On Efficient Range-Summability of IID Random Variables in Two or Higher Dimensions

d-dimensional (for d > 1) efficient range-summability (dD-ERS) of random variables (RVs) is a fundamental algorithmic problem that has applications to two important families of database problems, namely, fast approximate wavelet tracking (FAWT) on data streams and approximately answering range-sum queries over a data cube. Whether there are efficient solutions to the dD-ERS problem, or to the latter database problem, have been two long-standing open problems. Both are solved in this work. Specifically, we propose a novel solution framework to dD-ERS on RVs that have Gaussian or Poisson distribution. Our dD-ERS solutions are the first ones that have polylogarithmic time complexities. Furthermore, we develop a novel k-wise independence theory that allows our dD-ERS solutions to have both high computational efficiencies and strong provable independence guarantees. Finally, we show that under a sufficient and likely necessary condition, certain existing solutions for 1D-ERS can be generalized to higher dimensions

A Dyadic Simulation Approach to Efficient Range-Summability

Efficient range-summability (ERS) of a long list of random variables is a fundamental algorithmic problem that has applications to three important database applications, namely, data stream processing, space-efficient histogram maintenance (SEHM), and approximate nearest neighbor searches (ANNS). In this work, we propose a novel dyadic simulation framework and develop three novel ERS solutions, namely Gaussian-dyadic simulation tree (DST), Cauchy-DST and Random Walk-DST, using it. We also propose novel rejection sampling techniques to make these solutions computationally efficient. Furthermore, we develop a novel k-wise independence theory that allows our ERS solutions to have both high computational efficiencies and strong provable independence guarantees

Importance of the ammonia assimilation by Penicillium purpurogenum in amino derivative Monascus pigment, PP-V, production

A fungal strain, Penicillium purpurogenum IAM 15392, produced the azaphilone Monascus pigment homolog when cultured in a medium composed of soluble starch, ammonium nitrate, yeast extract, and citrate buffer, pH 5.0. One of the typical features of violet pigment PP-V [(10Z)-12- carboxyl-monascorubramine] is that pyranoid oxygen is replaced with nitrogen. In this study, we found that glutamine synthetase (glnB) and glutamate dehydrogenase (gdh1) genes were expressed in the culture conditions conducive to PP-V production. Gln and Glu both support PP-V biosynthesis, but PP-V biosynthesis was much more efficient with Gln. We determined that synthesis of Gln by glutamine synthetase from ammonium is important for PP-V production

Accuracy of Multilevel Registration in Image-Guided Pedicle Screw Insertion for Adolescent Idiopathic Scoliosis

This is a non-final version of an article published in final form in SPINE 35(3): 347-352, 2010.Study Design. Retrospective clinical study. Objective. To assess the accuracy of multilevel registration for skip pedicle screw placement during image-guided, computer-assisted spine surgery, in the setting of adolescent idiopathic scoliosis (AIS). Summary of Background Data. Computerized frameless stereotactic image-guidance has been used recently to improve pedicle screw placement accurately and safety during spine surgery. Because of possible intervertebral motion and usual difference in patients' position between preoperative imaging and surgery, the imaging model and the surgically exposed spine may be significantly discordant. Consequently, current protocols suggested separate registration of each spinal level (single-level registration) before respective pedicle screw placement, a time-consuming process. Moreover, although multilevel registration for lumbar spine has been reported, and that for thoracic spine has not. Methods. A total of 19 patients ( 1 male and 18 females; mean age, 13.9 years) with AIS who underwent multilevel registration for skip pedicle screw placement were included. Variables including surgical time, blood loss, preoperative and 2-year postoperative Cobb angle, correction rate, and postoperative screw position by computed tomography image were evaluated. Mean registration error after point merge and again after surface merge were recorded for each consecutive vertebra of each case. Results. Mean surgical time was 310 minutes ( range, 168-420 min). Mean blood loss 1138 g (range, 300-2300 g). Cobb angle before operation and at 2 years postoperation was 62.4 degrees (43 degrees-100 degrees) and 21.6 degrees (9 degrees-42 degrees), respectively. Mean correction rate 66.2% (39.7%-84.5%). Total 265 screws were inserted with computed tomography-based navigation system. Pedicle violation was observed in only 4 screws (1.5%). No neurovascular complication occurred. After point merge, average Mean registration error of all cases was 1.69 +/- 0.52 mm, and after surface merge was 0.51 +/- 0.16 mm. Conclusion. Multilevel registration may decrease operative time without compromising accuracy of pedicle screw placement afforded by this technique in the setting of AIS.http://journals.lww.com/spinejournal/pages/default.aspx | http://journals.lww.com/spinejournal/pages/default.aspxArticleSPINE. 35(3):347-352 (2010)journal articl

Space- and Computationally-Efficient Set Reconciliation via Parity Bitmap Sketch (PBS)

Set reconciliation is a fundamental algorithmic problem that arises in many networking, system, and database applications. In this problem, two large sets A and B of objects (bitcoins, files, records, etc.) are stored respectively at two different network-connected hosts, which we name Alice and Bob respectively. Alice and Bob communicate with each other to learn $A\Delta B$, the difference between A and B, and as a result the reconciled set $A\bigcup B$. Current set reconciliation schemes are based on either Invertible Bloom Filters (IBF) or Error-Correction Codes (ECC). The former has a low computational complexity of O(d), where d is the cardinality of $A\Delta B$, but has a high communication overhead that is several times larger than the theoretical minimum. The latter has a low communication overhead close to the theoretical minimum, but has a much higher computational complexity of $O(d^2)$. In this work, we propose Parity Bitmap Sketch (PBS), an ECC- based set reconciliation scheme that gets the better of both worlds: PBS has both a low computational complexity of O(d) just like IBF-based solutions and a low communication overhead of roughly twice the theoretical minimum. A separate contribution of this work is a novel rigorous analytical framework that can be used for the precise calculation of various performance metrics and for the near-optimal parameter tuning of PBS

Computer-assisted hemivertebral resection for congenital spinal deformity

No studies have reported on osteotomies utilizing a navigation system in congenital scoliosis surgery. This study aimed to evaluate the surgical outcomes of eight patients with congenital scoliosis or kyphoscoliosis due to hemivertebrae treated by computer-assisted hemivertebral resection using only a posterior approach. Eight consecutive patients (two scoliotics and six kyphoscoliotics) managed by computer-assisted hemivertebral resection using only a posterior approach with transpedicular instrumentation were investigated retrospectively. A CT-based navigation system was used to confirm the positions of the vertebra, spinal cord and aorta in real-time when we inserted a pedicle screw and conducted the osteotomy. The mean patient age at surgery was 18 years (range 11-41 years). The mean follow-up was 46 months (range 18-84 months). Before surgery, the mean kyphotic curve was 55.8A degrees (range 26-83A degrees), and the mean scoliotic curve was 50.0A degrees (range 36-62A degrees). At the final follow-up period, the curves averaged 23.2A degrees (range 15-40A degrees) and 31.6A degrees (range 21-44A degrees), respectively, yielding kyphotic angle corrections of 32.7A degrees (range 11-58A degrees) and Cobb angle correction rates of 36.8% (range 24.1-48.3%). A total of 72 pedicle screws were inserted with the navigation system, and two screws revealed a perforating pedicle. No neurovascular complications occurred. The perforation rate was 2.8%. Hemivertebral resection via a single posterior approach is less invasive than combined anterior and posterior approaches; however, this procedure increases the risk of spinal cord and vascular injuries. Computer-assisted hemivertebral resection enables safe and accurate performance of a hemivertebral resection via a single posterior approach.ArticleJOURNAL OF ORTHOPAEDIC SCIENCE. 16(5):503-509 (2011)journal articl

Pancreatic β Cell–specific Expression of Thioredoxin, an Antioxidative and Antiapoptotic Protein, Prevents Autoimmune and Streptozotocin-induced Diabetes

The cytotoxicity of reactive oxygen intermediates (ROIs) has been implicated in the destruction of pancreatic β cells in insulin-dependent diabetes mellitus (IDDM). Thioredoxin (TRX), a redox (reduction/oxidation)-active protein, has recently been shown to protect cells from oxidative stress and apoptosis. To elucidate the roles of oxidative stress in the development of autoimmune diabetes in vivo, we produced nonobese diabetic transgenic mice that overexpress TRX in their pancreatic β cells. In these transgenic mice, the incidence of diabetes was markedly reduced, whereas the development of insulitis was not prevented. Moreover, induction of diabetes by streptozotocin, an ROI-generating agent, was also attenuated by TRX overexpression in β cells. This is the first direct demonstration that an antioxidative and antiapoptotic protein protects β cells in vivo against both autoimmune and drug-induced diabetes. Our results strongly suggest that oxidative stress plays an essential role in the destruction of β cells by infiltrating inflammatory cells in IDDM

Evaluation of clinical results and quality of life after surgical reconstruction for rheumatoid cervical spine

BACKGROUND CONTEXT: The EuroQol (EQ-5D) is a widely used comprehensive measure of health-related quality of life. There has been no study that has evaluated the health-related quality of life before and after the surgical reconstruction of rheumatoid arthritis (RA) cervical spine lesions using EQ-5D. PURPOSE: The present study aimed to evaluate the improvement of quality of life before and after surgical reconstruction of rheumatoid cervical spine using EQ-5D, and the surgical outcomes of cervical spine affected by RA. STUDY DESIGN: A retrospective study of the patients who underwent surgical reconstruction of cervical disorders in RA. PATIENT SAMPLE: Twenty-five patients (seven men, 18 women, mean age 62.2 years) who underwent surgical reconstruction of cervical disorders in RA were enrolled. OUTCOME MEASURES: Japanese Orthopaedic Association (JOA) score and EQ-5D. METHODS: Clinical symptoms were evaluated before surgery and at 2 years after surgery by measuring the JOA score. We also investigated health-related quality of life before surgery and outcome at 2 years after surgery using the EQ-5D questionnaire. RESULTS: Mean observation period was 46.3 months. Mean JOA score significantly improved from 9.1 +/- 4.5 points before surgery to 12.4 +/- 2.8 at the 2 years after surgery (p=.0001). All the EQ-5D data were improved at the 2 years after surgery, compared with the data before surgery; especially, pain (p=.005), usual activity (p=.005), mobility (p=.008), and anxiety/depression (p=.02) were significantly improved. Utility weight was 0.37 +/- 0.27 before surgery and 0.56 +/- 0.26 at the 2 years after surgery, showing significant improvement at the 2 years after surgery compared to before surgery (p=.002). CONCLUSIONS: The surgical reconstruction of rheumatoid cervical spine has been demonstrated to improve patients' health-related quality of life.ArticleSPINE JOURNAL. 13(4):391-396 (2013)journal articl