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Factors Determining Competitiveness in Healthcare Institutions in Latvia – Results of the EKOSOC-LV National Research Programme

Abstract

Competitiveness as a factor of a company selling its services in the market is becoming more relevant in the healthcare sector. The number of institutions that offer their services to international patients is growing. Research shows that the development of medical tourism is country-specific. The main objective of this publication is to discover positive and negative factors for engagement in the provision of services to non-residents. The data was obtained from a cross-sectional study in which 86 managers of health care institutions in Latvia completed a questionnaire. A total of 80.2% of health care institutions had provided services to non-resident patients in the previous year while 19.8% did so regularly. Institutions mainly used websites to advertise their services. Only a small number of institutions employed a marketing specialist or had a strategy to attract non-resident patients. Heads of institutions pointed to a number of internal and external barriers in this connection, including lack of staff, low motivation, limited language skills, inadequate infrastructure, insufficient state-level support to promote the export of services, the social environment, and problems in the health system itself. The study revealed areas that need to be improved regarding future policies to attract non-resident patients and to increase global competitiveness.

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Fractional natural decomposition method for solving a certain class of nonlinear time-fractional wave-like equations with variable coefficients

Abstract

In this paper, we propose a new approximate method, namely fractional natural decomposition method (FNDM) in order to solve a certain class of nonlinear time-fractional wave-like equations with variable coefficients. The fractional natural decomposition method is a combined form of the natural transform method and the Adomian decomposition method. The nonlinear term can easily be handled with the help of Adomian polynomials which is considered to be a clear advantage of this technique over the decomposition method. Some examples are given to illustrate the applicability and the easiness of this approach.

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gr-n-ideals in graded commutative rings

Abstract

Let G be a group with identity e and let R be a G-graded ring. In this paper, we introduce and study the concept of gr-n-ideals of R. We obtain many results concerning gr-n-ideals. Some characterizations of gr-n-ideals and their homogeneous components are given.

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Harmonic univalent functions defined by post quantum calculus operators

Abstract

We study a family of harmonic univalent functions in the open unit disc defined by using post quantum calculus operators. We first obtained a coefficient characterization of these functions. Using this, coefficients estimates, distortion and covering theorems were also obtained. The extreme points of the family and a radius result were also obtained. The results obtained include several known results as special cases.

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How Many Weak-Keys Exist in T-310 ?

Abstract

T-310 is an important Cold War cipher. The cipher is extremely complex and it outputs extremely few bits from the internal state. A recent paper [Courtois, N. T.: Decryption oracle slide attacks on T-310, Cryptologia, 42 (2018), no. 3, 191–204] shows an example of a highly anomalous key such that T-310 can be broken by a slide attack with a decryption oracle. In this paper, we show that the same attacks are ALSO possible for regular keys which satisfy all the official KT1 requirements. Two other recent papers [Courtois, N. T.—Georgiou, M.—Scarlata, M.: Slide attacks and LC-weak keys in T-310, Cryptologia 43 (2019), no. 3, 175–189]; [Courtois, N. T.—Oprisanu, M. B.—Schmeh, K.: Linear cryptanalysis and block cipher design in East Germany in the 1970s, Cryptologia (published online), December 5, 2018] show that some of the KT1 keys are very weak w.r.t. Linear Cryptanalysis. In this paper, we show that a vast number of such weak keys exist and study the exact pre-conditions which make them weak. In addition we introduce a new third class of weak keys for RKDC (Related-Key Differential Cryptanalysis). We show that the original designers in the 1970s have ensured that these RKDC properties cannot happen for 4 rounds. We have discovered that these properties can happen for as few as 5 rounds for some keys, and for 10 to 16 rounds they become hard to avoid. The main reason why we study weak keys is to show that none of these properties occur by accident, rather that they are governed by precise pre-conditions which guarantee their existence, and countless other keys with the same properties exist. Eventually, this is how interesting attacks can be found.

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I-Rad-⊕-supplemented modules

Abstract

Let M be an R-module and I be an ideal of R. We say that M is I-Rad-⊕-supplemented, provided for every submodule N of M, there exists a direct summand K of M such that M = N + K, N ∩ K ⊆ IK and N ∩ K Rad(K). The aim of this paper is to show new properties of I-Rad-⊕-supplemented modules. Especially, we show that any finite direct sum of I-Rad-⊕-supplemented modules is I-Rad-⊕-supplemented. We also prove that an R-module M is I-Rad-⊕-supplemented if and only if K and MK are I-Rad-⊕-supplemented for a fully invariant direct summand K of M. Finally, we determine the structure of I-Rad-⊕-supplemented modules over a discrete valuation ring.

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Incidence of Permanent Pacemaker Implantation after Cardiac Surgery: A Single Centre Experience

Abstract

Permanent pacemaker implantation (PPI) after open heart surgery is required in 0.4–8.5% of patients. The aim of our study was to determine the incidence of PPI after cardiac surgery at Pauls Stradiņš Clinical University Hospital and to assess its influence on intrahospital outcomes. This was a single-centre retrospective study. We reviewed all patients who underwent either open heart surgery or transcatheter aortic valve implantation (TAVI) between the years 2015 and 2017. Included were all patients with PPI postoperatively before discharge. We compared the patient demographics, and perioperative state, incidence of PPI and intrahospital stay among groups. After cardiac surgery a total of 135 (4.2%) patients received a PPI. The PPI incidence was highest in the tricuspid valve intervention group — 8.8% followed by aortic valve replacement (AVR) patients with 3.3%. After TAVI incidence of PPI was 4.0% after Sapien valve and 8% after CoreValve implantations, respectively. Incidence of PPI after TAVI with the Sapien valve was not significantly higher when compared to conventional AVR, but it was significantly higher after TAVI with CoreValve. Regardless of the initial procedure a need for PPI significantly increased the total length of hospital stay.

Open access
Incremental Role of Pathological Personality Traits in the Prediction of Suicidal Ideation in General and Psychiatric Inpatient Sample

Abstract

The aim of this study was to evaluate the utility of the pathological personality traits in predicting suicidal ideation, especially in combination with other risk factors, such as the level of depression, prior attempts of suicide, low self-esteem, low level of perceived social support and self-esteem-by-social support interaction, both in general and in psychiatric inpatient samples. Data were analysed within two samples: non-clinical general sample (n = 461) and psychiatric inpatient sample (n = 131). Latvian Clinical Personality Inventory (LCPI) was used as the instrument for data collection. LCPI is a comprehensive multi-scale multi-item inventory, which consists of nine clinical scales (including Depression Symptom Scale), 33 pathological personality scales, five functioning scales, and five additional scales, including a Suicidal Ideation Scale, Low Self-esteem Scale and Lack of Perceived Social Support Scale. Results of the hierarchical regression analysis showed that several facet-level pathological personality traits (depressivity, self-harm, dissociation proneness, submissiveness, and suspiciousness) added significant incremental variance to the prediction of suicidal ideation above and beyond the well-known main risk factors of suicidal ideation, such as depression and prior suicide attempt. This effect remained stable even after taking into account additional interpersonal risk factors, such as low self-esteem, low level of perceived social support and self-esteem-by-perceived social support interaction. The incremental effect of personality traits was medium in the psychiatric inpatient sample and small in the general sample. Findings of the study may assist in early screening for persons with suicide risk and for developing prevention programmes in different settings.

Open access
Initial coefficient bounds for certain class of meromorphic bi-univalent functions

Abstract

In this paper, we introduce and investigate an interesting subclass of meromorphic bi-univalent functions defined on Δ = {z ∈ ℂ: 1 < |z| < ∞}. For functions belonging to this class, estimates on the initial coefficients are obtained. The results presented in this paper generalize and improve some recent works.

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Laboratory Tests in Addition to the Alvarado Score in the Management of Acute Appendicitis in School-Age Children

Abstract

The aim of the study was to determine whether the Alvarado score (AS) together with laboratory tests could be used to distinguish patients with acute appendicitis (AA) from acute mesenteric lymphadenitis (AML). Fifty-seven patients (7–18 years) with suspected AA were included in the prospective study (October 2010 – October 2013). Thirty-one patients underwent surgery for AA and 26 were not treated surgically and were diagnosed AML on ultrasonography. AS, white blood cell count (WBC), C – reactive protein (CRP) and serum cytokines (EGF, IL-10, IL-12(p70), IL-1β, IL-4, IL-6, IL-8, IL-17, MCP-1, TNF-α) were obtained on admission and were compared between groups. Mean age of the 57 patients was 12.9 (SD 3.2). Accuracy (AR) for AS ≥ 7 alone was 73.7% for AA. Modified AS with certain serum cytokines seemed to be a reliable tool for initial differential diagnosis between AA and AML in school-age children. Based on these results, AS ≥ 7, WBC ≥ 10.7 × 103/µL and serum IL-6 ≥ 4.3 pg/mL assessed altogether will yield more sensitivity for AA. Also for further advanced diagnostics, we propose to take into account the serum IL-6, IL-8, MCP-1, CRP cut-off levels in the differential diagnosis between complicated and uncomplicated AA to decide whether the treatment should be conservative or surgical.

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