Predicting influenza in China from October 1, 2023, to February 5, 2024: A transmission dynamics model based on population migration.

Introduction: Since November 2023, influenza has ranked first in reported cases of infectious diseases in China, with the outbreak in both northern and southern provinces exceeding the levels observed during the same period in 2022. This poses a serious health risk to the population. Therefore, short to medium-term influenza predictions are beneficial for epidemic assessment and can reduce the disease burden. Methods: A transmission dynamics model considering population migration, encompassing susceptible-exposed-infectious-asymptomatic-recovered (SEIAR) was used to predict the dynamics of influenza before the Spring Festival travel rush. Results: The overall epidemic shows a declining trend, with the peak expected to occur from week 47 in 2023 to week 1 in 2024. The number of cases of A (H3N2) is greater than that of influenza B, and the influenza situation is more severe in the southern provinces compared to the northern ones. Conclusion: Our method is applicable for short-term and medium-term influenza predictions. As the spring festival travel rush approaches. Therefore, it is advisable to advocate for nonpharmaceutical interventions (NPIs), influenza vaccination, and other measures to reduce healthcare and public health burden.

Can pure cellulose nanofibril films replace polyolefins as water vapor barriers in packaging?

Despite significant research into cellulose nanofibril (CNF) films as substitutes to synthetic plastic materials, commercial applications remain very limited. One major hindrance is the poor water vapor barrier properties of CNF films compared to polyolefins, a critical property for product protection, such as food safety and preservation. To date, it is unknown whether full moisture barrier properties can be achieved with materials made by the assembly of nanofibers and fibrils. A comprehensive understanding of the effect of film structure on water vapor transport properties is required. Here, over 200 films were produced with a wide range of grammages from 30 g/m2 to 580 g/m2 by casting and spray deposition. Their structures were quantified by µCT and SEM and related to their water vapor transmission rates (WVTRs). Porosity and pore connectivity decreased with increasing film grammage, which correlates with the exponential decrease in WVTR. However, the WVTR plateaued at 30 g/m2day, indicating that the known open space and adsorption diffusion mechanisms cannot be fully eliminated by producing high grammage films. Pure cellulose nanofibril films therefore cannot replace polyolefins in packaging applications, requiring modifications such as coating and nanofillers.

Community dynamics and assembly is driven by environmental microbiota mediated by spatiotemporal distribution: The case of Daqu fermentation.

In almost all environments, microbial interaction is shaped by differences in environmental microbial transport, resulting in synergistic or antagonistic effects among community members. Unfortunately, the current understanding of how environmental microbiota affect spontaneous fermentation is very limited. Here, we selected Daqu workshops with different usage times (named X (60 years), Y (10 years), and Z (0 year)) as research model. The microbial contribution of raw material and environments to the microbiota of Daqu fermentation among workshops was compared, raw material microbiota contributed more bacterial genera (44.70 %-73.56 %) to the fermentation, and environmental microbiota contributed more fungal genera (10.09 %-99.76 %) to the fermentation. The deterministic assembly ratio and interaction intensity of workshop X were the highest, followed by Y and Z. We analyzed the relationship between environmental microbiota, fermentation microbiota, fermentation characteristics and flavor compounds. Environmental microbiota negatively drove the microbial diversity during fermentation (path coefficient = -1, P = 0.004), and further indirectly affected the community dynamics and assembly (path coefficient = -0.990, P < 0.001). Finally, community dynamics and assembly drove flavor compound diversity (path coefficient = 0.923, P < 0.001), it indicated the positive effect of environmental microbiota on flavor compound diversity. This work will help to understand the relationship between environmental microbiota and fermentation quality, supporting quality improvement of spontaneously fermented food in new workshop.

Isolation and Characterization of Exosomes from Ocular Samples.

Exosomes are microsize vesicles secreted by nearly all cells to the extracellular space. The vesicles transport cell signaling and communicate with other cells. Ultracentrifugation is the standard method to isolate exosomes from culture media or body fluid. Without ultracentrifuge, exosomes can be precipitated by polyethylene glycol or separated by size exclusion chromatography. After isolation, nanoparticle tracking analysis can help to estimate the size and concentration of exosome samples. Transmission electron microscopy can directly show the size and morphology of exosomes. Moreover, the sample should be characterized by the expression of several exosome biomarker proteins. Exosomal contents such as proteins and miRNAs could be profiled using appropriate technologies.

Buruli ulcer: An epidemiological update from Japan.

Japan is one of the rare non-tropical countries with documented cases of Buruli ulcer (BU). Mycobacterium ulcerans subsp. shinshuense has been identified as the causative agent. The first report of BU in Japan dates back to 1982, with sporadic reports thereafter. Recently, the number of cases has been on the increase, and 50 cases (57.7%) are from the past decade alone, out of a total of 87 cases reported to date. Japan's well-developed healthcare facilities play a crucial role in enabling detailed investigations and providing appropriate treatment for patients, contributing to a favorable prognosis. However, the rarity of the disease results in lack of awareness among healthcare professionals, leading to frequent delays in diagnosis. This article aims to offer an updated overview of BU cases in Japan and to raise awareness of BU among dermatologists and other healthcare professionals in a non-endemic setting.

Parental History of Childhood Maltreatment and Offspring Attachment Insecurity and Disorganization: Two Meta-Analyses.

Research findings have shown that parental history of childhood maltreatment (CM) increases the risk of insecure and disorganized attachment in offspring. However, the extent of the detrimental effects of childhood trauma on attachment in the next generation is unclear. The current meta-analyses aimed at synthesizing the available literature on the link between parental history of CM and offspring attachment insecurity and disorganization (with no restriction of offspring age). In total, 25 studies (23 unique samples; N = 2,592) comprising u = 61 effect sizes were included. Offspring age ranged from 12 to 79 months (Mweighted = 18.69; SDweighted = 11.53). Findings from two three-level random effects meta-analyses revealed a weak but significant combined effect of parental history of CM on child attachment insecurity (k = 20, u = 35, r = .06) and a non-significant effect on child attachment disorganization (k = 12, u = 26, r = .03). For the meta-analysis on disorganization, effect sizes were weaker in more recent studies, and trim and fill analyses provided evidence of publication bias. These findings provide a nuanced view of the intergenerational transmission of childhood trauma phenomenon, whereby parents' self-reported history of CM does not appear decisive for child attachment. Conclusions could not be drawn for specific types of CM because of the small number of studies. Research with more objective measures of parental exposure to CM is needed to gain a more comprehensive view of the possible intergenerational effects of CM on child attachment.

Is it really descemetocele? Morphology of extremely thin membrane that remained after severe corneal melting: a case report.

The aim of this study was to report transmission electron microscopic findings of a case with whole corneal descemetocele following infective corneal ulcer for the first time in literature. A 72-year-old male patient presented with infective corneal ulcer. After resolution of the infection, corneoscleral transplantation was performed. The excised very thin corneal membrane was processed for transmission electron microscopic examination. Transmission electron microscopic examination of the specimen revealed many layered structures that consisted of two different types of cells. The first type consisted of lighter staining polygonal cells, while the second consisted of elongated cells with relatively dense staining. All cells were connected with a large number of gap or adherens junctions with intercalation of the cell membranes of adjacent cells. A haphazard distribution of cytoplasmic microfilaments were also observed in all of the cell types. There was no evidence of the presence of endothelial cells throughout the specimen. There was also no evidence of Descemet membrane presence except for a small part adjacent to iris tissue that contained some melanosomes. Although we clinically diagnosed descemetocele, Descemet membrane was not present at the electron microscopic level, and thus, the expression "descemetocele" is inappropriate.

ß-asarone protects against age-related motor decline via activation of SKN-1/Nrf2 and subsequent induction of GST-4.

Decelerating motor decline is important for promoting healthy aging in the elderly population. Acorus tatarinowii Schott is a traditional Chinese medicine that contains ß-asarone as a pharmacologically active constituent. We found that ß-asarone can decelerate motor decline in various age groups of Caenorhabditis elegans, while concurrently prolonging their lifespan and modulating synaptic transmission. To understand the mechanisms of its efficacy in motor improvement, we investigated and discovered that mitochondrial fragmentation, a marker for aging, is delayed after ß-asarone treatment. Moreover, their efficacy is blocked by dysfunctional mitochondria. Corresponding to their role in regulating mitochondrial homeostasis, we found that SKN-1/Nrf2 and GST-4 are critical in the ß-asarone treatment, and they appear to be activated via the insulin/IGF-1 signaling pathway. Well-developed intestinal microvilli are required for this process. Our study demonstrates the efficacy and mechanism of ß-asarone treatment in age-related motor decline, contributing to the discovery of drugs for achieving healthy aging.

Negative and positive urgency as pathways in the intergenerational transmission of suicide risk in childhood.

Introduction: Parental suicide attempts and suicide death increase suicide risk in their offspring. High levels of impulsivity have been observed in families at high risk for suicide. Impulsivity, a highly heritable trait that is especially elevated in childhood, is frequently measured with the UPPS-P Impulsive Behavior Scale, which includes negative urgency, positive urgency, sensation seeking, premeditation, and perseverance. Our study examined the association between the UPPS-P facets and suicide ideation (without suicide attempts) and suicide attempts at baseline and first-time endorsement within the next two years in childhood. We also examined how the UPPS-P facets mediated the association between parental suicide attempts and suicide death and offspring first-time suicide ideation and attempts at follow-up. Methods: The sample was 9,194 children (48.4% female; 9-10 years old) from the Adolescent Brain Cognitive Development (ABCD) study, assessed yearly three times. At Time 1 (T1), caregivers reported on suicide attempts and suicide deaths (combined) of the biological parents. Caregivers and children reported on suicide ideation and attempts in the KSADS-PL DSM-5 at each time point, T1 and follow-up (T2 and/or T3). The Short UPPS-P Scale (child-report) assessed the impulsivity facets at T1, which were computed as latent variables. Results: At T1, 6.7% of children had a parent who had attempted or died by suicide. Most UPPS-P facets were associated with suicide ideation and attempts at T1 and T2/T3. In adjusted models, parental suicide attempts and suicide death were associated with offspring negative and positive urgency. In mediation models, parental suicide attempts and suicide death had an indirect effect on offspring first-time suicide ideation at T2/T3 through negative urgency (OR = 1.04; 95% CI, 1.01-1.08) and positive urgency (OR = 1.03, 95% CI, 1.01-1.05). Similar results were found for first-time suicide attempts at T2/T3. Discussion: Our findings support an impulsive pathway in the familial transmission of suicide risk. For all youth, interventions that target multiple UPPS-P facets may help prevent or reduce suicide risk. For offspring whose parents have attempted or died by suicide, clinicians should pay particular attention to children who impulsively act on extreme emotions, as they may be at higher suicide risk.

Mpox in UK households: estimating secondary attack rates and factors associated with transmission, May-November 2022.

We aimed to estimate the secondary attack rate of mpox among UK household contacts and determine factors associated with transmission to inform public health management of contacts, during the global outbreak in 2022. Information was collected via NHS and public health services and included age, gender, place of residence, setting, and type of contact. Aggregate information was summarized for the UK. Record level data was combined for England, Wales and Northern Ireland, and multivariable logistic regression was used to determine factors associated with transmission. The secondary attack rate among UK household mpox contacts was 4% (60/1 526). Sexual contact with the index case was associated with a 11-fold increase in adjusted odds of becoming a case in England, Wales, and Northern Ireland (95% CI 5.5-22, p < 0.001). Household contacts outside of London had increased odds compared to London residents (adjusted OR 2.9, 95%CI 1.6-5.4, p < 0.001), while female contacts had reduced odds of becoming a case (aOR: 0.41, 95% CI: 0.15-0.95). We found a low overall secondary attack rate among household mpox contacts with strong evidence of increased transmission risk associated with sexual contact. This evidence will inform the risk assessment of contacts and support prioritization of those with close intimate contact for follow up.

Microwave Vertebrae Strength Probe Development: Robust and Fast Phase Unwrapping Technique.

We have developed a new transmission-based, open-ended coaxial probe for assessing vertebrae strength during spinal fusion surgery. The approach exploits the fact that the probes are within the far field of each other implying that the phase varies linearly with respect to propagation distance. Determining the absolute phase is critical for recovering the associated tissue dielectric properties from which bone strength will be determined. Unfortunately, unwanted multi-path signals corrupt the signals at the lower end of the operating frequency range from which our conventional unwrapping strategy depends. Our new approach requires only three measurements within the prime frequency range and can be determined robustly with a minimum of computations. This will be vital to developing a commercial device since the signal levels will be extremely low power requiring longer than usual data acquisition times, which will be mitigated by measuring the data at only a few frequencies. Fast and efficient operation will be critical for clinical success.

Disinfectants efficacy in reducing pathogens related to health-care infection associated in universities hospitals of Gorgan, North of Iran.

BACKGROUND: Disinfection has a fundamental role in the control of pathogens in the hospital environment. This study was designed to assess the efficacy and functional impact of disinfectants in reducing pathogens related to healthcare associated infections (HAIs) in hospitals. METHODS: This observation study was conducted at three university hospitals in Gorgan, Iran, from May to Oct 2023. The data including used disinfectants and microbiological examination were obtained from the infection control unit of each hospital. RESULTS: The results showed that a variety of disinfectants from intermediate to high levels were employed in accordance with the World Health Organization (WHO) protocols. The microbial result revealed that 31.6% (286 out of 906) of the sample had at least one microorganism. Among identified organisms, Bacillus spp. were the predominant species followed by Staphylococcus epidermis, fungus genera, Enterobacter spp., Enterococcus spp., Pseudomonas spp., Escherichia coli, Alcaligenes spp., Staphylococcus aureus, Citrobacter spp., Corynebacterium spp., Klebsiella spp., Acinetobacter spp., Micrococcus spp., Staphylococcus saprophyticus, and Serratias spp. The highest prevalence rates of microorganisms were observed in the wards of ICU, emergency, internal medicine, and women's ward. The chi-square test revealed a significant relationship between the presence of organisms and hospital wards (P < 0.05). CONCLUSION: The presence of pathogens indicates a defect in the disinfection process, probably due to both little attention to disinfection protocols and multidrug resistance. It is not yet possible to eliminate pathogens from the hospital environment, but it can be minimized by education intervention, standardizing disinfecting processes, and monitoring by the infection control committee.

Detection and quantification by molecular techniques of early infection by Lawsonia intracellularis in suckling piglets.

BACKGROUND: Lawsonia intracellularis is the causative agent of Porcine Proliferative Enteropathy (PPE), one of the most prevalent pig enteric diseases worldwide, but with sparse information about early infections in suckling piglets in the epidemiology of PPE. With that aim, this study evaluates the prevalence of L. intracellularis in 3-week-old piglets by analysing ileal digesta content and mucosal scrapings from 383 pigs from 16 farms (aprox., 25 pigs/batch) by real-time qPCR and droplet digital PCR (ddPCR). RESULTS: Forty-nine samples yielded a qPCR positive result. Eleven samples from eight farms were confirmed as positive with concentrations of L. intracellularis from 3.5 log10 to 4.5 log10 bacteria/g of sample. Another 16 samples, eight farms, were classified as low positive (2.07-2.38 log10 bacteria/g) and 22 provided an uncertain result. Finally, 334 samples tested negative for L. intracellularis. At batch level, half of the farms included in the study had at least one positive sample and in 10 farms (62.5%) there was at least one low positive sample. The ddPCR was run in 50 of the 383 samples based on their PCR output (including low positive, uncertain and negative samples). Correlation analyses revealed a strong association between qPCR and the ddPCR results (ρ = 0.75; p < 0.001). The ddPCR allowed us to detect and confirm a positive result in the 19 samples classified as uncertain by the qPCR and detect L. intracellularis in 8 of 15 negatives by qPCR. CONCLUSIONS: The results of the study demonstrate that a number of piglets are already infected with L. intracellularis during the suckling period evidencing early infection in certain animals, adding information of PPE epidemiology and opening new research topics such as sow-piglet transmission. Study results also evidence the usefulness of a combination of qPCR and ddPCR to improve qPCR sensitivity but assuring high specificity.

Molecular epidemiology of extended-spectrum beta-lactamase-producing-Klebsiella species in East Tennessee dairy cattle farms.

Introduction: The rising prevalence of Extended-Spectrum Beta-Lactamase (ESBL)-producing Klebsiella species (spp.) poses a significant threat to human and animal health and environmental safety. To address this pressing issue, a comprehensive study was undertaken to elucidate the burden and dissemination mechanisms of ESBL-Klebsiella spp. in dairy cattle farms. Methods: Fifty-seven Klebsiella species were isolated on CHROMagar™ ESBL plates and confirmed with MADLI-TOF MS and whole genome sequenced from 14 dairy farms. Results and discussion: Six families of beta-lactamase (bla) (bla CTX-M, bla SHV, bla TEM, bla OXY, bla OXA, and bla SED) were detected in ESBL-Klebsiella spp. genomes. Most (73%) of isolates had the first three types of beta-lactamase genes, with bla SHV being the most frequent, followed by bla CTX-M. Most (93%) isolates harbored two or more bla genes. The isolates were genotypically MDR, with 26 distinct types of antibiotic resistance genes (ARGs) and point mutations in gyrA, gyrB, and parC genes. The genomes also harbored 22 different plasmid replicon types, including three novel IncFII. The IncFII and Col440I plasmids were the most frequent and were associated with bla CTXM-27 and qnrB19 genes, respectively. Eighteen distinct sequence types (STs), including eight isolates with novel STs of K. pneumoniae, were detected. The most frequently occurring STs were ST353 (n = 8), ST469 (n = 6), and the novel ST7501 (n = 6). Clusters of ESBL-Klebsiella strains with identical STs, plasmids, and ARGs were detected in multiple farms, suggesting possible clonal expansion. The same ESBL variant was linked to identical plasmids in different Klebsiella STs in some farms, suggesting horizontal spread of the resistance gene. The high burden and dual spread mechanism of ESBL genes in Klebsiella species, combined with the emergence of novel sequence types, could swiftly increase the prevalence of ESBL-Klebsiella spp., posing significant risks to human, animal, and environmental health. Immediate action is needed to implement rigorous surveillance and control measures to mitigate this risk.

Hepatitis B virus in oocytes and embryos: pregnancy outcomes and children's health.

Objective: To investigate whether the presence of hepatitis B virus (HBV) in oocytes and embryos affects pregnancy outcomes for in vitro fertilization and embryo transfer (ET) as well as is related to the vertical transmission of HBV to children. Design: Retrospective cohort study. Setting: A university-affiliated fertility center. Patients: This study included 167 couples with at least 1 hepatitis B surface antigen-seropositive partner. These couples underwent in vitro fertilization-ET, and the discarded oocytes and embryos had been tested for HBV. Couples with HBV-positive oocytes or embryos were categorized as the positive group, whereas those couples with HBV-negative oocytes and embryos served as the negative group. Interventions: None. Main Outcome Measures: Pregnancy outcomes and the rate of children's HBV infection. Results: The pregnancy outcomes of fresh and frozen ETs were not associated with the presence of HBV in the oocytes and embryos. Of the 106 infants born, 1 child whose mother tested positive for hepatitis B surface antigen but had negative oocytes and embryos was infected with HBV. Additionally, 26.09% of children who had been administered passive immunization and active vaccinations did not reach protective levels of anti-HBV antibodies (hepatitis B surface antibodies) and became nonresponders. The negative rate of children's hepatitis B surface antibody was associated with the presence of HBV in oocytes and embryos (odds ratio, 3.01; 95% confidence interval, 1.04-9.25). Conclusions: The presence of HBV in oocytes and embryos did not affect pregnancy outcomes or result in the vertical transmission of HBV to the offspring of HBV carriers. Follow-up is needed for HBV-vaccinated children with an HBV-infected parent. Booster vaccinations are necessary for continued protection.

Respiratory Isolation for Tuberculosis: A Historical Perspective.

Although tuberculosis is an ancient disease, recognition of its airborne route of transmission, with implications for respiratory isolation, is only relatively recent. Since the time of Hippocrates, the dogma among health practitioners was that the disease was hereditary or that it could be contracted by inhaling "miasma", or corrupted air. Consequently, isolation of patients was not routine practice, and, in fact, patients with scrofula (morbus regius, or "king's evil) sought to be cured by the "royal touch" throughout the middle ages. The sanatorium, which emerged in the mid-19th century, initially served as a place of healing, where patients could receive the appropriate diet, rest therapy, graduated exercise, and abundant fresh air. Major scientific breakthroughs, including Robert Koch's 1882 discovery of the tubercle bacillus as the disease's etiological agent and early 20th century experimental evidence that the organism could be transmitted via expectorated droplet nuclei, helped to reinforce the important public health role of sanatoria and tuberculosis hospitals in preventing disease transmission through isolation. The advent of highly efficacious and oral antitubercular regimens in the mid-20th century and the concurrent declining incidence of the disease contributed to the closure of tuberculosis sanatoria and hospitals in the US and western Europe. Over the past several decades, tuberculosis treatment in the US has been conducted in the outpatient setting under the supervision of local public health departments. Patients receiving treatment are required to remain in respiratory isolation in the home until they are deemed noninfectious based on multiple sputum samples. This historical review demonstrates that despite changing medical knowledge, drug therapies, and social conditions over time, the role of isolation remains an important topic of debate in the treatment of patients with pulmonary tuberculosis.

Assessing infectiousness and the impact of effective treatment to guide isolation recommendations for people with pulmonary tuberculosis.

Determining the extent and duration of infectiousness of individuals with pulmonary tuberculosis (TB) is critical for various aspects of TB care, including decisions regarding isolation. Studies suggest considerable heterogeneity in infectiousness of people with pulmonary TB. Pre-treatment, measures of bacillary burden including sputum smear microscopy, culture time-to-positivity, and Xpert MTB/RIF cycle threshold (Ct) value, predict the risk of transmission to contacts. Index patients with smear negative disease pose lower infectious risk than those who have smear-positive disease, and household contact infection is more likely with index patients who have lower Xpert Ct values. Newer tools that enable detection of Mycobacterium tuberculosis complex (Mtb complex) from cough aerosol sampling and face mask sampling may be better predictors of contact infection risk. Clinical factors such as cough strength and frequency, and presence of cavitation on chest imaging, may also assist with risk prediction. Post-treatment, smear and culture status are poor predictors of infectiousness. While the exact duration of infectiousness post treatment initiation remains uncertain, data from human-to-guinea pig transmission studies and clinical studies suggest effective treatment results in a rapid decline in infectiousness, irrespective of smear or culture conversion. This is largely supported by early bactericidal activity and transcriptomic studies, and cough aerosol sampling studies, although a subset of patients may have persistent cough aerosol positivity. These findings can enable a more nuanced approach to isolation decision making, while further research studies are awaited.

Picometer-Level In Situ Manipulation of Ferroelectric Polarization in Van der Waals layered InSe.

Ferroelectric 2D van der Waals (vdW) layered materials are attracting increasing attention due to their potential applications in next-generation nanoelectronics and in-memory computing with polarization-dependent functionalities. Despite the critical role of polarization in governing ferroelectricity behaviors, its origin and relation with local structures in 2D vdW layered materials have not been fully elucidated so far. Here, intralayer sliding of approximately six degrees within each quadruple-layer of the prototype 2D vdW ferroelectrics InSe is directly observed and manipulated using sub-angstrom resolution imaging and in situ biasing in an aberration-corrected scanning transmission electron microscope. The in situ electric manipulation further indicates that the reversal of intralayer sliding can be achieved by altering the electric field direction. Density functional theory calculations reveal that the reversible picometer-level intralayer sliding is responsible for switchable out-of-plane polarization. The observation and manipulation of intralayer sliding demonstrate the structural origin of ferroelectricity in InSe and establish a dynamic structural variation model for future investigations on more 2D ferroelectric materials.

Radiation shielding transmission data for modern digital radiography.

BACKGROUND: Radiography is one of the most widely used x-ray imaging modalities. In National Council on Radiation Protection and Measurements (NCRP) Report No. 147, transmission data for radiographic systems were evaluated on those installed before 2000. For x-ray systems (except intraoral dental) manufactured on or after June 10, 2006, the U.S. required minimum half-value layer (HVL) was increased; for example, 2.9 (2.3) mm Al at 80 kV, where the value in parenthesis denotes the earlier requirement before the above date. PURPOSE: To calculate the transmission of the broad x-ray beam of modern digital radiography (DR) through shielding materials. METHODS: X-ray beam HVLs on two DR systems (Agfa DR 600, GE Revolution XR/d) were measured in 10 kV increments between 60 and 120 kV, with a calibrated ionization chamber (Radcal model 10 × 5-60) and varying thickness of aluminum 1100 plates. Monte Carlo (Geant4) simulation was performed to calculate the transmission of broad x-ray beams through lead, concrete, gypsum, and steel, with x-ray HVLs matching those of the DR 600 at two beam filtrations (default, 1 mm Al plus 0.1 mm Cu added filtration). The transmission data were fitted to the Archer equation. RESULTS: HVLs on two DR systems with default beam filtration were consistent (median difference, 2.1%; maximum difference, 5.5%). An additional beam filtration option (1 mm Al plus 0.1 mm Cu) on the DR 600 substantially increased HVLs by 45.2%-61.2%. Transmission fitting parameters were provided for seven tube voltages (60-120 kV) at two beam filtrations. CONCLUSION: This work presents transmission data for modern DR systems, indicating increased x-ray beam filtration compared to the primary x-ray beam in NCRP Report No. 147. The updated transmission data can enhance structural shielding evaluations at individual tube voltages or with a workload distribution.