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1.
HardwareX ; 11: e00307, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35518280

RESUMO

Future global climate change with higher mean temperatures and increased intensity and frequency of heatwaves as extreme weather events will affect aquatic ecosystems with, yet, unpredictable severity and consequences. Although models suggest increased risk of species extinction up to the year 2050 for series of different climate change scenarios, environmental complexity may result in unconsidered effects of future temperature alterations on ecosystems. Apart from these environmental changes, additional anthropogenic stressors, e.g. chemical release, may cause unprecedented interaction effects on ecosystems. Ongoing efforts to better understand such temperature-chemical interaction effects comprise almost exclusively experimental designs using constant temperature regimes instead of environmentally realistic daily temperature variations. In this paper we describe an Arduino-based temperature and heatwave control device (TENTACLE) that is transportable, inexpensive, multifunctional, and easily reproducible. TENTACLE offers water temperature monitoring and manipulation of up to 3 different climate change-related scenarios: i) natural (ambient) sinusoidal fluctuations (laboratory applications), ii) elevated fluctuations, and iii) heatwaves as extreme events. The use of replaceable heating elements and low-cost materials suitable for field studies creates a high flexibility for researchers who may conduct in- or out-door, small- or large-scale, fresh- or salt-water experiments at different geographical locations.

2.
Sensors (Basel) ; 17(6)2017 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-28574466

RESUMO

Infrared imaging technology, used both to study deep-space bodies' radiation and environmental changes on Earth, experienced constant improvements in the last few years, pushing data converter designers to face new challenges in terms of speed, power consumption and robustness against extremely harsh operating conditions. This paper presents a 96.6-dB-SNDR (Signal-to-Noise-plus-Distortion Ratio) 50-kHz-bandwidth fourth-order single-bit switched-capacitor delta-sigma modulator for ADC operating at 1.8 V and consuming 7.9 mW fit for space instrumentation. The circuit features novel Class-AB single-stage switched variable-mirror amplifiers (SVMAs) enabling low-power operation, as well as low sensitivity to both process and temperature deviations for the whole modulator. The physical implementation resulted in a 1.8-mm2 chip integrated in a standard 0.18-µm 1-poly-6-metal (1P6M) CMOS technology, and it reaches a 164.6-dB Schreier figure of merit from experimental SNDR measurements without making use of any clock bootstrapping,analogcalibration,nordigitalcompensationtechnique. Whencoupledtoa2048×2048 IR imager, the current design allows more than 50 frames per minute with a resolution of 16 effective number of bits (ENOB) while consuming less than 300 mW.

4.
J Trauma ; 71(1 Suppl): S114-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21795869

RESUMO

BACKGROUND: The purpose of this case series was to review the management of burn patients who requested ultrarapid opioid detoxification under anesthesia after extended duration of narcotic use for chronic pain related to burn injury. METHODS: The treatment plan of six opioid-dependent burn patients was analyzed to assess the effectiveness of our detoxification practice to date. Demographic and clinical information was used to characterize the patient population served: age, burn size, injury severity, duration of narcotic use before detoxification intervention, and length of hospitalization stay. Daily narcotic consumption, in morphine equivalent units, was noted both before and after detoxification. RESULTS: Six burn patients (average age, 31 years) underwent detoxification at the Burn Center during a hospitalization lasting between 1 day and 2 days. Average burn size was 38% total body surface area (range, 17-65); average Injury Severity Score was 30 (range, 25-38). Mean duration of narcotic use was 672 days (range, 239-1,156 days); average use of narcotics at time of detoxification was >200 units daily. Mean outpatient consumption for opioids after the intervention was minimal (<25 units/d). No complications were noted during any procedures. CONCLUSIONS: The results of ultrarapid opioid detoxification under anesthesia suggests that it is safe and effective for treating opioid addiction in military burn casualties when a coordinated, multidisciplinary approach is used. Safety and effectiveness to date validate current practice and supports incorporation into clinical practice guidelines. Further clinical research is warranted to identify those patients who may benefit most from detoxification and to determine the timing of such treatment.


Assuntos
Analgésicos Opioides/efeitos adversos , Queimaduras/tratamento farmacológico , Dor/tratamento farmacológico , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Adulto , Analgésicos Opioides/uso terapêutico , Queimaduras/complicações , Humanos , Masculino , Militares , Naloxona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Dor/etiologia , Estados Unidos
5.
Eur J Orthod ; 33(1): 1-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20106997

RESUMO

Wound contraction and scar formation after cleft palate repair lead to growth impairment of the maxilla and midface. Myofibroblasts play a key role in these processes. The application of an interferon-γ (IFN-γ)-loaded collagen scaffold after surgery might reduce the differentiation of myofibroblasts. In this study, the tissue response to IFN-γ-loaded collagen scaffolds was evaluated after implantation in the palate of rats. Scaffolds, with or without IFN-γ, were implanted submucoperiosteally in the palate of two groups of 25 five-week-old male Wistar rats. Groups of five rats were sacrificed at 1, 2, 4, 8, and 16 weeks post-implantation and processed for histological analyses. On haematoxylin and eosin-stained sections, the cell density and number of giant cells within the scaffolds were determined. Blood vessels, inflammatory cells, and myofibroblasts were detected by immunohistochemistry. The data for cell density, blood vessels, and giant cells were compared with a two-way analysis of variance. The scores for myofibroblasts and inflammation were compared by a rank sum test. A mild and rapidly subsiding inflammatory and foreign body response was found in both groups. Angiogenesis had already begun after 1 week, showed a peak after 4 weeks, and declined thereafter. IFN-γ induced a faster influx of host cells and a major reduction in myofibroblast numbers. The scaffolds might be suitable for future applications in oral surgery.


Assuntos
Colágeno Tipo I , Interferon gama/uso terapêutico , Mucosa Bucal/cirurgia , Miofibroblastos/efeitos dos fármacos , Palato/cirurgia , Alicerces Teciduais , Actinas/análise , Animais , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Colágeno Tipo IV/análise , Reação a Corpo Estranho/patologia , Células Gigantes/efeitos dos fármacos , Inflamação , Masculino , Mucosa Bucal/irrigação sanguínea , Mucosa Bucal/citologia , Mucosa Bucal/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Palato/irrigação sanguínea , Palato/citologia , Palato/efeitos dos fármacos , Ratos , Ratos Wistar , Proteínas Recombinantes , Fatores de Tempo
6.
J Oral Pathol Med ; 38(8): 630-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19473448

RESUMO

BACKGROUND: Wound contraction and scar formation after cleft palate repair impair the growth of the maxilla. The implantation of a growth factor-loaded scaffold might solve these problems. METHODS: The tissue response to fibroblast growth factor (FGF)-2 loaded collagen scaffolds was evaluated after implantation in the palate of rats. Scaffolds, with and without FGF-2, were implanted submucoperiosteally in the palate of 25 rats and evaluated after up to 16 weeks. On hematoxylin and eosin (H&E)-stained sections, the cell density and the number of giant cells within the scaffolds were quantified. Infiltration of inflammatory cells, myofibroblasts, and the number of blood vessels were quantified after immunohistochemistry. RESULTS: The cell density was significantly higher in the FGF-2 group up to 4 weeks after implantation (102% at 2 weeks, P < 0.001). The number of blood vessels was also significantly higher in the FGF-2 group at 1 and 2 weeks (316% at 1 week, P = 0.003), but the myofibroblast score was lower (100% at 2 weeks, P = 0.008). A comparable mild and rapidly subsiding inflammatory response and foreign body reaction were found in both groups. CONCLUSION: FGF-2-loaded scaffolds displayed a faster influx of host cells, an increased rate of vascularization, and a reduced differentiation of myofibroblasts. These scaffolds might therefore be highly suitable for intra-oral reconstructions, such as cleft palate repair.


Assuntos
Fator 2 de Crescimento de Fibroblastos/fisiologia , Regeneração Tecidual Guiada/métodos , Neovascularização Fisiológica/fisiologia , Palato/fisiologia , Alicerces Teciduais , Animais , Movimento Celular , Colágeno Tipo I , Sistemas de Liberação de Medicamentos , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Fibroblastos/fisiologia , Implantes Experimentais , Estudos Longitudinais , Masculino , Mucosa Bucal/irrigação sanguínea , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/fisiologia , Mucosa Bucal/cirurgia , Miócitos de Músculo Liso/fisiologia , Neovascularização Fisiológica/efeitos dos fármacos , Palato/irrigação sanguínea , Palato/efeitos dos fármacos , Palato/cirurgia , Ratos , Ratos Wistar , Procedimentos de Cirurgia Plástica/métodos , Estatísticas não Paramétricas , Engenharia Tecidual/métodos
7.
J Craniofac Surg ; 19(3): 599-608, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18520371

RESUMO

Scar formation after repair of the cleft palate leads to growth impairment of the upper jaw and midface. The implantation of a suitable scaffold during surgery may reduce this adverse effect. However, little is known about tissue reactions to scaffolds implanted in the oral cavity. Our goal was to analyze the tissue reactions to cross-linked type I collagen scaffolds after submucoperiosteal implantation in the palate of rats. Collagen type I scaffolds were implanted in the palate of 25 male Wistar rats. Groups of 5 rats were killed consecutively after 1, 2, 4, 8, and 16 weeks and were processed for histologic and immunohistochemical analyses. After 1 and 2 weeks, 3 rats from the sham group were also killed. On hematoxylin and eosin-stained sections, the cell density and the number of giant cells were determined. Blood vessels, inflammation, and the presence of myofibroblasts were detected by immunohistochemistry. An influx of inflammatory cells started after 1 week but had completely subsided after 8 weeks. Myofibroblasts were observed within the scaffolds only in the first 2 weeks. Angiogenesis already started after 1 week and showed a peak after 4 weeks, slowly declining afterward. The scaffolds were gradually integrated within the host tissue and only elicited a mild and transient inflammatory response. The scaffolds were biocompatible and seemed to be promising for future applications in cleft palate surgery.


Assuntos
Cicatriz/prevenção & controle , Colágeno Tipo I , Palato/cirurgia , Engenharia Tecidual/métodos , Alicerces Teciduais , Actinas/análise , Análise de Variância , Animais , Colágenos Fibrilares/biossíntese , Fibroblastos/citologia , Reação a Corpo Estranho , Implantes Experimentais , Masculino , Mucosa Bucal/cirurgia , Células Musculares/citologia , Neovascularização Fisiológica , Ratos , Ratos Wistar
8.
Arch Oral Biol ; 53(4): 376-87, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18093570

RESUMO

OBJECTIVE: To compare the tissue reactions to implanted collagen scaffolds in the palate and the skin of rats. DESIGN: Crosslinked collagen scaffolds were implanted submucoperiosteally in the palate, and subcutaneously on the skull and on the back of 25 rats and evaluated after up to 16 weeks. On H&E-stained sections, the cell density and the number of giant cells within the scaffolds were determined. Blood vessels, inflammatory cells, and myofibroblasts were detected by immunohistochemistry. RESULTS: A faster ingrowth of myofibroblasts and blood vessels in the palate was found during the first week compared with the skin. A more severe inflammatory response was initially found in the back skin. Furthermore, about twice as much giant cells were present in these scaffolds. CONCLUSION: The oral environment seems to promote the ingrowth of myofibroblasts and blood vessels into the scaffolds. Mechanical stimuli seem to enhance the initial inflammatory response. Overall, the scaffolds were gradually integrated within the host tissue, eliciting only a transient inflammatory response. The scaffolds were biocompatible and are promising for future applications in oral surgery.


Assuntos
Implantes Absorvíveis , Regeneração Tecidual Guiada/métodos , Mucosa Bucal/citologia , Pele/citologia , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis , Colágeno Tipo I , Fibroblastos/citologia , Células Gigantes/citologia , Masculino , Mucosa Bucal/irrigação sanguínea , Neovascularização Fisiológica , Palato/irrigação sanguínea , Palato/citologia , Ratos , Ratos Wistar , Pele/irrigação sanguínea , Cicatrização
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