The international community has recognized the significance of plastic pollution, and there is a growing consensus among governments, organizations, and communities that action is urgently needed. ...The United Nations Environment Assembly's resolution to combat plastic pollution demonstrates the global commitment to tackling this issue. By focusing on plastic pollution, our article aims to contribute to the ongoing efforts to develop policy interventions that align with international commitments and effectively address this pressing environmental challenge. Using the literature review method, this article investigates the world’s plastic interventions to provide contemporary policy perspectives in sustainable plastic waste management. By integrating a comprehensive analysis of an evolving issue from various international perspectives, this article revisits and explores effective solutions to combat plastic pollution. We ask the key question: What are the policy interventions that have changed key stakeholders’ behaviour towards plastics? The analysis reveals five distinct themes in policy interventions that align with the ambitious United Nations Environment Assembly (UNEA) resolution to end plastic pollution: (1) Addressing the plastic waste with regulations, (2) Collective responsibilities in plastic reduction, (3) Concerns in waste management and collection, (4) Enhancing collection efforts through education, and (5) The importance of technology to end plastic pollution. We conclude with remarks on the importance of integrated approaches to the entire plastic life cycle from the beginning of its production to the end users in order to end plastic pollution.
Currently, the most popular molecular photosensitizers used for synthetic organic chemistry and energy applications are still the noble-metal-based ruthenium and iridium complexes that usually ...require expensive metal and ligand precursors. In contrast, bis(arylimino)acenaphthene (Ar-BIAN) is an established redox noninnocent π-accepting ligand that is easily assembled in one condensation step from affordable and commercially available precursors. Herein, we have developed a series of Ar-BIAN CuI complexes as visible-light-harvesting photosensitizers. Notably, one of these panchromatic, homoleptic Ar-BIAN CuI complexes exhibits a radiative recombination lifetime that is longer than diffusion-controlled reactions, as observed by time-correlated single-photon counting spectroscopy. Ar-BIAN CuI facilitates visible-light-promoted atom-transfer radical addition reactions via carbon–carbon bond formation with CBr3 radicals in good yields of up to 75%. Steady-state and transient absorption spectroscopic measurements, together with spectroelectrochemical experiments and intermediate isolation studies, were performed to obtain insights into this photoredox catalysis and provide guidelines for the general deployment of Ar-BIAN CuI photosensitizers in synthetic organic chemistry and renewable energy applications.
We describe an efficient high-throughput method for accurate DNA sequencing of entire cDNA clones. Developed as part of our involvement in the Mammalian Gene Collection full-length cDNA sequencing ...initiative, the method has been used and refined in our laboratory since September 2000. Amenable to large scale projects, we have used the method to generate >7 Mb of accurate sequence from 3695 candidate full-length cDNAs. Sequencing is accomplished through the insertion of Mu transposon into cDNAs, followed by sequencing reactions primed with Mu-specific sequencing primers. Transposon insertion reactions are not performed with individual cDNAs but rather on pools of up to 96 clones. This pooling strategy reduces the number of transposon insertion sequencing libraries that would otherwise be required, reducing the costs and enhancing the efficiency of the transposon library construction procedure. Sequences generated using transposon-specific sequencing primers are assembled to yield the full-length cDNA sequence, with sequence editing and other sequence finishing activities performed as required to resolve sequence ambiguities. Although analysis of the many thousands (22 785) of sequenced Mu transposon insertion events revealed a weak sequence preference for Mu insertion, we observed insertion of the Mu transposon into 1015 of the possible 1024 5mer candidate insertion sites.
Expansion of polyglutamine-encoding CAG trinucleotide repeats has been identified as the pathogenic mutation in nine different genes associated with neurodegenerative disorders. The majority of ...individuals clinically diagnosed with spinocerebellar ataxia do not have mutations within known disease genes, and it is likely that additional ataxias or Huntington disease-like disorders will be found to be caused by this common mutational mechanism. We set out to determine the length distributions of CAG-polyglutamine tracts for the entire human genome in a set of healthy individuals in order to characterize the nature of polyglutamine repeat length variation across the human genome, to establish the background against which pathogenic repeat expansions can be detected, and to prioritize candidate genes for repeat expansion disorders.
We found that repeats, including those in known disease genes, have unique distributions of glutamine tract lengths, as measured by fragment analysis of PCR-amplified repeat regions. This emphasizes the need to characterize each distribution and avoid making generalizations between loci. The best predictors of known disease genes were occurrence of a long CAG-tract uninterrupted by CAA codons in their reference genome sequence, and high glutamine tract length variance in the normal population. We used these parameters to identify eight priority candidate genes for polyglutamine expansion disorders. Twelve CAG-polyglutamine repeats were invariant and these can likely be excluded as candidates. We outline some confusion in the literature about this type of data, difficulties in comparing such data between publications, and its application to studies of disease prevalence in different populations. Analysis of Gene Ontology-based functions of CAG-polyglutamine-containing genes provided a visual framework for interpretation of these genes' functions. All nine known disease genes were involved in DNA-dependent regulation of transcription or in neurogenesis, as were all of the well-characterized priority candidate genes.
This publication makes freely available the normal distributions of CAG-polyglutamine repeats in the human genome. Using these background distributions, against which pathogenic expansions can be identified, we have begun screening for mutations in individuals clinically diagnosed with novel forms of spinocerebellar ataxia or Huntington disease-like disorders who do not have identified mutations within the known disease-associated genes.
A physical map of the mouse genome Bentley, David R; Gregory, Simon G; Sekhon, Mandeep ...
Nature (London),
08/2002, Letnik:
418, Številka:
6899
Journal Article
Recenzirano
A physical map of a genome is an essential guide for navigation, allowing the location of any gene or other landmark in the chromosomal DNA. We have constructed a physical map of the mouse genome ...that contains 296 contigs of overlapping bacterial clones and 16,992 unique markers. The mouse contigs were aligned to the human genome sequence on the basis of 51,486 homology matches, thus enabling use of the conserved synteny (correspondence between chromosome blocks) of the two genomes to accelerate construction of the mouse map. The map provides a framework for assembly of whole-genome shotgun sequence data, and a tile path of clones for generation of the reference sequence. Definition of the human-mouse alignment at this level of resolution enables identification of a mouse clone that corresponds to almost any position in the human genome. The human sequence may be used to facilitate construction of other mammalian genome maps using the same strategy.
Plastics have become indispensable in our daily lives, but plastic waste has proliferated in landfills and oceans since most plastics are non-biodegradable and cannot be mechanically recycled. ...Existing chemical recycling processes such as pyrolysis and hydrogenolysis typically use high temperatures, generate unnecessary greenhouse gas emissions, often require expensive noble metals, and show limited generality. In addition, the latest efforts in the photochemical upcycling of plastics near ambient temperatures are mainly restricted to polystyrene. Here, we report a base metal photo-driven upcycling of most conventional plastics such as polystyrene, polypropylene, polyethylene, polyvinyl chloride, and polyvinyl acetate by a tandem carbon–hydrogen bond oxidation/carbon–carbon bond cleavage reaction, with carbon recoveries up to 77% and selective formation of valuable, isolable products including formic, acetic, and benzoic acids. We successfully applied the optimized ambient conditions on copolymers, multilayered packaging, and actual plastic waste. Gram-scale reactions were demonstrated using a flow photoreactor with recirculation.
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•Non-biodegradable plastics of resin codes 2–7 and multilayered packaging are upcycled•Visible light as energy source with affordable, commercial base metal photocatalyst•Scalable flow reactions under ambient conditions to minimize greenhouse gas emissions•Isolable yields of carboxylic acid platform chemicals and liquid organic H2 carriers
Globally, only around 9% of plastic waste is currently recycled, leaving a staggering 91% in landfills, incinerators, or discarded into the environment. The majority of the unrecycled plastics consist of non-biodegradable polyolefins, such as polyethylene and polypropylene commonly used in packaging materials due to their long lifespans, which pose significant challenges to their waste management. Traditional methods like high-temperature pyrolysis require heating to at least 200°C, which unnecessarily emits considerable amounts of greenhouse gases. Herein, we report a photocatalytic reaction that can upcycle plastics into platform chemicals at ambient temperature and pressure. The products include carboxylic acids that are versatile precursors and can be used for energy storage as liquid organic hydrogen carriers. This work establishes the viability of “mining” plastic waste as a sustainable alternative to fossil fuels for energy generation and the production of chemical feedstocks.
Over 90% of globally produced plastics have accumulated as pollutants in the environment because most of them are not biodegradable. Existing methods to recycle plastic waste require heat and generate more greenhouse gas emissions. We present a general method to upcycle most plastics of resin codes 2–7, multilayered packaging, and oil-contaminated packaging into platform chemicals and fuels to improve plastics circularity. The reactions are conducted at ambient conditions and driven by light using an affordable, commercially sourced base metal photocatalyst.
The hybridization patterns of 18,371 high-density-grid-arrayed non-redundant complementary DNA (cDNA) clones were examined using three different sources of cDNA probes. The first set of probes was ...synthesized from mRNA isolated from visual brain areas MT and V4 of Vervet monkey. The second set of probes was derived from cDNA libraries constructed from two micro dissected sets of layers of the monkey
L
ateral
G
eniculate
N
ucleus layers within the visual pathway, namely the magnocellular and parvocellular layers. The third set of cDNA probes was synthesized from the subtracted fractions of the cDNAs enriched for either the magnocellular or the parvocellular layers of the Lateral Geniculate Nucleus. Software, linked directly to the Genbank database, was developed to aid in the rapid identification of both expressed and differentially expressed genes. Our results indicate that both the cDNA probes synthesized from mRNA and cDNA libraries can identify similar fractions of expressed genes. However, the subtracted cDNA probes improve the efficiency of detection for those genes that are expressed at much lower abundance. Analyses of these results for the differential expression patterns of these genes were validated by semi-quantitative PCR on the DNA derived from the whole tissue cDNA libraries. A list of some known genes that are statistically differentially expressed within the magnocellular layers of the LGN and area MT in the primate visual areas is derived.
Ion channels have been identified as therapeutic targets in various disorders, such as cardiovascular disease, neurological disease, and cystic fibrosis. Flux assays to detect functional ionic flux ...through ion channels are becoming increasingly popular as tools for screening compounds. In an optimized flux assay, modulation of ion channel activity may produce readily detectable changes in radiolabeled or nonradiolabeled ionic flux. Technologies based on flux assays are currently available in a fully automated high throughput format for efficient screening. This application offers sensitive, precise, and reproducible measurements giving accurate drug rank orders matching those of patch clamp data. Conveniently, the flux assay is amenable to adaptation for different ion channels, such as potassium, sodium, calcium, and chloride channels, by using suitable tracer ions. The nonradiolabeled rubidium-based flux assay coupled with the ion channel reader (ICR) technology has become very successful in ion channel activity analysis and is emerging as a popular technique in modern drug discovery.
S. haemolyticus is emerging as an important nosocomial pathogen. In spite of its
increasing importance, the exact incidence of infections is still unknown due to the lack
of accurate identification ...methods. Therefore, part of this thesis involves the evaluation
of a novel identification method for S. haemolyticus based on the HSP60 gene. The
HSP60 gene is ubiquitous and highly conserved among staphylococci, but still contains
species-specific signature sequences which may be useful for species identification of
staphylococci. To evaluate the specificity and sensitivity of the HSP60 method, HSP60
probes were generated from reference strains of S. haemolyticus (ATCC29970) and S.
epidermidis (ATCC14990) for use in dot blot hybridization reactions with a collection of
66 consecutive bacteremic isolates of CNS, previously identified by the Microscan
method and confirmed by BCCDC. The hybridization results were further compared to
the API Staph method. The results were as follows: Table
The HSP60 method was highly accurate for the species identification of both S.
haemolyticus and S. epidermidis, while the Microscan method lacked specificity and the
API method lacked sensitivity. Therefore the HSP60 gene is an excellent target for the
species identification of S. haemolyticus. The second part of the thesis involved
elucidating the mechanism of vancomycin resistance in S. haemolyticus, for which little
is known. The incidence of vancomycin resistance was examined among the 66 isolates
of CNS mentioned earlier. All but one isolate (B7786), a S. haemolyticus, was sensitive
to vancomycin (MIC below 2 ug/ml). This isolate displayed intermediate resistance to
vancomycin (MIC 4ug/ml). Population analysis of B7786, however, yielded a highly
resistant and stable subpopulation (128G₅) (MIC 32 ug/ml; selection frequency 10⁻⁷). The
resistant phenotype was characterized by comparing its biochemical, antibiotic,
cytoplasmic and cell membrane proteins and vancomycin binding profiles with the parent
isolate. While no significant differences were revealed in the biochemical and
cytoplasmic protein profiles of I28G₅ compared to its parent, two membrane proteins, 44
kDa and 30 kDa, were observed to be downregulated and upregulated, respectively. The
antibiotic profiles with ceftriazone, cefotaxime, tobramycin and amikacin were also
dramatically decreased in I28G₅; pointing to an altered cell membrane. Furthermore,
competition studies of I28G₅ with isoglutaminyl-D-alanine-D-alanine demonstrated a 16-
fold increase in its vancomycin MIC with no effect on the parent; suggesting an altered
resistant cell wall. Scatchard plots from saturation binding studies with ¹²⁵I⁻labeled
vancomycin confirmed that I28G5 had an altered cell wall with 4-fold more receptors -
than B7786 (23,790 nM vs 5,504nM per 10⁷ cells). However, only one type of receptors
with similar affinity constants (Kd approximately 1 nM) for both the resistant phenotype and the parent were found. SEM and T EM revealed the reason for the greater number of
receptors. The resistant cells had 60% larger diameters, four-fold thicker cell walls and
poorly divided daughter cells with apparent missing splitting systems compared to the
parent. Taken together, these data suggest that the resistant phenotype is associated with a
defect in cell wall division, synthesis and turnover. We postulate that this defect results in
an abnormally thickened cell wall with abundant cell wall material which can "mop" up
vancomycin in the medium, reduce the its availability to the active sites
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