Relative Low Frequency Research Articles

High-efficiency, single-frequency, polarized thulium-doped silica fiber lasers.

We report on single-frequency, linearly polarized, high-concentration thulium-doped silica fiber-distributed Bragg reflector lasers operating at wavelengths between 1908 and 2050 nm with high efficiencies up to 48% and high powers up to 1 W. Low relative power noise and frequency noise are demonstrated using a low-noise pump diode.

The Attitude of Healthcare Providers and the General Population on the Concept of Do-Not-Resuscitate (DNR) Order in End-Stage Patients

Background: The do-not-resuscitate (DNR) order in end-stage patients constitutes a critical medical decision, directing healthcare providers to withhold cardiopulmonary resuscitation (CPR) in the event of cardiopulmonary arrest upon the patient's request. Objectives: This study aims to analyze the attitudes of healthcare providers and the general population toward the concept of DNR orders in end-stage patients. Methods: Conducted from September 2021 to May 2022, this cross-sectional study aimed to gauge the attitudes of healthcare providers and the general population toward DNR orders in end-stage patients using a questionnaire assessing attitudes toward DNR. The research population included healthcare providers—physicians and nurses—from healthcare centers affiliated with Iran University of Medical Sciences, selected through convenience sampling, and the general population comprising individuals frequenting parks near these healthcare centers within the relevant municipal districts. Results: Among the 164 participating healthcare providers, 139 (84.8%) were female. Participants' ages ranged from 21 to 57 years, with an average age of 36.78 ± 7.79 years. The study found that healthcare providers had a significantly higher average attitude score toward DNR (29.85 ± 9.46) compared to the general population (27.08 ± 9.78). Healthcare providers with adequate financial status exhibited a more positive attitude toward DNR in end-stage patients compared to those with excellent or poor economic status (P = 0.001). Additionally, the relative frequency of individuals experiencing a poor prognosis of disease was significantly lower among healthcare personnel than the general population (P = 0.018). Healthcare providers without family members or friends in their end-stage of life demonstrated a more favorable attitude toward DNR for these patients (P = 0.001). Conclusions: The study revealed that healthcare providers exhibited a significantly more positive attitude toward DNR compared to the general population. Furthermore, healthcare providers experienced a lower relative frequency of individuals facing a poor prognosis of disease compared to the general population. However, the relative frequency of experiencing family members or friends in the end stage did not significantly differ between healthcare providers and the general population. Healthcare providers with less than 2 years or more than 20 years of experience in the medical field demonstrated a more positive attitude toward DNR.

Analysis of the relative frequencies of the multipartite BNYVV genomic RNAs in different plants and tissues.

Multipartite virus genomes are composed of two or more segments, each packaged into an independent viral particle. A potential advantage of multipartitism is the regulation of gene expression through changes in the segment copy number. Soil-borne beet necrotic yellow vein virus (BNYVV) is a typical example of multipartism, given its high number of genomic positive-sense RNAs (up to five). Here we analyse the relative frequencies of the four genomic RNAs of BNYVV type B during infection of different host plants (Chenopodium quinoa, Beta macrocarpa and Spinacia oleracea) and organs (leaves and roots). By successfully validating a two-step reverse-transcriptase digital droplet PCR protocol, we show that RNA1 and -2 genomic segments always replicate at low and comparable relative frequencies. In contrast, RNA3 and -4 accumulate with variable relative frequencies, resulting in distinct RNA1 : RNA2 : RNA3 : RNA4 ratios, depending on the infected host species and organ.

Microbiota characterization throughout the digestive tract of horses fed a high-fiber vs. a high-starch diet.

Diet is one of the main factors influencing the intestinal microbiota in horses, yet a systematic characterization of the microbiota along the length of the digestive tract in clinically healthy horses, homogenous for age and breed and receiving a specific diet is lacking. The study used 16S rRNA amplicon sequencing to characterize the microbiota of the intestinal tracts of 19 healthy Bardigiano horses of 14.3 ± 0.7 months of age fed one of two diets. Nine horses received a high-starch diet (HS), and ten horses received a high-fiber diet (HF). After 129 days, the horses were slaughtered, and samples were collected from the different intestinal tract compartments. The microbiota alpha diversity indices were lower in the caecum, pelvic flexure and right dorsal colon of the horses fed the HS diet (False Discovery Rate, FDR < 0.05). The values of beta diversity indicated significant compositional differences between the studied intestinal tract compartments according to the diet received (FDR < 0.05). At the lower taxonomic level (genus or family), the HS diet was associated with a higher relative frequency of Enterobacteriaceae within the small intestine (jejunum and duodenum) (FDR < 0.05). Within the hindgut (caecum and sternal flexure), the HS diet was associated with lower relative frequencies (i.e., a smaller core community) of bacteria belonging to Fibrobacteraceae and Prevotellaceae (FDR < 0.05). Moreover, horses fed the HS diet displayed a higher relative abundance of Streptococcus in the caecum (FDR < 0.05) and Fusobacterium in the sternal flexure (FDR < 0.05), both of which are pathogenic bacteria responsible for inflammation diseases. Samples collected from the pelvic flexure and rectum of horses fed the HS diet showed significantly higher relative frequencies of Succinivibrionaceae (FDR < 0.05) - amylolytic bacteria associated with acidosis. The relative frequencies of the Lachnospiraceae and Ruminococcaceae were lower in the feces collected from the rectum of horses receiving the HS diet vs. HF diet, indicating smaller core communities of these bacteria (FDR < 0.05). Fibrous diets should be promoted to prevent dysbiosis of the microbiota associated with high-starch diet.

Sitatunga (Tragelaphus spekii) food sources and habitat use in Marsh–Savannah‐cultivation mosaics

AbstractWetland conversion threatens wetland specialists by reducing their core habitat. The sitatunga is a wetland specialist with declining populations. However, knowledge of sitatunga ecology and threats is limited, particularly outside protected areas. We examined sitatunga food sources, and habitat use in undisturbed Marshes and Marsh–Savannah transition blocks, and a Cultivated (disturbed) block in River Mayanja wetland, central Uganda. We recorded indirect indices and sightings of sitatunga along a 10 km transect in each block, and surveyed food sources in 34 plots along the transects. Our results indicate that the indices and sightings of Sitatunga had lower relative frequency in the Cultivated than in the Marshes and Marsh–Savannah transition blocks. Sitatunga feed on 39 plant species in 13 families and six growth forms; grasses, herbs, sedges, climbers, shrubs and water weeds. Cyperus papyrus, Echinochloa pyramidalis, Leersia hexandra accounted for 58% of sitatunga food sources. There were more individuals and species with Sitatunga feeding activity in the Marshes and Marsh–Savannah transition blocks than in the Cultivated block. Our results show that sitatunga habitat use and food sources are constrained in disturbed habitats while threats are intensified. To maintain wetland integrity and stability of sitatunga populations, stakeholders need to address wetland encroachment.

Perceptual dimensions of fan sounds with different tonal characteristics

Fan noise is a common tonal noise source in people's everyday life. While tonal sounds at high frequencies often contribute to annoyance, the perception and evaluation of low-frequency tones is not fully understood. In the present study, the perceptual dimensions of 24 tonal prototype fan sounds were explored using a semantic differential consisting of 21 adjective scales that were rated by 40 participants. The synthesized sounds had the same sound pressure level of 55 dB(A) but differed in fundamental frequency and spectral envelope of the embedded tonal signatures Using a factor analysis, four perceptual dimensions were found that explain 59 % of the variance. Fan sounds with a fundamental frequency of 60 Hz were rated to be more "humming" (1st dimension) and more "pleasant" (2nd dimension) but less "buzzing" and less "beeping" (3rd dimension) in comparison to sounds with higher fundamental frequencies of 180 Hz and 300 Hz. An analysis of the relationships between the adjective scales and psychoacoustic metrics show that the "humming" ratings were highly correlated to a metric describing the relative contribution of low frequencies to the overall loudness. In contrast, psychoacoustic sharpness and tonality had smaller correlation coefficients with the "humming" ratings.

The macroevolutionary dynamics of activity pattern in mammals: Primates in context

Activity pattern has played a prominent role in discussions of primate evolutionary history. Most primates are either diurnal or nocturnal, but a small number are active both diurnally and nocturnally. This pattern—cathemerality—also occurs at low frequency across mammals. Using a large sample of mammalian species, this study evaluates two macroevolutionary hypotheses proposed to explain why cathemerality is less common than diurnality and nocturnality: 1) that cathemeral lineages have higher extinction probabilities (differential diversification) and 2) that transitions out of cathemerality are more frequent, making it a less persistent state (differential state persistence). Rates of speciation, extinction, and transition between character states were estimated using hidden-rates models applied to a phylogenetic tree containing 3013 mammals classified by activity pattern. The models failed to detect consistent differences in diversification dynamics among activity patterns, but there is strong support for differential state persistence. Transition rates out of cathemerality tend to be much higher than transition rates out of nocturnality. Transition rates out of diurnality are similar to those for cathemerality in most clades, with two important exceptions: diurnality is unusually persistent in anthropoid primates and sciurid rodents. These two groups combine very low rates of transition out of diurnality with high speciation rates. This combination has no parallels among cathemeral lineages, explaining why diurnality has become more common than cathemerality in mammals. Similarly, the combination of rates found in anthropoids is sufficient to explain the low relative frequency of cathemerality in primates, making it unnecessary to appeal to high extinction probabilities in cathemeral lineages in this clade. These findings support the hypothesis that the distribution of activity patterns across mammals has been influenced primarily by differential state persistence, whereas the effect of differential diversification appears to have been more idiosyncratic.

Professional and ethical approaches to characterize complications in elective spinal neurosurgery. Never events in lumbar discectomy

Any surgical intervention is associated with the possible development of complications. Surgical complications are traditionally an unpopular topic for discussion, but in recent decades they have received increased attention, due to both medical and economic factors. This review discusses the general concepts that characterize the negative consequences of surgical interventions in spinal neurosurgery: complications, adverse events, sentinel events, never events, collateral adverse outcomes. Classifications are given that allow systematizing these negative phenomena. Surgical treatment of the lumbar disk herniation is the most frequently performed spinal surgery. The true number of lumbar discectomies is difficult to estimate because this procedure is often not an isolated surgical intervention, but a step in a larger one. Being a routine surgical procedure, discectomy, performed in one or another way depending on the preferences of the surgeon and available equipment, is characterized by a rather low relative frequency of adverse events and complications compared to other types of spinal surgery. However, due to the significant number of interventions, the absolute figures may present a medical and economic problem. Most authors refer to the classic triad of “wrong level, wrong side, wrong patient” and foreign bodies in the area of surgical intervention as obvious medical errors. Damage to the intestine or peritoneum, trauma to the great vessels and trauma to the nerve roots are considered serious complications, but not always medical errors. The other most commonly reported adverse events of lumbar discectomy are durotomy, neurological complications, surgical wound complications, recurrent disc herniation, and reoperation. Until now, no clear classification of the negative consequences of lumbar discectomy, which would allow to verify the relationship between intraoperative adverse events (both surgical and anesthetic) and postoperative complications has been developed. In addition, it is extremely difficult, based on the criteria available in the literature, to identify a medical error in a number of iatrogenic complications, which requires further comprehensive study of the problem, since it has not only medical, but also legal consequences.

A Case Series of Dentigerous Cyst in Paediatric Patients at Our Tertiary Institution.

Dentigerous cysts involves erupted or developing teeth in decreasing order of frequency as mandibular third molars, the maxillary canines, the maxillary third molars with rare involvement of the central incisors & are usually asymptomatic but becomes symptomatic with symptoms such as swelling, mild sensitivity, tooth mobility and displacement when it reaches size > 2cm in diameter. Dentigerous cysts are seen most commonly in 20-30years age group with relative low frequency in children with proportion of 4-9% of these cysts occur in the first 10years after birth. Hospital based study conducted in the Department of ENT at Ashwini Rural medical college & Hospital, Solapur in which we have reported a series of three cases of dentigerous cyst in paediatric patients. Dentigerous Cysts in our study were associated with maxillary permanent lateral incisor, mandibular permanent premolar, Mandibular second molar tooth in pediatric age group. Provisional diagnosis of Dentigerous cyst based on clinical, radiological & biochemical study but Histopathological examination confirms the diagnosis. Dental orthopentamogram aids in diagnosing and localizing the Dentigerous cyst and ct face in all views helps to see bony effects and complications due to expansion of Dentigerous cyst. Enucleation of the cystic lesion followed by extraction of the offending teeth is a suitable treatment modality for Dentigerous cyst associated with maxilla and mandible giving adequate balance between complete removal of cyst & giving chance for eruption of unerupted teeth.

The Path to Translating Focus of Attention Research Into Canadian Physiotherapy, Part 1: Physiotherapists’ Self-Reported Focus of Attention Use Via a Study-Specific Questionnaire

The focus of attention literature has shown robust findings for the benefits of providing statements that focus on the movement effect or outcome (external focus of attention [EFOA]) as opposed to focusing on the movement kinematics (internal focus of attention). Observational studies, however, have revealed that physiotherapists use fewer EFOA statements than internal focus of attention statements in their practice. Most evidence in this regard has been from non-Canadian physiotherapists working in stroke rehabilitation; consequently, we sought to examine whether Canadian physiotherapists working with various rehabilitation populations also use EFOA statements to a lesser extent than internal focus of attention statements. The “Therapists’ Perceptions of Motor Learning Principles Questionnaire (TPMLPQ)” was thus designed and data from 121 Canadian physiotherapists showed low relative frequencies of EFOA use (31.3% ± 14%) averaged across six hypothetical scenarios. A higher EFOA was reported, however, for two of the six scenarios: a functional reaching scenario (55.5% ± 37.0%) and pelvic floor task (65.6% ±32.9%). This data suggest that the findings of EFOA benefits have not been widely translated into Canadian physiotherapy settings; furthermore, the findings of the scenario-dependency warrant future investigation into factors, such as task characteristics, that may influence physiotherapists’ FOA use.

Significant antimicrobial-producing vegetation uniquely shapes the stormwater biofilter microbiome with implications for enhanced faecal pathogen inactivation

Biofilters demonstrate promising yet inconsistent removal of faecal pathogens from stormwater. Antimicrobial-producing plants represent safe, inexpensive biofilter design features which can significantly enhance faecal microbe treatment. The microbiota naturally inhabiting biofilters have additionally been established as key mediators of faecal microbe inactivation. To date, however, it remains unknown: (1) to what extent plants, including significant antimicrobial-producing plants, influence the biofilter microbiome; and (2) how this in turn impacts faecal microorganism survival/die-off. The present study employed 16S rRNA sequencing to examine these relationships throughout the soil profiles of differently vegetated biofilters over time. It was found that plants had subtle but significant influences on the composition and structure of resident biofilter bacterial communities, with varying impacts observed throughout biofilter profiles. Bacterial communities inhabiting biofilters comprising significant antimicrobial-producing plants demonstrated distinct compositional and taxonomic differences relative to other configurations. In particular, compared to other biofilters, the best-performing configuration for faecal bacterial treatment, Melaleuca linariifolia (significant antimicrobial-producing plant), exhibited both higher and lower relative frequencies of putative faecal bacterial antagonists (e.g. Actinobacteria) and mutualists (e.g. certain Gammaproteobacteria), respectively. These preliminary findings suggest that antimicrobial plants may enhance populations of microbiota which suppress faecal bacterial survival, and highlight the plant-microbiome relationship as a novel area of focus for optimising biofilter performance.

Spectrum and implications of activating BRAF alterations in advanced prostate cancer (aPC).

220 Background: Activating genomic alterations (GA) in BRAF are rare in aPC and their impact on pathogenesis is poorly understood. However, emerging data suggest that these GA may represent clinically actionable targets (Fenor et al, Clin Transl Oncol, 2022). Using comprehensive genomic profiling (CGP) performed in a single commercial lab, we characterized the GA landscape of BRAF-activated tumors in aPC patients (pts). Methods: Tissue(N=15,864) and liquid (N=7,566) biopsies from aPC pts were profiled using FoundationOne CDx and FoundationOne Liquid CDx CGP assays, respectively. Each assay covers 324 cancer-related genes, including the full coding region of BRAF and introns 7-10, with additional sensitivity in exons 11-18 in the liquid assay. Activating GA were defined as hotspot missense mutations, in-frame indels in the kinase domain, or rearrangements (RE) that preserve the kinase domain. Tissue biopsies from non-aPC cancer types (N= 275,151) were used for comparison. Results: BRAF-activating GA were detected in 520/15,864 (3.3%) tissue biopsies: RE were the most common GA (243 samples, 1.5%), followed by K601E (101, 0.6%), and G469A (58, 0.4%). Median age of pts with BRAF-altered tumors was 69 (interquartile range 63-76), compared to 68 for BRAF wild-type (interquartile range 62-74). Rearrangement breakpoints occurred most frequently in intron 8 (37%), intron 9 (28%), intron 10 (20%), and intron 7 (13%). The most common RE were BRAF N-terminal truncations removing the auto-inhibitory domain (22%), SND1-BRAF fusions (13%), intragenic BRAF deletions of the auto-inhibitory domain (12%), and TMPRS22-BRAF fusions (5%). When studying cases with BRAF-activating GA compared to wild-type, we noted a larger proportion of CDK12 mutations (9.2% vs 5.2%, p=0.018), and a depletion of TMPRSS2-ERG fusions (11% vs 32%, p&lt;0.0001), PTEN GA (17% vs 31%, p&lt;0.0001), and APC GA (4.4% vs 8.9%, p = 0.018); alterations in AR occurred at similar rates (13% vs 13%, p=1.0). In liquid samples, overall BRAF GA were slightly less common (187/7566, 2.5%): 65 (0.9%) RE, 33 (0.4%) K601E, 12 (0.2%) G469A. Examining BRAF-altered samples across all cancer types, aPC had the highest proportions of RE (46%) and one of the lowest frequencies of V600E (0.1%). Conclusions: Activating BRAF alterations are detected in ~3% of aPC, with frequent BRAF-SND1 fusions. BRAF RE represent almost half of aPC BRAF GA, the highest fraction observed across a pan-tumor dataset. In addition, we detected a higher incidence of concurrent CDK12 GA and a lower relative frequency of concurrent PTEN, APC, and TMPRSS2-ERG GA. These findings suggest that genetic activation of BRAF in aPC pts may contribute to tumorigenesis and supports further clinical investigation of therapeutics targeting the MAPK pathway in this molecular subtype.

Free-running Yb:KYW dual-comb oscillator in a MOPA architecture.

Single-cavity dual-combs comprise a rapidly emerging technology platform suitable for a wide range of applications like optical ranging, equivalent time sampling, and spectroscopy. However, it remains a challenging task to develop a dual-comb system that exhibits low relative frequency fluctuations to allow for comb line resolved measurements, while simultaneously offering high average power and short pulse durations. Here we combine a passively cooled and compact dual-comb solid-state oscillator with a pair of core-pumped Yb-fiber-based amplifiers in a master-oscillator power-amplifier (MOPA) architecture. The Yb:KYW oscillator operates at 250 MHz and uses polarization multiplexing for dual-comb generation. To the best of our knowledge, this is the first demonstration of a single-cavity dual-comb based on this gain material. As the pulse timing characteristics inherent to the oscillator are preserved in the amplification process, the proposed hybrid approach leverages the benefit of both the ultra-low noise solid-state laser and the advantages inherent to fiber amplifier systems such as straight-forward power scaling. The amplifier is optimized for minimal pulse broadening while still providing significant amplification and spectral broadening. We obtain around 1 W of power per output beam with pulses then compressed down to sub-90 fs using a simple grating compressor, while no pre-chirping or other dispersion management is needed. The full-width half-maximum (FWHM) of the radio-frequency comb teeth is 700 Hz for a measurement duration of 100 ms, which is much less than the typical repetition rate difference, making this passively stable source well-suited for indefinite coherent signal averaging via computational phase tracking.

Abstract 40: Gut Dysbiosis Exacerbates Neuroinflammation By Activation Of B Cells In A Mouse Model Of Cerebral Amyloid Angiopathy

Introduction: Cerebral amyloid angiopathy (CAA) is a debilitating disease that leads to intracerebral hemorrhage, white matter disease, and progressive cognitive decline in patients &gt;50 years of age. Studies investigating the neuroimmune landscape in CAA are sparse. Here, we investigate the role of B cells in CAA. Methods: Pre-symptomatic (2 months) and symptomatic (10-13 months) male Tg-SwDI mice (CAA mice) harboring Swedish, Dutch, and Iowa mutations of human amyloid precursor protein (APP) were used as a mouse model of CAA. Single cells isolated from the brain were analyzed using flow cytometry to characterize neuroinflammation and cognitive impairment was assessed using fear conditioning. Fecal microbiota transplantation (FMT) of the microbiome from pre-symptomatic and symptomatic CAA mice into young wild-type (WT) recipient male mice (2 months) was performed to determine if CAA-induced gut dysbiosis contributes to brain B cell activation. Results: Cognitive assessment using fear conditioning indicated a significantly lower delta inactive state in symptomatic CAA mice (n=4/grp, * P &lt;0.05) compared to pre-symptomatic CAA mice. Symptomatic CAA mice had a significantly lower relative frequency of microglia (CD45 int CD11b + , n=11-13/grp, ** P &lt;0.01) and significant infiltration of lymphoid (CD45 high CD11b - , n=11-13/grp, *** P &lt;0.001) cells in the brain, as compared to pre-symptomatic CAA mice. Symptomatic CAA mice had significantly higher B cells in the brain (n=10-13/grp, * P &lt;0.05. Further, activated B cells as assessed by the expression level of CD11b showed that CD11b + B cells were significantly higher in the symptomatic CAA brain (n=10-13/grp, * P &lt;0.05). Interestingly, this phenotype was recapitulated in young WT recipients reconstituted with pre-symptomatic CAA and CAA microbiome through FMT. Young WT recipients with CAA biome had significantly higher relative frequency of CD11b + B cells in the brain compared to young recipients with pre-CAA biome (n=7-9/grp, *** P &lt;0.001). Conclusions: These results suggest that the aberrant activation of B cells in the brain may be influenced by CAA-induced gut dysbiosis. Further investigations upon the functional role of CD11b + B cells in the vascular deposition of Aβ are warranted.

Performance evaluation of asphalt mixture using brake pad waste as aggregate

Utilizing brake pad waste (BPW) in asphalt mixture can not only reduce the consumption of natural mineral material, but also alleviate the environmental pollution problem caused by such solid waste. This paper concentrates on the feasibility and strategy of using BPW as aggregate in asphalt mixture. Firstly, BPW aggregate within five different particle sizes were separately used to replace the limestone aggregate or filler with different proportions (25%, 50%, 75% and 100%) in asphalt mixture by the volume control method. The corresponding optimum asphalt contents of 21 kinds of asphalt mixtures were determined by the Marshall design procedure. Due to its high asphalt-absorption, BPW aggregate would increase the optimum asphalt content of asphalt mixture, which depends on the particle size of BPW aggregate. To meet the Chinese Standard Specification for asphalt mixture, the maximum substitution proportions for the BPW aggregates of 0–0.075 mm, 0.075–2.36 mm, 2.36–4.75 mm, 4.75–9.5 mm, 9.5–16 mm were 75%, 50%, 25%, 100%, and 100%, respectively. On this basis, BPW mixture simultaneously using the BPW aggregate with different sizes and the corresponding maximum substitution proportions were prepared and evaluated by a series of laboratory tests as well. Results implied that BPW mixture (BPW-M) outperformed the limestone asphalt mixture (Control-M) in term of the moisture stability, the high-temperature performance, the low-temperature property, and the fatigue life. Furthermore, dynamic modulus test results indicated that BPW-M mixture was more stiffness at relative low frequency (high temperature) and more flexible at relative high frequency (low temperature). Overall, this study verifies the feasibility and provides a reference datum of using BPW materials as aggregate in asphalt mixture.

The mutation features and geographical distributions of the surface glycoprotein (S gene) in SARS-CoV-2 strains: A comparative analysis of the early and current strains.

The surface glycoprotein (S protein) of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) was used to develop coronavirus disease 2019 (COVID‐19) vaccines. However, SARS‐CoV‐2, especially the S protein, has undergone rapid evolution and mutation, which has remained to be determined. Here, we analyzed and compared the early (12 237) and the current (more than 10 million) SARS‐CoV‐2 strains to identify the mutation features and geographical distribution of the S gene and S protein. Results showed that in the early strains, most of the loci were with relative low mutation frequency except S: 23403 (4486 strains), while in the current strains, there was a surge in the mutation strains and frequency, with S: 23403 constantly being the highest one, but tremendously increased to approximately 1050 times. Furthermore, D614 (S: 23403) was one of the most highly frequent mutations in the S protein of Omicron as of March 2022, and most of the mutant strains were still from the United States, and the United Kingdom. Further analysis demonstrated that in the receptor‐binding domain, most of the loci with low mutation frequency in the early strains, while S: 22995 was nowadays the most prevalent loci with 3 122 491 strains in the current strains. Overall, we compare the mutation features of the S region in SARS‐CoV‐2 strains between the early and the current stains, providing insight into further studies in concert with emerging SARS‐CoV‐2 variants for COVID‐19 vaccines.

Low frequency (&amp;lt;1 MHz) transducers for intravenous sonothrombolysis

Venous embolism is a great challenge in the treatment of a wide range of diseases, including cardiovascular diseases and cancers. Ultrasound-mediated thrombolysis (sonothrombolysis) presents a promising treatment of venous embolism. In this paper, miniature ultrasound transducers with frequencies ranging from 250 kHz to 800 kHz were developed for microbubble/nanodroplet-mediated intravenous sonothrombolysis tests. Relative low frequency (e.g., &amp;lt;1 MHz) is preferred because of the findings that cavitation plays an important role in sonothrombolysis, and microbubble-associated cavitation events can be enhanced at low frequencies. Small aperture (e.g. &amp;lt;2 mm × 2 mm) low-frequency transducers are usually known with high electrical impedance (e.g., &amp;gt;1000 Ω), which is not preferred for efficient electromechanical transduction. To address this challenge, multilayer acoustic stacks were designed, fabricated, and characterized. The measured electrical impedance of these stacks is mostly closer to 50 Ω, and the peak negative pressure is higher than 1MPa. These small aperture transducers were then used in in vitro- thrombolysis tests with unretracted and retracted blood clots, showing promising lysis rates. Other techniques such as laser ultrasound transducers, vortex wave generation, and magnetic microbubbles were also investigated for thrombolysis tests.

Parental preferences for seizure detection devices: Adiscrete choice experiment.

ObjectivePrevious studies identified essential user preferences for seizure detection devices (SDDs), without addressing their relative strength. We performed a discrete choice experiment (DCE) to quantify attributes' strength, and to identify the determinants of user SDD preferences.MethodsWe designed an online questionnaire targeting parents of children with epilepsy to define the optimal balance between SDD sensitivity and positive predictive value (PPV) while accounting for individual seizure frequency. We selected five DCE attributes from a recent study. Using a Bayesian design, we constructed 11 unique choice tasks and analyzed these using a mixed multinomial logit model.ResultsOne hundred parents responded to the online questionnaire link; 49 completed all tasks, whereas 28 completed the questions, but not the DCE. Most parents preferred a relatively high sensitivity (80%–90%) over a high PPV (>50%). The preferred sensitivity‐to‐PPV ratio correlated with seizure frequency (r = −.32), with a preference for relative high sensitivity and low PPV among those with relative low seizure frequency (p = .04). All DCE attributes significantly impacted parental choices. Parents expressed preferences for consulting a neurologist before device use, personally training the device's algorithm, interaction with their child via audio and video, alarms for all seizure types, and an interface detailing measurements during an alarm. Preferences varied between subgroups (learning disability or not, SDD experience, relative low vs. high seizure frequency based on the population median).SignificanceVarious attributes impact parental SDD preferences and may explain why preferences vary among users. Tailored approaches may help to meet the contrasting needs among SDD users.

Comparison of the oral microbial composition between healthy individuals and periodontitis patients in different oral sampling sites using 16S metagenome profiling.

The purpose of this study was to compare the microbial composition of 3 types of oral samples through 16S metagenomic sequencing to determine how to resolve some sampling issues that occur during the collection of sub-gingival plaque samples. In total, 20 subjects were recruited. In both the healthy and periodontitis groups, samples of saliva and supra-gingival plaque were collected. Additionally, in the periodontitis group, sub-gingival plaque samples were collected from the deepest periodontal pocket. After DNA extraction from each sample, polymerase chain reaction amplification was performed on the V3-V4 hypervariable region on the 16S rRNA gene, followed by metagenomic sequencing and a bioinformatics analysis. When comparing the healthy and periodontitis groups in terms of alpha-diversity, the saliva samples demonstrated much more substantial differences in bacterial diversity than the supra-gingival plaque samples. Moreover, in a comparison between the samples in the case group, the diversity score of the saliva samples was higher than that of the supra-gingival plaque samples, and it was similar to that of the sub-gingival plaque samples. In the beta-diversity analysis, the sub-gingival plaque samples exhibited a clustering pattern similar to that of the periodontitis group. Bacterial relative abundance analysis at the species level indicated lower relative frequencies of bacteria in the healthy group than in the periodontitis group. A statistically significant difference in frequency was observed in the saliva samples for specific pathogenic species (Porphyromonas gingivalis, Treponema denticola, and Prevotella intermedia). The saliva samples exhibited a similar relative richness of bacterial communities to that of sub-gingival plaque samples. In this 16S oral microbiome study, we confirmed that saliva samples had a microbial composition that was more similar to that of sub-gingival plaque samples than to that of supra-gingival plaque samples within the periodontitis group.

Ten-Year Clinical Outcomes in Patients With Acute Coronary Syndrome Treated With Biodegradable, Permanent-Polymer or Polymer-Free Drug-Eluting Stents.

This study aimed to compare 10-year clinical outcomes in patients with acute coronary syndrome (ACS) treated with new-generation biodegradable-polymer (BP-DES), polymer-free (PF-DES), and permanent-polymer drug-eluting stents (PPDES). We analyzed 10-year clinical outcomes for 2042 patients with ACS enrolled in the ISAR-TEST 4 and ISAR-TEST 5 randomized controlled trials. Patients were divided into 3 groups: new-generation PP-DES, BP-DES, and PF-DES. Endpoints of interest included a device-oriented composite endpoint (DOCE) and a patient-oriented composite endpoint (POCE) at 10 years. BP-DES as compared with PP-DES demonstrated a lower DOCE frequency, but this did not meet statistical significance (BP-DES vs PP-DES, 35.4% vs 41.5%, respectively; adjusted hazard ratio (HR), 0.83; 95% confidence interval [CI], 0.68-1.00; P=.05). There was a significantly lower POCE frequency in patients treated with BP-DES compared with PP-DES (65.3% vs 69.0%, respectively; HR, 0.86; 95% CI, 0.75-0.99; P=.04). The relative frequency of the DOCE (41.4% vs 41.5%; HR, 0.97; 95% CI, 0.83-1.15; P=.76) and the POCE (66.8% vs 69.0%; HR, 0.99; 0.87-1.12; P=.82) were comparable in patients treated with PF-DES and PP-DES. In patients with ACS, BP-DES were associated with a lower relative frequency of a POCE compared with new-generation PP-DES at 10 years. The relative frequencies of both device- and patient-related outcomes were comparable in patients treated with PF-DES and PP-DES at 10 years.