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On Riemann surfaces MM, there exists a canonical correspondence between a possibly multivalued function ΨX{\Psi }_{X} whose differential is single-valued (i.e. an additively automorphic singular complex analytic function) and a vector field XX. From the point of view of vector fields, the singularities that we consider are zeros, poles, isolated essential singularities, and accumulation points of the above. The theory of singularities of the inverse function ΨX‒1{\Psi }_{X}^{‒1} is extended from meromorphic functions to additively automorphic singular complex analytic functions. The main contribution is a complete characterization of when a singularity of ΨX−1{\Psi }_{X}^{-1} is algebraic, is logarithmic, or arises from a zero with non-zero residue of XX. Relationships between analytical properties of ΨX{\Psi }_{X}, singularities of ΨX−1{\Psi }_{X}^{-1} and singularities of XX are presented. Families and sporadic examples showing the geometrical richness of vector fields on the neighbourhoods of the singularities of ΨX−1{\Psi }_{X}^{-1} are studied. As applications, we have; a description of the maximal univalence regions for complex trajectory solutions of a vector field XX, a geometric characterization of the incomplete real trajectories of a vector field XX, and a description of the singularities of the vector field associated with the Riemann ξ{\rm{\xi }}-function.

Poplar plantations cover 31.4 million ha around the world and supply timber for paper, sawn wood and other wood-based products. In each region where poplars are planted, it is possible to identify “model clones” which are massively adopted by foresters. Improving the rationale of clone selection in breeding programs requires a comprehensive understanding of the physiological traits that explain the differences in genotypes growth. Moreover, given that growth is related to the use of resources (water, light and nutrients) we also need to determine which morphological and physiological traits explain the model condition of most widespread clones. A controlled-condition study was carried out to evaluate eight Populus deltoides and two Populus × canadensis clones, including the model Populus deltoides €˜Australiano 129/60’. For each clone, physiological and morphological traits related to biomass partitioning (roots, stem and leaf dry mass), growth (height, diameter), light use (leaf area duration, leaf size, net photosynthetic rate), water use (stem hydraulic conductivity, water consumption) and nutrient use (nitrogen and phosphorus concentrations) were measured. High variability in the physiology and morphology was observed among clones, and similar and contrasting clones in relation to the model clone were identified. Similarities among clones varied depending on the characteristic being evaluated at the time-water use, light use or nutrient use. The results showed that variability not only relates to visible phenotype, but also to functionality. This information is significant since the breeding programs can evaluate non-traditional traits and select genotypes which are similar or complementary to the model clone. The characterization of model clones is key for breeding programs which seek new candidates taking into account the use of water, nutrients and light. It is also important because it helps explain why foresters prefer one clone over others. Knowledge about functional variability within clones of the same species enables foresters to conduct more intelligent and site-specific silviculture and to optimize the genotype selection in breeding programs.

Serratia marcescens is a global opportunistic pathogen. In vitro cytotoxicity of this bacterium is mainly related to metalloprotease serralysin (PrtS) activity. Proteolytic capability varies among the different isolates. Here, we characterized protease production and transcriptional regulators at 37°C of two S. marcescens isolates from bronchial expectorations, HU1848 and SmUNAM836. As a reference strain the insect pathogen S. marcescens Db10 was included. Zymography of supernatant cultures revealed a single (SmUNAM836) or double proteolytic zones (HU1848 and Db10). Mass spectrometry confirmed the identity of PrtS and the serralysin-like protease SlpB from supernatant samples. Elevated proteolytic activity and prtS expression were evidenced in the HU1848 strain through azocasein degradation and qRT-PCR, respectively. Evaluation of transcriptional regulators revealed higher eepR expression in HU1848, whereas cpxR and hexS transcriptional levels were similar between studied strains. Higher eepR expression in HU1848 was further confirmed through an in vivo transcriptional assay. Moreover, two putative CpxR binding motifs were identified within the eepR regulatory region. EMSA validated the interaction of CpxR with both motifs. The evaluation of eepR transcription in a cpxR deletion strain indicated that CpxR negatively regulates eepR. Sequence conservation suggests that regulation of eepR by CpxR is common along S. marcescens species. Overall, our data incorporates CpxR to the complex regulatory mechanisms governing eepR expression and associates the increased proteolytic activity of the HU1848 strain with higher eepR transcription. Based on the global impact of EepR in secondary metabolites production, our work contributes to understanding virulence factors variances across S. marcescens isolates.

In recent years, advanced oxidation processes (AOPs) based on the generation of sulfate radicals (SO4●-) (SR-AOPs) have emerged as an innovative method for the decontamination of water and wastewater. In this study, Fe(II) and Co(II) catalysts supported on ZrO₂ were synthesized and employed as an activator for PMS and PS for the degradation of methyl orange. The general objective is to gain detailed insight into the interaction between oxidants and supported metal catalysts at the molecular level. Experimental results and density functional theory (DFT) calculations were employed to analyze the potential activation mechanism of the oxidants. The support was prepared via coprecipitation, and metal ion deposition was achieved through incipient wetness impregnation. The characterization of the catalysts was conducted through atomic absorption spectrometry, X-ray diffraction and Fourier-transform infrared spectroscopy. The findings indicated that PMS was the most efficient oxidant, with Co–ZrO2 emerging as the most effective catalyst (77% MO mineralization), compared to Fe–ZrO2, which exhibited a lower degree of mineralization (37.6%) under the specified experimental conditions. The use of PS as an oxidant resulted in low levels of degradation for both catalysts. The remarkable catalytic efficacy of the Co–ZrO₂/PMS system was elucidated through the application of density functional theory (DFT) calculations. These revealed that the adsorption energy of the oxidants on Co–ZrO₂ is lower than that on Fe–ZrO₂, which could facilitate the subsequent release of radicals to the reaction medium.

Hanson Cummings,1,* Moizza Zia Ul Haq,1,* Amne Dargham,1 Nauman Shakeel,1 Jason W Busse,1– 3 Andrea J Darzi,1,3 Elizabeth Alvarez1,4 1Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, Ontario, Canada; 2Michael G DeGroote Centre for Medicinal Cannabis Research, McMaster University, Hamilton, Ontario, Canada; 3Department of Anesthesia, McMaster University, Hamilton, Ontario, Canada; 4Centre for Health Economics and Policy Analysis (CHEPA), McMaster University, Hamilton, Ontario, Canada*These authors contributed equally to this workCorrespondence: Elizabeth Alvarez, Department of Health Research Methods, Evidence and Impact, McMaster University, CRL 2nd Floor, 1280 Main Street West, Hamilton, Ontario, L8S 4K1, Canada, Tel +1 905 525-9140 Ext. 22248, Email alvare@mcmaster.caBackground: Cannabis for medical purposes has been legal in Canada since 2001; however, physicians receive no formal training in this modality, and clinical use of cannabis remains controversial. This study aims to explore the values and preferences of people living with chronic pain (PLwCP) in using medical cannabis for chronic pain to inform guideline development and shared decision-making in clinical practice.Methods: We conducted a descriptive qualitative study using in-depth interviews with PLwCP. Using a deductive/inductive approach, we developed concepts and themes related to values and preferences of PLwCP on their use (or avoidance) of medical cannabis for chronic pain.Results: We interviewed 52 PLwCP, including current medical cannabis users (40), previous users (10) and non-users (2). Most PLwCP who used cannabis therapeutically reported the need for experimentation to determine what cannabis products, routes, and doses worked for them. Perceived benefits of medical cannabis among current users included relief from pain, better sleep, and improved mental health. Reasons for discontinuing use of medical cannabis included lack of improvement in pain or sleep or undesirable side effects. Cannabidiol (CBD) dominant products were reported to result in minimal adverse effects (eg, physical or mental impairment) compared to tetrahydrocannabinol (THC) dominant products. Perceived barriers or facilitators to use included social acceptability, availability or access, cost, and attitudes and knowledge among healthcare providers. Participants noted different routes of cannabis use including oral routes that provided longer-lasting pain relief with a slower onset and inhaled routes with a more rapid onset with shorter-lived effects.Conclusion: Participants’ decisions to use medical cannabis for chronic pain were varied, which suggests these decisions are likely to be sensitive to individuals’ values and preferences. There is a call for further research and information-sharing to help PLwCP understand the complexities of cannabis use for medical purposes, including ideal dosing and timing.Plain Language Summary: In Canada, cannabis for medical reasons has been legal since 2001. It has been used as one of the many strategies for chronic or ongoing pain, but doctors are not given consistent information regarding its use, and existing guidance does not include the patient point of view. We did this study to explore how people living with chronic pain feel about the use of medical cannabis. We asked 52 people living with chronic pain, including current medical cannabis users, previous users, and non-users. We found that many people who used cannabis for their pain had to experiment to determine what cannabis products, routes, and doses worked for them. Benefits of medical cannabis included relief from pain, better sleep, and improved mental health. Reasons for stopping medical cannabis included no to little improvement in pain and/or sleep or the presence of unwanted side effects. Cannabidiol (CBD) products resulted in fewer unwanted effects (eg, physical or mental impairment) compared to tetrahydrocannabinol (THC) products. People discussed different routes of cannabis use including oral routes that provided longer-lasting pain relief but with a slower onset and inhaled routes with a faster onset of relief but with shorter-lived effects. People’s decisions regarding medical cannabis use for chronic pain were varied, suggesting these decisions are likely to be sensitive to individual’s values and preferences. More research is needed to learn what doses, products, and routes work for specific chronic pain conditions.Keywords: medical cannabis, chronic pain, health services, guideline, patient values and preferences, Canada

Pedro Jara-Guajardo,1,2 Francisco Morales-Zavala,1,2 Karen Bolaños,1– 3 Ernest Giralt,4,5 Eyleen Araya,2,6 Gerardo A Acosta,7,8 Fernando Albericio,5,7,9 Alejandra R Alvarez,10 Marcelo J Kogan1,2 1Departamento de Quimica Farmacologica y Toxicologica, Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Santiago, Chile; 2Advanced Center for Chronic Diseases (ACCDiS), Independencia, Santiago, Chile; 3Center for Studies on Exercise, Metabolism and Cancer (CEMC), Laboratory of Cellular Communication, Program of Cell and Molecular Biology, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), University of Chile, Santiago, Chile; 4Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain; 5Department of Inorganic and Organic Chemistry, University of Barcelona, Barcelona, Spain; 6Departamento de Ciencias Quimicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Santiago, Chile; 7CIBER-BBN, Networking Centre on Bioengineering, Biomaterials and Nanomedicine & Department of Organic Chemistry, University of Barcelona, Barcelona, Spain; 8Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona, 08034, Spain; 9School of Chemistry & Physics, University of KwaZulu-Natal, Durban, South Africa; 10Cell Signaling Laboratory, Department of Cellular and Molecular Biology, Biological Sciences Faculty, Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, ChileCorrespondence: Alejandra R Alvarez; Marcelo J Kogan, Email aalvarez@bio.puc.cl; mkogan@ciq.uchile.clIntroduction: The development of new materials and tools for radiology is key to the implementation of this diagnostic technique in clinics. In this work, we evaluated the differential accumulation of peptide-functionalized GNRs in a transgenic animal model (APPswe/PSENd1E9) of Alzheimer’s disease (AD) by computed tomography (CT) and measured the pharmacokinetic parameters and bioaccumulation of the nanosystem.Methods: The GNRs were functionalized with two peptides, Ang2 and D1, which conferred on them the properties of crossing the blood-brain barrier and binding to amyloid aggregates, respectively, thus making them a diagnostic tool with great potential for AD. The nanosystem was administered intravenously in APPswe/PSEN1dE9 model mice of 4-, 8- and 18-months of age, and the accumulation of gold nanoparticles was observed by computed tomography (CT). The gold accumulation and biodistribution were determined by atomic absorption.Results: Our findings indicated that 18-month-old animals treated with our nanosystem (GNR-D1/Ang2) displayed noticeable differences in CT signals compared to those treated with a control nanosystem (GNR-Ang2). However, no such distinctions were observed in younger animals. This suggests that our nanosystem holds the potential to effectively detect AD pathology.Discussion: These results support the future development of gold nanoparticle-based technology as a more effective and accessible alternative for the diagnosis of AD and represent a significant advance in the development of gold nanoparticle applications in disease diagnosis. Keywords: computed tomography, gold nanorods, amyloid-beta, Aβ, Alzheimer’s disease, diagnostic