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1.
Anaesthesia ; 79(3): 309-317, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38205529

RESUMO

Global warming is a major public health concern. Volatile anaesthetics are greenhouse gases that increase the carbon footprint of healthcare. Modelling studies indicate that total intravenous anaesthesia is less carbon intensive than volatile anaesthesia, with equivalent quality of care. In this observational study, we aimed to apply the findings of previous modelling studies to compare the carbon footprint per general anaesthetic of an exclusive TIVA strategy vs. a mixed TIVA-volatile strategy. This comparative retrospective study was conducted over 2 years in two French hospitals, one using total intravenous anaesthesia only and one using a mixed strategy including both intravenous and inhalation anaesthetic techniques. Based on pharmacy procurement records, the quantity of anaesthetic sedative drugs was converted to carbon dioxide equivalents. The primary outcome was the difference in carbon footprint of hypnotic drugs per intervention between the two strategies. From 1 January 2021 to 31 December 2022, 25,137 patients received general anaesthesia in the hospital using the total intravenous anaesthesia strategy and 22,020 in the hospital using the mixed strategy. The carbon dioxide equivalent footprint of hypnotic drugs per intervention in the hospital using the total intravenous anaesthesia strategy was 20 times lower than in the hospital using the mixed strategy (emissions of 2.42 kg vs. 48.85 kg carbon dioxide equivalent per intervention, respectively). The total intravenous anaesthesia strategy significantly reduces the carbon footprint of hypnotic drugs in general anaesthesia in adult patients compared with a mixed strategy. Further research is warranted to assess the risk-benefit ratio of the widespread adoption of total intravenous anaesthesia.


Assuntos
Anestésicos Gerais , Anestésicos Inalatórios , Propofol , Adulto , Humanos , Propofol/efeitos adversos , Anestesia Intravenosa/métodos , Pegada de Carbono , Dióxido de Carbono , Estudos Retrospectivos , Anestesia Geral , Hipnóticos e Sedativos
2.
BMC Vet Res ; 18(1): 163, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35509073

RESUMO

BACKGROUND: Nowadays, more people are treating dogs as family members. This reflects their increased attention towards their nutrition, with renewed interest for non-conventional diets such as Biologically Appropriate Raw Food/ Bones and Raw Food in United States (BARF) or homemade. In previous studies, owners feeding their dog non-conventional diets reported lower levels of trust in veterinary advice. The aim of the study was to identify differences in lifestyle between owners feeding dogs non-conventional diets and those feeding conventional diets (i.e., dry/wet pet food) to give further insight for improving communication between veterinarians and owners. RESULTS: A total of 426 surveys were usable. Fifteen percent of the participants lived in the metropole of Paris and had more than one dog (mean 1.72 dogs). Thirty-eight percent of the survey respondents stated that their dogs were fed exclusively with non-conventional diets, while 55% declared using conventional diets alone (not considering treats). The study canine population was for the most part neutered (63%) and purebred (68%). Amongst owners feeding conventional diets exclusively, 47% determined how much food to feed by consulting the feeding guidelines on the packaging, and only 28% said that the amount of food was prescribed by their veterinarian or veterinary nurse. Out of the participants feeding non-conventional diets, 65% declared that the information for formulating the recipes was gathered on the internet or in non-veterinary books. When compared with owners feeding exclusively conventional diets, those feeding non-conventional diets were living more frequently outside the metropole of Paris, had fewer children (0.23 ± 0.57 vs 0.37 ± 0.78; p = 0.03) and had more frequently other animals. They also dewormed less often their pets, walked their dog more each day (91 vs 78%; p < 0.001) and without leash for more than 6 h per week (46 vs 31%; p = 0.003). CONCLUSIONS: This survey described differences in the habits of owners feeding dogs non-conventional diets in comparison with those feeding conventional diets. Data suggest that owners using non-conventional diets may be more attentive to the ethological needs of their dog which could be a starting point for practitioners for achieving better client-veterinarian communication.


Assuntos
Ração Animal , Médicos Veterinários , Ração Animal/análise , Animais , Dieta/veterinária , Cães , França , Humanos , Animais de Estimação , Inquéritos e Questionários , Estados Unidos
3.
Clin Exp Dermatol ; 47(4): 765-767, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34856003

RESUMO

An 83-year-old woman was referred to the Dermatology department with a papular eruption on her left arm, occurring below the scar site of a malignant melanoma in situ, which had been excised 6 months previously. On physical examination, multiple, tender, violaceous papules and nodules inferior to the scar were noted, with central pustules in some of the lesions.


Assuntos
Melanoma , Neoplasias Cutâneas , Idoso de 80 Anos ou mais , Feminino , Granuloma , Humanos , Neoplasias Cutâneas/patologia , Supuração , Vacúolos/patologia
4.
J Insect Sci ; 22(3)2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35640027

RESUMO

The augmentorium is a cost-effective screened enclosure designed to receive fruits infested with insect pests, retain the pests inside but let their natural enemies escape to enhance biological control of pest populations. Screen selection is critical to ensure that an augmentorium is effective for a particular system. Here we tested five types of screens with a mini-augmentorium design and measured the escape of four insect species under laboratory conditions: the pests olive fruit fly Bactocera oleae (Rossi) (Diptera: Tephritidae) and Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), and the parasitoids Psyttalia lounsburyi (Silvestri) (Hymenoptera: Braconidae) and Psyttalia ponerophaga (Silvestri) (Hymenoptera: Braconidae). The sex ratio of insects that escaped the screens was compared to the sex ratio of insects that could not escape. Results showed that one screen type ('crystal mesh') was the best for the purpose of designing a functional augmentorium: it retained 90% of B. oleae adults and 100% of C. capitata adults while letting 72% of Psyttalia lounsburyi adults and 94% of P. ponerophaga adults escape. The other screen types tested were suboptimal, either because they let too many flies freely escape or because they retained too many parasitoids. Sex ratio was almost always similar for insects that managed to escape the screens and insects that were retained, except for P. ponerophaga and the screen type 'light mesh'. These results are promising for the development of a functional augmentorium against the olive fruit fly and further implementation against Mediterranean fruit fly.


Assuntos
Ceratitis capitata , Himenópteros , Olea , Controle Biológico de Vetores , Tephritidae , Animais , Drosophila
5.
Rev Neurol (Paris) ; 178(6): 616-623, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34872746

RESUMO

BACKGROUND: Growing numbers of indications for intravenous immunoglobulins (IVIg) in recent years has resulted in an increase in the consumption of these products. A lack of raw material has led to IVIg shortage. The objective of this work was to evaluate the impact of this situation on patient care in one French referral centre considering practice modifications and clinical impact. METHODS: All patients treated with IVIg for chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy and myasthenia gravis from October 2017 to October 2018 were included. RESULTS: Out of 142 patients, 111 (78%) had a modification of their IVIg treatment. We noted that 75 (68%) patients had a delay in IVIg treatment, 41 (37%) patients had a decrease in IVIg doses and 31 (28%) experienced IVIg treatment interruption. Thirty percent of patients for whom IVIg treatment was discontinued were switched to other treatments mainly plasma exchange (16%) or corticosteroids (13%). Switches to plasma exchange or corticosteroids were carried out in order to save immunoglobulins for patients who had no other alternatives. Fifty-eight (52%) patients presented a deterioration of their clinical score after IVIg treatment changes including 31 (28%) patients who had a moderate or a clinically significant deterioration. Concerning practice modifications, we noted a substantial though not significant decrease in median IVIg dose for myasthenia gravis and a significant increase in the delay between IVIg courses for chronic inflammatory demyelinating polyneuropathy and multifocal motor neuropathy (P=0.011 and P=0.018 respectively). CONCLUSION: Our study showed a rather important number of changes in IVIg treatment related to IVIg shortage during the period considered. These changes had a negative impact on the clinical status of some patients.


Assuntos
Miastenia Gravis , Polineuropatias , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Corticosteroides/uso terapêutico , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Miastenia Gravis/tratamento farmacológico , Polineuropatias/tratamento farmacológico , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/tratamento farmacológico
6.
Clin Exp Dermatol ; 46(8): 1656-1658, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34505309

RESUMO

This case illustrates a presentation with dystrophic calcinosis cutis recalcitrant to several treatment modalities. Treatment with extracorporeal shockwave lithotripsy was initiated with near complete resolution of calcium deposits.


Assuntos
Calcinose/patologia , Calcinose/terapia , Litotripsia , Dermatopatias/patologia , Dermatopatias/terapia , Idoso , Feminino , Humanos , Resultado do Tratamento
7.
J Intellect Disabil Res ; 65(8): 795-800, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33880800

RESUMO

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is a common co-morbidity that affects up to 44% of children with Down syndrome (DS). There is a need for reliable, good quality research on the use of methylphenidate within this population. The objective of this study is to report our experience regarding the management of ADHD in these children using methylphenidate. METHODS: This study is a retrospective observation of 21 children with DS, followed at Jérôme Lejeune Institute between 2000 and 2018. The diagnosis of ADHD was made using the Diagnostic and Statistical Manual of Mental Disorders criteria. Efficacy was measured as response or non-response on two main symptoms: attention/concentration and hyperactivity/impulsivity. Safety was evaluated by the presence or absence of side effects. RESULTS: Sixteen out of the 21 children (76%) showed improvement with methylphenidate. The average age of treatment onset in responding children was 8 years and 10 months versus 6 years and 3 months in non-responders (P = 0.05). Average dose/weight was significantly different in responders and non-responders (0.82 vs. 0.54 mg/kg/day, respectively; P = 0.03). Twelve children out of 21 (57%) experienced side effects; only three experienced side effects severe enough to require treatment interruption. Most common side effects were loss of appetite and difficulties in falling asleep. CONCLUSION: Methylphenidate was effective and safe in treating ADHD in 76% of cases in children with DS, with few serious side effects to report. Early diagnosis of ADHD is important to improve the quality of life, learning, inclusion and socialisation of children with DS.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Estimulantes do Sistema Nervoso Central , Síndrome de Down , Metilfenidato , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Estimulantes do Sistema Nervoso Central/efeitos adversos , Criança , Síndrome de Down/complicações , Síndrome de Down/epidemiologia , Humanos , Metilfenidato/efeitos adversos , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento
8.
Langmuir ; 36(39): 11411-11421, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-32911931

RESUMO

We studied the dependence of solid deposit shape obtained by free drying of sessile drops on particle concentration and Derjaguin-Landau-Verwey-Overbeek (DLVO) particle/substrate interaction. In contrast to previous contributions using pH as a control parameter of interactions, we investigated an unprecedentedly wide range of concentrations and particle/substrate DLVO forces by modifying the nature of the substrate and particles as well as their size and surface chemistry, whereas long-distance repulsive interactions between particles were maintained for most of the drying time. Our main result is that the different shapes of deposits obtained by modifying the particle concentration are the same in the different regimes of concentration regardless of particle/substrate interaction in the studied range of DLVO forces and particle concentrations. The second result is that, contrary to expectations, the dominant morphology of dry patterns at low particle concentration always shows a dotlike pattern for all the studied systems.

9.
Gynecol Oncol ; 153(2): 223-229, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30765148

RESUMO

BACKGROUND: Intraperitoneal (IP) chemotherapy can improve outcomes for women with optimally cytoreduced epithelial ovarian cancer but toxicities are a concern. We conducted 2 phase 2 trials of an IV/IP regimen using carboplatin and paclitaxel without (Trial A) and with bevacizumab (Trial B). METHODS: Both trials consisted of carboplatin AUC 6 day 1, and paclitaxel 60 mg/m2 on days 1,8, 15 of a 21-day cycle; in Trial B, patients received IV bevacizumab 15 mg/kg every cycle starting cycle 2. Chemotherapy was administered IV for cycle 1 and then IP for all subsequent cycles. Primary objectives included safety and tolerability, pathologic CR rate (Trial A), and the rate of completion of IP cycles of therapy (Trial B). Progression-free (PFS), overall survival (OS), and pharmacokinetic analysis were secondary endpoints. RESULTS: 81 patients were treated on both trials (n = 40 and 41 in trials A and B, respectively). Median age for trials A and B was 59 (range, 36-76) and 55 (range, 19-69) years, respectively. 68% and 85% of patients, respectively for A and B, completed at least 4 cycles of treatment in both trials. Treatment with bevacizumab resulted in higher rates of grade 3 fatigue (37 versus 33%) and grade 3-4 diarrhea (22 versus 8%). Median PFS was 23.5 (95%CI 16.2-35.3) and 25 (95%CI 16.4-42.7) months, respectively; median OS was 68 (95%CI 49.5-NR) and 79.7 (95%CI 59.0-79.7) months, respectively for Trial A and B. CONCLUSIONS: Weekly administered IP carboplatin and IP paclitaxel is tolerable and safe with similar activity with and without concommittant bevacizumab in these 2 trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Epitelial do Ovário/terapia , Neoplasias Ovarianas/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab/administração & dosagem , Bevacizumab/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Carcinoma Epitelial do Ovário/mortalidade , Carcinoma Epitelial do Ovário/patologia , Quimioterapia Adjuvante/métodos , Procedimentos Cirúrgicos de Citorredução/métodos , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Infusões Parenterais , Pessoa de Meia-Idade , Ductos Paramesonéfricos/patologia , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Ovariectomia/métodos , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Intervalo Livre de Progressão , Adulto Jovem
10.
J Biomol NMR ; 72(1-2): 29-38, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30117038

RESUMO

Pseudocontact shifts (PCS) generated by lanthanide chelating tags yield valuable restraints for investigating protein structures, dynamics and interactions in solution. In this work, dysprosium-, thulium- and terbium-complexes of eight-fold methylated 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid tags [DOTA-M8-(4R4S)-SSPy] are presented that induce large pseudocontact shifts up to 5.5 ppm and adopt exclusively the square antiprismatic conformation. This is in contrast to our earlier findings on complexes of the stereoisomeric DOTA-M8-(8S)-SSPy, where significant amounts of the twisted square antiprismatic conformer for the Dy tag were observed. The Dy-, Tm-, Tb- and Lu-complexes of DOTA-M8-(4R4S)-SSPy were conjugated to ubiquitin S57C and selectively 15N leucine labeled human carbonic anhydrase II S50C, resulting in only one set of signals. Furthermore, we investigated the conformation of the thulium- and dysprosium-complexes in vacuo and with implicit water solvent using density functional theory calculations. The calculated energy differences between the two different conformations (7.0-50.5 kJ/mol) and experimental evidence from the corresponding ytterbium- and yttrium-complexes clearly suggest a SAP [Λ(δδδδ)] geometry for the complexes presented in this study. The lanthanide chelating tag studied in this work offer insights into the solution structure of proteins by inducing strong pseudocontact shifts, show different tensor properties compared to its predecessor, enables a convenient assignment procedure, is accessed by a more economic synthesis than its predecessor and constitutes a highly promising starting point for further developments of lanthanide chelating tags.


Assuntos
Quelantes/química , Elementos da Série dos Lantanídeos/química , Ressonância Magnética Nuclear Biomolecular/métodos , Coloração e Rotulagem/métodos , Anidrase Carbônica II/química , Compostos Heterocíclicos com 1 Anel , Humanos , Modelos Moleculares , Conformação Proteica , Ubiquitina/química , Água/química
11.
J Biomed Inform ; 84: 31-41, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29935347

RESUMO

BACKGROUND: Rapid advancements in biomedical research have accelerated the number of relevant electronic documents published online, ranging from scholarly articles to news, blogs, and user-generated social media content. Nevertheless, the vast amount of this information is poorly organized, making it difficult to navigate. Emerging technologies such as ontologies and knowledge bases (KBs) could help organize and track the information associated with biomedical research developments. A major challenge in the automatic construction of ontologies and KBs is the identification of words with its respective sense(s) from a free-text corpus. Word-sense induction (WSI) is a task to automatically induce the different senses of a target word in the different contexts. In the last two decades, there have been several efforts on WSI. However, few methods are effective in biomedicine and life sciences. METHODS: We developed a framework for biomedical entity sense induction using a mixture of natural language processing, supervised, and unsupervised learning methods with promising results. It is composed of three main steps: (1) a polysemy detection method to determine if a biomedical entity has many possible meanings; (2) a clustering quality index-based approach to predict the number of senses for the biomedical entity; and (3) a method to induce the concept(s) (i.e., senses) of the biomedical entity in a given context. RESULTS: To evaluate our framework, we used the well-known MSH WSD polysemic dataset that contains 203 annotated ambiguous biomedical entities, where each entity is linked to 2-5 concepts. Our polysemy detection method obtained an F-measure of 98%. Second, our approach for predicting the number of senses achieved an F-measure of 93%. Finally, we induced the concepts of the biomedical entities based on a clustering algorithm and then extracted the keywords of reach cluster to represent the concept. CONCLUSIONS: We have developed a framework for biomedical entity sense induction with promising results. Our study results can benefit a number of downstream applications, for example, help to resolve concept ambiguities when building Semantic Web KBs from biomedical text.


Assuntos
Pesquisa Biomédica , Infecções por HIV/diagnóstico , Informática Médica/métodos , Algoritmos , Inteligência Artificial , Teorema de Bayes , Análise por Conglomerados , Bases de Dados Factuais , Infecções por HIV/epidemiologia , Bases de Conhecimento , Idioma , Aprendizado de Máquina , Processamento de Linguagem Natural , Web Semântica , Semântica , Unified Medical Language System , Vocabulário Controlado
12.
Pharmazie ; 73(5): 251-259, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29724289

RESUMO

The observed increase in cancer led to a continuous rise in anticancer drug preparations in Hospital Centres. The quality and security of these preparations are essential to ensure the efficacy and to limit the risk of iatrogenic toxicity. Several methods have been described to secure the process of preparation (i.e. non-analytical methods for the control during the fabrication; analytical methods for the final product evaluation). These different methods have been presented in many studies, in particular in descriptive studies, but in practice, selecting a method is difficult and related to needs and hospital priorities. Therefore, we decided to conduct this present review focused on various existing methods allowing enhancement in security of anti-cancer drugs preparation process. A proactive hazard analysis method was applied, considering preparation and control steps, to discuss the choice of a method in terms of quality and security and to identify potential risks of failure. The results show that none method is perfect. Methods with the lowest criticality score are the robotization closely followed by Drugcam® in the case of re-labelling of all containers. According to these elements a University Hospital Centre could consider these risk indexesimplementing control methods.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/química , Composição de Medicamentos/métodos , Antineoplásicos/efeitos adversos , Técnicas de Química Analítica/métodos , Humanos , Medicina de Precisão/métodos , Avaliação de Processos em Cuidados de Saúde , Controle de Qualidade , Gestão de Riscos/métodos , Robótica , Gestão da Segurança/métodos
13.
Int Nurs Rev ; 65(3): 392-399, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29266302

RESUMO

AIM: To explore the primary healthcare needs and health service use of homeless men in inner Sydney. BACKGROUND: People experiencing homelessness have greater health needs than the general population and place high demands on tertiary care, which is expensive and may not be the optimum service for their needs. Accessible, approachable and affordable primary healthcare services could improve the health of homeless persons and potentially decrease costs to the healthcare system. METHODS: A multimethod design using a cross-sectional survey (n = 40) and administrative data (n = 2 707 daily summaries) collected from a nurse-led primary healthcare clinic for homeless men in Sydney. FINDINGS: Survey respondents were aged 27-76 years. Health problems reflected multimorbidity, with mental health issues present in almost all respondents. The majority had attended the clinic more than 20 times in the past year and said the services, treatments and referrals helped them avoid the emergency department. Administrative data indicated that medication administration was the most frequent service provided. Referrals to other health services doubled over the 7-year period. DISCUSSION: Multiple morbidities, particularly mental health issues, are associated with homelessness. A proactive approach by nurses including preventative services appeared to overcome barriers to health service use. CONCLUSION: This nurse-led primary healthcare clinic highlights the importance of providing services to homeless men with multiple comorbidities. Respect and trust in addition to easy access to health services appear to be important facilitators of health service use. IMPLICATIONS FOR NURSING, AND IMPLICATIONS FOR HEALTH POLICY: A greater number of primary health services that collaborate with specialist services, including nurse-led clinics, may facilitate health care for persons who are homeless, reducing the burden on acute services.


Assuntos
Política de Saúde , Pessoas Mal Alojadas , Avaliação das Necessidades , Padrões de Prática em Enfermagem/organização & administração , Atenção Primária à Saúde/organização & administração , Adulto , Idoso , Austrália , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Ann Pharm Fr ; 75(5): 385-397, 2017 Sep.
Artigo em Francês | MEDLINE | ID: mdl-28583318

RESUMO

OBJECTIVES: Type 2 diabetes is a major public health concern because of its prevalence, the severity of complications and the financial implications. Compliance and patient's autonomy in medications intake play key roles in the success of treatment. Pharmacists' interviews ensure an optimized and individual follow-up. Type 2 diabetes is not one of the targeted diseases to perform pharmacists' interviews on under Health Insurance. We thus judged useful to contribute to their development. METHODS: We applied a cross-disciplinary methodological process in order to define the specifications of the follow-up form useful to conduct the pharmacist's interview 1 by focusing on the identification of a non-compliance and its origins. A feasibility study was carried out in order to check its workability to the pharmacy practice. RESULTS: The follow-up form, associated with a pharmacist practical guide, includes 3 parts: (1) General informations, (2) Survey establishing patient's knowledge, (3) Summary including a level of knowledge assessment grid. Outcomes provide a long but appropriate-felt duration, few difficulties to conduct the interview and a proven usefulness in 90% of all cases that make the follow-up form suitable to the pharmacy practice. CONCLUSIONS: This tool could serve as a model for the pharmacist to conduct his future interviews for the type 2 diabetes patients, thus improving patient care, together with other health professionals.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Custos de Medicamentos , Autonomia Pessoal , Seguimentos , Humanos , Pacientes/psicologia , Assistência Farmacêutica , Farmácias , Farmacêuticos
15.
Soft Matter ; 12(40): 8367-8374, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27722657

RESUMO

Periodic precipitation processes in gels can result in impressive micro- and nanostructured patterns known as periodic precipitation (or Liesegang bands). Under certain conditions, the silver nitrate-chromium(vi) system exhibits the coexistence of two kinds of Liesegang bands with different frequencies. We now present that the two kinds of bands form independently on different time scales and the pH-dependent chromate(vi)-dichromate(vi) equilibrium controls the formation of the precipitates. We determined the spatial distribution and constitution of the particles in the bands using focused ion beam-scanning electron microscopy (FIB-SEM) and scanning transmission X-ray spectromicroscopy (STXM) measurements. This provided the necessary empirical input data to formulate a model for the pattern formation; a model that quantitatively reproduces the experimental observations. Understanding the pattern-forming process at the molecular level enables us to tailor the size and the shape of the bands, which, in turn, can lead to new functional architectures for a range of applications.

16.
Langmuir ; 31(5): 1828-34, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25586218

RESUMO

The synthesis of different sizes of nanoparticles and microparticles is important in designing nanostructured materials with various properties. Wet synthesis methods lack the flexibility to create various sizes of particles (particle libraries) using fixed conditions without the repetition of the steps in the method with a new set of parameters. Here, we report a synthesis method based on nucleation and particle growth in the wake of a moving chemical front in a gel matrix. The process yields well-separated regions (bands) filled with nearly monodisperse nanoparticles and microparticles, with the size of the particles varying from band to band in a predictable way. The origin of the effect is due to an interplay of a precipitation reaction of the reagents and their diffusion that is controlled in space and time by the moving chemical front. The method represents a new approach and a promising tool for the fast and competitive synthesis of various sizes of colloidal particles.


Assuntos
Microesferas , Microtecnologia/métodos , Nanopartículas/química , Nanotecnologia/métodos , Tamanho da Partícula , Difusão
18.
J Fish Biol ; 87(4): 1072-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26283180

RESUMO

A specimen of angular roughshark Oxynotus centrina has been kept successfully in captivity for the first time. Over a period of 24 months, the specimen preyed exclusively on the contents of elasmobranch egg cases, suggesting a specialized trophic niche.


Assuntos
Comportamento Alimentar , Tubarões/fisiologia , Animais , Cadeia Alimentar , Masculino
19.
Ann Chir Plast Esthet ; 60(6): 518-21, 2015 Dec.
Artigo em Francês | MEDLINE | ID: mdl-26362995

RESUMO

Pathomimia is defined as a dummy pathology self-induced deliberately and is neither associated with mental confusion nor disturbance of consciousness. This article reports a case of pathomimia in plastic surgery. One of our patients had intentionally injected physiological saline solution into her breast implants in order to increase their volume. Implants removal was necessary because of severe local inflammatory signs. Psychiatric assessment revealed body dysmorphic disorder (BDD) developed on an hysterical personality, which explained the self-induced injuries. This nosologic entity must be promptly identified because it's diagnosis remains problematic and a multidisciplinary medical management is essential.


Assuntos
Transtornos Dismórficos Corporais/psicologia , Implantes de Mama , Inflamação/induzido quimicamente , Inflamação/cirurgia , Comportamento Autodestrutivo/psicologia , Remoção de Dispositivo , Feminino , Humanos , Injeções/efeitos adversos , Comportamento Autodestrutivo/complicações , Cloreto de Sódio/administração & dosagem , Cloreto de Sódio/efeitos adversos , Adulto Jovem
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