Journals
2026 EN
Sharma Yogita · Bhat Deepa · Sridevi Parikipandla
+6 more
ABSTRACT Background Sickle cell disease (SCD) poses major reproductive health challenges for women. Evidence on pregnancy and maternal outcomes among women with SCD remains sparse from India. This study examined reproductive health, pregnancy‐related complications, and outcomes among women with SCD compared with age‐ and occupation‐matched controls. Methods A community‐based retrospective cross‐sectional study was conducted among women of reproductive age in five SCD‐endemic tribal areas of India. Data were collected through structured interviews covering pregnancy history, hydroxyurea use during the periconceptional‐to‐antenatal period, delivery, and postpartum outcomes. Of a cohort of 108 women with SCD, data of 37 ever‐married women with SCD with a history of conceptions and their matched controls were used. Results Women with SCD showed higher rates of anaemia (43% vs. 12.5%, p < 0.001), pain crises (42% vs. 11.5%, p < 0.001), and blood transfusion during pregnancy (16% vs. 1%, p < 0.001). They also had more complications during delivery, including pain, fever, and emergency caesarean sections (10% vs. 3%, p < 0.05). Postpartum complications such as pain, vaso‐occlusive crises, and ICU admissions were more frequent among SCD women. Birth preparedness was notably poorer. The proportion of live births to total conceptions was slightly lower among women with SCD (82% vs. 87%) due to a higher number of abortions and stillbirths. Only 10% of women with SCD used hydroxyurea during the periconceptional‐to‐antenatal period. Conclusion Women with SCD in tribal settings face considerable reproductive and maternal health risks. Integrating reproductive health and antenatal services into SCD care is essential to reduce maternal and neonatal morbidity in high‐burden, resource‐limited regions.
Journals
2026 EN
Chrenková Adriana · Nashier Payal · Madsen Cecilie L.
+7 more
HipA‐like kinases are widespread bacterial serine–threonine kinases, yet their regulatory mechanisms remain poorly understood. Here, we characterise two novel HipA‐like systems, the monocistronic hipL and bicistronic hipIN , also encoding HipS‐like and HIRAN domains. We show that the hipL gene contains an internal translation initiation site producing a smaller variant, HipL S , which counteracts HipL‐mediated toxicity via its HipS‐like domain. Contrary to this, HipN requires both the HipS‐like and the HIRAN domains to neutralise HipI‐mediated toxicity. Neither system forms stable toxin–antitoxin (TA) complexes in vitro , distinguishing them from classical type II systems. Finally, we show that autophosphorylation affects HipL but not HipI‐mediated toxicity. These findings reveal diverse regulatory architectures in HipA‐like TA systems, shaped by domain composition and operon structure.Impact statement Kinases are increasingly recognised as key regulators in bacteria. Here, we show how complex operon and domain structures can contribute to kinase function and regulation, revealing increasingly complex regulatory networks in microbes.
Journals
2026 EN
Agarwal Devanshi · Neal Sonya E.
Parenthood has been linked to lower retention of women in academia, yet the specific challenges faced by mothers remain underexplored. We interviewed nine mothers across different career stages in the life sciences to qualitatively examine how motherhood intersects with academic milestones. Participants described challenges unique to academia, including dependence on supervisors, publication pressure, financial strain, and limited awareness of available institutional resources. They also shared strategies that supported their success, such as transparent communication with supervisors, designating student–parent coordinators, and creating peer communities for mothers in academia. By highlighting shared barriers and effective solutions, this work underscores the need for structural and cultural reforms to better support mothers in academia and retain talented scientists in STEM fields.
Journals
2026 EN
Kay Holly · Jabbur Maria Luísa
Circadian clocks are endogenous timekeeping mechanisms that are phylogenetically widespread. Despite the immense diversity of bacterial life, to date, clocks have been identified in few bacterial species. The cyanobacterial clock is understood in great detail, and the roles of its clock proteins in other types of timing mechanisms and in stress resistance are being studied in an ever‐growing range of species. Studies of host‐associated microbiomes have shown that host and microbial rhythmicity impact one another reciprocally. However, bacterial rhythms have primarily been studied in species in isolation or in host‐associated microbiomes. Here, we summarize the state of the field of microbial chronobiology and propose the hypothesis that rhythmicity could be an emergent property of microbial interactions in free‐living bacterial communities.
Journals
2026 EN
Qi Xi · Liu Kai · Zhang Yiming
+10 more
Abstract Background Neoadjuvant chemoradiotherapy for locally advanced rectal cancer yields pathological complete response rates of only 10%–20%. Dose‐escalation strategies may improve outcomes, but optimal GTV‐to‐PGTV margins for CT‐guided radiotherapy with daily IGRT remain undefined. Methods Twelve LARC patients undergoing CT‐guided daily IGRT with a simultaneous integrated boost were included. Daily diagnostic‐quality fan‐beam CT (FBCT) scans were acquired for IGRT. GTV and CTV were delineated on planning CT and all FBCTs. Target coverage margins were assessed by isotropically expanding the planning GTV until more than 95% of the voxels of the sequential GTVs were covered. A margin with a coverage probability threshold of 90% was defined as adequate. An independent validation cohort of 30 patients who underwent weekly FBCT‐guided image guidance was further analyzed. Overlap volumes between PGTVs and organs‐at‐risk (OARs; bladder and small bowel) were calculated to assess OAR sparing. Results Analysis of 286 FBCT scans showed that a 6 mm isotropic GTV‐to‐PGTV margin achieved>95% coverage in>90% of fractions. Compared with 10 mm expansion, a 6 mm PGTV reduced the overlap volumes with the bladder and small bowel by 68.5% and 68.4%, respectively. A 6 mm isotropic expansion achieved>95% coverage in 91.3% of fractions in the validation cohort. Conclusion A 6 mm isotropic GTV to PGTV margin provides adequate target coverage for most middle‐ and lower‐rectal tumors while reducing OAR overlap. This finding could facilitate safer dose escalation while maintaining target coverage. However, larger margins may be necessary for smaller tumors or those located in the high rectum.
Journals
2026 EN
Jones A. Kyle
Abstract Background Radiation protection in the operating room (OR) environment is a subject of much discussion in both the surgery and medical physics communities. Radiation exposure is often infrequent during image‐guided procedures, especially when only 3D imaging for navigation is used. This is accompanied by unique personnel considerations, including staff that rotate in and out of the OR and staff that are scrubbed in and do not have the opportunity to easily don and doff radioprotective garments. These communities seek clear guidance about the magnitude of stray radiation dose in the OR environment. However, prior studies have reported conflicting data on the topic and have used different methods and instruments. Purpose To systematically measure the magnitude of stray radiation doses in a simulated OR environment in locations relevant to the placement of personnel during image‐guided spine surgery and to make recommendations for radiation protection based on these data when using a mobile cone beam computed tomography (CBCT) system and a realistic anthropomorphic phantom on an actual spine surgery table. Methods Measurements of stray radiation dose were performed in a grid pattern in a simulated OR environment using pressurized ionization chamber survey meters and two configurations of a tissue‐mimicking anthropomorphic phantom, large (L) and extra‐large (XL). The phantom was imaged using “navigation” mode (i.e., CBCT) with standard and high definition (HD) protocols. Stray radiation dose was measured at heights corresponding to chest level (125 cm) and eye level (175 cm) of a typical operator and additional heights of 100 and 150 cm. Results The absolute per scan whole body dose in the shadow of the gantry console 2 m from isocenter at a height of 125 cm (chest level) was 1.26 µSv for an equal mix of L and XL patients, and at a height of 175 cm (eye lens level) the air kerma was 9.22 µGy. The dose at 2 m from isocenter on the head side of the patient at a height of 125 cm was 7.93 µSv and air kerma at a height of 175 cm was 14.7 µGy. Doses at the same distance from isocenter and same heights on the side of the gantry opposite the console were 13.5 µSv and 15.0 µGy. Conclusions Stray radiation doses were lowest in the shadow of the gantry console and were higher at a height of 175 cm compared to a height of 125 cm. Based on measured stray radiation doses at a distance of 2 m from isocenter, multiple radiation protection strategies can be employed to maintain occupational doses as low as reasonably achievable for operating room personnel.
Journals
2026 EN
Ferrer Carlos · Huertas Concepción · Feijoo Marcos
+2 more
Abstract Background Plastic scintillation detectors (PSD) are widely used for detecting and measuring ionizing radiation. These detectors are versatile, with high efficiency, fast response and the ability to provide real‐time measurements. Purpose Evaluate the suitability of Blue Physics PSD (BP‐PSD) for performing ultra‐fast dosimetric commissioning measurements with high accuracy and precision in a very short time. Methods Ultra‐fast measurements were performed in water using a BP‐PSD on an Elekta Unity MR‐linac. Percentage depth doses (PDD) and profiles at different depths were measured at two movement velocities, 10 mm/s and 20 mm/s, for field sizes ranging from 10 × 10 cm 2 to 1 × 1 cm 2 . Gamma analysis was conducted to compare these measurements with those obtained during machine commissioning using a PTW Semiflex 3D ionization chamber (for PDD) and a PTW micro‐Diamond detector (for PDD and profiles). Gamma criteria of 2%/2 mm and 1%/1 mm dose difference/distance to agreement were studied, alongside field size, penumbra, and measurement time. Results All PDD and profile gamma passing rates were 100% at 2%/2 mm. At the stricter 1%/1 mm criteria, all PDD showed a passing rate above 96.97% for both velocities, with most of the profiles exceeding 95% at 10 mm/s and 90% at 20 mm/s. Gamma analysis results were superior for smaller fields (1 × 1 cm 2 and 2 × 2 cm 2 ) and generally better at 10 mm/s. On average, the penumbra measurements obtained with the PSD were greater than those achieved with the micro‐Diamond detector. Measurement times were found to be between 7 and 14 times shorter for PDD, and between 5 and 9 times shorter for profiles at speeds of 10 mm/s and 20 mm/s, respectively. Conclusions Ultra‐fast measurements using the Blue Physics PSD are suitable for acquiring dosimetric commissioning data with high accuracy and precision, and can be performed in a much shorter timeframe than with commonly used detectors.
Journals
2026 EN
Alhussan Abdulaziz · Crilly Richard
Abstract Purpose This study evaluates the dosimetric impact of integrating thin metallic scatter foils with Cerrobend contact skin collimators to improve dose uniformity, conformality, and distal tissue sparing in small superficial electron fields. Materials and methods Electron beams of 8, 12, and 15 MeV from an Elekta Versa HD LINAC were delivered through a Cerrobend skin collimator with a 2.0 cm aperture at 100.0 cm SSD. Thin aluminum (Al) and lead (Pb) foils (< 2.50 mm) were placed on the collimator. Gafchromic EBT3 film in a solid‐water phantom was used to measure depth‐dose distributions and isodose profiles following TG‐235–consistent calibration. Results Scatter foils produced thickness‐ and Z‐dependent modulation of beam characteristics. At 8 MeV, the thickest Pb foil (1.07 mm) reduced the practical range ( R p ) by ∼45% and shifted D m a x proximally by ∼0.5 cm, yielding substantial distal tissue sparing. Al foils caused smaller R p reductions (15%–25%) but improved lateral dose uniformity, producing smoother and more symmetric isodose contours. The 90% isodose diameter decreased with foil thickness for both materials, with Pb showing the largest contraction (∼20%–25%, energy‐dependent), enhancing field conformality. Penumbra width increased slightly for thin foils but stabilized or narrowed for larger thicknesses. These effects diminished at 15 MeV, indicating reduced sensitivity of high‐energy electrons to thin‐foil perturbation. Conclusions Thin metallic foils placed on Cerrobend skin collimators enable a controllable balance between dose uniformity (improved with Al) and conformality with distal sparing (enhanced with Pb). This simple, LINAC‐independent configuration offers a cost‐effective method for modulating small‐field electron beam characteristics and may serve as a practical adjunct for treating superficial lesions.
Journals
2026 EN
Khalifa Mateb Al · Ma Tianjun · Aljuaid Haya
+2 more
Abstract Purpose This study describes and evaluates the acceptance procedure for a ViewRay (VR) MRIdian 0.35T MR‐Linac, emphasizing key challenges, limitations, and recommendations to enhance clinical performance and accuracy. Methods A comprehensive acceptance test was conducted at a single institution, following the manufacturer's protocols and aligned with established acceptance guidelines. Specific tools and phantoms were used to assess three primary components: mechanical, dosimetric, and Magnetic Resonance Imaging (MRI). Results Overall, the test outcomes satisfied the manufacturer's specifications. However, certain issues were identified: high couch attenuation at specific gantry angles (leading to their exclusion from treatment), variations in magnetic field homogeneity at different gantry angles, and discrepancies between TPS calculations and measurements for field output factors smaller than 0.83 cm × 0.83 cm. Conclusion This work provides a detailed account of the acceptance testing procedure and establishes a QA baseline for 0.35T MR‐Linac systems. In doing so, it also identifies key system limitations, such as couch attenuation, magnetic field inhomogeneity, and small‐field output discrepancies, underscoring the need for careful gantry angle selection, field homogeneity optimization, and meticulous validation of very small fields.
Journals
2026 EN
Nomura Yusuke · Tanaka Sodai · Takei Hideyuki
+10 more
Abstract Purpose This study quantified inter‐ and intra‐fractional setup accuracies in the upright posture and compared them among setups with different immobilization methods. Methods Two and four setups were examined for abdominal and head and neck (HN) cancer treatments, respectively. Fifteen asymptomatic volunteers were positioned to a replicated chair of an upright radiotherapy platform with leg immobilization devices, backrest attachments, thermoplastic masks, and vacuum cushions. The 3D positions of the subject body and masks were monitored by calculating 3D point clouds of 26 surface markers from three camera images. The inter‐fractional setup errors were calculated by repeating the same setup five times. The intra‐fractional displacements were evaluated while the subjects remained in the setups for 20 min. These setup errors and displacements were compared among the setups with different immobilization methods. The intra‐fractional displacements were also compared between this study and previous studies in the supine posture. Results Inter‐fractional setup errors in the abdominal setups were reduced from 6.6 ± 3.3 to 3.9 ± 1.7 mm by using the masks. The HN setup using both the leg immobilization devices and backrest attachments had the setup errors of 2.9 ± 1.7 mm. This was smaller than the setup errors observed in three other HN setups that did not use either or both of the devices together. Intra‐fractional displacements of these abdominal and HN setups with the immobilization devices were 1.9 ± 1.1 and 1.8 ± 1.5 mm, respectively, which were smaller than those in the other setups. These displacements were equivalent to those in the previous studies. Conclusions Utilizing the masks increased upright setup accuracy in the abdominal setup. The leg immobilization devices and backrest attachments provided the highest setup accuracy in the upright HN setup. These findings will be useful to expand the applicability of upright radiotherapy for various cancer treatments.