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1.
Heliyon ; 9(5): e16043, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37206052

RESUMO

Coal has been a valuable natural resource for Mexico not just for its relative abundance but for its critical role in the development of the steel and energy industries. It has been also important in the socioeconomic context of the northeast of the country. However, since years ago, coal mining is facing a transition due to the emergence of new energy sources and the public concern about global warming. A brief review on coal reserves, production and possible non-power uses was carried out to provide insight on the reserves in a global context, extraction patterns and alternatives that the Mexican coal industry has to evolve. For this purpose, Mexican coal reserves were overviewed and contextualized at a global level and total coal production figures from 1970 to 2021 were analyzed to identify fluctuations and differences in the amounts produced between coking and non-coking coal. Further, rare earth elements, carbon fiber and humic acid from coal were briefly reviewed with the aim of initiating a debate on the high value-added products that can be obtained and the technologies that can be adopted to develop the coal industry of Mexico. Coal proven reserves in Mexico are of 1211 million tonnes and, from 1970 to 2021, 428.11 million tonnes have been produced. Of the total cumulative production, 68.8% corresponds to non-coking coal and 31.2% to coking coal.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35810092

RESUMO

INTRODUCTION AND AIM: Intussusception is rare in adults and can occur in the small bowel and colon. Its atypical presentation makes the diagnosis difficult. The aim of the present study was to evaluate the causes, clinical characteristics, and treatment outcomes of adult intussusception and to determine whether there was an association between etiology and clinical presentation. MATERIALS AND METHODS: A retrospective study was carried out on patients above 18 years of age that were treated for intussusception at a tertiary care hospital, between 2000 and 2020. The findings were summarized utilizing descriptive and inferential statistics. RESULTS: Twenty-eight cases were identified. Median patient age was 46 years (18-80) and median symptom duration was 18 days. Abdominal pain was the most frequent symptom (96.42%). The intussusceptions registered were enteroenteric (14), ileocecal (4), ileocolonic (4), colocolonic (5), and colorrectal (1). Intussusception etiology was benign in 15 cases, 9 were associated with malignancy, and 4 were idiopathic. Surgery was performed on 11 patients with enteroenteric intussusception and on all the cases of ileocecal, ileocolonic, colocolonic, and colorectal intussusception. There were 2 events of perioperative mortality (8%) and 8 of postoperative morbidity (32%). No significant differences were found regarding symptom duration or length of hospital stay, when the etiologic groups were compared. CONCLUSIONS: Intussusception is rare in adults. Diagnosis is a challenge because of the nonspecific signs and symptoms. Surgical resection should be considered in the definitive treatment and management should be individualized according to the patient's comorbidities, clinical presentation, and risk of malignancy.

3.
Data Brief ; 41: 107855, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35128008

RESUMO

It is necessary to simulate the thermodynamics of the Te/TeO2-CN-H2O systems to interpret the dissolution behaviour of elemental tellurium and tellurium dioxide in alkaline cyanide solutions. Below are the data employed to simulate the equilibrium diagrams presented in the article entitled "Dissolution behaviour of elemental tellurium and tellurium dioxide in alkaline cyanide solutions". Most of the reactions are available in the Hydra database of MEDUSA© software along with their logarithms to the base 10 of the equilibrium constants (i.e., log K). However, it was complemented with the log K of some important reactions (e.g., which describes the formation of H2TeO3). Log K values were calculated form the ΔG°f reported in the scientific literature. The databases reported can be used to compare the equilibrium constant values, replicate the diagrams presented in the cited article, and simulate other aqueous systems (e.g., those employing alternative lixiviant agents as thiosulfate, thiourea, etc.).

4.
Environ Pollut ; 271: 116380, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33387779

RESUMO

A vast amount of evidence indicates that bisphenol A (BPA) and phthalates are widely distributed in the environment since these compounds are mass-produced for the manufacture of plastics and plasticizers. These compounds belong to a large group of substances termed endocrine-disrupting chemicals (EDC). It is well known that humans and living organisms are unavoidably and unintentionally exposed to BPA and phthalates from food packaging materials and many other everyday products. BPA and phthalates exert their effect by interfering with hormone synthesis, bioavailability, and action, thereby altering cellular proliferation and differentiation, tissue development, and the regulation of several physiological processes. In fact, these EDC can alter fetal programming at an epigenetic level, which can be transgenerational transmitted and may be involved in the development of various chronic pathologies later in the adulthood, including metabolic, reproductive and degenerative diseases, and certain types of cancer. In this review, we describe the most recent proposed mechanisms of action of these EDC and offer a compelling selection of experimental, epidemiological and clinical studies, which show evidence of how exposure to these pollutants affects our health during development, and their association with a wide range of reproductive, metabolic and neurological diseases, as well as hormone-related cancers. We stress the importance of concern in the general population and the urgent need for the medical health care system to closely monitor EDC levels in the population due to unavoidable and involuntary exposure to these pollutants and their impact on human health.


Assuntos
Disruptores Endócrinos , Exposição Ambiental , Adulto , Compostos Benzidrílicos/toxicidade , Política de Saúde , Humanos , Fenóis/toxicidade
5.
Acta Endocrinol (Buchar) ; 17(4): 440-448, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35747853

RESUMO

Context: Different polymorphisms of the endothelial nitric oxide synthase gene (NOS3) have been related to diabetic kidney disease. Objective: To evaluate the association between advanced diabetic chronic kidney disease (ACKD) and the rs1799983 and rs2070744 poymorphisms of NOS3 in a population from the Gran Canaria island. Design: Cross-sectional case-control study. Subjects and methods: Polymorphisms were genotyped in 152 subjects with ACKD secondary to type 2 diabetes [estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2], 110 subjects with type 2 diabetes for 20 or more years since diagnosis without ACKD (eGFR ≥45 mL/min/1.73m2 and albumin/creatinine ratio <300 mg/g and/or 24-h urinary albumin excretion <300 mg) and 292 healthy controls. Association between both polymorphisms and established coronary heart disease (CHD) was also analyzed in both groups with diabetes. Results: A greater proportion of homozygous individuals for the risk allele C of rs2070744 was found among subjects with ACKD. Association between ACKD and rs2070744 was observed in a recessive genetic model, both for comparison to subjects with diabetes but no ACKD [OR 2.17 (95% CI: 1.17-4.00), p=0.014] and for comparison to healthy controls [OR 1.61 (1.03-2.52), p=0.036]. The frequency of the C allele was significantly higher among subjects with CHD, but only in the group with ACKD. No associations were found for rs1799983. Conclusions: NOS3 rs2070744 is associated with ACKD in population with type 2 diabetes from Gran Canaria. A link between this genetic variant and CHD in Canarian subjects with type 2 diabetes could be restricted to cases with ACKD.

7.
G Chir ; 41(1): 5-17, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32038008

RESUMO

Bariatric surgery was introduced in 1953, but during the last 20 years its popularity has increased after the development of significant Romaevidenced based breakthroughs in the field. Currently, approximately 150 long-term randomized clinical trials and 40 meta-analyses support and give credibility to the surgical approaches for the treatment of obesity and its related metabolic disturbances. Bariatric surgery has demonstrated improved outcomes compared to medical treatment, conduct therapy, and endoscopic procedures. Roux-en-Y gastrojejunostomy (RYGB) and Sleeve gastrectomy (SG) are the surgical procedures most frequently performed, due to their satisfactory results and security profile. There is sufficient evidence in medical literature to perform these procedures when indicated; however, there are still several controversies regarding technical aspects that need to be further explored.


Assuntos
Gastrectomia/métodos , Derivação Gástrica/métodos , Obesidade/cirurgia , Medicina Baseada em Evidências/métodos , Gastrectomia/estatística & dados numéricos , Derivação Gástrica/estatística & dados numéricos , Humanos , Laparoscopia , Metanálise como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos
8.
Forensic Sci Int Genet ; 44: 102200, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31760353

RESUMO

We describe an ancestry-informative autosomal SNP multiplex designed to be a small-scale, flexible panel that can complement uniparental markers in assessing the American variability (i.e. pre-Colombian) found in contemporary indigenous American populations. This study centered on choosing SNPs with the specific characteristics of: 1) extreme allele frequency differences between indigenous Americans and the African, European and East Asian population groups that contribute to present-day population variation in the Americas; 2) high informativeness-for-assignment In values; and 3) well-spaced genomic distribution and chromosomal separation from existing small-scale forensic ancestry marker sets. The resulting capillary electrophoresis SNaPshot single base extension test was named: PIMA (Population Informative Multiplex for the Americas), comprising 26 autosomal SNPs, a single X-chromosome SNP plus the amelogenin sex marker adapted for SNaPshot. PIMA complements the established 34plex forensic ancestry panel to provide a powerful and simple tool for the analysis of American populations, including those with admixed histories, commonly encountered in America. Comparing the results obtained with the combined marker panels of PIMA and 34plex to SNP data from a much larger ancestry panel allowed us to gauge their relative efficiency. PIMA+34plex gives equivalent power to the 314-SNP 'LACE' genomic ancestry control panel, while requiring a much smaller genotyping effort. The ancestry profiles and genetic structure of 22 populations spread across the American continent were estimated using PIMA+34plex data, and those estimates were contrasted with information provided by uniparental markers (mtDNA and Y-chromosome loci) for a small set of admixed individuals from Venezuela. Our results indicate that an American genetic component is efficiently detected in contemporary American populations using a small set of ancestry informative SNPs, and these co-ancestry estimates are consistent with the known history and demography of the Americas. The small scale and high population differentiation power of PIMA, particularly when combined with 34plex, provides a practical and powerful tool for genetic studies of American populations as well as forensic DNA analyses.


Assuntos
Etnicidade/genética , Genética Populacional , Polimorfismo de Nucleotídeo Único , Grupos Raciais/genética , Amelogenina/genética , América , Cromossomos Humanos Y , DNA Mitocondrial , Eletroforese Capilar , Frequência do Gene , Marcadores Genéticos , Genótipo , Humanos , Reação em Cadeia da Polimerase Multiplex
9.
Phys Rev E ; 100(2-1): 023002, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31574657

RESUMO

This study investigates the tearing of a thin notched sheet when two points on the sheet are pulled apart. The concepts that determine the crack trajectory are reviewed in the general anisotropic case, in which the energy of the fracture depends on the fracture direction. When observed as a flat sheet a purely geometric "tearing vector" is defined through the location of the crack tip and the pulling points. Both Griffiths's criterion and the maximum energy release rate criterion (MERR) predict a fracture path that is parallel to the tearing vector in the isotropic case. However, for the anisotropic case, the application of the MERR leads to a crack path that deviates from the tearing vector, following a propagation direction that tends to minimize the fracture energy. In the case of strong anisotropy, it is more difficult to obtain an analytical prediction of the tearing trajectory. Thus, simple geometrical arguments are provided to give a derivation of a differential equation accounting for crack trajectory, according to the natural coordinates of the pulling, and in the case that the anisotropy is sufficiently weak. The solution derived from this analysis is in good agreement with previous experimental observations.

10.
J Food Prot ; 82(11): 1896-1900, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31622164

RESUMO

Chicken carcass frames are used to obtain mechanically separated chicken (MSC) for use in other further processed food products. Previous foodborne disease outbreaks involving Salmonella-contaminated MSC have demonstrated the potential for the human pathogen to be transmitted to consumers via MSC. The current study evaluated the efficacy of multiple treatments applied to the surfaces of chicken carcass frames to reduce microbial loads on noninoculated frames and frames inoculated with a cocktail of Salmonella enterica serovar Enteritidis and Salmonella enterica serovar Typhimurium. Inoculated or noninoculated frames were left untreated (control) or were subjected to treatment using a prototype sanitization apparatus. Treatments consisted of (i) a sterile water rinse, (ii) a water rinse followed by 5 s of UV-C light application, or (iii) an advanced oxidation process (AOP) combining 5 or 7% (v/v) hydrogen peroxide (H2O2) with UV-C light. Treatment with 7% H2O2 and UV-C light reduced numbers of aerobic bacteria by up to 1.5 log CFU per frame (P < 0.05); reductions in aerobic bacteria subjected to other treatments did not statistically differ from one another (initial mean load on nontreated frames: 3.6 ± 0.1 log CFU per frame). Salmonella numbers (mean load on inoculated, nontreated control was 5.6 ± 0.2 log CFU per frame) were maximally reduced by AOP application in comparison with other treatments. No difference in Salmonella reductions obtained by 5% H2O2 (1.1 log CFU per frame) was detected compared with that obtained following 7% H2O2 use (1.0 log CFU per frame). The AOP treatment for sanitization of chicken carcass frames reduces microbial contamination on chicken carcass frames that are subsequently used for manufacture of MSC.


Assuntos
Galinhas , Microbiologia de Alimentos , Peróxido de Hidrogênio , Raios Ultravioleta , Animais , Contagem de Colônia Microbiana , Microbiologia de Alimentos/métodos , Humanos , Peróxido de Hidrogênio/farmacologia , Salmonella enteritidis/efeitos dos fármacos , Salmonella enteritidis/efeitos da radiação , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/efeitos da radiação
13.
J Appl Res Intellect Disabil ; 31 Suppl 1: 97-109, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28833967

RESUMO

BACKGROUND: There is a lack of health promotion programming designed to change the physical activity environment of the group home setting. The Menu-Choice programme assists staff in creating physical activity goals alongside residents with intellectual disabilities and provides strategies to incorporate activity into the group home schedule. The purpose of this study was to complete a process evaluation of Menu-Choice utilizing qualitative methods. METHODS: Twelve participants, who completed a 10-week pilot intervention (n = 7 staff, mean age 42; n = 5 residents, mean age 52), participated in face-to-face interviews. Participants represented five group home sites involved in the intervention. RESULTS: Meta-themes included: (i) Programme training, (ii) Programme implementation, (iii) Programme physical activity, (iv) Programme barriers, (v) Programme facilitators and (vi) Programme feedback. CONCLUSIONS: Changes in programme training and simplified programme materials are needed to accommodate identified barriers for implementation. The importance of obtaining increased agency support and policy change is highlighted.


Assuntos
Exercício Físico , Lares para Grupos , Promoção da Saúde/métodos , Deficiência Intelectual/reabilitação , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Adulto Jovem
14.
Vet Pathol ; 54(1): 171-177, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27281016

RESUMO

The olive ridley sea turtle ( Lepidochelys olivacea), considered the most abundant sea turtle species, is listed as vulnerable on the International Union for Conservation of Nature Red List. The most important nesting areas are located in the Eastern Pacific, and congenital malformations have been previously reported in this species. The present study was conducted in a single population at El Verde beach, one of the most important nesting beaches for the species in the northwestern Mexican Pacific. The study was based on embryos that had been incubated in a controlled environment. Schistosomus reflexus syndrome (SRS) was observed in 124 of 20 257 olive ridley embryos (0.6%), comprising 124 of 400 (31%) cases of congenital malformations over a 7-month period. Affected embryos had malformations of the carapace, bridge, or plastron, resulting in exposure of the abdominal or thoracic viscera, as well as spinal malformation and abnormal positioning of limbs adjacent to the head with subsequent ankylosis. SRS phenotypes (although lethal) varied from mild to severe, although most cases were severe. SRS was mostly associated with congenital malformations in the neck (short neck, 80%), tail (anury, 38%), and flippers (different types of dysmelias, 53%). In most cases of severe SRS, ankyloses were present. Documenting these findings could be important to identify the cause of the developmental defects, and identification of the cause of the defects may be of significance to the population and to our efforts to manage this and other populations at risk.


Assuntos
Tartarugas/anormalidades , Anormalidades Múltiplas/patologia , Anormalidades Múltiplas/veterinária , Animais , Feminino , México , Oceano Pacífico , Síndrome , Tartarugas/embriologia
15.
Transplant Proc ; 48(2): 578-82, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27110007

RESUMO

BACKGROUND: The function of renal transplant grafts can be modified by many factors. In one study of graft weight/weight of the recipient, it was concluded to avoid renal transplantation in patients with kidneys with a low ratio between the graft and recipient weight (<2.5 g/kg). OBJECTIVE: The objective of this study was to describe the association between renal allograft weight and renal function 1 month after renal transplantation in the Mexican population. MATERIAL AND METHODS: We studied patients who underwent transplantation from living or cadaveric donors with 1 month of follow-up with a functioning graft. An observational, retrospective, analytic study from January 1, 2014 to November 1, 2014 was conducted. Graft weight, donor weight, recipient weight, age, donor gender, recipient creatinine, and renal function were recorded. RESULTS: A total of 88 patients were included: 35 women (39.8%) and 53 men (60.2%). Sixty (68%) received kidneys from living donors and 28 (31.8%) from deceased donors. Mean recipient body mass index (BMI) was 24.7 (±2.6). Mean graft weight was 152 g (±33.9). Creatinine at 1 month post-transplantation was 1.6 mg/dL (±2.0). Using a linear regression model cold ischemia time was related to serum creatinine at 1 month post-transplantation (P = .020). Using multivariate analysis, significance was observed with respect to these indexes and recipient renal function. Recipient gender also was related and showed statistical significance (P = .015). CONCLUSIONS: Renal graft function depends on many factors including the amount of functional renal mass and nephrons required according to the recipient's weight. The donor kidney weigt (DKW) / receptor body weigt (RBW) index should be considered as selection criteria of donors.


Assuntos
Índice de Massa Corporal , Peso Corporal , Taxa de Filtração Glomerular/fisiologia , Transplante de Rim , Rim/fisiopatologia , Doadores Vivos , Adulto , Aloenxertos , Feminino , Humanos , Masculino , Tamanho do Órgão , Estudos Retrospectivos
16.
Med Hypotheses ; 88: 38-45, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26880635

RESUMO

The progressive loss of neurons and inflammation characterizes neurodegenerative diseases. Although the etiology, progression and outcome of different neurodegenerative diseases are varied, they share chronic inflammation maintained largely by central nervous system (CNS)-derived antigens recognized by T cells. Inflammation can be beneficial by recruiting immune cells to kill pathogens or to clear cell debris resulting from the primary insult. However, chronic inflammation exacerbates and perpetuates tissue damage. An increasing number of therapies that attempt to modulate neuroinflammation have been developed. However, so far none has succeeded in decreasing the secondary damage associated with chronic inflammation. A potential strategy to modulate the immune system is related to the induction of tolerance to CNS antigens. In this line, it is our hypothesis that this could be accomplished by using anterior chamber associated immune deviation (ACAID) as a strategy. Thus, we review current knowledge regarding some neurodegenerative diseases and the associated immune response that causes inflammation. In addition, we discuss further our hypothesis of the possible usefulness of ACAID as a therapeutic strategy to ameliorate damage to the CNS.


Assuntos
Câmara Anterior/imunologia , Inflamação , Doenças Neurodegenerativas/imunologia , Doença de Alzheimer/imunologia , Esclerose Lateral Amiotrófica/imunologia , Antígenos/imunologia , Sistema Nervoso Central/imunologia , Doenças do Sistema Nervoso Central/imunologia , Olho/imunologia , Humanos , Sistema Imunitário , Tolerância Imunológica , Esclerose Múltipla/imunologia , Doenças Neurodegenerativas/terapia , Neurônios/metabolismo , Baço/imunologia , Linfócitos T Reguladores/imunologia , Timo/imunologia
17.
Cuad. med. forense ; 21(3/4): 152-161, jul.-dic. 2015.
Artigo em Espanhol | IBECS | ID: ibc-154844

RESUMO

La configuración del Registro Civil como organismo administrativo que introduce la Ley 20/2011, de 21 de julio, del Registro Civil; la omisión de la mención al médico forense en alguno de su preceptos relativos a la inscripción de la defunción, siendo sustituida por la más genérica de facultativo; la nueva ordenación de las funciones del colectivo forense por Ley Orgánica 7/2015, de 21 julio, de reforma de la Ley Orgánica del Poder judicial, eliminando de entre ellas la asistencia técnica a las Oficinas del Registro civil; y por último la modificación de parte del articulado de la Ley del Registro Civil relativo a la inscripción de fallecimiento por Ley 15/2015, de 2 de julio, de Jurisdicción voluntaria, y por Ley 19/2015, de 13 de julio, de medidas de reforma administrativa en el ámbito de la Administración de Justicia y del Registro Civil, justifican a mi entender el tratamiento registral del fallecimiento, realidad jurídica tan vinculada al colectivo forense (AU)


The new role of the Civil Registry as an administrative body introduced by the Law 20/2011, July 21; the omission to mention the forensic surgeon in any of its provisions relating to the registration of the decease being replaced by physician; the new organization of the forensic surgeon body by the Organic Law 7/2015, July 21, to reform the Organic Law of Judiciary Power, eliminating the technical assistance to Civil Registry offices; finally, the modification of the articles related to the entry of death by the Law 15/2015, July 2, of voluntary jurisdiction, and by the Law 19/2015, July 13, of administrative reform measures in the field of the Administration of Justice and the Civil Registry, justify the study of the death registration legal reality as related to the forensic surgeon body (AU)


Assuntos
Humanos , Masculino , Feminino , Atestado de Óbito/legislação & jurisprudência , Registros/legislação & jurisprudência , Registros/normas , Registro Civil/normas , Registro Civil/estatística & dados numéricos , Medicina Legal/legislação & jurisprudência , Morte , Medicina Legal/organização & administração , Medicina Legal/normas
18.
J Phys Chem Lett ; 6(22): 4646-52, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26551347

RESUMO

The influence of spin multiplicity on the melting of the Na55(+) cluster has been investigated by means of all-electron Kohn-Sham Born-Oppenheimer molecular dynamics simulations. On the basis of the quantitative agreement between the experimental and theoretical melting temperature and latent heat a detailed analysis of the cluster dynamics was performed. This analysis showed a significant structure deformation of the cluster that is inconsistent with the geometrical shell closing concept. In subsequent structure optimizations a high-spin ground state in perfect icosahedral symmetry was found for the Na55(+) cluster. The Born-Oppenheimer molecular dynamics of this high-spin Na55(+) cluster indicates a particular thermal stability of the icosahedral cluster structure. A new electronic mechanism, named subshell closing, is suggested as the origin for this enhanced thermal stability of the icosahedral cluster structure. This mechanism is a natural extension of the common jellium model. By its nature, the subshell closing mechanism is general for finite systems and expected to be found in many other clusters for which the jellium model is applicable.

20.
Nanoscale ; 7(18): 8566-73, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-25898392

RESUMO

Stable, alkyl-terminated, light-emitting silicon nanoparticles have been synthesized in a continuous process by laser pyrolysis of a liquid trialkyl-silane precursor selected as a safer alternative to gas silane (SiH4). Stabilization was achieved by in situ reaction using a liquid collection system instead of the usual solid state filtration. The alkene contained in the collection liquid (1-dodecene) reacted with the newly formed silicon nanoparticles in an unusual room-temperature hydrosilylation process. It was achieved by the presence of fluoride species, also produced during laser pyrolysis from the decomposition of sulfur hexafluoride (SF6) selected as a laser sensitizer. This process directly rendered alkyl-passivated silicon nanoparticles with consistent morphology and size (<3 nm), avoiding the use of costly post-synthetic treatments.

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