bluuebunny/crossref_metadata_2025 huggingface dataset:
Human disturbance is the major driver of vegetation changes in the Caatinga dry forest region
Authors: Araujo Helder F. P. , Canassa Nathália F. , Machado Célia C. C. , Tabarelli Marcelo
Published: October 2023

Drastic changes in vegetation structure caused by exceeding ecological thresholds have fueled the interest in tropical forest responses to climate and land-use changes. Here, we examine the potential successional trajectories experienced by the largest dry tropical forest region in South America, driven by climate conditions and human disturbance. We built potential distribution models for vertebrate taxa associated with forest or shrub habitats to estimate natural vegetation cover. Distribution patterns were compared to current vegetation across the entire region to identify distinct forest degradation levels. Our results indicate the region has climatic and soil conditions suitable for more forest cover than is currently found, even in some areas with limited precipitation. However, 11.04% of natural cover persists across such an immense region, with only 4.34% consisting of forest cover. Forest degradation is characterized by the dramatic expansion of shrubland (390%), farming, and non-vegetation cover due to changes in land-use, rather than climatic conditions. Although different climate conditions have been the principal drivers for natural forest distribution in the region, the forest seems unable to resist the consequences of land-use changes, particularly in lower precipitation areas. Therefore, land-use change has exceeded the ecological thresholds for the persistence of forests, while climate change may exacerbate vegetation-type transitions.
An in vitro model and the underlying pathways of sinonasal inverted papilloma development
Authors: Nukpook Thawaree , Kiyono Tohru , Ekalaksananan Tipaya , Kasemsiri Pornthep , Teeramatwanich Watchareporn , Vatanasapt Patravoot , Chaiwiriyakul Surachat , Nakahara Tomomi , Pientong Chamsai
Published: October 2023

Recently, the specific association between Sinonasal inverted papilloma (SIP) and EGFR exon 20 mutations has been reported. To investigate the link between specific EGFR mutations and SIP development, we established organotypic raft culture system using nasal polyp-derived immortalized NP2 (iNP2) cells expressing EGFR exon 20 mutants or an exon 19 mutant, and SIP-derived iIP4 cells harboring P772_H773insPYNP mutation. In the raft culture, iIP4 cells showed the inverted growth pattern characteristic to SIP. Interestingly, iNP2 cells expressing EGFR exon 20 duplication mutants, S768_D770dup and N771_H773dup, but not of EGFR exon 19 mutant, E746_A750del, showed the inverted growth pattern. Enhanced activation of the PI3K/AKT signaling pathway was observed in iNP2_S768_D770dup and iIP4 cells, while increased MAPK signaling was found in iNP2_N771_H773dup. Increased cell migration and invasion were found in all cells carrying EGFR mutations when compared to iNP2 cells, and this effect was inhibited by either PI3K or MEK inhibitor. Notably, iNP2 cells expressing the N771_H773dup mutant showed the highest migration and invasion abilities. These results suggest that specific mutations in EGFR exon 20 play a crucial role in SIP development, partially though hyper-activation of the PI3K/AKT and MAPK signaling pathways. This study presents the first in vitro model for SIP development, which could facilitate further investigations into SIP pathogenesis and preclinical studies for new therapeutic agents.
The release of inhibition model reproduces kinetics and plasticity of neurotransmitter release in central synapses
Authors: Norman Christopher A. , Krishnakumar Shyam S. , Timofeeva Yulia , Volynski Kirill E.
Published: October 2023

Calcium-evoked release of neurotransmitters from synaptic vesicles (SVs) is catalysed by SNARE proteins. The predominant view is that, at rest, complete assembly of SNARE complexes is inhibited (‘clamped’) by synaptotagmin and complexin molecules. Calcium binding by synaptotagmins releases this fusion clamp and triggers fast SV exocytosis. However, this model has not been quantitatively tested over physiological timescales. Here we describe an experimentally constrained computational modelling framework to quantitatively assess how the molecular architecture of the fusion clamp affects SV exocytosis. Our results argue that the ‘release-of-inhibition’ model can indeed account for fast calcium-activated SV fusion, and that dual binding of synaptotagmin-1 and synaptotagmin-7 to the same SNARE complex enables synergistic regulation of the kinetics and plasticity of neurotransmitter release. The developed framework provides a powerful and adaptable tool to link the molecular biochemistry of presynaptic proteins to physiological data and efficiently test the plausibility of calcium-activated neurotransmitter release models.
Hydrophobic gating in bundle-crossing ion channels: a case study of TRPV4
Authors: Huang Jian , Chen Jianhan
Published: October 2023

Transmembrane ion channels frequently regulate ion permeation by forming bundle crossing of the pore-lining helices when deactivated. The resulting physical constriction is believed to serve as the de facto gate that imposes the major free energy barrier to ion permeation. Intriguingly, many ion channels also contain highly hydrophobic inner pores enclosed by bundle crossing, which can undergo spontaneous dewetting and give rise to a “vapor barrier” to block ion flow even in the absence of physical constriction. Using atomistic simulations, we show that hydrophobic gating and bundle-crossing mechanisms co-exist and complement one and another in the human TRPV4 channel. In particular, a single hydrophilic mutation in the lower pore can increase pore hydration and reduce the ion permeation free energy barrier by about half without affecting the bundle crossing. We believe that hydrophobic gating may play a key role in other bundle-crossing ion channels with hydrophobic inner pores.
Wastewater-influenced estuaries are characterized by disproportionately high nitrous oxide emissions but overestimated IPCC emission factor
Authors: Dong Yue , Liu Jia , Cheng Xiang , Fan Fuqiang , Lin Wei , Zhou Chunyang , Wang Shengrui , Xiao Shangbin , Wang Chenghao , Li Yu , Li Changlin
Published: October 2023

Estuaries play an important role in the global nitrous oxide budget. However, considerable uncertainties exist in estimating their nitrous oxide emissions, largely due to anthropogenic impacts, particularly wastewater discharge. Here we investigate nitrous oxide emission dynamics in the Pearl River Estuary through advanced high-resolution, real-time measurements. Results suggest that Pearl River Estuary is a strong nitrous oxide emission source (1.05 Gg yr−1; range: 0.92–1.23 Gg yr−1) with pronounced spatial heterogeneity. Wastewater discharge substantially impacts emissions by introducing abundant nutrients, altering carbon-to-nitrogen stoichiometry, and stimulating biochemical processes. A meta-analysis further reveals the widespread enhancement of nitrous oxide emission induced by wastewater nitrogen input in global estuaries, with nitrous oxide emission factors considerably lower than that suggested by the IPCC owing to progressive biological saturation. Consequently, refining emission factor estimates through comprehensive bottom-up studies is imperative to improve the understanding of estuarine contributions to the global nitrous oxide budget.
2-Imidazolidone metal complexes: increased hydrogen bonds and fused ring ligand ratio to be insensitive
Authors: Kuang Baolong , Wang Tingwei , Zhang Chao , Zhang Han , Lu Zujia , Xie Zhiming , Xu Meiqi , Yi Zhenxin , Zhang Jianguo
Published: October 2023

The two ECPs were prepared using 2-imidazolidone as a ligand, and the structure–activity relationship was studied. ECCs-1 possesses a higher density, enhanced detonation performance, and mechanical insensitivity.
Heavy element incorporation in nitroimidazole radiosensitizers: molecular-level insights into fragmentation dynamics
Authors: Svensson Pamela H. W. , Schwob Lucas , Grånäs Oscar , Unger Isaak , Björneholm Olle , Timneanu Nicusor , Lindblad Rebecka , Vieli Anna-Lydia , Zamudio-Bayer Vicente , Timm Martin , Hirsch Konstantin , Caleman Carl , Berholts Marta
Published: October 2023

The present study investigates the photofragmentation behavior of iodine-enhanced nitroimidazole-based radiosensitizer model compounds in their protonated form using near-edge X-ray absorption mass spectrometry and quantum mechanical calculations.
Designing biodegradable alternatives to commodity polymers
Authors: Fiandra Emanuella F. , Shaw Lloyd , Starck Matthieu , McGurk Christopher J. , Mahon Clare S.
Published: October 2023

This tutorial review explores the concepts of sustainable design and biodegradability, as applied to the design of synthetic polymers intended for use at scale.
Highly transparent polyurethane thermosets with tunable properties and enzymatic degradability derived from polyols originating from hemicellulosic sugars
Authors: Kasmi Nejib , Chebbi Yosra , Lorenzetti Alessandra , Hakkarainen Minna
Published: October 2023

A novel portfolio of highly transparent aliphatic polyurethane thermosets synthesized under very mild conditions from 100% renewable branched polyesters exhibiting “on demand” tunable mechanical and thermal properties and enzymatic degradability.
Targeted photodynamic therapy for breast cancer: the potential of glyconanoparticles
Authors: Thomas-Moore Brydie A. , Dedola Simone , Russell David A. , Field Robert A. , Marín María J.
Published: October 2023

Glyconanoparticles selectively bind to cellular targetsviaglycan–lectin interactions and are excellent drug-delivery systems for targeted photodynamic therapy of cancer.
Investigating evidence in support of validity and reliability for data collected with the meaningful learning in the laboratory instrument (MLLI)
Authors: Vaughan Elizabeth B. , Montoya-Cowan A. , Barbera Jack
Published: October 2023

The Meaningful Learning in the Laboratory Instrument (MLLI) was designed to measure students’ expectations before and after their laboratory courses and experiences. Although the MLLI has been used in various studies and laboratory environments to investigate students’ cognitive and affective laboratory expectations, the authors of the instrument reported a discrepancy between the intended factor structure of the MLLI and the factor structure suggested by the data collected in preliminary studies. Therefore, the aim of this study was to investigate the validity and reliability evidence related to data collected with the MLLI, especially that related to structural validity. Evidence to support structural validity would provide greater meaning for the reporting and interpretation of MLLI scores. In this study, two possible a priori models for the factor structure of data collected from multiple institutions with the MLLI were investigated using confirmatory factory analysis (CFA). This initial investigation found poor data-model fit for each of the two tested models. Cognitive interviews and free response items were then used to inform modifications to the two a priori structures, and a third alternative structure, which included a negative method factor, was also investigated. Once a best fitting model was identified, further model revisions were informed by a combination of modification indices and qualitative data. Evidence of adequate-to-good data model fit was found for the final revised version of the MLLI, deemed the MLLIv2. Additionally, evidence of both internal structure validity and single administration reliability were found for each of the MLLIv2 factors. The structure of the data from these items leads to scale scores that likely represent student expectations that contribute to meaningful learning and student expectations that detract from meaningful learning. As the results of this study provide the first psychometrically supported scales for MLLI data, they have implications on the future reporting and analyses of MLLI scores.
Sex Differences in the Speech of Persons With and Without Parkinson's Disease
Authors: Houle Nichole , Feaster Taylor , Mira Amna , Meeks Kirsten , Stepp Cara E.
Published: October 2023

Background:

Sex differences are apparent in the prevalence and the clinical presentation of Parkinson's disease (PD), but their effects on speech have been less studied.

Method:

Speech acoustics of persons with (34 females and 34 males) and without (age- and sex-matched) PD were examined, assessing the effects of PD diagnosis and sex on ratings of dysarthria severity and acoustic measures of phonation (fundamental frequency standard deviation, smoothed cepstral peak prominence), speech rate (net syllables per second, percent pause ratio), and articulation (articulatory–acoustic vowel space, release burst precision).

Results:

Most measures were affected by PD (dysarthria severity, fundamental frequency standard deviation) and sex (smoothed cepstral peak prominence, net syllables per second, percent pause ratio, articulatory–acoustic vowel space), but without interactions between them. Release burst precision was differentially affected by sex in PD. Relative to those without PD, persons with PD produced fewer plosives with a single burst: females more frequently produced multiple bursts, whereas males more frequently produced no burst at all.

Conclusions:

Most metrics did not indicate that speech production is differentially affected by sex in PD. Sex was, however, associated with disparate effects on release burst precision in PD, which deserves further study.

Supplemental Material:

https://doi.org/10.23641/asha.24388666
Alterations and Preservations: Practices and Perspectives of Speech-Language Pathologists Regarding the Intervention of Thickened Liquids for Swallowing Problems
Authors: McCurtin Arlene , Byrne Hannah , Collins Lindsey , McInerney Michelle , Lazenby-Paterson Tracy , Leslie Paula , O'Keeffe Shaun , O'Toole Claire , Smith Alison
Published: October 2023

Purpose:

The intervention of thickened liquids (TL) is commonly used to reduce aspiration in people with dysphagia. Speech-language pathologists (SLPs) have traditionally believed it is an effective intervention. Recent articles highlight limited evidence, poor acceptance, and a variety of unintended consequences. This study explores if current debates have been reflected in SLP practices and perspectives.

Method:

An e-survey was developed. Participants were recruited via professional associations in Australia, New Zealand, Ireland, the United Kingdom, and the United States. Descriptive and inferential statistics were used to explore the data. Principal component analysis was used to summarize SLP practices and perspectives.

Results:

The 370 respondents represented mainly experienced, confident, hospital-based clinicians. While 20% of respondents frequently recommend TL, 61% believe it to be a burdensome treatment. “Best treatment” and “It works” beliefs continue to underpin decision making. Those who recommend TL most often are most influenced by penetration, coughing, and their own clinical experience. They are more likely to believe TL is evidence based and effective, reduces aspiration, and improves hydration. Person-centeredness is important among all respondents, although significant numbers would implement TL against patient wishes. Improvements in aspiration status and quality of life rank highly as reasons to discontinue TL.

Conclusions:

The results of this study suggest that fewer respondents are regularly using TL. Divergent groups are evident with those frequently employing and believing in the efficacy of TL and those who do not. While current debates are influencing practice, there clearly remains a significant number of SLPs continuing to recommend TL. This study's findings highlight both alterations and preservations in the discipline's approach to TL and calls for SLPs to reframe our thinking regarding this intervention as well as consider alternative options in this treatment space.

Supplemental Material:

https://doi.org/10.23641/asha.24317110
The Stability and Validity of Automated Indices of Vocal Development in Infants With Autistic and Non-Autistic Siblings
Authors: Markfeld Jennifer E. , Feldman Jacob I. , Daly Claire , Santapuram Pooja , Bowman Sarah M. , Dunham-Carr Kacie , Suzman Evan , Keçeli-Kaysılı Bahar , Woynaroski Tiffany G.
Published: October 2023

Purpose:

This study evaluates the extent to which automated indices of vocal development are stable and valid for predicting language in infants at increased familial likelihood for autism and/or language impairment and relatively lower likelihood infants.

Method:

A group of infants with autistic siblings (Sibs-autism; 20 infants) and a comparison group of infants with non-autistic siblings (Sibs-NA; 20 infants) wore Language ENvironment Analysis (LENA) recording devices for 16 hr on 2 days within a 1-week period. Extant software was used to derive several putative indices of vocal development from these recordings. Stability of these variables was examined across and within groups. Expressive and receptive language aggregates were calculated for each participant. Multiple regression analyses were used to (a) evaluate zero-order correlations for variables derived from LENA recordings with concurrent and future language and (b) test whether those associations were moderated by group status.

Results:

Both stability and validity differed by variable and group status. All variables reached acceptable stability in the Sibs-autism group within two to three observations, whereas stability of most variables was attenuated in the Sibs-NA group. No variables were associated with concurrent language in the theoretically motivated direction across groups, but two variables were strongly associated with concurrent expressive language in only the Sibs-NA group. Additionally, two variables were associated with later expressive language, though these correlations were again stronger in the Sibs-NA versus Sibs-autism group.

Conclusions:

Although selected automated indices of vocal development were stable in Sibs-autism and/or valid for predicting expressive language within Sibs-NA, no scores showed strong, theoretically motivated associations with language within the Sibs-autism group. Automated indices of vocal development may, thus, have limited validity or clinical utility for predicting language development in infants at elevated familial likelihood for autism.

Supplemental Material:

https://doi.org/10.23641/asha.24415735
The Effect of Language Dominance on Classic Semantic, Action, Emotional, and Phonemic Fluency in Unbalanced Bilinguals
Authors: Lam Boji P. W. , Yoon Jiyoung
Published: October 2023

Objective:

Verbal fluency evaluation in bilingual speakers should include dual-language assessment to obtain a comprehensive profile of word retrieval abilities. This study is the first to compare classic semantic, action, emotional, and phonemic fluency in terms of the magnitude of their performance gaps between the dominant and nondominant language in unbalanced bilingual speakers. We also examined the quantitative relationship between language dominance and verbal fluency performance.

Method:

Twenty-six bilingual adults completed a comprehensive set of classic semantic (“animals,” “vegetables”), action (“do”), emotional (“happy,” “sad,” “afraid”), and phonemic (“F,” “A,” “S”) fluency tasks in their dominant language (English) and nondominant language (Spanish) in two sessions on separate days. Participants also completed subjective and objective measures of language proficiency.

Results:

All tasks yielded fewer correct responses in the nondominant language. The between-languages performance gap was the largest for “animals” and the smallest for emotional fluency. “Happy” yielded the most balanced performance among all semantic tasks and a positivity bias that was unaffected by language dominance. Finally, language dominance scores computed by a newly developed formula indicated relationships between self-rated proficiency and fluency performance.

Conclusions:

This study provides preliminary, normative data of classic semantic, action, emotional, and phonemic fluency that could be used to gauge unbalanced bilingual speakers' performance. Significant impacts of language dominance on “animals” demand caution in using this widely used classic semantic category in evaluating bilingual speakers' performance. The data also underscore the robustness of positivity biases in emotional fluency and the validity of using subjective measures to supplement neuropsychological assessment of fluency performance.
Associations Between Physiological Correlates of Cochlear Synaptopathy and Tinnitus in a Veteran Population
Authors: Bramhall Naomi F. , Theodoroff Sarah M. , McMillan Garnett P. , Kampel Sean D. , Buran Brad N.
Published: October 2023

Purpose:

Animal models and human temporal bones indicate that noise exposure is a risk factor for cochlear synaptopathy, a possible etiology of tinnitus. Veterans are exposed to high levels of noise during military service. Therefore, synaptopathy may explain the high rates of noise-induced tinnitus among Veterans. Although synaptopathy cannot be directly evaluated in living humans, animal models indicate that several physiological measures are sensitive to synapse loss, including the auditory brainstem response (ABR), the middle ear muscle reflex (MEMR), and the envelope following response (EFR). The purpose of this study was to determine whether tinnitus is associated with reductions in physiological correlates of synaptopathy that parallel animal studies.

Method:

Participants with normal audiograms were grouped according to Veteran status and tinnitus report (Veterans with tinnitus, Veterans without tinnitus, and non-Veteran controls). The effects of being a Veteran with tinnitus on ABR, MEMR, and EFR measurements were independently modeled using Bayesian regression analysis.

Results:

Modeled point estimates of MEMR and EFR magnitude showed reductions for Veterans with tinnitus compared with non-Veterans, with the most evident reduction observed for the EFR. Two different approaches were used to provide context for the Veteran tinnitus effect on the EFR by comparing to age-related reductions in EFR magnitude and synapse numbers observed in previous studies. These analyses suggested that EFR magnitude/synapse counts were reduced in Veterans with tinnitus by roughly the same amount as over 20 years of aging.

Conclusion:

These findings suggest that cochlear synaptopathy may contribute to tinnitus perception in noise-exposed Veterans.

Supplemental Material:

https://doi.org/10.23641/asha.24347761
Supporting Mental Health in People Living With Aphasia: A Call to Action
Authors: Strong Katie A.
Published: October 2023

Purpose:

This clinical focus article will provide an overview of the psychosocial impact of aphasia, with particular attention to depression and anxiety and barriers for accessing mental health services. The importance of interdisciplinary collaboration between speech-language pathologists (SLPs) and mental health providers as well as importance of stepped psychological care, peer befriending, support groups, and communication partner training will be highlighted. Resources will be provided for clinicians to utilize in increasing their knowledge and skills in supporting psychosocial issues for people with aphasia and their families.

Conclusions:

People living with aphasia are at high risk of mental health problems. There is a gap in the need for services and access to services due to the inherent language challenges caused by aphasia. SLPs need to take a leadership role in bridging this gap by partnering with mental health providers to increase access to services. Using the framework of stepped psychological care, SLPs can support people living with aphasia and their families in successfully living with aphasia.
Generation of the Single Chain Antibody Fragment Conserves the Idiotypic Profile of the Anti‐CD30 Monoclonal Antibody HRS3
Authors: HOMBACH A. , POHL C. , HEUSER C , SIRCAR R, , KOCH D. , DIEHL V. , ABKEN H.
Published: October 2023

Recombinant single chain antibody fragments (scFv) derived by combining immunoglobulin VL and VH regions provide valuable antibody‐like reagents. A number of them are shown to have retained the antigen specificity of the parental monoclonal antibody (MoAb). Little is known about the idiotypic profile of scFv fragments compared with that of the parental MoAb. To address this question we analysed the idiotypic profile of a scFv that was derived by phage‐display techniques from the anti‐CD30 MoAb HRS3.We assayed (i) binding of HRS3‐scFv to recombinant CD30‐Fc antigen and to four different anti‐idiotypic MoAbs defining at least three different idiotopes on HRS3, and (ii) cross‐competition with the parental MoAb HRS3 and the closely related anti‐CD30 MoAb HRS4. The assays revealed that the HRS3‐scFv fragment exhibits the same specificity for both CD30 antigen and the tested anti‐idiotypic MoAbs compared with the parental MoAb demonstrating that the recombinant scFv fragment has retained the complete idiotope of the parental MoAb.
Bit‐Sliced Implementation of SM4 and New Performance Records
Authors: Miao Xin , Li Lu , Guo Chun , Wang Meiqin , Wang Weijia
Published: October 2023

SM4 is a popular block cipher issued by the Office of State Commercial Cryptography Administration (OSCCA) of China. In this paper, we use the bit‐slicing technique that has been shown as a powerful strategy to achieve very fast software implementations of SM4. We investigate optimizations on two frontiers. First, we present a more efficient bit‐sliced representation for SM4, which enables running 64 blocks in parallel with 256‐bit registers. Second, we describe an optimized algorithm for data form transformations, also allowing efficient implementations of SM4 under Counter (CTR) mode and Galois/Counter mode. The above optimizations contribute to a significant performance gain on one core compared with the state‐of‐the‐art results. This work is an extension of the conference paper at Inscrypt 2022, awarded the best paper award.
Study on Seismic Performance of Cold-Formed Thin-Walled Steel-Straw Board Composite Wall with Diagonal Brace
Authors: Li Linjun , Lei Jiiisong
Published: October 2023

The composite wall studied in this paper is based on the original cold-fonned thin-walled steel-straw board composite wall, which is set up with inclined braces and rigid inclined braces to improve its seismic performance. The factors of aspect ratio are analyzed, and the formula of shear bearing capacity of composite wall is deduced. The results show that: (1) When the height-width ratio of the composite wall is 2.4m×1.2m, 1.8m×1.2m and 1.2m×1.2m respectively, the yield strength of the composite wall is 35.78kN, 37.47kN and 54.23kN respectively. The yield strength of the former increases by 4.72 %, and the yield str ength of the latter increases by 44.73 %. (2) Using the effective strip method, the error of the derived shear capacity formula is not large, and the difference between the experimental value and the simulated value is not large, in order to provide some reference for the seismic design of this kind of cold-fonned thin-walled steel-strawboard composite wall with diagonal brace.
Evaluating the Properties of Self-healing Concrete: A Review
Authors: Damodaran Pooja , Thangasamy Lakshmi , Venugopal Jaganathan
Published: October 2023

The development of cracks is a regular phenomenon that causes water and various chemicals to seep into the structure reducing the strength and longevity of the building. The intrusion of external materials might affect the reinforcements when exposed to moisture and CO2 exposure, degrading the structure. Regular maintenance and treatments are needed to fix the cracks and maintain the structure. Research is in progress identifying solutions to these issues with active and self-processes in concrete which aids in repairing the cracks by generating calcium carbonate (CaCO3) particles which could seal the porosity of concrete and micro-cracks. Various bacteria like Bacillus pasteurii, Bacillus subtilis, Bacillus cohnii and Bacillus sphaericus are chosen for the crack sealing treatment as those bacteria could survive in an alkaline medium. Distinct species of bacteria have various growth conditions. Bacterial self-healing treatments were situated in an environment containing various minerals and chemicals at a constant temperature and for a specific amount of time to develop healing properties. This paper investigates the different experimental works studied on self-healing processes in large concrete samples with different sizes and materials. Studies revealed that bacteria enhanced the systemic toughness, flow ability, durability, and flexural modulus of normal concrete. This paper also investigates the different mathematical formulations established to examine the stress-strain behaviour of bacterium, which has been utilized to increase the strength of concrete.
Investigation of the Optimum Shotcrete Mixing Ratio for Slope Protection using Fly Ash
Authors: Kel Win Thang , Mohd Pauzi Nur Irfah
Published: October 2023

Shotcrete has now grown in popularity and can replace cast-in-place (CIP) concrete in applications such as retaining walls and slope stabilisation. However, due to the problems like cracking due to shrinkage and the durability concern, this practise is still limited. So, cementitious material such as fly ash is used in this situation to increase the strength of the concrete and also to make sure it is high durability and safe to use in construction. Fly ash can be known as a coal combustion residual which is commonly occur in thermal power plant and it had been widely used as an alternative material during the production of Portland cement concrete. Supplementary cementitious materials is widely used in the mixing of concrete due to its unique properties which can harden the concrete via its hydraulic and pozzolanic activity. A series of experiments will be conducted to make sure that the fly ash that had been mixed with Portland cement is safe to use and also can increase the compressive strength of the cement. Throughout the experiments, a series of data will be display with the addition of 5%,10%,15%,20%,25%,30%,35% of pozzolans in the cement mixing ratio. The addition of fly ash during the mixing of concrete will indirectly reduce the cost of construction and also the rate of pollution to the environment as it is being classified as a scheduled waste in Malaysia according to the Environmental Quality Act 1974.This research will mainly focus on the performance of shotcrete with the addition of cementitious material which is fly ash as an alternative product compare to the tradition concrete and compare the differences in the achievement of shotcrete with and without the addition of fly ash so that the comparison is more clearly and more understandable. Next, the utilization of the nominal aggregates will be 10-20mm.The amount of fly ash added to the mixing of concrete will be in the range of 5% to 35%.
Evaluation of an Innovative Case Management Strategy to Improve
Rehabilitation Coverage for People at High Risk of Permanent Work Disability: a
Feasibility Study
Authors: Remus Lea , Grope Marei , Lemke Stella , Bethge Matthias
Published: October 2023

PurposeOur process evaluation (trial registration: DRKS00022468) monitored
the implementation of a multi-component strategy including case management
aiming to improve rehabilitation coverage and work participation of people with
a high risk of permanent work disability.

Methods A risk score using administrative data, particularly on employment
and welfare benefits, was employed to identify individuals with higher
probability of receiving disability pension and therefore potentially needing
support. These individuals were contacted by post and encouraged to phone their
regional case manager if they needed assistance. Content for the intervention
components was developed collaboratively with the case managers. We examined the
sample reached, dose delivered, fidelity, dose received and satisfaction with
the intervention.

Results Out of 1074 individuals with high-risk scores were contacted,
there were 57 case managements. The participants reached were in poor health,
and 42.1% reported at least four diagnosed conditions, mostly
musculoskeletal and mental disorders. About two-thirds (63.0%) reported
poor work ability at baseline. On average, 72.5% of the content of the
initial telephone contacts, 88.7% of the content of the face-to-face
interviews and 45.2% of the content of the case management were
delivered. The participants were highly satisfied with the various components
and content of the intervention. Knowledge about rehabilitation improved
significantly, with 43 of the 57 participants (75.4%) applying for
rehabilitation, mainly medical rehabilitation. At the end of the case management
intervention, most participants (91.7%) were still employed.

Conclusion The risk score offers an opportunity to screen for people with
a high risk of permanent work disability. Case management participants found
participation worthwhile and were significantly better informed about
participation services after completing case management. More than every second
participant received medical or vocational rehabilitation.
Evaluation of Hip Characteristics in Baseball and Softball Athletes
with and Without Throwing Arm Pain
Authors: Oliver Gretchen D , Fava Anthony , Lozowski Billy , Zaremski Jason L , Holtz Kaila A , Bowers Robert L
Published: October 2023

During throwing, the lower extremity assists in the generation and transfer of
momentum. Lower extremity stability assists in this transfer by providing a base
for distal mobility of the arm segments. This study aimed to determine
differences between hip rotational range of motion and strength based on the
presence of throwing-arm pain (yes/no) and throwing sport
(baseball/softball). We hypothesized those experiencing pain would
display decreases in hip range of motion and strength, and that softball players
would display greater range of motion than baseball, but less strength based on
sex-specific characteristics. Forty-four baseball (13±2 years,
165.2±13.0 cm, 58.5±13.4 kg) and 50 softball
players (13±2 years, 160.9±11.2 cm,
62.7±17.9 kg) participated. Multivariate analysis of variance
tests (2×2) determined differences in bilateral hip range of motion,
total arc of motion, and strength between pain status and sport. There were no
significant interactions (>0.05) for pain status and sport on hip range
of motion, total arc of motion, and strength. Furthermore, no significant main
effects (>0.05) were found for pain status or sport alone on range of
motion or strength. Future work should be directed at explaining the effects of
hip characteristics on the throwing motion and how it equates to throwing-arm
health.
Cluster Preface: Modern Boron Chemistry: 60 Years of the ­Matteson Reaction
Authors: Morken James P. , Aggarwal Varinder
Published: October 2023

James P. Morken (left) was born in Concord, California (USA) and obtained his B.S. in chemistry in 1989 from UC Santa Barbara (USA) working with Prof. Bruce Rickborn. He obtained his Ph.D. from Boston ­College (USA) in 1995 with Prof. Amir Hoveyda and was an NSF ­Postdoctoral Fellow with Prof. Stuart Schreiber at Harvard University (USA). In 1997, he became an Assistant Professor of Chemistry at the University of North Carolina at Chapel Hill (USA). He was promoted to Associate Professor in 2002 and in 2006 joined the faculty of Boston College (USA). In 2014, he was named the Louise and James Vanderslice and Family Chaired Professor of Chemistry at Boston College. Professor Morken’s research focuses on the development of transition-metal-­catalyzed asymmetric processes and their use in complex molecule synthesis. He is particularly interested in the study and development of catalytic enantioselective reactions involving organoboron reagents.

Varinder K. Aggarwal (right) studied chemistry at Cambridge University and received his Ph.D. in 1986 under the guidance of Dr. Stuart ­Warren. After postdoctoral studies under Prof. Gilbert Stork at Columbia University (1986–1988), he returned to the UK as a lecturer at Bath University. In 1991, he moved to Sheffield University, where he was promoted to professor in 1997. In 2000, he moved to Bristol University, where he holds the Chair in Synthetic Chemistry. His research interests include the development of new catalytic processes for asymmetric synthesis, the development of chiral carbenoids and their use and subsequent applications in catalysis and synthesis, and the development of new methodology and its applications in synthesis and the total synthesis of biologically important targets.
Navigating the terrain of caregiving of children with intellectual and developmental disabilities: importance of benefit finding and optimism
Authors: Jamir Singh Paramjit Singh , Azman Azlinda , Drani Syazwani , Mohd Nor Mohd Iqbal Haqim , Che Ahmad Aznan
Published: October 2023

Empirical studies have indicated that benefit finding and optimism greatly help caregivers of children with intellectual or developmental disabilities. Specifically, it has been suggested that these two constructs serve as critical coping strategies for those engaged in the caregiving process. Here, a qualitative study was undertaken to explore the impacts of benefit finding and optimism on caregivers of children with intellectual and developmental disabilities in Malaysia. Twenty (20) caregivers of children with intellectual and developmental disabilities were interviewed concerning their perception and use of benefit finding and optimism. Results identified these strategies as supporting and guiding caregiving responsibilities and skills, improving personal growth, relationships and spirituality, as well as increasing positive perceptions. Therefore, policymakers and stakeholders in Malaysia should implement targeted interventions to facilitate and support caregivers in applying benefit-finding and optimism in their caregiving, thereby assisting them to better cope with the physical and mental demands of caring for children with intellectual and developmental disabilities.
Evidence of ferromagnetic coupling for manganese pairs in a layered van der Waals GaS semiconductor
Authors: Babunts Roman A. , Batueva Anastasia V. , Gurin Alexander S. , Likhachev Kirill V. , Edinach Elena V. , Baranov Pavel G.
Published: October 2023

Using high-frequency electron paramagnetic resonance (EPR), we have observed the ferromagnetic coupling of manganese Mn2+ pairs in a layered van der Waals GaS semiconductor. The EPR spectra of Mn2+ pairs (Mn24+) [replacing covalently bonded Ga24+ pairs oriented along the chain axis (c axis) of two gallium ions and being situated in the center of the layer] were recorded at 94 and 130 GHz. The fine structure parameters for the lower multiplets with spin S = 5 and S = 4 were determined equal to D = −0.040 cm−1 and D ≅ −0.035 cm−1, respectively. Based on the observation of additional EPR lines in the region of intersection of the levels in the magnetic field of the multiplet with S = 5 and S = 4, the energy of the isotropic exchange interaction J was estimated to be ∼−0.5 cm−1. For all transitions, a well-resolved hyperfine structure was observed, due to the interaction with two equivalent 55Mn nuclei, leading to the appearance of 11 lines with a hyperfine interaction constant A = 30(1) × 10−4 cm−1, which is approximately half the hyperfine interaction constant for single Mn2+ ions. In addition, a signal from single manganese ions Mn2+ with spin S = 5/2 and a hyperfine interaction constant A = 60(1) × 10−4 cm−1 was observed, which are characterized by extremely large fine structure splitting of D = −0.15 cm−1. Simultaneously with EPR studies, the crystals were monitored by photoluminescence and micro-Raman scattering measurements using a microscope with confocal optics.
Impact of cooling rate and shear flow on crystallization and mechanical properties of wax-crystal networks
Authors: Werner-Cárcamo Erwin R. , Rubilar Mónica , Macias-Rodriguez Braulio A. , Marangoni Alejandro G.
Published: October 2023

Wax oleogels are one of the most promising strategies to produce trans-fat free and low-saturate functional fats. Under quiescent isothermal conditions, waxes form strong space-filling networks where oil is embedded. Nevertheless, in industrial processes, crystallization conditions deviate significantly from being isothermal and quiescent, yet these far from equilibrium conditions have received limited attention in the literature. Cooling and shear rate gradients during crystallization can promote molecular alignment, crystal growth, and crystal network reorganization that hold the potential to tune the mechanical properties of oleogels. Therefore, this study aimed to investigate the impact of different controlled cooling and shear rates during the crystallization process of beeswax oleogels. An analysis of both small and large amplitude oscillatory shear was conducted to understand the linear and nonlinear mechanical properties of oleogels. Additionally, microscopic/macroscopic analyses, including oil-binding capacity, were performed. The results indicate that sheared oleogels display plastic-like behavior, lower linear elastic moduli, and a higher perfect plastic dissipation ratio than oleogels cooled under quiescent conditions, which displayed stiff, brittle-like characteristics. In addition, these oleogels displayed a microstructure with smaller crystals than oleogels cooled under quiescent conditions. This phenomenon can be attributed to a transition of oleogels from a strong, yet brittle interconnected particle network, to a dispersion of jammed crystal particles that align more easily along the direction of flow, resulting in minimal additional contribution from viscous stress after yielding. Therefore, a controlled cooling and shear rate application is an effective method to tune the mechanical properties of wax oleogels.
On the Herglotz variational problem
Authors: Massa Enrico , Pagani Enrico
Published: October 2023

A geometric approach to the Herglotz problem is developed, based on the bundle of affine scalars on the configuration manifold of the given system. The environment, originally introduced to formalize the gauge structure of Lagrangian Mechanics [E. Massa, E. Pagani, and P. Lorenzoni, Transp. Theory Stat. Phys. 29, 69 (2000)], provides the natural setting for the representation of the Herglotz functional as well as for the study of its extremals. Various aspects of the problem are considered: the Lagrangian approach, leading to a generalization of the Poincaré-Cartan algorithm; the parametric approach, involving the introduction of an appropriate super-Lagrangian; the corresponding Hamiltonian and super-Hamiltonian counterparts; the relationship between the Herglotz problem and a constrained variational problem; the evaluation of the abnormality index [Massa et al., Int. J. Geom. Methods Mod. Phys. 12, 1550061 (2015)] of the resulting extremals; the gauge structure of the theory and the consequent existence of Herglotz’s functionals gauge-equivalent to ordinary action functionals.
Three-dimensional shear-flow instability saturation via stable modes
Authors: Tripathi B. , Terry P. W. , Fraser A. E. , Zweibel E. G. , Pueschel M. J.
Published: October 2023

Turbulence in three dimensions (3D) supports vortex stretching that has long been known to accomplish energy transfer to small scales. Moreover, net energy transfer from large-scale, forced, unstable flow-gradients to smaller scales is achieved by gradient-flattening instability. Despite such enforcement of energy transfer to small scales, it is shown here that the shear-flow-instability-supplied 3D-fluctuation energy is largely inverse-transferred from the fluctuation to the mean-flow gradient, and such inverse transfer is more efficient for turbulent fluctuations in 3D than in two dimensions (2D). The transfer is due to linearly stable eigenmodes that are excited nonlinearly. The stable modes, thus, reduce both the nonlinear energy cascade to small scales and the viscous dissipation rate. The vortex-tube stretching is also suppressed. Up-gradient momentum transport by the stable modes counters the instability-driven down-gradient transport, which also is more effective in 3D than in 2D (≈70% vs ≈50%). From unstable modes, these stable modes nonlinearly receive energy via zero-frequency fluctuations that vary only in the direction orthogonal to the plane of 2D shear flow. The more widely occurring 3D turbulence is thus inherently different from the commonly studied 2D turbulence, despite both saturating via stable modes.
On the unsteady interactions between a sweeping jet and afterbody vortices
Authors: Chen Xiaodong , Zhong Shan , Ozer Ozgun , Weightman Andrew , Gao Guangjun
Published: October 2023

In this paper, a sweeping jet was applied to control the afterbody vortices behind a 30° slanted-base cylinder at a Reynolds number of 87 000. Phase-locked stereo particle image velocimetry measurements were conducted during a sweeping jet actuation cycle, and insights of the complex three-dimensional interaction process between the sweeping jet and the afterbody vortices have been obtained for the first time. It is found that in the near-field of the jet orifice (x/c < 0.3), the jet swings from side to side over the endplate between the afterbody vortex pair. An intersection between them around x/c = 0.3 causes the sweeping jet to take on a zigzag pattern as it propagates downstream along the slanted surface. From x/c = 0.6 onwards, the intensity of this interaction decreases as the afterbody vortices become detached from the base. Nevertheless, the sweeping jet continues invading the afterbody vortices from their inner side and pushes its way outwards from the underside of the afterbody vortices causing them to weaken further. Furthermore, the interaction between sweeping jets and afterbody vortices results in a cyclic variation in the circulation of afterbody vortices, which increases in magnitude at downstream locations. Except for the phases where a merger between the afterbody vortex and the sweeping occurs, a reduction in the circulation is observed. Finally, the level of interaction between sweeping jets and afterbody vortices intensifies as the strength of the sweeping jet increases resulting in the afterbody vortices being penetrated by the sweeping jet and their regular shape being momentarily destroyed.