bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical Implications of Household Food Security: Definitions, Monitoring, and Policy
Authors: Cook John T. 
Published: March 2003

AbstractPoverty‐related food insecurity is a reality that many clinicians in nutrition and health care encounter either directly or indirectly. It is associated with both overnutrition and undernutrition, but it is not congruent with malnutrition. Food insecurity affects human development and health throughout the lifecycle, but can be particularly harmful during critical or vulnerable stages early and late in life. Understanding the causes and consequences of food insecurity and knowing how to identify them can improve the quality and effectiveness of clinical care, and facilitate prevention and treatment of many kinds of health problems. Numerous public policies and programs exist to ameliorate and prevent poverty‐related food insecurity. However, the resources to support them ebb and flow with the politics of annual state and federal budgetary cycles. Support and need for these social‐safety‐net programs also vary with business cycles. Unfortunately, need often expands as support shrinks along with employment and government revenues during recessions, and shrinks as support expands along with employment and government revenues during expansions.
Pharmacologic B‐Vitamin Therapy for Hyperhomocysteinemia in Dialysis Patients: Has the Time Come?
Authors: Friedman Allon N. 
Published: March 2003

AbstractHyperhomocysteinemia, the state of elevated plasma homocysteine levels, is an independent risk factor for atherothrombosis and arteriosclerosis. For incompletely understood reasons, renal disease appears to predispose to hyperhomocysteinemia. In fact, as renal function declines, plasma homocysteine levels rise. Mild to moderate hyperhomocysteinemia is almost universal among end‐stage renal disease (ESRD) patients, who have negligible functioning renal mass. This tendency towards a hyperhomocysteinemic state may partially explain the dramatically high rate of cardiovascular morbidity and death seen in this population. Hyperhomocysteinemic subjects with normal kidney function can usually reduce or normalize homocysteine levels with modest B‐vitamin (folic acid, vitamin B6, vitamin B12) supplementation. However, subjects with reduced renal function require much higher (“pharmacologic”) B‐vitamin doses to achieve equivalent reductions, while ESRD subjects are resistant to even massive doses. Study design flaws and the inclusion of potentially B‐vitamin‐deficient subjects in homocysteine‐lowering trials has made interpretation of this literature difficult. Nonetheless, it appears that the modest standard daily dialysis vitamin supplements are equivalent to pharmacologic B‐vitamin therapy in lowering homocysteine levels in ESRD patients and should be the recommended method of treatment in this population at the present time.
Inverted metamorphism and the Main Central Thrust: field relations and thermobarometric constraints from the Kishtwar Window, NW Indian Himalaya
Authors: Stephenson  , Waters  , Searle  
Published: March 2003

Following the early Eocene collision of the Indian and Asian plates, intracontinental subduction occurred along the Main Central Thrust (MCT) zone in the High Himalaya. In the Kishtwar–Zanskar Himalaya, the MCT is a 2 km thick shear zone of high strain, distributed ductile deformation which emplaces the amphibolite facies High Himalayan Crystalline (HHC) unit south‐westwards over the lower greenschist facies Lesser Himalaya. An inverted metamorphic field gradient, mapped from the first appearance of garnet, staurolite and kyanite index minerals, is coincident with the high strain zone. Petrography and garnet zoning profiles indicate that rocks in the lower MCT zone preserve a prograde assemblage, whereas rocks in the HHC unit show retrograde equilibration. Thermobarometric results derived using THERMOCALC indicate a P–T  increase of c. 180 °C and c. 400 MPa across the base of the MCT zone, which is a consequence of the syn‐ to postmetamorphic juxtaposition of M1 kyanite grade rocks of the HHC unit on a cooling path over biotite grade footwall rocks, which subsequently attain their peak (M2) during thrusting. Inclusion thermobarometry from the lower MCT zone reveals that M2 was accompanied by loading, and peak conditions of 537±38 °C and 860±120 MPa were attained. M1 kyanite assemblages in the HHC unit, which have not been overprinted by M2 fibrolitic sillimanite, were not significantly affected by M2, and conditions of equilibration are estimated as 742±53 °C and 960±180 MPa.There is no evidence for dissipative or downward conductive heating in the MCT zone. Instead, the primary control on the distribution of peak assemblages, represented by the index minerals, is postmetamorphic ductile thrusting in a downward propagating shear zone. Polymetamorphism and diachroneity of equilibration are also important controls on the thermal profile through the MCT zone and HHC unit.
The P–T record of synchronous magmatism, metamorphism and deformation at Petrel Cove, southern Adelaide Fold Belt
Authors: Alias G. , Sandiford M. , Hand M. , Worley B. 
Published: March 2003

AbstractPorphyroblastic schists in the thermal aureole of the Victor Harbor Granite at Petrel Cove, in the southern Adelaide Fold Belt, South Australia, preserve a record of sequential cordierite, andalusite, staurolite, fibrolite, chlorite and muscovite growth (along with biotite+plagioclase+quartz+ilmenite) during progressive deformation. A P–T pseudo‐section appropriate to biotite‐saturated assemblages in KFMASH shows that the sequence of mineral reactions records increasing pressure of at least 1 kbar (from c. 3 to c. 4 kbar) during cooling from around 580 °C. Heating at pressures below c. 3 kbar is inferred for growth of early formed cordierite porphyroblasts, and is attributed in part to the thermal effects of granite emplacement, while the pressure increase is attributed to tectonic burial accruing from ongoing deformation. The ‘anticlockwise’P–T path is consistent with convergent deformation being focussed as a consequence of heating, as to be expected for a lithospheric rheology that is strongly temperature dependent.
Near‐isothermal decompression within a clockwise P–T evolution recorded in migmatitic mafic granulites from Clavering Ø, NE Greenland: implications for the evolution of the Caledonides
Authors: Jones K. A. , Escher J. C. 
Published: March 2003

AbstractThe high grade rocks (metapelites and metabasites) of Clavering Ø represent the easternmost exposures of granulites in the Palaeozoic Caledonian Orogen of East Greenland. Mafic granulites which occur as sheet‐like bodies and lenses within metapelitic migmatites and orthogneiss complexes have experienced migmatisation and mineral equilibria which define a clockwise P–T path incorporating a near‐isothermal decompression segment. Textures demonstrate the existence of early garnet‐clinopyroxene‐melt assemblages which equilibrated at >8–11 kbar and 850–915 °C. Subsequently, decompression melting led to formation of orthopyroxene‐plagioclase‐melt assemblages at conditions below >8–11 kbar. Continued syn‐deformational decompression is indicated by a combination of both static and syn‐deformational recrystallization textures which generated finer grained orthopyroxene‐plagioclase assemblages. P–T constraints indicate these assemblages equilibrated at c. 5.0–6.5 kbar at 850–915 °C. These data are consistent with the rocks undergoing a stage of rapid tectonic‐induced exhumation involving some 3.0–4.5 kbar (c.10–12 km) uplift as part of a clockwise P–T path in a collisional setting.
Melt‐producing and melt‐consuming reactions in the Achankovil cordierite gneisses, South India
Authors: Cenki B. , Kriegsman L. M. , Braun I. 
Published: March 2003

AbstractMigmatitic cordierite gneisses within the Achankovil Zone (AZ) of southern Pan‐African India record melt‐producing and subsequent melt‐consuming mineral reactions. Early mineral assemblages Bt‐Sil‐Qtz and Bt‐Sil‐Spl, deduced from inclusion textures in garnet prophyroblasts, break down via successive dehydration melting reactions to high‐Tphase assemblages (e.g. Grt‐Crd‐Liq, Opx‐Liq, Spl‐Crd‐Liq). Later back reactions between the restite and thein situcrystallizing melt resulted in thin cordierite coronas separating garnet from the leucosome, and partial resorption of garnet to Opx‐Crd or Crd‐Bt‐Qtz symplectites. Leucosomes generally display a moderate (low‐strain gneisses) to strong (high‐strain gneisses) depletion of alkali feldspar attributed to mineral‐melt back reactions partly controlled by the degree of melt segregation.Using a KFMASH partial petrogenetic grid that includes a melt phase, and qualitative pseudosections for microdomains of high and low Al/Si ratios, the successive phase assemblages and reaction textures are interpreted in terms of a clockwiseP–Tpath culminating at about 6–7 kbar and 900–950 °C. ThisP–Tpath is consistent with, but more detailed than published results, which suggests that taking a melt phase into account is not only a valid, but also a useful approach. ComparingP–Tdata and lithological and isotopic data for the AZ with adjacent East Gondwana fragments, suggests the presence of a coherent metasedimentary unit exposed from southern Madagascar via South India (AZ) and Sri Lanka (Wanni Complex) to the Lützow–Holm Bay in Eastern Antarctica.
Raman spectra of carbonaceous material in metasediments: a new geothermometer
Authors: Beyssac O. , Goffé B. , Chopin C. , Rouzaud J. N. 
Published: March 2003

AbstractMetasedimentary rocks generally contain carbonaceous material (CM) deriving from the evolution of organic matter originally present in the host sedimentary rock. During metamorphic processes, this organic matter is progressively transformed into graphite s.s. and the degree of organisation of CM is known as a reliable indicator of metamorphic grade. In this study, the degree of organisation of CM was systematically characterised by Raman microspectroscopy across several Mesozoic and Cenozoic reference metamorphic belts. This degree of organisation, including within‐sample heterogeneity, was quantified by the relative area of the defect band (R2 ratio). The results from the Schistes Lustrés (Western Alps) and Sanbagawa (Japan) cross‐sections show that (1) even through simple visual inspection, changes in the CM Raman spectrum appear sensitive to variations of metamorphic grade, (2) there is an excellent agreement between the R2 values calculated for the two sections when considering samples with an equivalent metamorphic grade, and (3) the evolution of the R2 ratio with metamorphic grade is controlled by temperature (T). Along the Tinos cross‐section (Greece), which is characterised by a strong gradient of greenschist facies overprint on eclogite facies rocks, the R2 ratio is nearly constant. Consequently, the degree of organisation of CM is not affected by the retrogression and records peak metamorphic conditions. More generally, analysis of 54 samples representative of high‐temperature, low‐pressure to high‐pressure, low‐temperature metamorphic gradients shows that there is a linear correlation between the R2 ratio and the peak temperature [T(°C) = −445 R2 + 641], whatever the metamorphic gradient and, probably, the organic precursor. The Raman spectrum of CM can therefore be used as a geothermometer of the maximum temperature conditions reached during regional metamorphism. Temperature can be estimated to ± 50 °C in the range 330–650 °C. A few technical indications are given for optimal application.
Metamorphic history of high‐pressure granulites in Payer Land, Greenland Caledonides
Authors: Elvevold S. , Thrane K. , Gilotti J. A. 
Published: March 2003

AbstractA high‐P granulite facies gneiss complex occurs in north‐west Payer Land (74°28′−74°47′N) in the central part of the East Greenland Caledonian (Ordovician–Devonian) orogen. High‐P metamorphism of the Payer Land gneiss complex resulted in formation of the assemblages Grt + Cpx + Amp + Qtz + Ru ± Pl in mafic rocks, and Grt + Ol + Cpx + Opx + Spl in rare ultramafic pods. Associated metapelites experienced anatexis in the kyanite stability field. Peak metamorphic assemblages formed around 800–850 °C at pressures of c. 1.4–1.7 GPa, corresponding to crustal depths of c. 50 km. Mafic granulites contain abundant reaction textures, including the replacement of garnet by symplectites of Opx + Spl + Pl, indicating that the high‐P event was followed by decompression while the granulites remained at elevated temperatures. Charnockitic gneisses from Payer Land show evidence of late Archean (c. 2.8–2.4 Ga) crustal growth and subsequent Palaeoproterozoic (c. 1.85 Ga) metamorphism. The gneiss complex experienced intense reworking during the Caledonian continental collision. On the basis of Caledonian monazite ages recorded from the high‐P anatectic metapelites, the clockwise P–T evolution and formation of the high‐P granulite facies assemblages is related to Caledonian crustal thickening, which resulted in formation of eclogites approximately 300 km north of Payer Land. The Payer Land granulites comprise a metamorphic core complex, which is separated from the overlying low‐grade supracrustal rocks (the Neoproterozoic Eleonore Bay Supergroup) by a late Caledonian extensional fault zone, the Payer Land Detachment. The steep, nearly isothermal, unloading P–T path recorded by the granulites can be explained by erosional and tectonic unroofing along the Payer Land Detachment.
Metamorphism of the deepest exposed arc rocks in the Cretaceous to Paleogene Cascades belt, Washington: evidence for large‐scale vertical motion in a continental arc
Authors: Valley P. M. , Whitney D. L. , Paterson S. R. , Miller R. B. , Alsleben H. 
Published: March 2003

AbstractThe Swakane Gneiss and the overlying Napeequa Complex in the North Cascade range, Washington, were metamorphosed and deformed during development of a Cretaceous‐Paleogene continental arc, and are among the structurally deepest exposed rocks within the Cordilleran arcs of North America. Peak metamorphic conditions in both the Swakane Gneiss and Napeequa Complex were c. 640–750 °C, 9–12 kbar. Clockwise paths and widespread evidence for high‐P metamorphism in meta‐supracrustal rocks (burial to >40 km) document major vertical tectonic motion during arc construction and unroofing.These and other moderately high‐pressure rocks in the North Cascades‐Coast Mountains experienced a dramatically different tectonometamorphic history than metamorphic rocks within other Cordilleran arcs. The exhumed arc complexes of the Sierra Nevada and Peninsular Ranges are dominated by relatively low‐P metamorphic and plutonic rocks (typically <6 kbar). There is no evidence that the northern Cordillera was thickened to a greater degree than these other belts, suggesting that the greater magnitude of vertical motion in the Cascades may have been related to exhumation mechanisms: Eocene extension in the northern Cordillera vs. erosional unroofing in the central and southern Cordillera.
ACID‐BASE IN RENAL FAILURE: Acid‐Base Balance in Dialysis Patients
Authors: Gennari F. John 
Published: March 2003

ABSTRACTAcid‐base balance in dialysis patients is achieved by a unique interaction between the patient and the particular mode of renal replacement therapy. The prevailing serum HCO3− in these patients is determined not only by endogenous acid production but also by the nature of the dialysis prescription and, in particular, by the bicarbonate (or lactate) concentration of the bath solution. Despite the technical advances in dialysis therapy, pre‐dialysis serum HCO3− remains lower than normal in most patients receiving hemodialysis and in many patients receiving peritoneal dialysis. A central question is whether even a mild degree of acidosis increases morbidity and mortality in patients with end‐stage renal disease. This article reviews the nature of the acid‐base equilibrium achieved in patients receiving hemodialysis or peritoneal dialysis, addresses the question of whether correction of acidosis is beneficial, and reviews the techniques for increasing serum HCO3− in these patients. Based on the information available, it is clear that the patient with a serum HCO3− less than 19 mEq/L should be assessed to determine the cause of the low value and steps undertaken to correct the acidosis. Whether patients with steady‐state values between 19 and 24 mEq/L require specific attention remains an issue for further investigation.
Hemodialyzer Membranes and Configurations: A Historical Perspective
Authors: Clark William R. 
Published: March 2003

ABSTRACTThe principle of hemodialysis (HD) was first described over a century ago while the first human HD treatment was performed in 1923 with collodion tubes. Since that time, a variety of different hemodialyzer configurations and membranes have been used. The purpose of this article is to provide a historical review of these various configurations and membranes. The rotating drum, coil, parallel flow, and hollow fiber artificial kidneys are discussed. Emphasis is placed on the factors that have influenced the shaping of the contemporary HD market.
Increasing the Proportion of Diabetics with AV Fistulas
Authors: Konner Klaus 
Published: March 2003

ABSTRACTWorldwide, older diabetic patients represent the most rapidly growing group of patients treated for end‐stage renal disease (ESRD). Preexisting arterial as well as venous problems have led to a pessimistic view on the creation of vascular access in this population. During 1993–98 I created all primary arteriovenous (AV) accesses for a total of 181 patients with diabetes mellitus (DM) ESRD and 567 patients with ESRD due to all other causes (non‐DM). The following approach led to good outcomes for both groups whether assessed by time to first intervention or time to failure: careful preoperative investigations for selection of adequate location for initial AV fistula through ultrasonographic techniques; timely surgical AV fistula creation; preference of large‐diameter, “healthy” arteries and veins, frequently requiring use of the elbow region; absolute priority for use of native vessels (i.e., avoidance of initial polytetrafluoroethylene [PTFE]); meticulous surgical technique and creativity; and continuous surveillance by the nephrologist and staff allowing elective revisions and avoidance of thrombosis. With this approach AV fistulas rather than PTFE grafts can be created in most diabetic and nondiabetic patients.
Fellows' Forum in Dialysis edited by Mark A. Perazella: A Case of Uremia‐Associated Pleural Effusion in a Peritoneal Dialysis Patient
Authors: Krishnan Mahesh , Choi Micheal 
Published: March 2003

ABSTRACTThe development of pleural effusions in ESRD patients is a relatively common occurrence. Uremia, currently a rare cause of effusion, can lead to the development of hemorrhagic pleural fluid collections in patients who are underdialyzed. Uremic pleural effusions should be considered when common etiologies of effusions such as volume overload, congestive heart failure (CHF), infection, and malignancy have been excluded. Uremia‐associated serosal injury allows transudation of fluid into the pleural space, and defective platelet function contributes to the hemorrhagic nature of the effusion. Although uremic effusions may occur less frequently in peritoneal dialysis patients, we present a patient who developed this complication due to a peritoneal dialysis regimen that was inadequate by current Dialysis Outcomes Quality Initiative guidelines. The pleural effusion resolved with an intensified dialysis regimen in the absence of a change in the underlying volume status.
Imaging in the dialysis patient: Dialysis Bone Disease
Authors: Adams Judith Elizabeth 
Published: March 2003

AbstractThe bone disease associated with end‐stage renal failure (ESRD) and treatment are complex and multifactorial, and has changed in both clinical and imaging features over the past three decades. Whereas previously features of vitamin D deficiency (rickets/osteomalacia) and intense, and prolonged, secondary hyperparathyroidism (bone resorption, osteosclerosis, metastatic calcification) predominated, these features are now rarely evident radiologically. This has occurred through the better understanding of vitamin D metabolism and improvements in therapeutic management. However, metastatic calcification in soft tissues and ‘‘adynamic’’ bone continue to be problematic. New complications have developed as a consequence of treatment (dialysis and transplantation), including amyloid deposition, noninfective sponyloarthropathy, osteonecrosis, and osteopenia/osteoporosis). Radiographs remain the most widely used imaging technique in examining for skeletal disease in patients with ESRD on maintenance dialysis. Occasionally, more sophisticated imaging (CT, MRI, nuclear medicine scanning) are helpful (parathyroid tumor localization, differentiation between infection and amyloid deposition). Developments in quantitative methods to assess bone density enable the effects of ESRD and treatment to be studied and monitored. Technical developments in computed tomography (rapid, multislice scanning) allow quantitation and monitoring of metastatic cardiac calcification in patients on hemodialysis, which has relevance to prognosis.
A Dialysis Case Presentation and Discussion Edited by Roger A. Rodby: Peritoneal Dialysis Catheter Replacement: “Save the Patient and Not the Catheter”
Authors: Piraino Beth 
Published: March 2003

AbstractA 63‐year‐old man on ambulatory peritoneal dialysis (APD) developed peritonitis with Enterococcus faecalis, treated with 2 g intraperitoneal (IP) vancomycin, with rapid clearing of the effluent white blood cells, but persistence of positive cultures. Vancomycin was redosed on day 8 (2 g IP), and then weekly. Gentamicin 140 mg IP loading dose, followed by 40 mg IP once a day was added after cultures were still positive at 2 weeks. The two drugs were continued for six additional weeks. Although the patient was asymptomatic, the effluent cultures continued to grow E. faecalis and the catheter was replaced 2 months after the onset of peritonitis. There was no evidence of either tunnel infection or intra‐abdominal abscess. Refractory peritonitis is defined as continuation of peritonitis after 5 days of appropriate therapy. This patient had persistently positive cultures but quickly became asymptomatic and signs of inflammation resolved readily. The most likely etiology appears to have been colonization of the slime layer of the intra‐abdominal portion of the catheter with the organism. The vancomycin dosing schedule may have played a role in the persistently positive cultures. A recent pharmacokinetic study suggested that patients on APD require 35 mg/kg IP of vancomycin as a loading dose, followed by 15 mg/kg IP once a day, given in a long day exchange. Simultaneous placement and removal as a single procedure was successful in this patient and can be done safely in patients whose effluent white blood cell count (WBC) is less than 100/mm3. Most patients can then be subsequently managed by doing supine dialysis (using a cycler) with decreased exchange volumes and a dry abdomen until healing occurs (usually 1–2 weeks). In this way hemodialysis can be avoided. By minimizing the effect on the patient's lifestyle, the patient is more likely to agree to a catheter exchange.