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Introduction: Music Performance Anxiety (MPA) is a prevalent condition among musicians that can manifest both psychologically and physiologically, leading to impaired musical performance. Physiologically, MPA is characterized by excessive muscular and/or autonomic tone. This study focuses on the cardiovascular blood pressure responses, autonomic tone and baroreceptor sensitivity changes that occur during musical performance due to MPA. Methods: Six professional pianists perform a piece for piano written only for the left hand by Alexander Scriabin. The following parameters have been studied during the performance: ECG, non-invasive beat to beat continuous arterial blood pressure and skin conductance. Sympathetic and parasympathetic autonomic flow was studied with Wigner-Ville analysis (W-V) from R-R ECG variability, and baroreceptor sensitivity with the Continuous Wavelet Transform (CWT). Results: During the concert a significant increase of heart rate, systolic, mean and diastolic arterial pressure were observed. No significant differences were found in skin conductance. The W-V analysis, which studies frequency changes in the time domain, shows a significant increase of sympathetic flow and a decrease of parasympathetic flow during the concert which is associated with a significant decrease in sympathetic and vagal baroreceptor sensitivity. Discussion: The study of cardiac variability using the Wigner-Ville analysis may be a suitable method to assess the autonomic response in the context of MPA, and could be used as biofeedback in personalized multimodal treatments.

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Food supplements are used to improve cognitive functions in age-related dementia. This study was designed to determine the Murraya koenigii leaves' effect on Alloxan-induced cognitive impairment in diabetic rats and the contents of oxidative stress biomarkers, catalase, reduced glutathione, and glutathione reductase in brain tissue homogenates. Wistar rats were divided into seven groups (six rats per group). Group I received saline water (1 ml, p.o.), Diabetes was induced in Groups II-VII with Alloxan (120 mg/kg/p.o). Group III was provided with Donepezil HCl (2.5 mg/kg/p.o.), Group IV, V, VI, and VII with Murraya koenigii ethanol extract (200 and 400 mg/kg/p.o.) and aqueous extract (200 and 400 mg/kg/p.o.), respectively, for 30 days. Behavior, acetylcholinesterase (AChE) activity, oxidative stress status, and histopathological features were determined in the hippocampus and cerebral cortex. Administration of Murraya koenigii ethanolic and aqueous extracts significantly (P<0.05, P<0.001) increased the number of holes crossed by rats from one chamber to another. There was an increase in the (1) latency to reach the solid platform, (2) number of squares traveled by rats on the 30th day, and (3) percentage of spontaneous alternation behavior compared to the control group. Administration for successive days markedly decreased AChE activity (P<0.05), decreased TBARS level, and increased catalase, GSH, and GR levels. Murayya koenigii could be a promising food supplement for people with dementia. However, more research into sub-chronic toxicity and pharmacokinetic and pharmacodynamics interactions is essential.

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This work aimed to develop new antibiotic-coated/ antibiotic-loaded hydroxyapatite (HAp) scaffolds for orthopaedic trauma, specifically to treat the infection after fixation of skeletal fracture. The HAp scaffolds were fabricated from the Nile tilapia (Oreochromis niloticus) bones and fully characterized. The HAp scaffolds were coated with 12 formulations of poly (lactic-co-glycolic acid) (PLGA) or poly (lactic acid) (PLA), blended with vancomycin. The vancomycin release, surface morphology, antibacterial properties, and the cytocompatibility of the scaffolds were conducted. The HAp powder contains elements identical to those found in human bones. This HAp powder is suitable as a starting material to build scaffolds. After the scaffold fabrication, The ratio of HAp to ß-TCP changed, and the phase transformation of ß-TCP to α-TCP was observed. All antibiotic-coated/ antibiotic-loaded HAp scaffolds can release vancomycin into the phosphate-buffered saline (PBS) solution. PLGA-coated scaffolds obtained faster drug release profiles than PLA-coated scaffolds. The low polymer concentration in the coating solutions (20%w/v) gave a faster drug release profile than the high polymer concentration (40%w/v). All groups showed a trace of surface erosion after being submerged in PBS for 14 days. Most of the extracts can inhibit Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA). The extracts not only caused no cytotoxicity to Saos-2 bone cells but also can increase cell growth. This study demonstrates that it is possible to use these antibiotic-coated/ antibiotic-loaded scaffolds in the clinic as an antibiotic bead replacement.

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There are no specific and sensitive biomarkers for arteritis, and the occurrence of arteritis in nonclinical toxicological studies of a candidate drug makes development of the drug very difficult. However, we showed in a previous study that the high signal intensity region around the artery on magnetic resonance imaging (MRI) could be a candidate biomarker for detection of arteritis. The present study was conducted to clarify the details of midodrine hydrochloride (MH)-induced arteritis lesions and whether arteritis induced by a mechanism other than the vasodilatory effect, which was evaluated in a previous study, could be detected by MRI. MH is a selective peripherally acting alpha-1 adrenergic receptor agonist, known to induce arteritis due to its vasoconstrictor action, but there is not enough information about MH-induced arteritis. Based on the data obtained under multiple dosing conditions, MH was administered subcutaneously to each rat once daily for 2 days at a dose level of 40 mg/kg/day for MRI assessment. The mesenteric arteries were examined using in vivo MRI at 1 day or 7 days after administration of the final dose and examined histopathologically. On the day after the final dose, high signal intensity region around the artery was observed in animals with minimal perivascular lesions confirmed by histopathology and not observed in an animal without histological changes. On the 7th day after the final dose, no abnormality was observed in histopathological examinations and no high signal intensity regions were observed by MRI in any animal. In conclusion, although further investigation is needed to confirm that high signal intensity is a reliable biomarker for humans, it is suggested that high signal intensity around the artery could be a versatile candidate biomarker with high specificity and sensitivity.

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Brucellosis is a typical zoonosis driven by various risk factors, including environmental ones. The present study aimed to explore the driving effect of environmental factors on human brucellosis in a high incidence rate area, which provides understanding and implications in mitigating disease transmission risk in a multi-system between the human-animal-environment interface for preventing and controlling brucellosis based on the One Health concept. Based on the monthly time series data of human brucellosis and environmental variables, a Seasonal Autoregressive Integrated Moving Average Model with explanatory variables (SARIMAX) was applied to assess the association between environmental indicators and human brucellosis incidence (IHB). The results indicated distinct seasonal fluctuation during the study duration, tending to climb from April to August. Atmospheric pressure, precipitation, relative humidity, mean temperature, sunshine duration, and normalized difference vegetation index significantly drive IHB. Moreover, the well-fitting and predicting capability were performed and assessed in the optimal model was the SARIMAX (0,1,1) (0,1,1)12 model with the normalized difference vegetation index (ß = 0.349, P = 0.036) and mean temperature (ß = 0.133, P = 0.046) lagged in 6 months, and the precipitation lagged in 1 month (ß = -0.090, P = 0.004). Our study suggests the association between environmental risk factors and human brucellosis infection, which can be contributed to mitigating the transmission risk in the environmental drivers in a multi-system interface through comprehensive prevention and intervention strategies based on the One Health concept.

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Objectives: This study aimed to investigate the potential effects of wasp venom (WV) from Vespa magnifica on antithrombosis in rats with inferior vena cava (IVC) thrombosis. Materials and Methods: The thrombosis rat model was established by improving the IVC stenosis, in which rats were subjected to IVC ligation for 75 min. Rats were administered argatroban (IP) or WV (s.c.) for 4 hr after IVC thrombosis. The weight, inhibition rate, and pathological morphology of the thrombosis induced by IVC ligation and the variation in four coagulation parameters, coagulation factors, and CD61+CD62P+ were simultaneously determined in IVC rats. Results: The thrombus formed as a result of IVC ligation was stable. Compared with the control group, the weight of the thrombus was significantly reduced in the argatroban group. Thrombus weight was reduced by treatment with 0.6, 0.2, and 0.05 mg/kg WV, with inhibition rates of 52.19%, 35.32%, and 28.98%, respectively. Inflammatory cells adhered to and infiltrated the vessel wall in the IVC group more than in the sham group. However, the pathological morphology and CD61+CD62P+ of the WV treatment groups tended to be normal. Conclusion: We improved the model of IVC thrombosis to be suitable for evaluation of antithrombotic drugs. Our findings demonstrated that WV could inhibit IVC thrombosis associated with reducing coagulation factors V and CD61+CD62p expression in rats.

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BACKGROUND: Primary central nervous system germinomas of the medulla oblongata are extremely rare and usually have been found in young female Asian patients. The authors present an illustrative case of a patient who presented with severe medullary and posterior cord syndrome, the first South American case published to date, to the authors' knowledge. OBSERVATIONS: Initially, the radiological differential diagnosis did not include this entity. The lesion was located at the obex and exhibited a well-delineated contrast enhancement without hydrocephalus. An emergency decompressive partial resection following functional limits was performed. After histological confirmation, radiotherapy was indicated, with complete remission achieved at a 6-month follow-up. The patient, however, continued to have a severe proprioceptive disorder. The literature review identified 21 other such patients. The mean age for this location was 23 years, with a strong female and Asian origin predilection. All tumors exhibited contrast enhancement, and only one presented with hydrocephalus. LESSONS: In the absence of elevated tumor markers, radiological clues such as a well-delineated, contrast-enhanced lesion arising from the obex, without hydrocephalus, associated with demographic features such as young age, female sex, and Asian heritage, should evoke a high level of suspicion for this diagnosis. Gross total resection must not be attempted, because this tumor is potentially curable with high-dose radiotherapy.

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BACKGROUND: Dentin hypersensitivity (DH) is a common problem in the population that can have a significant impact on the quality of life of those who suffer from the condition. OBJECTIVES: Compare the efficacy of two treatments for DH: Ca/PO4 - /F- varnish (Clinpro White Varnish) and ionomeric sealant (IS) (Clinpro XT Varnish) with a placebo. METHODS: Participants (121) with at least one tooth with visual analogue scale (VAS) score of 4 and above were randomly and blindly allocated to the groups. Treatments were performed by a trained researcher. DH was evaluated by another blind researcher after the treatment and after 1 week, 4 weeks, 3 months and 6 months. After 4 weeks, placebo received the DH treatment with IS; thus, the participants were not assessed after 3 and 6 months. Primary outcome was DH reduction after 4 weeks. Differences in VAS scores in the other time intervals and entire values of VAS were considered secondary outcomes. Comparisons were made among the groups (α = 0.05). RESULTS: IS showed the highest VAS value difference between baseline and 4 weeks (mean ± SD: 3.7 ± 2.2), differing significantly from placebo (2.3 ± 1.7) and Ca/PO4/F- varnish (2.6 ± 2.0). Ca/PO4- /F- varnish did not differ from placebo. In all time intervals, VAS values of all groups were significantly lower than the baseline value, without differences among groups. For the long-term differences in VAS values (3 and 6 months), the IS exhibited significantly higher values than Ca/PO4- /F- varnish. CONCLUSIONS: The IS was the most efficacious product for reducing DH, whereas Ca/PO4- /F- varnish did not differ from placebo. Registered in ClinicalTrials.gov (NCT04591444).

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A method quantifying 16 polycyclic aromatic hydrocarbons (PAHs) in wood vinegars (WVs) obtained from slow pyrolysis of biomass with ultrasonic-assisted liquid-liquid extraction/gas chromatography-mass spectrometry (USALLE/GC-MS) was established. The recovery range was 83-128%, and the relative standard deviations (RSD%) were less than 15% except naphthalene, acenaphthylene and acenaphthene. Acenaphthylene, acenaphthene, fluorene, anthracene, phenanthrene, fluoranthene, and pyrene were observed in all samples and the other 9 compounds, including benzopyrene (B[a]P), were not detected. The concentration of ∑PAHs referred to the sum total of 7 PAHs mentioned above was 22.0-498.3 µg L-1. The PAHs concentration increased with the increasing pyrolysis temperature in bamboo willow WV, pinus sylvestris WV, and corncob WV, while it increased initially, and then decreased with a maximum at 550 °C in rice husk WV. The ∑PAHs concentration increased with a higher heating rate in the white pine WV, while rice husk WV and cornstalk WV showed the opposite trend. The varied condensed aromatic ring number showed that 3-ring PAHs relatively were the main component in all kind WVs. 3-ring PAHs increased with increasing temperatures, while 4-ring PAHs showed an opposite trend in sawdust WV and corncob WVs. A higher cellulose content in sawdust enhanced the reaction of lignin leading to a higher concentration of PAHs than that in straws and leaves. Calculations of the toxicity equivalents of PAHs in WVs indicated that anthracene was the most toxic among the PAHs, and the pinus sylvestris WV had the highest risk of ∑PAHs toxicity in all WVs.

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Plasma membrane transporters play pivotal roles in the import of nutrients, including sugars, amino acids, nucleobases, carboxylic acids, and metal ions, that surround fungal cells. The selective removal of these transporters by endocytosis is one of the most important regulatory mechanisms that ensures a rapid adaptation of cells to the changing environment (e.g., nutrient fluctuations or different stresses). At the heart of this mechanism lies a network of proteins that includes the arrestin-related trafficking adaptors (ARTs) which link the ubiquitin ligase Rsp5 to nutrient transporters and endocytic factors. Transporter conformational changes, as well as dynamic interactions between its cytosolic termini/loops and with lipids of the plasma membrane, are also critical during the endocytic process. Here, we review the current knowledge and recent findings on the molecular mechanisms involved in nutrient transporter endocytosis, both in the budding yeast Saccharomyces cerevisiae and in some species of the filamentous fungus Aspergillus. We elaborate on the physiological importance of tightly regulated endocytosis for cellular fitness under dynamic conditions found in nature and highlight how further understanding and engineering of this process is essential to maximize titer, rate and yield (TRY)-values of engineered cell factories in industrial biotechnological processes.

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BACKGROUND: Interdigestive migrating motor complexes (MMC) produce periodic contractions in the gastrointestinal tract, but the exact mechanism of action still remains unclear. Intramuscular interstitial cells of Cajal (ICC-IM) participate in gastrointestinal hormone and neuromodulation, but the correlation between ICC-IM and MMC is also unclear. We found that xiangbinfang granules (XBF) mediated the phase III contraction of MMC. Here, the effects of XBF on gastric antrum motility in W/W v mice and the effects of ICC-IM on gastric antrum MMC are reported. AIM: To observe the effects of ICC-IM on gastric antrum motility and to establish the mechanism of XBF in promoting gastric antrum motility. METHODS: The density of c-kit-positive ICC myenteric plexus (ICC-MP) and ICC-IM in the antral muscularis of W/W v and wild-type (WT) mice was examined by confocal microscopy. The effects of XBF on gastric antrum slow waves in W/W v and WT mice were recorded by intracellular amplification recording. Micro-strain-gauge force transducers were implanted into the gastric antrum to monitor the MMC and the effect of XBF on gastric antrum motility in conscious W/W v and WT mice. RESULTS: In the gastric antrum of W/W v mice, c-kit immunoreactivity was significantly reduced, and no ICC-IM network was observed. Spontaneous rhythmic slow waves also appeared in the antrum of W/W v mice, but the amplitude of the antrum slow wave decreased significantly in W/W v mice (22.62 ± 2.23 mV vs 2.92 ± 0.52 mV, P < 0.0001). MMCs were found in 7 of the 8 WT mice but no complete MMC cycle was found in W/W v mice. The contractile frequency and amplitude index of the gastric antrum were significantly increased in conscious WT compared to W/W v mice (frequency, 3.53 ± 0.18 cpm vs 1.28 ± 0.12 cpm; amplitude index, 23014.26 ± 1798.65 mV·20 min vs 3782.16 ± 407.13 mV·20 min; P < 0.0001). XBF depolarized smooth muscle cells of the gastric antrum in WT and W/W v mice in a dose-dependent manner. Similarly, the gastric antrum motility in WT mice was significantly increased after treatment with XBF 5 mg (P < 0.05). Atropine (0.1 mg/kg) blocked the enhancement of XBF in WT and W/W v mice completely, while tetrodotoxin (0.05 mg/kg) partially inhibited the enhancement by XBF. CONCLUSION: ICC-IM participates in the regulation of gastric antrum MMC in mice. XBF induces MMC III-like contractions that enhance gastric antrum motility via ICC-IM in mice.

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Coinoculation of plants with mixtures of beneficial microbes sometimes produces synergistic effects. In this study, the effect of soybean coinoculation with the N2-fixing Bradyrhizobium japonicum E109 and the biocontrol fungus Trichoderma harzianum Th5cc was analyzed. Nodulation by E109 was not hampered by Th5cc, which antagonized five out of seven soybean pathogens tested. Furthermore, Th5cc relieved nitrate-inhibition of nodulation, enabling the formation of nodules containing infected cells with bacteroids in the presence of the otherwise inhibitory 10 mM KNO3. Th5cc released micromolar amounts of auxin, and addition of 11 µM indoleacetic acid to soybean plants inoculated with E109 in the absence of Th5cc also induced nodulation in the presence of 10 mM KNO3. Thus, Th5cc may release auxins into the soybean rhizosphere, which hormones might participate in overcoming the nitrate-inhibition of nodulation. Our results suggest that soybean plants coinoculated with these microorganisms might benefit from biocontrol while contributing to soil-nitrogen preservation.

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Currently, testing for immunoglobulin E (IgE) sensitization is the cornerstone of diagnostic evaluation in suspected allergic conditions. This review provides a thorough and updated critical appraisal of the most frequently used diagnostic tests, both in vivo and in vitro. It discusses skin tests, challenges, and serological and cellular in vitro tests, and provides an overview of indications, advantages and disadvantages of each in conditions such as respiratory, food, venom, drug, and occupational allergy. Skin prick testing remains the first line approach in most instances; the added value of serum specific IgE to whole allergen extracts or components, as well as the role of basophil activation tests, is evaluated. Unproven, non-validated, diagnostic tests are also discussed. Throughout the review, the reader must bear in mind the relevance of differentiating between sensitization and allergy; the latter entails not only allergic sensitization, but also clinically relevant symptoms triggered by the culprit allergen.

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The interstitial cells of Cajal associated with the myenteric plexus (ICC-MP) are located in the same area as the myenteric plexus. ICC-MP networks are linked to the generation of electrical pacemaker activity that causes spontaneous gastrointestinal (GI) contractions; however, its role in GI transit is not clear. The aim of this study was to comprehensively investigate the effect of ICC-MP disruption on GI transit in vivo using W/W v mice, partially ICC-deficient model mice. In this study, we measured GI transit using a 13C-octanoic acid breath test, an orally administered dye and a bead expulsion assay. ICC were detected by immunohistochemical staining for c-Kit, a specific marker for ICC. Interestingly, we found that gastric emptying in W/W v mice was normal. We also found that the ability of small intestinal and colonic transit was significantly reduced in W/W v mice. Immunohistochemical staining using whole-mount muscularis samples revealed that c-Kit-positive ICC-MP networks were formed in wild-type mice. In contrast, ICC-MP networks in W/W v mice were maintained only in the gastric antrum and were significantly reduced in the ileum and colon. No significant changes were observed in the nerve structures of the myenteric plexus in W/W v mice. These findings suggest that ICC-MP contribute to GI transit as a powerful driving function in vivo.

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BACKGROUND: Chloroplast biogenesis, a complex process in higher plants, is the key to photoautotrophic growth in plants. White virescent (wv) mutants have been used to unfold the molecular mechanisms underlying the regulation of chloroplast development and chloroplast gene expression in plants. However, most of genes controlling white virescent phenotype still remain unknown. RESULTS: In this study, we identified a temperature- and light intensity-sensitive mutant, named as wv. The content of chlorophyll was dramatically decreased in the immature leaves of wv mutant under the conditions of low temperature and high-light intensity. TEM observation showed that the chloroplasts in the young leaves of wv mutant lacked an organized thylakoid membrane, whereas crescent-shaped chloroplasts with well-developed stromal and stacked grana thylakoids in the mature leaves were developed. Immunoblot analyses suggested that proteins of photosynthetic complexes were decreased substantially in wv mutants. Based on map-based cloning and transgenic analysis, we determined that the wv phenotype was caused by single base mutation in the first intron of WV gene, which encoded a thioredoxin protein with 365 amino acids. qRT-PCR analysis revealed that the expression of WV gene was significantly down-regulated in wv mutant. In addition, knockdown of WV gene through RNAi also resulted in white virescent young leaves, suggesting that the mutation possibly blocks the differentiation of chloroplasts through inhibiting the expression of WV gene. Furthermore, the expression of WV peaked in apical buds and gradually decreased along with the developmental stage, which was consistent with the wv mutant phenotype. Expression analysis of chloroplast-encoded genes by qRT-PCR showed that the wv mutation affected the expression pattern of chloroplast-encoded PEP dependent genes. CONCLUSION: Our results suggested that wv mutant was sensitive to low temperature and light intensity. WV gene was essential for chloroplast differentiation. A single base mutation in the first intron resulted in down-regulation of WV gene expression, which inhibited the expression of chloroplast-encoded genes, thereby blocking chloroplast formation and chlorophyll synthesis.

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PURPOSE: To evaluate the effectiveness of a therapeutic barium enema as a treatment for colonic diverticulum bleeding, by using a standard concentration as a diagnostic examination. METHODS: We retrospectively analyzed 68 cases of the patients admitted to our hospital with colonic diverticular bleeding between October 2012 and September 2017. We evaluated the following items: (1) the presence/absence of a previous history of diverticular bleeding, (2) the use of medications (anticoagulants, nonsteroidal anti-inflammatory drugs, and antiplatelet drugs), (3) the location of bleeding, (4) the presence/absence of previous treatment and the result, (5) the time between bleeding and the beginning of the barium enema, (6) procedural success, (7) the clinical success of the initial hemostasis, (8) the clinical success of preventing recurrence, and (9) complications such as perforation and diverticulitis associated with this procedure. RESULTS: Four patients (three men and one woman; age range 60-85 years; median age 76 years) who underwent therapeutic barium enema with a concentration equivalent for diagnostic purpose (78 w/v%) were included. The follow-up period ranged from 11 to 12 months (median 12 months). All three patients who received a barium enema for initial hemostasis were successfully treated. All four patients remained free from recurrence during the follow-up period. There was no complication due to barium in this series. CONCLUSION: Although we had no statistical evidence, a therapeutic barium enema with a standard concentration as a diagnostic examination may be effective for both the initial hemostasis and preventing the recurrence of colonic diverticular bleeding without complications.

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BACKGROUND: Whole-ventricular radiotherapy (WV-RT) followed by a boost to the tumor bed (WV-RT/TB) is recommended for intracranial germ cell tumors (IGCT). As the critical brain areas are mainly in the target volume vicinity, it is unclear if protons indeed substantially spare neurofunctional organs at risk (NOAR). Therefore, a dosimetric comparison study of WV-RT/TB was conducted to assess whether proton or photon radiotherapy achieves better NOAR sparing. METHODS: Eleven children with GCT received 24 Gy(RBE) WV-RT and a boost up to 40 Gy(RBE) in 25 fractions of 1.6 Gy(RBE) with pencil beam scanning proton therapy (PBS-PT). Intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans were generated for these patients. NOAR were delineated and treatment plans were compared for target volume coverage (TVC), homogeneity index (HI), inhomogeneity coefficient (IC) and (N)OAR sparing. RESULTS: TVC was comparable for all three modalities. Compared to IMRT and VMAT, PBS-PT showed statistically significant optimized IC, as well as dose reduction, among others, in mean and integral dose to the: normal brain (-35.2%, -32.7%; -35.2%, -33.0%, respectively), cerebellum (-53.7%, -33.1%; -53.6%, -32.7%) and right temporal lobe (-14.5%, -31.9%; -14.7%, -29.9%). The Willis' circle was better protected with PBS-PT than IMRT (-7.1%; -7.8%). The left hippocampus sparing was higher with IMRT. Compared to VMAT, the dose to the hippocampi, amygdalae and temporal lobes was significantly decreased in the IMRT plans. CONCLUSIONS: Dosimetric comparison of WV-RT/TB in IGCT suggests PBS-PT's advantage over photons in conformality and NOAR sparing, whereas IMRT's superiority over VMAT, thus potentially minimizing long-term sequelae.

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BACKGROUND AND AIMS: The use of woody crops for Quad-level (approx. 1 × 1018 J) energy production will require marginal agricultural lands that experience recurrent periods of water stress. Populus species have the capacity to increase dehydration tolerance by lowering osmotic potential via osmotic adjustment. The aim of this study was to investigate how the inherent genetic potential of a Populus clone to respond to drought interacts with the nature of the drought to determine the degree of biochemical response. METHODS: A greenhouse drought stress study was conducted on Populus deltoides 'WV94' and the resulting metabolite profiles of leaves were determined by gas chromatography-mass spectrometry following trimethylsilylation for plants subjected to cyclic mild (-0.5 MPa pre-dawn leaf water potential) drought vs. cyclic severe (-1.26 MPa) drought in contrast to well-watered controls (-0.1 MPa) after two or four drought cycles, and in contrast to plants subjected to acute drought, where plants were desiccated for up to 8 d. KEY RESULTS: The nature of drought (cyclic vs. acute), frequency of drought (number of cycles) and the severity of drought (mild vs. severe) all dictated the degree of osmotic adjustment and the nature of the organic solutes that accumulated. Whereas cyclic drought induced the largest responses in primary metabolism (soluble sugars, organic acids and amino acids), acute onset of prolonged drought induced the greatest osmotic adjustment and largest responses in secondary metabolism, especially populosides (hydroxycinnamic acid conjugates of salicin). CONCLUSIONS: The differential adaptive metabolite responses in cyclic vs. acute drought suggest that stress acclimation occurs via primary metabolism in response to cyclic drought, whereas expanded metabolic plasticity occurs via secondary metabolism following severe, acute drought. The shift in carbon partitioning to aromatic metabolism with the production of a diverse suite of higher order salicylates lowers osmotic potential and increases the probability of post-stress recovery.

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Complex optical properties, such as non-pigment suspension and colored dissolved organic matter (CDOM), make it difficult to achieve accurate estimations of remotely sensed chlorophyll a (Chla) content of inland turbidity. Recent attempts have been made to estimate Chla based on red and near-infrared regions where non-pigment suspension and CDOM have little effect on water reflectance. The objective of this study is to validate the applicability of WV-2 imagery with existing effective estimation methods from MERIS when estimating Chla content in inland turbidity waters. The correlation analysis of measured Chla content and WV-2 imagery bands shows that the Chla sensitive bands of WV-2 are red edge, NIR 1, and NIR 2. The coastal band is designed for seawater Chla detection. However, the high correlation with turbidity data and low correlation with Chla made coastal band unsuitable for estimating Chla in inland waters. The high-resolution water body images were extracted by combining the spectral products (NDWI) with the spatial morphological products (sobel edge detection). The estimation results show that the accuracy of the single band and NDCI is not as good as the two-band method, three-band method, stepwise regression algorithm (SRA) and support vector machines (SVM). The SVM estimation accuracy was the highest with an R2, RMSE, and URMSE of 0.8387, 0.4714, and 19.11%, respectively. This study demonstrates that the two-band and three-band methods are effective for estimating Chla in inland water for WV-2 imagery. As a high-precision estimation method, SVM has great potential for inland turbidity water Chla estimation.

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Regulation of colonic motility depends on the integrity of enteric inhibitory neurotransmission mediated by nitric oxide (NO), purine neurotransmitters, and neuropeptides. Intramuscular interstitial cells of Cajal (ICC-IM) and platelet-derived growth factor receptor-α-positive (PDGFRα+) cells are involved in generating responses to NO and purine neurotransmitters, respectively. Previous studies have suggested a decreased nitrergic and increased purinergic neurotransmission in KitW/KitW-v (W/Wv ) mice that display lesions in ICC-IM along the gastrointestinal tract. However, contributions of NO to these phenotypes have not been evaluated. We used small-chamber superfusion assays and HPLC to measure the spontaneous and electrical field stimulation (EFS)-evoked release of nicotinamide adenine dinucleotide (NAD+)/ADP-ribose, uridine adenosine tetraphosphate (Up4A), adenosine 5'-triphosphate (ATP), and metabolites from the tunica muscularis of human, monkey, and murine colons and circular muscle of monkey colon, and we tested drugs that modulate NO levels or blocked NO receptors. NO inhibited EFS-evoked release of purines in the colon via presynaptic neuromodulation. Colons from W/Wv, Nos1-/- , and Prkg1-/- mice displayed augmented neural release of purines that was likely due to altered nitrergic neuromodulation. Colons from W/Wv mice demonstrated decreased nitrergic and increased purinergic relaxations in response to nerve stimulation. W/Wv mouse colons demonstrated reduced Nos1 expression and reduced NO release. Our results suggest that enhanced purinergic neurotransmission may compensate for the loss of nitrergic neurotransmission in muscles with partial loss of ICC. The interactions between nitrergic and purinergic neurotransmission in the colon provide novel insight into the role of neurotransmitters and effector cells in the neural regulation of gastrointestinal motility.NEW & NOTEWORTHY This is the first study investigating the role of nitric oxide (NO) and intramuscular interstitial cells of Cajal (ICC-IM) in modulating neural release of purines in colon. We found that NO inhibited release of purines in human, monkey, and murine colons and that colons from KitW/KitW-v (W/Wv ) mice, which present with partial loss of ICC-IM, demonstrated augmented neural release of purines. Interactions between nitrergic and purinergic neurotransmission may affect motility in disease conditions with ICC-IM deficiencies.

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