What drives the increased phytoplankton biomass in the Arabian Sea?

The seasonal variability of phytoplankton biomass in the Arabian Sea, though a well researched topic, its inter-annual variability is less explored and understood. Analysis of the satellite-derived chlorophyll pigment concentration in the Arabian Sea during 1997–2007 showed a weak increasing trend. Contrary to the earlier hypothesis, our analysis showed that this increased phytoplankton biomass was not driven by the strengthening winds during summer monsoon. In fact, the basin-averaged chlorophyll concentrations during summer monsoon tend to decline, whereas those in September–October and during the winter monsoon showed an increasing trend. Based on the analysis of wind and aerosol optical thickness data, we attribute the increased phytoplankton biomass during September–October to dust-induced iron fertilization when there is sufficient buildup of nitrate in the upper ocean. During winter, the enhanced evaporative cooling under the strengthening winds led to the increased convective mixing. Subsequent supply of subsurface nutrients to the euphotic zone coupled with the increased dust delivery support the observed increase in phytoplankton biomass during winter

Response of the Arabian Sea to global warming and associated regional climate shift

The response of the Arabian Sea to global warming is the disruption in the natural decadal cycle in the sea surface temperature (SST) after 1995, followed by a secular warming. The Arabian Sea is experiencing a regional climate-shift after 1995, which is accompanied by a five fold increase in the occurrence of “most intense cyclones”. Signatures of this climate-shift are also perceptible over the adjacent landmass of India as: (1) progressively warmer winters, and (2) decreased decadal monsoon rainfall. The warmer winters are associated with a 16-fold decrease in the decadal wheat production after 1995, while the decreased decadal rainfall was accompanied by a decline of vegetation cover and increased occurrence of heat spells. We propose that in addition to the oceanic thermal inertia, the upwelling-driven cooling provided a mechanism that offset the CO2-driven SST increase in the Arabian Sea until 1995

Synthesis and structure characterization of [Co(H2O)2(DMSO)2(4-nba)]4-nba (DMSO = dimethylsulfoxide; 4-nba = 4-nitrobenzoate)

51-56Dissolution of a fine powder obtained by mechanochemical grinding of cobaltous carbonate with 4-nitrobenzoic acid (4-nbaH) in hot dimethylsulfoxide (DMSO) followed by slow evaporation of the solvent resulted in the formation of cis-diaquabis(dimethylsul-foxide)4-nitrobenzoatocobalt(II) 4-nitrobenzoate 1 in good yield. The title compound [Co(H2O)2(DMSO)2(4-nba)]4-nba 1 crystallizes in the centrosymmetric monoclinic P21/c space group. The structure of 1 consists of two crystallographically independent Co(II) ions. Each unique cobalt exhibits octahedral geometry and is bonded to a pair of terminal aqua ligands situated cis to each other and a bidentate 4-nba ligand which form the square base of the octahedron. A pair of DMSO ligands disposed trans to each other complete the hexa coordination around the central metal. The [Co(H2O)2(DMSO)2 (4-nba)]+ cations and the 4-nba anions are interlinked with the aid of several weak H-bonding interactions. A comparative study of several 4-nitrobenzoate compounds of cobalt is described

Comminuted olecranon fractures: locking compression plate fixation verses conventional plate fixation

Background: A variable consensus exists on the optimal management strategies for olecranon fractures. Though the mechanical properties of the conventional plates and the locking plates used show no difference, pre-contoured locking plates provide a significant advantage over non-locking plates in unstable fractures. The aim of the study was to compare clinical and radiological outcomes in the management of the comminute olecranon fractures by anatomically pre-contoured locking compression plates and the conventional plates.Methods: The present study was a prospective study of 50 patients with comminuted olecranon fracture, with 25 patients each randomized into two groups, those that underwent fixation of the fracture using a pre-contoured locking compression plate (group LCP) and those fixed using a conventional plate (3.5 mm reconstruction plate) (group CP). Patients were followed up to 1 year with functional outcome assessed at each follow-up with Mayo elbow performance score.Results: The mean MEPS (LCP vs CP) at 1.5 (47 vs. 43.4) and 3 (67.4 vs 61.6) months follow up showed a statistically significant difference between the two groups, but the difference was not significant at 6 (86.4 vs 85.6) and 12 (88.4 vs 87) months. The time to union (4.3 months vs 5.0 months) was not significantly different between the groups. There were 11 complications in group LCP and 12 complications in group CP.Conclusions: In the present study, we suggest that the use of a pre-contoured locking compression plate provides better outcomes at earlier periods as compared to the conventional plate; thus, returning the patient to normal function at the earliest

Vitamin C supplementation as adjuvant analgesic therapy in post-operative pain management in patients undergoing surgical decompression in a case of prolapsed intervertebral disc

Background: The management of postoperative pain has been a major challenge for the operating surgeons. Vitamin C has shown analgesic effects in specific clinical conditions, reducing patient suffering and improving the quality of life. The objective of this study was to evaluate the efficacy of vitamin C as an adjuvant in postoperative pain management and its effect on analgesia requirements in patients undergoing spinal decompression surgery.Methods: The present study was a prospective study of 50 patients aged 30-60 years with low back pain due to prolapsed intervertebral disc requiring surgical decompression, conducted in a tertiary care institute from 2018 to 2020. All patients underwent open discectomy. 25 patients each were randomized into two groups, those that were given vitamin c supplementation (group A) and those that weren't (group B). The patients were then followed up 1st, 2nd, 4th, and 6th week and the pain was graded at each follow-up according to the NRS scale. The total amount of diclofenac sodium consumed in the 6 weeks was calculated.Results: The mean NRS (A vs B) at 2 (2.68 vs 3.56) and 4 (0.88 vs 1.48) weeks follow-up showed a statistically significant difference between the two groups, but the difference was not significant at 6 (0.16 vs 0.36) weeks follow up. The difference in the consumption of analgesic (3.56 vs 5.46) at 6 weeks was statistically significant.Conclusions: In this clinical outcome-based study, we suggest that for postoperative pain management, vitamin C acts as an efficacious adjuvant with a dose-sparing effect on the consumption of analgesics

Rapid Screening of Ellagitannins in Natural Sources via Targeted Reporter Ion Triggered Tandem Mass Spectrometry

Complex biomolecules present in their natural sources have been difficult to analyze using traditional analytical approaches. Ultrahigh-performance liquid chromatography (UHPLC-MS/MS) methods have the potential to enhance the discovery of a less well characterized and challenging class of biomolecules in plants, the ellagitannins. We present an approach that allows for the screening of ellagitannins by employing higher energy collision dissociation (HCD) to generate reporter ions for classification and collision-induced dissociation (CID) to generate unique fragmentation spectra for isomeric variants of previously unreported species. Ellagitannin anions efficiently form three characteristic reporter ions after HCD fragmentation that allows for the classification of unknown precursors that we call targeted reporter ion triggering (TRT). We demonstrate how a tandem HCD-CID experiment might be used to screen natural sources using UHPLC-MS/MS by application of 22 method conditions from which an optimized data-dependent acquisition (DDA) emerged. The method was verified not to yield false-positive results in complex plant matrices. We were able to identify 154 non-isomeric ellagitannins from strawberry leaves, which is 17 times higher than previously reported in the same matrix. The systematic inclusion of CID spectra for isomers of each species classified as an ellagitannin has never been possible before the development of this approach

Case report: intra-tendinous ganglion of the anterior cruciate ligament in a young footballer

A 20-year-old male medical student and keen rugby player presented with a 12-month history of progressively worsening right knee pain and stiffness with no history of trauma. Clinical examination revealed effusion and posterior knee pain exacerbated by end range movement and an extension lag of 15 degrees. Physiotherapy to improve the range of motion proved unsuccessful. Magnetic resonance imaging showed that the ACL was grossly thickened and displaced by material reported as mucoid in nature. There were also areas of focally high signal in relation to its tibial attachment and intra osseous small cysts. Arthroscopic examination revealed a ganglion related to the tibial attachment of the ACL and gross thickening and discoloration of the ACL. Biopsies were taken showing foci of mucoid degeneration in the ACL. A large intra-ACL mass of brownish coloured tissue was excised arthroscopically. Already at 2 weeks follow up the patient had greatly improved range of movement and was pain free. However, upon returning to rugby, joint instability was noticed and a tear of the ACL was confirmed. This rare clinical condition can be diagnosed with MRI and arthroscopic debridement effectively relieves symptoms. This case report illustrates that augmentation or reconstruction may end up being the definitive treatment for athletes. It may also offer some support to the argument that mucoid degeneration and ganglion cyst formation share a similar pathogenesis to intra-osseous cyst formation

Curriculum Learning for Reinforcement Learning Domains: A Framework and Survey

Reinforcement learning (RL) is a popular paradigm for addressing sequential decision tasks in which the agent has only limited environmental feedback. Despite many advances over the past three decades, learning in many domains still requires a large amount of interaction with the environment, which can be prohibitively expensive in realistic scenarios. To address this problem, transfer learning has been applied to reinforcement learning such that experience gained in one task can be leveraged when starting to learn the next, harder task. More recently, several lines of research have explored how tasks, or data samples themselves, can be sequenced into a curriculum for the purpose of learning a problem that may otherwise be too difficult to learn from scratch. In this article, we present a framework for curriculum learning (CL) in reinforcement learning, and use it to survey and classify existing CL methods in terms of their assumptions, capabilities, and goals. Finally, we use our framework to find open problems and suggest directions for future RL curriculum learning research

Organische Überzüge auf Eisenoxiden und Chloriten

Die Adsorption von organischer Substanz an Bodenminerale kann die Eigenschaften der Mineraloberfläche und damit deren Reaktivität vollständig verändern. In welchem Ausmaß Mineraloberflächen im Boden mit organischer Substanz bedeckt sind und woraus diese neuen organischen Oberflächen zusammengesetzt sind ist Gegenstand unserer Untersuchungen. Das Vorhandensein und die Zusammensetzung organischer Überzüge auf Fe-Oxiden (und falls vorhanden Tonmineralen) wurde mit Rasterkraftmikroskopie (AFM) und räumlich aufgelöster Röntgenabsorptionsspektroskopie (STXM mit NEXAFS an der C K-Kante und der Fe L-Kante) analysiert. Die untersuchten Fe-Oxide stammten aus drei Systemen mit unterschiedlichem organischem Ausgangsmaterial: (1) synthetische Goethite, die mit Biofilmen in Kontakt gebracht wurden, (2) natürliche Fe-Oxide, die in einem Quellaustritt, vermutlich unter starker mikrobieller Beteiligung, ausgefällt wurden und (3) Goethit-dominierte natürliche Fe-Oxide aus dem Go-Horizont eines Brauneisengleys. Unsere Auswertung ist noch nicht abgeschlossen. Erste Ergebnisse zeigen, dass das mit den Fe-Oxiden assoziierte organische Material aus den drei Milieus sehr unterschiedlich zusammengesetzt ist: Überzüge auf den Oxiden aus Biofilmen werden von Proteinen und Alkyl C dominiert. Die Überzüge auf den Fe-Oxiden aus der Quelle sind im Vergleich dazu wesentlich reicher an Aryl C und O-Alkyl C, jedoch ärmer an Alkyl C. Die Überzüge der Fe-Oxide aus dem Brauneisengley sind dagegen reich an Alkyl C und Carbonyl C. Im Brauneisengley sind zusätzlich zu den Fe-Oxiden auch Chlorite vorhanden. Auf diesen ist das NEXAFS-C-Signal wesentlich schwächer als auf den Oxiden. Gleichzeitig detektiert das AFM auf den Chloriten eine deutlich höhere Adhäsion zwischen Spitze und Mineral als auf den Fe-Oxiden. Wir nehmen daher an, dass die Chlorite weniger organisches Material binden als die Fe-Oxide. In den kommenden Monaten werden wir uns der räumlichen Homogenität bzw. Heterogenität der Überzüge widmen und die räumliche Verteilung von C, N, P und S in den Überzügen per NanoSIMS beschreiben

Terahertz Security Image Quality Assessment by No-reference Model Observers

To provide the possibility of developing objective image quality assessment (IQA) algorithms for THz security images, we constructed the THz security image database (THSID) including a total of 181 THz security images with the resolution of 127*380. The main distortion types in THz security images were first analyzed for the design of subjective evaluation criteria to acquire the mean opinion scores. Subsequently, the existing no-reference IQA algorithms, which were 5 opinion-aware approaches viz., NFERM, GMLF, DIIVINE, BRISQUE and BLIINDS2, and 8 opinion-unaware approaches viz., QAC, SISBLIM, NIQE, FISBLIM, CPBD, S3 and Fish_bb, were executed for the evaluation of the THz security image quality. The statistical results demonstrated the superiority of Fish_bb over the other testing IQA approaches for assessing the THz image quality with PLCC (SROCC) values of 0.8925 (-0.8706), and with RMSE value of 0.3993. The linear regression analysis and Bland-Altman plot further verified that the Fish__bb could substitute for the subjective IQA. Nonetheless, for the classification of THz security images, we tended to use S3 as a criterion for ranking THz security image grades because of the relatively low false positive rate in classifying bad THz image quality into acceptable category (24.69%). Interestingly, due to the specific property of THz image, the average pixel intensity gave the best performance than the above complicated IQA algorithms, with the PLCC, SROCC and RMSE of 0.9001, -0.8800 and 0.3857, respectively. This study will help the users such as researchers or security staffs to obtain the THz security images of good quality. Currently, our research group is attempting to make this research more comprehensive.Comment: 13 pages, 8 figures, 4 table