275 research outputs found
Pulmonary Rehabilitation and Exercise in Pulmonary Arterial Hypertension: An Underutilized Intervention
Pulmonary arterial hypertension (PAH) is a rare and devastating disease characterized by progressive increases in pulmonary arterial pressure and pulmonary vascular resistance which eventually leads to right ventricular failure and death. Early thought process was that exercise and increased physical activity may be detrimental to PAH patients however many small cohort trials have proven otherwise. In addition to the many pharmaceutical options, exercise and pulmonary rehabilitation have also been shown to increase exercise capacity as well as various aspects of psychosomatic health. As pulmonary and exercise rehabilitation become more widely used as an adjuvant therapy patient outcomes improve and physicians should consider this in the therapeutic algorithm along with pharmacotherapy
Influence of different organic resources on crop yield and soil fertility in the Moldavian Plateau
Investigations conducted during 2003-2007 at the Podu-Iloaiei Agricultural
Research Station have studied the influence of different sewage sludge, manure and crop
residues on yield quality and quantity and soil agrochemical characteristics. Experiments were
set up in a five year-crop rotation (soybean-wheat-maize-sunflower-wheat). Sewage sludge
was applied annually at rates of 20, 40 and 60 t/ha, together with mineral fertilizer,
differentiated according to the growing plant. The Cambic Chernozem used for experiments
had a clayey-loam texture (415 g clay, 305 g loam and 280 g sand), a weakly acid reaction
and a mean supply with mobile phosphorus and a very good one with mobile potassium.
Applying rates of 24.6 t/ha DM sewage sludge resulted in the accumulation of mobile
phosphate stock in soil of 49 ppm and the microelements content (mobile forms from soil) was
of 12.4 ppm at Cu, 0.47 ppm at B, 142 ppm at Zn and 382 ppm at manganese. The combined
use of mean rates of mineral fertilizers (N70P70), together with 40 t/ha manure or 6 t/ha crop
residues from wheat and maize crops, has resulted in improving soil physical and chemical
characteristics and getting yield increases in wheat of 2313-2214 kg/ha (136-130 %), on
weakly eroded lands, and 2074-2001 kg/ha (178-172 %) on highly eroded lands, compared to
the unfertilized control. Both on weakly and highly eroded lands, the mineral fertilization with
lower rates than N140P100 kg/ha has determined the decrease in humus content from soil until
2.49- 3.05 %. On highly eroded lands, the humus content was kept at values of 3.42-3.49%
only by the annual application of the rate of 60 t/ha manure or N70P70+ 60 t/ha manure
Effects of long-term fertilization on the fertility of erosion-affected soils from the Moldavian Plateau
The paper presented the results of investigations concerning the influence of
long-term fertilization (43 years) on some chemical characteristics of Cambic Chernozem from
the Moldavian Plain and on the maize yield. On slope lands, the high rate fertilization of maize
crop (N140P100) has determined, in the latest ten years, an average yield increase of 103%
(3373 kg/ha), against the control, and applying a rate of N70P70+40 t/ha manure resulted in
getting a very close yield increase (99%, 3258 kg/ha). The minimum supply level of mobile
phosphorus in soil (37-72 ppm) in pea-wheat-maize rotation (37 ppm) was maintained in case
of annual application of a rate of N100P80. The total carbon content in Cambic Chernozem from
the Moldavian Plain has registered significant increases at higher rates than N140P100 and in
case of organo-mineral fertilization. The annual fertilization of wheat and maize, at the rate of
70 kg N + 70 kg P2O5/ha + 6 t/ha stalks of wheat, has determined, compared to the unfertilized
variant, the increase in the content of organic carbon from soil by 14.5% (2.4 g organic C/kg)
on weakly eroded soils, and by 29.5% (4.2 g organic C/kg) on highly eroded soils. During the
long-term fertilizing of wheat and maize with high rates of mineral fertilizers (N140P100), on
highly eroded lands, the total content of carbon has increased by 16.9% (2.4 g organic C/kg
soil), against the unfertilized control. Applying moderate rates of mineral fertilizers (N70P70),
together with 60 t/ha manure, has determined, after 43 years of testing, the increase by 32%
(5.3 g organic C/kg) in the content of organic carbon from soil, on weakly eroded soils, and by
42.3% (6.0 g organic C/kg soil) on highly eroded soils, compared to the unfertilized control.
On 16% slope arable lands from the Moldavian Plateau, the mean annual soil losses by
erosion, registered during 1986-2007, were of 1.640 t/ha in winter wheat, 4.618 t/ha in beans, 1.89 t/ha in the field cultivated with perennial grasses and legumes on the second year
of vegetation, 9.176 t/ha in maize and 9.6 t/ha in sunflower
The change of physical and chemical characteristics in cambic chernozem, as influenced by soil erosion, in the Moldavian Plain
The analyses carried out on soil profiles, at the beginning of testing period and
after 36 years, on a 16% slope, with length of 310 m, have shown that on the entire slope
length, soils had a very different fertility. Soils were influenced by erosion and silting
processes. On weakly eroded land, the percentage of hydrostable aggregates was comprised,
according to rates and type of applied fertilizers, between 38.9 and 53.6 %; on highly eroded
land, the ratio of hydrostable aggregates has increased from 34.4 in unfertilized control to
52.0% at the fertilized variant with 40 t/ha manure. On eroded slope lands, poor in organic
matter and nutritive elements, applying rates of 40 t/ha manure has determined yield increases
in maize of 1835-2340 kg/ha, respectively, 45.9 – 58.5 kg grains/ t of manure, compared to
unfertilized control. The combined use of mean rates (N70P70) of mineral fertilizers, together
with 40 t/ha manure, has improved soil physical and chemical characteristics. Yield increases
were of 3150 kg/ha in wheat and 3771 kg/ha in maize, compared to unfertilized variant
Effects of temperature and doxorubicin exposure on keratinocyte damage in vitro
Cancer chemotherapy treatment often leads to hair loss, which may be prevented by cooling the scalp during drug administration. The current hypothesis for the hair preservative effect of scalp cooling is that cooling of the scalp skin reduces blood flow (perfusion) and chemical reaction rates. Reduced perfusion leads to less drugs available for uptake, whereas the reduced temperature decreases uptake of and damage by chemotherapy. Altogether, less damage is exerted to the hair cells, and the hair is preserved. However, the two mechanisms in the hypothesis have not been quantified yet. To quantify the effect of reduced drug damage caused by falling temperatures, we investigated the effect of local drug concentration and local tissue temperature on hair cell damage using in vitro experiments on keratinocytes. Cells were exposed for 4 h to a wide range of doxorubicin concentrations. During exposure, cells were kept at different temperatures. Cell viability was determined after 3 d using a viability test. Control samples were used to establish a concentration–viability curve. Results show that cell survival is significantly higher in cooled cells (T < 22° C) than in non-cooled cells (T = 37° C), but no significant differences are visible between T = 10° C and T = 22° C. Based on this result and previous work, we can conclude that there is an optimal temperature in scalp cooling. Further cooling will only result in unnecessary discomfort for the patient and should therefore be avoided
Paging on Complex Architectures
Advances in technology allow to build computer systems of ever increasing performances and capabilities. However, the effective use of such computational resources is often made difficult by the complexity of the system itself. Crucial to the performance of a computing device is the orchestration of the flow of data across the memory hierarchy. Specifically, given a fast but small memory (a cache) through which all the data that have to be processed must pass, it is necessary to establish a set of rules, then implemented by an algorithm, that define which data has to be evicted from such a memory to make room for new incoming data. The goal is that of minimizing the number of times that requested data is outside the cache (faults), since fetching data from farther levels of the memory hierarchy incurs high costs, in terms of time and also of energy. This thesis studies two generalizations of this problem, known as the paging problem. This problem is intrinsically online, as future data requests issued by a computer program are typically unknown.
Motivated by the recent diffusion of multi-threaded and multi-core
architectures, whereby several threads or processes can be executed
simultaneously, and/or there are several processing units, and by the recent and rapidly growing interest in reducing power consumptions of computer systems, in the first part of the thesis we study a variation of paging which rewards the efficient usage of memory resources. In this problem the goal is that of minimizing a combination of both the number of faults and the cache occupancy of the process' data in fast memory. The main results of this part are two: the first is an impossibility result that indicates that, roughly speaking, online algorithms cannot compete in practice with algorithms that know
in advance all the data requests issued by the process; the second is the design of an online algorithm that has almost the best performance among all the possible online algorithms.
In the second part of the thesis we concentrate on the management of a cache shared among several concurrent processes. As outlined above, this has direct application in multi-threaded or multi-core architectures. In this problem the fast memory has to service a sequence of requests which is the interleaving of the requests issued by t different processes. Through its replacement decisions, the algorithm dynamically allocates the cache space among the processes, and this clearly impacts their progress. The main goal here is to minimize the time needed to complete the service of all the request sequences. We show tight lower and upper bounds on the performance of online algorithms for several variants of the problem
Repeated out-of-Africa expansions of Helicobacter pylori driven by replacement of deleterious mutations
Erratum in: Nat Commun. 2023 Mar 20;14(1):1539. doi: 10.1038/s41467-023-37302-5.Helicobacter pylori lives in the human stomach and has a population structure
resembling that of its host. However, H. pylori fromEurope and the Middle East
trace substantially more ancestry from modern African populations than the
humans that carry them. Here, we use a collection of Afro-Eurasian H. pylori
genomes to show that this African ancestry is due to at least three distinct
admixture events. H. pylori from East Asia, which have undergone little
admixture, have accumulated many more non-synonymous mutations than
African strains. European and Middle Eastern bacteria have elevated African
ancestry at the sites of these mutations, implying selection to remove them
during admixture. Simulations show that population fitness can be restored
after bottlenecks bymigration and subsequent admixture of small numbers of
bacteria from non-bottlenecked populations. We conclude that recent spread
of African DNA has been driven by deleterious mutations accumulated during
the original out-of-Africa bottleneck.This work
was supported by Sequencing Grants-in-aid for Scientific Research from
the Ministry of Education, Culture, Sports, Science, and Technology
(MEXT) of Japan (221S0002, 18KK0266, 19H03473, 21H00346 and
22H02871) to Y.Y. F.F.V. is financed by FCT through Assistant Researcher
grant CEECIND/03023/2017 and a project grant PTDC/BTM-TEC/3238/
2020. I.K. studentship was funded by the National Strategic Reference
Framework Operational Program “Competitiveness, Entrepreneurship
and Innovation” (NSRF 2014-2020, project No. MIS5002486) and
sequencing of strains was supported by the InfeNeutra Project (NSRF
2007-2013, project no. MIS450598) of the Ministry of Culture and Edu-
cation, Greece. K.T. and the sequencing of KI isolates was supported by
Erik Philip-Sörensen Foundation grant G2016-08, and Swedish Society
for Medical research (SSMF). All primary bioinformatics and parts of the
comparative genomics were performed on resources provided by
Swedish National Infrastructure for Computing (SNIC) through Uppsala
Multidisciplinary Center for Advanced Computational Science
(UPPMAX) under projects snic2018-8-24 and uppstore2017270. Work by
S.S. was supported by the German Research Foundation (DFG, project
number 158 989 968–SFB 900/A1) and by the Bavarian Ministry of Sci-
ence and the Arts in the framework of the Bavarian Research Network
“New Strategies Against Multi-Resistant Pathogens by Means of Digital
Networking—bayresq.net”. D.F. was supported by Shanghai Municipal
Science and Technology Major Project No. 2019SHZDZX02.info:eu-repo/semantics/publishedVersio
A Characterisation of Smart Grid DoS Attacks
Traditional power grids are evolving to keep pace with the demands of the modern age. Smart grids contain integrated IT systems for better management and efficiency, but in doing so, also inherit a plethora of cyber-security threats and vulnerabilities. Denial-of-Service (DoS) is one such threat. At the same time, the smart grid has particular characteristics (e.g. minimal delay tolerance), which can influence the nature of threats and so require special consideration. In this paper, we identify a set of possible smart grid-specific DoS scenarios based on current research, and analyse them in the context of the grid components they target. Based on this, we propose a novel target-based classification scheme and further characterise each scenario by qualitatively exploring it in the context of the underlying grid infrastructure. This culminates in a smart grid-centric analysis of the threat to reveal the nature of DoS in this environment
SARS-CoV-2 Molecular Transmission Clusters and Containment Measures in Ten European Regions during the First Pandemic Wave
International audienceBackground: The spatiotemporal profiling of molecular transmission clusters (MTCs) using viral genomic data can effectively identify transmission networks in order to inform public health actions targeting SARS-CoV-2 spread. Methods: We used whole genome SARS-CoV-2 sequences derived from ten European regions belonging to eight countries to perform phylogenetic and phylodynamic analysis. We developed dedicated bioinformatics pipelines to identify regional MTCs and to assess demographic factors potentially associated with their formation. Results: The total number and the scale of MTCs varied from small household clusters identified in all regions, to a super-spreading event found in Uusimaa-FI. Specific age groups were more likely to belong to MTCs in different regions. The clustered sequences referring to the age groups 50–100 years old (y.o.) were increased in all regions two weeks after the establishment of the lockdown, while those referring to the age group 0–19 y.o. decreased only in those regions where schools’ closure was combined with a lockdown. Conclusions: The spatiotemporal profiling of the SARS-CoV-2 MTCs can be a useful tool to monitor the effectiveness of the interventions and to reveal cryptic transmissions that have not been identified through contact tracing
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