han , Xie Weixun , Li Xinwei , Shi Bingfeng , Cai Jinzhen , Gong Weihua 
Published: April 2024

ABSTRACT

Solid organ transplantation is a crucial treatment for patients who have reached the end stage of heart, lung, kidney, or liver failure. However, the likelihood of developing cancer post-transplantation increases. Additionally, primary malignant tumors remain a major obstacle to the long-term survival of transplanted organs. Therefore, it is essential to investigate effective therapies that can boost the immune system’s ability to combat cancer and prevent allograft rejection. We established a mouse orthotopic liver tumor model and conducted allogeneic heterotopic heart transplantation. Various treatments were administered, and survival curves were generated using the Kaplan–Meier method. We also collected graft samples and measured inflammatory cytokine levels in the serum using an inflammatory array. The specificity of the histochemical techniques was tested by staining sections. We administered a combination therapy of phosphoinositide 3-kinase/mammalian target of rapamycin (PI3K/mTOR) dual inhibitor BEZ235 and
Lactobacillus rhamnosus
HN001 to primary liver cancer model mice with cardiac allografts. Consistent with our prior findings,
L. rhamnosus
HN001 alleviated the intestinal flora imbalance caused by BEZ235. Our previous research confirmed that the combination of BEZ235 and
L. rhamnosus
HN001 significantly prolonged cardiac transplant survival.

IMPORTANCE

We observed that the combination of phosphoinositide 3-kinase/mammalian target of rapamycin (PI3K/mTOR) dual inhibitor BEZ235 and
Lactobacillus rhamnosus
HN001 notably prolonged cardiac transplant survival while also inhibiting the progression of primary liver cancer. The combination therapy was efficacious in treating antitumor immunity and allograft rejection, as demonstrated by the efficacy results. We also found that this phenomenon was accompanied by the regulation of inflammatory IL-6 expression. Our study presents a novel and effective therapeutic approach to address antitumor immunity and prevent allograft rejection.
Death rattle: palliative nursing practices Delphi study
Authors: Oda Sumika , Kawakami Aki , Ashida Kaoru , Tanaka Makoto 
Published: April 2024

ObjectivesInterventions for patients with death rattle remain under consideration, and their families strongly acknowledge the need for improved care. However, few reports exist concerning specific and comprehensive nursing practices for them. This study aimed to clarify nursing practices for patients with death rattle and their families in hospital wards and examine each practice’s importance.MethodsWe used a modified Delphi method with expert nurses with extensive experience in end-of-life care. Participants were recruited using convenience and snowball sampling. First, we developed a list of nursing practices through a literature review and individual interviews. Second, we conducted the Delphi survey. Two rounds of judging were performed. Items were rated on a 9-point Likert scale (1=not important at all to 9=very important). An item was considered ‘important’ if at least 80% of the participants rated it ≥7.ResultsThe list comprised 40 items across 8 domains: assessment of death rattle and the distress felt by the patients, oral care, repositioning, adjustment of parenteral hydration, suctioning, administration of alleviating medications, communication with and assessment of family members who witness death rattle, and nurse’s attitude towards death rattle and the relevant interventions. Of the 46 recruited experts, 42 participated in both rounds. Participants regarded 37 of the 40 items as important.ConclusionsThis study specifically and comprehensively identified nursing practices for patients with death rattle and their families using a modified Delphi method to support clinical nursing practice and improve the quality of care.