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1.
Glob Chang Biol ; 29(9): 2536-2556, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36802091

RESUMEN

The terrestrial water cycle links the soil and atmosphere moisture reservoirs through four fluxes: precipitation, evaporation, runoff, and atmospheric moisture convergence (net import of water vapor to balance runoff). Each of these processes is essential for sustaining human and ecosystem well-being. Predicting how the water cycle responds to changes in vegetation cover remains a challenge. Recently, changes in plant transpiration across the Amazon basin were shown to be associated disproportionately with changes in rainfall, suggesting that even small declines in transpiration (e.g., from deforestation) would lead to much larger declines in rainfall. Here, constraining these findings by the law of mass conservation, we show that in a sufficiently wet atmosphere, forest transpiration can control atmospheric moisture convergence such that increased transpiration enhances atmospheric moisture import and results in water yield. Conversely, in a sufficiently dry atmosphere increased transpiration reduces atmospheric moisture convergence and water yield. This previously unrecognized dichotomy can explain the otherwise mixed observations of how water yield responds to re-greening, as we illustrate with examples from China's Loess Plateau. Our analysis indicates that any additional precipitation recycling due to additional vegetation increases precipitation but decreases local water yield and steady-state runoff. Therefore, in the drier regions/periods and early stages of ecological restoration, the role of vegetation can be confined to precipitation recycling, while once a wetter stage is achieved, additional vegetation enhances atmospheric moisture convergence and water yield. Recent analyses indicate that the latter regime dominates the global response of the terrestrial water cycle to re-greening. Evaluating the transition between regimes, and recognizing the potential of vegetation for enhancing moisture convergence, are crucial for characterizing the consequences of deforestation as well as for motivating and guiding ecological restoration.


Asunto(s)
Ecosistema , Bosques , Humanos , Suelo , Atmósfera , Transpiración de Plantas
2.
Obes Surg ; 32(2): 256-265, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34973123

RESUMEN

BACKGROUND: Efficacy and safety of OAGB/MGB (one anastomosis/mini gastric bypass) have been well documented both as primary and as revisional procedures. However, even after OAGB/MGB, revisional surgery is unavoidable in patients with surgical complications or insufficient weight loss. METHODS: A questionnaire asking for the total number and demographics of primary and revisional OAGB/MGBs performed between January 2006 and July 2020 was e-mailed to all S.I.C. OB centres of excellence (annual caseload > 100; 5-year follow-up > 50%). Each bariatric centre was asked to provide gender, age, preoperative body mass index (BMI) and obesity-related comorbidities, previous history of abdominal or bariatric surgery, indication for surgical revision of OAGB/MGB, type of revisional procedure, pre- and post-revisional BMI, peri- and post-operative complications, last follow-up (FU). RESULTS: Twenty-three bariatric centres (54.8%) responded to our survey reporting a total number of 8676 primary OAGB/MGBS and a follow-up of 62.42 ± 52.22 months. A total of 181 (2.08%) patients underwent revisional surgery: 82 (0.94%) were suffering from intractable DGER (duodeno-gastric-esophageal reflux), 42 (0.48%) were reoperated for weight regain, 16 (0.18%) had excessive weight loss and malnutrition, 12 (0.13%) had a marginal ulcer perforation, 10 (0.11%) had a gastro-gastric fistula, 20 (0.23%) had other causes of revision. Roux-en-Y gastric bypass (RYGB) was the most performed revisional procedure (109; 54%), followed by bilio-pancreatic limb elongation (19; 9.4%) and normal anatomy restoration (19; 9.4%). CONCLUSIONS: Our findings demonstrate that there is acceptable revisional rate after OAGB/MGB and conversion to RYGB represents the most frequent choice.


Asunto(s)
Derivación Gástrica , Fístula Gástrica , Obesidad Mórbida , Derivación Gástrica/efectos adversos , Derivación Gástrica/métodos , Fístula Gástrica/cirugía , Humanos , Obesidad Mórbida/cirugía , Reoperación/métodos , Estudios Retrospectivos , Encuestas y Cuestionarios , Pérdida de Peso
3.
Nutrients ; 15(1)2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36615848

RESUMEN

Development of the Italian clinical practice guidelines on bariatric and metabolic surgery, as well as design and methodological aspects. BACKGROUND: Obesity and its complications are a growing problem in many countries. Italian Society of Bariatric and Metabolic Surgery for Obesity (Società Italiana di Chirurgia dell'Obesità e delle Malattie Metaboliche-SICOB) developed the first Italian guidelines for the treatment of obesity. METHODS: The creation of SICOB Guidelines is based on an extended work made by a panel of 24 members and a coordinator. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) methodology has been used to decide the aims, reference population, and target health professionals. Clinical questions have been created using the PICO (Patient, Intervention, Comparison, Outcome) conceptual framework. The definition of questions used the two-step web-based Delphi method, made by repeated rounds of questionnaires and a consensus opinion from the panel. RESULTS: The panel proposed 37 questions. A consensus was immediately reached for 33 (89.2%), with 31 approved, two rejected and three which did not reach an immediate consensus. The further discussion allowed a consensus with one approved and two rejected. CONCLUSIONS: The areas covered by the clinical questions included indications of metabolic/bariatric surgery, types of surgery, and surgical management. The choice of a surgical or a non-surgical approach has been debated for the determination of the therapeutic strategy and the correct indications.


Asunto(s)
Cirugía Bariátrica , Humanos , Cirugía Bariátrica/métodos , Obesidad/cirugía , Guías de Práctica Clínica como Asunto
5.
Ecol Modell ; 359: 285-292, 2017 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-28900312

RESUMEN

Understanding overfishing and regulating fishing quotas is a major global challenge for the 21st Century both in terms of providing food for humankind and to preserve the oceans' ecosystems. However, fishing is a complex economic activity, affected not just by overfishing but also by such factors as pollution, technology, financial factors and more. For this reason, it is often difficult to state with complete certainty that overfishing is the cause of the decline of a fishery. In this study, we developed a simple dynamic model specifically designed to isolate and to study the role of depletion on production. The model is based on the well-known Lotka-Volterra model, or Prey-Predator mechanism, assuming that the fish stock and the fishing industry are coupled variables that dynamically affect each other. In the model, the fishing industry acts as the "predator" and the fish stock as the "prey". If the model can fit historical data, in particular relative to the productive decline of specific fisheries, then we have a strong indication that the decline of the fish stock is driving the decline of the fishery production. The model doesn't pretend to be a general description of the fishing industry in all its varied forms; however, the data reported here show that the model can describe several historical cases of fisheries whose production decreased and collapsed, indicating that the overexploitation of the fish stocks is an important factor in the decline of fisheries.

6.
Phys Chem Chem Phys ; 14(15): 5045-51, 2012 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-22378187

RESUMEN

Interfaces and surfaces are the regions where important events happen: catalysis, molecular recognition, charge transfer, polymerization, and many other critical processes take place at the boundary between one medium and another. In this article we discuss the interface (liquid/air) properties of ionic liquids (ILs) containing dissolved metal ions with the aim to show the possibility to use metal salts to transform ILs and their surfaces into engineered liquid supports to apply in material sciences, separation procedures or to use as optical devices.


Asunto(s)
Líquidos Iónicos/química , Metales/química , Imidazoles/química , Iones/química , Propiedades de Superficie
7.
Microsc Res Tech ; 74(10): 931-5, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21484939

RESUMEN

Combustion processes commonly create fine and ultrafine particles whose effects are often harmful to human health. The present study is aimed at providing more data in this field by testing the capability of environmental electron scanning microscopy of detecting and analyzing such particles. For this purpose, we examined a range of samples taken from everyday food items collected in Tuscany. The results showed that, within the examined samples, inorganic particles can be observed in the nano- and micrometer range. These particles are attributable mostly to natural processes and, in part, to food processing. Little evidence is found for particles whose origin could be attributed to industrial combustion processes, such as waste incineration.


Asunto(s)
Contaminación de Alimentos/análisis , Material Particulado/química , Contaminantes Atmosféricos/química , Contaminación del Aire , Análisis de los Alimentos , Contaminación de Alimentos/estadística & datos numéricos , Microscopía Electrónica de Rastreo , Tamaño de la Partícula
8.
Rapid Commun Mass Spectrom ; 23(1): 147-50, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19061208

RESUMEN

Knudsen high-temperature mass spectrometry was used to study the process of sublimation of a solid electrolyte (AgI)(0.5-)(AgPO(3))(0.5). Monoatomic iodine ions were found to be the dominant species in the electron ionization mass spectra below 600 degrees C. With an increase in temperature, the relative content of phosphorus oxide ions, mainly [PO](+) and [P(4)O(10)](+), increased. Under further heating, we observed silver iodide and iodine dimer ions together with phosphorus dimer and tetramer ions and clusters [IPO(2)](+), [IP(2)](+), [I(3)P](+). Using the experimental logarithmic dependencies of ion signal intensities versus the reciprocal absolute temperature of the effusion cell, the apparent sublimation enthalpies Delta(s)H of the ions giving the most intense signals were estimated.

9.
Hepatogastroenterology ; 54(80): 2328-32, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18265658

RESUMEN

BACKGROUND/AIMS: Laparoscopic cholecystectomy is characterized by a higher incidence of iatrogenic biliary lesions. The Authors evaluate the role of hepaticojejunostomy in the treatment of iatrogenic biliary lesions following laparoscopic cholecystectomy in 51 patients observed in the Campania region, Italy from 1991 to 2003. METHODOLOGY: The Authors report the data of a retrospective multicentric study of 51 patients -39 women (76.47%), 12 men (13.53%)-reoperated on for major biliary lesions following laparoscopic cholecystectomy. Hepaticojejunostomy in 20 cases (39.21%) and T-Tube plasty in 20 cases (39.21%) were performed. RESULTS: The mean follow-up was 25.01 months. The mean hospital stay was 25.7 days. 1/51 patients (1.9%) died from intraoperative incontrollable hemorrhage while cumulative postoperative mortality was 9.8% (5/51 patients). Therapeutic success rate of hepaticojejunostomy was 70% with a T-Tube plasty success rate of 65%. 9/51 patients (17.64%) were reoperated while in 4/51 (7.84%) a biliary stent was positioned. In 1/51 patients (1.9%) a biliary cirrhosis and in 3/51 (5.7%) a bioumoral cholestasis was observed. CONCLUSIONS: Laparoscopic cholecystectomy causes a higher incidence of iatrogenic biliary lesions. Hepaticojejunostomy gives better long-term results and lower morbidity compared to T-Tube plasty. Management of septic complications in patients with iatrogenic biliary lesions represents the first therapeutic step.


Asunto(s)
Conductos Biliares/lesiones , Colecistectomía Laparoscópica/efectos adversos , Complicaciones Intraoperatorias/cirugía , Yeyunostomía , Adolescente , Adulto , Anciano , Femenino , Encuestas de Atención de la Salud , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
10.
Chir Ital ; 57(4): 417-24, 2005.
Artículo en Italiano | MEDLINE | ID: mdl-16060179

RESUMEN

An higher incidence rate of iatrogenic bile duct injuries is reported in cholecystectomy performed with the laparoscopy than with the laparotomy approach. The aim of this study was to provide a multicentre report on surgical treatment and the outcome of biliary complications during and following laparoscopic cholecystectomy. A questionnaire was mailed to all surgeons with experience in laparoscopic cholecystectomy in the Campania region. Data were collected from January 1991 to December 2003. Each patient was requested to indicate age, gender, associated diseases, site and type of lesion, surgical experience, diagnosis, treatment and complications. Twenty-six surgeons answered the questionnaire. Fifty-one patients (36 F/15 M; mean age: 42.5 +/- 11.9, range 13-91 years) with bile duct injuries following laparoscopic cholecystectomy were reported. The most frequent lesions were main bile duct partial or total transection. The intraoperative mortality rate was 1/51 (1.9%) due to a complex biliary and vascular injury. The postoperative mortality rate of revision surgery was 5/50 (10%). T-tube positioning (n = 20) and Roux-en-Y hepato-jejunostomy (n = 20) were the procedures most frequently performed. The complication rate in patients treated with the T-tube was significantly higher than in those treated with hepatico-jejunostomy. Surgical treatment of biliary injuries following laparoscopic cholecystectomy was characterized by unusually high mortality and morbidity for a non-neoplastic disease. Roux-en-Y hepato-jejunostomy remains the procedure of choice for these injuries.


Asunto(s)
Conductos Biliares/lesiones , Conductos Biliares/cirugía , Colecistectomía Laparoscópica/efectos adversos , Enfermedad Iatrogénica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anastomosis en-Y de Roux , Colecistectomía Laparoscópica/mortalidad , Drenaje , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reoperación , Estudios Retrospectivos , Encuestas y Cuestionarios , Análisis de Supervivencia
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