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71.
Many Monty Python fans remember fondly the infamous musical sketch celebrating the versatility of the meat product Spam. However, others of us are less favourably disposed to the modern day, information society version of ‘spam’: junk E-mail. For many users of the Internet, junk E-mail is becoming a significant nuisance that existing laws do not prevent, but regulations will soon be introduced to make it more difficult for people to send.  相似文献   
72.
Under a recent controversial law approved at the federal level in the USA, some software vendors may have the right to remotely disable software if they believe that the software user is in breach of their licence. It is one of a number of rights included in the Uniform Computer Information Transactions Act (UCITA) which critics argue unfairly swings the law in favour of software vendors. If UCITA is ratified by the US States, companies who sell or purchase software under agreements subject to US law may feel its impact in England.  相似文献   
73.
Verifying the integrity of a hard disk is an important concern in computer forensics,as the law enforcement party needs to confirm that the data inside the hard disk have not been modified during the investigation.A typical approach is to compute a single chained hash value of all sectors in a specific order.However,this technique loses the integrity of all other sectors even if only one of the sectors becomes a bad sector occasionally or is modified intentionally.In this paper we propose a k-dimensional hashing scheme,kD for short,to distribute sectors into a kD space,and to calculate multiple hash values for sectors in k dimensions as integrity evidence.Since the integrity of the sectors can be verified depending on any hash value calculated using the sectors,the probability to verify the integrity of unchanged sectors can be high even with bad/modified sectors in the hard disk.We show how to efficiently implement this kD hashing scheme such that the storage of hash values can be reduced while increasing the chance of an unaffected sector to be verified successfully.Experimental results of a 3D scheme show that both the time for computing the hash values and the storage for the hash values are reasonable.  相似文献   
74.
75.
Twentieth-century historic industrial activity in Cornwall, ON loaded high amounts of metals and metalloids to the St. Lawrence River. Despite industrial improvements and the eventual closure of point-source polluters, sedimentary contamination in the Cornwall waterfront remains above provincial guidelines, causing concern for ecosystem management. We analysed chironomid (Order: Diptera) subfossils from modern-day surface-sediment samples and a sediment core from the Cornwall waterfront in order to better understand historic pollution impacts and potential recovery. Modern-day chironomid assemblages were diverse (48 genera, >70 species) and overall assemblage structure was weakly related to sedimentary zinc concentrations, with Procladius, Paratanytarsus, and Ablabesmyia identified as zinc-tolerant and Rheotanytarsus, Polypedilum and Paratendipes identified as zinc-sensitive. The sediment core showed peak total mercury (THg) concentrations were an order of magnitude higher than in modern-day surface sediments. In sections of the core below 10 cm in depth, THg concentrations were high (~30–50 µg/g) and chironomids were nearly absent from the record. Above 10 cm (c. 1980) THg concentrations decreased and chironomid taxa returned in low abundances. Subsequent intervals displayed an increase in diversity, abundance, and the relative abundance of metal-sensitive taxa. This study provides evidence of ecological change which co-occurs with Cornwall’s historic industrial activity and indicates progress toward related ecological goals identified in the current management strategy.  相似文献   
76.
Recent studies have shown that unsafe driver acts can be classified into two distinct categories (i.e.. errors and violations) entailing different measures for reducing road traffic accidents. A survey of over 1,400 drivers in Greece is reported in which a variety of aberrant driving behaviours have been identified. The present study has confirmed the results of earlier studies in the driving populations of Britain. Australia and Sweden that errors and violations are the major determinants in the factor structure of aberrant behaviours. Three types of violations were identified including, highway code-, aggressive- and parking-violations (or situational violations). Mistakes and lapses were two major forms of errors. The factor analysis identified another two classes of behaviour that could not be accounted for very well by the error-violation distinction. One class of behaviours referred to a state of low preparedness and negligence while the other class referred to communication errors and 'social disregard' for the other road users. Each class of behaviour was found to have different demographic correlates. Finally, accident liability was predicted by self-reported tendency to commit highway-code violations, but not by tendency to make errors due to failures of judgement (i.e.. mistakes) or lapses. Aggressive violations were significantly related to involvement in speeding convictions and law-breaking whilst highway-code violations were related to speeding convictions only.  相似文献   
77.
Glucagon-like peptide-2 (GLP-2) enhances intestinal growth and absorption in mature animals, and glucocorticosteroids (GC) increase the sugar and lipid uptake in adult animals. However, the role of GC and GLP-2 in the ontogeny of lipid absorption is unknown. We hypothesized that GLP-2 and the GC dexamethasone (DEX), when administrated to rat dams during pregnancy and lactation, would enhance lipid uptake in the off-spring. Rat dams were treated in the last 10 d of pregnancy and during lactation with GLP-2 [0.1 μg/g/d subcutaneous (sc)], DEX (0.128 μg/g/d sc), GLP-2+DEX, or a placebo. Sucklings were sacrificed at 19–21 d of age, and weanlings were sacrificed 4 wk later. Lipid uptake was assessed using an in vitro ring uptake method. Although DEX and GLP-2+DEX increased the jejunal mass, the jejunal lipid uptake was unchanged. In contrast, GLP-2, DEX, and GLP-2+DEX reduced the ileal lipid uptake in suckling and weanling rats. This reduction was not due to alterations in intestinal morphology or to changes in fatty acid-binding protein abundance, but it was partially explained by an increase in the effective resistance of the intestinal unstirred water layer. In sucklings, DEX dramatically reduced the jejunal lipid uptake to levels similar to those seen in weanlings, such that the normal ontogenic decline in lipid uptake was not observed. Giving dams GLP-2 or DEX during pregnancy and lactation reduced lipid uptake in the offspring, and this persisted for at least 1 mon. The impact this may have on the nutritional well-being of the animal in later life is unknown.  相似文献   
78.
Animal fats are preserved at archaeological sites in association with unglazed pottery, human and animal remains, and other deposits or hoards. High-temperature gas chromatography (HT-GC) and combined HT-GC/mass spectrometry (HT-GC/MS) has confirmed the presence of animal fats in lipid extracts of artifacts. Degradation products and pathways have been discerned through the analyses of archaeological finds and the products of laboratory and field-based decay experiments. The origins of preserved fats have been determined through detailed compositional analysis of their component fatty acids by GC, by GC/MS of dimethyl disulfide derivatives of monoenoic components, and by GC-combustion-isotope ratio-MS (GC-C-IRMS), to derive diagenetically robust delta(13)C values. Regiospecific analysis of intact triacylglycerols by high-performance liquid chromatography/MS (HPLC/MS), with atmospheric pressure chemical ionization, provides a further criterion for establishing the origin of fats. Preparative GC has been employed to isolate individual fatty acids from archaeological pottery in sufficient amounts for (14)C dating.  相似文献   
79.
<正>小时候,孩子们的游乐场是房屋与房屋之间狭长的小路,是花园的边缘,是仓库的后巷,是废弃的工房。但当经济大发展将城市土地变得寸土寸金,钢筋水泥的商业森林便开始吞噬孩子们的领地。  相似文献   
80.
High levels of psychological distress in fulltime employees are prevalent (4.5% per month). Symptoms of impaired mental health include difficulties with attention, concentration, motivation, decision-making, visuo-motor control, and psychomotor reaction times. There is limited research on the impact these symptoms have on heavy goods vehicle (HGV) drivers’ performance. In this study 1324 HGV drivers were surveyed using the Depression, Anxiety, Stress Scale (DASS) and the Health and Performance at Work Questionnaire (HPQ). Depression, anxiety and stress had little effect on driver absenteeism rates or self-rated driving performance. However, severe (1.5% of drivers) and very severe (1.8% of drivers) depression was associated with an increased odds ratio (OR = 4.5 and 5.0, respectively) for being involved in an accident or near miss in the past 28 days. This odd ratio is akin to driving with a blood alcohol content of about 0.08%. Given the number of HGV vehicles and the prevalence of depression this equates to 10,950 HGV drivers with an increased statistical risk of an accident or near miss. As the impact of HGV accidents is potentially large, including loss of life, it would be sensible to extend the research findings here into an action plan.  相似文献   
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