[A Case of Synchronous Papillary Thyroid Cancer and Breast Ductal Cancer].

Occurrences of thyroid cancer and breast cancer metachronously or synchronously are common for women. Explanations for these associations include detection bias, shared hormonal risk factors, and genetic susceptibility, but the etiology behind specific associations is not elucidated well. The importance of the relationship between breast and thyroid cancer will continue to become evident and physicians should be aware of this association in caring for thyroid and breast cancer survivors. We report a case of synchronous papillary thyroid cancer and breast ductal cancer.

Comparison Between Cz-C3/C4 and C3-C4 Montages to Protect Against Peripheral Stimulation in Transcranial Facial Motor-Evoked Potential Monitoring.

INTRODUCTION: In facial motor-evoked potential monitoring, efforts to reduce peripheral stimulation are necessary because it can cause false-negatives. The effects of peripheral stimulation on Cz-C3/C4 and C3-C4 montages were compared. METHODS: Facial motor-evoked potentials were recorded from bilateral orbicularis oculi (Oculi) and oris (Oris) muscles. The double-train approach combining single-pulse and five-train pulse stimulation was used to determine the effect of peripheral stimulation. If the five-train pulse produced a significant waveform, it was defined as "total success." In total success cases, "true success" was defined as a case in which no waveform appeared after the single pulse at the threshold level of the five-train pulse. The total and true success rates and the threshold value of Oculi and Oris were compared between Cz-C3/C4 and C3-C4 montages. RESULTS: Thirty-six muscles each of Oculi and Oris of 18 patients were used for the analysis. True success was more likely to be obtained by the Cz-C3/C4 montage than the C3-C4 montage in Oculi (42% vs. 22%, p = 0.039). Both Oculi and Oris had higher thresholds to elicit facial motor-evoked potentials with the Cz-C3/C4 montage (Oculi: 101.7 vs. 71.4 mA, p = 0.038; Oris: 94.8 vs. 73.1 mA, p = 0.016). CONCLUSIONS: Cz-C3/4 montage is more effective at reducing peripheral stimulation compared with the C3-4 montage. This effect was primarily seen in the orbicularis oculi muscle. It should be noted that the Cz-C3/C4 montage has a higher threshold than the C3-C4 montage in facial muscles. In facial motor-evoked potential monitoring, the Cz-C3/C4 montage may be more suitable to eliminate peripheral stimulation.

Increase in terahertz-wave intensity in a magnetic field due to difference-frequency mixing by exciton excitation in a GaAs/AlAs multiple quantum well.

Magnetic fields can increase the intensity of terahertz (THz) waves due to changing the dipole moment direction using the Lorentz force. This study reports the increase in the THz-wave intensity generated by differential frequency mixing using commercial permanent magnets under exciton-excitation. While a weak magnetic field applied to a multiple quantum well increases the THz-wave intensity due to excitons, a strong field causes its decrease. According to the calculations, the increase is caused by the electron-hole separation due to the Lorentz force. Furthermore, the calculations suggest the importance of carrier acceleration to enhance the intensity. Importantly, the increase in the THz-wave intensity due to differential frequency mixing does not require a strong magnetic field and can be achieved with inexpensive commercially available magnets.

Effectiveness of frailty screening and perioperative team management of colectomy patients aged 80 years or more.

BACKGROUND: We aimed to clarify usefulness of the modified Frailty Index 11 (mFI-11) for assessing risk of postoperative complications (POCs) and effectiveness of perioperative management team (POMT) intervention for improving postoperative status of frail aged patients requiring colorectal cancer (CRC) surgery. METHODS: We compared, retrospectively, surgical outcomes among 151 consecutive CRC surgery patients aged ≥80 years. Patients were grouped by mFI-11 scores and by POMT intervention (vs. no POMT intervention). RESULTS: POCs were more prevalent, postoperative stays were longer, and discharge status was poorer among high-risk (mFI-11 ≥ 3/11) patients without POMT intervention than among low-risk (mFI-11 ≤ 2/11) patients (p = 0.04, p = 0.02, p < 0.01). Multiple POCs occurred less frequently and performance of activities of daily living was better for high-risk patients with (vs. those without) POMT intervention (p = 0.04, p = 0.03). CONCLUSION: POMT intervention appears beneficial for frail aged patients scheduled for CRC surgery.

Increase in terahertz-wave generation by difference frequency mixing by the overlap of exciton states in different GaAs/AlAs quantum wells and spectroscopic measurements.

Intense terahertz-wave emission in the higher frequency region can result in various applications such as terahertz spectroscopy and ultrafast data communication. In this study, an increase in terahertz waves by the overlap of exciton states in different quantum wells and spectroscopic demonstration are reported. The excitation energy dependence of signal intensity shows the effect of the overlap. The signals measured under the condition of square dependence of intensity on the excitation power indicate interference with the periods corresponding to the laser energy difference. Furthermore, the absorption coefficient of the transparent sheet is obtained at specific frequency. These results indicate that the generation of intense terahertz waves at various frequencies using excitons is possible and that difference frequency mixing is a useful terahertz-wave source.

Infrared photodetector sensitized by InAs quantum dots embedded near an Al0.3Ga0.7As/GaAs heterointerface.

Mid-infrared sensors detect infrared radiation emitted from objects, and are actually widely used for monitoring gases and moisture as well as for imaging objects at or above room temperature. Infrared photodetectors offer fast detection, but many devices cannot provide high responsivity at room temperature. Here we demonstrate infrared sensing with high responsivity at room temperature. The central part of our device is an Al0.3Ga0.7As/GaAs heterostructure containing InAs quantum-dot (QD) layer with a 10-nm-thick GaAs spacer. In this device, the electrons that have been accumulated at the heterointerface are transferred to the conduction band of the Al0.3Ga0.7As barrier by absorbing infrared photons and the following drift due to the electric field at the interface. These intraband transitions at the heterointerface are sensitized by the QDs, suggesting that the presence of the QDs increases the strength of the intraband transition near the heterointerface. The room-temperature responsivity spectrum exhibits several peaks in the mid-infrared wavelength region, corresponding to transitions from the InAs QD and wetting layer states as well as the transition from the quantized state of the triangular potential well at the two-dimensional heterointerface. We find that the responsivity is almost independent of the temperature and the maximum value at 295 K is 0.8 A/W at ~ 6.6 µm for a bias of 1 V, where the specific detectivity is [Formula: see text] cmHz1/2/W.

Determination of silicon wafer site flatness using dual heterodyne interferometers with sub-nanometer precision.

Precise measurement of wafer flatness with high sensitivity and high spatial resolution is essential to realize high yields in nano-scale lithography because the depth of focus in this technology is relatively small. We report on a highly precise site flatness measurement system that employs a pair of heterodyne interferometers and achieves sub-nanometer precision for polished 300-mm silicon wafers. The determined overall mean standard deviation for the site flatness front-surface least-squares fit range is 0.21 nm. Furthermore, this system allows us to obtain images of the wafer flatness via scanning with a high spatial resolution of approximately 12 µm. These results suggest that the heterodyne interferometer-based system is a suited candidate for use at the next-generation 16-nm half-pitch technology node.

Improving laser cooling efficiencies of Yb-doped yttrium aluminum garnet by utilizing non-resonant anti-Stokes emission at high temperatures.

Laser cooling in solids has been demonstrated, and cooling from room temperature to cryogenic temperatures has so far been the main focus of research. However, operation at high temperatures can be advantageous. We propose that laser cooling of Yb-doped yttrium aluminum garnet ceramic discs is enhanced above 300 K. Photoluminescence (PL) spectra is evidence that the phonon-assisted energy transfer from resonant states, which exhibit a narrow PL peak, to inhomogeneously distributed energy states becomes stronger at higher temperatures. This results in an enhanced non-resonant anti-Stokes PL at high temperatures. The ideal cooling efficiency determined from the PL spectrum at 470 K is 1.7 times higher than that at 300 K.

Adiabatic two-step photoexcitation effects in intermediate-band solar cells with quantum dot-in-well structure.

We studied the dynamics of electrons generated by two-step photoexcitation in an intermediate-band solar cell (IBSC) comprising InAs/GaAs/Al0.3Ga0.7As dot-in-well (DWELL) structure using time-resolved photocurrent (TRPC) measurement. The examined IBSC exhibited considerably slower photocurrent decay than a conventional InAs/GaAs quantum dot IBSC, which is due to the extraordinarily long-lived electrons in the DWELL. In order to retrieve the electron lifetime from the decay profile, we developed a model reproducing the observed decay and performed parameter fitting. The fitting results indicate that the electron lifetime in the DWELL is approximately 30 µs. In the two-colour excitation TRPC measurement, we found that an additional infrared (IR) light accelerates the photocurrent decay while the photocurrent increases by approximately 3%, because the additional IR light causes two-step photoexcitation of electrons in the DWELLs towards the conduction band. Furthermore, we demonstrated that the open-circuit voltage increases with increasing of the contribution of the second IR excitation process.

Increasing conversion efficiency of two-step photon up-conversion solar cell with a voltage booster hetero-interface.

Development of high-efficiency solar cells is one of the attractive challenges in renewable energy technologies. Photon up-conversion can reduce the transmission loss and is one of the promising concepts which improve conversion efficiency. Here we present an analysis of the conversion efficiency, which can be increased by up-conversion in a single-junction solar cell with a hetero-interface that boosts the output voltage. We confirm that an increase in the quasi-Fermi gap and substantial photocurrent generation result in a high conversion efficiency.

Two-step photon up-conversion solar cells.

Reducing the transmission loss for below-gap photons is a straightforward way to break the limit of the energy-conversion efficiency of solar cells (SCs). The up-conversion of below-gap photons is very promising for generating additional photocurrent. Here we propose a two-step photon up-conversion SC with a hetero-interface comprising different bandgaps of Al0.3Ga0.7As and GaAs. The below-gap photons for Al0.3Ga0.7As excite GaAs and generate electrons at the hetero-interface. The accumulated electrons at the hetero-interface are pumped upwards into the Al0.3Ga0.7As barrier by below-gap photons for GaAs. Efficient two-step photon up-conversion is achieved by introducing InAs quantum dots at the hetero-interface. We observe not only a dramatic increase in the additional photocurrent, which exceeds the reported values by approximately two orders of magnitude, but also an increase in the photovoltage. These results suggest that the two-step photon up-conversion SC has a high potential for implementation in the next-generation high-efficiency SCs.

Effects of non-exciton components excited by broadband pulses on quantum beats in a GaAs/AlAs multiple quantum well.

In this study, we report the effect of the excitation of non-exciton components caused by broadband pulses on quantum beat oscillation. Using a spectrally controlled pump pulse, a long-lived oscillation is clearly observed, and the pump-power dependence shows the suppression of the dephasing rate of the oscillation. Our results from incoherent carrier generation using a continuous wave laser demonstrate that the non-exciton components behaving as free carriers increase the oscillation dephasing rate.

[A Case of Cardiopulmonary Arrest due to Difficult Mask Ventilation and Difficult Laryngoscopy in the Ward after Operation: A Case Report].

A 77-year-old man with paroxysmal atrial fibrillation and hypertrophic obstructive cardiomyopathy was scheduled for cervical laminoplasty. He was predicted difficult mask ventilation combined with difficult laryn- goscopy (CICV) because of short thyromental distance. After induction of general anesthesia, we attempted tracheal intubation using McGRATHO and Gum-elastic Bougie and the intubation was successful. After opera- tion, in ward, atrial fibrillation occurred. Because anti- arrhythmic agents were not effective, cardioversion was planned. While under sedation, his breathing stopped. The attending physician could not ventilate with mask and intubate with Macintosh laryngoscope. The patient went into cardiopulmonary arrest After successful intubation using McGRATH? and Gum- elastic Bougie by anesthesiologist The attending physi- cian did not recognize CICV. We should convey infor- mation of CICV surely and perform education about difficult airway management.

[The Influence of Preoperative Oral Carbohydrate Administration on Perioperative Blood Sugar Levels and Patients' Satisfaction].

BACKGROUND: After introducing preoperative oral carbohydrate as a part of enhanced recovery after surgery (ERAS) protocols, we assessed the influence of carbohydrate administration on the perioperative blood sugar levels (BS), the variation of vital signs and patients' satisfaction. METHODS: After IRB's approval and obtaining patients' consent, patients were divided into two groups; taking carbohydrate (Group AW) or not (Group NAW). Anesthesia was induced and maintained with total intravenous anesthesia using propofol, remifentanil and rocuronium. We measured BS six times during perioperative period. We also compared blood pressures and heart rates during induction of anesthesia. Moreover, we carried out questionnaire surveys about degree of satisfaction for ERAS among patients and nurses. RESULTS: Heart rates were significantly higher in Group AW (P < 0.05), but there were no significant difference in blood pressures or BS between the groups. Patients in Group AW had more anxiety for surgeries (P = 0.003), but more than 85% of patients and nurses were satisfied with carbohydrates. CONCLUSIONS: The carbohydrate administration had little influence on the perioperative vital signs. However, we gained high reputations from patients and paramedics.

[Safety and economics of fondaparinux administration in the laparoscopic surgery].

BACKGROUND: The factor Xa inhibitor, fondaparinux was used for prevention of venous thromboembolism in the clinical setting. We evaluated the antithrombotic effect, complications and economic aspects of this agent in the patients undergoing laparoscopic surgery. METHODS: Forty one patients scheduled for laparoscopic abdominal surgery were divided into two groups. In group F (N = 33), patients received once-daily subcutaneous injection of fondaparinux (2.5 mg x day(-1)) for 4 postoperative days. In group E (N = 8), patients did not receive therapy. In group F, general anesthesia with transversus abdominis plane (TAP) block was administered during surgery, and general anesthesia with epidural anesthesia was performed in group E. We evaluated incidence of DVT (deep vein thrombosis), abnormal bleeding, other postoperative complications, and economic benefit to the hospital. RESULTS: In both groups, no patient developed DVT Abnormal bleeding was observed in 7 patients of group E. Postoperative complications and pain were not different between the two groups. The revenue in group F was 34,434 yen/patient lower than that of group E due to Japanease insulance system. CONCLUSIONS: No patients developed DVT and severe complications of fondaparinux after laparoscopic abdominal cancer surgery. However, revenue to the hospital decreased 34,434 yen/patient by use of analgestic method. We must consider cost-benefit in use of fondaparinux.

[Reliability of a less-invasive cardiac output monitor in the perioperative period of a patient with severe dilated cardiomyopathy].

Recently, various less-invasive cardiac output monitors are used for a variety of cases. We used FloTrac system for a patient with severe dilated cardiomyopathy (LVDd/Ds = 75/62 mm, EF = 22%) and recognized its limitation. A 52-year-old woman underwent left partial mastectomy. There were no significant events during the operation. In the ICU, she developed symptoms of low output state, but we could not detect any significant changes on Vigileo Monitor. Arterial pressure-based cardiac output (APCO) measurement with FloTrac is based on the patient's characteristics, blood pressure waveform and basic data stored in Vigileo Monitor. Its accuracy is worse with arterial wave artifact, compromise of the arterial catheter, aortic regurgitation, intense peripheral vasoconstriction, irregular pulse and severe cardiac hypofunction. Thus, its reliability is influenced by various conditions, especially in critically ill patients. FloTrac system is very useful for the management of cardiocirculatory dynamics, but we should be familiar with its limitations.

[Hypertrophic cardiomyopathy].

A 68-year-old woman with severe cardiac dysfunction due to dilated phase of hypertrophic cardiomyopathy was diagnosed with sigmoid cancer and scheduled for high anterior resection. Preoperative left ventricular ejection fraction (EF) was 16% by transthoracic echocardiography. After placement of an epidural catheter at the T12-L1 interspace, and artery catheters in the left radial artery for invasive blood pressure monitoring and in the right femoral artery for stand-by IABE general anesthesia was induced by midazolam, fentanyl and sevoflurane, and maintained with sevoflurane. Analgesia was obtained by epidural administration of 1% lidocaine and 0.2% ropivacaine. A central venous catheter was placed in the right internal jugular vein through which dobutamine was infused throughout the operation. Cardiac function monitored by transesophageal echocardiography showed EF of 9% just after insertion. After arbitrary administration of phenylephrine and landiolol, the operation and anesthesia were completed without serious problems. However, congestive heart failure worsened on postoperative day 2, and was improved by increasing dobutamine and by administration of milrinone.

Pseudoaneurysm of the mitral-aortic intervalvular fibrosa on a native aortic valve following infective endocarditis.

Pseudoaneurysm of the mitral-aortic intervalvular fibrosa (MAIVF) rarely forms on native aortic valve after infective endocarditis (IE). It is often fatal because of its rapid progress, high rates of rupture and recurrence, and worsening effects on the systemic condition. Echocardiography, especially transesophageal echocardiography, plays an important role in the diagnosis and assessment of this condition. We experienced a rare case of a patient with an unfortunate course following native aortic valve IE. After the patient had undergone surgical evacuation of a blood clot due to the rupturing of an embolomycotic cerebral aneurysm, a pseudoaneurysm of the MAIVF was found. Aortic valve replacement and pseudoaneurysm repair were performed 3 months after the neurosurgery. Echocardiographic still images were obtained during these two operations.

[Parental presence is a useful method for smooth induction of anesthesia in children: a postoperative questionnaire survey].

BACKGROUND: Parental presence during induction of anesthesia (PPIA) is widely practiced to prevent preoperative anxiety in children. However, some previous studies described parental presence is less effective than sedative premedication. The purpose of this investigation is to determine whether PPIA is not an effective prevention of preoperative anxiety using a postoperative questionnaire survey to parents. METHODS: PPIA was performed for 72 children (aged 1-15 years old) during one year. No patients received sedative premedication before surgery. We evaluated degree of anxiety before induction of anesthesia with four-point scale, 1: exciting and crying before entering surgical room, 2: exiting and crying on a surgical bed, 3: agitated, crying, not exciting, 4: calm. After surgery, we executed a questionnaire survey to parents concerning degree of anxiety and satisfaction. RESULTS: Ninty percent of parents accepted PPIA and all parents wanted PPIA next time if their children undergo surgery again. Younger age and frequency of surgery were associated with anxiety during induction in children (P<0.05). On the other hands, children above ten years of age did not want PPIA so much. CONCLUSIONS: PPIA has beneficial effects against preoperative anxiety in both children and parents.