32 research outputs found
Variability of the ice area and the possibility of achieving an ice-free regime in the Barents Sea
The results of the analysis of the interannual variability of the Barents Sea ice area, including trends in the area of sea ice distribution for the period 1979-2018 based on remote sensing data, are presented. The analysis of trends is based on a dimensionless trend index, which allows comparing different areas of sea ice distribution. Estimates of the Barents Sea ice-free regime in January and August are presented on the basis of extrapolation of trends for the period 1979-2018. The ice-free regime of the Barents Sea in January is expected in 2055, in August - 2026
Investment activity and environmental protection: Balancing investors’ interests and environmental challenges
At present, the issue of environmental pollution is gradually becoming one of the central problems facing individual countries and the international community. Meanwhile, the analysis of investment projects shows that most of them are focused on profit making, without due consideration of public environmental interests. In this regard, there is a serious need to find a balance between the interests of investors and the interests of society and citizens in preserving and improving the natural environment. In such circumstances, the state environmental policy should be based on an optimal combination of both administrative methods of influencing investors (penalties, environmental taxes, compensation for environmental damage) and the promotion of so-called environmental investment which implies the development and implementation of a specific investment project, whose goal will be to solve a specific environmental problem. The authors identify various legal forms of environmentally oriented investment, as well as formulate proposals for improving the current legislation in this area
DESCRIPTION OF GAS HYDRATES EQUILIBRIA IN SEDIMENTS USING EXPERIMENTAL DATA OF SOIL WATER POTENTIAL
The purpose of the work is to show how to employ the experimental data from geocryology and soil physics for thermodynamic calculations of gas hydrate phase equilibria by taking into account pore water behavior in sediments. In fact, thermodynamic calculation is used here to determine the amount of non-clathrated pore water content in sediments in equilibrium with gas and hydrate phases.
A thermodynamic model for pore water behavior in sediments is developed. Taking into account the experimental water potential data, the model calculations show good agreement with the experimentally measured unfrozen water content for different pressure and temperature conditions. The proposed thermodynamic model is applied for calculations of three-phase equilibria: multicomponent gas phase (methane, natural gas, etc.) – pore water in clay, sand, loamy sand, etc. – bulk (or pore) hydrate. As a result, correlations have been established between unfrozen and non-clathrated water content in natural sediments.Non UBCUnreviewe
Variability of the ice area and the possibility of achieving an ice-free regime in the Barents Sea
The results of the analysis of the interannual variability of the Barents Sea ice area, including trends in the area of sea ice distribution for the period 1979-2018 based on remote sensing data, are presented. The analysis of trends is based on a dimensionless trend index, which allows comparing different areas of sea ice distribution. Estimates of the Barents Sea ice-free regime in January and August are presented on the basis of extrapolation of trends for the period 1979-2018. The ice-free regime of the Barents Sea in January is expected in 2055, in August - 2026
Pneumococcal Meningitis in Adults after Introduction of PCV7 and PCV13, Israel, July 2009–June 2015
The indirect effect of pneumococcal conjugate vaccine on adult pneumococcal meningitis has not been thoroughly investigated. We present data from active surveillance on pneumococcal meningitis in adults in Israel occurring during July 2009–June 2015. Pneumococcal meningitis was diagnosed for 221 patients, 9.4% of all invasive pneumococcal disease (IPD) cases. Although overall IPD incidence decreased during the study period, meningitis increased nonsignificantly from 0.66 to 0.85 cases/100,000 population. Incidence of vaccine type (VT) pneumococcal meningitis (VT13) decreased by 70%, but non-VT13 pneumococcal meningitis increased from 0.32 to 0.75 cases/100,000 population (incident rate ratio 2.35, 95% CI 1.27–4.35). Pneumococcal meningitis patients were younger and healthier than nonmeningitis IPD patients, and 20.2% had a history of previous head surgery or cerebrospinal fluid leak compared with <2.0% of nonmeningitis patients (p<0.0001). Non-VT13 types that rarely cause IPD (15B/C, 6C, 23A, 23B, 24F) seem to be emerging as common causes of meningitis
Mutation D30N Is Not Preferentially Selected by Human Immunodeficiency Virus Type 1 Subtype C in the Development of Resistance to Nelfinavir
Differences in baseline polymorphisms between subtypes may result in development of diverse mutational pathways during antiretroviral treatment. We compared drug resistance in patients with human immunodeficiency virus subtype C (referred to herein as “subtype-C-infected patients”) versus subtype-B-infected patients following protease inhibitor (PI) therapy. Genotype, phenotype, and replication capacity (Phenosense; Virologic) were determined. We evaluated 159 subtype-C- and 65 subtype-B-infected patients failing first PI treatment. Following nelfinavir treatment, the unique nelfinavir mutation D30N was substantially less frequent in C (7%) than in B (23%; P = 0.03) while L90M was similar (P < 0.5). Significant differences were found in the rates of M36I (98 and 36%), L63P (35 and 59%), A71V (3 and 32%), V77I (0 and 36%), and I93L (91 and 32%) (0.0001 < P < 0.05) in C and B, respectively. Other mutations were L10I/V, K20R, M46I, V82A/I, I84V, N88D, and N88S. Subtype C samples with mutation D30N showed a 50% inhibitory concentration (IC(50)) change in susceptibility to nelfinavir only. Other mutations increased IC(50) correlates to all PIs. Following accumulation of mutations, replication capacity of the C virus was reduced from 43% ± 22% to 22% ± 15% (P = 0.04). We confirmed the selective nature of the D30N mutation in C, and the broader cross-resistance of other common protease inhibitor mutations. The rates at which these mutational pathways develop differ in C and subtype-B-infected patients failing therapy, possibly due to the differential impact of baseline polymorphisms. Because mutation D30N is not preferentially selected in nelfinavir-treated subtype-C-infected patients, as it is in those infected with subtype B, the consideration of using this drug initially to preserve future protease inhibitor options is less relevant for subtype-C-infected patients
Transmission patterns of HIV-subtypes A/AE versus B: inferring risk-behavior trends and treatment-efficacy limitations from viral genotypic data obtained prior to and during antiretroviral therapy.
BACKGROUND: HIV subtypes A and CRF01_AE (A/AE) became prevalent in Israel, first through immigration of infected people, mostly intravenous-drug users (IVDU), from Former Soviet-Union (FSU) countries and then also by local spreading. We retrospectively studied virus-transmission patterns of these subtypes in comparison to the longer-established subtype B, evaluating in particular risk-group related differences. We also examined to what extent distinct drug-resistance patterns in subtypes A/AE versus B reflected differences in patient behavior and drug-treatment history. METHODS: Reverse-transcriptase (RT) and protease sequences were retrospectively analyzed along with clinical and epidemiological data. MEGA, ClusalX, and Beast programs were used in a phylogenetic analysis to identify transmission networks. RESULTS: 318 drug-naive individuals with A/AE or patients failing combination antiretroviral therapy (cART) were identified. 61% were IVDU. Compared to infected homosexuals, IVDU transmitted HIV infrequently and, typically, only to a single partner. 6.8% of drug-naive patients had drug resistance. Treatment-failing, regimen-stratified subtype-A/AE- and B-patients differed from each other significantly in the frequencies of the major resistance-conferring mutations T215FY, K219QE and several secondary mutations. Notably, failing boosted protease-inhibitors (PI) treatment was not significantly associated with protease or RT mutations in either subtype. CONCLUSIONS: While sizable transmission networks occur in infected homosexuals, continued HIV transmission among IVDU in Israel is largely sporadic and the rate is relatively modest, as is that of drug-resistance transmission. Deviation of drug-naive A/AE sequences from subtype-B consensus sequence, documented here, may subtly affect drug-resistance pathways. Conspicuous differences in overall drug-resistance that are manifest before regimen stratification can be largely explained in terms of treatment history, by the different efficacy/adherence limitations of older versus newer regimens. The phenomenon of treatment failure in boosted-PI-including regimens in the apparent absence of drug-resistance to any of the drugs, and its relation to adherence, require further investigation
Comparable long-term efficacy of Lopinavir/Ritonavir and similar drug-resistance profiles in different HIV-1 subtypes.
BACKGROUND: Analysis of potentially different impact of Lopinavir/Ritonavir (LPV/r) on non-B subtypes is confounded by dissimilarities in the conditions existing in different countries. We retrospectively compared its impact on populations infected with subtypes B and C in Israel, where patients infected with different subtypes receive the same treatment. METHODS: Clinical and demographic data were reported by physicians. Resistance was tested after treatment failure. Statistical analyses were conducted using SPSS. RESULTS: 607 LPV/r treated patients (365 male) were included. 139 had HIV subtype B, 391 C, and 77 other subtypes. At study end 429 (71%) were receiving LPV/r. No significant differences in PI treatment history and in median viral-load (VL) at treatment initiation and termination existed between subtypes. MSM discontinued LPV/r more often than others even when the virologic outcome was good (p = 0.001). VL was below detection level in 81% of patients for whom LPV/r was first PI and in 67% when it was second (P = 0.001). Median VL decrease from baseline was 1.9±0.1 logs and was not significantly associated with subtype. Median CD4 increase was: 162 and 92cells/µl, respectively, for patients receiving LPV/r as first and second PI (P = 0.001), and 175 and 98, respectively, for subtypes B and C (P<0.001). Only 52 (22%) of 237 patients genotyped while under LPV/r were fully resistant to the drug; 12(5%) were partially resistant. In48%, population sequencing did not reveal resistance to any drug notwithstanding the virologic failure. No difference was found in the rates of resistance development between B and C (p = 0.16). CONCLUSIONS: Treatment with LPV/r appeared efficient and tolerable in both subtypes, B and C, but CD4 recovery was significantly better in virologically suppressed subtype-B patients. In both subtypes, LPV/r was more beneficial when given as first PI. Mostly, reasons other than resistance development caused discontinuation of treatment
Mutations found in patients failing regiments containing LPV/r or NNRTIs.
<p>Mutations found in patients failing regiments containing LPV/r or NNRTIs.</p><p>The Table classifies patients failing on LPV/r or NNRTI containing regimens according to the number of mutations conferring resistance to the different drug classes. “+” indicates presence of mutations, but for some patients the actual mutations are listed. “–” indicates “no mutations” or also “no previous PI-containing regimens”.</p><p>EFV – efavirenz; IDV – indinavir; LPV/r – lopinovir/ritonavir; NFV – nelfinavir; NNRTIs – Non-nucleosides reverse transcriptase inhibitors; NRTIs – Nucleosides reverse transcriptase inhibitors; NVP – nevirapine; SQV – saquinavir; PIs – protease inhibitors.</p
First-administrated and actual drug regimens while failing treatment.
a<p>All except 5 received NRTIs as part of the first regimen. A few received mono- or duo-therapy or combinations of PIs and NNRTIs.</p>b<p>All 78 treatment-failing patients received NRTI backbone. Thirty-four received also PI and 39 NNRTI as additional drug.</p><p>3TC – lamivudine; EFV – efavirenz; FTC – emtricitabine; LPV/r – lopinavir/r; NNRTI – Non-Nucleoside Reverse Trancriptase Inhibitor; NRTI – Nucleoside Reverse Trancriptase Inhibitor; NVP – nevirapine; PI – Protease inhibitor; r – ritonavir; TDF – tenofovir; ZDV – zidovudine.</p