Layered D2D NOMA

This paper investigates a layered power allocation(PA)non-orthogonal multiple access(NOMA)scheme for device-to-device(D2D)relaying networks,where the strategy of partial data transmission at relay nodes are adopted to improve the efficiency of resources.In addition,to satisfy different quality-of-service(QoS)requirements from multiple users,layered and grouped manners are involved.Moreover,the closed-form expressions in terms of the sum-rate(SR)and outage probability of the proposed scheme are derived for independent Rayleigh fading channels,which demonstrates our theoretical analysis.Both analytical and simulation results are provided to show the superiority of our proposed scheme compared with existing works.

Lymphoepithelioma-like carcinoma of the upper urinary tract: A systematic review of case reports

BACKGROUND Lymphoepithelioma-like carcinomas(LELCs)are rare,malignant epithelial tumors,generally considered a subtype of squamous cell carcinoma.LELCs are undifferentiated and can occur in multiple tissues,although LELCs in the urinary tract are extremely rare.As such,evidence does not provide clinicians with guidelines for the best practices.Even though this is a rare disease,it is associated with high morbidity and mortality.Therefore,we must learn to differentiate LELC types and identify risk factors for early identification.AIM To develop an evidence base to guide clinicians treating primary LELCs of the upper urinary tract(UUT-LELC).METHODS We performed a systematic review of all reports on UUT-LELC from the first published case in 1998 until October 2019,according to the PRISMA.A database was then developed by extracting data from previously published reports in order to analyze interactions between clinical characteristics,pathological features,interventions and outcomes.Survival was analyzed using Kaplan–Meier estimates,which were compared using log rank tests.RESULTS A total of 28 previously published cases were identified for inclusion.The median age was 72 years with a male to female ratio of 4:3.Pure type LELCs were most common with 48.3%(n=14),followed by 37.9%(n=11)predominant LELCs and 3.4%(n=1)focal LELCs.Epstein-Barr virus testing was negative in all cases.Fourteen patients received radical nephroureterectomy(RNU)-based intervention.Twenty-three patients survived with no evidence of further metastasis,although six died before the median 18 mo follow-up point.Survival analysis suggests pure histological subtypes,and patients who receive complete tumor resection have more favorable prognoses.As always in cancer care,early identification generally increases the probability of interventional success.CONCLUSION The most effective treatment for UUT-LELC is RNU-based therapy.Since cases are few in number,case reporting must be enhanced and publishing encouraged to both save and prolong lives.

Folic Acid Modified Polymeric Micelles for Intravesical Instilled Chemotherapy

In this study, a targeting micellar drug delivery system was developed for intravesical instilled chemotherapy of bladder cancer. The amphiphilic diblock copolymer poly（？-caprolactone）-block-poly（ethylene glycol）（PCL-b-PEO） with functional amino group（NH2） at the end of PEO block was synthesized. Then the copolymer was conjugated with folic acid（FA） and fluorescein isothiocyannate（FITC） via the PEO-NH2 terminus, and then assembled into micelles with the target moiety and fluorescence labeling. In addition, drug loaded micelles were also fabricated with anticancer drug doxorubicin（DOX） encapsulated in the hydrophobic core. The micelles were characterized in terms of size, drug loaded efficiency and critical micellization concentration（CMC） by means of DLS, UV and fluorescence spectra. In vitro cellular uptake and cytotoxicity studies showed that FA modified PCL-b-PEO-FA micelles have a greater targeting efficiency to human bladder cancer cell（T-24 cell） compared to PCL-b-PEO-NH2 micelles due to the conjugation of FA on the surface, while no targeting effect to normal tissue originated human embryonic kidney 293（HEK-293） cells was observed, enabling the micelles a promising drug carrier for intravesical instilled chemotherapy of bladder cancer.

Catalytic fast pyrolysis of walnut shell for alkylphenols production with nitrogen-doped activated carbon catalyst

Alkylphenols are a group of valuable phenolic compounds that can be derived from lignocellulosic biomass.In this study,three activated carbons(ACs)were prepared for catalytic fast pyrolysis(CFP)of walnut shell to produce alkylphenols,including nitrogen-doped walnut shell-derived activated carbon(N/WSAC),nitrogen-doped rice husk-derived activated carbon(N/RHAC)and walnut shell-derived activated carbon(WSAC).Pyrolysis-gas chromatography/mass spectrometry(Py-GC/MS)experiments were carried out to reveal the influences of AC type,pyrolytic temperature,and AC-to-walnut shell(AC-to-WS)ratio on the product distributions.Results showed that with nitrogen doping,the N/WSAC possessed stronger capability than WSAC toward the alkylphenols production,and moreover,the N/WSAC also exhibited better effects than N/RHAC to prepare alkylphenols.Under the catalysis of N/WSAC,yields of alkylphenols were significantly increased,especially phenol,cresol and 4-ethylphenol.As the increase of pyrolytic temperature,the alkylphenols yield first increased and then decreased,while high selectivity could be obtained at low pyrolytic temperatures.Such a trend was also observed as the AC-to-WS ratio continuously increased.The alkylphenols production achieved a maximal yield of 44.19 mg/g with the corresponding selectivity of 34.7%at the pyrolytic temperature of 400℃and AC-to-WS ratio of 3,compared with those of only 4.67 mg/g and 6.1%without catalyst.In addition,the possible formation mechanism of alkylphenols was also proposed with the catalysis of N/WSAC.

Toward better understanding vacuum ultraviolet-iodide induced photolysis via hydrogen peroxide formation,iodine species change,and difluoroacetic acid degradation

Recently,a photochemical process induced by ultraviolet(UV),vacuum UV(VUV),and iodide(I–)has gained attention for its robust potential for contaminant degradation.However,the mechanisms behind this process remain unclear because both oxidizing and reducing reactants are likely generated.To better understand this process,this study examined the evolutions of hydrogen peroxide(H_(2)O_(2))and iodine species(i.e.,iodide,iodate,and triiodide)during the UV/VUV/I–process under varying pH and dissolved oxygen(DO)conditions.Results show that increasing DO in water enhanced H2O2 and iodate production,suggesting that high DO favors the formation of oxidizing species.In contrast,increasing pH(from 6.0 to 11.0)resulted in lower H_(2)O_(2) and iodate formation,indicating that there was a decrease of oxidative capacity for the UV/VUV/I–process.In addition,difluoroacetic acid(DFAA)was used as an exemplar contaminant to verify above observations.Although its degradation kinetics did not follow a constant trend as pH increases,the relative importance of mineralization appeared declining,suggesting that there was a redox transition from an oxidizing environment to a reducing environment as pH rises.The treatability of the UV/VUV/I–process was stronger than UV/VUV under pH of 11.0,while UV/VUV process presented a better performance at pH lower than 11.0.

EFFECT OF SURFACE CHARGE OF POLYMERIC MICELLES ON IN VITRO CELLULAR UPTAKE

This work focuses on the interaction between polymeric micelles with different charged surfaces and cancer cells in order to study the influence of surface charge on the in vitro cellular uptake efficiency. The amphiphilic diblock copolymers poly（e-caprolaetone）-b-poly（ethylene oxide） （PCL-b-PEO） with different functional groups at the end of hydrophilic block were synthesized. The functional groups endue the micelles with different charges on the surfaces. The cellular uptake of micelles to T-24 cells （human bladder tumor cells）, HepG2 cells （human liver hepatocellular carcinoma cell line） and Hela cells （human epithelial cervical cancer cells） was studied by means of flow cytometer and confbcal laser scanning microscopy. The results indicate that the surface charges showed great influence on zeta potential of micelles at different pH values. The in vitro cellular uptake efficiency of micelles with different charged surfaces demonstrated different cellular uptake patterns to three kinds of cancer cells.

Mechanistic insights for efficient inactivation of antibiotic resistance genes: a synergistic interfacial adsorption and photocatalytic-oxidation process

Advanced oxidation processes(AOPs) have been applied to address multiple environmental concerns including antibiotic resistance genes(ARGs). ARGs have shown an increasing threat to human health,and they are either harbored by antibiotic-resistant bacteria(ARB) or free in the environment.However, the control of ARGs has been substantially limited by their low concentration and the limited knowledge about their interfacial behavior. Herein, a novel AOP catalyst, Ag/TiO_(2)/graphene oxide(GO),combined with a polyvinylidene fluoride(PVDF) ultrafiltration membrane was designed with a synergistic interfacial adsorption and oxidation function to inactivate ARGs with high efficiency in both model solutions and in secondary wastewater effluent, especially when the residue concentration was low.Further analysis showed that the mineralization of bases and phosphodiesters mainly caused the inactivation of ARGs. Moreover, the interfacial adsorption and oxidation processes of ARGs were studied at the molecular level. The results showed that GO was rich in sp^(2) backbones and functional oxygen groups,which efficiently captured and enriched the ARGs via p-p interactions and hydrogen bonds. Therefore,the photogenerated active oxygen species attack the ARGs by partially overcoming the kinetic problems in this process. The Ag/Ti O2/GO catalyst was further combined with a PVDF membrane to test its potential in wastewater treatment applications. This work offers an efficient method and a corresponding material for the inactivation and mineralization of intra/extracellular ARGs. Moreover, the molecularlevel understanding of ARG behaviors on a solid–liquid interface will inspire further control strategies of ARGs in the future.

High temperature thermo-photocatalysis driven carbon removal in direct biogas fueled solid oxide fuel cells

Solid oxide fuel cells(SOFCs)can directly convert renewable biogas into electricity with high efficiency at high temperature,however the long-term stability of SOFCs is significantly affected by the carbon deposition on the anode during cell operation.Herein,we report a novel carbon removal approach by high temperature infrared light driven photocatalytic oxidation.Upon the comparison of electrochemical performance of Ni-YSZ anode and TiO_(2)modified Ni-YSZ anode in the state-of-the-art single cell(Ni-YSZ/YSZ/LSCM),the modified anodes exhibit markedly improved peak powder density with simulated biogas fuel(70%CH_(4)+30%CO_(2))at 850℃with less coking after 40 h operation.The high activity and carbon deposition resistance of the modified anode is possibly attributed to the in situ generated hydroxyl radical from the reduced TiO_(x)powder under high temperature infrared light excitation,which is supported by detailed analysis of microstructural information of anodes and the powder-based thermo-photocatalytic experiments.

Atom Recombination of Difluorocarbene Enables 3-Fluorinated Oxindoles from 2-Aminoarylketones

Contrary to the traditional implementation as a difluoromethyl group and recently disclosed role of C1 synthons in synthetic organic chemistry,difluorocarbene(:CF_(2))is reported herein to proceed in unprecedented atom recombination as both a C1 synthon and F1 reagent simultaneously to render valuable 3-fluorinated oxindoles from 2-aminoarylketones.The reaction does not require catalyst and features a broad range of substrates with good functional group compatibility and ease of execution.This transformation could be employed to the quick-constructions of certain bioactive molecule derivatives.The mechanistic experiments and density functional theory(DFT)calculations indicate that this atom recombination reaction of:CF_(2) for the synthesis of 3-fluorinated oxindoles may involve a rearrangement process of epoxide intermediates.