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Castor stalk from hemp plants is an attractive lignocellulosic feedstock for biomass refining valorization due to its similar chemical composition to hardwoods. In this study, the castor stalk fibers were pretreated with efficient dual-functional ethanolamine to achieve delignification and swelling of the cellulosic fibers, followed by cellulase enzymatic digestion for biomass conversion. Experimental results showed that ethanolamine pretreatment at 160 °C for 1 h effectively removed 69.20 % of lignin and 43.18 % of hemicellulose. In addition to efficient delignification and removal of hemicellulose, the study also revealed that supramolecular structure of cellulose was another major factor affecting enzymatic hydrolysis performance. The lowered crystallinity (60-70 %) and swelled crystal sizes (2.95-3.04 nm) promoted enzymatic hydrolysis efficiency during the heterogeneous reaction process. Under optimal conditions (160 °C, 1 h; enzyme loading: 15 FPU/g substrate), promoted yields of 100 % glucose and over 90 % xylose were achieved, which were significantly higher than those obtained from untreated castor stalk. These findings highlighted the effectiveness of the dual-functional ethanolamine pretreatment strategy for efficient bioconversion of lignocellulosic feedstocks. Overall, this study provides valuable insights into the development of new strategies for the efficient utilization of biomass resources, which is essential for the sustainable development of our society.

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Tobacco stalks, as one of the annual economic crops rich in biomacromolecules such as cellulose and hemicellulose, are more difficult to decompose into cellulose fibers due to their high degree of lignification compared to other ordinary straw feedstocks, resulting in their underutilization. In this study, we developed a mild three-stage alkali­oxygen (AO) process to efficiently deconstruct the tobacco stalk cell walls. The process, involving alkaline dosages of 15 %, 10 %, and 3 % at each stage, effectively dissociated the cell walls and yielded cellulose fibers with high brightness (42.0 % ISO). The organics in the spent liquor, including lignin, hemicellulose, and small-molecular extracts, were isolated through acid/ethanol precipitation and organic solvent extraction. Lignin characterization by 2D HSQC NMR indicated that the majority of native ß-aryl ether linkages were preserved after AO treatment, making it suitable for producing chemicals or biofuels via depolymerization. Additionally, the small-molecular extracts contained numerous depolymerized products from lignin and carbohydrates, as well as bioactive compounds derived from the tobacco stalk. Overall, this mild, efficient, and eco-friendly process offers a promising approach for the valorization of tobacco stalks and similar biomass resources.

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Phalaenopsis is the most popular potted plant worldwide. However, its typically long stalks often lead to increased shipping costs and risks. This study investigates the effectiveness of varying the concentration, timing, and frequency of paclobutrazol (PP333) applications on shortening the stalk of Phalaenopsis Join Grace 'TH288-4'. Concurrently, it also examines the potential for producing visually appealing and single-flower potted phalaenopsis products by means of truncation. Mature phalaenopsis plants were moved to a cool room in the seventh week to induce flowering. Four experimental groups were established based on different PP333 application schedules: the control (CK) group, with reverse osmosis water application in the second week; the T2 group, with a single application in the second week; the T2T3 group, with applications in both the second and third weeks; and the T7T8 group, with applications in the seventh and eighth weeks. The PP333 concentrations used were 250, 500, 750, and 1000 mg·L-1, applied as foliar sprays. The results showed that the shortest stalks, measured from the base to the first flower, were observed in the T2 group treated with PP333 at 750 mg·L-1 and in the T2T3 group with PP333 at 500, 750, and 1000 mg·L-1. These treatments resulted in stalk lengths of 19.18-22.17 cm, which are 67.2-71.6% shorter than the controls. PP333 application had minimal effect on the stalk diameter, pedicel length, flower width, length, and length/width ratio. However, root diameter was thicker in plants treated with PP333 compared with the control plants. For producing single-flower phalaenopsis, a foliar spray of 750 mg·L-1 PP333 is recommended approximately a month before moving the plants to cooler conditions, followed by truncation, retaining only the first flower. As a result, this study establishes a PP333 treatment protocol for phalaenopsis, offering a strategy to effectively shorten the stalks.

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Background: Pituitary stalk interruption syndrome is a rare congenital anomaly of the pituitary gland characterized by growth hormones deficiency (with or without other pituitary hormone deficiencies) along with radiological features of a thin or interrupted pituitary stalk, an ectopic or absent posterior pituitary, or a hypoplastic or absent anterior pituitary. Case presentation: A 10-year-old baby boy came with short stature. The laboratory investigations were done and showed low growth hormones and low thyroid-stimulating hormone. MRI showed an ectopic posterior pituitary, a small hypoplastic anterior pituitary, and an absent pituitary stalk. Conclusion: Pituitary stalk interruption syndrome is a very rare entity. MRI is used to diagnose it. Early detection of this syndrome improve the patient symptoms especially before puberty.

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Pituitary stalk interruption syndrome is a rare, congenital abnormality. Early identification and treatment can improve patient prognosis and quality of life and prevent adverse effect on growth and development. The patient described is an 8-year-old child with a history of short stature.

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Lodging reduces maize yield and quality. The improvement in maize lodging resistance has proven to be instrumental in maximizing the yield potential of maize varieties under high-density planting. Tillage practices accommodate larger groups by enhancing soil conditions. This study aimed to elucidate the impact of subsoil tillage in reducing the maize stalk lodging rate. The maize cultivars Xianyu 335 (XY335) and Zhongdan2 (ZD2) were selected for field experiments including two tillage methods, shallow rotary (RT) and subsoil (SS), and two densities, 75,000 plants ha-1 (D1) and 105,000 plants ha-1 (D2), were set up to investigate and analyze the changes of maize lodging rate and the related indexes of lodging resistance under SS and RT conditions. The findings revealed that under high density, as compared to rotary tillage, SS tillage decreased the plant and ear height by 9.01-9.20 cm and 3.50-4.90 cm, respectively. The stalk dry matter accumulation was enhanced by 8.98%-24.98%, while stalk diameter between two and seven internodes increased by 0.47- 4.15 mm. Stalk cellulose increased by 11.83% -12.38%, hemicellulose increased by 6.7%-15.97%, and lignin increased by 9.86%-15.9%. The rind puncture and crushing strength improved by 3.11%-20.06% and 11.90%-27.07%, respectively. The bending strength increased by 6.25%-27.96% and the lodging rate decreased by 1.20%-6.04%. Yield increased by 7.58%-8.17%. At SS tillage when density increased, the index changes in ZD2 were mostly less than those in XY335. The rind penetration strength, bending strength, crushing strength, stalk diameter, and dry matter accumulation all had a negative correlation with the lodging rate. It suggested that SS tillage was beneficial to lodging resistance and, in combination with stalk lodging-resistant varieties, can effectively alleviate the problem of stalk lodging after increased planting density.

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Visual field defects are commonly present in patients with brain tumors, particularly due to direct compression on the optic apparatus. However, there are instances where brain tumors, despite not directly compressing the optic pathway, can still cause visual symptoms, albeit rarely reported but not uncommonly observed. These mechanisms are thought to be associated with increased intracranial pressure (IICP). We report a case of a 32-year-old man who presented with right blurred vision and was diagnosed with a right convexity meningioma. Upon reviewing his magnetic resonance images, we hypothesized that the indentation of the pituitary stalk on the optic chiasm and the stretching of the optic nerve, combined with a focal effect of IICP, could be responsible for his atypical visual field defect.

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BACKGROUND: Stalk lodging (the premature breaking of plant stalks or stems prior to harvest) is a persistent agricultural problem that causes billions of dollars in lost yield every year. Three-point bending tests, and rind puncture tests are common biomechanical measurements utilized to investigate crops susceptibility to lodging. However, the effect of testing rate on these biomechanical measurements is not well understood. In general, biological specimens (including plant stems) are well known to exhibit viscoelastic mechanical properties, thus their mechanical response is dependent upon the rate at which they are deflected. However, there is very little information in the literature regarding the effect of testing rate (aka displacement rate) on flexural stiffness, bending strength and rind puncture measurements of plant stems. RESULTS: Fully mature and senesced maize stems and wheat stems were tested in three-point bending at various rates. Maize stems were also subjected to rind penetration tests at various rates. Testing rate had a small effect on flexural stiffness and bending strength calculations obtained from three-point bending tests. Rind puncture measurements exhibited strong rate dependent effects. As puncture rate increased, puncture force decreased. This was unexpected as viscoelastic materials typically show an increase in resistive force when rate is increased. CONCLUSIONS: Testing rate influenced three-point bending test results and rind puncture measurements of fully mature and dry plant stems. In green stems these effects are expected to be even larger. When conducting biomechanical tests of plant stems it is important to utilize consistent span lengths and displacement rates within a study. Ideally samples should be tested at a rate similar to what they would experience in-vivo.

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Hydrogen-ethanol co-production can significantly improve the energy conversion efficiency of corn stalk (CS). In this study, with CS as the raw material, the co-production characteristics of one-step and two-step photo-fermentation hydrogen production (PFHP) and ethanol production were investigated. In addition, the gas and liquid characteristics of the experiment were analyzed. The kinetics of hydrogen-ethanol co-production was calculated, and the economics of hydrogen and ethanol were analyzed. Results of the experiments indicated that the two-step hydrogen-ethanol co-production had the best hydrogen production performance when the concentration of CS was 25 g/L. The total hydrogen production was 350.08 mL, and the hydrogen yield was 70.02 mL/g, which was 2.45 times higher than that of the one-step method. The efficiency of hydrogen-ethanol co-production was 17.79 %, which was 2.76 times more efficient than hydrogen compared to fermentation with hydrogen. The result provides technical reference for the high-quality utilization of CS.

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With the growing demand for sustainable development, tobacco stalks, as a resource-rich and low-cost renewable resource, hold the potential for producing high-value chemicals and materials within a circular economy. Due to the complex and unique structure of tobacco stalk biomass, traditional methods are ineffective in its utilization, making the pretreatment of tobacco stalk lignocellulose a crucial step in obtaining high-value products. This paper reviews recent advancements in various pretreatment technologies for tobacco stalk lignocellulosic biomass, including hydrothermal, steam explosion, acid, alkaline, organic solvent, ionic liquid, and deep eutectic solvent pretreatment. It emphasizes the impact and efficiency of these pretreatment methods on the conversion of tobacco stalk biomass and discusses the advantages and disadvantages of each technique. Finally, the paper forecasts future research directions in the pretreatment of tobacco stalk lignocellulose, providing new insights and methods for enhancing its efficient utilization.

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BACKGROUND: Microbes colonizing each compartment of terrestrial plants are indispensable for maintaining crop health. Although corn stalk rot (CSR) is a severe disease affecting maize (Zea mays) worldwide, the mechanisms underlying host-microbe interactions across vertical compartments in maize plants, which exhibit heterogeneous CSR-resistance, remain largely uncharacterized. RESULTS: Here, we investigated the microbial communities associated with CSR-resistant and CSR-susceptible maize cultivars using multi-omics analysis coupled with experimental verification. Maize cultivars resistant to CSR reshaped the microbiota and recruited Bacillus species with three phenotypes against Fusarium graminearum including niche pre-emption, potential secretion of antimicrobial compounds, and no inhibition to alleviate pathogen stress. By inducing the expression of Tyrosine decarboxylase 1 (TYDC1), encoding an enzyme that catalyzes the production of tyramine and dopamine, Bacillus isolates that do not directly suppress pathogen infection induced the synthesis of berberine, an isoquinoline alkaloid that inhibits pathogen growth. These beneficial bacteria were recruited from the rhizosphere and transferred to the stems but not grains of the CSR-resistant plants. CONCLUSIONS: The current study offers insight into how maize plants respond to and interact with their microbiome and lays the foundation for preventing and treating soil-borne pathogens. Video Abstract.

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Introduction: Ectopic posterior pituitary (EPP) is a rare congenital abnormality, sometimes associated with other midline defects, such as pituitary stalk interruption syndrome (PSIS), in which thin or absent pituitary stalk and anterior pituitary hypoplasia are combined to EPP. Most cases are sporadic, with few reports of familial cases, and many congenital hypopituitarism (CH) cases remain unsolved. Objective: To search for candidate genes associated with this condition, we performed trio-based whole-exome sequencing (WES) on patients with EPP, including two familial cases. Methods: This study included subjects with EPP and PSIS diagnosed by a simple MRI protocol (FAST1.2). We performed two distinct analyses in the trio-based WES. We looked for previously described genes associated with pituitary development. Next, we investigated the whole exome for variants inherited in a pattern consistent with a monogenic etiology. Results: Ten families were evaluated; eight were composed of a child with EPP and healthy parents, one has two affected siblings, and one family has a son and mother with EPP. When analyzing the previously described candidate variants associated with pituitary development, we found variants in GLI2 and FGFR1 in three families. We also found six other variants of interest in three patients: KMT2A, GALR3, RTN4R, SEMA3A, NIPBL, and DSCAML1. Conclusion: The analysis allowed us to find previously reported and not reported GLI2 variants, all inherited from healthy parents, which reinforces the incomplete penetrance pattern of GLI2 variants in the development of EPP and draws attention to possible future functional studies of those variants that have a recurrent expression in CH. We also found novel FGFR1 and SEMA3A variants that suggest an oligogenic mechanism in PSIS and EPP, as seen in patients with hypogonadotropic hypogonadism. We report the first case of a patient with Wiedemann-Steiner syndrome and PSIS, suggesting that the KMT2A gene may be related to pituitary development. Furthermore, the trios' analysis allowed us to find five other variants of interest. Future investigations may clarify the roles of these variants in the etiology of EPP and PSIS.

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BACKGROUND: Pituitary stalk interruption syndrome (PSIS) is a rare anatomical defect of the pituitary gland falling under the spectrum of holoprosencephaly phenotypes. It is characterized by a deficiency in anterior pituitary hormones, such as growth hormone, gonadotropins, and thyroid hormones. Due to the syndrome's rarity and nonspecific manifestations, there is a lack of standardized treatment strategies. Consequently, early diagnosis through imaging and on-time intervention are crucial for improving patients' outcomes. CASE SUMMARY: A 30-year-old man presented with absent secondary sexual characteristics and azoospermia. Laboratory evaluation revealed a deficiency in gonadotropins, while thyroid function was mostly within normal ranges. Magnetic resonance imaging of the pituitary gland showed pituitary stalk agenesis, hypoplasia of the anterior pituitary, and ectopic posterior pituitary, leading to the diagnosis of PSIS. Initially, the patient underwent 6 mo of gonadotropin therapy without significant changes in hormone levels and secondary sexual characteristics. Pulsatile gonadotropin-releasing hormone therapy was then administered, resulting in the detection of sperm in the semen analysis within 3 mo. After 6 mo, routine semen tests showed normal semen quality. The couple faced challenges in conceiving due to abstinence and underwent three cycles of artificial insemination, which was unsuccessful. They also attempted in vitro fertilization, but unfortunately, the woman experienced a miscarriage 10 wk after the embryo transfer. CONCLUSION: Early detection, accurate diagnosis, and timely treatment are crucial in improving the quality of life and fertility of PSIS patients.

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As one of the most important food crops in the world, rice yield is directly related to national food security. Lodging is one of the most important factors restricting rice production, and the cultivation of rice varieties with lodging resistance is of great significance in rice breeding. The lodging resistance of rice is directly related to the mechanical strength of the stalks. In this paper, we reviewed the cell wall structure, its components, and its genetic regulatory mechanism, which improved the regulatory network of rice stalk mechanical strength. Meanwhile, we analyzed the new progress in genetic breeding and put forward some scientific problems that need to be solved in this field in order to provide theoretical support for the improvement and application of rice breeding.

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For Bacterial Nanocellulose (BNC) production, standard methods are well-established, but there is a pressing need to explore cost-effective alternatives for BNC commercialization. This study investigates the feasibility of using syrup prepared from maize stalk as a valuable nutrient and sustainable carbon source for BNC production. Our study achieved a remarkable BNC production yield of 19.457 g L-1 by utilizing Komagataeibacter saccharivorans NUWB1 in combination with components from the Hestrin-Schramm (HS) medium. Physicochemical properties revealed that the obtained BNC exhibited a crystallinity index of 60.5 %, tensile strength of 43.5 MPa along with enhanced thermostability reaching up to 360 °C. N2 adsorption-desorption isotherm of the BNC displayed characteristics of type IV, indicating the presence of a mesoporous structure. The produced BNC underwent thorough investigation, focusing on its efficacy in addressing environmental concerns, particularly in removing emerging pharmaceutical pollutants like Metformin and Paracetamol. Remarkably, the BNC exhibited strong adsorption capabilities, aligning with the Langmuir isotherm and pseudo-second-order model. Thermodynamic analysis confirmed a spontaneous and endothermic adsorption process. Furthermore, the BNC showed potential for regeneration, enabling up to five recycling cycles. Cytotoxicity and oxidative stress assays validated the biocompatibility of BNC. Lastly, the BNC films displayed an impressive 88.73 % biodegradation within 21 days.

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Lodging largely affects yield, quality and mechanical harvesting of maize. Stalk strength is one of the major factors that affect maize lodging. Although plant cell wall components including lignin and cellulose were known to be associated with stalk strength and lodging resistance, spatial accumulation of specific lignin monomers and cellulose in different tissues and their association with stalk strength in maize was not clearly understood. In this study, we found that both G and S lignin monomers accumulate highest in root, stem rind and leaf vein. Consistently, most lignin biosynthetic genes were expressed higher in root and stem than in other tissues. However, cellulose appears to be lowest in root. There are only mild changes of G lignin and cellulose in different internodes. Instead, we noticed a dramatic decrease of S-lignin accumulation and lignin biosynthetic gene expression in 2nd to 4th internodes wherein stem breakage usually occurs, thereby revealing a few candidate lignin biosynthetic genes associated with stalk strength. Moreover, stalk strength is positively correlated with G, S lignin, and cellulose, but negatively correlated with S/G ratio based on data of maize lines with high or low stalk strength. Loss-of-function of a caffeic acid o-methyltransferase (COMT), which is involved in S lignin biosynthesis, in the maize bm3 mutant, leads to lower stalk strength. Our data collectively suggest that stalk strength is determined by tissue-specific accumulation of lignin monomers and cellulose, and manipulation of the cell wall components by genetic engineering is vital to improve maize stalk strength and lodging resistance.

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To investigate the effect of stalk type on the metallization degrees in FeCl3-derived magnetic biochar (MBC), MBC was synthesized via an impregnation-pyrolysis method using six different stalks. The Fe0 content in MBC significantly influenced its magnetic properties and ostensibly governed its catalytic capabilities. Analysis of the interaction between stalks and FeCl3 revealed that the variation in metallization degrees, resulting from FeCl2 decomposition (6.1%) and stalk-mediated reduction (20.7%), was directly responsible for the observed differences in MBC metallization. The presence of oxygen-containing functional groups and fixed carbon appeared to promote metallization in MBC induced by reduction. A series of statistical analyses indicated that the cellulose, lignin, and hemicellulose content of the stalks were key factors contributing to differences in MBC metallization degrees. Further exploration revealed that hemicellulose and cellulose were more effective than lignin in enhancing metallization through FeCl2 decomposition and reduction. Constructing stalk models demonstrated that the variance in the content of these three biomass components across the six stalk types could lead to differences in the metallization degree attributable to reduction and FeCl2 decomposition, thereby affecting the overall metallization degree of MBC. A prediction model for MBC metallization degree was developed based on these findings. Moreover, the elevated Si content in some stalks facilitated the formation of Fe2(SiO4), which subsequently impeded the reduction process. This study provides a theoretical foundation for the informed selection of stalk feedstocks in the production of FeCl3-derived MBC.

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Scientists and engineers encounter considerable environmental and economic obstacles stemming from the depletion of crude oil or petroleum fossil fuel reservoirs. To mitigate this challenge, alternative solutions like bio-oil-modified binder derived from biomass have been innovated. This research aims to examine the feasibility of using bio-oil-modified binder obtained from cotton stalk waste as a modifier. Various mechanical and physical tests, including penetration, softening point, ductility, and dynamic shear rheometer tests, were conducted on asphalt binder incorporating 5% and 10% bio-oil-modified binder. Wheel tracker, four-point beam fatigue, and dynamic modulus tests were used to evaluate asphalt mixture performance, including rutting, fatigue, and dynamic stiffness. A rolling bottle test (RBT) and asphalt binder bond strength (BBS) were used to assess moisture susceptibility. A bio-oil-modified binder enhanced ductility and penetration characteristics while reducing the softening point. With the addition of a bio-oil-modified binder, stiffness was reduced in parameters such as complex shear modulus and phase angle. In fact, for both specimens containing 5% and 10% bio-oil-modified binder, statistically significant differences were observed among the measured samples. As a result of this reduced stiffness, the modified asphalt binder is more suitable for low-temperature applications. Additionally, 5.8% increased at 10% and 3.1% at 5% CS. Bio-oil-modified binder, compared to virgin mixtures, supports equal rut resistance. However, the RBT and BBS tests revealed that the addition of bio-oil-modified binder increased the susceptibility of conventional asphalt binder to moisture. The findings suggest that bio-oil-modified binder can enhance asphalt binder properties in low-temperature regions, but further research is needed to improve moisture resistance.

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Introduction and importance: Pituitary stalk interruption syndrome (PSIS) is a rare congenital condition affecting the pituitary gland and its stalk, leading to hormonal imbalances. PSIS can present with a wide range of symptoms, including delayed puberty and short stature. Case presentation: This paper discusses two cases of PSIS in patients with a history of growth hormone deficiency. The first case is of a 26-year-old male presenting with fatigue and loss of appetite, while the second case is of a 14-year-old male presenting with delayed puberty. Blood tests revealed hormonal imbalances, and a subsequent MRI confirmed the diagnosis of PSIS. Hormonal supplements were prescribed to manage the condition, and follow-up appointments were scheduled to monitor progress. Clinical discussion: PSIS can present with a wide range of symptoms, and can be diagnosed at different ages. Early diagnosis and management of PSIS are crucial to prevent long-term complications such as short stature, impaired cognitive function, and infertility. The use of hormonal supplements, as seen in both cases, is essential to manage the hormonal imbalances associated with PSIS. Testosterone replacement therapy is used to treat hypogonadism, while thyroxine and hydrocortisone are used to manage hypothyroidism and adrenal insufficiency, respectively. Conclusion: Early diagnosis and management of PSIS through hormonal supplements are crucial to prevent long-term complications. It is essential to monitor patients' progress through follow-up appointments to ensure optimal management of the condition.

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Atrial fibrillation, the most common cardiac arrhythmia in the Western world, confers a 5-fold increase in stroke, mainly due to thrombus formation in the left atrial appendage. Early rhythm control is often beneficial in reducing adverse cardiovascular events in higher-risk populations. Here, we present a patient who was found to have a 1 cm stalk-like lesion in the left atrial appendage on transesophageal echocardiogram prior to electrical cardioversion. Using multiple cardiac imaging modalities, including cardiac magnetic resonance imaging and computed tomography, the mass was eventually determined to be a chronic resolving thrombus.