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1.
J Dairy Sci ; 102(12): 11317-11327, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563309

RESUMO

Dairy farms producing 98% of the US milk supply participate in the Farmers Assuring Responsible Management (FARM) Animal Care Program. Producers who sell milk to cooperatives or processors participating in FARM must follow program standards. The objectives of this study were to assess producer perceptions about the knowledge, experience, and value of FARM and to determine whether perceptions differ based on demographics. A concurrent triangulation design was implemented through collecting quantitative and qualitative data using a 30-question survey instrument. Quantitative questions aimed to address project objectives, and qualitative data were provided through 1 open-ended survey question that asked participants what they thought the main goal of the FARM program was. Participants offered additional feedback through providing text in comment boxes, writing on the back of the survey, or writing a separate letter and returning it with their survey. Quantitative data were analyzed using principal components analysis and modeling, and qualitative data were analyzed through thematic analysis. Dairy producers from cooperatives or processors that participate in the FARM program were recruited via electronic and postal mail. A total of 487 respondents from 40 states completed the survey. Of the survey participants, 414 (85.0%) answered the open-ended question and 190 (39.0%) provided additional qualitative feedback. Thematic analysis revealed 5 main themes: distrust of program, producers on the defense, anger, efficiency, and nostalgia. Of respondents, 73.6% reported being knowledgeable about the FARM Animal Care Program. Greater level of formal education and larger herd size were associated with greater producer knowledge. More dairy producer input in the revisions of FARM was identified as a need by 83.3% of respondents. Although 89.3% of respondents reported positive experiences with evaluations and relationships with evaluators, 45.6% did not think that the program had value overall. Respondent age was positively associated with perceived value of FARM. Respondent age was also significant in determining the reasons why FARM was considered to be important. Results indicate that to increase buy-in and positive perceptions from producers, future versions of FARM should solicit producer input during the development of program standards, target specific producer demographics for program promotion, and address perceived communication deficits and program inequalities. Findings from this study can be used to inform future versions of the program.


Assuntos
Criação de Animais Domésticos , Indústria de Laticínios , Fazendeiros , Adulto , Idoso , Criação de Animais Domésticos/métodos , Animais , Bovinos , Indústria de Laticínios/métodos , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Leite , Percepção , Inquéritos e Questionários
2.
Ground Water ; 53(3): 356-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24826995

RESUMO

Thermal use of the shallow subsurface for heat generation, cooling, and thermal energy storage is increasingly gaining importance in reconsideration of future energy supplies. Shallow geothermal energy use is often promoted as being of little or no costs during operation, while simultaneously being environmentally friendly. Hence, the number of installed systems has rapidly risen over the last few decades, especially among newly built houses. While the carbon dioxide reduction potential of this method remains undoubted, concerns about sustainability and potential negative effects on the soil and groundwater due to an intensified use have been raised-even as far back as 25 years ago. Nevertheless, consistent regulation and management schemes for the intensified thermal use of the shallow subsurface are still missing-mainly due to a lack of system understanding and process knowledge. In the meantime, large geothermal applications, for example, residential neighborhoods that are entirely dependent up on shallow geothermal energy use or low enthalpy aquifer heat storage, have been developed throughout Europe. Potential negative effects on the soil and groundwater due to an intensive thermal use of the shallow subsurface as well as the extent of potential system interaction still remain unknown.


Assuntos
Meio Ambiente , Energia Geotérmica , Monitoramento Ambiental , Energia Geotérmica/efeitos adversos , Água Subterrânea/química , Solo/química , Temperatura , Movimentos da Água
3.
Andrologia ; 36(6): 366-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15541052

RESUMO

A prerequisite for the success of intracytoplasmic sperm injection (ICSI) is the use of viable sperm that will support oocyte activation and embryo development. Usually, spermatozoa are selected according to motility, which is a clear indication for viability. However, in cases with complete asthenozoospermia, it is impossible to select viable sperm by morphological means. Here we report for the first time on the use of a laser to discriminate between viable and dead immotile spermatozoa. The application of a single laser shot to the far end of the sperm tail causes a curling of the sperm tail only in viable sperm, similar to the reaction observed in the hypo-osmotic swelling test. Using this method for sperm selection prior to ICSI we achieved high fertilization and cleavage rates in cases with immotile sperm in fresh testicular biopsy material as well in cases with ejaculated immotile sperm. It is concluded that laser sperm interaction allows for the identification of viable but immotile spermatozoa.


Assuntos
Infertilidade Masculina/diagnóstico , Lasers , Motilidade dos Espermatozoides , Fase de Clivagem do Zigoto , Feminino , Fertilização , Humanos , Masculino , Osmose , Gravidez , Resultado da Gravidez , Injeções de Esperma Intracitoplásmicas , Espermatozoides/metabolismo , Espermatozoides/patologia , Espermatozoides/efeitos da radiação
4.
Hum Reprod ; 15(4): 846-52, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10739830

RESUMO

We evaluated the potential use of a non-contact, 1.48 microm wavelength diode laser for immobilization of human spermatozoa and permeabilization of the sperm membrane in different culture media. When we applied a single laser shot near to the middle region of the sperm tail, spermatozoa could be immobilized either temporarily or permanently, depending on the energy used. Above an energy of 2 mJ in polyvinylpyrrolidone and 2-3 mJ in culture medium, a reliable permanent immobilization was achieved by permeabilization of the sperm tail membrane. We then explored the use of a double laser shot technique. Spermatozoa were temporarily immobilized by a first laser shot applied near to the sperm tail followed by permeabilization with a second laser shot aimed directly at the sperm tail. This sequential approach yielded permanent immobilization at much lower energy values compared with the single shot technique. Following the injection of laser-treated spermatozoa, mouse oocytes underwent normal activation and pronuclear formation. We conclude that a non-contact 1.48 microm diode laser system can be used for immobilization of spermatozoa and for permeabilization of the sperm tail membrane. This laser procedure may offer an alternative to currently used sperm pretreatment prior to intracytoplasmic sperm injection.


Assuntos
Permeabilidade da Membrana Celular , Lasers , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Animais , Células Cultivadas , Meios de Cultura , Feminino , Humanos , Masculino , Camundongos , Oócitos/fisiologia , Injeções de Esperma Intracitoplásmicas , Espermatozoides/ultraestrutura
5.
Prostate Cancer Prostatic Dis ; 3(S1): S32, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12497140
6.
Andrologia ; 31(1): 49-53, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9949889

RESUMO

Improved procedure for efficient cryopreservation of single human spermatozoa in cell-free human zona pellucida is reported. We used a diode laser system for efficient and precise creation of a single hole into the zona pellucida of a degenerated or immature human oocyte. This allowed the extraction of the cytoplasm using a micropipette with a diameter of 10-15 microns. Through the same opening, human spermatozoa were inserted into the empty zona. We used motile and laser immobilized spermatozoa. Immobilized sperm were obtained by a single laser irradiation delivered in the vicinity of the sperm tail prior to insertion. This new immobilization procedure was shown to have no deleterious effect on membrane integrity and sperm viability. Following sperm transfer into the zona, the laser-drilled hole was closed with an oil droplet which was expelled from the micropipette during withdrawal to avoid loss of spermatozoa. This facilitated detection of the otherwise translucent zona during the cryopreservation procedure. After thawing, all cryopreserved zonae (20/20) could be successfully retrieved. Spermatozoa were recovered from the zona pellucida through the hole used for insertion. The rate of sperm recovery for initially motile spermatozoa was 80% vs. 92% for laser immobilized spermatozoa. Sperm viability was 81% and 84%, respectively, detected by a Hoechst stain. This technique makes cryopreservation of single human spermatozoa easy and feasible and appears beneficial for couples with severe male infertility and for those facing repeated surgical sperm extraction.


Assuntos
Criopreservação , Lasers , Preservação do Sêmen , Zona Pelúcida , Humanos
7.
Fertil Steril ; 69(3): 539-42, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9531893

RESUMO

OBJECTIVE: To investigate whether polar body biopsy can be performed after laser microdissection of the zona pellucida (ZP). DESIGN: Mouse zygotes were allocated randomly to three groups. The zygotes were subjected to laser microdissection of the ZP and polar body biopsy (group 1), laser microdissection alone (group 2), or no treatment (group 3). SETTING: University-based IVF program. PATIENT(S): Animal study. INTERVENTION(S): A hole was drilled in the ZP of mouse zygotes using a 1.48-micron noncontact diode laser. A microneedle was inserted and the polar body was aspirated. MAIN OUTCOME MEASURE(S): The efficacy of polar body biopsy after laser microdissection of the ZP was evaluated. RESULT(S): The laser diode beam allowed for precise drilling of a 14- to 18-micron hole in the ZP. Polar bodies could be aspirated without damaging the zygote and did not disintegrate during the biopsy. Zygotes developed to blastocysts and underwent the same hatching as control zygotes. Lower hatching rates were observed in untreated zygotes. CONCLUSION(S): Laser microdissection of the ZP with a noncontact laser system facilitates subsequent polar body biopsy. The use of blunt-ended micropipettes greatly reduces the risk of damage to the zygote or the polar body. This procedure makes polar body biopsy more accurate and effective for preimplantation genetic diagnosis.


Assuntos
Dissecação/métodos , Lasers , Zona Pelúcida/ultraestrutura , Animais , Blastocisto/fisiologia , Técnicas de Cultura , Feminino , Camundongos , Sucção , Zigoto/fisiologia
9.
Hum Reprod ; 11(5): 1043-8, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8671388

RESUMO

The safety of microdrilling the zona pellucida of mouse oocytes with a 1.48 microm diode laser has been investigated by determining the ability of mouse oocytes to fertilize in vitro and develop in vivo. Mice born after transfer of control and zona pellucida-microdrilled embryos into foster mothers were submitted to anatomical and immunohistochemical investigations, and their aptitude to breed was assessed in two subsequent generations. Decoronization of the oocytes with hyaluronidase induced a reduction of the fertilization and implantation rates, which was attributed to a zona hardening phenomenon. After laser zona pellucida microdrilling, these rates were restored to those obtained with embryos derived from untreated oocyte-cumulus complexes. Pups derived from zona pellucida microdrilled embryos were comparable with those obtained from control embryos, confirming the lack of deleterious effects of the laser treatment. In conclusion, the 1.48 microm diode laser allows safe microdrilling of the zona pellucida of mouse oocytes after decoronization with hyaluronidase. Based on the health of the F2 generation and the lack of neuroanatomical and neurochemical differences, we concluded that this technology may be investigated in the human, particularly when the zona pellucida represents the main impediment for fertilization or embryo hatching.


Assuntos
Fertilização in vitro/métodos , Lasers , Microcirurgia , Zona Pelúcida , Animais , Encéfalo/anatomia & histologia , Transferência Embrionária , Feminino , Imuno-Histoquímica , Masculino , Camundongos , Gravidez , Reprodução , Contagem de Espermatozoides , Medula Espinal/anatomia & histologia
10.
Lasers Surg Med ; 18(1): 52-62, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8850466

RESUMO

BACKGROUND AND OBJECTIVE: A non-touch laser-induced microdrilling procedure is studied on mouse zona pellucida (ZP). STUDY DESIGN/MATERIALS AND METHODS: A 1.48-microns diode laser beam is focused in a 8-microns spot through a 45x objective of an inverted microscope. Mouse zygotes, suspended in a culture medium, are microdrilled by exposing their ZP to a short laser irradiation and allowed to develop in vitro. RESULTS: Various sharp-edged holes can be generated in the ZP with a single laser irradiation. Sizes can be varied by changing irradiation time (3-100 ms) or laser power (22-55 mW). Drilled zygotes present no signs of thermal damage under light and scanning electron microscopy and develop as expected in vitro, except for a distinct eight-shaped hatching behavior. CONCLUSION: The microdrilling procedure can generate standardized holes in mouse ZP, without any visible side effects. The hole formation can be explained by a local photothermolysis of the protein matrix.


Assuntos
Terapia a Laser/instrumentação , Lasers , Microcirurgia/instrumentação , Zona Pelúcida/ultraestrutura , Animais , Blastocisto/ultraestrutura , Meios de Cultura , Técnicas de Cultura , Proteínas da Matriz Extracelular/ultraestrutura , Temperatura Alta , Lentes , Camundongos , Camundongos Endogâmicos , Microscopia/instrumentação , Microscopia Eletrônica de Varredura , Zigoto/ultraestrutura
11.
Fertil Steril ; 64(3): 604-11, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7641917

RESUMO

OBJECTIVE: To investigate the efficacy and safety of a small and affordable 1.48-microns continuous wave diode laser for zona pellucida (ZP) microdissection. DESIGN: Mouse and human oocytes and zygotes were submitted to ZP drilling. The hole characteristics and possible laser-induced structural alterations of the neighboring cytoplasm were investigated with scanning and transmission electron microscopy. The safety of the procedure was checked on control and drilled zygotes by determining their ability to develop in vitro and in vivo. SETTING: Collaborative study between three Swiss academic centers. INTERVENTIONS: The collimated diode laser beam was delivered through a 45x objective of an inverted microscope and focused through the culture dish and culture medium in 1- to 3-microns spots. MAIN OUTCOME MEASURE: Safety assessment of the laser drilling procedure. RESULTS: The 1.48-microns radiation achieves a rapid, precise, and easily controlled lysis of the ZP without any micromanipulative handling of the eggs. Different shapes of holes can be produced by varying the laser beam intersection site on the ZP, laser power, and irradiation time. The energy needed to drill holes of a given diameter is greater for zygotes than for oocytes. Safety of the drilling procedure is confirmed by the lack of damage at the ultrastructural and biologic levels. CONCLUSIONS: The low-cost 1.48-microns diode laser allows an easy, objective-driven, nontouch microdissection of the ZP. The procedure is safe, as drilled embryos give rise to normal and fertile offspring.


Assuntos
Lasers , Micromanipulação/métodos , Zona Pelúcida , Animais , Citoplasma/ultraestrutura , Feminino , Fertilização in vitro , Humanos , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Gravidez , Resultado da Gravidez , Zona Pelúcida/ultraestrutura , Zigoto/fisiologia , Zigoto/ultraestrutura
12.
Ultrasound Med Biol ; 21(1): 97-103, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7754583

RESUMO

The damage induced by an extracorporeal shock wave lithotripter is observed with a fiber optic stress sensing technique. When a stone is placed in the focus, besides the expected stress induced by the incoming shock wave emitted by the ESWL apparatus, a second delayed stress is observed some hundreds of microseconds later. The second stress is induced by a shock wave generated at the collapse of a cavitation bubble. Partial reflection of the incoming shock wave at the stone boundary is at the origin of the large cavitation bubble formation. Sensing fiber fracture results always from the second shock wave due to the collapse of the cavitation bubble. Thus the largest stress is generated at the collapse. When no target is placed in the focus of the lithotripter, no large cavitation bubble is formed and no delayed shock wave is observed. Our results demonstrate unambiguously the decisive role of cavitation in ESWL procedures.


Assuntos
Cálculos/fisiopatologia , Litotripsia , Acústica/instrumentação , Fenômenos Biofísicos , Biofísica , Cálculos/química , Tecnologia de Fibra Óptica/instrumentação , Humanos , Lasers , Fibras Ópticas , Polivinil , Pressão , Reprodutibilidade dos Testes , Estresse Mecânico , Fatores de Tempo
13.
Lasers Surg Med ; 16(2): 134-46, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7769958

RESUMO

BACKGROUND AND OBJECTIVE: Flashlamp pumped dye (FPDL), Q-switched Nd:YAG, and alexandrite lasers are the most clinically used laser lithotriptors. Although calculi are fragmented by laser induced mechanical stresses for all lithotriptors, different fragment sizes and fragmentation efficiencies have been reported. In this work the effect of the pulse duration and pulse shape on the fragmentation processes is studied. MATERIAL AND METHODS: Fragmentation processes are characterized on model stones and on sensing target fibers. Stone fragmentation and cavitation bubble generation are observed by video flash photography. Shock wave occurrence and strength are monitored with an hydrophone. RESULTS: For the FPDL, stone fragmentation is induced by the collapse of the large cavitation bubble formed. For the Q-switched Nd:YAG, fragmentation is already observed during the laser pulse, at the plasma onset, although further fragmentation can occur at the bubble collapse. For pulse durations corresponding to the alexandrite, an intermediate fragmentation regime is observed. CONCLUSION: For the first time the physical basis of the observed differences in the fragmentation efficiencies of current laser lithotriptors is described. For nanosecond durations the fragmentation processes are governed by plasma induced shock waves. On the contrary, for microsecond durations fragmentation is governed by cavitation. The high fragmentation efficiency of microsecond lasers is due to a high laser energy transfer into cavitation.


Assuntos
Litotripsia a Laser , Modelos Teóricos , Técnicas In Vitro , Litotripsia a Laser/instrumentação , Teste de Materiais , Pressão , Dióxido de Silício/efeitos da radiação , Estresse Mecânico , Resistência à Tração , Cálculos Urinários , Gravação em Vídeo
14.
Acta Psychiatr Scand ; 90(2): 102-8, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7976454

RESUMO

This study aimed to assess the prevalence and treatment modalities of elderly practice attenders. A total of 330 patients aged over 65 years were investigated with a questionnaire in general practice. To assess insomnia, operationalized diagnostic criteria according to DSM-III-R were applied. Twenty-three percent of the elderly patients suffered from severe, 17% from moderate and 17% from mild insomnia. More than 80% of the patients reported suffering from insomnia for 1-5 years or longer, which indicates a chronic course. Elderly patients showed unrealistic expectations concerning duration of sleep and spend more time in bed than they realistically can expect to sleep. More than half of the elderly patients reported habitual daytime napping. Sleep-disturbed elderly patients did not differ significantly from good sleepers in their habit of taking daytime naps, but even when taking daytime naps, good sleepers slept significantly longer than the sleep-disturbed patients. A significant association was found between insomnia and mental disorders, i.e., depression and organic brain syndrome according to the diagnosis of the general physician. In about half of the cases the primary care physician was not aware that the elderly patient suffered from severe insomnia. More than half of the elderly severe insomniacs took prescribed hypnotics habitually, mainly benzodiazepines.


Assuntos
Ansiolíticos/uso terapêutico , Hipnóticos e Sedativos/uso terapêutico , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Ansiolíticos/efeitos adversos , Benzodiazepinas , Ritmo Circadiano/efeitos dos fármacos , Uso de Medicamentos , Medicina de Família e Comunidade , Feminino , Alemanha/epidemiologia , Humanos , Hipnóticos e Sedativos/efeitos adversos , Masculino , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Fases do Sono/efeitos dos fármacos
15.
Eur Arch Psychiatry Clin Neurosci ; 242(6): 329-36, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8323982

RESUMO

The aim of the study was to assess prevalence and treatment modalities of insomnia in general practice. To investigate the course of insomnia, a longitudinal study design was adopted. Two thousand five hundred and twelve patients (age 18-65 years) were investigated with a questionnaire in general practice (T1). Four months later (T2) and again 2 years later (T3) a questionnaire was sent to all patients who had complained about severe insomnia at the time of the first inquiry. To assess insomnia, operationalized diagnostic criteria were applied (DSM-III-R). Eighteen point seven percent suffered from severe, 12.2% suffered from moderate and 15% suffered from mild insomnia. In the course of 2 years insomnia appeared as a chronic health problem. A high comorbidity of severe insomnia was found with chronic somatic and psychiatric disorders, especially with depression. Of the severely insomniac patients, 23.9% used prescribed hypnotics habitually, mainly benzodiazepines. The use of prescribed hypnotics remained rather stable during the whole study period. More than half of the patients reported a daily use of the hypnotics for 1-5 years or longer, but only 22% of the severely insomniac patients reported at the time of the third inquiry a significant improvement of insomnia due to the administration of sleeping pills. Thus, the long-term administration of benzodiazepine hypnotics seems to be an inadequate treatment strategy in chronic insomnia. Whether the occurrence of rebound insomnia after benzodiazepine withdrawal may be one of the main factors for chronic hypnotic use requires discussion.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Medicina de Família e Comunidade , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Adolescente , Adulto , Idoso , Benzodiazepinas/uso terapêutico , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Transtornos Mentais/complicações , Pessoa de Meia-Idade , Prevalência , Escalas de Graduação Psiquiátrica , Transtornos Psicofisiológicos/complicações , Índice de Gravidade de Doença , Fatores Sexuais , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Inquéritos e Questionários
16.
Helv Chir Acta ; 58(3): 323-5, 1991 Sep.
Artigo em Francês | MEDLINE | ID: mdl-1769853

RESUMO

A collaborative study about a pulsed dye laser Rhodamin 590 was undergone, 2 years ago, between the laser application center of EPFL and both urological departments of the university of Geneva and the university of Lausanne. First clinical results are presented. Ten patients have been treated for various ureteral stones, mainly calcium oxalate stones. Laser fragmentation was successful in seven cases. No serious complication was noted. Fragmentation efficiency seems better with a 320 microns fiber than with a 200 microns fiber.


Assuntos
Litotripsia/instrumentação , Cálculos Ureterais/terapia , Adulto , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
17.
Schweiz Med Wochenschr ; 119(26): 941-3, 1989 Jul 01.
Artigo em Francês | MEDLINE | ID: mdl-2572048

RESUMO

In the last few years the treatment of urinary calculi has been dramatically transformed by new endoscopic methods and extracorporeal shock wave lithotripsy. Laser lithotripsy is in keeping with this evolution. After a short description of the principle of laser lithotripsy, a prototype pulsed dye laser lithotriptor, developed by the Centre d'applications laser, Ecole polytechnique fédérale de Lausanne, is presented. This device is compared with other lasers proposed for the same application.


Assuntos
Cálculos Renais/terapia , Terapia a Laser , Litotripsia a Laser , Litotripsia/instrumentação , Previsões , Humanos
18.
Z Geburtshilfe Perinatol ; 183(5): 339-42, 1979 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-543183

RESUMO

In the investigation of possible myocardial damage, the assay of the heart specific isoenzyme kreatinkinase MB has established itself as a highly sensitive proof of a heart necrosis. In patients who underwent stationary treatment for premature contractions, the CK-activity was measured in the initial phase of tocolysis and additionally right before the therapy was ended. There was no laboratory indication of any heart damage due to tocolytic treatment.


Assuntos
Creatina Quinase/metabolismo , Etanolaminas/uso terapêutico , Fenoterol/uso terapêutico , Trabalho de Parto Prematuro/tratamento farmacológico , Feminino , Coração/efeitos dos fármacos , Humanos , Isoenzimas , Potássio/sangue , Gravidez
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