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Compositionally Driven Viscometric Behaviors of poly (Alkyl Methacrylates) in Lubricating Oils

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Advances in Chemical Engineering and Science 2022年第2期12卷 65-86页

作者： Reid A. patterson Christopher p. Kabb David M. Nickerson Eugene pashkovski Research and Development The Lubrizol Corporation Wickliffe USA

Viscosity index (VI) and shear stability index (SSI) are standard methods used in the lubricant industry to determine temperature-viscosity dependency and resistance to product degradation, respectively. A variety of oil-soluble polymers, including poly(alkyl methacrylates) (pAMAs) are routinely used to control these properties in fully-formulated liquid lubricants. In this report, we use reversible addition-fragmentation chain transfer (RAFT) polymerization to precisely target identical degrees of polymerization in a family of pAMAs with varying lauryl, hexyl, butyl, ethyl, and methyl groups. Then, expanding on previous methodology reported in the literature, we establish structure property relationships for these pAMAs, specifically looking at how intrinsic viscosity [η] and Martin interaction parameters KM relate to VI and SSI characteristics. While the intrinsic viscosity [η] is associated with the volume of macromolecules at infinite dilution, the parameter KM reflects the hydrodynamic interactions of polymer chains at actual polymer concentrations in lubricating oils. In this paper, we show that the dependence of VI on the non-dimensional concentration c/c* (or c[η]) can be presented in a form of master curve with shift factors proportional to KM that decreases with increasing size of alkyl groups. This finding implies that even in the dilute regime, the coil-expansion theory used to explain the effect of macromolecules on VI should be complemented with the idea of hydrodynamic interactions between polymer molecules that can be controlled by the choice of alkyl chains in the family of pAMAs.

关键词： Viscosity Index Shear Stability Index polymethacrylates Lubricating Oils

Superinfection of hepatitis E Virus as a cause of decompensation in liver cirrhosis due to hepatitis B virus

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Asian pacific Journal of Tropical Medicine 2009年第2期2卷 54-57页

作者： Manisha Jain Anita Chakravarti p Kar Mbbs Md Department of Microbiology Maulana Azad Medical College Department of Medicine Lok Nayak and Associated HospitalsNew Delhi-110019India

Objevtive:Super infection with hepatitis A virus(HAV ) and hepatitis E virus(HEV ) in the presence of underlying hepatocellular injury can cause severe *** endemic areas such as India,however most patients already have been exposed to HAV but could still be susceptible to HEV *** our study we determined the seroprevalence of anti-HAV IgM and anti-HEV IgM to assess the incidence of superinfection with these viruses in cirrhotic patients with the goal of defining the need for protection against these viruses and further correlate the presence of these viruses with the clinical ***:We studied 53 patients of cirrhosis as a result of Hepatitis B *** causes of decompensation were ruled out before their inclusion in the study *** sample from these patients was tested for HBsAg,anti HBc IgG,anti HEV IgM and anti HAV IgG and IgM by commercially available ELISA *** function test was done on all the patients and correlated with various serological ***:anti HBc IgG was present in all the cases of cirrhosis. Hepatitis B surface antigen was present in 20 out of 53 cases of *** of the patients demonstrated anti-HAV IgM,however one patient had anti-HEV ***:Superinfection with HAV in adult patient is uncommon in *** of acute HEV infection in decompensated cirrhosis is low in the present study but presence of HEV superinfection in one patient corroborates the apprehension of liver function deterioration following superinfection with HEV virus.

关键词： HEV HAV Superinfection Liver cirrhosis

An Easy Access to Oxime Ethers by pd-Catalyzed C—O Cross-Coupling of Activated Aryl Bromides with Ketoximes and Chalcone Oximes

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Chinese Journal of Chemistry 2020年第8期38卷 830-836页

作者： Reeta T.M.Rangarajan Raj pal Singh R.p.Singh Manjula Singh Centre for Fire Explosive and Environment SafetyDRDODelhiIndia Department of Chemistry University of DelhiDelhiIndia Department of Chemistry Sri Venkateswara CollegeUniversity of DelhiNew DelhiIndia Department of Chemistry Shivaji CollegeUniversity of DelhiNew DelhiIndia

An efficient pd-catalyzed method for C—O cross-coupling of ketoximes and chalcone oximes with activated aryl bromides and bromo-chalcones has been *** oxime ethers were obtained in good to excellent yields by[(π-allyl)pdCl]2/tBuXphos(L7)catalyst ***(L11)was also found to be effective for the oxime *** method offers an easy and smooth coupling of chalcone oximes with activated aryl bromides and bromo-chalcones,which has not been previously explored.

关键词： coupling coupling bromide

Three-hundred and sixty degrees of surgical approaches to the maxillary sinus

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2022年第1期8卷 42-53页

作者： Natalia C.Rezende Carlos D.pinheiro-Neto Luciano C.p.C.Leonel Jamie J.Van Gompel Maria peris-Celda Garret Choby Division of Rhinology and Skull Base Surgery Department of Otolaryngology-Head&Neck SurgeryMayo ClinicRochesterMinnesotaUSA Department of Neurologic Surgery Mayo ClinicRochesterMinnesotaUSA

Objectives:To demonstrate three-hundred and sixty degrees of maxillary sinus(MS)surgical approaches using cadaveric dissections,highlighting the step-by-step anatomy of each ***:Two latex-injected cadaveric specimens were utilized to perform surgical dissections to demonstrate different approaches to the *** procedures were documented with macroscopic images and endoscopic ***:Dissections were performed to approach the MS medially(endoscopic maxillary antrostomy and ethmoidectomy),anteriorly(Caldwell-Luc),superiorly(transconjunctival/transorbital approach),inferiorly(transpalatal approach),and posterolaterally(preauricular hemicoronal approach).Conclusion:A number of approaches have been described to address pathology in the *** should be familiar with indications,limitations,and surgical anatomy from different perspectives to approach the *** paper illustrates anatomic approaches to the MS with detailed step-by-step cadaveric dissections and case examples.

关键词： anatomy Caldwell-Luc dissection endoscopic sinus surgery infratemporal fossa maxillary sinus pterygopalatine fossa

Transient performance estimation of charge plasma based negative capacitance junctionless tunnel FET

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Journal of Semiconductors 2016年第2期37卷 66-70页

作者： sangeeta singh p.n.kondekar pawan pal Department of Electronics and Communication Engineering PDPM-Indian Institute of Information TechnologyDesign and Manufacturing(IIITDM)Jabalpur JabalpurMPIndia

We investigate the transient behavior of an n-type double gate negative capacitance junctionless tun- nel field effect transistor （NC-JLTFET）. The structure is realized by using the work-function engineering of metal electrodes over a heavily doped n＋ silicon channel and a ferroelectric gate stack to get negative capacitance be- havior. The positive feedback in the electric dipoles of ferroelectric materials results in applied gate bias boosting. Various device transient parameters viz. transconductance, output resistance, output conductance, intrinsic gain, intrinsic gate delay, transconductance generation factor and unity gain frequency are analyzed using ac analysis of the device. To study the impact of the work-function variation of control and source gate on device performance, sensitivity analysis of the device has been carried out by varying these parameters. Simulation study reveals that it preserves inherent advantages of charge-plasma junctionless structure and exhibits improved transient behavior as well.

关键词： negative capacitance intrinsic gain transconductance generation factor intrinsic bias boosting

Quality control of the parasitoid wasp Trichogramma brassicae (Hymenoptera: Trichogrammatidae) over 45 generations of rearing on Sitotroga cerealella

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Insect Science 2021年第1期28卷 180-190页

作者： Ehsan Ghaemmaghami Yaghoub Fathipour Abdoolnabi Bagheri Ali Asghar Talebi Gadi V.p.Reddy Department of Entomology Faculty of AgricultureTarbiat Modares UniversityTehranIran plant protection Research Department Hormozgan Agricultural and Natural Resources Research and Education CenterAgricultural Research Education and Extension Organization(AREEO)Bandar AbbasIran USDA-ARS-Southern Insect pest Management Research Unit StonevilleMississippiUSA

Trichogramma brassicae(Bezdenko)is an important biological control agent that has been used widely against many lepidopteran ***,colonies of Trichogramma are mass reared on factitious hosts such as Sitotroga cerealella(Olivier)over many *** this study,we evaluated the quality and performance of a colony of *** that had been reared for over 45 generations(G)using two-sex life table parameters and parasitism *** found that female adult longevity was significantly different among sequential generations,ranging from 5.58±2.5 d(at G5)to 3.75±1.42 d(at G45).However,no significant difference was found in male adult longevity among different *** female wasps survived longer until the 15th gener・ation,they allocated more days for egg laying at G5 and *** highest values of gross reproductive rate(GRR),net reproductive rate(7.),intrinsic rate of increase(r),finite rate of increase(λ)and mean generation time(T)were found in G5 and GIO,which also showed significantly higher *** significant difference in the finite parasitism rate(co)was found among generations up to *** results suggest that *** wasps held under continuous laboratory rearing can be used successfully in biological control programs until the 15th generation without any loss of quality or ***,laboratory mass rearing colonies declined in quality after 15 generations and we suggest that they should be rejuvenated regularly by adding field-collected parasitoids periodically.

关键词： biological control generation-dependent demography mass rearing parasitism rate Trichogramma brassicae

Celeboxib-mediated neuroprotection in focal cerebral ischemia: an interplay between unfolded protein response and inflammation

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Neural Regeneration Research 2022年第2期17卷 302-303页

作者： Maria Santos-Galdiano Diego perez-Rodriguez Arsenio Fernandez-Lopez Area de Biologia Celular Instituto de BiomedicinaCampus de Vegazana s/nUniversidad de LeonLeonSpain Neural Therapies SL Campus de Vegazana s/nLeónSpain Department of Clinical and Movement Neurosciences UCL Queen Square Institute of NeurologyLondonUK

Ischemic stroke results from the temporary or permanent lack of blood supply in the brain due to the occlusion of a brain blood vessel. Around 85% of patients with cerebrovascular accidents suffer from ischemic strokes.

关键词： inflammation cerebral ischemia

Determining the need for a thoracoscopic approach to treat a giant hiatal hernia when abdominal access is poor

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World Journal of Gastrointestinal Surgery 2023年第12期15卷 2739-2746页

作者： Francisco Javier pérez Lara Rogelio Zubizarreta Jimenez Tatiana prieto-puga Arjona pilar Gutierrez Delgado Juan Manuel Hernández Carmona Jose Manuel Hernández Gonzalez Maria pitarch Martinez Department of Surgery Hopital de AntequeraAntequera 29200Spain DOXA MicrofluidicsRincon de la Victoria 29730Spain Department of Surgery HRU Carlos HayaUnidad Cirugia Hepatobiliopancreat&TrasplantesMalaga 29200Spain

BACKGROUND Giant hernias present a significant challenge for digestive *** approach taken(laparoscopic vs thoracoscopic)depends largely on the preferences and skills of each surgeon,although in most cases today the laparoscopic approach is *** To determine whether patients presenting inadequate laparoscopic access to the intrathoracic hernial sac obtain poorer postoperative results than those with no such problem,in order to assess the need for a thoracoscopic *** For the retrospective series of patients treated in our hospital for hiatal hernia(n=112),we calculated the laparoscopic field of view and the working area accessible to surgical instruments,by means of preoperative imaging tests,to assess the likely outcome for cases inaccessible to *** patients with giant hiatal hernias for whom a preoperative calculation suggested that the laparoscopic route would not access all areas of the intrathoracic sac presented higher rates of perioperative complications and recurrence during follow-up than those for whom laparoscopy was *** difference was statistically ***,the insertion of mesh did not improve results for the non-accessible *** For patients with giant hiatal hernias,it is essential to conduct a preoperative evaluation of the angle of vision and the working area for *** parts of the intrathoracic sac are inaccessible laparoscopically,the thoracoscopic approach should be considered.

关键词： Hiatal hernia Abdominal surgery Laparoscopy Thoracoscopy surgery

Comparison between linseed expeller and canola expeller on concentrate intake,and circulating inflammatory mediators in Holstein calves

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Animal Nutrition 2020年第1期6卷 47-53页

作者： pedro Melendez Romina Ramirez Maria p.Marin Mario Duchens pablo pinedo College of Veterinary Medicine University of GeorgiaTiftonGA31793USA College of Veterinary Medicine University Santo TomasVina del MarChile College of Veterinary Medicine University of ChileSantiagoChile Department of Animal Sciences Colorado State UniversityFort CollinsCO80523USA College of Veterinary Medicine University of MissouriColumbiaMO 61203USA

The objective of this study was to compare the effect of linseed and canola expeller on average daily weight gain(ADG),concentrate intakes,incidence of diarrhea,serum haptoglobin,interleukin(IL)-1,and resolvin-E1 in female Holstein calves from birth to weaning.A sample size of 20 calves per group was calculated and were randomly allocated at the time of *** group(LIN)was fed a starter with linseed expeller,while canola group(CAN)received a similar concentrate,but with canola *** expellers were included at a rate of 25%dry matter(DM)basis of the *** waste milk was fed twice a day until *** were weighed at birth,30,and 60 d of *** intake was evaluated daily from 5 to 60 d.A blood sample was obtained at birth,14,28,35,and 49 d of age,and bovine serum resolvin-El,haptoglobin,and IL-1 were assayed by commercial enzyme-linked immunosorbent assay(ELISA)*** of diarrhea and the duration of the events were also *** effect of the interaction group by time on body weight(BW)and starter intake was not significant(p>0.05).Average daily gains(ADG)from 0 to 60 d for CAN and LIN groups were 0.680 and 0.675 kg/d(p>0.05),*** of diarrhea were 25%and 45%for CAN and LIN groups,respectively(p=0.18).LIN group had greater concentrations of IL-1 at d 21,haptoglobin at d 7,and resolving-El at d 14 and 49 than CAN group,*** is concluded that BW at weaning,ADG,and concentrate intakes were not different between groups fed starters containing linseed or canola expeller(25%inclusion).The concentrations of cytokines and haptoglobin were the greatest in LIN group.

关键词： Linseed expeller Omega-3 fatty acids Calf Daily gain Diarrhea