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• As expected, a higher volume of physical activity was associated with reduced odds of both hypertension and obesity. • When considering the volume of physical activity, the frequency or intensity of physical activity did not significantly impact the odds of hypertension. • An increased proportion of vigorous physical activity relative to the total volume was associated with a small additional reduction in the odds of obesity. • Overall, physical activity volume seems to be more important than specific patterns of accumulation for preventing hypertension and obesity in women. Optimal patterns of accrual of recommended levels of physical activity (PA) for prevention of hypertension and obesity are not known. The overall aim of this study was to investigate whether different patterns of accumulation of PA are differentially associated with hypertension and obesity in Australian women over 21 years. Specifically, we investigated whether, for the same weekly volume of PA, the number of sessions (frequency) and vigorousness of PA (intensity) were associated with a reduction in the occurrence of hypertension and obesity in women. Data from the 1973–1978 and 1946–1951 cohorts of the Australian Longitudinal Study on Women's Health were analyzed (n = 20,588; 12%–16% with a Bachelor's or higher degree). Self-reported PA, hypertension, height, and weight were collected using mail surveys every 3 years from 1998/2000 to 2019/2021. Generalized Estimating Equation models with a 3-year lag model were used to investigate the association of PA volume (metabolic equivalent min/week) (none; 33–499; 500–999; ≥1000, weekly frequency (none; 1–2 times; 3–4 times; 5–7 times; ≥8 times), and the proportion of vigorous PA to total volume of PA (none; 0%; 1%–33%; 34%–66%; 67%–100%) with odds of hypertension and obesity from 2000 to 2021. The cumulative incidence of hypertension was 6% in the 1973–1978 and 23% in the 1946–1951 cohort; 27% of women in the 1973–1978; and 15% in the 1946–1951 cohort developed obesity over the period. Overall, a higher volume of PA was associated with reduced odds of hypertension and obesity. When the volume of PA was considered, the odds of hypertension did not vary according to the frequency or intensity of PA. However, increased proportion of vigorous PA to the total volume of PA was associated with a small additional reduction in the risk of obesity. PA volume appears to be more important than the pattern of accumulation for the prevention of hypertension and obesity. Incorporating more sessions, particularly of vigorous-intensity PA, may provide extra benefits for the prevention of obesity. [Display omitted] [ABSTRACT FROM AUTHOR]

It is not clear whether the amount and frequency of psychotherapy is associated with treatment effects for adult depression. We investigated whether a number of indicators of the amount and frequency of psychotherapy were related to the treatment effects in randomized controlled trials (RCTs) comparing individual, face-to-face psychotherapy to a control group (e.g., care-as-usual [CAU] or waitlist condition [WL]). Four databases were systematically searched, and meta-regression analyses conducted to assess the relationship between the effect size (Hedges' g) of the treatment and number of sessions, duration of psychotherapy, total contact time with the therapist, and number of sessions per week. We included 176 studies (210 comparisons) with 15,158 participants. We did not find a relationship between the effect size, and number of sessions, or total contact time. There was a small negative association between duration of treatment and the effect size, an additional week of treatment was related to a 0.014 decrease in the effect size. In addition, there was a strong association between number of sessions per week and the effect size, an increase from one to two sessions per week was related to an effect size higher by 0.596. Both associations were no longer significant when controlling for characteristics of studies. The current findings are correlational, future research should thus address this question in an RCT. We should deliver brief therapies, and thus shorten waiting lists. More sessions, if necessary, should be delivered with higher frequency and over a shorter period of time. • Number of sessions is not associated with treatment effects in adult depression. • Contact time between therapists and clients is not related to treatment effects. • An extra week of treatment is related to a small decrease in treatment effects. • Delivering 2 instead of 1 treatment session per week increases treatment effects. • Associations are not significant when characteristics of studies are considered. [ABSTRACT FROM AUTHOR]

In this paper, the effects of frequency on the flash sintering behavior and microstructure of Li 6.4 Ga 0.2 La 3 Zr 2 O 12 (0.2Ga-LLZO) were investigated. The results showed that an increase in frequency had little effect on the onset temperature, but this increase reduced the duration of the weak current stage the incubation stage. Moreover, this phenomenon led to a decrease in the power loss during the constant current stage. Scanning Electron Microscope images showed that the microstructure was symmetrically distributed, and the uniformity increased with increasing frequency. Finite element simulations and an IR thermocamera were used to analyze the temperatures of the specimens. The symmetric distribution of temperature during the flash sintering process was the root cause. The results of AC impedance spectroscopy showed that when the frequency of flash sintering was ≥ 400 Hz, the ionic conductivity of Ga-LLZO was greater than that of conventional sintering. The results of this work demonstrated the important role of frequency in controlling the microstructures of ceramic materials in flash sintering. [ABSTRACT FROM AUTHOR]

• Reconfigurable graphene antenna. • Cognitive radio network. • Innovative solution for X-band satellite communications. • Improvement in satellite communication performance. This study introduces a graphene-based antenna tailored for X-band satellite communication within a cognitive radio network. Leveraging graphene's distinctive traits high conductivity and mechanical flexibility, the antenna design achieves reconfigurability in frequency, polarization, and radiation pattern. This adaptability enables dynamic adjustments to environmental shifts, bolstering the efficiency and dependability of satellite communication. Operating on software-defined radio technology, the cognitive radio system monitors and allocates the available frequency spectrum, allowing real-time adjustments to antenna parameters. Given the widespread usage of the X-band in satellite communications, this antenna proposal stands as an appealing solution for such systems. Its potential applications encompass providing broadband access in remote regions, supporting emergency communication networks, facilitating maritime and aeronautical communications, and enabling self-sustaining wireless networks. The approach involves a novel graphene antenna with slots to facilitate frequency reconfigurability. At 9 GHz, the graphene antenna achieves a gain of 6 dBi, surpassing the 4.3 dBi gain of a copper antenna. By varying the chemical potential of graphene from 0 to 4 eV , we achieved a high gain of 6.4 dBi at 9 GHz and an excellent reflection coefficient of −42 dB at 11.63 GHz. The graphene antenna's improved gain and tuning capabilities surpass traditional materials, showcasing adaptability across diverse frequencies, promising versatility for varied communication needs, and enhancing overall system reliability and effectiveness. [ABSTRACT FROM AUTHOR]

Two phase flows are common in pipeline engineering, and most times, the assumption of single phase flow is usually assumed. In this paper, the dynamics of a slightly curved Maxwell viscoelastic pipe conveying two phase flow under four boundary conditions; cantilever, simple supported, clamped simply supported and clamped clamped supported is investigated. Eigenfunction expansion was used to discretize the PDE into four modes. The linear analysis results show that the Maxwell viscoelastic parameter has no significant effect on the first and the second modes of the vibration, but on the third and fourth modes for the three boundaries conditions considered. The void fraction has effects on the frequency and critical velocity only if the densities of the components of the two phase fluid are significantly large. The nonlinear dynamics shows that Maxwell viscoelastic parameter reduces the bifurcation position and changes the bifurcation point from being sharp to a gentle curve at the bifurcation point. Further results were presented for the Maxwell parameter and velocity of fluid and temperature loading on the pipe, which are very important to understanding the behavior of Maxwell viscoelastic pipe conveying two phase flow. • Vibrations of a slightly curved Maxwell viscoelastic pipe conveying two phase flow are investigated. • The governing equation for the pipe is derived based on Hamilton's principle. • The two-phase components densities determine whether the flow can be classified as single phase or two phase. • Maxwell parameter tends to affect the response of the nonlinear system significantly when the value ranges from zero to 50. [ABSTRACT FROM AUTHOR]

To make recommendations on managing the surveillance of patients with stage I, II, III or resectable IV melanoma who are clinically free of disease following treatment with curative intent. This guideline was developed by Ontario Health's (Cancer Care Ontario's) Program in Evidence-Based Care and the Melanoma Disease Site Group (including seven medical oncologists, four surgical oncologists, three dermatologists, one radiation oncologist and one patient representative). The MEDLINE, EMBASE, Cochrane Library, PROSPERO databases and the main relevant guideline websites were searched. Internal and external reviews were conducted, with final approval by the Program in Evidence-Based Care and the Melanoma Disease Site Group. The Grading of Recommendations, Assessment, Development and Evaluation approach was followed, and the Modified Delphi method was used. Based on the current evidence (eight eligible original study papers and four relevant guidelines) and the clinical opinions of the authors of this guideline, the initial recommendations were made. To reach 75% agreement for each recommendation, the Melanoma Disease Site Group (16 members) voted twice and one recommendation was voted on three times. After a comprehensive internal and external review process (including national and international reviewers), 12 recommendations, three weak recommendations and six qualified statements were ultimately made. After a systematic review, a comprehensive internal and external review process and a consensus process, the current guideline has been created. The guideline authors believe that this guideline will help clinicians, patients and policymakers make well-informed healthcare decisions that will guide them in clinical melanoma surveillance and ultimately assist in improving patient outcomes. [ABSTRACT FROM AUTHOR]

• The high frequencies of CFTR variants can be explained by a selective advantage for healthy carriers (4–6 % per generation). • Spreading of disease-causing allele carriers was accelerated towards the end of the 18th century. • The most widespread variant (F508del) is estimated to have appeared approximately 190 generations ago. The French region of Brittany presents one of the highest cystic fibrosis (CF)-causing allele frequency in Europe. Here, we tested two hypotheses: i) CF-causing allele carriers arrived by sea in the middle of the 1st millennium AD, and ii) a selective advantage for healthy carriers explains this high rate. From the census of cystic fibrosis patients, frequency maps of the most widespread alleles were established. A mathematical model was developed, based on birth date and place of the ancestors of these patients over 5 centuries, to determine the distribution of local migrations and their parameters for inter-generational intervals of 32 years. This model was applied to simulate the spread of CF-causing variant carriers, according to different scenarios that corresponded to the immigration of a given number of variant carriers at different times (year) and places, and to compare their results to current frequency maps. Migrants carrying a CFTR variant settled in several locations, around which they spread, notably in Central Brittany (F508del variant), Léon (G551D variant) and Cornouaille (1078delT variant). Until the end of the 18th century, the spreading of disease-causing allele carriers was relatively slow, and allele frequencies progressively increased. Then, the mean migration distances increased rapidly, leading to a decline in local frequencies. The main CFTR variants could only have reached their current frequencies through a selective advantage for healthy carriers of the order of 4–6 % at each generation. For the most widespread variant (F508del), the model supports the hypothesis that it appeared around 190 generations ago. [ABSTRACT FROM AUTHOR]

The Paris-Lyon line is the busiest High-Speed Line in Europe and has been open to competition in open access since December 18, 2021. The main objective of the paper is to explore the effects for users with respect to price and frequency compare with the existing literature. The analysis is based on a large database (n = 1243) collected by web scraping from September 2019 to October 2022. The method relies on a descriptive analysis with a similar route without competition (Paris-Bordeaux) in the comparison group. The results highlight an increase of frequency by 15% and a decrease in price by 23%. The prices charged by the newcomer are lower than those of the incumbent (−30% to −50%). The comparison with the control route suggests a positive effect on price that moderates the economic catch-up effect following the COVID-19 pandemic in an inflationary context. More specifically, SNCF appears to take a wait and see attitude to competitive pressure from Trenitalia. It has moderated its prices since the new offer was introduced and has maintained its trains. • Competition have a positive effect on user welfare. • Barriers to competition underscore the importance of public regulation for success. • Incumbent adopts a wait and see attitude in response to competitive pressure. [ABSTRACT FROM AUTHOR]

The development of electricity generation from renewable sources, particularly photovoltaic energy (PV), as well as the significant growth of electric mobility with electric vehicles (EVs), leads us to contemplate the potential impacts of these components may have on an existing distribution electrical network. An electrical distribution network is designed to supply electrical loads in one specific direction while maintaining the quality of its technical parameters, such as current, voltage, and frequency. In this article, through a literature review, we will explore how the integration of each component, photovoltaic energy, and electric vehicles, individually and in combination, can impact the electrical distribution network. In addition, we will examine based on a literature review, the methods proposed by various authors to enhance the impacts occurring on the network due to this integration. [ABSTRACT FROM AUTHOR]

Deep neural networks have achieved outstanding performance in computer vision tasks. Convolutional Neural Networks (CNNs) typically operate in the spatial domain with raw images, but in practice, images are usually stored and transmitted in their compressed representation where JPEG is one of the most widely used encoder. Also, these networks are computationally intensive and slow. This paper proposes performing the learning and inference processes in the compressed domain in order to reduce the computational complexity and improve the speed of popular CNNs. For this purpose, a novel graph-based frequency channel selection method is proposed to identify and select the most important frequency channels. The computational complexity is reduced by retaining the important frequency components and discarding the insignificant ones as well as eliminating the unnecessary layers of the network. Experimental results show that the modified ResNet-50 operating in the compressed domain is up to 70% faster than the spatial-based traditional ResNet-50 while resulting in similar classification accuracy. Moreover, this paper proposes a preprocessing step with partial encoding to improve the resilience to distortions caused by low-quality encoded images. Finally, we show that training a network with highly compressed data can achieve a good classification accuracy with up to 93% reduction in the storage requirements of the training data. [ABSTRACT FROM AUTHOR]

A comprehensive assessment of catatonic symptoms is decisive for diagnosis, neuronal correlates, and evaluation of treatment response and prognosis of catatonia. Studies conducted so far used different cut-off criteria and clinical rating scales to assess catatonia. Therefore, the main aim of this study was to examine the frequency and distribution of diagnostic criteria and clinical rating scales for assessing catatonia that were used in scientific studies so far. We conducted a systematic review using PubMed searching for articles using catatonia rating scales/criteria published from January 1st 1952 (introduction of catatonic schizophrenia to first edition of the Diagnostic and Statistical Manual of Mental Disorders [DSM]) up to December 5th, 2022. 1928 articles were considered for analysis. 1762 (91,39 %) studies used one and 166 (8,61 %) used ≥2 definitions of catatonia. However, 979 (50,7 %) articles did not report any systematic assessment of catatonia. As for clinical criteria, DSM criteria were used by the majority of studies (n = 290; 14.0 %), followed by International Classification of Diseases (ICD) criteria (n = 61; 2.9 %). The Bush-Francis Catatonia Rating Scale (BFCRS) was found to be by far the most frequently utilized scale (n = 464; 22.4 % in the respective years), followed by Northoff Catatonia Rating Scale (NCRS) (n = 31; 1.5 % in the respective years). DSM and ICD criteria as well as BFCRS and NCRS were most frequently utilized and can therefore be recommended as valid instruments for the assessment of catatonia symptomatology. [ABSTRACT FROM AUTHOR]

The effect of cathodic polarization on plasma electrolytic oxidation (PEO) of the refractory metal of tantalum is investigated in 10 g/l NaAlO 2 +2 g/l KOH under 1000 and 100 Hz. Ceramic coatings are formed under various cathodic-to-anodic current densities ratios (R = jc/ja) of 0, 0.6, 1.3 and 2.3. For PEO under 1000 Hz, the plasma discharges intensify with the increase of R from 0 to 1.3, with optical emission from Ta being detected at later stage of PEO under cathodic polarization. However, excessive R ratio of 2.3 has caused early extinguishment of the plasma discharges. Correspondingly, thicker coatings are formed as the R ratio increases from 0 to 1.3, and the coating under R = 1.3 exhibits a most porous outer layer. A thin and compact coating is formed under R = 2.3. It is also found that the application of cathodic polarization increases the Na content in the resultant coatings, with a new crystalline phase NaTaO 3 being formed under R = 2.3. Cathodic polarization also decreases the corrosion resistance of the coatings. Surface wettability tests show that the coatings formed under R = 1.3 are the most hydrophilic. PEO under 100 Hz shows some differences in discharge and coating formation. Larger sized discharges are also observed at the later stage under R = 0.6, but Ta species are detected at a delayed time. For the R values of 1.3 and 2.3, patches of soft sparking occur on the sample surface, leading to non-uniform coatings. This study shows that both cathodic polarization and frequency significantly affect the PEO process. Moreover, compared with the PEO of Al, tantalum responds quite differently to cathodic polarization. Mechanisms of coating formation have been illustrated: Protons and other cations are attracted by cathodic electric field into the coatings, where they undergo a series of reactions to significantly affect the PEO behaviors. [ABSTRACT FROM AUTHOR]

The accurate measurement of physiological pressures is vital in both anaesthesia and intensive care. To obtain the greatest accuracy, invasive and semi-invasive pressure monitors can be used to measure different fluid and compartment pressures (arterial, venous, intracranial, abdominal, etc.). This article will focus primarily on the measurement of arterial blood pressure. Pressure is a measure of force applied over an area; pulsatile pressure can be measured using waveform analysis. Accurate measurement of this requires a transducer to convert a pressure wave into a form of energy that can be accurately displayed. A pressure waveform seen in an arterial line trace is composed of multiple sine waves 'layered' on top of one another (The fundamental or 'biggest' wave and multiple harmonics). Blood pressure can be affected by pressure wave frequencies interacting with the measuring system causing amplification (resonance). Equally the measuring system can absorb energy leading to a reduction (damping) of the size of the measured pressure wave. These two effects lead to inaccuracy in blood pressure measurement, but can be compensated for. [ABSTRACT FROM AUTHOR]

This Systematic Review (SR) was to report on the prevalence of pulp stones in the Saudi Arabian (KSA) population. The electronic databases were searched for scientific research articles during May 2021. The data search was performed in electronic search engines like PubMed, Scopus, Web of science, and Saudi Digital Library, and 6 original research articles which fulfilled the eligibility criteria were assessed for qualitative data. The prevalence of pulp stones among the KSA population ranged from 4.6% to 50.93% among the study participants and it ranged between 10.2%−13.34% in the teeth assessed. The pulp stones were more frequently reported in decayed teeth, periodontal diseases, attrition, teeth with dental restorations, and higher in the molar teeth in comparison with the premolar teeth. The data on the prevalence of pulp stones among the Saudi population will be helpful for clinicians in planning endodontic procedures. [ABSTRACT FROM AUTHOR]

Acute physiological and biomechanical alterations have been reported following whole-body vibration (WBV). Stiffening of muscles has only been anecdotally reported in response to WBV. Accordingly, this study investigated active plantar flexor muscle stiffness in response to a single WBV bout at four mechanical vibration frequencies. Thirteen healthy adults (37.1 ± 14.4 years old) randomly received WBV in 4 different frequencies (6, 12, 24, and 0 Hz control) for 5 min. Shear wave speed (SWS) in longitudinal and transverse projections, architecture, and electric muscle activity were recorded in the medial gastrocnemius (MG) and soleus (SOL) muscle during graded plantar flexor contraction. Subjective rating of perceived muscle stiffness was assessed via Likert-scale. SWS of the MG at rest was enhanced in response to 5 min of 24 Hz WBV (p = 0.025), while a small reduction in SOL SWS was found during contraction (p = 0.005) in the longitudinal view. Subjective stiffness rating was increased following 12 Hz intervention. After 24 Hz WBV, pennation angle for MG was decreased (p = 0.011) during contraction. As a secondary finding, plantar flexor strength was significantly increased with each visit, which, however, did not affect the study's main outcome because of balanced sequence allocation. SWS effects were solely limited to 24 Hz mechanical vibration and in the longitudinal projection. The observed effects are compatible with an interpretation by post-activation potentiation, warm-up, and force-distribution within the triceps surae muscles following 5 min WBV. The outcome may suggest SWS as a useful tool for assessing acute changes in muscle stiffness. [ABSTRACT FROM AUTHOR]

This paper deals with the established research trend that seeks to enhance wind turbine generator involvement levels in fast regulation of the grid frequency (inertia emulation) along with traditional power system Alternators. At the beginning, the scattered control objectives in previous studies for wind energy conversion system are gathered in a unified scheme where it portrays an augmented control horizon that assorts different control objectives into levels and layers along with its interconnection. In accordance with that, the recently imposed constraints by the system operator in some countries for shaping the necessary behavior of such wind turbine systems to ensure efficient and reliable power supply is briefly discussed in two operational conditions: normal and abnormal (fault) conditions. The paper then identified four control approaches to supply an inertial response emulation in order to alleviate frequency excursion especially for the first 10 s time frame. These control techniques are namely "Natural Inertia Control," "Stepwise Inertial Control", "Virtual Synchronous Machine Control," and "De-loading Control". Several forms for each control approach are introduced and discussed in terms of the main principle, general advantages, and disadvantages. Finally, for each control technique and its variants, comprehensive comparisons between the surveyed controllers are presented. [ABSTRACT FROM AUTHOR]

Among many risk assessment techniques, qualitative, semi-quantitative or quantitative, risk matrix is a common tool to assess risk by allocating frequency and consequence of an accident to one of the pre divided frequency and consequence categories. However, since there is no standardized way to define these categories, risk matrix with its strength of being straightforward to use and easy to interpret has inherent uncertainties including objective categorization determination and consistency of decisions on frequency and consequence among different users, which usually results in multiple risk outcomes leading to incorrect conclusion about decision making on risk initiated from accidents. The purpose of the study is to predict a long term risk of maritime accident using a 5 × 5 probabilistic risk matrix where each category of frequency and consequence is probabilistically estimated by a Markov chain model. The proposed method to calculate accident risk is illustrated using maritime accident data over 2016–2020 years. The findings are that the most probable frequency and consequence ranges of maritime accidents will be between 182 and 235 with probability of 0.3878 and between 6.8 and 11.6 fatalities with probability of 0.3791, respectively. The expected risk value was computed as 4.6506 on a scale of 2–10. For the validation of the proposed method 90 %, 95 %, and 99 % confidence intervals were constructed which were shown to contain the predicted risk value. The probabilistic risk matrix with Markov chain approach can be applied to predicting risks in different fields of industries. [ABSTRACT FROM AUTHOR]

• Neurostimulation based on axon orientation, cell body proximity, and axon thickness can target therapeutic axonal pathways. • High frequency stimulation and low frequency sinusoidal waveforms may help to refine spatial targeting in Deep Brain Stimulation. • Visualizing lead placement in relation to white matter tracts using diffusion-tractography can guide waveform parameter settings. Neurostimulation has diverse clinical applications and potential as a treatment for medically refractory movement disorders, epilepsy, and other neurological disorders. However, the parameters used to program electrodes—polarity, pulse width, amplitude, and frequency—and how they are adjusted have remained largely untouched since the 1970 s. This review summarizes the state-of-the-art in Deep Brain Stimulation (DBS) and highlights the need for further research to uncover the physiological mechanisms of neurostimulation. We focus on studies that reveal the potential for clinicians to use waveform parameters to selectively stimulate neural tissue for therapeutic benefit, while avoiding activating tissue associated with adverse effects. DBS uses cathodic monophasic rectangular pulses with passive recharging in clinical practice to treat neurological conditions such as Parkinson's Disease. However, research has shown that stimulation efficiency can be improved, and side effects reduced, through modulating parameters and adding novel waveform properties. These developments can prolong implantable pulse generator lifespan, reducing costs and surgery-associated risks. Waveform parameters can stimulate neurons based on axon orientation and intrinsic structural properties, providing clinicians with more precise targeting of neural pathways. These findings could expand the spectrum of diseases treatable with neuromodulation and improve patient outcomes. [ABSTRACT FROM AUTHOR]

The paper examines to what extent expressing information sources with a fully grammaticalized evidential system or with lexical means may have a different pragmatic impact in conversation. A contrastive corpus of Tibetan (TSC) and English (CSC/LAC) allows me to investigate several dimensions: frequency, semantic schematicity, optionality, economy, and information hierarchy. The data from the contrastive corpus indicate that Tibetan evidentials are on average 6.7 times more frequent than English evidentials. Tibetan evidentials are also functionally more schematic, since English evidentials usually contain more semantic features. This compels English speakers to be more specific when referring to their information sources. Grammatical evidential systems may be less optional than lexical systems, but the degree of optionality differs depending on the linguistic level. The morpho-syntactic obligatoriness of many Tibetan evidentials may indeed be compensated by the availability of evidentially neutral forms in the same paradigm. However, evidentiality seems to be pragmatically less optional in Tibetan than in English. Tibetan evidentials are also more economical on a morpho-phonetic, syntactic, and cognitive level. Finally, all these parameters influence the informational status of evidentials. Because they are more frequent, schematic, obligatory, and economical, Tibetan evidentials appear more backgrounded. • Tibetan evidentials are on average 6.7 times more frequent than English evidentials. • Tibetan evidentials are semantically more schematic than English evidentials. • Tibetan evidentials are pragmatically more optional than English evidentials. • Tibetan evidentials are more economical than English evidentials. • Tibetan evidentials tend to be more backgrounded than English evidentials. [ABSTRACT FROM AUTHOR]

Functional connectome studies have revealed widespread connectivity alterations in major depressive disorder (MDD). However, the low frequency bandpass filtering (0.01–0.08 Hz or 0.01–0.1 Hz) in most studies have impeded our understanding on whether and how these alterations are affected by frequency of interest. Here, we performed frequency-resolved (0.01–0.06 Hz, 0.06–0.16 Hz and 0.16–0.24 Hz) connectome analyses using a large-sample resting-state functional MRI dataset of 1002 MDD patients and 924 healthy controls from seven independent centers. We reported significant frequency-dependent connectome alterations in MDD in left inferior parietal, inferior temporal, precentral, and fusiform cortices and bilateral precuneus. These frequency-dependent connectome alterations are mainly derived by abnormalities of medium- and long-distance connections and are brain network-dependent. Moreover, the connectome alteration of left precuneus in high frequency band (0.16–0.24 Hz) is significantly associated with illness duration. Multisite harmonization model only removed linear site effects. Neurobiological underpinning of alterations in higher frequency (0.16–0.24 Hz) should be further examined by combining fMRI data with respiration, heartbeat and blood flow recordings in future studies. These results highlight the frequency-dependency of connectome alterations in MDD and the benefit of examining connectome alteration in MDD under a wider frequency band. • FCS in the low frequency band (0.01-0.06 Hz) is highly reproducible, and is more sensitive to MDD alterations. • Frequency-resolved FCS alterations of MDD consisted by altered medium-/long-distance, inter-network functional connections. • FCS alterations of MDD in higher frequency are associated with illness duration. [ABSTRACT FROM AUTHOR]

Boron nitride nanosheets (BNNS) were mixed with rutile TiO 2 and (Al, Nb)-codoped ceramics (ANTO) powders by heteroaggregation method. Homogeneous ceramics with the single phase of rutile TiO 2 were obtained by subsequent solid-state sintering. Scanning transmission electron microscope (STEM) and X-ray photoelectron spectrometer (XPS) results show that N was doped into the crystal lattice during sintering. It is shown that the strong electron localization of the covalent N i –O bond formed between interstitial N (N i) and adjacent O atom shifts the cutoff frequency of high permittivity from ∼100 kHz to 100 MHz in both rutile TiO 2 and the ANTO systems. Particularly, the ANTO-0.6BNNS sample exhibits optimum dielectric properties with a permittivity of 1.3 × 104 and tan δ of 0.04 measured at 1 MHz. Meanwhile, the colossal permittivity of ANTO-0.6BNNS with tan δ < 0.1 shows good temperature stability in the temperature range of 200–400 K. [ABSTRACT FROM AUTHOR]

Soaring complexity in supply chains with more fluctuations and ever increasing uncertainty in demand puts an increased focus on flexibility and changeability in manufacturing. Thus, it is increasingly important to determine the right change type, such as changes in the number of employees or overtime, at the right time in order to be able to react appropriately and sustainably to changes in demand. The developed approach uses frequency analysis to predict future changes in demand in different frequency ranges in order to assign appropriate change types to them and optimize the change intensity for each change type and time step. The foundation of the related algorithm is a discrete Fourier analysis that extracts relevant frequencies and assigns change types using generative algorithms to enable cost-minimizing production. The algorithm is validated against LSTM and ARIMA forecasting in a use case with seasonal time series including different noise levels. [ABSTRACT FROM AUTHOR]

Für komplexe osteopathische Begriffe, wie Potency, Tide, Fulkrum, primär respiratorischer Mechanismus (PRM) und auch energetische Aspekte lassen sich heute naturwissenschaftlich Entsprechungen finden, die einen geeigneten kommunikativen Austausch mit anderen naturwissenschaftlichen Bereichen ermöglichen. Besonders der Teilnehmer*innenaspekt, den schon Rollin Becker als Beteiligtsein der osteopathischen Behandler*innen in der palpatorischen Beziehung mit Patient*innen aufbrachte, kann dadurch beleuchtet werden. Scientific equivalents can now be found for complex osteopathic terms such as potency, tide, fulcrum, primary respiratory mechanism (PRM) and also energetic aspects, which enable a communicative exchange with other scientific areas. In particular, the participant aspect, which Rollin Becker already brought up as the participation of the osteopathic practitioners in the palpatory relationship with patients, can be illuminated in this way. [ABSTRACT FROM AUTHOR]

Nonsuicidal self-injury (NSSI) has been repeatedly associated with increased suicide risk. However, the transition from NSSI to suicidal thoughts and behaviors still remains as an enigma. One possible construct that may influence this relationship is cognitive flexibility, which refers to the ability to adapt responses/strategies based on environmental feedback. It may be that greater cognitive flexibility increases one's cognitive accessibility to suicide, making it a more viable option upon distress especially for those with a prior history of NSSI. Conversely, it may be that less cognitive flexibility creates a negative bias that exacerbates the effects of NSSI on suicide. Thus, in this study, we examined how NSSI characteristics (i.e., frequency and methods) interact with cognitive flexibility to predict lifetime suicide attempt (SA) history. Participants were 505 individuals with a lifetime history of NSSI who completed a survey assessing for their NSSI experiences, cognitive flexibility, and SA history. Moderation analyses were conducted while controlling for sexual orientation, which significantly predicted SA history. Results indicated a significant interaction between number of NSSI methods endorsed and cognitive flexibility. In particular, individuals were more likely to have had a history of SA if they scored higher on the alternative subscale of cognitive flexibility. The results suggest that the adaptive value of cognitive flexibility may be context dependent, and highlight the importance of personalized care among those who engage in self-harm. [ABSTRACT FROM AUTHOR]

• A thermally-coupled three-stage SPTC reaching a no-load temperature of 3.96 K with He-4 is developed. • The influence of frequencies on the regenerator and the cold inertance tube are analyzed. • Optimization of frequencies under different cooling and precooling temperatures is studied. • The maximum cooling capacity of 69 mW @6 K or 113.4 mW @7 K are obtained. Long-life cryocoolers operating below 7 K are crucial for infrared astronomy projects, such as the hybrid cryocooler employed as the MIRI cryogenic system in the James Webb Space Telescope, which provides a cooling temperature of 6.2 K. A totally thermally-coupled three-stage Stirling-type pulse tube cryocooler was developed in SITP to obtain a relatively high cooling capacity at 6∼7 K. With the cold inertance tube as the phase shifter of the third stage pulse tube cryocooler, a no-load temperature of 3.96 K was reached with He-4. The operating frequency was 26.5 Hz, and the average pressure was 1.68 MPa at room temperature. Simulation results show that the frequency of the third stage SPTC has significant effects on the impedance characteristics of the cold inertance tube and the efficiency of the low-temperature regenerator. The effect of frequency on the cooling capacity has been verified experimentally, and the optimal frequency changes with cooling temperatures and precooling temperatures. When the precooling temperatures of the first stage and the second stage were 90 K and 24 K, the cooling capacity of 58.5 mW@6 K and 113.4 mW@7 K under 100 W input electric power of the third stage SPTC were obtained with the optimized operating frequencies of 24.5 and 23 Hz, respectively. The total input electric power was 510 W when achiveing 113.4 mW@7 K. [ABSTRACT FROM AUTHOR]

This study evaluated student reported achievement of essential elements (EE) across three required advanced pharmacy practice experiences (APPEs) to identify differences in the frequency of each EE during different delivery modalities. APPE students from three different programs were assigned a self-assessment EE inventory after required acute care, ambulatory care, and community pharmacy APPEs between May 2018 and December 2020. Using a four-point frequency scale, students reported exposure to and completion of each EE. Pooled data were analyzed to compare differences in frequencies of EE during standard and disrupted delivery. All standard delivery APPEs were in-person, but during the study period APPEs shifted to a disrupted delivery using hybrid and remote formats. Frequency changes were reported as combined data and compared between programs. A total of 2191 of 2259 (97%) evaluations were completed. Acute care APPEs had a statistically significant change in frequency of evidence-based medicine elements. Ambulatory care APPEs had a statistically significant decrease in the frequency of reported pharmacist patient care elements. Community pharmacy had a statistically significant decrease in frequency in each category of EE except practice management. Statistically significant differences between programs were observed for select EEs. The frequency of EE completion during disrupted APPEs revealed minimal change. Acute care was the least impacted whereas community APPEs experienced the greatest change. This may be attributable to shifts in direct patient interactions during the disruption. Ambulatory care was impacted to a lesser degree, potentially due to utilization of telehealth communications. [ABSTRACT FROM AUTHOR]

To investigate the frequency of fibromyalgia syndrome (FMS) among medical students and its stratifications. The work included 513 medical students from Kafrelsheikh University. The 2010 and 2016 American College of Rheumatology (ACR) fibromyalgia classification criteria were used to determine the presence of FMS. The chronic pain grade questionnaire was used to assess pain severity and impact on daily activities, recreational, social and family activities, and ability to work. The students were 296 females (57.7 %) and 217 males (42.3 %). 64 (12.5 %) fulfilled the 2010 criteria (F:M 2.8:1) (p = 0.015). The frequency of female affection was 15.9 % (47/296) compared to 7.83 % (17/217) in male. 37 (7.2 %) fulfilled 2016 criteria and only six cases (9.3 %) were known to have FMS. The frequency of FMS in students of the first 3 years (basic science) and the following 3 years (clinical) was 14.1 % and 9.5 %, respectively. Considering the chronic pain grade, there was a significant difference (p < 0.0001) in all pain items, daily recreational, social, family activities, and ability to work between those with and without FMS. 213 (41.5 %) had knowledge about FMS and the source of their information was from social media (39.4 %), their academic study (26.8 %), web pages (25.4 %) and friends (8.5 %). Fibromyalgia is highly frequent among medical students, especially females of basic years with a high impact on recreational, social, family activities, and ability to work. Medical students should be considered a "high-risk" group for FMS and should be educated about it and managed accordingly. [ABSTRACT FROM AUTHOR]

Meeting carbon-reduction targets will require thorough consideration of climate variability and climate change due to the increasing share of climate-sensitive renewable energy sources (RES). One of the main concerns arises from situations of low renewable production and high demand, which can hinder the power system. We analysed energy droughts, defined as periods of low energy production (wind plus solar generation) or high residual load (demand minus production), in terms of two main properties: duration and severity. We estimated the joint return periods associated with energy droughts of residual load and power production. We showed that moderate winter energy droughts of both low renewable production and high residual load occur every half a year, while summer events occur every 3.6 and 2.4 years (on average). As expected, the occurrence of energy droughts tends to decrease with the degree of the severity of the energy drought, and moderate and extreme energy droughts showed longer return periods for most countries. In general, we found a large variability across Europe in summer, with some countries (e.g. Italy) being more sensitive to energy droughts. Our results highlight the relevance of sharing RES during prolonged periods of low production and high demand. • European countries are frequently exposed to moderate winter energy droughts. • Copulas model the dependence between the duration and the severity of energy droughts. • Energy droughts are more frequent and longer lasting in winter than in summer. • Joint return periods increase with the degree of the severity of the energy droughts. [ABSTRACT FROM AUTHOR]

Convert Image Communication (CIC) is a promising technology to protect the privacy of images. Recently, the emergence of robust CIC resistant to JPEG compression has gained due to the widespread use of JPEG compression in image communication. This paper introduces a R ̲ obust image hiding network with F ̲ requency and S ̲ patial A ̲ ttentions (RFSA) to implement robust CIC. RFSA can hide an image within another image with high robust. It incorporates multiple image attentions corresponding to imperceptibility, recovered image quality, and resistance to JPEG compression, which ensure that secret images are hidden within regions that cause little distortion and can well withstand JPEG compression. Additionally, two encoders, that is, a frequency encoder and a spatial encoder, are mixed to adaptively embed secret images across both frequency and spatial domains. Experimental results demonstrate that the proposed scheme not only maintains high image quality and capacity but also exhibits exceptional resistance to JPEG compression compared to other state-of-the-art image hiding methods. The average Peak Signal-to-Noise Ratio (PSNR) of the recovered image remains at 24.96 dB even under JPEG compression with a quality factor of 55. • We use frequency domain to capture the intrinsic DCT changing in JPEG compression. • Multi-attentions are derived based on compression affect and the human visual system. • Experiments show high image quality and resilience to JPEG compression of our scheme. [ABSTRACT FROM AUTHOR]

In this study, the variations in hydrogen content and oxide content in alloys under 0 W, 500 W, 1000 W, 1500 W, 2000 W, 2500 W, 3000 W, and at 20 kHz, 30 kHz, 40 kHz were investigated. Hydrogen content was assessed using porosity and computed tomography, while oxygen content in the alloy was measured using element analyzer and elemental scanning. Compared to other conditions, the melt had the lowest hydrogen and oxide contents at a frequency of 20 kHz and an ultrasonic power of 2500 W, with values of 0.099 cm3/100 g and 0.0015 %, respectively. Experimental observations also indicate that the variations in hydrogen content and oxide content in the alloy during ultrasonic treatment are almost similar. In most cases, lower hydrogen content corresponds to lower oxide content in the same alloy. This is because hydrogen bubbles and oxides become a single entity. At the same time, ultrasonic purification increases the tensile strength of the alloy to 200.1 MPa and the elongation rate to 0.72 %. This study primarily investigates the relationship between hydrogen bubbles and oxides in aluminum melt under different ultrasonic frequencies and power levels, providing significant reference for the purification of various fluids under ultrasonic fields. [ABSTRACT FROM AUTHOR]

To evaluate the frequency of antimicrobial-resistant bloodstream infections (AMR BSI) in Thailand. We analyzed data from 2022, generated by 111 public hospitals in health regions 1 to 12, using the AutoMated tool for Antimicrobial resistance Surveillance System (AMASS), and submitted to the Ministry of Public Health, Thailand. Multilevel Poisson regression models were used. The most common cause of community-origin AMR BSI was third-generation cephalosporin-resistant Escherichia coli (3GCREC, 65.6%; 5101/7773 patients) and of hospital-origin AMR BSI was carbapenem-resistant Acinetobacter baumannii (CRAB, 51.2%, 4968/9747 patients). The percentage of patients tested for BSI was negatively associated with the frequency of community-origin 3GCREC BSI and hospital-origin CRAB BSI (per 100,000 tested patients). Hospitals in health regions 4 (lower central region) had the highest frequency of community-origin 3GCREC BSI (adjusted incidence rate ratio, 2.06; 95% confidence interval: 1.52–2.97). Health regions were not associated with the frequency of hospital-origin CRAB BSI, and between-hospital variation was high, even adjusting for hospital level and size. The high between-hospital variation of hospital-origin CRAB BSI suggests the importance of hospital-specific factors. Our approach and findings highlight health regions and hospitals where actions against AMR infection, including antimicrobial stewardship and infection control, should be prioritized. • The frequency of AMR BSI in 111 public hospitals in Thailand in 2022 was studied. • The frequency of community-origin 3GCREC BSI was different by regions. • The frequency of hospital-origin CRAB BSI varied greatly among hospitals. • Underuse of BC was associated with the higher frequency of AMR BSI per tested patients. • Our findings contributed to actions against AMR at local and national levels. [ABSTRACT FROM AUTHOR]

This study examines the impact of mechanical vibration on the carbonation process of steel slag, a substantial byproduct of steel production. Employing a methodical experimental design that modulates mechanical vibration frequencies, the research reveals that mechanical vibration markedly influences carbonation, with an optimal frequency of 180 Hz leading to a 27.5 % increase in compressive strength of steel slag compact and an increase in CO 2 uptake of 6.8 %. The application of vibration appears to catalyze the conversion of calcium-rich minerals into well-formed rhombohedral calcite, which emerges as the predominant carbonation product. Mechanism analysis suggests that vibration-induced particle redistribution creates new reaction surfaces, thereby accelerating the carbonation process. However, the effect is more pronounced in early stages, with diminishing returns as carbonation progresses. These pivotal findings propose an innovative strategy to augment the efficiency of carbonation and the inherent material properties of steel slag, thereby fostering a more sustainable approach to the utilization of industrial byproducts. • Mechanical vibration is introduced to enhance properties of steel slag compact. • Compressive strength increases by 27.5 % at an optimal frequency of 180 Hz. • Mechanical vibration promotes formation of well-formed rhombohedral calcite. [ABSTRACT FROM AUTHOR]

• Diesel and diesel–biodiesel blend containing aluminum oxide nanoparticles was used in this study. • Frequency domain transformation, Welch test, Kurtosis, and RMS of acceleration were used to analyze the vibrations. • The Welch test better shows the difference between fuels and their vibration. • Engine performance becomes more erratic despite increasing the engine power by adding alumina nanoparticles to the B5 fuel. Much research has been done on the performance and emissions of engines using renewable fuels. In some cases, nano additives have been added to these fuels. Although the research results are essential, these fuels should be considered from other aspects. One of these aspects is engine vibrations, which can be related to engine ignition and knocking. In this research, the vibration of an engine and its relationship with knocking and combustion using diesel and alumina nano additives with 30, 60, and 90 ppm dosages in the diesel–biodiesel blend (B5, B10) were evaluated. Experiments were carried out using precise vibration measurement equipment in a single-cylinder, four-stroke engine. The frequency domain transformation, Welch test, Kurtosis, and RMS of acceleration were used to analyze the vibrations. The advantages and disadvantages of each method were investigated on the vibrations of each fuel blend. The results showed that despite being more complicated, the Welch test better shows the difference between fuels and their vibration. By this method, it was found that diesel fuel has the lowest vibrations at frequencies below 10 kH, but it has the highest vibrations at frequencies above 10 kH. Also, with diesel and adding alumina nanoparticles to the fuels of B5, the engine performance becomes more erratic despite increasing engine power. [ABSTRACT FROM AUTHOR]

[Display omitted] • A pulse voltage used with varying duty cycles, frequencies, and voltage amplitudes. • The least energy consumption to produce H 2 was observed in the E-50-X case. • The fastest hydrogen production occurs in the DC-Z case at 2.5 V voltage. • The lifespan of PEMWE systems using pulse signals will be longer. • Using pulse voltage preserves the surfaces of the MEA and GDL. The performance of a Proton Exchange Membrane (PEM) Water Electrolyzer (PEMWE) is heavily dependent on its operational conditions. In this study, we applied pulsed voltage with varying duty cycles, frequencies, and voltage amplitudes to the cell. We examined their effects on energy consumption, hydrogen flow rate, current consumption, and the time required to produce hydrogen. The applied frequency ranged from 1 kHz to 20 kHz, the voltage amplitude varied from 1.5 V to 2.5 V, and the duty cycle was adjusted to 50 to 80 %. According to the experimental results, the lowest energy consumption was found to be 8.82525 J.mL−1 H 2 in Case E-50-X. When a DC voltage of 1.5 V was applied, the energy consumption was 13.446 J.mL−1 H 2. Pulse voltage demonstrated the potential to mitigate corrosion formation on electrode or membrane surfaces during electrolysis, contributing to energy savings and prolonging equipment life for sustainable hydrogen production. [ABSTRACT FROM AUTHOR]

• HiperFer shows an increase in fatigue strength at LCF load with lower strain rate. • HiperFer exhibits temperature dependent cyclic hardening behavior. • Hardness of HiperFer increases up to 60% due to load induced Laves phases. • Higher hardness and fatigue strength relates to pronounced Laves phase formation. Fully ferritic, high-chromium HiperFer alloy presents a promising option, providing a combination of both, high corrosion resistance and material strength above 600 °C. Although these steels show improved strength at creep and thermomechanical loading compared to conventionally used 9–12 % Cr-steels, a comprehensive understanding of their fatigue behaviour and the influence of different strain rates is required. Hence, in this study the fatigue behaviour of HiperFer-17Cr2 was analysed in stress-controlled fatigue tests performed at temperatures above 600 °C and at 0.05 Hz and 5 Hz. Moreover, a martensitic steel P91 was investigated as a reference. The results obtained for HiperFer–17Cr2 reveal an increase in fatigue strength with a decrease in frequency and an increase in stress. Additionally, an influence of the frequency on the cyclic deformation behaviour of HiperFer-17Cr2 was observed, which is characterized by cyclic hardening. This cyclic hardening correlates with an increase in hardness, which is associated with the deformation induced formation of Laves phase particles. After LCF load with lower frequency a stronger hardness increase as well as a higher amount of Laves phase particles and smaller particle-free zones at the grain boundaries were observed, contributing to the higher fatigue strength obtained at lower strain rate. [ABSTRACT FROM AUTHOR]

The main challenge in electrochemical machining (ECM) of titanium alloys is not processing efficiency, but the difficulty in achieving high-quality machined surfaces. Titanium alloys are particularly susceptible to pitting, and there are obvious dissolution differences among different phases in ECM, which greatly affect the machining accuracy and surface quality. This paper aims to eliminate the dissolution disparity between different phases and enhance the surface quality of titanium alloys through the synergistic effect of a similar normal distribution current waveform and passivation film. A new experimental phenomenon was found that the presence of a passivation film resulted in a remarkably smooth pit during the initial pitting stage, with no discernible dissolution differences among different phases. A superior surface quality can be achieved when the surface of the titanium alloy sample is composed of these smooth pits. From this perspective, the effect of frequency and passivation film on pitting process and surface quality of titanium alloys in pulse ECM was systematically investigated. In particular, at the frequency of 100 Hz, high surface quality was achieved on Ti-6.5Al-2Zr-1Mo-1 V (TA15) alloy with a surface roughness of Ra 0.69 μm while the dissolution disparity between different phases was significantly eliminated. The rate of material thickness removal was 0.09 mm/min. Successful applications on other titanium alloys, such as Ti-6Al-4 V (TC4), Ti-25 V-15Cr-0.3Si (Ti40), and Ti-5.8Al-4Sn-3.58Zr-0.7Mo-0.5 Nb-1.1Ta-0.4Si (Ti60), further validated that high-quality surfaces can be obtained with surface roughness values of Ra 0.31 μm, Ra 0.44 μm and Ra 0.92 μm respectively. [Display omitted] • The synergistic effect of current waveform and passivation film improve the surface quality of titanium alloys in ECM. • The current waveform and frequency affect the corrosion morphology and repassivation process. • High quality surfaces of titanium alloys are achieved under optimized frequencies. [ABSTRACT FROM AUTHOR]

• New device architecture unveiled, enhancing DC/AC performance. • Comprehensive noise analysis conducted, revealing key device behavior. • Investigation of traps and temperature effects for optimized performance. • Novel design demonstrates superior DC/AC characteristics, pushing device boundaries. • Detailed illustration of proposed fabrication flow. This article offers a comprehensive noise analysis of a GaAs 0.2 Sb 0.8 /GaSb heterojunction Source-All-Around Vertical Tunnel FET (SAA-VTFET), examining generation-recombination (GRN), flicker (FN), and diffusion (DN) noise. It pioneers an investigation into noise behavior under the influence of interface traps, temperature variations, and frequencies. Analysis includes both output current noise power spectral density (S id) and input voltage noise power spectral density (S vg). Furthermore, the sensitivity of noise PSD is noted to be maximum at lower V gs (gate bias voltage), suggesting that trap-assisted tunneling (TAT) and Shockley-Read-Hall (SRH) recombination dominate over band-to-band tunneling in this region. For enhanced clarity, this study also includes an analysis of the impact of traps and temperature on both AC and DC characteristics. [ABSTRACT FROM AUTHOR]

Microstrip patch antennas have gained popularity due to their compact size, flat design, cost-efficiency, and ability to accommodate various design needs. Despite their advantages, optimizing directional properties for peak performance remains challenging. This study employs the Taguchi method, a statistical technique, to regulate the directivity of microstrip patch antennas. Thirteen input control factors are adjusted, including the patch dimensions, substrate, slot, feed line, array, and operating frequency. The Taguchi method efficiently assesses multiple experimental variables, minimizing the need for extensive experiments. The study identifies the frequency and the width of the extended feed line along the Y-axis as the most critical factors influencing directivity. The Taguchi analysis results are validated through the main effect screener analysis (MESA). As a case study, microstrip patch antennas with 30 dB directivity are designed using a tuning process of the control factors based on Taguchi results and COMSOL Multiphysics software. The simulated results at 40 GHz include a reflection coefficient of −0.098612 dB, lumped port impedance of 0.37939 + 29.012i Ω, and elevation (θ) and azimuth angles (φ) measuring 0.0 degrees. These findings indicate that the radiation pattern is being assessed in the broadside direction, directly perpendicular to the antenna, resulting in a directivity of 30 dB. This study offers a structured approach and methodology for both researchers and manufacturers to craft microstrip patch antennas tailored to precise applications, thereby minimizing the need for trial-and-error techniques. The outcomes contribute significantly to enhancing the efficacy of microstrip patch antennas across various domains such as communication, radar technology, and satellite communication. [ABSTRACT FROM AUTHOR]

While it is well recognized that mass transfer is an important factor in electrochemical reactions, the influence of mass transfer, especially of the convection on the electrochemical CO 2 reduction has not been investigated. In this study, we focused on the influence of convection in a flow cell system using a boron-doped diamond electrode. The results clearly showed that convection improved the product selectivity and electrode potentials in CO 2 reduction. It suggested that convection controls CO 2 mass transfer in a flow cell system and influences the reactivity of electrochemical CO 2 reduction. [Display omitted] • Electrochemical CO 2 reduction using a boron-doped diamond electrode was performed. • Frequencies of pressure changes in electrolytes were controlled. • The higher frequency accelerated convection in the flow cell. • Accelerated convection promoted electrochemical CO 2 reduction. • Convection influenced the mass transport of CO 2 to the electrode. [ABSTRACT FROM AUTHOR]

Covid-19 has important implications for public transport operations. Increased teleworking and the perceived infection risk on public transport vehicles have drastically reduced demand in many cities. At the same time, physical distancing has effectively reduced available peak-period public transport capacity. In this paper, we use a simple model to study the effect of these changes on second-best optimal pricing and frequency provision, assuming that car use is underpriced. A numerical application reflecting the public transport situation in Brussel is provided. Results include the following. First, more telework and the increased perceived infection risk have opposite effects on the fare, so that it may be optimal not to change the fare at all. Optimal frequency is likely to decline. Second, holding the fare and frequency constant at their pre-Covid second-best optimal values, more telework reduces the public transport deficit if car use is underpriced. Third, extending the model to allow for passengers with different vulnerability towards Covid-19, allowing fare and frequency differentiation implies that vulnerable users will face higher fares only if their risk perception is sufficiently higher than that of the non-vulnerable, and car use is not too much underpriced. Occupancy rates will be lower for the vulnerable passengers. Fourth, the numerical results for Brussels show that telework and a high perceived infection risk for workers may yield a welfare optimum whereby commuters do almost not use public transport. Offering a low frequency suffices to deal with the captive demand by school children and students. Lastly, reserved capacity for the vulnerable users and stimuli for walking and biking to school may be useful policies to deal with the crowding risk. [ABSTRACT FROM AUTHOR]

Discovering visual representation in an image category is a challenging issue, because the visual representation should not only be discriminative but also frequently appears in these images. Previous studies have proposed many solutions, however, all of them separately optimized the discrimination and frequency, which consequently makes the solutions sub-optimal. We propose a method to discover the jointly discriminative and frequent visual representation to address this issue, named as JDFR. To ensure discrimination, JDFR employs a classification task with cross-entropy loss. To achieve frequency, we design a novel similarity concentration (SC) loss to concentrate on the samples with the same representation and pull them closer in the feature space, and then mine the frequent visual representations. Moreover, we utilize an attention module to locate the representative region in the image. Extensive experiments on five benchmark datasets (Place365-20, Travel, VOC2012-10, ImageNet-100, and iNaturalist-100) show that the discovered visual representations have better discrimination and frequency than ones mined by the state-of-the-art (SOTA) method with average improvements of 5.37% on accuracy and 3.06% on frequency. [ABSTRACT FROM AUTHOR]

Incidence of postharvest losses in the fresh produce value chain is a worldwide concern facing food security and sustainability. Postharvest losses can occur along the supply chain stages such as harvesting, storing, handling, packaging, transporting, and marketing. Mechanical damage caused by vibration is one of the most common quality challenges to fresh produce during transit. Mechanical damage of fresh produce can cause considerable economic losses by reducing quality and can result in severe food safety concerns. Understanding the factors affecting fresh produce damage during transportation is significant in developing strategies for reducing postharvest losses. We review transport as an essential component in the postharvest supply chain and critically discuss the adverse effect on fresh produce, mainly due to vibration. The experimental approaches applied to measure the vibration levels during transport of fresh produce are presented. Factors influencing the vibration level discussed herein include surface condition, vehicle speed, vibration duration, vibration direction, packaging unit, etc. A comprehensive discussion on the effects of packing unit type and surface of packaging material, location of the package on the vehicle, and height of the package in a stack on the vibration level is presented. Vibration during transportation is difficult to avoid; however, applying good management practices like improving the refrigeration system, utilization of appropriate packaging, and incorporating suitable cushioning materials can reduce produce damage during transit. Overall, careful selection of better solutions to this critical issue can help to reduce fresh produce susceptibility to vibration damage during road transport and thereby reduce incidence of postharvest losses of fresh commodities. • Vibration during transit can affect the fresh produce quality. • Factors affecting for vibration level during transit are reviewed. • Role of packaging on vibration level is discussed. • Use of simulation studies are reviewed. • Strategies to fresh produce damage reduction during transit are discussed. [ABSTRACT FROM AUTHOR]

Due to the extensive construction of high-speed rail lines passing through seismically active areas, the possibility of a sudden earthquake occurring during train operation is very high. Additionally, the earthquake will intensify the dynamic response of trains and bridges, causing serious bridge damage. In this work, the dynamic response behavior of the bridge structures in the coupled train-bridge system under the earthquake is investigated based on the 4-table shaking table system. Shaking table experiments are also conducted on a high-speed railroad model of simple-supported girder bridge at a scale of 1/10 with the simulated layers of China Railway Track System type II (CRTS II) ballastless track slabs. The strain responses of various components, including rails, track plates, base plates, and beams, were measured on the bridge using quasi-distributed fiber optic gratings, both with and without seismic actions. Additionally, the seismic isolation characteristics of the fasteners and the CA mortar layer were investigated. The dynamic performance of the coupled train-bridge system under earthquakes was studied in both the time and frequency domains. [Display omitted] • First shaking table test on reduced-scale train-bridge model with CRTSⅡ ballastless track plate under running trains. • Strain response along the bridge obtained via quasi-distributed fiber Bragg grating for time-frequency analysis. • Analysis reveals vibration reduction and isolation characteristics of coupler and CA mortar layer. [ABSTRACT FROM AUTHOR]

The study explored the effects of electric field strength, temperature, and frequency on the inactivation of Clostridium sporogenes PA3679 spores (a surrogate of Clostridium botulinum) within buffer. The experiments were conducted at three different field strengths (30, 40, and 50 V/cm), temperatures (110, 120, and 130 °C), and frequencies (60, 1000, and 5000 Hz). Ohmic heating resulted in significantly greater reduction of C. sporogenes compared to conventional heating. Electric field strength significantly influenced spore inactivation. It was found that lower frequencies led to quicker rates of inactivation. Given that high field strengths have dual benefits of increasing both heating and spore kill rate, the possibility exists to process foods to sterility without a hold. This is expected to result in improved product quality, reduced process times and increased efficiency. • Ohmic heating results in higher bacterial spore inactivation than conventional heating. • This study also confirms the existence of non-thermal effects of ohmic heating. • Higher field strength offered significantly higher inactivation of spores. • 60Hz and 5000 Hz offered highest and lowest inactivation of Clostridium sporogenes. [ABSTRACT FROM AUTHOR]

• New theoretical framework for computing multi-wheelset responses for a moving vehicle with multi degrees of freedom. • The nodal distribution method is capable of computing single-DOF wheelset response from multi wheelset responses. • The enhanced integration algorithm can efficiently compute the wheelset contact response. • The contact response enables bridge frequencies to be extracted without the interference from vehicle's frequencies. • The present method excels in accuracy, efficiency and robustness. This paper presents for the first time a top-down procedure for calculating the multi contact responses from the response of a multi DOF vehicle (containing two bogies and four wheelsets), which can be measured or simulated. Two key steps are involved. First, the nodal distribution method was devised for distributing the vehicle's responses to those of the four wheelsets. Then by treating the wheelset as a single-DOF system, the contact response is calculated exactly by the enhanced integration algorithm for each time step. Two scenarios are studied. In Scenario 1, the vehicle is kept stationary on the rails, but excited differently via the contact points, by which the transmission of vibration from the wheelsets up to the vehicle components and down again by the present method is validated. In Scenario 2, the vehicle is set to move over a simple bridge, by which the contact responses are shown to outperform the vehicle's responses in extracting the bridge frequencies, due to the fact that the vehicle's frequencies were totally eliminated. In addition, the present method has been demonstrated to be of excellent accuracy, efficiency and robustness in each application. [ABSTRACT FROM AUTHOR]

This study explores the concept of rocking foundations to mitigate damage during seismic events. By weakening the footing intentionally, the foundation acts as a "fuse" to prevent plastic hinges from forming in columns. Shake table experiments were conducted on a lightweight prototype deck mass-column-footing model founded on a fine, medium-dense sand, in two states of nearly dry and saturated. Kinetic energy dissipation, hysteresis, and decay are examined for various structure masses, for two nominal low and high motion frequencies. Findings suggest that energy dissipation is higher in saturated sands ― as compared to nearly dry and despite the absence of liquefaction ― due to fluctuating pore water pressure and a suction effect that evolves beneath foundations' edge. Where the substrate retains its original porosity, flow of water and subsequent damping becomes pivotal mechanisms to enable the rocking motion. In dry sands, energy dissipation occurs mainly through rotation, and enhances with motion frequency (from testing 3–5 Hz). In saturated sands, energy dissipation occurs predominantly through plastic settlement, and becomes less effective with motion frequency. Lighter structures experience greater rotational movement, especially in the case of dry sands. That enhanced rotational movement is drove by lower rotational stiffness. Overall, lighter structures facilitate the re-centring of the foundation upon rocking motion. • Mid-rise SDOF deck mass-column-footing model on shake table. • Combined effect of mass, saturation, and frequency on rocking mechanisms. • Emphasis on free decay, hysteresis, pore pressures and damping. • Departure from the broadly agreed increasing peak rotation upon saturation. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWCNTs) can be applied in a wide range of fields owing to their excellent mechanical rigidity, electrical conductivity, and thermal conductivity. However, their application is limited because of their strong van der Waals forces and poor dispersion owing to their hydrophobic properties. To address this problem, ultrasonic dispersion technology has been used in the industry. However, very few studies have investigated the surface damage or effectiveness of the surfactants of SWCNTs with a focus on the frequencies of specific ultrasonic equipment. In this study, the dispersibility of SWCNTs at frequencies of 270, 400, and 700 kHz was investigated using a new focused ultrasonic instrument. The dispersion stability of the samples was analyzed according to each frequency, and the SWCNT surface was studied in detail using field-emission transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The adsorption of the polymeric surfactant to the SWCNT was most observed at 270 kHz, and the dispersion stability after processing at this frequency was better than that of the other samples. Therefore, the frequency of the ultrasonic intensity has a direct effect on the surface modification of SWCNTs. [Display omitted] • Single-walled carbon nanotubes (SWCNTs) are dispersed in water via ultrasonication. • Ultrasonic frequencies of 270, 400, and 700 kHz are used for SWCNT dispersion. • Optimal adsorption of the surfactant to SWCNTs occurred at 270 kHz. • The frequency of ultrasonic intensity directly impacts the surface damage of SWCNTs. • A lower ultrasonic frequency results in a higher cavitation intensity. [ABSTRACT FROM AUTHOR]

To promote the application of Fe-based amorphous coating (AMC)-protected magnesium alloys in fretting wear conditions, a Fe-based AMC with a thickness of about 164 μm was deposited on AZ31B magnesium alloy substrate by detonation spraying. The microstructure and fretting wear behaviors against GCr15 counterpart ball in different frequencies of the Fe-based AMC were studied in detail. The results show that the Fe-based AMC has a substantially complete amorphous structure, the porosity and surface hardness are ≤1.2 vol %, and 764.7 ± 37.5 Hv 0.1 , respectively. Therefore, the Fe-based AMC presents excellent fretting wear resistance, and its wear rate is almost 1/10 of that of AZ31B magnesium alloy, and 1/5 of that of high-velocity oxygen-fuel sprayed 316L stainless steel coating on AZ31B magnesium alloy substrate. The fretting wear behavior of Fe-based AMC was found to be sensitive to the fretting frequency: as the frequency increases from 5 to 100 Hz, the average steady-state friction coefficient increases from 0.77 to 1.07, but the wear rate exhibits an anomalous phenomenon, decreasing from 5.26 × 10−5 mm3N−1m−1 to 3.47 × 10−5 mm3N−1m−1. The improvement in wear rate is mainly attributed to the formation of an oxygen-rich river-like friction layer on the worn surface as the transient contact temperature increases with frequency, effectively suppressing delamination wear. Additionally, the occurrence of high transient frictional temperatures at high frequencies leads to evident crystallization within the coating, accompanied by the formation of nanocrystals, oxide films, and a large area river-like friction layer consisting of debris-compacted layers, which strengthens the Fe-based AMC. Consequently, the wear mechanism changes from delamination wear and abrasive wear at low frequencies to oxidative wear and adhesive wear at high frequencies, resulting in superior fretting wear resistance of the Fe-based AMC at high frequencies. • The synergistic effect of crystalline and oxidized phases increase the average microhardness of the worn surface. • The friction coefficient is positively correlated with fretting wear frequency, while the wear rate is opposite. • The wear mechanism transitions from delamination and abrasive wear to adhesive wear and oxidative wear. [ABSTRACT FROM AUTHOR]