Trap Experiments Research Articles

Improving the photocatalytic activity of NH2-UiO-66 by facile modification with Fe(acac)3 complex for photocatalytic water remediation under visible light illumination

A new and cost-effective photocatalyst was prepared via a facile modification of NH2-UiO-66 with an iron (III) complex i.e. Fe(acac)3, in order to enhance the optical properties and charge separation efficiency of pristine MOF. According to the results of UV-Vis DRS and Tauc plot calculations, the band gap value decreased from 2.7 eV to 2.46 eV for final Fe-UiO-66 photocatalyst, showing the improvement of light absorption in the visible region. Moreover, the photoluminescence (PL) and electrochemical impedance spectroscopies (EIS) confirmed the efficient separation of electron-hole carriers after introduction of Fe(acac)3 into the MOF structure. The photo-Fenton reaction was carried out in the presence of photocatalyst and hydrogen peroxide under white LED illumination for degradation of organic dyes (methyl violet 2B, rhodamine B, malachite green, and methylene blue) and tetracycline (TC) as the examples of water pollutants. A significant dye and TC removal up to 92% and 85% were obtained in photo-Fenton system containing Fe-UiO-66 photocatalyst, respectively. The trap experiment using isopropyl alcohol (IPA) and Na2EDTA demonstrated that the major active species for pollutants degradation are hydroxyl radicals (•OH) and photo-generated holes (h+), respectively. Besides, the transfer of photo-generated electron (e-) to Fe(acac)3 complex resulted in the reduction of Fe3+ to Fe2+ and acceleration of the photo-Fenton reaction. Also, the photocatalyst was found to be very stable during the photo-Fenton reaction according to physicochemical analyses, and it can be reused four times without remarkable decrease in activity.

Base-Mediated Radical Borylation of Alkyl Sulfones.

A practical and direct method was developed for the production of versatile alkyl boronate esters via transition metal‐free borylation of primary and secondary alkyl sulfones. The key to the success of the strategy is the use of bis(neopentyl glycolato) diboron (B2neop2), with a stoichiometric amount of base as a promoter. The practicality and industrial potential of this protocol are highlighted by its wide functional group tolerance, the late‐stage modification of complex compounds, no need for further transesterification, and operational simplicity. Radical clock, radical trap experiments, and EPR studies were conducted which show that the borylation process involves radical intermediates.

Inertial and gravitational effects on a geonium atom

We reveal all linear order inertial and gravitational effects on a non-relativistic Dirac particle (mass m) on the Earth up to the order of 1/m in the Foldy–Wouthuysen-like expansion. Applying the result to Penning trap experiments where a Dirac particle experiences the cyclotron motion and the spin precession in a cavity, i.e. a geonium atom, we study modifications to the g-factor of such as the electron. It is shown that each correction from gravity has different dependence on the cyclotron frequency and the mass m. Therefore, their magnitude change depending on situations. In a particular case of an electron g-factor measurement, the dominant correction to the observed g-factor comes from effects of the Earth’s rotation, which is δg/2 ≃ 5.2 × 10−17. It may be detectable in the near future.

SlyD Accelerates trans-to-cis Prolyl Isomerization in a Mechanosignaling Protein under Load.

Prolyl isomerization is recognized as one of the key regulatory mechanisms, which plays a crucial role in cell signaling, ion channel gating, phage virus infection, and molecular timing. This isomerization is usually slow but often accelerated by an enzyme, called peptidyl-prolyl isomerase (PPIase). In the current project, we investigate using single-molecule force spectroscopy (SMFS) the impact of a bacterial PPIase, SlyD, on the cis-trans isomerization of the proline 2225 (P2225) in an isolated 20th domain of a cytoskeletal mechanosensing protein filamin-A (FlnA20). To explore the FlnA20-PPIase interaction, we have used multiple SMFS modes, like constant velocity, constant distance, and jumping trap experiments. In our previous study, we reported the unique nature of the P2225, which is conserved in all naturally occurring filamins and can slowly (minutes) interconvert between cis-trans isomers, in absence of any PPIase. Our current results show a staggering 25-fold acceleration of the trans-to-cis isomerization rate in the presence of saturating SlyD concentration (7.25 μM) compared to the unenzymatic condition. A SlyD concentration-dependent depletion of the trans isomeric lifetime was also observed. Additionally, we observed that SlyD stabilizes the cis-isomer in the native state of FlnA20 by ∼2 kBT. This is the first single-molecule observation of the cis-trans isomerization catalysis by a PPIase in a mechanosensing protein.

Circular Rna CircLAMA3 Inhibit Proliferation of Bladder Cancer by Directly Binding mRNA

Background: Increasing evidence confirmed that circRNAs play a variety of roles in the biological processes of cancer, including tumor cell proliferation, differentiation, and apoptosis. In this study, we identified differentially expressed circRNAs and explored its regulatory role in the development of bladder cancer. Methods: circRNA microarray and qRT-PCR were used to identify the dysregulation of circLAMA3 in bladder cancer. The precise role of circLAMA3 in cell proliferation was identified by bioinformatics analysis, RNA-fluorescence in situ hybridization, and function loss and gain experiment. The potential mechanism of circLAMA3 in bladder cancer by assessed via Western blotting, luciferase reporter gene, and TRAP experiment. Findings: Functional experiments demonstrated that circLAMA3 significantly inhibited the proliferation, migration, and invasion of bladder cancer cell and also inhibited bladder cancer growth in vivo. Mechanically, CircLAMA3 directly binds MYCN mRNA and promotes the degradation of MYCN mRNA to reduce MYCN protein expression in bladder cancer cells. Decreased MYCN protein inhibits the promoter activity and expression level of CDK6. Ultimately, circLAMA3 affects DNA replication by downregulating CDK6, resulting in G0/G1 phase arrest and inhibition of bladder cancer proliferation. Interpretation: We report a new regulatory mechanism that circRNA might directly bind mRNA and participate in the regulation of this mRNA fate. Moreover, CircLAMA3 can significantly affect the progress of bladder cancer and is expected to be potential biomarkers and therapeutic targets for bladder cancer diagnosis and treatment. Funding: This work was supported by the National Natural Science Foundation of China(NSFC81903356). Declaration of Interest: None to declare. Ethical Approval: All of the organizational uses were approved by Ethics Committee of Wenzhou Medical University and the patients provided informed consent.

Abstract 931: From bench to bedside: Using ProTide chemistry to transform 3'-deoxyadenosine into the novel anti-cancer agent Nuc-7738

Abstract Background: 3'-deoxyadenosine (3'-dA; also known as cordycepin) is a nucleoside analog that has shown potent anti-cancer activity in non-clinical studies but has not been clinically developed because of its vulnerability to rapid degradation by the circulating enzyme adenosine deaminase (ADA) and its poor uptake into cancer cells. The ProTide NUC-7738 is a pre-activated and protected nucleotide analog (3'-dA 5'monophosphate; 3'-dAMP) specifically designed to overcome the limitations of 3'-dA. NUC-7738's phosphoramidate moiety renders it resistant to ADA degradation. Here we compared NUC-7738 to 3'-dA in several model systems prior to conducting a first-in-class dose-escalation/expansion study of NUC-7738 in patients with advanced cancers. Materials and Methods: To determine the potency of NUC-7738, IC50 values were measured in multiple cancer cell lines and compared to the parent compound, 3'-dA. Chemical inhibitors of ADA and other 3'-dA processing enzymes were applied to assess the relative ability of NUC-7738 to bypass these pathways. Using genome-wide gene-trap screens and RNA sequencing we compared mechanisms of action (MOA) for NUC-7738 and 3'-dA. Results: NUC-7738 demonstrated up to 185x greater anti-cancer potency than 3'-dA across a variety of cancer cells lines. Gene trap experiments showed that the intracellular activating enzyme adenosine kinase (ADK) and the hENT1 transporter were amongst the highest enriched genes for 3'-dA, whilst no enrichments for these genes were observed in NUC-7738 treated cells. In support of this, in vitro inhibition assays showed that unlike 3'-dA, NUC-7738 is resistant to ADA breakdown, is not reliant on hENT1 transport for its cellular uptake, and is independent of ADK for its activity. As expected, RNA sequencing analysis demonstrated overlap between the MOA of NUC-7738 and 3'-dA; both cause cancer cell death via the intrinsic apoptosis pathway and suppression of pro-survival signaling. Further investigation of gene candidates was employed in ex-vivo cancer kidney cancer samples. Conclusion: Phosphoramidate chemistry was used to transform the nucleoside analog 3'-dA into NUC-7738, rendering it resistant to degradation by ADA and enabling it to enter cancer cells independent of nucleoside transporters, both of which contribute to NUC-7738's substantially greater in vitro potency compared to 3'-dA. The gene trap approach allowed a sophisticated comparison of the MOA of NUC-7738 with 3'-dA. By overcoming the resistance mechanisms associated with 3'-dA, NUC-7738 generates higher levels of the active anti-cancer metabolite in cancer cells. These data supported the initiation of NuTide:701, a first-in-human Phase I study assessing the safety, tolerability, pharmacokinetics and pharmacodynamics of NUC-7738 in patients with advanced solid tumors that are resistant to conventional treatment. Citation Format: Hagen Schwenzer, Michaela Serpi, Valentina Ferrari, James Chettle, Josephine Morris, Ruud van Stiphout, Erica de Zan, Sebastian Nijman, Mustafa Elshani, Mary Kudsy, David Harrison, Gareth Bond, Sarah P. Blagden. From bench to bedside: Using ProTide chemistry to transform 3'-deoxyadenosine into the novel anti-cancer agent Nuc-7738 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 931.

An odorant-binding protein of Asian citrus psyllid, Diaphorina citri, participates in the response of host plant volatiles.

Odorant-binding proteins (OBPs) in insects contribute to the sensitivity of the olfactory system and connect external odorants to olfactory receptor neurons. Determination of the chemosensory functions in Diaphorina citri, a vector of the citrus Huanglongbing pathogen, may help in developing a potential target for pest management. Diaphorina citri showed dose-dependent electroantennogram recording (EAG) responses to 12 host plant volatiles. A two-choice behavioral trap experiment showed that four compounds (methyl salicylate, linalool, citral and R-(+)-limonene) that elicited high EAG responses also had significant attraction to adults. The expression profiles induced by these compounds were detected in nine OBP genes, DcitOBP1-9. DcitOBP3, DcitOBP6 and DcitOBP7 commonly showed significant upregulation or downregulation compared with the control. Microscale thermophoresis (MST) showed that the recombinant protein DcitOBP7 had high in vitro binding affinities (Kd < 10μm) to methyl salicylate, linalool and R-(+)-limonene, and moderate binding affinity to citral with a Kd value of 15.95 μm. Furthermore, RNA interference (RNAi)-suppressed messenger RNA (mRNA) expression of DcitOBP7 resulted in a significant reduction in EAG activity and in adult D. citri behavioral responses to tested volatiles and the preferred host, Murraya paniculata. The hydrophilic residue Arg107 of DcitOBP7 may have a key role in binding odorants via formation of hydrogen bonds. These results show that DcitOBP7 plays an important role in the olfactory response. This finding may provide new insight into the functions of OBP families in D. citri and aid in the development of safe strategies for managing D. citri populations. © 2021 Society of Chemical Industry.

A novel flower-like dual Z-scheme BiSI/Bi2WO6/g-C3N4 photocatalyst has excellent photocatalytic activity for the degradation of organic pollutants under visible light

Preparation of Z-scheme composite photocatalyst to degrade organic matter in water is the most popular research trend. However, due to the strict requirements of band edge energy level arrangement and interface contact, it is a great challenge to explore suitable photocatalytic materials to form Z-scheme photocatalytic system. In our work, a novel visible light driven double Z-scheme photocatalyst BiSI/Bi2WO6/g-C3N4 was successfully prepared by hydrothermal synthesis. The physicochemical properties of the materials were characterized by XRD, XPS, SEM, BET, UV–vis, PL, EIS and LC-MS. The photocatalytic degradation of tetracycline (TC), chlortetracycline (CTC) and rhodamine B (RhB) showed that BiSI/Bi2WO6/(20%) g-C3N4 had the best photocatalytic activity. The results free radical trap experiments demonstrate that h+ and O2− are the main free radicals in the photocatalytic process. Because of the heterojunction formed between BiSI, Bi2WO6 and g-C3N4, the electron conduction was accelerated, the photogenerated electrons and holes were separated effectively, and the photocatalytic performance of the composite was improved. Additionally, cycle test showed that BiSI/Bi2WO6/g-C3N4 hybrid material had stable degradation ability in the process of photodegradation. This unique heterojunction photocatalysis material has broad application prospects in the removal of organic pollutants and environmental treatment.

A 2-decade (1988–2009) record of diatom fluxes in the Mauritanian coastal upwelling: impact of low-frequency forcing and a two-step shift in the species composition

Abstract. Eastern boundary upwelling ecosystems (EBUEs) are among the most productive marine regions in the world's oceans. Understanding the degree of interannual to decadal variability in the Mauritania upwelling system is crucial for the prediction of future changes of primary productivity and carbon sequestration in the Canary Current EBUE as well as in similar environments. A multiyear sediment trap experiment was conducted at the mooring site CBmeso (“Cape Blanc mesotrophic”, ca. 20∘ N, ca. 20∘40′ W) in the highly productive coastal waters off Mauritania. Here, we present results on fluxes of diatoms and the species-specific composition of the assemblage for the time interval between March 1988 and June 2009. The temporal dynamics of diatom populations allows the proposal of three main intervals: (i) early 1988–late 1996, (ii) 1997–1999, and (iii) early 2002–mid 2009. The Atlantic Multidecadal Oscillation (AMO) appears to be an important driver of the long-term dynamics of diatom population. The long-term AMO-driven trend is interrupted by the occurrence of the strong 1997 El Niño–Southern Oscillation (ENSO). The extraordinary shift in the relative abundance of benthic diatoms in May 2002 suggests the strengthening of offshore advective transport within the uppermost layer of filament waters and in the subsurface and in deeper and bottom-near layers. It is hypothesized that the dominance of benthic diatoms was the response of the diatom community to the intensification of the slope and shelf poleward undercurrents. This dominance followed the intensification of the warm phase of AMO and the associated changes of the Atlantic Meridional Overturning Circulation. Transported valves (siliceous remains) from shallow Mauritanian coastal waters into the bathypelagic should be considered for the calculation and model experiments of bathy- and pelagic nutrients budgets (especially Si), the burial of diatoms, and the paleoenvironmental signal preserved in downcore sediments. Additionally, our 1988–2009 data set contributes to the characterization of the impact of low-frequency climate forcings in the northeastern Atlantic and will be especially helpful for establishing the scientific basis for forecasting and modeling future states of the Canary Current EBUE and its decadal changes.

How far can EPTs fly? A comparison of empirical flying distances of riverine invertebrates and existing dispersal metrics

The species composition of a community is driven by the dispersal capacity of the species forming that community and their ecological niche. While the ecological niches of EPTs (Ephemeroptera, Plecoptera and Trichoptera) are well-studied due to their wide use as indicators for the ecological status of freshwater ecosystems, their dispersal capacity has not yet been accurately characterized. Dispersion of the merolimnic EPT species during the terrestrial aerial adult stage is of special importance because the distance dispersed by active flight or passive wind drift is usually much larger compared to dispersion during the aquatic larval stage by active crawling or by drifting downstream.The aerial dispersal distance has been directly measured for only a small number of EPT species. For most other species, the dispersal capacity is assessed indirectly using species’ traits that are mainly based on expert judgement and dispersal indices derived from trait information. In this study, we compiled a database of European EPTs’ aerial dispersal distances reported in empirical studies and compared them to the dispersal capacity of the species as described by five different dispersal indices (original and modified versions of Li’s Dispersal Capacity Metric DCM and Sarremejane’s Species Flying Propensity SFP as well as relative wing length).The database included empirical data on 180 species, comprising 9.3% of European EPT species. Most data came from trap experiments with traps located at different distances from the assumed emergence point. Since the distance classes differed between studies and had to be translated to a fixed set of four distance classes here, several species had to be assigned to more than one class. To account for this uncertainty, five ordered logistic regression models, each one with a dispersal index as predictor and the ordinal-scaled aerial dispersal distance as response, were bootstrapped 10,000 times. In each run, species belonging to several distance classes were randomly assigned to a single class out of all possible classes. Since wing length had no significant effect on aerial dispersal distance in any of the 10,000 bootstrap runs, we question the use of this anatomical trait as an indicator for the aerial dispersal capacity. In contrast, a modified version of the DCM index was consistently related to the aerial dispersal distances (96%). The original SFP index had a significant effect in 100% of the model runs, indicating that this index is very well-suited as an indicator for the aerial dispersal capacity of European EPT species.This study facilitates the assessment of European EPT flying distances by providing a compilation of empirical data on the topic and by recommending an accurate indirect method when empirical data is not available.

Photocatalytic Oxidative Coupling of Arylamines for the Synthesis of Azoaromatics and the Role of O2 in the Mechanism.

The photocatalytic oxidative coupling of aryl amines to selectively synthesize azoaromatic compounds has been realized. Multiple different photocatalysts can be used to perform the general reaction; however, Ir(dF-CF3-ppy)2(dtbpy)+, where dF-CF3-ppy is 2-(2,4-difluorophenyl)-5-(trifluoromethyl)pyridine and dtpby is 4,4'-tert-butyl-2,2'-bipyridine, showed the greatest range of reactivity with various amine substrates. Both electron-rich and -deficient amines can be coupled with yields up to 95% under an ambient air atmosphere. Oxygen was deemed to be essential for the reaction and is utilized in the regeneration of the photocatalyst. Fluorescence quenching and radical trap experiments indicate an amine radical coupling mechanism that proceeds through a hydrazoaromatic intermediate before further oxidation occurs to form the desired azoaromatic products.

A New Measurement Method for High Voltages Applied to an Ion Trap Generated by an RF Resonator.

A new method is proposed to measure unknown amplitudes of radio frequency (RF) voltages applied to ion traps, using a pre-calibrated voltage divider with RF shielding. In contrast to previous approaches that estimate the applied voltage by comparing the measured secular frequencies with a numerical simulation, we propose using a pre-calibrated voltage divider to determine the absolute amplitude of large RF voltages amplified by a helical resonator. The proposed method does not require measurement of secular frequencies and completely removes uncertainty caused by limitations of numerical simulations. To experimentally demonstrate our method, we first obtained a functional relation between measured secular frequencies and large amplitudes of RF voltages using the calibrated voltage divider. A comparison of measured relations and simulation results without any fitting parameters confirmed the validity of the proposed method. Our method can be applied to most ion trap experiments. In particular, it will be an essential tool for surface ion traps which are extremely vulnerable to unknown large RF voltages and for improving the accuracy of numerical simulations for ion trap experiments.

Iron Catalyzed Isomerization of α‐Alkyl Styrenes to Access Trisubstituted Alkenes

Main observation and conclusionStereoselective isomerization of α‐alkyl styrenes is accomplished using a new iron catalyst supported by phosphine‐pyridine‐oxazoline (PPO) ligand. The protocol provides an atom‐efficient and operationally simple approach to trisubstituted alkenes in high yields with excellent regio‐ and stereoselectivities under mild conditions. The results of deuterium‐labelling and radical trap experiments are consistent with an iron‐hydride pathway involving reversible alkene insertion and β‐H elimination.

Coherent control of $$^{171}\mathrm{Yb}^{+}$$ ion qubit states and thermometry using motional decoherence

$$^{171} \mathrm{Yb}^{+}$$ ions were trapped in a quadrupole ion trap. A mode-locked pulse laser at 355 nm was used to generate a frequency comb to drive a Raman transition between the ground hyperfine qubit states of the Doppler cooled ion. Qubit transitions were driven in co-propagating and counter propagating laser beam geometries. In the co-propagating geometry, the coherence time and the fidelity of gate operations were obtained. By taking advantage of the phonon number sensitivity of the Rabi frequency in the counter-propagating geometry, we measured the center of mass temperature of the trapped ion near the Doppler limit which can be used for general thermometry in the ion trap experiment.

Online Adaptation to "Gotcha! Which fly trap is the best? An introduction to experimental data collection and analysis"

We present here a simple and engaging experiment capitalizing on the universal need to rid our homes of fruit flies to teach experimental design and analysis. In an earlier <a href="https://doi.org/10.24918/cs.2019.35">paper</a>, we described an experiment in which students learn the scientific process by attempting to answer the question, &quot;what is the best way to catch fruit flies?&quot; The experiment was designed to be easily adaptable to the resources available to the instructor. With the recent increase in schools opting for the online delivery of courses, we are updating the paper with suggestions on how students can complete the fly trap experiment from home. Traps are made with common items and baited with materials found in most kitchens and placed near open windows for up to five days during temperate seasons. Students are encouraged to creatively modify trap designs and baits based on their resources. Students then count and record the number of flies captured in each trap/bait combination and share their data across the class to create a large data set to analyse and explore for trends. Online video conferencing platforms, such as Zoom, can be used before and after the experiment to facilitate group discussion and maintain student engagement. Datasets can also be pooled across classes and we have included a sample dataset created through a Twitter callout for participants. The experiment is easily adaptable to allow students to have a valuable hands-on experience with experimental design, data collection, data analysis, and effective peer communication without leaving their own home.<!--pagebreak--> <em>Primary image:&nbsp;</em>Fly trap experiment using common household items. From left to right, the plastic wrap trap with red wine, the plastic wrap trap with mashed banana, the paper funnel trap with red wine, and the paper funnel trap with mashed banana. Original published lesson:&nbsp;<a href="https://doi.org/10.24918/cs.2019.35">Gotcha! Which fly trap is the best? An introduction to experimental data collection and analysis</a>

Few-layer Bi2O2CO3 nanosheets derived from electrochemically exfoliated bismuthene for the enhanced photocatalytic degradation of ciprofloxacin antibiotic.

Few-layer two-dimensional (2D) Bi2O2CO3 nanosheets with a thickness of 4–5 nm were successfully fabricated via electrochemical exfoliation, followed by an exposure to ambient conditions. The formation process for these nanosheets was explored through ex situ X-ray diffractometer. The photocatalytic capacity of 2D Bi2O2CO3 nanosheets was investigated towards the degradation of ciprofloxacin. It was shown that 2D Bi2O2CO3 nanosheets exhibited better catalytic performance than Bi2O2CO3 nanoparticles synthesized by hydrothermal method under UV-Vis light irradiation. The enhanced photocatalytic activity is due to the larger specific surface area, as well as the lower band gap. Additionally, the radical trap experiments demonstrate that holes and hydroxyl radicals are of great importance in the degradation of ciprofloxacin. Finally, the 2D Bi2O2CO3 nanosheets show high stability in the photocatalytic degradation of ciprofloxacin, and could have a prospective application in the treatment of antibiotic wastewater.

UNDERSTANDING SURF-ZONE HYDRO-MORPHODYNAMIC PROCESSES IN A TYPICAL POCKET BEACH ALONG THE WEST COAST OF INDIA

Coastal processes are natural processes that operate along coastal zones, resulting in morphological changes in erosion and deposition. The western coast of India is affected by extreme monsoonal wave activity, which can lead to the loss of beaches and the vulnerability of the dunes. As a result, understanding actual near-shore physics and long-shore sediment transport becomes a prerequisite for the development of an effective coastal zone management strategy. The aim of this study is to quantify and investigate longshore sediment flux as a result of wave action based on sediment trap experiments (Kraus 1987). The Kraus (1987) method, along with wave hydrodynamics and current measurements, is performed using acoustic instruments across the surf zone.

Changes in the recovery of insects in pitfall traps associated with the age of cow dung bait fresh or frozen at the time of placement.

Pitfall traps baited with cattle dung are commonly used to characterize local assemblages of coprophilous insects. Baits can be made fresh or be prepared in advance and kept frozen until needed. Insect recoveries are expected to decline with the age of the bait and may be affected by the use of fresh vs. frozen baits. To assess the effect of these two factors on insect recoveries, we performed a pitfall trap experiment that was repeated in four trials spanning 2 years and two locations in southern Alberta, Canada. The experimental design allowed us to minimize the potential confounding effect of short-term weather events. For results combined across trials, baits aged >3 days were largely ineffective for attracting coprophilous species. Frozen baits attracted significantly more insects than did fresh dung for the first 3 days after placement in the field with no difference thereafter. Our findings suggest that insect recoveries in dung-baited pitfall traps can be maximized with the use of frozen baits with replacement every 3-4 days.

Investigating the influence of silver state on electronic properties of Ag/Ag2O/TiO2 heterojunctions prepared by photodeposition

Two series of Ag-TiO2 photocatalysts were prepared with the use of photodeposition method with variation of the irradiation time and precursor concentration. The obtained photocatalysts were studied by XRD, Raman spectroscopy, HR TEM, UV–vis spectroscopy, and low-temperature N2 adsorption/desorption method. It has been consequently found that the optical properties of the resulting catalysts differ significantly: the positions of surface plasmon resonance peaks red-shifted with the increase in precursor concentration. At the same time, optical absorption of the samples increases with both precursor concentration and irradiation time. Photocatalytic activity for the obtained catalysts was evaluated in decolorization of Rhodamine B with the use of Xe arc lamp (250 W) with and without λ > 420 nm light filter. Radical trap experiments have shown that the amount of both superoxide anions and hydroxyl radicals increased in full spectrum of the lamp, with the latter being absent in the reaction mixture during visible light photocatalysis. Comparison of different Ag-TiO2 catalysts has also been made, with 1-Ag-90 min sample being the most active in full spectrum, and 3-Ag-90 min demonstrating the highest conversion in visible light attributed to the increased generation of superoxide species on the surface of Ag clusters. Controversially, 1-Ag-45 min sample showed the lowest activity in full spectrum being surpassed even by unmodified TiO2, but reached the highest rate constant value in visible light. This effect can be related to advanced electronic interaction between Ag plasmonic nanoparticles and titania support in the presence of sensitizer compound, and the formation of Ag/Ag2O composite system on the surface of titania. Influence of the state of silver on photocatalytic activity and mechanism details is discussed with special attention to irradiation wavelengths.

RPL-4 and RPL-9 ̶Mediated Ribosome Purifications Facilitate the Efficient Analysis of Gene Expression in Caenorhabditis elegans Germ Cells.

In many organisms, tissue complexity and cellular diversity create a barrier that can hinder our understanding of gene expression programs. To address this problem, methods have been developed that allow for easy isolation of translated mRNAs from genetically defined cell populations. A prominent example is the Translating Ribosome Affinity Purification method also called TRAP. Here, ribosome associated mRNAs are isolated via purification of the ribosomal protein RPL10A/uL1, which is expressed under the control of a tissue specific promoter. Originally developed to investigate gene expression in mouse neurons, it has by now been adopted to many different organisms and tissues. Interestingly, TRAP has never been used successfully to analyze mRNA translation in germ cells. Employing a combination of genetic and biochemical approaches, I assessed several ribosomal proteins for their suitability for TRAP using the Caenorhabditis elegans germline as a target tissue. Surprisingly, I found that RPL10A/uL1 is not the ideal ribosomal component to perform such an analysis in germ cells. Instead other proteins such as RPL4/uL4 or RPL9/eL6 are much better suited for this task. Tagged variants of these proteins are well expressed in germ cells, integrated into translating ribosomes and do not influence germ cell functions. Furthermore, germ cell-specific mRNAs are much more efficiently co-purified with RPL4/uL4 and RPL9/uL6 compared to RPL10A/uL1. This study provides a solid basis upon which future germ cell TRAP experiments can be built, and it highlights the need for rigorous testing when adopting such methods to a new biological system.