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751.
The white-rot fungi basidiomycetes Pleurotus sp. BCCB068 and Pleurotus tailandia were used to degrade oat-spelt xylan under submerged fermentation over a period of 40 days. Activities of endo-1,4-β-xylanase and β-xylosidase and xylan degradation products were determined. Xylan degradation by Pleurotus sp. BCCB068 and P. tailandia reached 75.1% and 73.4%, respectively. The formation of xylooligosaccharides and the simple sugars xylose, arabinose, cellobiose, mannose, and maltose were observed for both strains. The xylan degradation exhibited by these Pleurotus strains indicates they have potential for use in biotechnological processes related to degradation of hemicellulose sources.  相似文献   
752.

Background

Listening to music is amongst the most rewarding experiences for humans. Music has no functional resemblance to other rewarding stimuli, and has no demonstrated biological value, yet individuals continue listening to music for pleasure. It has been suggested that the pleasurable aspects of music listening are related to a change in emotional arousal, although this link has not been directly investigated. In this study, using methods of high temporal sensitivity we investigated whether there is a systematic relationship between dynamic increases in pleasure states and physiological indicators of emotional arousal, including changes in heart rate, respiration, electrodermal activity, body temperature, and blood volume pulse.

Methodology

Twenty-six participants listened to self-selected intensely pleasurable music and “neutral” music that was individually selected for them based on low pleasure ratings they provided on other participants'' music. The “chills” phenomenon was used to index intensely pleasurable responses to music. During music listening, continuous real-time recordings of subjective pleasure states and simultaneous recordings of sympathetic nervous system activity, an objective measure of emotional arousal, were obtained.

Principal Findings

Results revealed a strong positive correlation between ratings of pleasure and emotional arousal. Importantly, a dissociation was revealed as individuals who did not experience pleasure also showed no significant increases in emotional arousal.

Conclusions/Significance

These results have broader implications by demonstrating that strongly felt emotions could be rewarding in themselves in the absence of a physically tangible reward or a specific functional goal.  相似文献   
753.

Background

The emergency treatment of incisional hernias is infrequent but it can be complicated with strangulation or obstruction and in some cases the surgical approach may also include an intestinal resection with the possibility of peritoneal contamination. Our study aims at reporting our experience in the emergency treatment of complicated incisional hernias.

Methods

Since January 1999 till July 2008, 89 patients (55 males and 34 females) were treated for complicated incisional hernias in emergency. The patients were divided in two groups: Group I consisting of 33 patients that were treated with prosthesis apposition and Group II, consisting of 56 patients that were treated by performing a direct abdominal wall muscles suture.

Results

All the patients underwent a 6-month follow up; we noticed 9 recurrences (9/56, 16%) in the patients treated with direct abdominal wall muscles suture and 1 recurrence (1/33, 3%) in the group of patients treated with the prosthesis apposition.

Conclusions

According to our experience, the emergency treatment of complicated incisional hernias through prosthesis apposition is always feasible and ensures less post-operative complications (16% vs 21,2%) and recurrences (3% vs 16%) compared to the patients treated with direct muscular suture.  相似文献   
754.
755.
This work presents a theoretical study of gallium arsenide (GaAs) nanotubes obtained from the (100), (110) and (111) crystal planes of zincblende structure in order to evaluate the electronic properties. The DFT/B3LYP/6-31G method was used to predict structures and stabilities. It was found that nanotubes from the (110) crystal plane tended to be the most stable. The results for average diameter and bond length obtained for optimized nanotube geometries show that nanotubes constructed from the (100) plane have a hyperbolic format, while (110) or (111) nanotubes have a conical format. This difference in relation to geometry introduces regions with different charge concentrations along the tube. From the calculated values for the gap it follows that increasing the number of atoms per layer causes a displacement of the frontier orbitals with a reduction in the gap, yielding characteristics of a semiconductor material.  相似文献   
756.
757.
Cryptococcosis is a mycosis caused by yeasts of genus Cryptococcus, mainly the species C. neoformans and C. gattii that can affect humans and animals. These yeasts are widely distributed in the environment and are typically associated with avian droppings and decaying wood. Most infections are related to the respiratory tract, but the central nervous system and cutaneous lesions are also reported in the literature. The present report is a case of cryptococcosis in an 18-month-old unspayed female English Bulldog with the main complaint of weight loss and diarrhea. The presence of two large masses observed in an ultrasound examination leads us to perform an exploratory laparotomy. Considering the size of the lesion and the impossibility of owner to provide intensive care, the consent for euthanasia was requested. The postmortem diagnosis of cryptococcosis was revealed by cytological evaluation, and the involvement of C. gattii VGII was confirmed by isolation and identification tests as well as by the detection of the URA5 gene restriction fragment length polymorphism PCR analysis. Reports in the literature of the involvement of Cryptococcus in gastrointestinal lesions are rare in both human and veterinary medicine. Data about different forms of cryptococcosis are important to provide more knowledge of uncommon clinical presentations of this yeast and therefore improve the diagnoses and decisions for the best therapy.  相似文献   
758.
This work deals with the dosimetric features of a particular phenolic compound (IRGANOX 1076®) for dosimetry of clinical photon beams by using electron spin resonance (ESR) spectroscopy. After the optimization of the ESR readout parameters (namely modulation amplitude and microwave power) to maximise the signal without excessive spectrum distortions, basic dosimetric properties of laboratory-made phenolic dosimeters in pellet form, such as reproducibility, dose–response, sensitivity, linearity and dose rate dependence were investigated. The dosimeters were tested by measuring the depth dose profile of a 6 MV photon beam. A satisfactory intra-batch reproducibility of the ESR signal of the manufactured dosimeters was obtained. The ESR signal proved to increase linearly with increasing dose in the investigated dose range 1–13 Gy. The presence of an intrinsic background signal limits the minimum detectable dose to a value of approximately 0.6 Gy. Reliable and accurate assessment of the dose was achieved, independently of the dose rate. Such characteristics, together with the fact that IRGANOX 1076® is almost tissue-equivalent, and the stability of the ESR signal, make these dosimeters promising materials for ESR dosimetric applications in radiotherapy.  相似文献   
759.
Coral Reefs - Ocean acidification is expected to intensify due to increasing levels in the partial pressure of atmospheric CO2 (pCO2). This could negatively affect major calcifying reef organisms....  相似文献   
760.
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