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In the spiny lobster Panulirus homarus (Linnaeus) the spermatophoric mass consists of a highly convoluted tube, containing the sperm mass and a gelatinous matrix. The spermatophoric components have their origin in the proximal vas deferens and the completed spermatophoric mass is stored within the distal dilated part of the vas deferens. In the proximal vas deferens the inner glandular epithelial cells give rise to leaf-like typhlosoles which gradually diminish in size and finally disappear in the distal vas deferens. The secretions originating from the typhlosole form the outer gelatinous matrix of the spermatophoric mass. Histochemical observations reveal that the wall of the spermatophore tube consists of neutral mucopolysaccharide, whereas the sperm mass and the gelatinous matrix are rich in acidic mucopolysaccharides. Both polyacrylamide gel electrophoresis and agarose gel electrophoresis were used to separate the acidic mucopolysaccharide (AMPS) complexed with the proteins and the simple proteins. In addition, AMPS have been isolated following the method of Rahemtulla and Lovtrup (1974) and used for electrophoresis. In both the polyacrylamide gel electrophoresis and agarose gel electrophoresis, the extracted acid mucopolysaccharides give only a single fraction which, in comparison with the standard acid mucopolysaccharides, corresponds to chondroitin sulphate. The functional significance of the chondroitin sulphate and neutral mucopolysaccharides in the spermatophoric components of P. homarus is discussed in relation to their functional role in spermatophore hardening and protection of the delicate spermatozoa during their prolonged storage on the sternum of the female.  相似文献   
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This paper describes the MICORE approach to quantify for nine field sites the crucial storm related physical hazards (hydrodynamic as well as morphodynamic) in support of early warning efforts and emergency response.As a first step historical storms that had a significant morphological impact on a representative number of sensitive European coastal stretches were reviewed and analysed in order to understand storm related morphological changes and how often they occur around Europe. Next, an on-line storm prediction system was set up to enable prediction of storm related hydro- and morphodynamic impacts. The system makes use of existing off-the-shelf models as well as a new open-source morphological model. To validate the models at least one year of fieldwork was done at nine pilot sites. The data was safeguarded and stored for future use in an open database that conforms to the OpenEarth protocols.To translate quantitative model results to useful information for Civil Protection agencies the Frame of Reference approach ( [Van Koningsveld et al., 2005] and [Van Koningsveld et al., 2007] ) was used to derive Storm Impact Indicators (SIIs) for relevant decision makers. The acquired knowledge is expected to be directly transferred to the civil society trough partnerships with end-users at the end of the MICORE project.  相似文献   
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This paper reports the feasibility of using surface mount adhesives to produce low temperature microchannel arrays in a wide variety of metals. Sheet metal embossing and chemical etching processes have been used to produce sealing bosses that eliminate channel laminae, resulting in approximately 50% material savings over traditional methods. An assembly process using adhesive dispense and cure is outlined to produce leak-free devices. Optimal fill ratios were determined to be between 1.1 and 1.25. Bond strength investigation reveals robustness to surface conditions and a bond strength of 5.5–8.5 MPa using a 3X safety factor. Dimensional characterization reveals a two sigma (95%) post-bonded channel height tolerance under 10% after bonding. Patterning tolerance and surface roughness of the laminae faying surfaces were found to have a significant influence on the final post-bonded channel height. Leakage and burst pressure testing on several samples has established confidence that adhesive bonding can produce leak-free joints. Operating pressures up to 413 kPa have been satisfied, equating to tensile pressure on bond joints of 1.9 MPa. Higher operating pressures can be accommodated by increasing the bond area of devices.  相似文献   
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Introduction

The rate for work related accidents in the Spanish mining sector is notably higher than in other countries such as the United States. It produces a very negative impact on the mining industry. This paper is the report of a study on serious and fatal accidents in Spanish mining from 1982-2006. It is based on the reports of 212 accidents (serious or fatal) carried out by the General Management of Energy and Mining of Catalonia (Spain). Method: The high work-related accident rate in the Spanish mining sector makes it necessary to carry out an analysis and research that can shed light on the causes of this high rate; this is the only way that a solution can be found. The study is based on Feyer and Williamson's analysis of accident causes, as they apply to 212 accidents. The types and causes of the accidents are coded according to the coding system used by the Spanish National Institute for Safety and Hygiene in the Workplace, which allows us to identify a series of direct causes and contributing factors in different accidents. Results If all the causes and factors that are present in the accidents are known, we are able to look for appropriate solutions to reduce them as much as possible. In short, we are able to come up with a series of conclusions that expose the weak links in the management of accident prevention in companies. This is helpful in the struggle to reduce work injuries in the Spanish mining sector.  相似文献   
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Objective

To examine trends in alcohol consumption and alcohol-related crashes among people younger than 21 in the United States and to review evidence on the effects of minimum legal drinking age (MLDA) laws.

Methods

Trends in alcohol-related crashes and alcohol consumption among young people were examined, and studies on the effects of lowering and raising the drinking age were reviewed.

Results

MLDA laws underwent many changes during the 20th century in the United States. Since July 1988, the MLDA has been 21 in all 50 states and the District of Columbia. Surveys tracking alcohol consumption among high school students and young adults found that drinking declined since the late 1970 s, and most of the decline occurred by the early 1990 s. These were the years when states were establishing, or reinstating, a MLDA-21. Among fatally injured drivers ages 16-20, the percentage with positive BACs declined from 61% in 1982 to 31% in 1995, a bigger decline than for older age groups; declines occurred among the ages directly affected by raising MLDAs (ages 18-20) and among young teenagers not directly affected (ages 16-17). Almost all studies designed specifically to gauge the effects of drinking age changes show MLDAs of 21 reduce drinking, problematic drinking, drinking and driving, and alcohol-related crashes among young people. Yet many underage people still drink, many drink and drive, and alcohol remains an important risk factor in serious crashes of young drivers, especially as they progress through the teenage years. Stepped-up enforcement of MLDA and drinking and driving laws can reduce underage drinking. Recent efforts to lower MLDAs to 18 and issue licenses to drink upon completion of alcohol education have gained local and national media attention. There is no evidence that alcohol education can even partially replace the effect of MLDA-21.

Conclusions

The cause and effect relationship between MLDAs of 21 and reductions in highway crashes is clear. Initiatives to lower the drinking age to 18 ignore the demonstrated public health benefits of MLDAs of 21.

Impact on Industry

Lowering the drinking age to 18 will increase highway crash deaths among young people.  相似文献   
19.

Objective

This study compares construction industry groups in Washington State by injury severity and cost, and ranks industry groups according to potential for prevention.

Methods

All Washington State workers' compensation compensable claims with date of injury between 2003 and 2007 were classified into North American Industrial Classification System (NAICS) industry groups. Claims were then aggregated by injury type and industry groups were ranked according to a prevention index (PI). The PI is the average of the rank orders of the claim count and the claim incidence rate. A lower PI indicates a higher need for prevention activities. The severity rate was calculated as the number of days of time loss per 10,000 full-time equivalents (FTEs).

Results

For all injury types, construction industry groups occupy 7 of the top 15 PI ranks in Washington State. The severity rate among construction industry groups was twice that for non-construction groups for all injury types. Foundation, structure, and building exterior contractors (NAICS 2381) ranked highest in prevention potential and severity among construction industry groups for most common injury types including falls from elevation, fall on same level, struck by/against, and musculo-skeletal disorders of the neck, back, and upper extremity (WMSDs). Median claim costs by injury type were generally higher among construction industry groups.

Conclusions

The construction industry in Washington State has a high severity rate and potential for prevention. The methods used for characterizing these industry groups can be adapted for comparison within and between other industries and states.

Impact on Industry

These data can be used by industry groups and employers to identify higher cost and higher severity injury types. Knowledge about the relative frequencies and costs associated with different injury types will help employers and construction industry associations make better informed decisions about where prevention efforts are most needed and may have the greatest impact. The results of this study can also be used by industry stakeholders to cooperatively focus on high cost and high severity injuries and explore best practices, interventions, and solutions as demonstrated by efforts to prevent musculoskeletal disorders in masonry (Entzel, Albers, & Welch, 2007). Initiating construction industry groups to focus on high cost and high severity injuries may also help prevent other types of injuries.  相似文献   
20.

Introduction

The purpose of this study was to analyze linked crash and hospital data to determine the effect that enactment of a standard enforcement safety belt law in Ohio would have on hospital charges and direct medical costs due to motor-vehicle crashes, focusing on the impact to the state's Medicaid system.

Method

The linkage and analysis was conducted as part of the Ohio Crash Outcome Data Evaluation System (CODES) program. Current safety belt usage in Ohio stands at 82% with its secondary enforcement safety belt law.

Results

Assuming an increase in usage to 92% through standard enforcement, over $15.3 million in medical costs to Medicaid for injuries that occur in a single year could be prevented over a 10-year period. Cumulative savings could reach more than $91.2 million during the 10-year period. In addition, 161 fatalities could have been prevented in one year had all unbelted occupants who sustained a fatal injury instead chosen to wear their safety belt.

Summary and Impact on Industry

Clearly, substantial progress can be made in reducing the number of deaths and injuries, as well as medical costs associated with motor-vehicle crashes, by strengthening safety belt laws and increasing safety belt usage in Ohio.  相似文献   
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