Dual Energy Research Articles

Enhancing thermodynamic performance with an advanced combined power and refrigeration cycle with dual LNG cold energy utilization

Utilizing waste heat to drive thermodynamic systems is imperative for improving energy efficiency, thereby improving sustainability. A combined cooling and power systems (CCP) utilizes heat from a temperature source to deliver both power and cooling. However, CCP systems utilizing LNG cold energy suffers from low second law efficiency due to significant temperature differences. To address this, an “Advanced Power and Cooling with LNG Utilization (ACPLU)” system is proposed, integrating a cascaded transcritical carbon dioxide (TCO2)-LNG cycle with an Organic Rankine cycle (ORC) for improved power generation and an absorption refrigeration system (ARS) for simultaneous cooling. This study evaluates the second law efficiency, net work output, and exergy destruction performance through a sensitivity analysis, optimizing variables such as heat source temperature, superheater temperature difference, ORC and CO2 turbine inlet and condenser pressures, evaporator temperature, and pinch point temperatures of heat exchangers and generator. Compared to previous studies on CCP systems, the ACPLU shows a superior performance, with a second law efficiency of 27.3 % and a net work output of 11.76 MW. Cyclopentane as an ORC working fluid resulted in the highest second law efficiency of 29.06 % and net work output of 12.27 MW. Parametric analysis suggested that heat source temperature significantly impacts net power output. The exergy analysis concluded that a high-pressure ratio and good thermal match between the heat exchangers enhance overall performance. Utilizing artificial neural network (ANN) to produce a multiple-input-multiple-output (MIMO) objective function and performing multi-objective optimization (MOO) using genetic algorithm (GA), an improved second law efficiency and net power output by 28.11 % and 14.16 MW respectively, with pentane as the working fluid, is demonstrated. An average cost rate of 9.121 $/GJ was observed through a thermo-economic analysis. The ACPLU system is promising for medium temperature waste heat recovery, such as, pharmaceutical manufacturing plants.

Design and Development of an Unmanned/Autonomous Ocean Surface Vehicle using Self-Sustaining Dual Renewable Energy Harvesting System

Design and Development of an Unmanned/Autonomous Ocean Surface Vehicle using Self-Sustaining Dual Renewable Energy Harvesting System

Identifying Risk Factors for Presarcopenia in Early Middle Age

ObjectiveThis study aimed to determine whether risk factors for presarcopenia can be identified in a sample of early middle-aged men and women. DesignProspective study. SettingLongitudinal data from the Dunedin Multidisciplinary Health and Development Study were used to investigate the relationship between presarcopenia at age 45 years and selected early markers at ages 26, 32, and 38 years. ParticipantsLongitudinal data from N=899 participants from the Dunedin Multidisciplinary Health and Development Study. InterventionsNot applicable. Main Outcome MeasuresPresarcopenia was defined as low relative appendicular lean mass index assessed by dual energy x-ray absorptiometry and low strength assessed by grip strength. Logistic regressions were used to describe the association between selected markers and presarcopenia at age 45 years. ResultsMultivariate logistic regression revealed that a higher body mass index (BMI) at ages 26, 32, and 38 years was associated with lower likelihood of presarcopenia at age 45 years in both men and women (odds ratio [OR] range, 0.46-0.64). Higher age-normative grip strength at age 38 years in both men and women (OR range, 0.88-0.92) was also associated with lower likelihood for presarcopenia. Lastly, lower self-perceived physical fitness level in men at age 38 years was associated with an increased likelihood of presarcopenia at age 45 years (OR, 9.35; 95% confidence interval, 3.28-26.70). ConclusionsBMI and strength were associated with lower likelihood of presarcopenia during middle age. A higher likelihood of presarcopenia was associated with sex-specific lower self-perceived physical fitness. These modifiable biomarkers may serve as targets for clinical screening and early intervention aimed at slowing or preventing progression to sarcopenia in old age.

Bone health in childhood low-grade glioma: an understudied problem.

Children with a supratentorial midline low-grade glioma (LGG) may be at risk for impaired bone health due to hypothalamic-pituitary dysfunction, obesity, exposure to multiple treatment modalities, and/or decreased mobility. The presence of impaired bone health and/or its severity in this population has been understudied. We aimed to identify the prevalence and risk factors for bone problems in children with supratentorial midline LGG. A retrospective study was performed in children with supratentorial midline (suprasellar or thalamic) LGG between 1 January 2003 and 1 January 2022, visiting the Princess Máxima Center for Pediatric Oncology. Impaired bone health was defined as the presence of vertebral fractures and/or very low bone mineral density (BMD). In total, 161 children were included, with a median age at tumor diagnosis of 4.7 years (range: 0.1-17.9) and a median follow-up of 6.1 years (range: 0.1-19.9). Five patients (3.1%) had vertebral fractures. In 99 patients, BMD was assessed either by Dual Energy X-ray Absorptiometry (n = 12) or Bone Health Index (n = 95); 34 patients (34.3%) had a low BMD (≤ -2.0). Impaired visual capacity was associated with bone problems in multivariable analysis (OR: 6.63, 95% CI: 1.83-24.00, P = 0.004). In this retrospective evaluation, decreased BMD was prevalent in 34.3% of children with supratentorial midline LGG. For the risk of developing bone problems, visual capacity seems highly relevant. Surveillance of bone health must be an aspect of awareness in the care and follow-up of children with a supratentorial midline LGG. Patients with supratentorial midline LGG may encounter various risk factors for impaired bone health. Bone problems in survivors of childhood supratentorial midline LGG are, however, understudied. This is the first paper to address the prevalence of bone problems in this specific patient population, revealing visual problems as an important risk factor. Diencephalic syndrome historyand/or weight problems associated with hypothalamic dysfunction were related to bone problems in univariate analyses. The results of this study can be used in the development of guidelines to adequately screen and treat these patients to subsequently minimizing bone problems as one of the endocrine complications.

Changing Australia's trading language has enhanced the implementation of objective carcase measurement technologies.

In 2016 an Australian project, the Advanced Livestock Measurement Technologies project (ALMTech), was initiated to accelerate the development and implementation of technologies that measure lean meat yield and eating quality. This led to the commercial testing, and implementation of a range of new technologies in the lamb, beef, and pork industries. For measuring lean meat yield %, these technologies included dual energy X-ray absorptiometry, hand-held microwave systems, and 3-D imaging systems. For measuring beef rib-eye traits and intramuscular fat %, both pre- and post-chilling technologies were developed. Post-chilling, a range of camera systems and near infrared spectrophotometers were developed. While pre-chilling, technologies included insertable needle probes, nuclear magnetic resonance, and X-ray systems. Initially these technologies were trained to predict the pre-existing traits already traded upon within industry. However, this approach was limiting because the technologies could measure attributes that were either non-existent in the trading language, were superior as calibrating standards, or more accurately reflected value than the pre-existing trait. Therefore, we introduced IMF% into the trading language for both beef and sheep meat, and carcase lean%, fat%, and bone% for sheep meat. These new technologies and the traits that they predict have delivered multiple benefits. Technology provider-companies are instilled with the confidence to commercialise due to the provision of achievable accreditation standards. Processors have the confidence to invest in these technologies and establish payment grids based upon their measurements. And lastly, it has enhanced data flow into genetic databases, industry data systems (MSA), and as feedback to producers.

What is the best predictor of body fat percentage for older brazilian women?

This study aimed to investigate the validity of several equations and predictive indices for estimating body fat percentage (%BF) in 152 older women, with an average age of 67.4 years and an average body mass index (BMI) of 28.65 kg/m². To this end, anthropometric measurements including height, body weight, circumferences (waist and hip), and a dual energy X-ray absorptiometry (DXA) scan were performed. All measurements were performed by trained researchers following specific protocols. The results were compared to the dual energy X-ray absorptiometry (DXA) technique, which is considered the reference method. The analyzed equations showed moderate to good correlation coefficients with DXA, with particular emphasis on Visser’s equation 6, which showed the best correlation (r = 0.752, p < 0.001). However, the agreement between the equations and DXA, as assessed by the Lin concordance coefficient, was classified as poor (ρc < 0.90). This indicates that although the equations have a positive correlation with body composition, they tend to deviate from the identity line when compared to the reference method. Additionally, the equations showed high sensitivity for detecting obesity when the cut-off point of 30% body fat was adopted, indicating a good ability to identify the presence of the condition. However, the equations, with the exception of equation 4, showed low specificity, meaning they had limited ability to detect normal individuals, resulting in a low negative predictive value. The results suggest that BF% equations and indices are dependent on the populations in which they were developed. The specificity and sensitivity of these equations may vary, and it is important to carefully select the most appropriate equation for estimating BF% in older Brazilian women. Keywords: Anthropometry; body composition; older adults.

Dual layer energy management model for optimal operation of a community based microgrid considering electric vehicle penetration

This work develops a dual-layer energy management (DLEM) model for a microgrid (MG) consisting of a community, distributed energy resources (DERs), and a grid. It ensures the participation of all these energy entities of MG in the market and their interaction with each other. The first layer performs the scheduling operation of the community with the goal of minimizing its net-billing cost and sends the obtained schedule to the DER operator and grid. Further, the second layer formulates a power scheduling algorithm (PSA) to minimize the net-operating cost of DERs and takes into account the load demand requested by the community operator (COR). This PSA aims to achieve optimal operation of MG by considering solar PV power, requested demand, per unit grid energy prices, and state of charge of the battery energy storage system of the DER layer. Moreover, to study the impact of electric vehicles (EVs) load programs on DLEM, the advanced probabilistic EV load profile model is developed considering practical and uncertain events. The EV load is modelled for grid to vehicle mode, and a new mode of EV operation is introduced, i.e., vehicle to grid with EV demand response strategy (V2G_DRS) mode. The solar PV and load demand data are obtained from the MG setup installed and buildings present at the university campus. However, a scenario reduction technique is used to deal with the uncertainties of the obtained data. In order to evaluate the efficacy of the developed DLEM, its results are compared to previously reported energy management models. The results reveal that DLEM is superior to the existing models as it decreases the net-billing cost of COR by 13% and increases the profit of the DER operator by 17%. Further, it is found that for the highest EV penetration, i.e., 30 EVs, the V2G_DRS mode of EV operation reduces the total energy imported by COR by 11.39% and the net-billing cost of COR by 7.88%. Therefore, it can be concluded that the proposed model with the introduced V2G_DRS mode of EV makes the operation of all the entities of MG more economical and sustainable.

Triple-Combination Nanoregulator Based on Dual Energy Inhibition Strategy Induction Reshape Tumor Microenvironment for Amplified Starvation/Gas/Photothermal Therapy

Triple-Combination Nanoregulator Based on Dual Energy Inhibition Strategy Induction Reshape Tumor Microenvironment for Amplified Starvation/Gas/Photothermal Therapy

Variations in bioelectrical impedance devices impact raw measures comparisons and subsequent prediction of body composition using recommended estimation equations

Background & AimsBioelectrical impedance analysis (BIA) for body composition estimation is increasingly used in clinical and field settings to guide nutrition and training programs. Due to variations among BIA devices and the proprietary prediction equations used, studies have recommended the use of raw measures of resistance (R) and reactance (Xc) within population-specific equations to predict body composition. ObjectiveWe compared raw measures from three BIA devices to assess inter-device variation and the impact of differences on body composition estimations. MethodsRaw R, Xc, impedance (Z) parameters were measured on a calibrated phantom and athletes using tetrapolar supine (BIASUP4), octapolar supine (BIASUP8), and octapolar standing (BIASTA8) devices. Measures of R and Xc were compared across devices and graphed using BIA vector analysis (BIVA) and raw parameters were entered into recommended athlete-specific equations for predicting fat-free mass (FFM) and appendicular lean soft tissue (ALST). Whole-body FFM and regional ALST were compared across devices and to a criterion five-compartment (5C) model and dual energy X-ray absorptiometry for ALST. ResultsData from 73 (23.2 ± 4.8y) athletes were included in the analyses. Technical differences were observed between Z (range 12.2 - 50.1Ω) measures on the calibrated phantom. Differences in whole-body impedance were apparent due to posture (technological) and electrode placement (biological) factors. This resulted in raw measures for all three devices showing greater dehydration on BIVA compared to published norms for athletes using a separate BIA device. Compared to the 5C FFM, significant differences (p < 0.05) were observed on all three equations for BIASUP8 and BIASTA8, with constant error (CE) from -2.7 to -4.6 kg; no difference was observed for BIASUP4 or when device-specific algorithms were used. Published equations resulted in differences as large as 8.8 kg FFM among BIA devices. For ALST, even after a correction in the error of the published empirical equations, all three devices showed significant (p<0.01) CE from -1.6 to -2.9 kg. ConclusionsRaw bioimpedance measurements differ among devices due to technical, technological, and biological factors, limiting interchangeability of data across BIA systems. Professionals should be aware of these factors when purchasing systems, comparing data to published reference ranges, or when applying published empirical body composition prediction equations

One-year changes in body composition and musculoskeletal health following metabolic/bariatric surgery.

There are limited comparative studies between one anastomosis gastric bypass (OAGB) versus Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) on body composition and musculoskeletal health. To compare changes in body composition, areal bone mineral density (aBMD), muscle strength, and physical function in the first year following OAGB, RYGB and SG within a UK-based healthcare setting. This is a secondary analysis of the BARI-LIFESTYLE trial in 119 adults (77% women; mean±SD, age: 45.9±10.3 years; BMI: 43.6±5.5 kg/m2) who underwent OAGB (n=19), RYGB (n=39) and SG (n=61). Body composition and aBMD by dual energy x-ray absorptiometry, handgrip strength, sit-to-stand (STS) test and 6-minute walking test (6MWT) were assessed pre-surgery and at 12 months post-surgery. OAGB, RYGB, and SG exhibited similar reductions in body weight, body fat and lean mass (within-group comparisons, p<0.001). All surgery types were associated with reductions in aBMD at the total hip, femoral neck, and lumbar spine, which were more pronounced after OAGB and RYGB compared to SG (all p<0.03), though no difference between OAGB and RYGB. Despite reductions in absolute handgrip strength, relative handgrip strength, STS test and 6MWT improved post-surgery (all p<0.02), with no differences by surgical procedure. OAGB, RYGB, and SG resulted in comparable weight loss, changes in body composition and improvements in relative muscle strength and physical function. OAGB and RYGB, compared with SG, led to greater BMD reductions at clinically relevant sites. Future long-term studies should explore whether these BMD reductions translate into a greater fracture risk.

Mathematical modeling of radiation transparencies in the countable implementation of the dual energy method based on analog amplitude analysis of original signals

A mathematical model of radiation transparency in the computational implementation of the dual energy method based on analog discrimination of the original signals is given. The generalized mathematical model of radiation transparency in the analyzed implementation of the dual energy method is based on the analog separation of the initial electrical signals from the X-ray detector by amplitude into low-energy and high-energy signals with subsequent counting of these signals. Analog separation of the output signals of the X-ray detector by amplitude is carried out using a two-channel amplitude analyzer. The proposed model takes into account the maximum energy of X-ray photons, the energy threshold for separating signals into low-energy and high-energy signals, materials and sizes of radiation-sensitive detector elements, and parameters of control objects. The model can be used to conduct research on the influence of noise caused by the quantum nature of X-ray radiation on the quality of identification of the attenuating material, for example, by effective atomic number, in relation to the considered implementation of the dual energy method, as well as for a reasonable choice of parameters of the corresponding dual-energy digital radiography systems and X-ray computed tomography.

Comparison of automated kidney stone size measurement and volumetry in photon counting CT compared to 3rd generation dual energy CT and physically measurements - an ex vivo study.

This ex vivo study aimed to compare a newly developed dual-source photon-counting CT (PCCT) with a 3rd generation dual-source dual-energy CT (DECT) for the detection and measurement (stone lengths and volumetrics) of urinary stones. 143 urinary stones with a known geometry were physically measured and defined as reference values. Next, urinary stones were placed in an anthropomorphic abdomen-model and were scanned with DECT and PCCT. Images were read by two experienced examiners and automatically evaluated using a specific software. DECT and PCCT showed a high sensitivity for manual stone detection of 97.9% and 94.4%, and for automatic detection of 93.0% and 87.4%, respectively. Compared to that uric acid and xanthine stones were recognized slightly worse by DECT and PCCT with manual stone detection (93.3% and 82.2%), and with automatic detection (77.8% and 60.0%). All other stone entities were completely recognized. By comparing the maximum diameter of the reference value and DECT, Pearson-correlation was 0.96 (p < 0.001) for manual and 0.97 (p < 0.001) for automatic measurement, and for PCCT it was 0.94 (p < 0.001) for manual and 0.97 (p < 0.001) for automatic measurements. DECT and PCCT can also reliably determine volume manually and automatically with a Pearson-correlation of 0.99 (p < 0.001), respectively. Both CTs showed comparable results in stone detection, length measurement and volumetry compared to the reference values. Automatic measurement tends to underestimate the maximum diameter. DECT proved to be slightly superior in the recognition of xanthine and uric acid stones.

Load carriage does not reduce absolute mechanical power output but reduces agility in elite military police officers

Objectives. The main objective of this study was to evaluate mean propulsive velocity (MPV), mean propulsive force (MPF) and mean propulsive power (MPP) in elite police officers under LOADED and UNLOADED conditions. The study also investigated the association of body composition and strength levels under the same load conditions. Methods. Twenty-one men from an elite unit in Brazil participated in the study, performing Smith machine half squats and an agility test. Dual energy X-ray absorptiometry measured body composition; a linear encoder measured MPV, MPF and MPP during the half squats; and a manual chronometer registered agility test performance. Results. The results showed that wearing and carrying occupational loads did not alter the squat exercise’s MPP, MPV and MPF but reduced the performance of relative MPP and agility (p < 0.05). The results also showed that MPP had a higher association with force (i.e., MPF and one-repetition maximum [1RM]) than velocity (i.e., MPV and agility) under the LOADED condition (p < 0.05). Among the body composition variables, only lean body mass was associated with MPP under the LOADED condition (p < 0.05). Conclusion. These findings suggest that load carriage does not reduce absolute mechanical power output, but reduces the relative MPP and agility in military police officers.

The Nutritional Burden of Cancer: Nutritional Status and Body Composition Differences Between Children with Acute Lymphoblastic Leukemia and their Siblings in Guatemala

During treatment, children with acute lymphoblastic leukemia (ALL) gain fat mass and lose skeletal muscle mass. The great majority live in low- and middle-income countries with few studies of their body composition and none addressing the hypothesis that the disease itself contributes to nutritional morbidity. At diagnosis, children with ALL were compared to their siblings on socioeconomic status (SES). Nutritional status was assessed by mid-upper arm circumference (MUAC)-for-age Z scores and body composition by dual energy x-ray absorptiometry (DXA). Median SES scores for the patients (47.5) and their siblings (47.0) were very similar (P = 0.5). MUAC Z scores for patients aged >5 years were lower than for siblings (P < 0.001). On DXA siblings had a higher mean appendicular lean mass index Z score, a surrogate of skeletal muscle mass, than patients (P = 0.019). A logistic model to estimate the odds ratio (OR) of being severely/moderately under-nourished (classified by MUAC Z score) by SES revealed that, compared with siblings (n = 49), children with ALL (n = 60) had a higher probability of being under-nourished (OR 5.25, 95% CI 1.44–25.95, P = 0.02). The results support the hypothesis that children at diagnosis of ALL in Guatemala are more nutritionally depleted than their apparently healthy siblings.

Performance of NB-CTMFD Detector Versus Ludlum 42-49B, and Fuji NSN3 Detectors for Hard (Am-Be) and Soft (Cf-252 Fission) Energy Spectra Neutron Sources Within Lead/Concrete Shielded Configurations

Abstract This paper presents the results of neutron detection efficiency and dosimetry between a nonborated centrifugally tensioned metastable fluid detector (NB-CTMFD) configured to detect fast (&amp;gt;0.1 MeV) versus two widely used combined thermal and fast neutron detection devices of similar form factors: moderated He-3 based Ludlum-42-49BTM neutron detector, and, the Fuji NSN3TM pressurized nitrogen-methane filled neutron detector. The one-on-one performance comparisons were conducted using hard (Am-Be) and soft (Cf-252 fission) neutron spectra isotope neutron sources positioned behind various levels of lead and concrete shielding ranging in thickness from 0 cm (unshielded) to up to 30 cm. The comparisons were conducted together with Monte Carlo N-Particle (MCNP) code simulations to account for 3-D effects and to relate the detection sensitivity with the dose rate. The MCNP model results for the neutron energy spectrum were validated versus experimental measurements using the H*TMFD. While the Ludlum and NSN3 detectors operate at a fixed sensitivity setting, the NB-CTMFD detector could be operated at various sensitivity levels by varying the tensioned metastable negative pressure (Pneg) from 0.3 MPa to 0.7 MPa. The NB-CTMFD (configured for fast: &amp;gt;0.1 MeV neutron detection at Pneg = 0.7 MPa) offered relative sensitivity enhancements of up to 15x greater than the Ludlum and ∼5x greater than the NSN3 detector for low shielding thicknesses. For larger thicknesses, the advantage factor for NB-CTMFD unit reduces with increased fast neutron removal via down-scattering, which benefits the Ludlum and NSN3 detectors. Our companion paper compares performance with a Cf-252 spectrum using a borated CTMFD (covering dual energy bins: thermal-epithermal and fast energy ranges) wherein, it is demonstrated that the advantage factor for the CTMFD (if borated) remains elevated at the 5–10x higher level for low and large shielding thicknesses and soft and hard neutron spectra.

The challenges of assessing adiposity in a clinical setting.

To tackle the burden of obesity-induced cardiometabolic disease, the scientific community relies on accurate and reproducible adiposity measurements in the clinic. These measurements guide our understanding of underlying biological mechanisms and clinical outcomes of human trials. However, measuring adiposity and adipose tissue distribution in a clinical setting can be challenging, and different measurement methods pose important limitations. BMI is a simple and high-throughput measurement, but it is associated relatively poorly with clinical outcomes when compared with waist-to-hip and sagittal abdominal diameter measurements. Body composition measurements by dual energy X-ray absorptiometry or MRI scans would be ideal due to their high accuracy, but are not high-throughput. Another important consideration is that adiposity measurements vary between men and women, between adults and children, and between people of different ethnic backgrounds. In this Perspective article, we discuss how these critical challenges can affect our interpretation of research data in the field of obesity and the design and implementation of clinical guidelines.

Biopsies from patients with sacral insufficiency fracture are characterized by low bone matrix mineralization and high turnover.

Sacral insufficiency fractures are known to occur primarily in older women without adequate trauma. While an association with low bone mineral density (ie, osteoporosis) has been reported, more detailed information on local bone quality properties in affected patients is not available. In the present study, core biopsies were obtained from the S1 sacral ala in patients with a bilateral sacral insufficiency fracture (type IV according to the fragility fractures of the pelvis classification) who required surgical stabilization. Dual energy X-ray absorptiometry (DXA) and laboratory bone metabolism analyses were performed. For comparison, control biopsies were acquired from skeletally intact age- and sex-matched donors during autopsy. A total of 31 biopsies (fracture: n = 19; control: n = 12) were evaluated by micro-computed tomography, histomorphometry on undecalcified sections, and quantitative backscattered electron imaging (qBEI). DXA measurements showed mean T-scores in the range of osteoporosis in the fracture cohort (T-scoremin -2.6 ± 0.8). Biochemical analysis of bone metabolism parameters revealed high serum alkaline phosphatase and urinary deoxypyridinoline/creatinine levels. In the biopsies, a loss of trabecular microstructure along with increased osteoid values were detected in the fracture patients compared with controls (osteoid volume per bone volume 5.9 ± 3.5 vs. 0.9 ± 0.5%, p <.001). We also found evidence of microfractures with chronic healing processes (ie, microcallus) as well as pronounced hypomineralization in the biopsies of the fracture cohort compared with the controls as evidenced by lower CaMean measured by qBEI (22.5 ± 1.6 vs. 24.2 ± 0.5wt%, p =.003). In conclusion, this high-resolution biopsy study provides evidence of local hypomineralization in patients with sacral insufficiency fractures, pointing to reduced fracture resistance but also a distinct phenotype other than the predominant loss of trabeculae as in postmenopausal osteoporosis. Our data highlight the importance of therapies that promote bone mineralization to optimally treat and prevent sacral insufficiency fractures.

Dual-energy CT in differentiating benign gallbladder wall thickening from wall thickening type of gallbladder cancer.

To evaluate the performance of dual-energy computed tomography (DECT) in differentiating non-acute benign from malignant gallbladder wall thickening (GBWT). This prospective study comprised consecutive adults with GBWT who underwent late arterial phase (LAP) and portal venous phase (PVP) DECT between January 2022 and May 2023. The final diagnosis was based on histopathology or 3-6 months follow-up imaging. DECT images in LAP and PVP were assessed independently by two radiologists. The demographic, qualitative, and quantitative parameters were compared between two groups Multivariate logistic regression was performed to determine the association between the aforementioned factors and malignant GBWT. Seventy-five patients (mean age 56 ± 12.8 years, 46 females) were included. Forty-two patients had benign, and 33 had malignant GBWT. In the overall group, female gender (p = 0.018), lymphadenopathy (p = 0.011), and omental nodules (p = 0.044) were significantly associated with malignant GBWT. None of the DECT features differed significantly between benign and malignant GBWT in overall group. In the xanthogranulomatous cholecystitis (XGC, n = 9) vs. gallbladder cancer (GBC) (n = 33) subgroup, mean attenuation value at 140 keV LAP VMI was significantly associated with malignant GBWT [p = 0.023, area under curve 0.759 (95%CI 0.599-0.919)]. DECT-generated quantitative parameters do not add value in differentiating non-acute benign from malignant GBWT. However, DECT may have a role in differentiating XGC from GBC in a selected subgroup of patients. Further, larger studies may be necessary to confirm these findings. In patients with non-acute gallbladder wall thickening in whom there is suspicion of xanthogranulomatous cholecystitis (XGC), DECT findings may allow differentiation of XGC from wall thickening type of gallbladder cancer. Differentiation of benign and malignant gallbladder wall thickening (GBWT) at CT is challenging. Quantitative dual energy CT (DECT) features do not provide additional value in differentiating benign and malignant GBWT. DECT may be helpful in a subgroup of patients to differentiate xanthogranulomatous cholecystitis from gallbladder cancer.

How Bone Mineral Density Affect Periodontal Health in Postmenopausal Women using DEXA Scanning: A Digital Radiographic Study

Background: Periodontitis and osteoporosis are the diseases with common feature of both bone loss. However, the relation and extent between these diseases is still unclear. The purpose of present study was to evaluate the relationship between periodontal status and systemic bone mineral density in postmenopausal women. Methods and Material: A total of 40 postmenopausal women aged between 45–60 Years (50.6±4.6 years) were randomly selected from the department of periodontics. All women were examined for periodontal status and Bone Mineral Density(BMD). Periodontal status was examined by recording plaque index(PI), gingival index(GI), pocket probing depth(PPD), clinical attachment level (CAL) and alveolar bone loss (ABL). BMD was measured by Dual Energy X-ray absorptiometry (DEXA) scan for bone mineral density score. (T-score) values. The recorded data for T-score and periodontal status were subjected to statistical analysis for correlation and regression analysis. Results: The results showed that there was no statistically significant correlation between Probing depth (r= -0.168, P &gt; 0.05), gingival index (r= -0.441, P&gt;0.05), and plaque index (r= -0.345, P&gt;0.05) with T-score; whereas CAL (r= -0.604, P&gt;0.05) and ABL (r= -0.637, P&gt;0.05) was significantly correlated with T-score. Conclusion: In the present study systemic BMD was related to ABL and CAL, suggesting that postmenopausal bone loss can be a risk indicator for periodontal disease.

P-632 Characterization of body composition by dual energy x-ray absorptiometry (DXA) of infertile women with history of repeated implantation failure

Abstract Study question Does body composition differ between fertile and infertile patients with history of repeated implantation failure (RIF)? A pilot study. Summary answer Compared to fertile, infertile women with history of RIF show differences in tissue distribution and bone mineralization (BM). What is known already It is known that being under/overweight or obese increases the risk of RIF or miscarriage probably due to the key role that adipose tissue exerts in reproduction. Body mass index (BMI) is the most used metric to define anthropometric characteristics; however, it represents a poor indicator of body composition leading to the risk of miscalculating the percentage of fat mass (FM) and underestimating the risk of reproductive failure. This study aims to analyze body composition of infertile patients by DXA, the gold standard for FM calculation and location, providing a 3-dimensional picture of body organ densities. Study design, size, duration This observational pilot study was conducted over 11 months. Sixty-six women were recruited and underwent all assessments. Participants/materials, setting, methods Out of 66 enrolled women, 16 were RIF (according to ESHRE 2023 criteria; here defined infertile women [IW] and aged 38.88±4.62 years), and 50 were women who already had at least one live birth (here defined fertile [FW] and aged 31.74±6.36 years), with varying weight ranges and BMI. The patients underwent an assessment of body composition by DXA Primus, X-ray densitometer; software v1.2.2, Osteosys Co., Ltd. Statistical analysis was conducted using IBM SPSS v21.0. Main results and the role of chance From FM percentage (FM%) analysis, 50% of the IW were normal-weight (NW - BMI 18.5-25, FM%&amp;lt;30), 31.25% were NW-obese (NWO - BMI 18.5-25, FM%≥30), and 18.75% were Obese (BMI≥25, FM%≥30). Of the FW, 48% were NW, 32% NWO, and 20% obese. Based on the Shapiro-Wilk normality test, independent samples t-test analysis or Wilcoxon’s nonparametric tests were adopted. Differences in body composition emerged between the IW and FW groups. IW showed a significant increase in right leg lean (7.38±1.03 vs 6.77±1.13, p &amp;lt; 0.05) and in left total tissue (28.02±5.3 vs 18.94±9.19, p &amp;lt; 0.0001) compared with FW. In contrast, FW showed a significant increase in left trunk tissue (22.85±8.33 vs 14.17±7.03, p &amp;lt; 0.0001), and in left and right trunk BM (367.6±90.47 vs 306.66±69.67, p &amp;lt; 0.005 and 368.35±94.49 vs 313.73±76.98, p &amp;lt; 0.012) versus IW. Limitations, reasons for caution Given the pilot nature of the study, its small sample size may influence the outcomes. Moreover, individual variations beyond dietary factors could contribute to the difference, including age. Additionally, our findings should be confirmed in a broader population. Wider implications of the findings The significant differences observed in IW compared to FW regarding body composition, especially concerning the tissue distribution and BM, encourage further investigations, particularly exploring possible hormonal, metabolic, and genetic correlations, to better understand the distinctive characteristics of this group. Trial registration number ClinicalTrials.gov NCT01890070.