bluuebunny/crossref_metadata_2025 huggingface dataset:
The Influence of Protected Passive Mobilization on the Healing of Flexor Tendons: A Biochemical and Microangiography Study
Authors: Gelberman R. H. , Amifl D. , Gonsalves M , Woo S. , Akeson W. H.
Published: March 2006

The purpose of this investigation was to determine the effects of protected passive mobilization on the repair processes of healing flexor tendons. The total DNA content of the healing tendon and tendon sheath was correlated with their vascularity over a twelve week period. A gradually increasing range of passive motion between the 21st and 84th days after operation was associated with reorientation of the blood vessels to a more normal pattern, a steady increase in sheath and repair site cellularity compared with the immobilized and control tendons. The altered vascularity reflected a stimulation of tendon scar remodeling, and the increased DNA signified an acceleration in tendon maturation.
Flexor Tendon Excursions in “No-Man's Land”
Authors: Mcgrouther D. A. , Ahmed M. R.
Published: March 2006

The excursions of the digital flexor tendons have been measured relative to the sheath and to one another at a point in no-man's land over the proximal phalanx, in fresh cadavers. Passive metacarpo-phalangeal joint movement produces no relative motion. Distal interphalangeal joint motion produces excursion of Flexor Digitorum Profundus on Flexor Digitorum Superficialis (a mean of 1 mm for ten degrees of flexion in the index finger). Proximal interphalangeal joint motion produces excursion of the Flexor Digitorum Superficialis and Flexor Digitorum Profundus together relative to the sheath (1.3 mm for ten degrees of joint flexion in the index finger).

The significance of these measurements is discussed in relation to the exploration of tendon injuries, the mechanism of failure after tendon repair, dynamic mobilisation and the anatomy of no-man's land.
Tenography in de Quervains Disease
Authors: Engel J. , Luboshitz S. , Israeli A. , Ganel A.
Published: March 2006

This paper describes our diagnostic method, which enables an early and immediate differentiation between those patients who could benefit from a single or several local corticosteroid injections, and those who will probably require surgery. The authors have no intention of advocating a preferred treatment, but try to predict the outcome of the various modes of therapy.
Metacarpal Reconstruction in Compound Contaminated Injuries of the Hand
Authors: Chait L. A. , Cort A. , Braun S.
Published: March 2006

The use of an external distraction fixation apparatus in severe compound contaminated injuries of the hand with avulsed segments of metacarpals is described. The method has the advantages of stabilizing bony fragments, maintaining hand length and allowing early access for dressings until reconstruction with a bone graft can be undertaken.
Carpal Tunnel Syndrome Caused by a Simple Ganglion
Authors: Harvey F. J. , Bosanquet J. S.
Published: March 2006

The compression of peripheral nerves by simple ganglia is a well recognized and documented clinical entity. It has been reported where ganglia have been associated with the ankle, knee and elbow joints (D. M. Brooks, 1952). It is probably best known in compression of the deep branch of the ulnar nerve in the wrist, first described by Seddon (Seddon H. J. 1952). Median nerve compression at the wrist, however, that causes a carpal tunnel syndrome would appear to be well recognized but poorly documented. Brooks (1952) described a case and until now, no others have been recorded in the literature.

This case report describes such median nerve involvement with some interesting features.
Simultaneous Dislocation of the Interphalangeal and Metacarpo-Phalangeal Joints in a Thumb
Authors: Cleak D. K.
Published: March 2006

Dislocation of more than one joint in a digit is a rare injury. Although several case studies have appeared describing multiple interphalangeal dislocations in fingers (Ikpeme, 1977; Nathan, 1973 and Weseley, 1978), no report of interphalangeal and metacarpo-phalangeal dislocations in the same thumb has been published.
Some Methods for Bone Fixation for Digital Replantation
Authors: Yamano Y. , Matsuda H. , Nakashima K. , Shimazu A.
Published: March 2006

Solid bone fixation constitutes one of the important factors in obtaining good function after replantation of amputated digits. Comparison has been made of various methods of bone fixation including a newly designed ceramic intramedullary screw which we have found useful for cases of amputation of a middle or proximal phalanx around its middle.
Compression-Arthrodesis of Finger Joints using Kirschner Wires and Cerclage
Authors: Høgh J. , Jensen P. Ø.
Published: March 2006

A retrospective series of forty-three finger joint arthrodesis is presented. The failure rate was seven per cent. A new method of introducing a cerclage wire into bone is demonstrated. Septic arthritis of finger joints is considered to be an indication for acute arthrodesis.
Clear Cell Sarcoma of the Hand
Authors: Andrew T. A.
Published: March 2006

A case of clear cell sarcoma of the extensor tendons of the hand is reported. This rare tumour has never been recorded at this site before. The clinical presentation, differential diagnosis, pathological features and treatment are discussed, and the importance of distinguishing simple ganglion from more serious pathology is stressed.
Arthrodesis of The Wrist in Rheumatoid Disease
Authors: Papaioannou T. , Dickson R. A.
Published: March 2006

Twelve cases of wrist fusion for rheumatoid disease have been assessed pre and postoperatively in terms of symptoms, function, union, and complications. Improvement in hand function can be attributed to the provision of a painless stable wrist, and fusion in the straight position is in no way detrimental to personal hygiene. Delayed wound healing and pin migration are not uncommon complications but do not affect the end-results, which is radiological union from third metacarpal to radius—a definitive situation.
Thermographic Diagnosis of Glomus Tumour
Authors: Corrado E. M. , Passaretti U. , Messore L. , Lanza F.
Published: March 2006

We will describe the advantages offered by tele-thermographic test of glomus tumour localized in the hand. Such advantages are the simplicity and absolute safety of the test and the possibility of obtaining useful information on the site and size of the neoplasm, permitting a correct diagnosis even if the characteristic signs are lacking. The test, moreover, can be carried out on an out-patient basis.

We will present some of the cases in which dynamic thermography permitted us to confirm the clinical diagnosis of glomus tumour.
Bilateral Carpal Tunnel Syndrome Associated with Unilateral Duplication of the Flexor Digitorum Superficialis Muscle: A Case Report
Authors: Gleason T. F. , Abraham E.
Published: March 2006

A middle aged patient with adult onset of bilateral carpal tunnel syndrome was found to have a unilateral duplication of the flexor digitorum superficialis muscle. The role of this rare accessory muscle in causing the syndrome is questioned.
Familial Trigger Thumb in Children
Authors: Van Genechten F.
Published: March 2006

Trigger thumbs were found in six members of the same family. Aetiology and treatment is discussed on the basis of the observed and reported anatomy.
Trigger Wrist Due to Anomalous Flexor Digitorum Profundus Muscle in Association with Fibroma of Tendon Sheath
Authors: Kernohan J. G. , Benjamin A. , Simpson D.
Published: March 2006

A description is given of an anomalous muscle arising from the flexor digitorum profundus tendon distal to the transverse carpal ligament, associated with a fibroma, which presented as trigger wrist.
Habitual Anterior Subluxation of the Head of the ULNA Treated by Baldwin's Operation. A Case Report
Authors: Thomas T. L. , Matthewson M. H.
Published: March 2006

A case of habitual anterior subluxation of the ulna at the inferior radio-ulnar joint is reported. The subluxation presented with signs and symptoms of both ulnar and median neuritis. There was no past history of trauma. Baldwin's procedure was carried out, stabilising the distal radio-ulnar joint and relieving all symptoms of nerve compression. The use of Baldwin's procedure to correct this condition has not previously been described.
Spontaneous Rupture of Flexor Tendons of a Little Finger Due to Projection of the Hook of the Hamate. A Case Report
Authors: Okuhara T. , Matsui T. , Sugimoto Y.
Published: March 2006

A case of spontaneous rupture of the flexor tendons of a little finger due to projection of the hook of the hamate is reported. The projection seemed to be caused from Colles fracture ten years ago. A satisfactory result was obtained by free tendon grafting.
Lunato-Triquetral Fusion and Associated Spinal Abnormality
Authors: Thakkar D. H.
Published: March 2006

Lunato-triquetral fusion is a rare congenital anomaly. Its association with skeletal dysplasias, tarsal coalitions and synostotic states in the upper limbs and other parts of the body is well established. There is no mention in the English literature about its association with congenital spinal abnormalities and secondary osteoarthrosis in the wrist and two such cases are now described.

Both cases presented with symptoms in the dominant hand and had symptoms of backache in the past. Their clinical course and X-ray findings are described.
Giant Cell Tumour of Metacarpal in a Child of Unusual Site and Age
Authors: Minguella J.
Published: March 2006

The opportunity of treating a giant cell tumour in a metacarpal of a six year old girl prompted the revision of the literature on this subject, verifying the extraordinary rarity of this kind of tumour in the bones of the hand and in children. The affected bone was excised and a metatarsal of the foot of the same girl transplanted in its place.
The Table top Test
Authors: Hueston J. T.
Published: March 2006

A simple test is described for the selection of patients with Dupuytren's Contracture, for operation.
The Microanatomy of Dupuytren's Contracture
Authors: Mcgrouther D. A.
Published: March 2006

The palmar fascial ligaments have been examined by microdissection using an operating microscope in fresh and preserved cadaveric hands. The palmar fascia is seen to be a precise three dimensional system of skin ligaments having discreet transverse, longitudinal and vertical fibre systems. In the normal hand there is relative motion between the ligament systems on movement. The longitudinal fibres provide a system of skin anchorage which operates irrespective of the position of the underlying joints and acts particularly to resist shearing forces in gripping.

The distribution of the lesions of Dupuytren's Disease has been recorded in a series of clinical cases; nodules, skin pits, distortion of the palmar creases, cords and joint contractures, and the pathogenesis of the disease is related to the anatomy of the palmar ligaments.

The disease is described as a process of contracture along anatomical pathways.

A hypothesis for the development of Dupuytren's Disease is presented whereby the loss of normal motion between palmar fascial ligaments gives rise on use of the hand to stress concentrations which stimulate fibrous tissue deposition and contracture.
Dupuytren's Contracture: Morphological and Biochemical Changes in Palmar Aponeurosis
Authors: Hamamoto H. , Ueba Y. , Sudo Y. , Sanada H. , Yamamuro T. , Takeda T.
Published: March 2006

The palmar aponeurosis removed from ten patients with Dupuytren's contracture was studied using morphological and biochemical approaches. The histological characteristic of Dupuytren's contracture is the presence of numerous nodules among the lamellar structures of the collagen fibres. In the nodules, there are many active fibroblasts which are surrounded by immature fibres and metachromatic substances demonstrated by toluidine blue staining. Ultrastructurally, the active fibroblasts have the characteristics of myofibroblasts, as previously reported by Dr. Gabbiani. We found that some fibroblasts have intracellular collagen fibrils in the cytoplasm.

When assayed by Siegel and Martin's method, lysyl oxidase activity of the palmar aponeurosis was significantly higher in Dupuytren's contracture than in normal hands. Biochemical studies such as electrophoretic analysis of mucopolysaccharides, determination of uronic acid and collagen contents were undertaken to compare the aponeurosis of Dupuytren's contracture with normal cases. The uronic acid contents were higher in Dupuytren's contracture than in the controls. However, no difference between the two groups was found in the collagen contents and in the composition of the mucopolysaccharides.

These characteristic features; existence of myofibroblasts and intracellular collagen fibrils and increase in the activity of lysyl oxidase probably play a significant role in the establishment of flexion contracture of the fingers in Dupuytren's contracture.
Wound Complications in the Surgical Management of Dupuytren's Contracture: A Comparison of Operative Incisions
Authors: Gelberman R. H. , Panagis J. S. , Hergenroeder Patrick T. , Zakaib G. S.
Published: March 2006

A prospective study was carried out comparing the z-plasty, volar zig-zag and open-palm incisions in eighty-two patients undergoing partial selective fasciectomy for Dupuytren's disease. Flap necrosis, haematoma, and postoperative pain were greatest following the z-plasty and zig-zag incisions. While healing was somewhat delayed and a digital nerve was lacerated in the transverse open-palm group, the complication rate was lower overall and we now prefer this technique for partial selective fasciectomy for Dupuytren's disease.
Digital Nerve Grafts in Replanted Digits
Authors: Yamano Y. , Namba Y. , Hino Y. , Hasegawa T. , Ugawa A. , Ise M.
Published: March 2006

In most cases where digits have been amputated by avulsion and the digital nerve extensively injured, primary nerve suture cannot be performed. For such a digit when replanted, secondary nerve grafting was done under the operating microscope using a lateral femoral cutaneous nerve. Two years after operation, two-point discrimination of these cases proved to be 10.5 mm on average. And in the case of the transplanted three strand cable graft, using a lateral femoral cutaneous nerve yielded the most favourable results,. The replacement was superior to the side receiving primary crushed nerve suture. Sensory nerve action potentials indicate that the regenerated nerve does not necessarily mature sufficiently. The recovery of sensitivity even to this degree however was sufficient for the replanted digits to be useful in all cases.
The Y-Shaped Hypogastric—Groin Flap
Authors: Smith P. J.
Published: March 2006

We present a technique of providing complete skin cover for total degloving injuries of the hand and distal third of the forearm. This involves the use of a Y-shaped hypogastric groin flap. The proximal portion of the Y is tubed allowing the distal portion of each flap to be applied to the dorsal and volar surfaces respectively. This technique allows complete skin cover of both surfaces and yet retains the advantages of the groin flap in that it still has a long pedicle allowing the hand to be put through a full range of motion, speeding rehabilitation.
Tendon Ruptures in the Hand with Particular Reference to Attrition Ruptures in the Carpal Tunnel
Authors: Hallett J. P. , Motta G. R.
Published: March 2006

The mechanisms of tendon rupture in the hand are reviewed. Attrition ruptures of tendons in the carpal tunnel, other than those due to rheumatoid arthritis, are rare. A case is reported where Kienböck's avascular necrosis of the lunate caused rupture of flexor policis longus. This is the second case reported in the literature and serves as a model of attrition rupture.
Compression Arthrodesis of the Carpometacarpal Joint of the Thumb
Authors: Pardini Arlindo G. , Lazaroni Angelo P. , Tavares Kleber E.
Published: March 2006

Six cases of compression arthrodesis of the thumb carpometacarpal joint by the tension band technique are presented. All the cases healed in eight weeks or less. Complications as stiffness of other joints or osteoporosis are avoided by this method.
The Niebauer-Cutter Prosthesis in Excision Arthroplasty of the Trapezium
Authors: Rajan S. , Nylander G. , Fransson S. G.
Published: March 2006

Sixteen patients had excision arthroplasty of the trapezium, using the Niebauer-Cutter prosthesis. The average period of postoperative follow-up was thirteen months. All patients had severe preoperative disabilities and the majority were relieved from resting pain and pain during active use of their hands. The postoperative range of motion with regard to the palmar and radial abduction was found to be satisfactory, while varying degrees of limitation of circumduction was the rule. There was no correlation between the patients’ own judgment of the postoperative benefits and the objectively measured range of motion.

One patient had a luxation of the prosthesis, while another had a subluxation when opposing the thumb. This frequency of luxation/subluxation seems to be less than that experienced with the other common type of prosthesis, the Swanson prosthesis.

Although it is obvious that the ideal prosthesis for treatment of disabilities in the carpometacarpal joint of the thumb is still not available, it was concluded that the Niebauer-Cutter prosthesis is the best choice at the present.
Congenital Clawing of the Little Finger
Authors: Kimmel R. B. , Lamb D. W.
Published: March 2006

Three cases, with four fingers involved, of hyperextension at the metacarpophalangeal joint of the little finger, corrected by capsuloplasty of the volar plate.
Malignant Lymphoma with Intranodal Silicone Rubber Particles Following Metacarpophalangeal Joint Replacements
Authors: Digby Judith M.
Published: March 2006

A case of malignant lymphoma developing in a regional lymph node nine years after insertion of silastic finger prostheses is reported. A striking feature of the histology was the presence of multinucleated giant cells containing silastic particles, situated between the tumour cells. The significance of this is discussed.
The Fate of Injected Trigger Fingers
Authors: Kamhin M. , Engel J. , Heim M.
Published: March 2006

Patients who were scheduled for surgical release of their trigger fingers underwent an injection of the involved tendon sheath prior to surgery. In thirty-six patients the injection of methylene blue was undertaken in a proximal-distal direction and in forty-three the direction of the injection was reversed. The success rate of the injections was 61 per cent, in the proximal distal group and 37 per cent in the second group. There was no significant statistical difference with regard to age, but duration of the disorder and mode of injection regarding the different fingers did have statistical significance.
Structure of Capsules around Silicone Implants in Hand Surgery
Authors: Smahel J. , Meyer V.
Published: March 2006

Histological examination was made of twenty-three capsules around silicone implants used in hand surgery. The structure of the capsules was found to be similar to that seen in animal experiments, though they tended to be thicker. A further difference was the frequent occurrence of histiocytes accumulating near the inner margin of the capsule; these would quite frequently form a pseudoepithelium. Possible reasons for these differences are discussed. Silicone particles were found in the walls of two capsules around joint implants and their origin from the surface of the prosthesis demonstrated.
Rupture of Flexor Tendon Associated with Previous Fracture of the Hook of the Hamate.
Authors: Takami H. , Takahashi S. , Ando M.
Published: March 2006

Pathological rupture of the flexor tendons in the carpal tunnel is uncommon. In the case reported here, an ununited fracture of the hamate was thought responsible for a rupture of the flexor profundus tendon of the little finger.
Dupuytren's Contracture in a Black Female Child
Authors: Rosenfeld Nachman , Mavor Eliezer , Wise Leslie
Published: March 2006

A case of a thirteen-year-old black female with Dupuytren's contracture is presented. This patient is one of the youngest black female patients with Dupuytren's contracture.
Coastal ocean CO2–carbonic acid–carbonate sediment system of the Anthropocene
Authors: Andersson Andreas J. , Mackenzie Fred T. , Lerman Abraham
Published: March 2006

There is little doubt that human activities such as burning of fossil fuels and land use practices have changed and will continue to change the cycling of carbon in the global coastal ocean. In the present study, two biogeochemical box models were used to investigate the consequences of increasing atmospheric CO2 and subsequent ocean acidification and increasing riverine transport of organic matter and nutrients arising from human activities on land on the global coastal ocean between the years 1700 and 2300. Numerical simulations show that the net flux of CO2 between coastal ocean surface water and the atmosphere is likely to change during this time from net evasion to net invasion owing to increasing atmospheric CO2, increasing net ecosystem production arising from increasing nutrient loading to this region, and decreasing net ecosystem calcification due to lower carbonate ion concentration and subsequent lower surface water saturation state with respect to carbonate minerals. Model calculations show that surface water saturation state with respect to calcite will decrease 73% by the year 2300 under a business‐as‐usual scenario, which in concert with increasing temperature will cause overall biogenic calcification rate to decrease by 90%. Dissolution of carbonate minerals increased by 267% throughout the model simulation. This increase was in part due to increased invasion of atmospheric CO2, but mainly due to greater deposition and remineralization of land‐derived and in situ produced organic matter in the sediments, producing CO2 that caused pore water pH and carbonate saturation state to decrease. This decrease, in turn, drove selective dissolution of metastable carbonate minerals. As a consequence, the relative carbonate composition of the sediments changed in favor of carbonate phases with lower solubility than that of an average 15 mol% magnesian calcite phase. Model projected changes in surface water carbonate saturation state agree well with observations from the Hawaiian Ocean Time series and the calculated air‐sea CO2 exchange agrees well with a recent independent estimate of this flux derived from measurements from diverse coastal ecosystems scaled up to the global coastal ocean area.
Riverine nitrogen export from the continents to the coasts
Authors: Boyer Elizabeth W. , Howarth Robert W. , Galloway James N. , Dentener Frank J. , Green Pamela A. , Vörösmarty Charles J.
Published: March 2006

We present an overview of riverine nitrogen flux calculations that were prepared for the International Nitrogen Initiative's current global assessment of nitrogen cycles: past, present, and future (Galloway et al., 2004). We quantified anthropogenic and natural inputs of reactive nitrogen (N) to terrestrial landscapes and the associated riverine N fluxes. Anthropogenic inputs include fossil‐fuel derived atmospheric deposition, fixation in cultivated croplands, fertilizer use, and the net import in human food and animal feedstuffs. Natural inputs include natural biological N fixation in forests and other noncultivated vegetated lands, and fixation by lightning. We use an empirical model relating total N inputs per landscape area to the total flux of N discharged in rivers based on watershed data from contrasting ecosystems spanning multiple spatial scales. With this approach, we simulate riverine N loads to the coastal zone and to inland waters from the continents. Globally, rivers exported about 59 Tg N yr−1, with 11 Tg N yr−1 transported to dry lands and inland receiving waters, and 48 Tg N yr−1 transported to the coastal zone. Rates of riverine N loss vary greatly among the continents, reflecting the regional differences in population and the associated anthropogenic N inputs. We compare our estimates to other approaches that have been reported in the literature. Our work provides an understanding of the sources of N to landscapes and the associated N fluxes in rivers, and highlights how anthropogenic activities impact N cycling around the world.
Role of eddies in cooling the Leeuwin Current
Authors: Domingues Catia M. , Wijffels Susan E. , Maltrud Mathew E. , Church John A. , Tomczak Matthias
Published: March 2006

The poleward flow of the Leeuwin Current dominates the surface circulation off Western Australia. Along its path, it cools by about 5°C over 1350 km. Based on an eddy permitting simulation using the Parallel Ocean Program model, we find that 70% of the heat advected into the coastal region off Western Australia by the narrow mean jet is transferred to the ocean interior through eddy heat fluxes. The eddy fluxes are associated with processes operating at submonthly timescales and despite the current's clear seasonal variability, seasonal rectification plays little role in the mean heat balance. The 43 TW transferred offshore by eddies is the primary means by which the ocean interior (22°S–34°S and east of 107°E) is warmed and the Leeuwin Current cooled. The Leeuwin Current jet and the eddies allow air–sea fluxes to transfer over 40 W m−2 of heat to the atmosphere in the southeast Indian Ocean.
Lithospheric structure beneath trans‐Carpathian transect from Precambrian platform to Pannonian basin: CELEBRATION 2000 seismic profile CEL05
Authors: Grad Marek , Guterch Aleksander , Keller G. Randy , Janik Tomasz , Hegedűs Endre , Vozár Jozef , Ślączka Andrzej , Tiira Timo , Yliniemi Jukka
Published: March 2006

In 2000, a consortium of European and North American institutions completed a huge active source seismic experiment focused on central Europe, the Central European Lithospheric Experiment Based on Refraction or CELEBRATION 2000. This experiment primarily consisted of a network of seismic refraction profiles that extended from the East European craton, along and across the Trans‐European suture zone region in Poland to the Bohemian massif, and through the Carpathians and eastern Alps to the Pannonian basin. The longest profile CEL05 (1420 km) is the focus of this paper. The resulting two‐dimensional tomographic and ray‐tracing models show strong variations in crustal and lower lithospheric structure. Clear crustal thickening from the Pannonian basin (24–25 km thick) to the Trans‐European suture zone region (∼50 km), together with the configuration of the lower lithospheric reflectors, suggests northward subduction of mantle underlying Carpathian‐Pannonian plate under the European plate. This, however, conflicts with strong geological evidence for southward subduction, and we present three tectonic models that are to not totally mutually exclusive, to explain the lithospheric structure of the area: (1) northward “old” subduction of the Pannonian lithosphere under the East European craton in the Jurassic–Lower Cretaceous, (2) a collisional zone containing a “crocodile” structure where Carpatho‐Pannonian upper crust is obducting over the crystalline crust of the East European craton and the Carpathian‐Pannonian mantle lithosphere is underthrusting cratonic lower crust, and (3) lithosphere thinning due to the effects of Neogene extension and heating with the slab associated with “young” subduction southward in the Miocene having been either detached and/or rolled back to the east. In the last case, the northwestward dipping in the lithosphere can be interpreted as being due to isotherms that could represent the lithosphere/asthenosphere boundary in the Pannonian region.
Mapping mantle flow during retreating subduction: Laboratory models analyzed by feature tracking
Authors: Funiciello F. , Moroni M. , Piromallo C. , Faccenna C. , Cenedese A. , Bui H. A.
Published: March 2006

Three‐dimensional dynamically consistent laboratory models are carried out to model the large‐scale mantle circulation induced by subduction of a laterally migrating slab. A laboratory analogue of a slab–upper mantle system is set up with two linearly viscous layers of silicone putty and glucose syrup in a tank. The circulation pattern is continuously monitored and quantitatively estimated using a feature tracking image analysis technique. The effects of plate width and mantle viscosity/density on mantle circulation are systematically considered. The experiments show that rollback subduction generates a complex three‐dimensional time‐dependent mantle circulation pattern characterized by the presence of two distinct components: the poloidal and the toroidal circulation. The poloidal component is the answer to the viscous coupling between the slab motion and the mantle, while the toroidal one is produced by lateral slab migration. Spatial and temporal features of mantle circulation are carefully analyzed. These models show that (1) poloidal and toroidal mantle circulation are both active since the beginning of the subduction process, (2) mantle circulation is intermittent, (3) plate width affects the velocity and the dimension of subduction induced mantle circulation area, and (4) mantle flow in subduction zones cannot be correctly described by models assuming a two‐dimensional steady state process. We show that the intermittent toroidal component of mantle circulation, missed in those models, plays a crucial role in modifying the geometry and the efficiency of the poloidal component.
Vertical mixing effects on the phytoplankton bloom in the southeastern Bering Sea midshelf
Authors: Jin Meibing , Deal Clara J. , Wang Jia , Tanaka Nori , Ikeda Moto
Published: March 2006

A vertically one‐dimensional ecosystem model was developed and applied to the southeastern Bering Sea middle shelf. The physical model includes a 2.5‐level turbulence model. Tidal forcing was introduced to improve representation of tidal mixing in addition to wind stirring and thermal stratification. The simulated currents, thermocline and mixed‐layer depth (MLD) agree well with observations. The biological model was adapted from Eslinger et al. (2001) with nine compartments. The onset, magnitude and duration of the spring phytoplankton blooms were realistically reproduced at 12 m, 24 m, and 44 m in the standard run. The spring phytoplankton bloom was dominated by diatoms, and the post blooms by flagellates, which agree with previous studies in the region. The peak phytoplankton biomass reached 8 mmol N m−3, or approximately 16 mg Chl m−3, comparable to that observed in the PROBES program in 1980 and 1981 (Eslinger and Iverson, 2001). The simulated primary productions were within the range of 60 to 200 g C m−2/yr estimated in previous studies. Sensitivity studies revealed distinct effects of tidal mixing, wind stirring, thermal stratification and their impacts on the timing and magnitude of the phytoplankton bloom and the gross and net primary production. Links of MLD with primary production and species were found. If a constant MLD is used in the model, there exists a maximum gross primary production (GPP) at MLD = 24 m. Model results reveals that the predominant phytoplankton species changes from flagellates when MLD < 15 m to diatoms when MLD > 15 m.
Currents in the Aleutian Basin and subarctic North Pacific near the dateline in summer 1993
Authors: Chen Shuiming , Firing Eric
Published: March 2006

The currents in the Aleutian Basin of the Bering Sea and in the subarctic North Pacific near the dateline in summer 1993 are described, based on Shipboard Acoustic Doppler Current Profiler and Lowered Acoustic Doppler Current Profiler velocity measurements and on conductivity‐temperature‐depth profiles. The strongest flow is the Alaskan Stream with velocities up to 90 cm s−1 and with a subsurface core as narrow as 30 km at about 150 m depth. Velocity at the bottom below the Alaskan Stream could not be distinguished from zero. The inflow of the Alaskan Stream through Amchitka Pass accounted for about 70% of the Aleutian North Slope Current in the Aleutian Basin. Two anticyclonic eddies occupied most of the Aleutian Basin along the cruise track. Both eddies extended to the bottom.
Sea‐salt aerosol response to climate change: Last Glacial Maximum, preindustrial, and doubled carbon dioxide climates
Authors: Mahowald Natalie M. , Lamarque Jean‐François , Tie Xue Xi , Wolff Eric
Published: March 2006

Sea‐salt aerosols represent a significant fraction of the aerosol optical depth over the oceans, and thus their response to changes in climate represents an important potential feedback on climate. Model results for sea‐salt aerosols in the Community Atmospheric Model (CAM3) show good agreement with observations for the current climate. Additionally, the current climate model simulations presented here are not sensitive to the sea surface temperature boundary conditions or model resolution. We show model results for the response of sea‐salt aerosols to climate change for the Last Glacial Maximum, preindustrial, current, and doubled carbon dioxide climate model simulations. Our model results suggest that globally averaged sea‐salt sources, deposition, and loading are not very sensitive to climate change and change <5% for these disparate climates. Regional differences are much larger, with differences in zonally averaged concentrations as large as 40% seen between the current climate and a doubled carbon dioxide climate. While ice core studies show twofold to fivefold changes in sea‐salt fluxes between Last Glacial Maximum and the current climate, our simulations cannot reproduce these changes, even after including a proposed sea ice source of sea salts.
Effect of carbon isotopic variations on measured CO2 abundances in reference gas mixtures
Authors: Lee Jee‐Yon , Yoo Hee‐Soo , Marti Kurt , Moon Dong Min , Lee Jin Bok , Kim Jin Seog
Published: March 2006

Changes in the Earth's climate caused by global warming are a looming problem that poses serious challenges not only for our generation but for future generations. An accurate determination of CO2 gas plays a critical role in this field of research. The measurement of greenhouse gases is pivotal to understanding the changes in Earth's climate and needs to be carried out with a high degree of accuracy. Precision measurements on a 0.1 μmol/mol scale may provide research data for precisely monitoring the continuing changes that the planet is undergoing. The World Meteorological Organization (WMO) has recommended that carbon dioxide concentrations in air can be measured by comparing these with national reference gases using a nondispersive infrared (NDIR) analyzer to standardize international data. The CO2 molecules absorb the distinctive resonant frequencies in IR spectrometers. The NDIR analyzers usually use narrow band path filter to determine 12CO2 in all carbon dioxide molecules, which can possibly ignore the measurement of 13CO2 partially or totally. However, if the carbon isotopic abundances of CO2 samples deviate from those in standard CO2 gas, the NDIR measurement will not be exact. For accurate measurements, producers of reference gas mixtures either must use gas with natural isotopic abundances, or report the isotopic abundances of CO2. In order to document shifts based on isotopic variability, we prepared artificial air as CO2 reference gas mixtures gravimetrically with CO2 having different carbon isotopic signatures to study the resulting isotopic variations. We used different δ13C values of two CO2 source gases, A and B, corresponding to −41.97‰ and −14.88‰, respectively, which were measured using an isotope ratio mass spectrometer. One set of reference gas mixtures (A1 to A5) was prepared from the CO2 source of δ13C = −41.97‰, and the other set of reference gas mixtures (B1, B2) was prepared from that of δ13C = −14.88‰. The CO2 abundances of the two sets of mixtures were compared by using NDIR. The reproducibility test for the set A showed that the data are consistent within uncertainty (calibration line was obtained by the best secondary polynomial least squares fit). The uncertainty of CO2 concentration in the reference gas mixtures are 0.06 μmol/mol with a 95% confidence level. The reproducibility of the NDIR measurement is 0.012 μmol/mol (standard deviation). The difference between the set A (A1 to A5) and set B (B1, B2) was found to be 0.17 ± 0.01 μmol/mol, which is in excellent agreement with the theoretically predicted value of 0.17 μmol/mol.
Measurements of nitrogen dioxide total column amounts using a Brewer double spectrophotometer in direct Sun mode
Authors: Cede Alexander , Herman Jay , Richter Andreas , Krotkov Nickolay , Burrows John
Published: March 2006

NO2 column amounts were measured for the past 2 years at Goddard Space Flight Center, Greenbelt, Maryland, using a Brewer spectrometer in direct Sun mode. A new “bootstrap” method to calibrate the instrument is introduced and described. This technique selects the cleanest days from the database to obtain the solar reference spectrum. The main advantage for direct Sun measurements is that the conversion uncertainty from slant column to vertical column is negligible compared to the standard scattered light observations where it is typically on the order of 100% (2σ) at polluted sites. The total 2σ errors of the direct Sun retrieved column amounts decrease with solar zenith angle and are estimated at 0.2 to 0.6 Dobson units (DU, 1 DU ≈ 2.7 × 1016 molecules cm−2), which is more accurate than scattered light measurements for high NO2 amounts. Measured NO2 column amounts, ranging from 0 to 3 DU with a mean of 0.7 DU, show a pronounced daily course and a strong variability from day to day. The NO2 concentration typically increases from sunrise to noon. In the afternoon it decreases in summer and stays constant in winter. As expected from the anthropogenic nature of its source, NO2 amounts on weekends are significantly reduced. The measurements were compared to satellite retrievals from Scanning Image Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY). Satellite data give the same average NO2 column and show a seasonal cycle that is similar to the ground data in the afternoon. We show that NO2 must be considered when retrieving aerosol absorption properties, especially for situations with low aerosol optical depth.
Prevention of Apoptosis-Inducing Factor Translocation is a Possible Mechanism for Protective Effects of Hepatocyte Growth Factor against Neuronal Cell Death in the Hippocampus after Transient Forebrain Ischemia
Authors: Niimura Makiko , Takagi Norio , Takagi Keiko , Mizutani Reiko , Ishihara Naoko , Matsumoto Kunio , Funakoshi Hiroshi , Nakamura Toshikazu , Takeo Satoshi
Published: March 2006

Hepatocyte growth factor (HGF) is one of the prospective agents for therapy against a variety of neurologic and neurodegenerative disorders, although the precise mechanisms for the effect of HGF remain to be elucidated. We showed that treatment with HGF protected hippocampal cornu ammonis (CA) subregion 1 neurons from apoptotic cell death after transient forebrain ischemia. Accumulating evidence indicates that ischemia-induced neuronal damage occurs via caspase-independent pathways. In the present study, we focused on the localization of apoptosis-inducing factor (AIF), which is an important protein in the signal-transduction system through caspase-independent pathways, to investigate the possible mechanism for the protective effect of HGF after transient forebrain ischemia. Hepatocyte growth factor attenuated the increase in the expression of AIF protein in the nucleus after transient forebrain ischemia. We further explored the upstream components of AIF translocation. Primary DNA damage induced by Ca2+ influx and subsequent NO formation are thought to be the initial events for AIF translocation, which results in the subsequent DNA damage by AIF. Hepatocyte growth factor prevented the primary oxidative DNA damage, as was estimated by using anti-8-OHdG (8-hydroxy-2'-deoxyguanosine) antibody. Oxidative DNA damage after ischemia is known to lead to the activation of poly(ADP-ribose) polymerase (PARP) and p53, resulting in AIF translocation. Marked increases in the PAR polymer formation and the expression of p53 protein after ischemia were effectively prevented by HGF treatment. In the present study, we first showed that HGF was capable of preventing neuronal cell death by inhibiting the primary oxidative DNA damage and then preventing the activation of the PARP/p53/AIF pathway.
Ischemic Cerebral Tissue Response to Subventricular Zone Cell Transplantation Measured by Iterative Self-Organizing Data Analysis Technique Algorithm
Authors: Li Lian , Jiang Quan , Zhang Li , Ding Guangliang , Wang Lei , Zhang Ruilan , Zhang Zheng G , Li Qingjiang , Ewing James R , Kapke Alissa , Lu Mei , Chopp Michael
Published: March 2006

To investigate the changes of the ischemic lesion in rat brain after subventricular zone (SVZ) cell transplantation and the influence of the grafted cells on the appearance of angiogenesis, Svz cells, superparamagnetically labeled, were intracisternally transplanted into the rat brain 48 h after onset of embolic stroke. A complete set of magnetic resonance (MR) images was acquired for all animals with ( n = 8) and without ( n = 3) cell grafting at approximately 24 h, 72 h, and weekly for 6 weeks after stroke. Transplanted cells were tracked by high-resolution three-dimensional gradient-echo images and the interaction between the cells and ischemic lesion was detected by ISODATA (Iterative Self-Organizing Data Analysis Technique Algorithm) calculated from T1, T2 and T1sat maps. Tissue status from ISODATA was characterized by a specific signature, which represents the deviation from normal tissue in the feature space. Transplanted SVZ cells selectively migrated towards the ischemic side of the rat brain and approached the lesion boundary within 1-week after grafting. Cell treated rats exhibited a significant reduction of average lesion size compared with control rats ( P < 0.05). A significant reduction of tissue signature ( P < 0.001) induced by cell transplantation was localized to the position of grafted cells, and these sites exhibited stably restored cerebral blood flow (CBF) (approximately 85% of normal CBF). Angiogenesis was present in sites either immediately adjacent to or surrounded by the grafted cells. Our data indicate that map-ISODATA accurately and dynamically characterizes the ischemic lesion and its response to cell therapy.
Size-dependent interface energy
Authors: Ouyang G. , Liang L. H. , Wang C. X. , Yang G. W.
Published: March 2006

A universal and analytic thermodynamic model without any adjustable parameters was established to elucidate the interface energy of multilayers at the nanometer scale by taken the size effect, the interfacial orientation, and the interfacial mismatch into account. Theoretical predictions were consistent with the calculations of the modified analytical embedded atom method and the experimental data, implying that the proposed thermodynamic model could be expected to be a general approach on nanoscale to understand interface energy in binary systems.
Elastic properties of swollen polyelectrolyte gels in aqueous salt solutions
Authors: Sasaki Shigeo
Published: March 2006

The elastic relaxation responding to a uniaxially stretched poly(acrylic acid) rodlike gel in the aqueous NaCl solution was investigated. The relaxation elucidated the shear (μ) and bulk (K) moduli and the frictional coefficients (ς) of the fully ionized gel at pH above 9 as functions of the degree of swelling, which was controlled by the NaCl concentration (CS) of the solution. Two gels, cross-linked chains of which consist of 500 (GelA500) and 50 (GelA50) monomeric units, were examined to investigate the effect of the chain length on the elastic behavior. The moduli of GelA500 increased with swelling at CS below 100 mM and decreased at CS above it. The μ values of both gels can be characterized by the power function of gel diameter, d as μ∝dβ. The β values being −1 at CS above 100 mM transitionally changed to 1.2 at CS about 100 mM. That is, the dimensionality of space for the chains to distribute, ndim {=(β+5)∕(β+2) according to the conventional theory [Sasaki et al., J. Chem. Phys. 102, 5694 (1995)]}, changed from 4 (ndim of ideal chain) to 1.9 at CS=100mM. This indicates that the electrostatic repulsion between gel chains reduces the ndim at CS below 100 mM but not at CS above it. It was found that the K values of GelA500 were well described by the conventional theory but those of GelA50 not. The ςzr∕ςrr (ςzr is an off-diagonal element of the friction coefficient tensor and ςrr is a diagonal element of the friction coefficient tensor) was found to be 2.7×10−2, which was the same as the previously reported value for the swollen poly(acrylamide) gel [Sasaki, J. Chem. Phys. 120, 5789 (2004)]. The ςrr of unit volume of the GelA500 is well explained by the free draining model while the ςrr of GelA50 is less than that of the free draining model, suggesting the slip between water and ionized chain.
Reaction dynamics of CN+O2→NCO+O(P23)
Authors: Witinski Mark F. , Ortiz-Suárez Marívi , Davis H. Floyd
Published: March 2006

We have used oxygen Rydberg time-of-flight spectroscopy to carry out a crossed molecular beam study of the CN+O2 reaction at collision energies of 3.1 and 4.1kcal∕mol. The O(P23) products were tagged by excitation to high-n Rydberg levels and subsequently field ionized at a detector. The translational energy distributions were broad, indicating that the NCO is formed with a wide range of internal excitation, and the angular distribution was forward-backward symmetric, indicating the participation of NCOO intermediates with lifetimes comparable to or longer than their rotational periods. Rice-Ramsperger-Kassel-Marcus modeling of the dissociation of NCOO to NCO+O suggests that Do(NC–OO)⩾38kcal∕mol, which is consistent with several theoretical calculations. Implications for the competing CO+NO channel are discussed.
Atomistic simulation of helium-defect interaction in alpha-iron
Authors: Yang L. , Zu X. T. , Xiao H. Y. , Gao F. , Heinisch H. L. , Kurtz R. J. , Liu K. Z.
Published: March 2006

Molecular dynamics (MD) methods are utilized to study the formation of vacancy clusters created by displacement cascades in α-Fe containing different concentrations of substitutional He atoms. Primary knock-on atom energies, Ep, from 500eV to 20keV are considered at a temperature of 100K, and the results are compared with those performed in pure α-Fe. There are distinct differences in the number and size of vacancy clusters within displacement cascades with and without substitutional helium atoms. It is found that many large vacancy clusters can be formed within cascade cores in α-Fe with helium atoms, in contrast to a few small vacancy clusters observed in pure α-Fe. The number and size of helium/vacancy clusters generally increase with increasing helium concentration and PKA energy. One of the striking results is that the number of self-interstitial atoms (SIAs) and the size of interstitial clusters are much smaller than those in pure α-Fe.
Microfabrication of millimeter wave vacuum electron devices by two-step deep-etch x-ray lithography
Authors: Shin Young-Min , So Jin-Kyu , Han Seong-Tae , Jang Kyu-Ha , Park Gun-Sik , Kim Jong-Hyun , Chang Suk-Sang
Published: March 2006

The circuits for millimeter wave vacuum electron devices with all circuit elements including an electron beam tunnel are microfabricated by two-step deep-etch x-ray lithography (x-ray LIGA). The discrepancies of eigenfrequency between experiment and simulation are within 1.1% in a coupled-cavity structure and 1.4% in a folded waveguide structure when the operating frequency is about 100GHz. Furthermore, a measured tolerance of below 2μm, and a measured surface roughness of 20–70nm, of LIGA-fabricated circuits implies the two-step LIGA microfabrication has potential applications up to the submillimeter wave region.