Improvements In Microarchitecture Research Articles

Efficient Data Supply for Parallel Heterogeneous Architectures

Decoupling techniques have been proposed to reduce the amount of memory latency exposed to high-performance accelerators as they fetch data. Although decoupled access-execute (DAE) and more recent decoupled data supply approaches offer promising single-threaded performance improvements, little work has considered how to extend them into parallel scenarios. This article explores the opportunities and challenges of designing parallel, high-performance, resource-efficient decoupled data supply systems. We propose M ercury , a parallel decoupled data supply system that utilizes thread-level parallelism for high-throughput data supply with good portability attributes. Additionally, we introduce some microarchitectural improvements for data supply units to efficiently handle long-latency indirect loads.

Towards hardware embedded virtualization technology

Embedded virtualization possesses inherent challenges which differentiate the domain from traditional virtualization application fields such as server and desktop computing. Standard software virtualization solutions have a negative impact, not only on memory footprint and performance, but also on determinism and interrupt latency which are critical for the embedded real-time domain. Thus, efficient embedded virtualization requires domain-specific software and hardware support. This paper presents work in progress results of hardware-based Hypervisor implementation. The use cases of embedded virtualization are analyzed, justifying the reasoning for hardware-supported virtualization. Architectural and micro-architectural improvements to an ARM v5TE processor are described, demonstrating the performance advantages, and compared against ARM Virtualization Extensions, identifying respective vulnerabilities and providing alternative solutions which enable higher flexibility, minimizing virtualization costs. The research roadmap towards a hardware-complete Hypervisor, based on the presented results, is described.

Effects of total lignans from Eucommia ulmoides barks prevent bone loss in vivo and in vitro

Ethnopharmacological relevanceThe present study systematically investigate the in vivo and in vitro effect of total lignans (TL) extracted from Eucommia ulmoides Oliv. barks on bone formation using ovariectomy rat model and primary cultures of rat osteoblasts. Materials and methodsEighty 3-month-old female Sprague-Dawley rats were used and randomly assigned into sham-operated group (SHAM) and five ovariectomy (OVX) subgroups, i.e. OVX with vehicle (OVX); OVX with 17α-ethinylestradiol (E2, 25μg/kg/day); OVX with TL of graded doses (20, 40, or 80mg/kg/day). The treatment began 4 weeks after the surgery and lasted for 16 weeks. in vitro experiments were performed to determine the potential mechanisms of the anti-osteoporotic effect of TL. ResultsTreatment with TL significantly prevent OVX-induced decrease in biomechanical quality of femur such as maximum stress and Young׳s modulus. The mechanical changes were associated with the prevention of a further BMD decrease or even with some improvements in microarchitecture. TL inhibited BMD decrease in the femur caused by OVX, which was accompanied by a significant decrease in skeletal remodeling, as was evidenced by the decreased levels of the bone turnover markers. μCT analysis of the femoral metaphysis showed how to prevent the deterioration of trabecular microarchitecture. TL induced primary osteoblastic cell proliferation and differentiation, inhibition of osteoclastogenesis through an increase in osteoprotegrin (OPG) and a decrease in NF-κB ligand (RANKL) expression in vitro. ConclusionsWe concluded that TL treatment can effectively suppress the loss of bone mass induced by OVX and in vitro evidence suggests this could be through actions on both osteoblasts and osteoclasts.

Effect of Total Glycosides from Eucommia ulmoides Seed on Bone Microarchitecture in Rats

Du-Zhong is one of the most important tonic herbs in traditional Chinese medicine for the treatment of bone fractures and other bone diseases. The present study examined whether Du-Zhong seed extract named total glycosides from Eucommia ulmoides seed (TGEUS) could display an increased effect on bone density and bone strength of the femur in rats. Sprague-Dawley rats were used and randomly assigned to the normal group and the TGEUS group (400 mg/kg body weight/day). Daily oral administration of TGEUS was found to increase significantly the biomechanical quality of the femur. The mechanical changes were associated with a bone mineral density (BMD) increase or even with some improvements in microarchitecture. Micro-CT analysis of the distal femur showed that TGEUS significantly increased the bone volume/tissue volume (BV/TV), connectivity density (Conn.D), trabecular number (Tb.N) and trabecular thickness (Tb.Th), and decreased trabecular separation (Tb.Sp) and the structure model index (SMI) in normal rats. To conclude, TGEUS taken orally increased bone density and altered bone histomorphology, suggesting that TGEUS might be a potential alternative medicine for the treatment of postmenopausal osteoporosis.

Telmisartan alleviates rosiglitazone-induced bone loss in ovariectomized spontaneous hypertensive rats

In the present study, we systematically examined telmisartan, an angiotensin AT 1 receptor antagonist, on rosiglitazone-induced bone loss in ovariectomized spontaneously hypertensive rats. Telmisartan (5 mg/kg/d, 90 days) was found to be able to significantly alleviate rosiglitazone (10 mg/kg/d, 90 days)-induced decrease in BMD of femur and lumbar vertebrae. The BMD changes were associated with positive biomechanical changes of lumbar vertebrae, improvements in microarchitecture of tibial metaphysic and normalized serum osteocalcin (OC) levels and urinary deoxypyridinoline/creatinine (DPD/Cr) ratio. MicroCT analysis of the tibial metaphysis showed that telmisartan significantly prevented the decreases in bone volume/tissue volume (BV/TV), connect density (Conn. D.), trabecular number (Tb. N.) and trabecular thickness (Tb. Th.), and increase in trabecular separation (Tb. Sp.) induced by rosiglitazone. Histomorphometric analysis also showed that telmisartan had protective effects on rosiglitazone-reduced bone formation indices such as histomorphometric bone volume fraction (BV/TV-Histo), mineralizing surface/bone surface (MS/BS), mineral apposition rate (MAR) and bone formation rate (BFR/BS). Our study clearly showed that telmisartan alleviated rosiglitazone-induced bone loss in ovariectomized spontaneous hypertensive rats. The relief of bone loss provides a possible therapeutic application of telmisartan with rosiglitazone for the treatment of elderly women patients afflicted with metabolic syndrome.

Du-Zhong ( Eucommia ulmoides Oliv.) cortex extract prevent OVX-induced osteoporosis in rats

Du-Zhong, rich in polyphenolic compounds such as lignans, phenolic acid, and flavonoids, is a kidney-tonifying herbal medicine with a long history of safe use for treatment of bone fractures and joint diseases in China. In the present study, we examined whether Du-Zhong cortex extract (DZCE) with graded doses exerted its preventive effects on estrogen deficiency-induced osteoporosis. Eighty 3-month-old female Sprague–Dawley rats were used and randomly assigned into sham-operated group (Sham) and five ovariectomy (OVX) subgroups, i.e. OVX with vehicle (OVX); OVX with 17α-ethinylestradiol (E 2, 25 μg/kg/day); OVX with DZCE of graded doses (100, 300, or 500 mg/kg/day). Daily oral administration of DZCE or E 2 started on week 4 after OVX for 16 weeks. Treatment with DZCE at higher doses (300 or 500 mg/kg/day) was found to be able to significantly prevent OVX-induced decrease in biomechanical quality of femur such as maximum stress and Young's modulus. The mechanical changes were associated with the prevention of a further bone mineral density (BMD) decrease or even with some improvements in microarchitecture. DZCE dose-dependently inhibited total BMD decrease in the femur caused by OVX, which was accompanied by a significant decrease in skeletal remodeling, as was evidenced by the decreased levels of the bone turnover markers osteocalcin (OC), alkaline phosphatese (ALP), deoxypyridinoline (DPD), and urinary Ca and P excretions. μCT analysis of the femoral metaphysis showed that DZCE at the highest doses (500 mg/kg/day) significantly prevents decrease in bone volume/tissue volume (BV/TV), connect density (Conn.D), trabecula number (Tb.N) and trabecula thickness (Tb.Th), and increase in trabecula separation (Tb.Sp) and structure model index (SMI) in OVX rats. We conclude that 16 weeks of DZCE treatment improves bone biomechanical quality through modifications of BMD, and trabecular microarchitecture without hyperplastic effect on uterus, and it might be a potential alternative medicine for treatment of postmenopausal osteoporosis.

Decisive aspects in the evolution of microprocessors

The incessant market demand for higher and higher processor performance called for a continuous increase of clock frequencies as well as an impressive evolution of the microarchitecture. In this paper, we focus on the latter, highlighting major microarchitectural improvements that were introduced to more effectively utilize instruction level parallelism (ILP) in commercial performance-oriented microprocessors. We will show that designers increased the throughput of the microarchitecture at the ILP level basically by subsequently introducing temporal, issue, and intrainstruction parallelism in such a way that exploiting parallelism along one dimension compelled to introduce parallelism along a new dimension as well to further increase performance. In addition, each basic technique used to implement parallel operation along a certain dimension inevitably caused processing bottlenecks in the microarchitecture, whose elimination gave birth to the introduction of innovative auxiliary techniques. On the other hand, the auxiliary techniques applied allow the basic technique of parallel operation to reach its limits, evoking the debut of a new dimension of parallel operation in the microarchitecture. The sequence of basic and auxiliary techniques coined to increase the efficiency of microarchitectures constitutes a fascinating framework for the evolution of microarchitectures, as presented in our paper.

Custom circuit design as a driver of microprocessor performance

This paper presents a survey of some of the most aggressive custom designs for CMOS processor products and prototypes in IBM. We argue that microprocessor performance growth, which has traditionally been driven primarily by CMOS technology and microarchitectural improvements, can receive a substantial contribution from improvements in circuit design and physical organization. We predict that in future microprocessor designs the floorplan and wire plan will be as important as the microarchitecture, more control logic will be structured and become indistinguishable from dataflow elements, and more circuits will be designed and analyzed at the level of single transistors and wires.