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Examining the frequency and distribution of hybrids across contact zones provide insights into the factors mediating hybridization. In this study, we examined the effect of habitat and climate on hybridization patterns for three phenotypically, genetically, and ecologically distinct groups of the Canada jay (Perisoreus canadensis) in a secondary contact zone in western North America. Additionally, we tested whether the frequency of hybridization involving the three groups (referred to as Boreal, Pacific and Rocky Mountain morphotypes) is similar across the hybrid zones or whether some pairs have hybridized more frequently than others. We reanalyzed microsatellite, mtDNA and plumage data, and new microsatellite and plumage data for 526 individuals to identify putative genetic and phenotypic hybrids. The genetically and phenotypically distinct groups are associated with different habitats and occupy distinct climate niches across the contact zone. Most putative genetic hybrids (86%) had Rocky Mountain ancestry. Hybrids were observed most commonly in intermediate climate niches and in habitats where Engelmann spruce (Picea engelmannii) overlaps broadly with boreal and subalpine tree species. Our finding that hybrids occupy intermediate climate niches relative to parental morphotypes matches patterns for other plant and animal species found in this region. This study demonstrates how habitat and climate influence hybridization patterns in areas of secondary contact and adds to the growing body of research on tri-species hybrid zones.

Conventional fuels for vehicles, which are non-renewable energy sources, are still currently in use. To reduce noise and CO2emissions, electric vehicles dictate a remarkable research and developments in order to reach a viable solution. Electrified vehicles have a dedicated energy store, usually batteries, to improve emissions or replace the conventional energy source with electric power. For almost a decade now, the use of Li-ion batteries as a source of energy for electric vehicles has exploded, but there are also many questions about their safety. This study is dedicated to compare the results obtained by experiment with the result obtained by simulation about mechanical behavior of an 18650 Li-ion cell under pinch indentation.

Lithium-ion batteries (LIBs) are an important component of the automotive industry in terms of electrification. Regarding their safety, the researchers perform different scenarios in which they follow closely and carefully their behavior under the action of induced requests. The most common mechanical abuse tests are three-point bending, simple bending, deformation with hemispherical punch head and nail penetration. In this article, the behavior of the 21700 lithium-ion cell is debated and the results are compared. First, experimental tests are performed and the results are validated with FEM model, to check the veracity of the experiment. Also, the interpreted results can be used in future researches regarding safety of batteries.

Humankind is facing more and more specific problems in technology area and the concept of using controlled or autonomous air systems knows as drone is present in several industries caused by the variety of options they provide. To connect the problems with the drone usage and to achieve a reliable solution drones needs optimization and technical characteristics to be changed. In the agriculture field they must offer an accurate construction of the nacelle so the air flow can be controlled properly so the process of phytosanitary treatment can offer more precision and efficiency. The paper suggests the research of air flow dynamics according to the geometry (conicity) of 4 different nacelle construction at different angles (55°, 65°, 75° and 85°) by numerical analysis method and parameters as velocity, pressure and airspeed.

We have previously shown that the mitochondrial potassium channel Kv1.3 (mtKv1.3) in T lymphocytes is a novel target of Bax. Mutation of Bax at lysine 128 (BaxK128E) abrogates its inhibitory effects on mtKv1.3 and prevents apoptosis. The importance of mtKv1.3 inhibition was underscored by the finding that membrane-permeant Kv1.3 inhibitors induced Bax/Bak-independent cell death and reduced the volume of an mtKv1.3-expressing tumor by 90 in a mouse model. However, the possible involvement of other Kv channels in apoptosis has not been clarified. Here we report that, like Kv1.3, Kv1.1 and Kv1.5 also interact with Bax. Transfection of Kvdeficient lymphocytes with Kv1.1 restores sensitivity to cell death in apoptosis-resistant CTLL-2 lymphocytes. SiRNA down-regulation of Kv1.3 and Kv1.5 expression in macrophages confers resistance to apoptosis. We further report that J774 macrophages express Kv1.3 and Kv1.5 in their mitochondria and that inhibition of both channels with specific membrane-permeant drugs can efficiently induce apoptosis in a macrophage cell line. Thus, our results indicate that the mechanism proposed for Kv1.3 can be extended to other Kv channels and suggest that membrane-permeant drugs may be a novel pharmacological tool for inducing apoptosis in macrophages, important players in the immune system. This result could be exploited for the depletion of tumor-associated macrophages, which have been shown to foster tumor growth.

Various ion channel activities can be recorded by electrophysiological methods in the outer and inner envelope membranes of chloroplasts as well as in the thylakoid membrane. However, most of these channels are poorly characterized from a pharmacological point of view. Furthermore, the molecular identity has been determined only for a few of them, preventing an understanding of their role in plant physiology. By allowing specific ion fluxes across plastidial membranes, these ion channels may either directly or indirectly regulate photosynthesis, as has been hypothesized earlier. We have determined the effect of various ion channel modulators [indole-3-acetic acid, 5-nitro-2-(3-phenylpropylamino)-benzoate, (−)-epigallocatechin-3-gallate, p-chlorophenoxyacetic acid, Konig's polyanion, Cs⁺, Gd³⁺, 4-aminopyridine, tetraethylammonium chloride, charybdotoxin, nimodipine, and cyclosporin A] on the efficiency of photosynthetic oxygen evolution in intact chloroplasts, broken chloroplasts, and isolated thylakoids. The data may improve our understanding of chloroplast ion channels and identifies inhibitors which may be exploited for electrophysiological studies.

The purpose of this study is to evaluate the objective, subjective, and radiographic results of arthroscopic biceps tenotomy in selected patients with rotator cuff tears. Three hundred seven arthroscopic biceps tenotomies were performed in patients with full- thickness rotator cuff tears. Patients were selected for arthroscopic tenotomy if the tear was thought to be irreparable or if the patient was older and not willing to participate in the rehabilitation required after rotator cuff repair. Patients were evaluated clinically and radiographically at a mean of 57 months' follow-up (range, 24-168 months). The mean Constant score increased from 48.4 points preoperatively to 67.6 points postoperatively (P < .0001). Eighty-seven percent of patients were satisfied or very satisfied with the result. The acromiohumeral interval decreased by a mean of 1.3 mm during the follow-up period and was associated with a longer duration of follow-up (P < .0001). Preoperatively, 38% of patients had glenohumeral arthritis; postoperatively, 67% of patients had glenohumeral arthritis. Concomitant acromioplasty was statistically associated with better subjective and objective results only in patients with an acromiohumeral distance greater than 6 mm. Fatty infiltration of the rotator cuff musculature had a negative influence on both the functional and radiographic results (P < .0001). Arthroscopic biceps tenotomy in the treatment of rotator cuff tears in selected patients yields good objective improvement and a high degree of patient satisfaction. Despite these improvements, arthroscopic tenotomy does not appear to alter the progressive radiographic changes that occur with long-standing rotator cuff tears.

Gluten sensitive enteropathy has various manifestations, of which the two major forms are classical coeliac disease (cCD) and dermatitis herpetiformis (DH). In cCD predominantly the small intestine is affected, whereas in DH also the skin is affected showing typical rash and IgA deposits. The symptoms in both forms are dependent on gluten intake. The factors diversifying these two clinical outcomes are unknown. In the present report we evaluated the role of the major genetic susceptibility locus, HLA DQ , in 25 families, in which both forms of the disease, cCD and DH, occurred in siblings. By using the family-based approach it can be assumed that within each family variation in environmental factors is substantially lower than in the standard case-control setting, and also the problems related to population stratification can be avoided. Results from the Finnish family material with 25 discordant and 85 concordant sib pairs, and from additional case-control material comprising 71 unrelated Hungarian DH and 68 cCD patients, together indicated that the HLA DQ locus did not differ between the two major outcomes of gluten sensitive enteropathy. The non-HLA DR;DQ factors are critical for the different clinical manifestations of gluten sensitivity.

The aim of the study was to evaluate the hormonal (focusing on the urinary steroid profile) and clinical effects of chronic gonadotropin-releasing hormone (GnRH) agonist treatment in patients with polycystic ovary syndrome (PCOS) suffering from hirsutism. A long-acting GnRH agonist was administered for 6 months in eight PCOS patients. Hormonal effects were measured by determining serum luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin, testosterone and estradiol concentrations, and by profiling urinary steroids using capillary gas chromatography of 24-hour urine samples. To evaluate 5α-reductase enzyme activity, the ratios of androsterone to etiocholanolone and 5α-tetrahydrocortisol to tetrahydrocortisol were calculated in urine samples. The ratio of androgen to Cortisol metabolites was also determined before, and 3 and 6 months after therapy.LH and estradiol levels were suppressed significantly after the first injection and testosterone after the second injection of the GnRH agonist. Thus, serum testosterone was normalized. Ratios of urinary steroids reflecting 5α-reductase enzyme activity (androsterone to etiocholanolone and 5α-tetrahydrocortisol to tetrahydrocortisol) and the ratio of androgen to Cortisol metabolites decreased significantly after 3 months of treatment. Degree of hirsutism, assessed by Ferriman-Gallwey score, diminished after 6 months, but not significantly.In conclusion, our data show that long-acting GnRH agonist treatment of PCOS patients is effective in reducing serum and urinary androgen levels, but it is not accompanied by an effective reduction in hirsutism during a 6-month treatment period. A longer or a combined treatment would be needed to achieve significant improvement in hirsutism. Gas chromatographic profiling of urinary steroids and the use of specific ratios of the excreted metabolites seems to be a sensitive tool both in the diagnosis of PCOS and in monitoring ovarian suppression.

Screening drugs used in obstetrical practice for effects on steroid hormone synthesis revealed that phenobarbital inhibited progesterone synthesis in MA-10 Leydig tumor cells. The inhibition was apparently a drug class effect since it could be reproduced by other barbiturates. Barbiturate blockade was reversible and could be bypassed in the MA-10 cells by using 22-hydroxycholesterol. Human granulosa cell progesterone synthesis was also inhibited in a dose dependent fashion by phenobarbital, secobarbital and barbituric acid. Significant inhibition occurred in dose ranges that would be therapeutic for treating epilepsy. From these data we conclude that barbiturates block steroidogenesis by inhibiting cholesterol transport to the cholesterol side chain cleavage enzyme.

To reveal the well known effect of smoking on the incidence of early abortion, the possible effects of cigarette alkaloids on progesterone and estradiol synthesis were investigated. A suspected cause for early spontaneous abortion is corpus luteum insufficiency. The present experiments evaluate the effects of cigarette smoke alkaloids on progesterone and estradiol biosynthesis. Human granulosa cells were obtained from patients undergoing in vitro fertilization and embryo transfer treatment because of infertility. Incubation of the granulosa cells with cotinine, anabasine, with the combination of nicotine, cotinine and anabasine, or with an aqueous extract of cigarette smoke resulted in inhibition of progesterone synthesis. The alkaloids and smoke extract decreased the DNA content of the culture dish. These latter findings suggested a cytotoxic effect of the alkaloids. Both cotinine and anabasine slightly stimulated the synthesis of normalized estradiol. However, nicotine, combination of all three alkaloids, and cigarette smoke extract had no significant influence on estradiol production. Taken together, these data would suggest that cigarette alkaloids inhibit cellular progesterone synthesis both by inhibiting progesterone synthesis and by causing less specific toxic effects to the cell. In contrast, cigarette smoke alkaloids slightly stimulated or had no effect on estradiol production. These concomitant actions of cigarette alkaloids partly explain the higher incidence of early abortion in pregnant women who smoke.

Apoptosis (programmed cell death), a physiological mechanism eliminating abundant and potentially harmful cells, is triggered by a variety of stimuli including activation of distinct receptors. The machinery mediating CD95 receptor-induced apoptosis includes caspases, ceramide, kinases, Ras and Rac, formation of O2–, mitochondrial proteins, inhibition of K+channels, activation of Cl–channels, and osmolyte release.

In a reversed-phase HPLC method, optimized for resolution and quantitation of nucleosides and nucleobases in human term placental extracts, guanine coeluted with hypoxanthine. Three numerical techniques that treat spectral data generated by photodiode-array detection to yield indices of peak purity were compared for sensitivity of on-line recognition of overlapped guanine and hypoxanthine peaks in chromatograms of 7.0 μM hypoxanthine containing 0.075-0.54 μM guanine. These techniques were purity parameter, the average wavelength of a peak spectrum (λw) peak area ratio, and peak absorbance ratio. Purity parameter of a 7.0 μM hypoxanthine peak containing 1% guanine was significantly different from that of pure hypoxanthine (P< 0.01); peak area and peak absorption ratios were four and seven times, respectively, less sensitive than purity parameter. In chromatograms of human term placental extracts, purity parameter values generated on-line signalled the presence of guanine in hypoxanthine peaks. Quantitation of coelutiaghypoxanthine and guanine was performed on-line from dual-wavelength detection at 249 and 278 nm via calibration curves for both analytes at these wavelengths. Hypoxanthine and guanine concentrations in seven samples from five human term placentas were 41-161 and 3-76 nmol/g, respectively. These findings demonstrate that on-line signalling of hypoxanthine and guanine coelution is achieved by purity parameter, area ratio, and absorbance ratio, that purity parameter is the most sensitive index of coelution, and that quantitation of the coeluting analytes can be performed on-line. These approaches should be applicable to recognition and quantitation of coeluting analytes in chromatograms ofmixtures of nucleosides and nucleobases such as occur in extracts of other tissues.

The conversion of 5-ß-D-ribofuranosyl cyanides to the corresponding 2-ß-ribofuranosylbenzothiazoles (under the influence of 2-aminothiophenol) and to 5-ß-glycosyltetrazoles (by reaction with sodium azide and ammonium chloride) is described. It is shown that acylation of the latter structures with acetic anhydride or benzoyl chloride is a convenient method for the synthesis of 5-ß-glycosyl-1,3,4-oxadiazoles.

Conclusions: Emission and excitation spectra as well as the lifetime and the Judd-Ofelt parameters were determined for the different sites occupied by Eu3+ ions in a fluorzirconate glass. As has been observed in borate glasses, the Ω4 parameter increases with the excitation energy of the7F0→5D0 transition, while Ω4 is nearly constant [5, 6]. These parameters are lower than in borate glasses by a factor of close to 3. The optical properties of the Eu3+ ions in the studied glass appear to be dominated by only one class of sites; however, the presence of a second class of sites is possible. Efficient energy transfer from Eu3+ to Ho3+ is observed, but the energy transfer parameter does not depend appreciably on the excitation wavelength.

Chromanols, which were recently shown to inhibit cAMP‐mediated Cl−secretion in colon crypts via a blockade of a cAMP‐activated K+conductance, were analyzed for their effects on distinct cloned K+channels expressed in Xenopusoocytes. The lead chromanol 293B specifically inhibited IsKchannels with an IC50of 7 μmol/l without affecting the delayed rectifier Kv1.1 or the inward rectifier Kir2.1. Moreover, several other chromanols displayed the same rank order of potency for IsKinhibition as demonstrated in colon crypts. Finally, we tested the effects of the previously described IsKblocker azimilide on cAMP mediated Cl−secretion in rat colon crypts. Similar to 293B azimilide inhibited the forskolin induced Cl−secretion. These data suggest that IsKprotein induced K+conductances are the targets for the chromanol 293B and its analogues, and azimilide.

Release of histamine (H) by ischemia-reperfusion injury was investigated in isolated rat hearts (Langendorff model). The effect of 10, 15, 20, 25, 30, 40 and 60 min ischemia (n=10 each) on H in the coronary effluent and in cardiac tissue was studied after 4 min reperfusion. Release of creatine kinase and lactate dehydrogenase in the coronary effluent increased with time of ischemia. Tissue H increased from 95±10 ng/g rat heart (mean±SEM) before ischemia to max 148±10 ng/g after 20 min ischemia (p<0.002), and increased also after 15 (p<0.01), 25 (p<0.01), 25 (p<0.01), and 30 min (p<0.045). H in the coronary effluent increased after 15 (from 16±3 to 26±2 pmol/min,p<0.044), 30 (26±6 pmol/min,p<0.027), and 60 min ischemia (47±6 pmol/min,p<0.0044). Release of H during ischemia-reperfusion is neither dependent on the severity of the ischemic insult, nor on the level of tissue H.

Receptor-selective opioid agonists have been found to suppress the capacity of macrophages to ingest opsonized sheep erythrocytes. In an effort to characterize the immunomodulatory activity of opioids further, experiments were done to examine the uptake of Candida albicans by opioid-treated murine peritoneal macrophages. It was found that treatment with morphine and selective mu, i.e., DAMGO, delta, i.e., DPDPE, and kappa, i.e., trans-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl) cyclohexyl]benzene-acetamide methanesulfonate, receptor agonists resulted a concentration-dependent suppression of both the percentage of phagocytic cells and the average number of ingested yeasts. Antagonists selective for mu, i.e., H-D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2, delta, i.e., naltrindole, and kappa, i.e., norbinaltorphimine, opioid receptors completely blocked the respective receptor-selective agonist-induced suppression. These results suggest that the mu, delta and kappa opioid receptors can modulate macrophage function.

The release of Ketoprofen from the matrix model of TTS were studied. It may be concluded that the pharmaceutical availability of the drug can be regulated by the type and thickness of the matrix. Quantitation of the active agent in the dissolution medium was done by UV-spectroscopy.The results obtained by the rotating cylinder method were compared to another method utilizing a modified Stricker cell.

The membrane-bound 43,000-Mr penicillin-binding protein no. 6 (PBP6) of Enterococcus hirae consists of a 30,000-Mr DD-peptidase/penicillin-binding domain and a approximately 130-residue C-terminal appendage. Removal of this appendage by trypsin proteolysis has no marked effect on the catalytic activity and penicillin-binding capacity of the PBP. Anchorage of the PBP in the membrane appears to be mediated by a short 15-20-residue stretch at the C-terminal end of the appendage. The sequence of the 50-residue N-terminal region of the PBP shows high degree of homology with the sequences of the corresponding regions of the PBPs5 of Escherichia coli and Bacillus subtilis. On this basis the active-site serine residue occurs at position 35 in the enterococcal PBP.