We analyzed the asymmetry of Autler–Townes doublets in the calculated photoelectron energy spectra for the two-photon ionization of the hydrogen atom by an intense short laser pulse that resonantly ...couples its ground state with the excited 2p state. The spectra are calculated applying the method of time-dependent amplitudes using two approaches of different level of approximation. The first approach involves solving a complete set of equations for amplitudes, which, in addition to amplitudes of coupled (1s, 2p) and continuous states, also includes the amplitudes of other discrete (nonessential) states. The second approach is the three-level model that includes only the amplitudes of the two coupled states and those of continuum states. By comparing the spectra obtained using these two approaches it is confirmed that the shift of the Autler–Townes doublets, which exists only in the spectra obtained by solving the full set of equations, can be attributed to the AC Stark shift, which is a consequence of the coupling with nonessential states. Finally, it was found that the asymmetry in the intensity of the Autler–Townes doublet components, which appears in the spectra obtained using both computational approaches, is primarily due to the decrease in the transition probability between the 2p and continuum states with increasing photoelectron energy.
Graphical Abstract
During diapause, a state of temporarily arrested development, insects require low winter temperatures to suppress their metabolism, conserve energy stores and acquire cold hardiness. A warmer winter ...could, thus, reduce diapause incidence and duration in many species, prematurely deplete their energy reserves and compromise post-diapause fitness. In this study, we investigated the combined effects of thermal stress and the diapause program on the expression of selected genes involved in antioxidant defense and heat shock response in the European corn borer
. By using qRT-PCR, it has been shown that response to chronic heat stress is characterized by raised mRNA levels of
and
, two important genes of the antioxidant defense system, as well as of
and, somewhat, of
, two major heat shock response proteins. On the other hand, the expression of
,
and
was discontinuous in the latter part of diapause, or was strongly controlled by the diapause program and refractory to heat stress, as was the case for
and
, genes encoding two metal storage proteins crucial for metal ion homeostasis. This is the first time that the effects of high winter temperatures have been assessed on cold-hardy diapausing larvae and pupae of this important corn pest.
The European corn borer
Ostrinia nubilalis
is a pest species, whose fifth instar larvae gradually develop cold hardiness during diapause. The physiological changes underlying diapause progression and ...cold hardiness development are still insufficiently understood in insects. Here, we follow a complex of changes related to energy metabolism during cold acclimation (5°C) of diapausing larvae and compare this to warm-acclimated (22°C) and non-diapause controls. Capillary electrophoresis of nucleotides and coenzymes has shown that in gradually cold-acclimated groups concentrations of ATP/ADP and, consequently, energy charge slowly decrease during diapause, while the concentration of AMP increases, especially in the first months of diapause. Also, the activity of cytochrome
c
oxidase (COX), as well as the concentrations of NAD
+
and GMP, decline in cold-acclimated groups, until the latter part of diapause, when they recover. Relative expression of NADH dehydrogenase (
nd1
), coenzyme Q-cytochrome
c
reductase (
uqcr
), COX, ATP synthase (
atp
), ADP/ATP translocase (
ant
), and prohibitin 2 (
phb2
) is supressed in cold-acclimated larvae during the first months of diapause and gradually increases toward the termination of diapause. Contrary to this, NADP
+
and UMP levels significantly increased in the first few months of diapause, after gradual cold acclimation, which is in connection with the biosynthesis of cryoprotective molecules, as well as regeneration of small antioxidants. Our findings evidence the existence of a cold-induced energy-saving program that facilitates long-term maintenance of larval diapause, as well as gradual development of cold hardiness. In contrast, warm acclimation induced faster depletion of ATP, ADP, UMP, NAD
+
, and NADP
+
, as well as higher activity of COX and generally higher expression of all energy-related genes in comparison to cold-acclimated larvae. Moreover, such unusually high metabolic activity, driven by high temperatures, lead to premature mortality in the warm-acclimated group after 2 months of diapause. Thus, our findings strongly support the importance of low temperature exposure in early diapause for gradual cold hardiness acquisition, successful maintenance of the resting state and return to active development. Moreover, they demonstrate potentially adverse effects of global climate changes and subsequent increase in winter temperatures on cold-adapted terrestrial organisms in temperate and subpolar regions.
Purpose. This proof-of-concept study investigated whether feedback-mediated exercise (FME) of the affected arm of hemiplegic patients increases patient motivation and promotes greater improvement of ...motor function, compared to no-feedback exercise (NFE). Method. We developed a feedback-mediated treatment that uses gaming scenarios and allows online and offline monitoring of both temporal and spatial characteristics of planar movements. Twenty poststroke hemiplegic inpatients, randomly assigned to the FME and NFE group, received therapy five days a week for three weeks. The outcome measures were evaluated from the following: (1) the modified drawing test (mDT), (2) received therapy time—RTT, and (3) intrinsic motivation inventory—IMI. Results. The FME group patients showed significantly higher improvement in the speed metric ( P < 0.01 ), and smoothness metric ( P < 0.01 ), as well as higher RTT ( P < 0.01 ). Significantly higher patient motivation is observed in the FME group (interest/enjoyment subscale ( P < 0.01 ) and perceived competence subscale ( P < 0.01 )). Conclusion. Prolonged endurance in training and greater improvement in certain areas of motor function, as well as very high patient motivation and strong positive impressions about the treatment, suggest the positive effects of feedback-mediated treatment and its high level of acceptance by patients.
Radicals in the Bray–Liebhafsky Oscillatory Reaction Stanisavljev, Dragomir R; Milenković, Maja C; Popović-Bijelić, Ana D ...
The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory,
04/2013, Letnik:
117, Številka:
16
Journal Article
Recenzirano
This study investigates the formation of free radicals in the Bray–Liebhafsky (BL) oscillatory reaction. The results indicate that radicals are produced during both monotonous and oscillatory ...dynamics observed as the change of the electron paramagnetic signal (EPR) of the spin-probe TEMPONE. EPR spin-trapping with DEPMPO suggested that the most abundant radical produced in the BL reaction is an iodine-centered radical. The EPR spectrum of the DEPMPO/iodine-centered radical adducts has not been previously reported. This study may aid in establishing a more realistic reaction mechanism of the BL reaction and related chemical oscillators.
The European corn borer (
Ostrinia nubilalis
, Hbn.), enters diapause, a strategy characterized by arrest of development and reproduction, reduction of metabolic rate and the emergence of increased ...resistance to challenging seasonal conditions as low sub-zero winter temperatures. The aim of this study was to investigate the potential role of inorganic elements in the ecophysiology of
O. nubilalis
, analysing their content in the whole body, hemolymph and fat body, both metabolically active, non-diapausing and overwintering diapausing larvae by ICP-OES spectrometer following the US EPA method 200.7:2001.
O nubilalis
as many phytophagous lepidopteran species maintain a very low extracellular sodium concentration and has potassium as dominant cation in hemolymph of their larvae. Changes in hemolymph and the whole body sodium content occur already at the onset of diapause (when the mean environmental temperatures are still high above 0 ºC) and remain stable during the time course of diapause when larvae of this species cope with sub-zero temperatures, it seems that sodium content regulation is rather a part of diapausing program than the direct effect of exposure to low temperatures. Compared to non-diapausing
O. nubilalis
larvae, potassium levels are much higher in the whole body and fat body of diapausing larvae and substantially increase approaching the end of diapause. The concentration of Ca, Mg, P and S differed in the whole body, hemolymph and fat body between non-diapausing and diapausing larvae without a unique trend during diapause, except an increase in their contents at the end of diapause.
Background and Objectives: Oral squamous cell carcinoma (OSCC) accounts for about 95% of oral cancers. It represents a serious public health problem due to the high degree of morbidity and mortality, ...as well as multifactorial etiology. Human papillomavirus (HPV) infection is a well-documented risk factor for oropharyngeal carcinoma, but its role in oral carcinogenesis is still debatable. Our aim was to investigate the differences in the prevalence of high-risk HPV genotypes (HR-HPV) in patients with OSCC and oral potentially malignant disorders (OPMD) from that of healthy subjects. Materials and Methods: A total of 90 subjects were included in the cross-sectional study and divided into three groups of 30 patients each: (1) patients with OSCC, (2) patients with OPMD, and (3) healthy subjects. We examined the presence of 12 HR-HPV genotypes in the obtained biological material (oral swabs) using real-time PCR. Results: One or more of the 12 tested HR-HPV genotypes were detected in 5/30 patients with OSCC and 2/30 with OPMD, whereas no healthy subjects were positive for any of the tested genotypes. There was a statistically significant difference in nodal involvement between HPV-positive and HPV-negative patients with OSCC. Conclusions: Oral HR-HPV was detected in patients with oral premalignant and malignant lesions but not in healthy individuals, suggesting a possible role in oral carcinogenesis. Broad HR-HPV panel testing could increase the sensitivity of risk assessment and screening for OSCC.
Research in previous decades has shown that intrinsically disordered proteins (IDPs) and regions in proteins (IDRs) are as ubiquitous as highly ordered proteins. Despite this, research on IDPs and ...IDRs still has many gaps left to fill. Here, we present an approach that combines wet lab methods with bioinformatics tools to identify and analyze intrinsically disordered proteins in a non-model insect species that is cold-hardy. Due to their known resilience to the effects of extreme temperatures, these proteins likely play important roles in this insect's adaptive mechanisms to sub-zero temperatures. The approach involves IDP enrichment by sample heating and double-digestion of proteins, followed by peptide and protein identification. Next, proteins are bioinformatically analyzed for disorder content, presence of long disordered regions, amino acid composition, and processes they are involved in. Finally, IDP detection is validated with an in-house 2D PAGE. In total, 608 unique proteins were identified, with 39 being mostly disordered, 100 partially disordered, 95 nearly ordered, and 374 ordered. One-third contain at least one long disordered segment. Functional information was available for only 90 proteins with intrinsic disorders out of 312 characterized proteins. Around half of the 90 proteins are cytoskeletal elements or involved in translational processes.
According to recent epidemiological data, annual deaths due to liver disease have increased dramatically, while predictions show that trends will continue to rise in the upcoming years.
Abnormal ...liver blood tests are one of the most common challenges encountered in the primary care setting. The prevalence of mildly elevated transaminase levels is around 10-20% in the general population. The most common causes for the rising burden of liver disease are nonalcoholic fatty liver disease (NAFLD), alcohol-related liver disease (ARLD), and viral hepatitis. With improvements in the management of viral hepatitis over the last decades, the causes for the rising burden of liver disease are shifting toward ARLD and NAFLD. It is well-known that liver disease usually progresses silently for years or decades until the complications of cirrhosis occur. The majority of patients will not require referral to a specialist but will need further assessment in primary care. They should be evaluated for the etiology of liver disease irrespective of the duration of abnormal liver blood tests or unmarked clinical presentation. The evaluation should include a history of alcohol use, a history of medicines or herbal supplements, testing for viral hepatitis, and assessment for NAFLD, especially in obese patients and patients with type 2 diabetes. Abdominal ultrasound should be performed. Key Messages: The general practitioner may contribute significantly by identifying and screening patients at risk for chronic liver disease, as well as prioritize individuals with symptoms or signs of advanced liver disease to the specialist clinic.
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