Characteristics of origin-destination pair traffic in Funet

In this paper we analyze measurements gathered from a 2.5~Gbps link in the Finnish university network (Funet) in 2004. The traffic is broken down into origin-destination (OD) pair components based on source and destination IP address. We study the traffic characteristics of these components, and identify four typical representative OD pairs. For these pairs we investigate the validity of a moving IID Gaussian model. We find that the statistical properties of these OD pairs differ significantly from each other, with only some of them close to Gaussian. The OD pairs are also found to have some cross-correlation between each other, contradicting an often made assumption about OD pair independence. Furthermore, the existence of a mean-variance relation between the OD pairs is studied. We find that there is a relation between mean and variance, but for some periods of time it is rather weak.     

UVB Radiation Variably Affects n-3 Fatty Acids but Elevated Temperature Reduces n-3 Fatty Acids in Juvenile Atlantic Salmon (Salmo salar)

Temperature and ultraviolet B radiation (UVB 290–320?nm) are inextricably linked to global climate change. These two variables may act separately, additively, or synergistically on specific aspects of fish biochemistry. We raised Atlantic Salmon (Salmo salar) parr for 54?days in outdoor tanks held at 12 and 19?°C and, at each temperature, we exposed them to three spectral treatments differing in UV radiation intensity. We quantified individual fatty acid (FA) mass fractions in four tissues (dorsal muscle, dorsal and ventral skin, and ocular tissue) at each temperature?×?UV combination. FA composition of dorsal muscle and dorsal and ventral skin was not affected by UV exposure. Mass fractions of 16:0, 18:0, and saturated fatty acids (SFA) were greater in dorsal muscle of warm-reared fish whereas 18:3n-3, 20:2, 20:4n-6, 22:5n-3, 22:6n-3, n-3, n-6, polyunsaturated fatty acids (PUFA), and total FA were significantly higher in cold-reared fish. Mass fractions of most of the FA were greater in the dorsal and ventral skin of warm-reared fish. Cold-reared salmon exposed to enhanced UVB had higher ocular tissue mass fractions of 20:2, 20:4n-6, 22:6n-3, n-3, n-6, and PUFA compared to fish in which UV had been removed. These observations forecast a host of ensuing physiological and ecological responses of juvenile Atlantic Salmon to increasing temperatures and UVB levels in native streams and rivers where they mature before smolting and returning to the sea.     

Feasibility of force platform based roadside drowsiness screening – A pilot study

Previous research on driver drowsiness detection has focused on developing in-car systems that continuously monitor the driver while driving and warn him/her when drowsiness compromises safety. In occupational settings a simple test of postural control has showed sensitivity to work shift induced fatigue in drivers. Whether the test is feasible for surveillance purposes in roadside settings is unknown. The present research sought to evaluate the feasibility of using a force platform test of postural control as a breathalyzer-like drowsiness-test at the roadside.     

当地取向下的商业中心——芬兰Easton商业中心

正LAHDELMA MAHLAM?KI ARCHITECTS公司成立于1997,是由长期合作伙伴Ilmari Lahdelma和Rainer Mahlam?KI共同成立的。目前,该办公室由来自芬兰和海外的37位建筑师、设计师和传播者组成。他们的作品展示了芬兰固有的设计:注重可持续性、材料和高质量的细节。这些设计特点结合尖端的技术,将芬兰建筑推向国际舞台。     

Virtual reality in posturography.

Balance dysfunctions are common, especially among elderly people. Present methods for the diagnosis and evaluation of severity of dysfuntion have limited value. We present a system that makes it easy to implement different visual and mechanical perturbations for clinical investigations of balance and visual-vestibular interaction. The system combines virtual reality visual stimulation with force platform posturography on a moving platform. We evaluate our contruction's utility in a classification task between 33 healthy controls and 77 patients with Ménière's disease, using a series of tests with different visual and mechanical stimuli. Responses of patients and controls differ significantly in parameters computed from stabilograms. We also show that the series of tests achieves a classification accuracy slightly over 80% between controls and patients.     

Major depression in the elderly: a population study in Helsinki

The aim of the study was to estimate the prevalence of major depression and to evaluate associated features in random age cohorts of 75, 80, and 85 years (N = 651). A clinical examination was made by experienced health center physicians, and major depression was diagnosed according to DSM-III criteria. The prevalence increased with age and was 1% to 4% in the age groups of 75 and 80 years, but 13% at the age of 85 years. No sex difference was found. The frequency of major depression was fourfold among institutionalized patients (16%) as compared to those living at home (4%). Major depression was strongly associated with objective health, intellectual functioning, and functional capacity. Depression was most common in subjects suffering from poor vision, urinary incontinence, or Parkinson's disease (odd ratios 4.2 to 4.9). Depression was also correlated with musculoskeletal disorders, coronary heart disease, and cerebrovascular diseases (odd ratios 2.5 to 3.4). The survey suggests that major depression is quite rare in healthy elderly people but common in disabled institutionalized patients.     

Unobtrusive stress detection on the basis of smartphone usage data

Stress has become an important health problem, but existing stress detectors are inconvenient in long-term real-life use because users either have to wear dedicated devices or expend notable interaction efforts in system adaptation to specifics of each person. Adaptation is necessary because individuals significantly differ in their perception of stress and stress responses, but typical adaptation employs supervised learning methods and hence requires fairly large sets of labelled data (i.e. information on whether each reporting period was stressful or not) from every user. To address these problems, we propose a novel unsupervised stress detector, based on using a smartphone as the only device and using discrete hidden Markov models (HMM) with maximum posterior marginal (MPM) decisions for analysis of phone data. Our detector requires neither additional hardware nor data labelling and hence is truly unobtrusive and suitable for lifelong use. Its accuracy was evaluated using two real-life datasets: in the first case, adaptation was based on very short (a few days) phone interaction histories of each individual, and in the second case—on longer histories. In these tests, the proposed HMM-MPM achieved 59 and 70% accuracies, respectively, which is comparable with results of fully supervised methods, reported by other works.     

Degradative and mechanical properties of a novel resorbable plating system during a 3-year follow-up in vivo and in vitro

We tested the tissue reactions and mechanical strength of a novel biodegradable craniomaxillofacial plating system, Inion CPS™, in the course of degradation. Plates and screws composed of l-lactide, d-lactide and trimethylene carbonate were implanted to the mandible and dorsal subcutis of 12 sheep. The animals were sacrificed at 6–156 weeks. Histological evaluation was done using paraffin and methylmetacrylate techniques. Degradative and mechanical properties during the follow-up were measured both of in vivo and in vitro implants. In light microscopy, the in vivo implant material began to fragment at 52 weeks and could not be detected at 104 weeks. No significant foreign body reactions were seen in the mandibles. The dorsal subcutis disclosed mild reactions, which were, however, not of clinical significance. The implants in vitro maintained their entire mass for 26 weeks and lost 63–80% of the mass by week 104. The inherent viscosity of the implants in vitro and in vivo diminished uniformly. The screws retained their shear strength for 12–16 weeks. The plates maintained their tensile strength for at least 6 weeks. The maximum capacity of the plates in 3-point bending tests diminished gradually by 87% in 26 weeks. In conclusion, the plates and screws examined maintain adequate strength for the healing period of a bone fracture or osteotomy, producing no harmful foreign body reactions. Dr Nieminen is a consultant for Inion Ltd., while the other co-authors do not have any conflicts of interest. Inion Ltd. has financed the costs related to the study sheep, including their housing.