Average-Case Optimal Approximate Circular String Matching

Approximate string matching is the problem of finding all factors of a text t of length n that are at a distance at most k from a pattern x of length m. Approximate circular string matching is the problem of finding all factors of t that are at a distance at most k from x or from any of its rotations. In this article, we present a new algorithm for approximate circular string matching under the edit distance model with optimal average-case search time O(n(k + log m)/m). Optimal average-case search time can also be achieved by the algorithms for multiple approximate string matching (Fredriksson and Navarro, 2004) using x and its rotations as the set of multiple patterns. Here we reduce the preprocessing time and space requirements compared to that approach

Biotelemetric Wireless Intracranial Pressure Monitoring: An In Vitro

Assessment of intracranial pressure (ICP) is of great importance in management of traumatic brain injuries (TBIs). The existing clinically established ICP measurement methods require catheter insertion in the cranial cavity. This increases the risk of infection and hemorrhage. Thus, noninvasive but accurate techniques are attractive. In this paper, we present two wireless, batteryless, and minimally invasive implantable sensors for continuous ICP monitoring. The implants comprise ultrathin (50 μm) flexible spiral coils connected in parallel to a capacitive microelectromechanical systems (MEMS) pressure sensor. The implantable sensors are inductively coupled to an external on-body reader antenna. The ICP variation can be detected wirelessly through measuring the reader antenna’s input impedance. This paper also proposes novel implant placement to improve the efficiency of the inductive link. In this study, the performance of the proposed telemetry system was evaluated in a hydrostatic pressure measurement setup. The impact of the human tissues on the inductive link was simulated using a 5 mm layer of pig skin. The results from the in vitro measurement proved the capability of our developed sensors to detect ICP variations ranging from 0 to 70 mmHg at 2.5 mmHg intervals

Faster Approximate String Matching for Short Patterns

We study the classical approximate string matching problem, that is, given strings $P$ and $Q$ and an error threshold $k$, find all ending positions of substrings of $Q$ whose edit distance to $P$ is at most $k$. Let $P$ and $Q$ have lengths $m$ and $n$, respectively. On a standard unit-cost word RAM with word size $w \geq \log n$ we present an algorithm using time $$O(nk \cdot \min(\frac{\log^2 m}{\log n},\frac{\log^2 m\log w}{w}) + n)$$ When $P$ is short, namely, $m = 2^{o(\sqrt{\log n})}$ or $m = 2^{o(\sqrt{w/\log w})}$ this improves the previously best known time bounds for the problem. The result is achieved using a novel implementation of the Landau-Vishkin algorithm based on tabulation and word-level parallelism.Comment: To appear in Theory of Computing System

Real-world clinical diagnostics of heart failure patients with reduced or preserved ejection fraction

Aims The study aimed at investigating the use of guideline-recommended diagnostic tools and medication in patients with heart failure (HF) in specialty care in Southwest Finland. We also compared the characteristics of the diagnosed and undiagnosed patients as well as laboratory tests, procedures, and treatments in everyday clinical practice.Methods and results Patients diagnosed with HF, cardiomyopathy, or hypertension-induced heart disease (n = 20 878, primary cohort) or not diagnosed with HF but having a record of elevated N-terminal pro-brain natriuretic peptide (NT-proBNP) (>125 ng/L, n = 24 321, secondary cohort) were included in the study from the specialty care patient register of the Hospital District of Southwest Finland during the years 2005-2017. Among patients with an International Classification of Diseases, Tenth Revision (ICD-10) code for HF, only 50% had ejection fraction (EF) data to be found by data mining from the electronic health records. Of these patients, 39% (n = 4042) had EF 40%. Elevated NT-proBNP together with EF > 40% narrowed down the number to 4590 patients, a population defined as HF with preserved EF (HFpEF) patients. HFpEF patients were further stratified into HF with mildly reduced EF (HFmrEF; EF 41-50%, n = 1468) and EF > 50% patients (n = 3122) to compare clinical characteristics. NT-proBNP was higher within the HFrEF patients vs. HFpEF {4580 [inter-quartile range (IQR): 2065-9765] vs. 2900 [2065-9765] ng/L, P 50% patients. In 70% (n = 17 156) of patients in the secondary cohort, the NT-proBNP concentrations were >300 ng/L, median was 1090 (IQR 551-2558) ng/L and EF 58.4 +/- 12.1% (n with EF available = 6845). Reduced EF was present in 6.8% of patients lacking HF diagnosis.Conclusions Half of the patients with ICD-10 code for HF did not have EF data available after a visit at specialty care. In particular, the diagnosis of HFpEF seems challenging, reflected as an increase in procedures and laboratory test preceding diagnosis compared with those in HFrEF patients. Also, a large proportion of patients did not have HF diagnosis, yet they presented elevated NT-proBNP concentrations and clinical characteristics resembling those of HFpEF patients

Wireless Dopamine sensing brain implant: The concept and first results

acceptedVersionPeer reviewe

Antennas and wireless power transfer to small biomedical brain implants

Peer reviewe

Wireless brain implant for Dopamine monitoring

acceptedVersionPeer reviewe