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311.
The reconstruction of Aurignacian points is the first step towards the statistical enquiry of the totality of points in a region at Aurignacian times. We present a method of buckling and calculus by strength of material with the reconstruction of the Dzeravá skala points as a practical application. This collection has a double interest. It offers an analogy to the direction of the two most rich collections of Aurignacian points in Central Europe: Istállósk? and Poto?ka zijalka. After the determination of the original length of these points, we can examine the question of split-base and “shouldered” points, artificial or natural splits, and discuss the curious points with a presumed hole in the hafting zone. Theoretical notions are resumed in the appendix. The theory cannot offer an answer to practical problems. Only experiments permit to determine the zones of rupture and the length of lacking fragments when the sections are variable, the impact is excentric and the hafting not perfect.  相似文献   
312.
A small molecule that safely mimics the ability of dietary restriction (DR) to delay age-related diseases in laboratory animals is greatly sought after. We and others have shown that resveratrol mimics effects of DR in lower organisms. In mice, we find that resveratrol induces gene expression patterns in multiple tissues that parallel those induced by DR and every-other-day feeding. Moreover, resveratrol-fed elderly mice show a marked reduction in signs of aging, including reduced albuminuria, decreased inflammation, and apoptosis in the vascular endothelium, increased aortic elasticity, greater motor coordination, reduced cataract formation, and preserved bone mineral density. However, mice fed a standard diet did not live longer when treated with resveratrol beginning at 12 months of age. Our findings indicate that resveratrol treatment has a range of beneficial effects in mice but does not increase the longevity of ad libitum-fed animals when started midlife.  相似文献   
313.
Oak gallwasps (Hymenoptera, Cynipidae, Cynipini) are one of seven major animal taxa that commonly reproduce by cyclical parthenogenesis (CP). A major question in research on CP taxa is the frequency with which lineages lose their sexual generations, and diversify as purely asexual radiations. Most oak gallwasp species are only known from an asexual generation, and secondary loss of sex has been conclusively demonstrated in several species, particularly members of the holarctic genus Andricus. This raises the possibility of widespread secondary loss of sex in the Cynipini, and of diversification within purely parthenogenetic lineages. We use two approaches based on analyses of allele frequency data to test for cryptic sexual generations in eight apparently asexual European species distributed through a major western palaearctic lineage of the gallwasp genus Andricus. All species showing adequate levels of polymorphism (7/8) showed signatures of sex compatible with cyclical parthenogenesis. We also use DNA sequence data to test the hypothesis that ignorance of these sexual generations (despite extensive study on this group) results from failure to discriminate among known but morphologically indistinguishable sexual generations. This hypothesis is supported: 35 sequences attributed by leading cynipid taxonomists to a single sexual adult morphospecies, Andricus burgundus, were found to represent the sexual generations of at least six Andricus species. We confirm cryptic sexual generations in a total of 11 Andricus species, suggesting that secondary loss of sex is rare in Andricus.  相似文献   
314.
The PGC-1 coactivators are important regulators of oxidative metabolism. We previously demonstrated that LRP130 is a binding partner of PGC-1alpha, required for hepatic gluconeogenesis. LRP130 is the gene mutated in Leigh syndrome French Canadian variant, a rare neurodegenerative disease. The importance of LRP130 in other, non-hepatocyte biology remains obscure. To better understand PGC-1 coactivator function in brown fat development, we explored the metabolic role of LRP130 in brown adipocyte differentiation. We show that LRP130 is preferentially enriched in brown fat compared with white, and induced in a PGC-1-dependent manner during differentiation. Despite intact PGC-1 coactivator expression, brown fat cells deficient for LRP130 exhibit attenuated expression of several genes characteristic of brown fat, including uncoupling protein 1. Oxygen consumption studies support a specific defect in proton leak due to attenuated uncoupling protein 1 expression. Notably, brown fat cell development common to both PGC-1 coactivators is governed by LRP130. Conversely, the cAMP response controlled by PGC-1alpha is not regulated by LRP130. These data implicate LRP130 in brown fat cell development and differentiation.  相似文献   
315.
There is increasing evidence that TGF-beta family member cytokine bone morphogenetic protein (BMP)-4 plays different pathophysiological roles in the pulmonary and systemic circulation. Upregulation of BMP-4 has been linked to atherosclerosis and hypertension in the systemic circulation, whereas disruption of BMP-4 signaling is associated with the development of pulmonary hypertension. To test the hypothesis that BMP-4 elicits differential effects in the pulmonary and systemic circulation, we compared the prooxidant and proinflammatory effects of BMP-4 in cultured human coronary arterial endothelial cells (CAECs) and pulmonary arterial endothelial cells (PAECs). We found that BMP-4 (from 0.3 to 10 ng/ml) in CAECs increased O(2)(*-) and H(2)O(2) generation, induced NF-kappaB activation, upregulated ICAM-1, and induced monocyte adhesiveness to ECs. In contrast, BMP-4 failed to induce oxidative stress or endothelial activation in PAECs. Also, BMP-4 treatment impaired acetylcholine-induced relaxation and increased O(2)(*-) production in cultured rat carotid arteries, whereas cultured rat pulmonary arteries were protected from these adverse effects of BMP-4. Thus, we propose that BMP-4 exerts prooxidant, prohypertensive, and proinflammatory effects only in the systemic circulation, whereas pulmonary arteries are protected from these adverse effects of BMP-4. The vascular bed-specific endothelial effects of BMP-4 are likely to contribute to its differential pathophysiological role in the systemic and pulmonary circulation.  相似文献   
316.

Background

The prevalence of obesity with aging is escalating alarmingly; and pelvic organ prolapse (POP) and stress urinary incontinence (SUI) are now becoming a growing epidemic among the elderly. Synthetic transvaginal mesh has been employed with increasing popularity in the treatment of POP and is usually highly effective in controlling the principal symptoms of prolapse. However, studies have reported that mesh operations provide fairly unfavorable SUI cure rates. Therefore, additional anti-incontinence surgical strategies are increasingly being scrutinized to achieve better postoperative continence without any significant side-effects for patients with both POP and SUI. We hypothesize that the modification with the fixing of the mesh to the mid-urethra is superior to the original transvaginal mesh operation (TVM) with regard to anti-incontinence.

Methods

One hundred and thirty patients diagnosed with POP–Q II–III and concomitant SUI requiring surgical treatment will be included in this prospective, randomized, double-blind, controlled clinical trial. Patients will be randomly allocated to receive either original TVM (TVM group, n?=?65) or modified TVM surgery (mTVM group, n?=?65). As the primary outcome parameter, we will evaluate the objective SUI and POP cure rates. Secondary endpoints include postoperative morbidity as assessed with the International Urogynaecological Association classification and subjective prolapse and incontinence cure rates reported by questionnaires.

Discussion

Recognizing the importance of an additional surgical procedure for anti-incontinence management, we aim to investigate whether a stabilizing suturing of the mesh to the mid-urethra delivers superior SUI correction compared to the original prosthesis surgery.

Trial registration

ClinicalTrials.gov, NCT02935803. Registered on 20 May 2016.
  相似文献   
317.

Introduction

Fish fraud detection is mainly carried out using a genomic profiling approach requiring long and complex sample preparations and assay running times. Rapid evaporative ionisation mass spectrometry (REIMS) can circumvent these issues without sacrificing a loss in the quality of results.

Objectives

To demonstrate that REIMS can be used as a fast profiling technique capable of achieving accurate species identification without the need for any sample preparation. Additionally, we wanted to demonstrate that other aspects of fish fraud other than speciation are detectable using REIMS.

Methods

478 samples of five different white fish species were subjected to REIMS analysis using an electrosurgical knife. Each sample was cut 8–12 times with each one lasting 3–5 s and chemometric models were generated based on the mass range m/z 600–950 of each sample.

Results

The identification of 99 validation samples provided a 98.99% correct classification in which species identification was obtained near-instantaneously (≈?2 s) unlike any other form of food fraud analysis. Significant time comparisons between REIMS and polymerase chain reaction (PCR) were observed when analysing 6 mislabelled samples demonstrating how REIMS can be used as a complimentary technique to detect fish fraud. Additionally, we have demonstrated that the catch method of fish products is capable of detection using REIMS, a concept never previously reported.

Conclusions

REIMS has been proven to be an innovative technique to help aid the detection of fish fraud and has the potential to be utilised by fisheries to conduct their own quality control (QC) checks for fast accurate results.
  相似文献   
318.
In this paper we determine the noise properties needed for unconditional security for the ideal Kirchhoff-Law-Johnson-Noise (KLJN) secure key distribution system using simple statistical analysis. It has already been shown using physical laws that resistors and Johnson-like noise sources provide unconditional security. However real implementations use artificial noise generators, therefore it is a question if other kind of noise sources and resistor values could be used as well. We answer this question and in the same time we provide a theoretical basis to analyze real systems as well.  相似文献   
319.
320.
To clarify the contribution of intracellularCa2+ concentration([Ca2+]i)-dependent and -independentsignaling mechanisms in arteriolar smooth muscle (aSM) to modulation ofarteriolar myogenic tone by nitric oxide (NO), released in response toincreases in intraluminal flow from the endothelium, changes in aSM[Ca2+]i and diameter of isolated rat gracilismuscle arterioles (pretreated with indomethacin) were studied byfluorescent videomicroscopy. At an intraluminal pressure of 80 mmHg, [Ca2+]i significantly increased andmyogenic tone developed in response to elevations of extracellularCa2+ concentration. The Ca2+ channelinhibitor nimodipine substantially decreased[Ca2+]i and completely inhibited myogenictone. Dilations to intraluminal flow (that were inhibited byN-nitro-L-arginine methyl ester)or dilations to the NO donorS-nitroso-N-acetyl-DL-penicillamine (that were inhibited by the guanylate cyclase inhibitor1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one) were notaccompanied by substantial decreases in aSM[Ca2+]i. 8-Bromoguanosine cGMP and thecGMP-specific phosphodiesterase inhibitor zaprinast significantlydilated arterioles yet elicited only minimal decreases in[Ca2+]i. Thus flow-induced endothelialrelease of NO elicits relaxation of arteriolar smooth muscle by acGMP-dependent decrease of the Ca2+ sensitivity of thecontractile apparatus without substantial changes in thepressure-induced level of [Ca2+]i.

  相似文献   
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