Spread spectrum mobile communication experiment using ETS-V satellite

The spread spectrum technique is attractive for application to mobile satellite communications, because of its random access capability, immunity to inter-system interference, and robustness to overloading. A novel direct sequence spread spectrum communication equipment is developed for land mobile satellite applications. The equipment is developed based on a matched filter technique to improve the initial acquisition performance. The data rate is 2.4 kilobits per sec. and the PN clock rate is 2.4552 mega-Hz. This equipment also has a function of measuring the multipath delay profile of land mobile satellite channel, making use of a correlation property of a PN code. This paper gives an outline of the equipment and the field test results with ETS-V satellite

Paleomagnetic Studies on Miocene Sequences of Hokutan and Tottori Groups in Southwest Japan: Implications for Middle Miocene Rotational Movement of Southwest Japan Block Associated with the Japan Sea Opening

Miocene sequences composed of volcanic rocks and overlying marine sediments distributing at the Japan Sea side of Southwest Japan have been considered to form related to the rifting and subsequent spreading of the Japan Sea back-arc basin in Miocene time. We performed paleomagnetic investigations on the sequences in the eastern San’in district, the Hokutan and Tottori Groups. Paleomagnetic analyses on samples from 33 sites indicated that characteristic magnetic components from five sites of volcanic rocks in the Hokutan Group and from four sites of marine sediments in the Tottori Group were regarded as primary components. An obtained paleomagnetic direction of the volcanic rocks has an easterly deflected declination (D = 23.9° ± 20.2°), while that of the marine sediments shows no significant deflection in declination (D = 17.8° ± 19.1°). Through the comparison with paleomagnetic data from the Miocene sequences in Southwest Japan, it is suggested that magnetic polarities of the volcanic and sedimentary sequences are assigned to C5Cn and C5Br-C5Bn, respectively, and that the eastern San’in district suffered a clockwise rotation of 24° at around 16 Ma after the early Miocene volcanic activity and before the middle Miocene marine transgression in the whole clockwise rotation process of Southwest Japan related to the Japan Sea opening

Accuracy of Acetabular Cup Implantation, as a Function of Body Mass Index and Soft-tissue Thickness, with a Mechanical Intraoperative Support Device: A Retrospective Observational Study

HipCOMPASS, a mechanical intraoperative support device used in total hip arthroplasty (THA), improves the cup-alignment accuracy. However, the alignment accuracy achieved by HipCOMPASS has not been specifically examined in obese patients. In this study, we retrospectively evaluated the relation between alignment accuracy and several obesity-related parameters in 448 consecutive patients who underwent primary THA using HipCOMPASS. We used computed tomography (CT) to measure the preoperative soft-tissue thickness of the anterior-superior iliac spine (ASIS) and pubic symphysis and the differences between preoperative and postoperative cup angle based on the cup-alignment error. We found significant correlations between the absolute value of radiographic anteversion difference and body mass index (r = 0.205), ASIS thickness (r = 0.419), and pubic symphysis thickness (r = 0.434). The absolute value of radiographic inclination difference was significantly correlated with ASIS (r = 0.257) and pubic symphysis thickness (r = 0.202). The receiver operating characteristic curve showed a pubic symphysis thickness of 37.2 mm for a ≥ 5° implantation error in both radiographic inclination and anteversion simultaneously. The cup-alignment error for HipCOMPASS was large in patients whose pubic symphysis thickness was ≥ 37.2 mm on preoperative CT. Our results indicate that methods other than HipCOMPASS, including computed tomography-based navigation systems, might be preferable in obese patients

Multidisciplinary Approach to Reduce Postoperative Complications and Improve the Activity of Patients with Hip Fracture: A 24-month Follow-up Survey

Multidisciplinary approaches such as fracture liaison services (FLS) have been introduced in some countries to reduce medical complications and secondary fractures in patients with fragility hip fracture. We aimed to investigate outcomes in patients with fragility hip fracture following the introduction of FLS. Patients > 50 years old who experienced fragility hip fractures between January 1, 2015 and December 31, 2017 were enrolled, and divided into a control group (without FLS; 94 patients) and FLS group (373 patients). We found that the time from injury to surgery decreased significantly from 2.42 to 1.83 days (p = 0.003), the proportion of patients who underwent surgery within 36 h of injury increased significantly (p = 0.014), and the number of cases with complications after admission decreased significantly (p = 0.004) in the FLS group. Patients with a Barthel index ≥ 80 were more common in the FLS than the control group at 6 , 12, and 24 months following injury (p = 0.046 , 0.018, and 0.048, respectively). Multiple logistic regression analysis revealed the factors associated with postoperative complications and death within 12 or 24 months after injury. Our results indicate that FLS contributed to earlier recovery, rehabilitation following surgery and rehabilitation of medical complications following admission; improved patient activity; and decreased secondary hip fractures

Weighted Matching Markets with Budget Constraints

We investigate markets with a set of students on one side and a set of colleges on the other. A student and college can be linked by a weighted contract that defines the student's wage, while a college's budget for hiring students is limited. Stability is a crucial requirement for matching mechanisms to be applied in the real world. A standard stability requirement is coalitional stability, i.e., no pair of a college and group of students has any incentive to deviate. We find that a coalitionally stable matching is not guaranteed to exist, verifying the coalitional stability for a given matching is coNP-complete, and the problem of finding whether a coalitionally stable matching exists in a given market, is Sigma(P)(2)-complete: NPNP -complete. Other negative results also hold when blocking coalitions contain at most two students and one college. Given these computational hardness results, we pursue a weaker stability requirement called pairwise stability, where no pair of a college and single student has an incentive to deviate. Unfortunately, a pairwise stable matching is not guaranteed to exist either. Thus, we consider a restricted market called a typed weighted market, in which students are partitioned into types that induce their possible wages. We then design a strategy-proof and Pareto efficient mechanism that works in polynomial-time for computing a pairwise stable matching in typed weighted markets

Cloning of an isoform of mouse TGF-β type II receptor gene

AbstractA variant of transforming growth factor-β type II receptor (TGF-βRII) cDNA was isolated from a mouse brain cDNA library. The predicted receptor is identical to previously reported mouse TGF-βRII except that the isoform has an insertion sequence of 25 amino acids in the predicted ligand-binding domain. By the use of reverse transcription-polymerase chain reaction (RT-PCR), transcripts for both isoforms were detected in all tissues and developing embryos examined. The isoform transiently expressed in COS cells showed a similar ligand-binding specificity to authentic TGF-βRII. These results suggest that the mouse TGF-βRII gene generates multiple isoforms, possibly by alternative splicing, as reported for activin type IIB receptor; and an isoform which has the extra sequence in the ligand-binding domain is also involved in the TGF-β signal transduction