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According to impression management research, strategic leaders tailor their strategic communication to elicit favorable investor reactions. However, past research on strategy communication view inv...

The chassis is the structure for installing and protecting various circuit units, components and mechanical components inside the electronic device. Vibration fatigue damage is a major form of structural damage, and the vibration fatigue life prediction of the chassis structure is of great significance. The theoretical calculation of structural vibration fatigue life has frequency domain method and time domain method, but it has certain limitations. The theoretical calculation method can not accurately obtain the vibration fatigue life of the structure. According to the actual structure of a chassis, this paper designs and processes a test model of a chassis, applies a random vibration load to the vibration table, and performs vibration fatigue test to predict the vibration fatigue life of a chassis structure. The results show that the vibration fatigue life of the chassis is 40 hours, and fatigue fracture occurs first at the pin.

A novel hollow core photonic crystal fiber (HC-PCF) volatile trace explosive sensor based on the fluorescence quenching was proposed, which was made by coating the allyl tetraphenylethylene (AL-TPE) fluorescence nanofilm onto the inner surface of a HC-PCF core air hole. The theory of the fluorescence quenching was used to analyze the principle of explosives sensing. The effects of the refractive index (RI) and thickness of the fluorescence film on the light intensity at the core inner wall were analyzed theoretically and numerically. The results show that when the RI of the fluorescence film was close to 1.45 and the thickness was close to 150 nm, the normalized intensity of the light field energy at the core inner wall was 9.72%. The HC-PCF fluorescence explosive sensor was fabricated by a multiple cleaving filling technique and a pressure driven coating method. The experimental results show that the sensitivity of 2,4,6-trinitrotoluene (TNT) detection was 0.309/ppb and the minimum detection limit was 0.340 ppb for the sensor with a film thickness of 155 nm. The response time (T90) of 2,4-dinitrotoluene (2,4-DNT) was 120 s for the sensor with a film thickness of 110 nm.

Transfusion auxiliary device by patient manual control dressing is proposed. It is realized by one-way rotation ratchet mechanism, which is consistent of slider-crank mechanism and double pawl ratchet mechanism. Dressing change is automatically realized by patient manual control rope. This reduces the labor intensity of the medical staff, shortens the waiting time of the patients. This device has the advantage of low cost, large market space.

Most of the existing literature about the newsvendor problem mainly focused on choosing an optimal order quantity to maximize the expected profit of a risk-neutral newsvendor. However, some studies pointed out that in practice managers׳ decisions as to order quantities always deviate from the profit-maximization order quantity, which is referred to as decision bias in the newsvendor problem. Then, many studies introduced other preferences rather than risk neutrality of the newsvendor to explain such a decision bias. This paper thus introduces loss aversion to the research of the newsvendor decision bias. We propose a new definition to the loss-averse newsvendor problem–legacy loss, which is defined either as the loss for excess order or the shortage penalty for lost sales when sales time is due. The optimal decisions of a loss-averse newsvendor are obtained through the following three ways: (i) minimizing the expected legacy loss, (ii) minimizing CVaR of legacy loss by combining the CVaR measure in risk management, (iii) minimizing the combination of expected legacy loss and CVaR of legacy loss; and are compared with other existing results. Besides, we present some properties of the optimal decisions as well as relations among them. Some numerical examples are given to illustrate the obtained results.

In cased and perforation completion method widely applied in oil and gas wells, it is difficult to avoid the cementing slurry damage to the lower pore pressure formations. This paper presents a new type of down-hole device, consisting of a packer and valve on each side, to isolate the target interval. Several devices can be connected to the casing strings as necessary and are able to make the cementing slurry bypass such formations. The internal pressure resistance was tested and the pressure loss was calculated when the slurry, at a flow rate of 1.5 m 3 /min, flowing through it. The surface experiment results show that the device can bear 28 MPa without any leakage. Through calculation, the extra pressure loss when normal cementing slurry flows each such device is only about 2.2 MPa, which can satisfy the field requirements. In casing completion operations, multiple devices can be connected to the casing string at the corresponding intervals. Pressuring the liquid in the casing, the pins at the end of the string will be cut off, allowing cement slurry to circulate and bypass such target sections. Two successful field cases applied in coal bed methane wells proved its feasibility. This technology will be able to provide a new promising completion method to avoid cementing slurry damage to formations with lower pore pressure intervals in oil, gas or coal-bed methane wells.

Objective The objective of this study was to retrospectively study the outcomes of large vestibular schwannoma resection through the suboccipital retrosigmoid keyhole approach and emphasize technical details and advantages of surgical resection of large vestibular schwannomas via this approach. Methods From January 2010 to September 2012, 37 consecutive patients (16 men and 21 women) with vestibular schwannoma, 4 cm or greater, received surgical resection through the suboccipital retrosigmoid keyhole approach in our department. Clinical records, radiographic findings, operative summaries, and follow-up data were analyzed retrospectively. Results The mean age of these patients was 45.1 ± 11.6 years. Thirty-six patients underwent primary keyhole surgical removal, and 1 underwent surgery for residual tumor after gamma knife. Gross total tumor removal was accomplished in 35 patients (94.6%), near total resection in 1 (2.7%), and subtotal resection in 1 patient (2.7%). The facial nerve was anatomically intact in all 37 patients (100%). Facial nerve function was assessed in 6 to 12 months after operation. Good function (House-Brackmann facial nerve grade I-II) was present in 81.1% of the patients, whereas acceptable function (grade III) was present in 11.1%. Cerebrospinal fluid (CSF) leakage that required surgical intervention occurred in only 5.4% of the patients, and meningitis occurred in 8.1%. In addition, 3 patients (8.1%) had hydrocephalus requiring a temporary ventricular diversion. There were no deaths. Conclusions The suboccipital retrosigmoid keyhole approach is a valid choice for removing large vestibular schwannomas. Through this approach, cerebellopontine angle can be effectively exposed. Skills to protect facial nerve and extensive experience in microsurgical techniques can significantly improve the total resection rate and postoperative facial nerve function. The authors recommend this approach for patients with vestibular schwannomas larger than 3 to 4 cm.

Emission spectra of a semiconductor bridge (SCB) plasma in a visible range was studied in air. The electron density was measured in a conventional way from the broadening of the A1 I 394.4 nm Stark width. Based on the Saha equation, a system for recording the intensity of Si I 390.5 nm and Si II 413.1 nm was designed. With this technique, the SCB plasma electron density was measured well and accurately. Moreover, the electron density distribution Vs time was acquired from one SCB discharge. The individual result from the broadening of the Al I 394.4 nm Stark width and Saha equation was all in the range of 1015 cm−3 to 1016 cm−3. Finally the presumption of the local thermodynamic equilibrium (LTE) condition was validated.

Objective: This study aimed to detect the association between polymorphisms and haplotype in the ATP-binding cassette transporter A1 (ABCA1) gene and overweight/obese Uyghur patients in China. Methods: A total of 259 overweight/obese patients and 276 normal weight subjects, which were randomly selected from among 3049 adult Uyghurs, were matched for age. We genotyped ABCA1 single nucleotide polymorphisms of rs2515602, rs3890182, rs2275542, rs2230806, rs1800976, and rs4149313. Results: (1) The genotypic and allelic frequencies of rs2515602 and rs4149313 differed between the control group and case group. The genotypic frequency of rs2275542 also differed between the control group and case group (p < 0.05); (2) rs2515602, rs2230806, and rs4149313 polymorphisms were significantly related to risk of overweight/obese; (3) a significant linkage disequilibrium (LD) was observed between the ABCA1 gene rs2275542 with rs3890182 and rs2515602 with rs4149313. (4) the C-C-C-A-G-G, T-C-G-A-G-G, and T-T-G-G-G-A haplotypes were significant in normal weight and overweight/obese subjects (p < 0.05); (5) the levels of HDL-C (rs2515602, rs2275542, rs4149313) in normal weight subjects were different among the genotypes (p < 0.05); the levels of TC, LDL-C and TG (rs1800976) in overweight/obese subjects were different among the genotypes (p < 0.05). Conclusions: The rs2515602, rs4149313, and rs2275542 polymorphisms were associated with overweight/obese conditions among Uyghurs. Strong LD was noted between rs2275542 with rs3890182 and rs2515602 with rs4149313. The C-C-C-A-G-G and T-C-G-A-G-G haplotypes may serve as risk factors of overweight/obesity among Uyghurs. The T-T-G-G-G-A haplotype may serve as a protective factor of overweight/obesity among Uyghurs. Rs2515602, rs2275542, rs4149313, and rs1800976 polymorphisms in the ABCA1 gene may influence lipid profiles.

ObjectiveTo investigate the effectiveness of Shoushen granule, Chinese herbal preparation, on carotid artery elasticity in patients with carotid atherosclerosis.MethodsThe total of 156 carotid atherosclerosis patients were randomly divided into the intervention group (83 cases, treated with Shoushen granule) and the control group (73 cases, treated with pravastatin). Brachial-ankle pulse wave velocity (baPWV) and Ankle-Brachial Pressure Index (ABI) were measured by automated arteriosclerosis detector. The changes of common carotid artery intima-media thickness (IMT) and parameters of the carotid artery elasticity in patients, including stiffness parameter (β), pressure-strain elastic modulus (Ep), arterial compliance (Ac), augmentation index (AI), and pulse wave velocity β (PWVβ) were detected by Echo-Tracking (ET) technique before and after 24 week treatment. In the meantime, levels of blood lipid, and liver and renal function were measured respectively.ResultsAfter 24 weeks, baPWV, IMT and parameters of the carotid artery elasticity (β, Ep, AI and PWVβ) were markedly decreased in intervention group compared with those of before treatment (P < 0.01), but the level of Ac was increased significantly (P < 0.01). And there were no significant differences compared with control group on the same period (P > 0.05).ConclusionIn this pilot study, it was demonstrated ET technology and automated arteriosclerosis detector could be used to evaluate carotid artery elasticity effectively, and the action of Shoushen granule on carotid atherosclerosis might be related to the regulation of carotid artery elasticity.

A high-sensitivity photonic crystal fiber long-period grating (PCF-LPG) methane sensor with cryptophane-A-6Me absorbed on a poly(acrylic acid)-carbon nanotubes/ polypropylene amine hydrochloride (PAA-CNTs/PAH) nanofilm was investigated. The sensing film was coated onto the internal surface of a photonic crystal fiber cladding air holes by an electrostatic self-assembly technique. Based on a finite element method and the coupled local-mode theory, the effects of the sensing film's refractive index (RI) and thickness on the resonant wavelength were theoretically and numerically analyzed. When the sensing film RI decreases from 1.55 to 1.53, and the thickness increases from 100 nm to 200 nm, the resonant wavelength has a blue shift. A higher RI sensitivity with 1.075 × 103 nm RIU-1 is observed for the film thickness of 200 nm. The PCF-LPG methane sensor was fabricated by a pressurized injection method. The sensing experimental result shows that the resonant wavelength of the transmission spectra has a blue shift when the methane concentration increases from 0.0% to 3.5% by volume. The sensor has a good sensitivity of 1.078 nm%-1 and a low detection limit of 0.18% for a film thickness of 210 nm.

Langerhans cell histiocytosis (LCH) is a rare disease of neoplastic proliferation of monocyte–macrophage system. Although LCH can affect almost any organ, solitary involvement of jugular foramen is extremely rare and can present a diagnostic dilemma because of its rarity at this location. Here, we present the case of an adult patient with LCH affecting the jugular foramen, and review the relevant literature.

By describing the technique of port connection and flow chart ofR/W operation between 24LC01, serial E2PROM, and EM78P447A, features of EM78P447 and its connection with I2C serial bus are introduced. In the end, the programe of writing operation is given.