Influence of catalytic systems on the synthesis of (dis)entangled UHMWPE and its implications on mechanical properties

Two different catalysts (bis[N-(3-tert-butylsalicylidene)-pentafluoroanilinato] titanium (IV) dichloride and [1-(8-quinolyl)indenyl] chromium (III) dichloride catalysts) activated with aluminoxane based co-catalysts (MAO, PMAO, MMAO12 and MMAO3A) have been evaluated in the polymerisation of ethylene leading to UHMWPE having a reduced number of entanglements between the chains. The effect of a co-catalyst modifier (BHT) on the catalytic systems and the resulting polymers is also addressed. Both catalysts are capable to promote the synthesis of UHMWPE having a reduced amount of entanglements in the conditions used. Uniaxial solid-state deformation of UHMWPE samples of different molar masses have been evaluated and related with the entanglement state of the polymers synthesised. A clear relationship between some mechanical properties and the molar mass/entanglement density of the polymers synthesised has been found

(De)motivating factors among TESOL professionals writing in English for publication from South America

While the literature has examined the experiences and attitudes of TESOL (Teaching English to Speakers of Other Languages) professionals toward writing in English for publication in terms of material, environmental, and political conditions as well as (non)discursive challenges, little is known about the (de)motivating factors underpinning their drive to publish in English, particularly in South America. This study explores the (de)motivation of 522 TESOL professionals in South America to write for publication in English. The study adopted a sequential mixed-methods design that consisted of an online survey followed by 20 individual interviews with purposefully sampled participants. Findings show that, despite personal and social-contextual challenges, the participants were driven by altruism, impact, and self-efficacy

Contribution to the phytosociological characterization of the forest vegetation of the Sicani Mountains (inland of north-western Sicily).

The results of a phytosociological survey on the main forest vegetation aspects of the Sicani Mountains (inland of north-western Sicily), in turn included in the homonymous Regional Park recently established, are presented. This expansive territory (43,687 hectares), located between the Agrigento and Palermo provinces, is mainly composed by carbonate and silico-carbonate formations of the Sicani Units, whose highest peaks are represented by Mount Cammarata (1578 m a.s.l.), Mount delle Rose (1436 m), Pizzo Cangialoso (1420 m) and Mount Pernice (1393 m). Under the bioclimatic aspect, the area falls within the thermo- and supramediterranean belts, with ombrotype ranging from upper dry (annual average rainfall of about 550 mm) in the southern and western slopes, to upper subhumid (annual average rainfall of 800-1000 mm) – sometimes tending towards the wet – in the cacuminal part of the aforecited elevations. Many plant communities were identified and surveyed, several of which are described as new syntaxa; in particular they are some maquis associations [1) Rhamno alaterni-Euphorbietum dendroidis Géhu & Biondi 1997, with the subassociations typicum, phlomidetosum fruticosae (Brullo & Marcenò 1985) comb. nov., rhamnetosum oleoidis (Brullo & Marcenò 1985) comb. nov., celtidetosum aetnensis (Brullo & Marcenò 1985) comb. nov., euphorbietosum bivonae (Gianguzzi, Ilardi & Raimondo 1996) comb. nov.; 2) Ampelodesmo mauritanici-Juniperetum turbinatae Gianguzzi et al. 2012, with the subass. cistetosum cretici Gianguzzi et al. 2012; 3) Asparago albi-Artemisietum arborescentis ass. nova; 4) Euphorbio characiae-Anagyridetum phoetidis ass. nova, with the subass. asparagetosum albae subass.nova and loniceretosum implexae subass. nova; 5) Pistacio terebinthi-Celtidetum aetnensis Gianguzzi, Cusimano & Romano 2014, subass. typicum and phlomidetosum fruticosae Gianguzzi, Cusimano & Romano 2014)], a laurel oak community [Acantho mollis-Lauretum nobilis Gianguzzi, D’Amico & Romano 2010], some holm oak communities [7) Ampelodesmo mauritanici-Quercetum ilicis ass. nova hoc loco, with the subass.typicum subass. nova and viburnetosum tini subass. nova); 8) Sorbo torminalis-Quercetum ilicis ass. nova], some deciduous oak communities with Quercus virgiliana [9) Oleo oleaster-Quercetum virgilianae Brullo 1984; 10) Sorbo torminalis-Quercetum virgilianae Brullo, Minissale, Signorello & Spampinato 1996], a maple community with Acer pseudoplatanus [11) Sorbo graecae-Aceretum pseudoplatani Gianguzzi & La Mantia 2004], a riparian community with Salix sp. pl. [12) Salicetum albo-pedicellatae Brullo & Spampinato 1990] and some shrubby mantles [13) Hyperico majoris-Rubetum ulmifolii ass. nova; 14) Roso corymbiferae-Rubetum ulmifolii ass. nova; 15) Euphorbio characiae-Prunetum spinosae ass. nova; 16) Roso siculae-Prunetum spinosae ass. nova; 17) Crataegetum laciniatae Brullo & Marcenò in Brullo 1984]. A new alliance with a Tyrrhenian centre of gravitation (Asparago acutifolii-Laurion nobilis, in turn ascribed to the class Quercetea ilicis and to the order Quercetalia ilicis), within which the Laurus nobilis microwoods gravitating in the Italo-Tyrrhenian biogeographical Province are framed, is also proposed

Activation of a bis-(phenoxyimine) titanium (IV) catalyst using different aluminoxane co-catalysts

The activation of a bis-phenoxyimine catalyst based on titanium (IV) using different aluminoxanes (MAO, PMAO and MMAO12) has been studied. The effect of a co-catalyst modifier (BHT) used in combination with the MAO has been also tested. In particular, the effect of the activation time between the catalyst and the different aluminoxanes has been taken into consideration. On increasing the activation time between catalyst and the different aluminoxanes and TMA-free MAO, differences in the catalyst activities have been observed. UHMWPEs having a reduced number of entanglements have been synthesized activating the FI catalyst with MAO and TMA-free MAO. The obtained reactor powders can be solid-state processed below the melting temperature in order to obtain high modulus/high tenacity tapes used for body armor and vehicle protection applications

The superfamily keeps growing: Identification in trypanosomatids of RibJ, the first riboflavin transporter family in protists

Background: Trypanosomatid parasites represent a major health issue affecting hundreds of million people worldwide, with clinical treatments that are partially effective and/or very toxic. They are responsible for serious human and plant diseases including Trypanosoma cruzi (Chagas disease), Trypanosoma brucei (Sleeping sickness), Leishmania spp. (Leishmaniasis), and Phytomonas spp. (phytoparasites). Both, animals and trypanosomatids lack the biosynthetic riboflavin (vitamin B2) pathway, the vital precursor of flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) cofactors. While metazoans obtain riboflavin from the diet through RFVT/SLC52 transporters, the riboflavin transport mechanisms in trypanosomatids still remain unknown. Methodology/Principal findings: Here, we show that riboflavin is imported with high affinity in Trypanosoma cruzi, Trypanosoma brucei, Leishmania (Leishmania) mexicana, Crithidia fasciculata and Phytomonas Jma using radiolabeled riboflavin transport assays. The vitamin is incorporated through a saturable carrier-mediated process. Effective competitive uptake occurs with riboflavin analogs roseoflavin, lumiflavin and lumichrome, and co-factor derivatives FMN and FAD. Moreover, important biological processes evaluated in T. cruzi (i.e. proliferation, metacyclogenesis and amastigote replication) are dependent on riboflavin availability. In addition, the riboflavin competitive analogs were found to interfere with parasite physiology on riboflavin-dependent processes. By means of bioinformatics analyses we identified a novel family of riboflavin transporters (RibJ) in trypanosomatids. Two RibJ members, TcRibJ and TbRibJ from T. cruzi and T. brucei respectively, were functionally characterized using homologous and/or heterologous expression systems. Conclusions/Significance: The RibJ family represents the first riboflavin transporters found in protists and the third eukaryotic family known to date. The essentiality of riboflavin for trypanosomatids, and the structural/biochemical differences that RFVT/SLC52 and RibJ present, make the riboflavin transporter -and its downstream metabolism- a potential trypanocidal drug target.Fil: Balcazar, Dario Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; ArgentinaFil: Vanrell, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Romano, Patricia Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Pereira, Claudio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Goldbaum, Fernando Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Bonomi, Hernán Ruy. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Carrillo, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; Argentin

Telemedicine for Diabetic Retinopathy Screening in Croatia: A Dream That Could Become a Reality

Diabetic retinopathy (DR) is the leading cause of preventable blindness in working-age adults associated with devastating personal and socioeconomic consequences. The increasing use of anti-vascular endothelial growth factor (anti-VEGF) agents over the past decade and telemedicine implementation in systematic DR screening resulted in a decliningtrend of new blindness due to diabetes in several countries. Telemedicine is the remote delivery of healthcare services over the telecommunications infrastructure. It allows healthcare providers to evaluate, diagnose, and treat patients without the need for an in-person visit. Teleophthalmology is a telemedicine branch, mostly focused on diabetic retinopathy and retinopathy of prematurity. Screening for DR in Croatia is commonly performed annually, only by ophthalmologists using dilated slit-lamp biomicroscopic fundus examination. Due to the insufficient number of ophthalmologists and the lack of a formal call system, many diabetic patients do not perform annual screening. In an ideal DR screening model in Croatia, each diabetes center in university or general hospitals throughout Croatia (17 centers) would have one small digital fundus camera and an educated nurse who would perform dilated fundus photography. Electronic images from diabetes centers would be transferred for remote grading to the same hospitals’ ophthalmology departments or a central grading center for DR screening in Croatia. Grading for DR would be performed by an ophthalmologist, medical retina specialist. Patients would be annually invited by mail from the National Diabetes Registry to come to the nearest diabetes center for a fundus photographing and DR screening. Each patient with a positive result would be promptly referred to the medical retina specialist at the closest ophthalmology department for further examination and treatment

Underactuated Robotic Fish Control: Maneuverability and Adaptability Through Proprioceptive Feedback

Bioinspired robotics is a promising technology for minimizing environmental disruption during underwater inspection, exploration, and monitoring. In this research, we propose a control strategy for an underactuated robotic fish that mimics the oscillatory movement of a real fish’s tail using only one DC motor. Our control strategy is bioinspired to Central Pattern Generators (CPGs) and integrates proprioceptive sensory feedback. Specifically, we introduced the angular position of the tail as an input control variable to integrate a feedback into CPG circuits. This makes the controller adaptive to changes in the tail structure, weight, or the environment in which the robotic fish swims, allowing it to change its swimming speed and steering performance. Our robotic fish can swim at a speed between 0.18 and 0.26 body lengths per second (BL/s), with a tail beating frequency between 1.7 and 2.3 Hz. It can also vary its steering angular speed in the range of 0.08 rad/s, with a relative change in the curvature radius of 0.25 m. With modifications to the modular design, we can further improve the speed and steering performance while maintaining the developed control strategy. This research highlights the potential of bioinspired robotics to address pressing environmental challenges while improving solutions efficiency, reliability and reducing development costs

Postpartum Ovarian Vein Thrombosis

Postpartum ovarian vein thrombosis carries a significant risk of morbidity and mortality if not recognized early and managed appropriately

Bubrežna funkcija je povezan s razvojem katarakte u bolesnika sa šećernom bolešću tipa 2

In this study, we investigated the impact of renal function, metabolic risk factors, and duration of diabetes on cataract development in patients with type 2 diabetes (T2DM). This study was cross-sectional and included 107 T2DM (67 male/40 female). Renal function was estimated with a creatinine-based formula (eGFR) and with albumin/creatinine (A/C) ratio. Patients were divided into three groups according to the LOCSIII classification: group 1 represents patients with clear crystalline lens (n=16), group 2 represent patients with initial cataract (n=74), and group 3 represents patients with immature cataract (n=17). Compared to group 1, group 3 had significantly longer diabetes duration (17.12±6.38 vs. 10.81±4.09 years; p=0.004) and marginally higher HbA1c (7.11±1.41 vs. 6.38±0.83%; p=0.057). Diastolic blood pressure (DBP) was also significantly higher (90.94±15.41 vs. 76.47±6.32 mmHg; p=0.002) while eGFR was significantly lower (53 ± 18 vs. 72 ± 12 ml/min- 11.73m-2; p=0.014). In logistic regression analysis, DBP (AOR=1.06, 95%CI 1.00-1.12, p=0.039) and eGFR (AOR=3.02, 95%CI 1.07-8.49, p=0.034) had a significant influence on cataract development even after adjustment for well-known risk factors HbA1c and duration of diabetes. The results of the study suggest a connection between renal function and cataract development in T2DM.Cilj istraživanja bio je istražiti utjecaj trajanja šećerne bolesti (ŠB), metaboličkih rizičnih čimbenika i bubrežne funkcije na razvoj katarakte u bolesnika sa šećernom bolešću tipa 2 (ŠB2). Ovo presječno istraživanje je uključilo 107 bolesnika sa ŠB2 (67 muškaraca/40 žena). Bubrežna funkcija je procijenjena određivanjem glomerularne filtracije (GF) i omjerom albumin/ kreatinin (A/K) u urinu. Bolesnici su prema LOCS III bili podijeljeni u tri skupine: sk. 1 - bolesnici s prozirnom očnom lećom (n=16), sk. 2 - bolesnici s početnom kataraktom (n=74) i sk. 3 - bolesnici s nezrelom kataraktom (n=17). Bolesnici u sk. 3 imali su značajno duže trajanje ŠB (17.12±6.38 vs. 10.81±4.09 godina; p=0.004) i granično viši HbA1c (7.11±1.41 vs. 6.38±0.83%; p=0.057) nego oni u sk. 1. Dijastolički krvni tlak (DKT) bio je značajno viši (90.94±15.41 vs. 76.47±6.32 mmHg; p=0.002), a procijenjena GF značajno niža (53±18 vs. 72±12 mlmin-11.73m-2; p=0.017) u sk. 3 nego u sk. 1. Logistička regresija je utvrdila da su DKT (AOR=1.06, 95%CI 1.00-1.12, p=0.039) i GF (AOR=3.02, 95%CI 1.07-8.49, p=0.034) povezani s razvojem katarakte u ŠB2 čak i nakon standardizacije rezultata za trajanje ŠB i HbA1c. Rezultati ovog istraživanja su pokazali da bubrežna funkcija ima važnu ulogu u razvoju katarakte u ŠB2