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1.
Science ; 384(6701): 1235-1240, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38870279

ABSTRACT

Zinc (Zn) is vital to marine organisms. Its active uptake by phytoplankton results in a substantial depletion of dissolved Zn, and Zn bound to particulate organic matter replenishes dissolved Zn in the ocean through remineralization. However, we found that particulate Zn changes from Zn bound to phosphoryls in cells to recalcitrant inorganic pools that include biogenic silica, clays, and iron, manganese, and aluminum oxides in the Southern Ocean water column. The abundances of inorganic pools increase with depth and are the only phases preserved in sediments. Changes in the particulate-Zn speciation influence Zn bioavailability and explain the decoupling of Zn and phosphorus and the correlation of Zn and silicon in the water column. These findings reveal a new dimension to the ocean Zn cycle, implicating an underappreciated role of inorganic Zn particles and their impact on biological productivity.

3.
Int J Biol Macromol ; 260(Pt 2): 129579, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38266852

ABSTRACT

High Energy Ball-Milling (HEBM) modifies starchs' granule morphology, physicochemical properties, and chemical structure. However, understanding how the HEBM changes the starch chemical structure is necessary to control these modifications. Therefore, this study aimed to investigate the changes in potato starch's long- and short-range molecular order during HEBM at different environmental conditions such as oxygen (Air) and humidity content. Due to the correlation between the starch modification and the energy supplied (Esupp) by the HEBM, Burgio's equation was used to calculate this energy. The starch transformation was followed by X-ray diffraction, Fourier Transform-Infrared Spectroscopy, and Raman spectroscopy. A Principal Component Analysis (PCA) was conducted to reduce the HEBM variables. PAC analysis demonstrated that the different oxygen-humidity conditions do not affect the HEBM of potato starch. Based on the starch chemical structure transformation correlated with Esupp during HEBM, four stages were observed: orientation, modification, mechanolysis, and over-destruction. It was identified for the first time that at low milling energy (<1.5 kJ/g, orientation stage), the glycosidic rings change their orientation, and starch-water interaction increases while the starch's organization reduces. Ergo, the potato starch could be more susceptible to chemical modifications during the first two stages.


Subject(s)
Solanum tuberosum , Solanum tuberosum/chemistry , Amylose/chemistry , Humidity , Oxygen , Starch/chemistry , X-Ray Diffraction
11.
J Phys Chem C Nanomater Interfaces ; 127(48): 23303-23311, 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-38352239

ABSTRACT

In the field of molecular electronics, especially in quantum transport experiments, determining the geometrical configurations of a single molecule trapped between two electrodes can be challenging. To address this challenge, we employed a combination of molecular dynamics (MD) simulations and electronic transport calculations based on density functional theory to determine the molecular orientation in our break-junction experiments under ambient conditions. The molecules used in this study are common solvents used in molecular electronics, such as benzene, toluene (aromatic), and cyclohexane (aliphatic). Furthermore, we introduced a novel criterion based on the normal vector of the surface formed by the cavity of these ring-shaped monocyclic hydrocarbon molecules to clearly define the orientation of the molecules with respect to the electrodes. By comparing the results obtained through MD simulations and density functional theory with experimental data, we observed that both are in good agreement. This agreement helps us to uncover the different geometrical configurations that these molecules adopt in break-junction experiments. This approach can significantly improve our understanding of molecular electronics, especially when using more complex cyclic hydrocarbons.

15.
BMC Cancer ; 21(1): 805, 2021 Jul 13.
Article in English | MEDLINE | ID: mdl-34256713

ABSTRACT

BACKGROUND: Cancerous cells can recycle metabolic ammonium for their growth. As this ammonium has a low nitrogen isotope ratio (15N/14N), its recycling may cause cancer tissue to have lower 15N/14N than surrounding healthy tissue. We investigated whether, within a given tissue type in individual mice, tumoral and healthy tissues could be distinguished based on their 15N/14N. METHODS: Micro-biopsies of murine tumors and adjacent tissues were analyzed for 15N/14N using novel high-sensitivity methods. Isotopic analysis was pursued in Nude and C57BL/6 mice models with mature orthotopic brain and head&neck tumors generated by implantation of H454 and MEERL95 murine cells, respectively. RESULTS: In the 7 mice analyzed, the brain tumors had distinctly lower 15N/14N than healthy neural tissue. In the 5 mice with head&neck tumors, the difference was smaller and more variable. This was at least partly due to infiltration of healthy head&neck tissue by tumor cells. However, it may also indicate that the 15N/14N difference between tumoral and healthy tissue depends on the nitrogen metabolism of the healthy organ in question. CONCLUSIONS: The findings, coupled with the high sensitivity of the 15N/14N measurement method used here, suggest a new approach for micro-biopsy-based diagnosis of malignancy as well as an avenue for investigation of cancer metabolism.


Subject(s)
Biopsy/methods , Brain/physiopathology , Head and Neck Neoplasms/physiopathology , Nitrogen Isotopes/metabolism , Animals , Case-Control Studies , Disease Models, Animal , Humans , Mice , Mice, Nude
16.
Climacteric ; 24(1): 46-50, 2021 02.
Article in English | MEDLINE | ID: mdl-32705895

ABSTRACT

The physiological, clinical and therapeutic aspects of testosterone in women's health are still a matter of controversy and debate. Quality evidence data of clinical trials favors the use of transdermal testosterone in postmenopausal women with female sexual dysfunction causing distress. Doses of testosterone should approximate physiological testosterone levels found in premenopausal women, avoiding supraphysiological concentrations that expose women to adverse events. Short-term treatment periods have been shown to be effective and safe in postmenopausal women with hypoactive sexual desire disorder/dysfunction. However, long-term safety of testosterone use must be determined.


Subject(s)
Hormone Replacement Therapy , Postmenopause , Sexual Dysfunctions, Psychological/drug therapy , Testosterone/therapeutic use , Administration, Cutaneous , Female , Humans , Testosterone/administration & dosage
17.
BMC Med Inform Decis Mak ; 20(1): 96, 2020 05 25.
Article in English | MEDLINE | ID: mdl-32450866

ABSTRACT

BACKGROUND AND GOAL: Health information systems are increasingly sophisticated and developing them is a challenge for software developers. Software engineers usually make use of UML as a standard model language that allows defining health information system entities and their relations. However, working with health system requires learning HL7 standards, that defines and manages standards related to health information systems. HL7 standards are varied, however this work focusses on v2 and v3 since these are the most used one on the area that this work is being conducted. This works aims to allow modeling HL7 standard by using UML. METHODS: Several techniques based on the MDE (Model-Driven Engineering) paradigm have been used to cope with it. RESULTS: A useful reference framework, reducing final users learning curve and allowing modeling maintainable and easy-going health information systems. CONCLUSIONS: By using this approach, a software engineer without any previous knowledge about HL7 would be able to solve the problem of modeling HL7-based health information systems. Reducing the learning curve when working in projects that need HL7 standards.


Subject(s)
Health Information Systems , Software , Computer Simulation , Humans , Language
18.
Sci Total Environ ; 717: 137223, 2020 May 15.
Article in English | MEDLINE | ID: mdl-32062239

ABSTRACT

The efficiency of two large-volume batch solar reactors [Prototype I (140 L) and II (88 L)] in treating rainwater on-site in a local informal settlement and farming community was assessed. Untreated [Tank 1 and Tank 2-(First-flush)] and treated (Prototype I and II) tank water samples were routinely collected from each site and all the measured physico-chemical parameters (e.g. pH and turbidity, amongst others), anions (e.g. sulphate and chloride, amongst others) and cations (e.g. iron and lead, amongst others) were within national and international drinking water guidelines limits. Culture-based analysis indicated that Escherichia coli, total and faecal coliforms, enterococci and heterotrophic bacteria counts exceeded drinking water guideline limits in 61%, 100%, 45%, 24% and 100% of the untreated tank water samples collected from both sites. However, an 8 hour solar exposure treatment for both solar reactors was sufficient to reduce these indicator organisms to within national and international drinking water standards, with the exception of the heterotrophic bacteria which exceeded the drinking water standard limit in 43% of the samples treated with the Prototype I reactor (1 log reduction). Molecular viability analysis subsequently indicated that mean overall reductions of 75% and 74% were obtained for the analysed indicator organisms (E. coli and enterococci spp.) and opportunistic pathogens (Klebsiella spp., Legionella spp., Pseudomonas spp., Salmonella spp. and Cryptosporidium spp. oocysts) in the Prototype I and II solar reactors, respectively. The large-volume batch solar reactor prototypes could thus effectively provide four (88 L Prototype II) to seven (144 L Prototype I) people on a daily basis with the basic water requirement for human activities (20 L). Additionally, a generic Water Safety Plan was developed to aid practitioners in identifying risks and implement remedial actions in this type of installation in order to ensure the safety of the treated water.

19.
Acta ortop. mex ; 33(6): 391-394, nov.-dic. 2019. tab, graf
Article in Spanish | LILACS | ID: biblio-1345067

ABSTRACT

Resumen: Introducción: Existen múltiples métodos e implantes utilizados para la artrodesis metatarsofalángica del hallux sin evidencia a favor de uno u otro en la bibliografía. El objetivo fue comparar los resultados clínicos y radiológicos de dos métodos e implantes utilizados en nuestro centro. Material y métodos: Revisión retrospectiva de 37 pies entre 2013 y 2017 (22 pies mediante placa y 15 mediante tornillos canulados). Se recogieron variables clínicas y radiológicas y se aplicaron las escalas AOFAS y Manchester-Oxford. Se estudiaron las variables descriptivas y analíticamente mediante el programa SPSS v15. Resultados: El grupo intervenido mediante placa lo compuso 77% de mujeres, con una edad media de 65 años y una distribución por diagnósticos de hallux valgus (HV) severo (36%), recidiva de hallux valgus (RHV) (36%) y hallux rigidus (HR) (28%), frente a 80% de mujeres, con media de 68 años y HVS (34%), RHV (46%) y HR (20%) en el grupo de tornillos canulados. No se encontró diferencias significativas en la corrección de los ángulos para HVS o RHV. La tasa de seudoartrosis dolorosa fue de 13% en ambos y la reintervención fue de 18% en el grupo de placas y 26% en el grupo de tornillos. Tanto la escala AOFAS como la M-O fueron mejores en el grupo de placa 63.8 versus 52.6 (p = 0.07); 30.1 versus 41.0 (p = 0.10); así como la satisfacción del paciente 86 versus 66% (p > 0.05) y el dolor postoperatorio 3.68 versus 5.58 (p > 0.05). Conclusión: Son grupos pequeños de estudio, sin aleatorización de implantes, ambas opciones son funcionales sin poder encontrar una preferente.


Abstract: Introduction: There are multiple methods and implants used for the metatarsophalangeal arthrodesis of hallux without evidence in favor of one or the other in the bibliography. The goal was to compare the clinical and radiological results of 2 methods and implants used in our center. Material and methods: Retrospective review of 37 feet between 2013 and 2017 (22 feet by plate and 15 by cannulated screws). Clinical and radiological variables were collected and the AOFAS and Manchester-Oxford scales were applied. Variables were studied descriptively and analytically through the SPSSv15 program. Results: The group intervened by plate was composed of 77% of women, with an average age of 65 years and a distribution by diagnosis of severe hallux valgus (HV) (36%), hallux valgus relapse (HVR) (36%) and hallux rigidus (HR) (28%), compared to 80% of women, 68 years old and HV (34%), HVR (46%) HR (20%) in the group of cannulated screws. No significant differences were found in the correction of angles for HV or HVR. The rate of painful pseudoarthrosis was 13% in both and the re-intervention was 18% in the plate group and 26% in the screw group. Both the AOFAS and M-O scales were better in the plate group 63.8 vs 52.6 (p = 0.07); 30.1 vs 41.0 (p = 0.10); as well as patient satisfaction 86% vs 66% (p > 0.05) and postoperative pain 3.68 vs 5.58 (p > 0.05). Conclusion: Small study groups, not implant randomization, both options are functional without being able to find a preferred one.


Subject(s)
Humans , Female , Aged , Hallux , Hallux Valgus , Hallux Rigidus , Metatarsophalangeal Joint , Arthrodesis , Bone Screws , Retrospective Studies , Treatment Outcome
20.
Stud Health Technol Inform ; 264: 758-762, 2019 Aug 21.
Article in English | MEDLINE | ID: mdl-31438026

ABSTRACT

Management of the complex chronically ill patient is highly problematic. This is due to the need to complement recommendations in clinical guidelines with recommendations based on treatments performed on a representative set of patients. It is necessary to identify conflicts between the recommendations of different guidelines designed for handling specific chronic diseases. The PITeS-TIiSS project (code PI15/01213) aims to overcome this problem by designing and deploying an ontology-based personalized clinical decision support tool. This helps to improve personalized decisions and reduces variability in clinical practice in an integrated care environment. This paper describes the methodology followed in developing the ontology used to infer clinical knowledge and to develop and implement the support tool. The tool will access the information provided by the Electronic Health Record of Andalusian Health Public Service, the main healthcare provider in a region in Spain with more than eight million inhabitants.


Subject(s)
Decision Support Systems, Clinical , Chronic Disease , Electronic Health Records , Humans , Software , Spain
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