Large Diameter Research Articles

VEGFA gene variants are associated with breast cancer progression.

Angiogenesis is recognized as a hallmark of cancer, and vascular endothelial growth factor (VEGF) is a key regulator of the angiogenic process and is related to cancer progression. Anti-VEGF therapy has been tried but with limited success and without useful stratification for angiogenesis markers. Further, the landscape of VEGF single nucleotide polymorphisms (SNPs) in breast cancer and their clinical relevance is not well studied, and their relation to tissue-based angiogenesis markers has not been explored. Here, we studied a selection of VEGFA SNPs in nontumor lymph nodes from a population-based breast cancer cohort (n = 544), and their relation to clinicopathologic variables, vascular tissue metrics, and breast cancer-specific survival. Two of the SNP candidates (rs833068GA genotype and rs25648CC genotype) showed associations with angiogenesis tissue markers, and the VEGFA rs833068GA genotype was associated with breast cancer-specific survival among ER-negative cases. We also found trends of association between the rs699947CA genotype and large tumor diameter and ER-negative tumors, and between the rs3025039CC genotype and large tumor diameter. Our findings indicate some associations between certain VEGF SNPs, in particular the rs833068GA genotype, and both vascular metrics and patient survival. These findings and their potential implications need to be validated by independent studies.

Experimental Study and Neural Network Predictions of Early-Age Behavior of Microexpansion Concrete in Large-Diameter Steel Tube Columns

The improved mechanical performance of concrete-filled steel tube (CFST) components has led to their widespread application in megastructures. Therein, CFST hybrid arch bridge has become an optimal selection of large span bridges. Nonetheless, for massive concrete poured in CFST members with large diameter, the thermal cracking and sustained rising temperature caused by early hydration heat of core concrete are urgently required to be studied. The two large-diameter CFST columns in this work, each having a diameter of 2.1 m, had their temperature and strain fields recorded in-situ. An existing CFST arch bridge served as the model for the two CFST columns’ design. Additionally, early-age characteristics of several scaled CFST columns with varying diameters were documented. A multi-field finite element (FE) model that combines linked chemical (hydration), heat, and mechanical fields is suggested in order to properly characterize the evolutions of temperature and strain fields. The model is validated by comparing the in-situ measurements with the numerical results. Finally, to investigate the affect factors on the hydration temperature of core concrete in CFST columns, early-age hydration behaviors of CFST columns was simulated using the validated FE models input parameters as water to cement ratio (w/c), cement dosage, heat release of cement and diameter of CFST columns. Based on the numerical results under the input parameters mentioned, the LSTM neural network was constructed, and the hydration temperature variances computed by FE models were selected as the input dataset. Afterwards, the temperature variance of core concrete of CFST columns was predicted using the established LSTM network. It is discovered that the LSTM neural network that was previously constructed was able to predict the peak temperature of CFST columns as well as the hydration temperature of CFST specimens with respect to time.

Value of radiofrequency ablation for treating locally recurrent thyroid cancer: a systematic review and meta-analysis for 2-year follow-up.

To evaluate the safety and efficacy of radiofrequency ablation (RFA) in treating locoregional recurrent thyroid cancer (LRTC) after a 2-year follow-up time. PubMed, Embase and Cochrane Library were searched from inception until 20 September 2022 to find studies reporting the safety and efficacy of RFA in LRTC patients after a 2-year follow-up. Two radiologists performed the data extraction and methodological quality assessment according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We analyzed 6 studies, 229 LRTC patients with 319 locally recurrent tumors were treated with RFA. The mean follow-up time of each study was ≥24 months. The pooled changes in the largest diameter and volume were 7.22 mm (95% confidence interval (CI), 6.35-8.09 mm) and 164.28 mm3 (95% CI, 87.78-240.77 mm3), respectively; the pooled volume reduction rate was 95.03% (95% CI, 87.56-102.49%). The total complete disappearance rate after treatment was 92% (95% CI, 83-100%). The pooled decrease of serum thyroglobulin levels was 0.02 ng/ml (95% CI, -0.00-0.04 ng/ml). The pooled proportion of recurrence rate was 6% (95% CI, 0-13%). The pooled complication rate was 5% (95% CI, 0-10%). The major complications were voice change and hoarseness, only one patient developed permanent vocal cord paralysis; minor complications were cough and pain. Ultrasound-guided RFA is an effective and safe treatment for LRTC based on 2-year follow-up results.

Biomimetic fractal pillars for the thermal–hydraulic enhancement of a vapor chamber

Owing to their remarkable thermal–hydraulic performance, vapor chambers have diverse applications, especially for cooling electronic devices. However, the performances of circular and noncircular pillars throughout the entire vapor chamber under identical wick volume conditions have been compared in very few studies. In this study, a series of noncircular pillar arrays featuring biomimetic tree-like fractal networks is introduced. The incorporation of fractal pillars significantly enhances the thermal–hydraulic performance of the vapor chamber because the gas–liquid interface area is extended. Compared to a vapor chamber with circular pillars, the maximum condensation surface temperature difference, total thermal resistance, and liquid pressure drop of this vapor chamber with fractal pillars are reduced by up to 57.8 %, 13.8 %, and 10.9 %, respectively. In particular, with large branch levels and pillar diameters, the fractal structure is pivotal for boosting the overall performance. When the number of pillars is increased, the fractal structure's impact on the thermal performance reaches a limit, whereas its boosting effect on the flow performance weakens. This study is a pioneering exploration of the application of stretched geometries in pillar-type vapor chambers, with fractal pillars utilized in showcase demonstrations.

Potential of the Thoracoepigastric Vein as a Drainage Vein in Breast Reconstruction With a Free Flap: An Anatomical Study Using Computed Tomography.

The recipient vessel choice is very important when performing free-flap breast reconstructions. Usually, the concomitant vein of the recipient artery is anastomosed, and mismatches in the diameter are occasionally observed. We consider the thoracoepigastric vein (TEV) as a potential useful recipient vein. The use of the TEV is not a novel technique. It has been used by surgeons for free-flap anastomoses in the axillary region, but usually as an anastomotic site for the second vein. However, anatomical findings such as TEV diameter, its deficiency rate, and influence on mastectomy are not clear. In this study, computed tomography (CT) was performed to evaluate the use of the TEV as a recipient vein for breast reconstruction. The medical records of patients who underwent breast reconstruction with free-flap transfer were retrospectively evaluated. In most cases, CT was performed using a tissue expander inserted after mastectomy. The TEV was considered suitable if its diameter on the mastectomy side was >1 mm and the vertical distance from the most distal slice level where the TEV could be seen at the third costal cartilage height of the parasternal region was <50 mm. Sixty-six sides of 33 patients were evaluated. The mean age of the patients was 49.3 ± 5.1 years. The TEV was used in five flaps. TEV diameters were not significantly different between the left and right sides (1.85 ± 0.53 vs. 1.82 ± 0.6, respectively, p = 0.836). On the mastectomy side, eight (25%) TEVs were injured, but only three (8.6%) were considered unavailable. On the healthy side, 96.4% TEVs were available. TEVs may be a good choice as vein anastomosis targets for breast reconstruction with a free flap because of their relatively large vessel diameter. UMIN-CTR: R000061573.

Numerical study on the motion of two parallel spherical particles with different diameters in upward flow

The settling of particles is related to many industrial processes and research fields. However, due to the complex particle–particle and particle–fluid interactions, the settling mechanism of particles in flowing fluids is not fully understood. This article conducts numerical research on the settling process of two particles with different diameters in parallel in upward flow using the immersion boundary method. The numerical method was validated against experimental results including one particle settling, two parallel particles settling, and two series particles settling. The effects of large particle diameter, upward flow velocity, and initial particle spacing on the settling process were explored. The results indicate that the two particles with same diameter will repel each other when settling in upward flow. Moreover, when the diameters differ, the two particles can experience both attractive and repulsive interactions. The larger the diameter of the large particle, the stronger its attractive influence on the small particle. When the diameter of large particle d2 = 3.0d1, large particle only has an attractive effect on small particle. The wake of each particle forms a distinct velocity boundary with the upward fluid. As the upward flow velocity increases, the interactions between the two particles become increasingly intense. With increasing initial spacing between the particles, their mutual interactions gradually weaken.

Analysis on heat transfer enhancement mechanism in a cross-wavy primary surface heat exchanger based on advection thermal resistance method

This paper numerically investigates the flow and heat transfer characteristics in the primary surface heat exchanger (PSHE) with cross-wavy (CW) structures. The comprehensive performance affected by hydraulic diameters is evaluated. Moreover, the airflow shuttling behavior at the mixing area of CW-type PSHE is discussed, showing rapid heat transfer enhancement. The advection thermal resistance method and local thermal resistance analysis is proposed, while the impacts of longitudinal pitch and flowrates are considered. Results show that the case with a large hydraulic diameter displays much better comprehensive performance at lower flowrates. When raising the hydraulic diameter from 1.58 mm to 15.8 mm, the heat transfer rate per unit pumping power grows by 36.1 %. However, the priority of large channel is gradually disappeared after increasing the flowrates. Meanwhile, the larger longitudinal pitch of the CW channel may result in pronounced improvement on the heat transfer performance due to the presence of airflow shutting behavior at the mixing area as well as the secondary flow near the channel boundary layers. When no airflow shuttling exists, very high advection thermal resistance region can be observed due to the formation of boundary layers. It can be recognized that the case with airflow shuttling behavior can display similar heat transfer improvement compared to that with increasingly high Reynolds numbers, yet the pressure loss is rarely increased.

Postoperative Management of Aneurysmal Subarachnoid Hemorrhage

Delayed cerebral ischemia(DCI) is one of the most significant complications of subarachnoid hemorrhage. Despite significant evolution in understanding DCI pathophysiology, vasospasm affecting cerebral vessels of large and moderate diameters remain the only clinically measurable component of DCI and is therefore the primary target for intervention in the postoperative management of subarachnoid hemorrhage. In Japan, fasudil hydrochloride and ozagrel sodium are widely used to prevent vasospasms; however, their effects are sometimes insufficient. Clazosentan, a selective endothelin receptor subtype A antagonist, reduces vasospasm-related morbidity and all-cause mortality following aneurysmal subarachnoid hemorrhage. This was demonstrated in a recent randomized phase 3 trial, leading to the approval of clazosentan by the Pharmaceuticals and Medical Devices Agency in Japan. Recent advances in our understanding of subarachnoid hemorrhage will facilitate improved management to reduce the incidence of DCI.

Detection and characterization of detached tidal dwarf galaxies

Tidal interactions between galaxies often give rise to tidal tails, which can harbor concentrations of stars and interstellar gas resembling dwarf galaxies. Some of these tidal dwarf galaxies (TDGs) have the potential to detach from their parent galaxies and become independent entities, but their long-term survival is uncertain. In this study, we conducted a search for detached TDGs associated with a sample of 39 interacting galaxy pairs in the local Universe using infrared, ultraviolet, and optical images. We employed IR colors and UV/optical/IR spectral energy distributions to identify potential interlopers, such as foreground stars or background quasars. Through spectroscopic observations using the Boller and Chivens spectrograph at San Pedro Mártir Observatory, we confirmed that six candidate TDGs are at the same redshift as their putative parent galaxy pairs. We identified and measured emission lines in the optical spectra and calculated nebular oxygen abundances, which range from log(O/H) = 8.10 ± 0.01 to 8.51 ± 0.02. We have serendipitously discovered an additional detached TDG candidate in Arp72 using available spectra from SDSS. Utilizing the photometric data and the CIGALE code for stellar population and dust emission fitting, we derived the stellar masses, stellar population ages, and stellar metallicities for these detached TDGs. Compared to standard mass-metallicity relations for dwarf galaxies, five of the seven candidates have higher than expected metallicities, confirming their tidal origins. One of the seven candidates remains unclear due to large uncertainties in metallicity, and another has stellar and nebular metallicities compatible with those of a preexisting dwarf galaxy. The latter object is relatively compact in the optical relative to its stellar mass, in contrast to the other candidate TDGs, which have large diameters for their stellar masses compared to most dwarf galaxies. The derived stellar population ages range from 100 Myr to 900 Myr, while the inferred stellar masses are between 2 × 106 M⊙ and 8 × 107 M⊙. Four of the six TDGs are associated with the gas-rich M51-like pair Arp 72, one TDG is associated with a second M51-like pair Arp 86, and another is associated with Arp 65, an approximately equal mass pair. In spite of the relatively low stellar masses of these TDGs, they have survived for at least 100–900 Myrs, suggesting that they are stable and in dynamical equilibrium. We conclude that encounters with a relatively low-mass companion (1/10th–1/4th of the mass of the primary) can also produce long-lasting TDGs.

Clinical characteristics and treatment outcomes of angioleiomyoma of the female genital tract: a retrospective cohort study

BackgroundAngioleiomyoma, a benign tumour composed of smooth muscle cells and thick-walled vessels, is expected to be very rare in the female genital tract. This study aimed to describe the clinicopathological features and treatment outcomes of angioleiomyoma in the female genital tract.MethodsWe retrospectively reviewed 89 women with angioleiomyoma in the genital tract who were treated at Third Xiangya Hospital of Central South University between July 2008 and October 2023. Symptom remission rate was the primary outcome of the study.ResultsAngioleiomyomas accounted for 0.6% of leiomyomas of the female genital tract. The average age of the 89 women was 41.8 ± 8.7 years. Seventy women (78.7%) had a history of uterine surgery, of whom two patients had removed uterine angioleiomyoma by laparoscopic myomectomy. The angioleiomyomas of 61 (68.5%) women were located in the uterine corpus, 17 (19.1%) in the broad ligament, 10 (11.2%) in the cervix and only 1 (1.1%) in the vagina. Abnormal uterine bleeding was the main clinical manifestation of angioleiomyomas located in the uterine corpus or cervix, whereas the main clinical manifestation of angioleiomyomas in the broad ligaments was pelvic mass. Of the 89 women, 59 underwent surgery to preserve the uterus, and 30 underwent total hysterectomy or subtotal hysterectomy. The intraoperative blood loss was more than 500 ml (700–4,500 ml) in six women. The symptom remission rate was 100% after surgery. Among the 59 women with preserved uterus, 8 showed multiple uterine leiomyomas during follow-up, but it was difficult to determine whether they were angioleiomyomas. Angioleiomyomas recurred in one women who underwent total hysterectomy.ConclusionAngioleiomyoma is rare in the female reproductive tract, and patients may present with diverse symptoms, which are related to the location of the tumour. Hysterectomy and myomectomy are both effective treatment methods, but the risk of intraoperative bleeding should be recognised for multiple lesions and those with large diameters. Relapse may occur in some patients.

Primerjava ultrazvočnega merjenja premera spodnje votle vene in merjenja sestave telesa z metodo bioelektrične impedance za oceno tekočinskega stanja pri novorojenčkih

Background: Neonatal medical conditions often disrupt the physiological processes that regulate fluid balance, so assessing fluid status in sick neonates is important for clinical management. In clinical practice we use clinical signs, which, however, on their own, do not provide a reliable assessment of fluid status. We aimed to compare two methods: i) diameters and collapsibility index of vena cava inferior (VCI) measured by ultrasonography and ii) analysis of body composition by bioelectrical impedance (BIA) and to evaluate their relation to changes in body mass. Methods: In a cohort-prospective clinical trial we included 27 neonates aged 1–7 days with various pathologies. Ultrasound measurements of VCI transversely and longitudinally, measurements of body composition by BIA and measurements of body mass were performed in each subject at least three times with an interval of 24–72 hours. Simultaneous measurements of the same subject were then analysed and evaluated. Results: The average proportion of total body water (TBW) decreased in the first days after birth, from 80.3% (Day 1) to 73.1% (Day 8) (p = 0.006). The decrease in the average proportion of extracellular water (ECW) in the first days after birth was not statistically significant. The association between ECW and body mass over time was statistically significant (p &lt; 0.001). The association between transversely measured large VCI diameter during inspiration, body mass, and ECW was statistically significant (p = 0.024). No statistically significant association with ECW or body mass was proven for the other ultrasound-measured variables. Conclusions: By measuring body composition with BIA, we confirmed the reduction of the average proportions of TBW after birth and the association between body mass, ECW, and transversely measured maximal diameter of VCI during inspiration. BIA is an appropriate method for monitoring fluid status in a newborn. Additional research on a larger number of subjects is needed to define the significance of VCI measurements for assessing fluid status.

Physicochemical Characteristics of Titania Particles Synthesized with Gelatin as a Template Before and After Regeneration and Their Performance in Photocatalytic Methylene Blue

TiO2 material has an important position in the processing of methylene blue waste because it is economical, has abundant polymorphs, high sustainability and supports green chemistry applications. Mesoporous TiO2 is a porous material that has higher effectiveness than other TiO2 because the pore structure has a large diameter at the nano scale (2-50 nm) with a regular shape so that the surface area and pore volume are greater than the average for other TiO2. The synthesis of mesopore TiO2 material has so far used the sol-gel route with synthetic pore directing agents such as P123 which can be replaced with gelatin as a cheaper and safer pore directing agent with high sustainability and abundance. Based on the description above, this research aims to photodegrade methylene blue using mesoporous TiO2 (m-TiO2) nanoparticles which were prepared by the sol–gel method using gelatin and P123 as template. X-ray diffraction (XRD), scanning electron microscopy (SEM), Electron dispersive X-Ray (EDX), and UV–vis spectroscopy techniques were used to characterize the samples. Photocatalytic activities of samples for methylene blue degradation were investigated. The catalyst before and after regeneration will be studied so that the effect of regeneration on the results of methylene blue photocatalysis with m-TiO2 can be determined. XRD results confirmed the formation of the anatase and rutile phase for the TiO2 nanoparticles, with crystallite sizes larger after regeneration in the range of 9–21 nm. The large particle size was after regeneration due to the promotion by high temperature treatment. TiO2 nanoparticles showed the best photocatalytic activity on the first use to 91% and remained stable after four cycles with photodegradation efficiency up to 76% based on the measured UV-Vis spectroscopy. TiO2 as synthesis could be the best candidate for catalyst with the high performance after multicycle regeneration. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Do emptying bottles show self-induced liquid rotation?

An inverted liquid bottle with a small neck diameter empties through periodic admission of air bubbles at the neck, followed by liquid discharge, a process termed ‘glugging’. In contrast, a large Taylor bubble rises to the air–water interface in the bottle for large neck diameters, followed by an instant interface collapse and a chaotic liquid discharge. We numerically find that a spiral large-scale rotating structure due to churning motion develops in the liquid during time evolution in an emptying bottle, though an initial swirl is not imposed. The induced structure is strong for a large neck bottle, and the circulation strength is maximum near the neck region. The spiral structure’s strength decreases for small neck diameters, and a pure oscillatory ‘glugging’ mode is preserved. The high circulation strength near the neck region for the large neck bottle causes liquid to accelerate and is the reason for the existing empirical models on liquid discharge to deviate from experimental observations.

Experimental and theoretical analysis of charge length on single-hole vibration amplitude from underground deep-hole blasting

Deep-hole blasting, characterized by large diameter and long charge length, is a prevalent practice in large-scale underground mining. However, the increasing charge length in each borehole, together with the growing charge weight, necessitates a heightened focus on the induced vibration effects. Understanding the impact of long charge length on induced vibration in comparison with traditional vibration characteristics is crucial for the safety control of deep-hole blasting. Therefore, experiments involving 6 charge lengths and 4 monitoring stations were conducted in an underground mine to clarify the variation of waveform and peak particle velocity (PPV). The entire borehole waveform superposed by the short charge elements was theoretically calculated and compared with the measured waveforms. The exact full-field model was further used to gain a comprehensive understanding of the effect of charge length and the related parameters of initiation positions and velocity of detonation (VoD). The experimental data and model analysis allow the following conclusions: (1) the effect of charge length on amplitude is highly dependent on the Mach wave, irrespective of varying initiation positions and VoDs; (2) an increase in the charge length does not necessarily lead to an increase of the PPV in the far-field, but it would result in a faster attenuation rate below a certain length; (3) given a constant charge weight, a greater length-to-diameter ratio of the explosive column results in a smaller vibration amplitude; (4) the appropriate duration of the explosive pressure should be considerably longer than the actual duration for investigating blast vibration.

Experimental study on ignition and flame propagation of premixed ammonia ignited by Direct-Injected diesel in an optical rapid compression Machine

Ammonia (NH3) is considered as one of the most promising zero-carbon fuels for internal combustion engines. Based on diesel engine modification, The ammonia/diesel dual-fuel mode with port injection of ammonia and in-cylinder direct injection of diesel has been proven to be the most feasible strategy. In this paper, the effects of ignition and flame propagation of premixed ammonia ignited by direct-injected diesel were studied based on an optical rapid compression machine (RCM). The results show that the spray and distribution of diesel play the key role in the ignition and flame propagation of NH3/diesel dual fuels combustion. For total excess air ratio (λT) of 1.0, the ignition delay of NH3/diesel with high energy ratio of ammonia (ER of 95 %) was much shorter than ER of 66 % which was mainly due to the low injection pressure of diesel. Under the same injection pressure, with the large nozzle diameter of diesel injector of 0.28 mm, the ignition delay of NH3/diesel will be shortened significantly. When the ER is low, the combustion process presents the characteristics similar to the multi-point compression combustion. When the ER rises to 83 %, the combustion process is mainly dominated by NH3 premixed combustion, and diesel mainly plays the role of ignition. Reducing the background pressure and temperature to 4 MPa and 887 K, respectively, NH3 is not able to be ignited by diesel.

Particle size distribution effects on the light scattering properties in non-diluted colloidal suspensions: A numerical study

The static light scattering technique potentially offers a nondestructive evaluation of a particle size distribution in dense colloidal suspensions. Understanding the size distribution’s correlation with the light scattering properties and modeling electromagnetic scattering with high accuracy and efficiency are crucial for technique development. The polydisperse dependent scattering theory (DST) is an accurate model, but its calculation is costly. We aim to numerically examine the size distribution effects on the scattering properties of dense suspensions up to the volume fraction of 20% in the near-infrared wavelength of 600–1000 nm using three electromagnetic models: the polydisperse and monodisperse DST, and the local monodisperse approximation (LMA). We considered various size distributions in Gaussian and logarithmic forms with constant standard deviations of 21 nm and 101 nm in the mean diameter range of 75–700 nm by shifting the distribution while keeping its shape. We showed that the monodisperse approximation is invalid at a small mean diameter of less than 200 nm, even at the sharp Gaussian distribution. It suggests the strong size distribution effects. Meanwhile, the approximation holds at a large diameter of more than 650 nm, even at the broad logarithmic distribution. We showed that the LMA results nicely agree with the polydisperse DST results for all the current conditions. At the same time, the LMA calculations are over a thousand times faster than the polydisperse DST because the LMA reduces the sum calculation over particle diameter pairs. Thus, the LMA is a great candidate for the electromagnetic model.

TiO2 nanoparticles synthesized on graphene nanosheets with varied crystallinity for photocatalytic degradation of MB dye

The incorporation of graphene into titania enhances photocatalytic activity, although the role of graphene remains debated. This study reconciles conflicting explanations in the literature and elucidates the improved photocatalytic behavior of titania nanoparticles supported on graphene sheets with varied crystallinity for the degradation of Methylene Blue (MB) dye. Specifically, crystalline graphene (ExG) and near-amorphous graphene (rGO, Ex-rGO), derived through physical and chemical methods, respectively, were employed as templates during the synthesis of titania (TiO2) nanoparticles. The rGO and Ex-rGO exhibited fewer graphene layers (∼3) than ExG (∼47 layers). The resulting TiO2/Ex-rGO and TiO2/rGO nanocomposites demonstrated significantly higher MB dye degradation (92.1 % and 79.2 %) than the unmodified TiO2 (60.5 %) and TiO2/ExG (70.7 %) after 2 hours of UV exposure. This study identified alterations in the mesoporous network of titania upon the incorporation of graphene, characterized by widely open pores in TiO2/rGO and TiO2/Ex-rGO with large average pore diameters of 12.99 nm and 13.78 nm, respectively, compared to the nearly blocked pores with a narrow diameter of 7.89 nm in reference TiO2. The enhanced photocatalytic activity in graphene-templated titania was attributed to rapid intra-porous molecular diffusion, a previously unreported factor. Additionally, nearly-amorphous rGO was identified as a superior template over ExG due to crystalline/amorphous heterojunctions in TiO2/rGO and TiO2/Ex-rGO, leading to reduced electron-hole recombination. Finally, a proposed computational approach estimated ‘accessible’ porosity, and Knudsen diffusion coefficients for the synthesized photocatalysts (reference-TiO2: TiO2/ExG: TiO2/rGO: TiO2/Ex-rGO as 1.05: 1: 1.48: 1.72), justifying the observed trends in MB dye degradation.

Inter-seasonal variation of rainfall microphysics as observed over New Delhi, India

This study analyzes the raindrop size distribution (RSD) characteristics over New Delhi by dividing the year into three seasons: PreM (March–May), monsoon (June–September), and PostM (October–February). Data from a Joss-Waldvogel Disdrometer, installed at IITM New Delhi, Rajendra Nagar, was used for three years (2021–2023). The observed raindrop spectra were fitted with three-parameter Gamma functions to obtain the RSD. ERA-5 and satellite data were also employed to establish atmospheric and cloud properties for the three seasons. The RSD for the monsoon season shows the highest concentration of midsize (1–3 mm diameter) drops and the highest mean rain rate. PostM has the least concentration of midsize and large (diameter >3 mm) drops. General statistics of rain integral parameters reveal high variability in rain rate (R) and mass-weighted mean diameter (Dm) values during the monsoon season. The mu-lambda scatter plots show considerable differences among the three seasons, indicating slightly distinct rainfall mechanisms in the three seasons. Z-R relations of the form Z = aRb were derived, with the highest coefficient (a) values observed for the PreM precipitation. The exponent (b) is found to be greater than unity in all three seasons. Rainfall was stratified based on rain rate. RSD gets broader with increasing R. Large drops are not found appreciably in the spectrum for R < 20 mm/h. A notable disparity between convective and stratiform RSD is evident. The values of rain integral parameters show considerable differences between the convective and stratiform regimes. A higher fraction of large drops is found for the stratiform rainfall in the PreM season compared to the other two seasons. CAPE, water vapor, surface temperature, and surface winds were higher during PreM and monsoon months compared to PostM. The distribution of differential temperature (δT) indicates that clouds with significant depth are found in PreM and monsoon seasons but are often lacking during PostM.

Aspiration tubing diameter is a key determinant of vacuum pressure and is associated with procedural outcome in mechanical thrombectomy for large vessel occlusion: An experimental and cohort study.

We (1) evaluated the effect of aspiration tubing diameter on intraluminal pressure and (2) compared thrombectomy outcomes in patients treated using small diameter tubing versus those treated using large diameter vacuum tubing. Intraluminal negative pressure was measured in a validated benchtop set up where consistency of negative pressure (inHg) was measured between static and dynamic aspiration. Static aspiration refers to activation of vacuum once the catheter is engaged with the clot. Dynamic aspiration refers to activation of vacuum when the catheter is slightly proximal to the clot. Four different sizes of vacuum tubing were trialed. We performed a retrospective analysis of consecutive patients who underwent mechanical thrombectomy. Procedural and functional outcomes were compared. The large diameter aspiration tubing held a consistent high negative pressure in static and dynamic aspiration (p = 0.152). Tubing types I to III were associated with a significant fall off in negative pressure between static and dynamic technique (p < 0.05). Two-hundred and five patients were included in the retrospective analysis; 124 (60%) underwent thrombectomy using small diameter vacuum tubing, and 81 (40%) using the large tubing. Mean thrombectomy time was shorter with the larger tubing [25.9 (17.9) minutes] versus the small tubing [37.5 (28.5) minutes, p = 0.002]. A greater proportion of patients had a thrombolysis in cerebral infarction score ≥2b in the group treated using the large tubing (78, 99%) than those with the small tubing (96, 78%, p < 0.001). Vacuum tubing diameter is linearly associated with intraluminal aspiration pressure. These findings have clinical significance as shown by increased recanalization rates and decreased thrombectomy times when large-diameter aspiration tubing is used. Shifting the paradigm toward a flow-based technique using large-bore vacuum tubing ought to be considered.

Endovenous thermal ablation mid-term outcomes for the treatment of large diameter incompetent great saphenous veins.

The aim of this study was to assess the efficacy and safety of endovenous thermal ablation (EVTA) in treating large diameter, ≥12mm, incompetent great saphenous vein (GSV) in comparison to smaller ones. A retrospective comparative study was undertaken including 196 patients (205 limbs) undergoing EVTA. According to maximum GSV diameter patients were divided into two groups (group A <12mm, group B ≥12mm). Primary outcome was anatomic success defined as absence of reflux of GSV. Secondary outcomes were complications, postoperative pain using the 10-cm Visual Analog Scale (VAS) and improvement of Venous Clinical Severity Score (VCSS) and Chronic Venous Insufficiency Quality-of-Life Questionnaire (CΙVIQ-20) scores assessed at 7- days, 1month, 12months and 24months postoperatively. 118 patients with GSV diameter <12mm (group A) and 87 with GSV diameter ≥12mm (group B) were included. Patients' demographics, CEAP classification and length of ablated vein did not differ between the groups. Preoperative VCSS and VAS pain score were significant greater in group B (6.03 vs 6.94, p = .04 and 5.21 vs 5.77, p = .032, respectively). No differences in adverse events were observed post-operatively among groups. GSV occlusion rate at 1month was 98.3% (SE 1.3%) in group A and 96.5 % (2.2%) in group B (p = .3), at 12months 95.7% (SE 2%) and 94.2% (SE 2.8%) (p = .5), and at 24months 94% (SE 2.4%) and 93.1% (SE 3%) (p = .4) respectively. Both groups experienced significant and similar improvement in their VCSSs and CIVIQ scores postoperatively. In a subgroup analysis among different EVTA and GSV >12mm, 1470nm endovenous laser ablation (EVLA) and radiofrequency ablation (RFA) showed comparable results in terms of occlusion rates, complications, VCSS and CIVIQ scores. Endovenous thermal ablation techniques are efective and safe in the treatment of GSV incompetence regardless the diameter of the GSV. Both 1470nm EVLA and RFA techniques performed similar outcomes.