Alternative Mechanisms Research Articles

No such thing as waste in primary food sector.

The European Union (EU) circular economy action plan aims to double its use of recycled material by 2030. We argue that waste-centric approach to resources may have adverse consequences to this ambition. The aim of the work was to find out the factors limiting or promoting the use of waste from primary food sector in countries with the same cultural background and similar climate in Estonia, Latvia, Lithuania and Norway. Biomass from the primary food production sector is of good quality and excellent to use, but its use may be limited if given waste status. From numerous management decision trigger clusters, which may affect valorisation of the biomass, we focus on technology and policy. Our semi-structured interviews addressed the analysis and management of waste or by-products and explored the end-of-waste and alternative mechanisms that allowed the biomass to be valorised. However, the interviews revealed that none of the companies regard anything becoming waste, but as raw material or production left-over. Any obstacles hypothesised turned out not to be acknowledged by companies at all. This appears to be a very good example of the use of resources, but the approach is haphazard and may conflict with official understanding and waste reporting requirements. Definition of waste is the same in the EU, and arbitrary treatment can be misleading. There is a need for better management of the material flow to ensure effective biomass circulation avoiding its becoming waste. We recommend that this be addressed by introducing environmental, social, governance and a self-control system.

Multiple Effects of L-Leucine in Escherichia coli Lead to L-Leucine-Sensitive Growth in the Absence of Unphosphorylated PtsN.

In E. coli K-12, the absence of unphosphorylated PtsN (unphospho-PtsN) has been proposed to cause an L-leucine-sensitive growth phenotype (LeuS) by hyperactivated K+ uptake mediated impairment of the expression of the ilvBN operon, encoding subunits of the L-valine (Val)-sensitive acetohydroxyacid synthase I (AHAS I) that renders residual AHAS activity susceptible to inhibition by Leu and K+. This leads to AHAS insufficiency and a requirement for L-isoleucine (Ile). Herein, we provide an alternate mechanism for the LeuS of the ∆ptsN mutant. Genetic and physiological studies with suppressors of the LeuS indicate that impaired expression of the ilvBN operon jointly caused by the absence of unphospho-PtsN and the presence of Leu coupled to Leu-mediated repression of expression of AHAS III leads to AHAS insufficiency rendering residual AHAS activity susceptible to chronic Val stress that may be generated by exogenous Leu. Hyperactivated K+ uptake and an elevated α-ketobutyrate level mediate elevation of ilvBN expression and alleviate the LeuS. The requirement of unphospho-PtsN as a positive regulator of ilvBN expression may buffer Ile biosynthesis against Leu-mediated AHAS insufficiency and protect AHAS I function from chronic endogenous Val generated by Leu and could be realized in certain environments that impair AHAS function.

Non-homogeneous anisotropic bulk viscosity for acoustic wave attenuation in weakly compressible methods

A major limitation of the weakly compressible approaches to simulate incompressible flows is the appearance of artificial acoustic waves that introduce mass conservation errors and lead to spurious oscillations in the force coefficients. In this work, we propose a non-homogeneous anisotropic bulk viscosity term to effectively damp the acoustic waves. By implementing this term in a computational framework based on the recently proposed general pressure equation, we demonstrate that the non-homogeneous and anisotropic nature of the term makes it significantly more effective than the isotropic homogeneous version widely used in the literature. Moreover, it is computationally more efficient than the pressure (or mass) diffusion term, which is an alternative mechanism used to suppress acoustic waves. We simulate a range of benchmark problems to comprehensively investigate the performance of the bulk viscosity on the effective suppression of acoustic waves, mass conservation error, order of convergence of the solver, and computational efficiency. The proposed form of the bulk viscosity enables fairly accurate modelling of the initial transients of unsteady simulations, which is highly challenging for weakly compressible approaches, and to the best of our knowledge, existing approaches can't provide an accurate prediction of such transients.

Molecular detection of OXA-48 and NDM-1 carbapenemase genes among clinical isolates of Klebsiella pneumoniae recovered from patients attending a private tertiary hospital in Southwestern Nigeria

There have been increasing reports of Klebsiella pneumoniae resistant to β-lactam antibiotics. This study aimed to determine the prevalence of some selected carbapenemase genes among clinical isolates of Klebsiella pneumoniae recovered from patients attending a private tertiary hospital in Southwestern Nigeria. The study was conducted over two months (February-March 2024). A total of 50 clinical isolates of Klebsiella pneumoniae from different clinical specimens were obtained from the Medical Microbiology Department, Babcock University Teaching Hospital (BUTH). The clinical isolates were then characterized using standard microbiological procedures and were tested for susceptibility to meropenem and other classes of antibiotics according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Polymerase Chain Reaction (PCR) detection for OXA-48 and NDM-1 carbapenemase genes was performed on the 50 clinical isolates. PCR analysis showed that 9 (18%) clinical isolates were positive for the OXA-48 gene, 22 (44%) were positive for the NDM-1 gene, 4 (8%) possessed both the OXA-48 and NDM-1 genes, and 23 (46%) possessed neither the OXA-48 nor NDM-1 genes. Antibiotic Susceptibility Testing (AST) revealed that all the clinical isolates were resistant to meropenem. In conclusion, this study demonstrates the presence of OXA-48 and NDM-1 genes in clinical isolates of Klebsiella pneumoniae recovered from patients attending a private tertiary hospital in Southwestern Nigeria, highlighting the role of ESBL (extended-spectrum beta-lactamase) as a major resistance mechanism alongside other mechanisms. Population-based surveillance programs should be implemented to monitor the prevalence and epidemiology of Klebsiella pneumoniae infections at the community level, facilitating early detection of outbreaks and identification of emerging antimicrobial resistance patterns.Core TipThis study highlights the significant prevalence of NDM-1 and OXA-48 carbapenemase genes among Klebsiella pneumoniae clinical isolates in a private tertiary hospital in Southwestern Nigeria, with 44% and 18% of isolates harboring these genes, respectively. Notably, 46% of isolates were resistant to carbapenems despite lacking these genes, suggesting alternative resistance mechanisms. The findings underscore the urgent need for enhanced surveillance, infection control measures, and antibiotic stewardship programs to combat the spread of multidrug-resistant Klebsiella pneumoniae in healthcare settings.

Collaborations with nonprofit organizations: Signals or agents of operational change? Empirical evidence from Italian listed enterprises

AbstractCollaborations with nonprofits are an avenue for firms to tackle social and environmental issues, and their disclosure is one way through which firms can inform stakeholders of the sustainability of their operations. This paper investigates their signaling function, disentangling it from their transformative role in spurring sustainable operational changes. Econometric analyses on collaborations reported by 118 Italian listed firms in their non‐financial disclosures in 2017–2019 confirm their signaling function. Most reported collaborations do not imply firms' operational engagements. Firms' propensity to collaborate is higher when their activities are less observable, institutional monitoring is weak, and alternative signaling mechanisms are absent. However, signaling determinants are weaker when collaborations involve firm‐level operational engagements. The study offers exploratory evidence that firms disclose collaborations with nonprofits as signals of sustainability. It offers insights on their dual role, showing that collaborations which spur sustainable operational changes are less likely to be employed as signals.

The role of digital arbitration in the resolution of electronic commerce disputes between the necessity of application and the imperative of confrontation

The world has recently undergone a major shift in international information technology, software and communications, which has been regarded as a global revolution in many areas. and transformed traditional means of commercial transactions into electronic means of communication through the promotion, exchange and completion of transactions of goods using modern telecommunications and information exchange technology without the parties meeting in one place, Whether mutual commitments can be implemented electronically or require concrete physical implementation which created for us e-commerce that has become a reality of a real pension, It is also one of the economic pillars of the State and an important mechanism for raising productivity. This necessitates the provision of the appropriate legal environment and the search for means to ensure that they are controlled within a systematic and regulated legal framework, In particular, contracts involving international parties via the Internet require delving into private international law, the determination of the judicial area for the resolution of electronic commerce disputes and the determination of applicable law was a major burden on parties and States, which prompted their clients to seek alternative electronic mechanisms to replace traditional courts to settle disputes resulting from the use of electronic media in their commercial transactions, so-called ODR dispute resolution. s electronic teleconference, this has made recourse to electronic or digital arbitration as a virtual judge system a requirement of many international organizations and associations. The forms raised: how effective is digital or electronic arbitration in resolving e-commerce disputes? We therefore divide our research into two sections, dealing with section I: the conceptual framework for electronic commerce as well as digital electronic arbitration, and section II: the role of digital arbitration in the termination and resolution of e-commerce disputes.

NTRK Fusion as an Acquired Mechanism of Resistance to Selpercatinib in RET Positive Thyroid Cancer

Background: Rearrangement during Transfection (RET) proto-oncogene is involved in the pathogenesis of various thyroid cancer subtypes and drugs that block the RET tyrosine kinase pathways are used in the management of locally advanced and metastatic Medullary Thyroid Cancer (MTC). Acquired resistance to RET inhibitors likely occurs via two different mechanisms: (1) On-target mutations that prevent drug binding and (2) Activated alternative mechanisms which bypass the targeted kinase. We present a unique mechanism of selpercatinib resistance via secondary NTRK fusion mutation in a case of RET altered medullary thyroid cancer. Case Presentation: The patient is a 72-year-old female with stage III metastatic MTC who developed recurrence with newly found RET mutation 7 years after complete surgical resection. Despite initial stable response with selpercatinib for 2 years she rapidly progressed with widespread disease. Cell-free DNA (cfDNA) testing done at the time of progression revealed an NTRK1 fusion. Unfortunately, the patient succumbed to the disease despite starting targeted therapy with larotrectinib. Conclusion: This case highlights the importance of further investigation into mechanisms of resistance to RET inhibitors and drug studies directed towards overcoming them

The Multiple Resource Theory and Model. Some Misconceptions in Data Interpretations

Multiple Resource Theory, and one particular instantiation of the theory in the 4-Dimensional Multiple Resource Model have often been invoked as mechanisms to account for dual task interference. Here we present the data and analyses requirements necessary to conclude that the multiple resource model either does or does not predict an increase in the dual task decrement; and in particular we describe the need to consider and control both task difficulty and task priority in comparing conditions that are argued to contrast shared versus separate resources. We then consider one common misconception regarding what the model predicts regarding perfect time sharing, and address the importance of considering alternative theory-based mechanisms of task switching and of confusion and crosstalk, to account for patterns of multi-task interference.

Genotype-specific morphophysiological adaptations and proline accumulation uncover drought adaptation complexity in hemp (Cannabis sativa and Cannabis indica)

Hemp, which has a wide range of industrial applications, has been marginalized due to its association with marijuana. This stigma has hindered research into improving its resilience to various stressors, resulting in underutilization and neglect. As cultivation expands globally, particularly in hot, dry regions of Africa, understanding drought stress mechanisms in hemp is crucial. This study investigates the drought adaptation mechanisms of three CBD flower hemp genotypes: Cannabis indica (MP) from Switzerland, Cannabis sativa (AQ) from South Africa, and Cannabis sativa (ZB) from Zimbabwe. Conducted under well-watered (WW-75% field capacity [FC]), mild drought (MD-40% FC), and severe drought (SD-0% FC) conditions, the research examines morphophysiological adaptations and proline accumulation in these genotypes, assessed 55 days after transplanting. Results revealed genotype-specific responses to watering regimes. MP demonstrated controlled water use and inherent drought tolerance, maintaining high assimilation rates (A) and superior photosynthetic performance (ΦPSII) under drought conditions. ZB maintained proline levels during drought recovery, suggesting optimized resource allocation and alternative stress-responsive mechanisms, while exhibiting effective morning water use and high non-photochemical quenching (NPQ) for photoprotection. AQ showed conservative water use strategies beneficial in water-limited environments. These findings provide a foundation for breeding programs aimed at developing robust and resilient hemp varieties suited to specific environmental conditions.

Contact-Map-Driven Exploration of Heterogeneous Protein-Folding Paths.

We have recently shown how physically realizable protein-folding pathways can be generated using directed walks in the space of inter-residue contact-maps; combined with a back-transformation to move from protein contact-maps to Cartesian coordinates, we have demonstrated how this approach can generate protein-folding trajectory ensembles without recourse to molecular dynamics. In this article, we demonstrate that this framework can be used to study a challenging protein-folding problem that is known to exhibit two different folding paths which were previously identified through molecular dynamics simulation at several different temperatures. From the viewpoint of protein-folding mechanism prediction, this particular problem is extremely challenging to address, specifically involving folding to an identical nontrivial compact native structure along distinct pathways defined by heterogeneous secondary structural elements. Here, we show how our previously reported contact-map-based protein-folding strategy can be significantly enhanced to enable accurate and robust prediction of heterogeneous folding paths by (i) introducing a novel topologically informed metric for comparing two protein contact maps, (ii) reformulating our graph-represented folding path generation, and (iii) introducing a new and more reliable structural back-mapping algorithm. These changes improve the reliability of generating structurally sound folding intermediates and dramatically decrease the number of physically irrelevant folding intermediates generated by our previous simulation strategy. Most importantly, we demonstrate how our enhanced folding algorithm can successfully identify the alternative folding mechanisms of a multifolding-pathway protein, in line with direct molecular dynamics simulations.

Do the specific characteristics of female directors work as alternative governance mechanisms to restrict earnings management in a developing country?

AbstractThis inquiry probes whether or not female directors and their specific characteristics effectively restrict earnings management (EM) measured by accrual‐based earnings management (AEM) and real‐based earnings management (REM) in a sample of 217 Pakistani companies from 2016 to 2021. The outcomes of the ordinary least squares with panel corrected standard errors demonstrated that boards with female directors are more effective in restricting EM than others. The results also explain that the proportion of female directors on the board and audit committee and the experience of the former are significantly and inversely associated with AEM and REM. However, women directors should be at least two or more on the board to effectively control AEM and REM since the role of a lone female director is insignificant in their mitigation. The positive effect of the female directors' master's or above qualification is slightly higher than their bachelor's or below education in opposing AEM and REM. Furthermore, the business education of female directors significantly, while their non‐business education insignificantly reduces AEM and REM. The findings are consistent and reliable for being validated by the generalised method of moments as an alternative estimator. Overall, the inquiry complements the literature, theory, practice, and policy in several ways.

Phenobarbital as an adjunctive agent for sedation in pediatric intensive care unit patients: A single-center, retrospective study from Colorado

Abstract Background: Pediatric patients require pharmacological management of pain and agitation associated with mechanical ventilation. Pain and agitation may be refractory to opioids and alpha-2 agonists, prompting the use of adjunctive analgesics and sedatives with alternative mechanisms. The purpose of this study was to describe the use of phenobarbital as an adjunctive agent for refractory agitation in critically ill, mechanically ventilated pediatric patients. Subjects and Methods: This was a single-center, retrospective chart review at a pediatric intensive care unit (PICU) at a pediatric academic medical center in America between 2016 and 2021. Children aged 2 months to 18 years old were admitted to the PICU were mechanically ventilated and received phenobarbital for adjunct sedation. Sixty-three patients had phenobarbital dosing data evaluated, and the 38 patients who were not receiving continuous neuromuscular blockade were included in the primary and secondary outcome analysis of time within the goal sedation score. Descriptive statistics was used to assess baseline characteristics and the primary outcome. Wilcoxon signed-rank tests were used to evaluate secondary outcomes. Results: Patients spent significantly more time within the goal sedation score range after phenobarbital compared to before phenobarbital. The median number of rescue sedative boluses, morphine equivalents (MEs), and benzodiazepine equivalents (BZDE) significantly decreased 2 days after the first phenobarbital dose compared to the 2 days before the first phenobarbital dose. Conclusions: The use of phenobarbital as an adjunct sedative was associated with a statistically significant increase in time spent in the goal sedation score range and decrease in ME, BZDE, and concomitant sedative boluses.

The influence of context on diagnostic reasoning: A narrative synthesis of experimental findings.

Contextual information which is implicitly available to physicians during clinical encounters has been shown to influence diagnostic reasoning. To better understand the psychological mechanisms underlying the influence of context on diagnostic accuracy, we conducted a review of experimental research on this topic. We searched Web of Science, PubMed, and Scopus for relevant articles and looked for additional records by reading the references and approaching experts. We limited the review to true experiments involving physicians in which the outcome variable was the accuracy of the diagnosis. The 43 studies reviewed examined two categories of contextual variables: (a) case-intrinsic contextual information and (b) case-extrinsic contextual information. Case-intrinsic information includes implicit misleading diagnostic suggestions in the disease history of the patient, or emotional volatility of the patient. Case-extrinsic or situational information includes a similar (but different) case seen previously, perceived case difficulty, or external digital diagnostic support. Time pressure and interruptions are other extrinsic influences that may affect the accuracy of a diagnosis but have produced conflicting findings. We propose two tentative hypotheses explaining the role of context in diagnostic accuracy. According to the negative-affect hypothesis, diagnostic errors emerge when the physician's attention shifts from the relevant clinical findings to the (irrelevant) source of negative affect (for instance patient aggression) raised in a clinical encounter. The early-diagnosis-primacy hypothesis attributes errors to the extraordinary influence of the initial hypothesis that comes to the physician's mind on the subsequent collecting and interpretation of case information. Future research should test these mechanisms explicitly. Possible alternative mechanisms such as premature closure or increased production of (irrelevant) rival diagnoses in response to context deserve further scrutiny. Implications for medical education and practice are discussed.

A Lab-scale Investigation of the Mars Kieffer Model

The Kieffer model is a widely accepted explanation for seasonal modification of the Martian surface by CO2 ice sublimation and the formation of a “zoo” of intriguing surface features. However, the lack of in situ observations and empirical laboratory measurements of Martian winter conditions hampers model validation and refinement. We present the first experiments to investigate all three main stages of the Kieffer model within a single experiment: (i) CO2 condensation on a thick layer of Mars regolith simulant; (ii) sublimation of CO2 ice and plume, spot, and halo formation; and (iii) the resultant formation of surface features. We find that the full Kieffer model is supported on the laboratory scale as (i) CO2 diffuses into the regolith pore spaces and forms a thin overlying conformal layer of translucent ice. When a buried heater is activated, (ii) a plume and dark spot develop as dust is ejected with pressurized gas, and the falling dust creates a bright halo. During plume activity, (iii) thermal stress cracks form in a network similar in morphology to certain types of spiders, dendritic troughs, furrows, and patterned ground in the Martian high south polar latitudes. These cracks appear to form owing to sublimation of CO2 within the substrate, instead of surface scouring. We discuss the potential for this process to be an alternative formation mechanism for “cracked” spider-like morphologies on Mars. Leveraging our laboratory observations, we also provide guidance for future laboratory or in situ investigations of the three stages of the Kieffer model.

Evaluation of the potential of infrastructure funds: The case of inland waterways in Germany

Given the critical need for sustainable transportation solutions, inland waterways (IWs) constitute a crucial yet underfunded mode of transport. This study examines deficiencies in current infrastructure funding and analyzes infrastructure funds (IFs) as an alternative funding mechanism and potential means to revitalize German waterways.Central to this investigation is the analysis of the German population's willingness to pay (WTP) for such funds. To this end, a comprehensive online survey of German households was conducted, and multivariate regression analysis was employed to identify key factors influencing public support for various fund designs.The results reveal that personal experiences with flooding significantly affect WTP and underscore the role of socio-economic variables in shaping public attitudes toward infrastructure funding. The findings indicate that well-designed IFs, combined with effective communication strategies to raise awareness of the importance of waterways, could significantly enhance public support. The study demonstrates that IFs have significant potential as a strategic tool for mobilizing public funding, thereby supporting the sustainable development and maintenance of essential yet underfunded infrastructure. IFs present a promising solution to the financial challenges facing critical public goods such as waterways.

"All we have to fear is fear itself": Paradigms for reducing fear by preventing awareness of it.

Research on unconscious fear responses has recently been translated into experimental paradigms for reducing fear that bypass conscious awareness of the phobic stimulus and thus do not induce distress. These paradigms stand in contrast to exposure therapies for anxiety disorders, which require direct confrontation of feared situations and thus are distressing. We systematically review these unconscious exposure paradigms. A Preferred Reporting Items for Systematic Reviews and Meta-Analyses-based search yielded 39 controlled experiments based on 10 paradigms that tested whether exposure without awareness can reduce fear-related responses. In randomized controlled trials of phobic participants, unconscious exposure interventions: (a) reduced behavioral avoidance (weighted mean d = 0.77, N = 469) and self-reported fear (d = 0.78, N = 329) during in vivo exposure to feared situations; (b) reduced neurobiological indicators of fear and enhanced such indicators of fear regulation (d = 0.81, N = 205); (c) had significantly stronger effects on reducing symptomatic behaviors and enhancing neurobiological indicators of fear regulation than did conscious exposure (d = 0.78, N = 342); and (d) produced these effects without inducing subjective fear. In fear-conditioned participants, unconscious exposureinduced extinction learning (d = 0.80, N = 420), even during sleep, and yielded somewhat stronger extinction learning than conscious exposure did (d = 0.44, N = 438). We organize these findings within a neuroscientific framework and evaluate alternative mechanisms for unconscious exposure. The use of incommensurate outcome measures across exposure paradigms and nonreporting of relevant statistics limited meta-analyses. Despite steps taken to address publication bias, 25.6% of included studies came from a single laboratory. We propose potential clinical applications of these findings. Future research should clarify underlying mechanisms, use common outcome measures, and explore effects on other anxiety disorders. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

In vivo measurements of change in tissue oxygen level during irradiation reveal novel dose rate dependence

Background and purposeThis study aimed to investigate the radiochemical oxygen depletion (ROD) in vivo by directly measuring oxygen levels in various mouse tissues during ultra-high dose rate (UHDR) irradiation at clinically relevant doses and dose rates. Materials and methodsMice bearing subcutaneous human glioblastoma (U-87 MG) tumors were used for tumor and normal tissue (skin, muscle, brain) measurements. An oxygen-sensitive phosphorescent probe (Oxyphor PtG4) was injected into the tissues, and oxygen levels were monitored using a fiberoptic phosphorometer during UHDR irradiation with a 6 MeV electron linear accelerator (LINAC). Dose escalation experiments (10–40 Gy) were performed at a dose rate of 1300 Gy/s, and dose rate escalation experiments were conducted at a fixed dose of 40 Gy with dose rates ranging from 2 to 101 Gy/s. ResultsRadiation-induced change in tissue oxygenation (ΔpO2) increased linearly with dose and correlated with baseline tissue oxygenation levels in the range of 0 – 30 mmHg. At higher baseline tissue oxygenation levels, such as those observed in muscle and brain, there was no corresponding increase in ΔpO2. When we modulated dose rate, ΔpO2 increased steeply up to ∼ 20 Gy/s and plateaued thereafter. The relationship between ΔpO2 and dose rate showcases the interplay between ROD and reoxygenation. ConclusionWhile UHDR irradiation induces measurable oxygen depletion in tissues, the observed changes in oxygenation levels do not support the hypothesis that ROD-induced radioresistance is responsible for the FLASH tissue-sparing effect at clinically relevant doses and dose rates. These findings highlight the need for further investigation into alternative mechanisms underlying the FLASH effect.

Adaptive Induction of Nonshivering Thermogenesis in Muscle Rather Than Brown Fat Could Counteract Obesity.

Warm-blooded animals such as birds and mammals are able to protect stable body temperature due to various thermogenic mechanisms. These processes can be facultative (occurring only under specific conditions, such as acute cold) and adaptive (adjusting their capacity according to long-term needs). They can represent a substantial part of overall energy expenditure and, therefore, affect energy balance. Classical mechanisms of facultative thermogenesis include shivering of skeletal muscles and (in mammals) non-shivering thermogenesis (NST) in brown adipose tissue (BAT), which depends on uncoupling protein 1 (UCP1). Existence of several alternative thermogenic mechanisms has been suggested. However, their relative contribution to overall heat production and the extent to which they are adaptive and facultative still needs to be better defined. Here we focus on comparison of NST in BAT with thermogenesis in skeletal muscles, including shivering and NST. We present indications that muscle NST may be adaptive but not facultative, unlike UCP1-dependent NST. Due to its slow regulation and low energy efficiency, reflecting in part the anatomical location, induction of muscle NST may counteract development of obesity more effectively than UCP1-dependent thermogenesis in BAT.

An investigation of the structure property relation of Na2MnWO6 for device application

This communication delves into the structural, microstructural, dielectric, impedance, modulus, and optical properties of the double-perovskite ceramic Na2MnWO6. Our X-ray diffraction study revealed a multiphase crystal structure in this ceramic, a result of high-temperature mixed-oxide synthesis. Morphological studies indicated a nearly uniform grain scattering and distribution with minimal spaces. The Maxwell-Wagner model, by addressing alternative polarisation mechanisms, studied the frequency-dependent dielectric properties. Our study of temperature-dependent dielectric permittivity identified a ferroelectric to paraelectric phase transition dielectric aberration. The material’s NTCR characteristic was determined using impedance analysis. Jonscher’s power law showed that the conduction mechanism follows the overlapping of large polaron tunnelling and correlated barrier hopping models, establishing the link between conductivity and frequency. Relaxation and conduction activation energies support electron hopping. UV spectroscopy revealed a band gap of 4.01 eV, and temperature-dependent resistance studies suggest a potential use in thermistors with due parameters. These findings significantly enhance our understanding of NMWO, paving the way for its potential uses in electronics and optics, owing to its unique structural, electrical, and optical features.

Pectin-like heteroxylans in the early-diverging charophyte Klebsormidium fluitans.

The cell walls of charophytic algae both resemble and differ from those of land plants. Cell walls in early-diverging charophytes (e.g. Klebsormidiophyceae) are particularly distinctive, in ways that may enable survival in environments that are incompatible with land-plant polymers. This study therefore investigates the structure of Klebsormidium polysaccharides. The 'pectin' fraction (defined by extractability) of Klebsormidium fluitans, solubilised by various buffers from alcohol-insoluble residues (AIRs), was digested with several treatments that (partially) hydrolyse land-plant cell-wall polysaccharides. Products were analysed by gel-permeation and thin-layer chromatography. The Klebsormidium pectic fraction made up ~30-50% of its AIR, was optimally solubilised at pH 3-4 at 100°C, and contained residues of xylose ≈ galactose > rhamnose > arabinose, fucose, mannose, glucose. Uronic acids were undetectable and the pectic fraction was more readily solubilised by formate than by oxalate, suggesting a lack of chelation. Some land-plant-targeting hydrolases degraded the Klebsormidium pectic fraction: digestion by α-l-arabinanase, endo-β-(1⟶4)-d-xylanase, and α-d-galactosidase suggests the presence of β-(1⟶4)-xylan with terminal α-l-arabinose, α-d-galactose and (unexpectedly) rhamnose. 'Driselase' released oligosaccharides of xylose and rhamnose (~1:1) and graded acid hydrolysis of these oligosaccharides indicated a 'rhamnoxylan' with rhamnose side-chains. Partial acid hydrolysis of Klebsormidium pectic fraction released rhamnose plus numerous oligosaccharides, one of which comprised xylose and galactose (~1:2 Gal/Xyl), suggesting a galactoxylan. Lichenase was ineffective, as were endo-β-(1⟶4)-d-galactanase, endo-β-(1⟶4)-d-mannanase, β-d-xylosidase and β-d-galactosidase. Klebsormidium pectic fraction possesses many land-plant-like linkages but is unusual in lacking uronic acid residues and in containing rhamnoxylan and galactoxylan domains. Uronic acids allow land-plant and late-diverging charophyte pectins to form Ca2+-bridges, facilitating cell-wall polymer association; their absence from Klebsormidium suggests that neutral heteroxylans rely on alternative cross-linking mechanisms. This lack of dependency on Ca2+-bridges may confer Klebsormidium's ability to grow in the acidic, metal-rich environments which it tolerates.