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In this paper we examine variation of polar cap potential (PCP) during two storm events that occurred on 24 November 2001 and 24 August 2005 using Lyon‐Fedder‐Mobarry (LFM) and Block‐Adaptive‐Tree‐Solarwind_Roe‐Upwind‐Scheme (BATS‐R‐US) simulations and compare it to Weimer model. These events were simulated for zero, pure By, pure Bz, and full IMF conditions separately, and the PCP obtained were compared with the zero IMF PCP value as a baseline (viscous) potential. For southward IMF, PCP is defined as sum of reconnection and viscous, whereas for northward IMF, it is peak to peak potential, which either will be viscous potential or reconnection potential, whichever is larger. Both events were simulated for a constant ionospheric conductivity of 5 mhos and the variation of PCP was found to be consistent with previous literatures. Furthermore, we found that BATS‐R‐US PCP fluctuated similar to LFM PCP for most parts although their PCP values did not exactly match. We observed that BATS‐R‐US PCP also goes below viscous value for northward IMF condition, something which was observed previously in LFM simulation only. We also found that BATS‐R‐US PCP is more sensitive to smaller fluctuation of IMF compared to LFM. For 24 August 2005 event, we found the PCP reach up to 550 and 440 kV and the viscous potential reached up to 120 and 110 kV for BATS‐R‐US and LFM, respectively. Similarly, for 24 November 2001 event PCP reached up to 800 and 400 kV and viscous potential reached up to 300 and 200 kV, respectively, for BATS‐R‐US and LFM. Key Points: BATS‐R‐US is found to be overall sensitive to velocity, density, and IMF fluctuation compared to LFM except for ByWe found that BATS‐R‐US PCP also varied similar to LFM PCP for most parts [ABSTRACT FROM AUTHOR]

Inadequate oxygen concentration in the root zone is a constraint to plant performance particularly in heavy, compacted and/or saline soils. Sub-surface drip irrigation (SDI) offers a means of increasing oxygen to plant roots in such soils, provided irrigation water can be hyper-aerated or oxygenated. Hydrogen peroxide (HP) at the rate of 5 litre ha[sup-1] at the end of each irrigation cycle was injected through SDI tape to a field-grown zucchini (courgette) crop (Cucurbita pepo) on a saturated heavy clay soil in Queensland, Australia. Fruit yield, number and shoot weight increased by 25%, 29% and 24% respectively due to HP treatment compared to the control. Two pot experiments with vegetable soybean (Glycine max) and cotton (Gossypium hirsutum) compared the effectiveness of HP and air injection using a Mazzei™ air injector (a venturi), throughout the irrigation cycle in raising crop yield in a heavy clay soil kept at saturation or just under field capacity. Fresh pod yield of vegetable soybean increased by 82-96% in aeration treatments compared with the control. The yield increase was associated with more pods per plant and greater mean pod weight. Significantly higher above ground biomass and light interception were evident with aeration, irrespective of soil water treatment. Similarly cotton lint yield increased by 14-28% in aeration treatments compared with the control. The higher lint yield was associated with more squares and bolls per plant which accompanied greater above ground biomass and an increase in root mass, root length and soil respiration. Air injection and HP effected greater water use, but also brought about an enhancement of water use efficiency (WUE) for pod and lint yield, and increased leaf photosynthetic rate in both species but had no effect on transpiration rate and stomatal conductance per unit leaf area. Aeration-induced enhanced root function was arguably responsible for greater fruit set and yield in all... [ABSTRACT FROM AUTHOR]

Background The loss of endothelial integrity increases the risk of intracerebral hemorrhage during ischemic stroke. Adjunct therapeutic targets for reperfusion in ischemic stroke are in need to prevent blood-brain barrier disruption. Recently, we have shown that endothelial permeability is mediated by lysophosphatidic acid (LPA), but the role of autotaxin, which produces LPA, remains unclear in stroke. We investigate whether autotaxin/LPA axis regulates blood-brain barrier integrity after cerebral ischemia. Methods and Results Ischemic stroke was induced in mice by middle cerebral artery occlusion for 90 minutes, followed by 24-hour reperfusion. The therapeutic efficacy of autotaxin/LPA receptor blockade was evaluated using triphenyl tetrazolium chloride staining, Evans blue permeability, infrared imaging, mass spectrometry, and XF24 analyzer to evaluate blood-brain barrier integrity, autotaxin activity, and mitochondrial bioenergetics. In our mouse model of ischemic stroke, the mRNA levels of autotaxin were elevated 1.7-fold following the cerebral ischemia and reperfusion (I/R) group compared with the sham. The enzymatic activity of autotaxin was augmented by 4-fold in the I/R group compared with the sham. Plasma and brain tissues in I/R group showed elevated LPA levels. The I/R group also demonstrated mitochondrial dysfunction, as evidenced by decreased ( P <0.01) basal oxygen consumption rate, mitochondrial ATP production, and spare respiratory capacity. Treatment with autotaxin inhibitors (HA130 or PF8380) or autotaxin/LPA receptor inhibitor (BrP-LPA) rescued endothelial permeability and mitochondrial dysfunction in I/R group. Conclusions Autotaxin-LPA signaling blockade attenuates blood-brain barrier disruption and mitochondrial function following I/R, suggesting targeting this axis could be a new therapeutic approach toward treating ischemic stroke.

Background: Pancreatoblastoma (PBL) is a rare malignant pancreatic tumor seen predominantly in childhood, and its cytologic diagnosis remains challenging., Methods: Twelve fine-needle-aspirations from 11 adults were analyzed., Results: In total, 6 men and 5 women (median age, 45 years; age range, 32-60 years) had tumors measuring a median 5.6 cm (range, 2.5-12 cm) located in the pancreatic head (n = 7) or tail (n = 4), including 3 with familial adenomatous polyposis (FAP)/FAP-related syndromes and 4 with metastasis at diagnosis. The median follow-up was 39.8 months (range, 0.8-348 months), and 5 patients died of disease. The original cytology diagnoses were: PBL (n = 2), neuroendocrine neoplasm (n = 2), poorly differentiated neuroendocrine carcinoma (n = 2), well differentiated neuroendocrine tumor (n = 1), poorly differentiated carcinoma (n = 2), "positive for malignancy" (n = 1), acinar cell carcinoma (n = 1), and epithelioid neoplasm with endocrine and acinar differentiation versus PBL (n = 1). Universal cytopathologic findings included hypercellularity; 3-dimensional clusters; and single, monotonous, blast-like cells that were from 1.5 to 2.0 times the size of red blood cells with high nuclear-to-cytoplasmic ratio, fine chromatin, small, distinct nucleoli, and a resemblance to well differentiated neuroendocrine tumor and poorly differentiated neuroendocrine carcinoma. Branching pseudopapillae (n = 7) and grooved nuclei (n = 3) raised the differential diagnosis of solid-pseudopapillary neoplasm, but with more atypia. Uncommon features included pleomorphism (n = 4) and numerous mitoses (n = 1). Squamoid morules were seen on smears (n = 5) or cell blocks (n = 6) in 70% of patients and were characterized by epithelioid cells with elongated, streaming nuclei, fine chromatin, absent nucleoli, and positive nuclear β-catenin (n = 6 of 8). The median Ki-67 index was 21% (range, 2%-70%), and neuroendocrine marker expression was common (100%), but acinar markers were variable (63%)., Conclusions: A combination of cytologic findings in PBL, including a predominant population of primitive blast-like cells, subtle squamoid morules, frequent neuroendocrine and variable acinar phenotype, should facilitate accurate cytologic diagnosis and distinction from common mimics., (© 2019 American Cancer Society.)

Background: Hepatocellular carcinoma (HCC) rarely involves the biliary tree and may be inadvertently sampled on bile duct brushings (BDBs)., Methods: The pathology archives of 5 institutions were searched for BDBs with HCC involvement., Results: A total of 17 BDBs from 14 patients were obtained. There was a male:female ratio of 6:1; the median age of the patients was 59.5 years (range, 22-80 years). The median hepatic tumor size was 6.2 cm (range, 2.2-13.0 cm). HCC risk factors included viral hepatitis (5 patients), cirrhosis (5 patients), hemochromatosis (1 patient), and alcoholic steatohepatitis (1 patient). Jaundice with elevated bilirubin, liver enzymes, and α-fetoprotein was common. Endoscopic retrograde cholangiopancreatography demonstrated bile duct dilatation, polypoid intraductal masses (5 samples), clots/debris (2 samples), or strictures (4 samples). All BDBs had single and clustered large cells with naked atypical nuclei, granular cytoplasm, high nuclear/cytoplasmic ratios, and nuclei with prominent macronucleoli. Less common findings included clear/microvesicular cytoplasm (35%), papillae (29%), and anisonucleosis (35%). Classic HCC features (widened trabeculae [35%], endothelial wrapping [24%], multinucleation [24%], and cytoplasmic bile pigment [35%]) were uncommon. A total of 11 BDBs were diagnosed as malignant (10 with HCC and 1 with cholangiocarcinoma), 2 were diagnosed as atypical, and 1 BDB was diagnosed as negative; approximately two-thirds were found to have polysomy on fluorescence in situ hybridization. Approximately 71% of patients died of disease at a median of 3.5 months., Conclusions: HCC may extend into the intrahepatic and/or extrahepatic biliary tree, causing masses and/or strictures that may be sampled on BDB. Although cytologically malignant, the classic features of HCC are uncommon, which can cause misdiagnosis. Cytopathologists should be mindful of this differential when evaluating BDBs, particularly when concomitant liver masses and/or HCC risk factors are present. Because of the associated high mortality and rapid rate of death, its presence should be conveyed clearly in pathology reports., (© 2019 American Cancer Society.)

The authors examined the associations between coronary artery calcification and a family history of premature coronary heart disease in either first-degree (immediate family) or second-degree (grandparents, aunts, uncles) relatives in 1619 asymptomatic healthy men ages 40-50 years. The prevalence of any coronary artery calcification was 19.3% in participants (n=1102) with no family history, 26.6% in those with a first-degree family history (n=203; 12.5%), 26.5% in those with a second-degree family history (n=215, 13.3%), and 30.3% with both (n=99, 6.1%, p=0.003). After controlling for the Framingham risk score, body mass index, and ethnicity, all categories of family history were significant predictors of coronary artery calcification. The odds ratios for coronary artery calcification associated with a first- (1.49; p=0.026) and second-degree (1.41; p=0.049) family history of coronary heart disease were similar. Clinical coronary risk assessments should broadly include an assessment of premature coronary heart disease in both first- and second-degree relatives.

Acropigmentation of Dohi is a rare acropigmentary disorder. We report two cases of reticulate acropigmentation of Dohi from Nepal. To the best of our knowledge, these two cases represent the first case reports from Nepal.