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C 1-x B x samples with 0 ≤ x ≤ 0.60 have been prepared by magnetron sputtering and ball milling. The effect of the boron concentration on the structure and performance of C-B samples as negative electrode materials in lithium and sodium cells were examined by X-ray diffraction and electrochemical methods. XRD experiments of all of the prepared samples show diffraction patterns characteristic of amorphous or nanostructured materials. The boron concentration was found to have a significant effect on the reversible capacity, initial coulombic efficiency and voltage of carbon electrodes. In lithium cells, the reversible capacities increase with increasing boron concentration for both sputtered and ball milled samples, however, the initial coulombic efficiency is lower than 80%. In Na batteries, boron has little effect on the reversible capacity and only increases the irreversible capacity and all electrodes have initial coulombic efficiencies that are lower than 40%. Crystallinity improvement of the C-B alloys structure is required for them to be of practical use in Na or Li cells.

A thin film binary library of carbon-rich Fe1-xCx (0.47 ≤ x ≤ 0.97) alloys was prepared by combinatorial sputtering of carbon and iron. The sputtered library was characterized by X-ray diffraction and room temperature 57Fe Mossbauer effect spectroscopy to determine its microstructure. X-ray diffraction results show that the Fe1-xCx film is amorphous in the whole composition range of the library. For 0.52 ≤ x ≤ 0.59, a hyperfine field distribution and a quadrupole splitting distribution as obtained from Mossbauer spectra indicate the presence of a ferromagnetic phase and a paramagnetic phase in this regime. With increasing of carbon content, for 0.61 ≤ x ≤ 0.97, the sextet disappears and two paramagnetic doublets splitting appear suggesting two different Fe sites. The electrochemical performance of the Fe1-xCx film was investigated in lithium cells and the presence of Fe was found to increase the reversible capacity per mass of carbon over that of a pure carbon electrode.

Carbon films were prepared by DC magnetron sputtering at various argon pressures ranging from 1 to 30 mTorr. The film sputtered at the lowest pressure (1 mTorr) was fully amorphous, showing no evidence of the (0 0 2) Bragg diffraction peak, and a density of 1.9 ± 0.3 g/cc, indicating little, if any, porosity. The film sputtered at the highest pressure (30 mTorr) showed a weak and broad (0 0 2) Bragg peak and had a density of 1.35 ± 0.15 g/cc, indicating significant porosity. The low pressure sputtered films were almost pure carbon (

Alloys of Fe1− x C x were produced using combinatorial sputtering methods. The composition of the films as a function of position was determined using electron microprobe techniques and the results have shown that a composition range of about 0.35

A test protocol to measure catalyst durability and OER activity through multiple simulated fuel cell start-up shut-down pulses has been developed. Data for NSTF-coated glassy carbon disks coated with platinum and platinum with an overlayer of IrRu are presented. A small amount of catalyst with high oxygen evolution activity deposited on platinum leads to a significant reduction in the potential an electrode will see during a transient start-up or shut-down pulses.

Thin films of Si1−xOx were produced using combinatorial sputtering methods. X-ray diffraction studies of these films show that they are amorphous or nanostructured. The effect of oxygen content on the electrochemical performance of these materials was studied. The reversible specific capacity (between 0.005 and 0.9 V) agrees with the assumption that Si1−xOx is made up of amorphous silicon, which can react to form Li3.75Si, and amorphous SiO2, which reacts to form Li4SiO4. The irreversible capacity increases with oxygen content when measured to a potential limit of 0.9 V vs Li/Li+ but further Li can be extracted from sites presumably near oxygen up to a potential of 2.0 V vs Li/Li+. However, such potentials for the negative electrode would not be reached in a full Li-ion cell. This work shows that the oxygen content in Si1−xOx should be optimized to produce materials with a reasonable active/inactive ratio in order to have electrodes with the desired specific capacity, an appropriate irreversible capacity and an appropriate amount of inactive phase to buffer volume expansion.

A comprehensive set of rotating disk electrode (RDE) tests has been developed to test the suitability of fuel cell catalyst candidates for use as either anode or cathode catalysts for transient conditions. The activity for Hydrogen Oxidation reaction (HOR), Oxygen Reduction reaction (ORR) and Oxygen Evolution reaction (OER) is tested together in one protocol. A total of 5 Pine Instruments RRDE test stations have been set up with automatic gas flow switching and computer software to control all aspects of the data collection process. The user simply sets up the electrochemical cell with a gas bubbler, reference electrode, counter electrode and sample and then selects a series of tests to be run. The software then switches gas flow, rotation rates and potentiostat set up files automatically. This infrastructure allows the rapid characterization of catalyst candidate materials. The series of tests is described, along with the purpose of each test in the protocol. As an example, the data collected from a Pt1−xHfx composition spread is presented. The optimal composition is found to be approximately 30 at.% Hf, when the ORR performance begins to decrease at a faster rate than the HOR performance and the OER current at 1300 mV is also a maximum. However, it was determined that from an applied point of view the drop in ORR performance was insufficient to adequately protect the cathode from the effects of the transient potentials during start-up of the fuel cell.

A Ru1-xIrx binary over-layer was deposited on Pt-coated nano-structured thin film from 3M Company. XPS measurements were used to confirm the composition of the over-layer. Rotating disk electrode measurements were used to assess oxygen evolution activity of the catalysts. The results showed that a low Ir/high Ru over-layer had a higher activity but lower stability than high Ir/low Ru samples.

Performance, cost and durability aspects of catalysts for proton exchange membrane fuel cells are discussed in the context of the US Department of Energy performance targets for automotive applications. State of the art catalysts are close to meeting the targets for these three important parameters. More work is required to further increase performance, reduce platinum loadings, and minimize the potentials the cathode catalyst can reach during adverse conditions such as those that will occur during fuel cell startup and shutdown

Intermixed Pt1-xNix (0 < x < 0.8) and Pt were sputter-deposited onto high surface area, NSTF-coated GC disks and studied for oxygen reduction reaction (ORR) activity by rotating disk electrode (RDE). NSTF-coated GC disks used in RDE experiments is a viable alternative to the regular mirror-polished GC disks in screening catalyst activities because both the catalytic activities and the effects of high-surface area support can be examined in a single measurement. The sputtered Pt-Ni samples have a much higher Surface Enhancement Factor (SEF) and kinetic current density. The impact of potential cycling is also included in this work.

Nanostructured thin film catalysts (NSTF) with widely varying compositions of PtxMyNz (M, N = Ni, Co, Zr, Hf, Fe, Mn) have been evaluated for 0 < x,y,z < 1. The catalysts' activity for oxygen reduction (ORR) was measured in 50 cm2 fuel cell membrane electrode assemblies. PtxNiy was found to be unique in showing an extraordinarily sharp peak in ORR activity as a function of the as-made composition around x=3, y=7. This composition gave a corresponding fcc lattice parameter of 3.71 Angstroms and a grain size of 7.5 nm. Both surface area and specific activity increases contribute to the increased mass activity. The ORR mass activity of the Pt3Ni7 is 60% higher than for the NSTF standard Pt68Co29Mn3 alloy.

The oxygen reduction activity of a series of Pt1-xCox catalysts (with high Co content) sputter-deposited onto 3M's nano-structured thin film support was measured with Rotating Disk electrode techniques. The activity was found to be much higher than that measured on Pt only. It was however not stable with repeated potential cycling. Ex-situ x-ray diffraction measurements of the disks during testing showed loss of bulk Pt from the lattice.

Layered Pt1-xIrx (0 < x < 0.3) and Pt films were sputtered onto mirror-polished and nano-structured thin film (NSTF)-coated GC disks. Rotating ring disk electrode studies of oxygen reduction reaction activity (ORR) were completed for all disks prepared. The NSTF-supported catalysts had much higher active surface area and reached the diffusion-limited current at a higher potential than the mirror-polished supported catalysts. The surface enhancement factor (SEF) of Pt on NSTF-coated disks was approximately 14. The SEF increased, (reaching a maximum of 22 at x = 0.2 in Pt1-xIrx) as the Ir content increased. The kinetic ORR current density also increased with increasing Ir content. A similar trend was not observed for catalyst coated, mirror-polished disks. All of the catalyst/support combinations had identical Tafel slopes and area specific current densities suggesting that the Pt is the active catalytic ingredient.

Protein adsorption on solid surfaces can be easily and accurately quantified by electron microprobe analysis using wavelength dispersive spectroscopy (WDS) to detect the carbon and nitrogen atoms within the protein. The method was calibrated by measurements of the carbon and nitrogen WDS signals for sputtered carbon and C0.72N0.28 films of known mass per unit area. Fibrinogen adsorption isotherms on silicon wafers and sputtered Ni film samples were studied using this method. The sensitivities for fibrinogen are about 20 ng/cm2 using carbon WDS, and about 60 ng/cm2 using nitrogen WDS with a circular electron beam of 50 μm diameter. The fibrinogen adsorption results on Si and Ni are in agreement with reported values in the literature. This study suggests that WDS studies are a reliable way to rapidly and automatically screen metallic biomaterials, including combinatorial libraries, in a quantitative manner for their protein affinity.

Squamous cell carcinomas of the head and neck {#article-title-2} Public awareness of this common form of cancer needs to be increased because despite important advances in treatment, prognosis still largely depends on the stage of presentation More than 90% of tumours in the head and neck are squamous carcinomas. Cancer of the head and neck, which can arise in several places, is often preventable, and if diagnosed early is usually curable. Unfortunately, patients often present with advanced disease that is incurable or requires aggressive treatment, which leaves them functionally disabled. We have reviewed current practice and potential future advances in the referral, diagnosis, and management of head and neck cancer. #### Summary points We gathered information from several sources, including personal experience of treating head and neck cancer in a multidisciplinary tertiary referral centre and the Medline and Cochrane databases. Squamous cell cancer of the head and neck is one of the most common cancers worldwide, with incidences of more than 30 per 100 000 population in India (oral cancer) and in France and Hong Kong (nasopharyngeal cancer). It constitutes about 4% of all cancers in the United States and 5% in the United Kingdom. A total of 2940 new cases of lip, mouth, and pharyngeal cancer in men were reported in the United Kingdom in 1996: an incidence of … Correspondence to: W Wei

In 1929 the dancer Isadora Duncan died from strangulation and carotid artery insult when her scarf caught in the wheels of a motor vehicle in which she was travelling. As part of the Edinburgh Festival scene, cycle propelled rickshaws are in popular use as short range taxis. The case is presented of a student who sustained a laryngeal rupture from strangulation with a scarf in the same way as Isadora. Despite an out of hospital cardiorespiratory arrest, severe laryngeal trauma, and carotid artery damage resulting in hemiparesis, the patient was successfully resuscitated and recovered with no neurological deficit. It is believed that this is the first recorded survival from this condition.

An approach to quantifying adsorbed protein layers at the protein/metal interface through spectroscopic ellipsometry using an in situ technique is described. A combinatorial binary Cu 1− x Al x (0 ≤ x ≤ 1) linear composition gradient was prepared by magnetron sputter deposition. Studies on composition spread libraries of samples allow the screening of multiple compositions at once, resulting in less measurement time, less preparation time, better systematic experiments, increased reliability of data, and the opportunity for better understanding of the impact of composition on protein adsorption. Using a custom-designed tubular flow cell, the metallic thin films were exposed to protein solutions of fibrinogen and albumin at two concentrations. The thickness of adsorbed protein layers was monitored dynamically by spectroscopic ellipsometry. It was found that both fibrinogen and albumin preferentially adsorbed onto Cu-rich surfaces, and for an Al content above ∼21 at.%, a significantly lower protein thickness was observed for both fibrinogen and albumin. These amounts depended greatly on the Al 2 O 3 content of the film surface, with a higher oxide content leading to a decreased protein thickness. Vastly different amounts of fibrinogen were found to adsorb on pure copper when measured using in situ or ex situ techniques due to a copper corrosion effect that occurs during ex situ measurements.

A clinical method of measuring 'hoarseness' is presented. Its value is assessed in 3 different types of vocal cord lesion and compared against normal values. There are shown to be significant differences between the normal and the abnormal voice and also differences between each type of vocal cord lesion. We feel that this quantification of hoarseness is useful in the treatment of patients as well as in monitoring their progress under therapy.

Systematic studies of protein adsorption onto metallic biomaterial surfaces are generally lacking. Here, combinatorial binary library films with compositional gradients of Ti(1-x)Cr(x), Ti(1-x)Al(x), Ti(1-x)Ni(x) and Al(1-x)Ta(x), (0

Several studies have found human papillomavirus virus (HPV) in tissue from head and neck squamous cell carcinomas (HNSCCs), although the number of positive cases varies greatly from study to study. The extent and molecular epidemiology of HPV in HNSCC were assessed within cases drawn from southeast Scotland by performing broad-spectrum, real-time HPV polymerase chain reaction (PCR) on DNA extracted from 100 cases of HNSCC in formalin-fixed, paraffin wax-embedded material. All HPV-positive specimens were genotyped and sampled by laser capture microdissection. Pure samples of tumour, and, where possible, dysplastic and normal epithelium were then submitted for further HPV PCR and genotyping to investigate the sensitivity of the technique in small tissue samples. 10 of 100 cases tested positive for HPV, with 8 of these being derived from Waldeyer's ring. HPV DNA was found in adjacent epithelium in two of four cases where this was available. These findings confirm that HPV is likely to be involved in a subset of HNSCC in this population and that successful amplification of HPV nucleic acid is possible even using small amounts of paraffin wax-embedded tissue.

More than 90% of head and neck tumours are squamous cell carcinomas. This review focuses on tumours arising from the mucosal surfaces of the upper aerodigestive tract. We discuss the aetiology, presentation and investigation of these tumours and give special attention to their management which may comprise surgical resection, chemoradiation or combined therapy. The surgical treatment of the clinically positive neck and the somewhat controversial topic of management of the N0 neck are also discussed.

The error frequency of uracil-initiated base excision repair (BER) DNA synthesis in human and Escherichia coli cell-free extracts was determined by an M13mp2 lacZ alpha DNA-based reversion assay. Heteroduplex M13mp2 DNA was constructed that contained a site-specific uracil target located opposite the first nucleotide position of opal codon 14 in the lacZ alpha gene. Human glioblastoma U251 and colon adenocarcinoma LoVo whole-cell extracts repaired the uracil residue to produce form I DNA that was resistant to subsequent in vitro cleavage by E. coli uracil-DNA glycosylase (Ung) and endonuclease IV, indicating that complete uracil-initiated BER repair had occurred. Characterization of the BER reactions revealed that (1) the majority of uracil-DNA repair was initiated by a uracil-DNA glycosylase-sensitive to Ugi (uracil-DNA glycosylase inhibitor protein), (2) the addition of aphidicolin did not significantly inhibit BER DNA synthesis, and (3) the BER patch size ranged from 1 to 8 nucleotides. The misincorporation frequency of BER DNA synthesis at the target site was 5.2 x 10(-4) in U251 extracts and 5.4 x 10(-4) in LoVo extracts. The most frequent base substitution errors in the U251 and LoVo mutational spectrum were T to GT to AT to C. Uracil-initiated BER DNA synthesis in extracts of E. coli BH156 (ung) BH157 (dug), and BH158 (ung, dug) was also examined. Efficient BER occurred in extracts of the BH157 strain with a misincorporation frequency of 5.6 x 10(-4). A reduced, but detectable level of BER was observed in extracts of E. coli BH156 cells; however, the mutation frequency of BER DNA synthesis was elevated 6.4-fold.

A retrospective case reference study examining the use of alcohol and tobacco in 303 women aged 40 or over suffering from oral or oropharyngeal cancer was conducted in the south-west Netherlands. Both alcohol and tobacco consumption are important in the development of oral and oropharyngeal cancer with increased consumption of both markedly increasing the risks of cancer, but alcohol having the greater effect.

The oxygen reduction activity of a series of Pt1-xCox catalysts (with high Co content) sputter-deposited onto 3M's nano-structured thin film support was measured with Rotating Disk electrode techniques. The activity was found to be much higher than that measured on Pt only. It was however not stable with repeated potential cycling. Ex-situ x-ray diffraction measurements of the disks during testing showed loss of bulk Pt from the lattice.

Pt and intermixed Pt 1-x Ni x (0.65 < x < 0.75) catalysts were sputtered-deposited onto both bare and nanostructured thin film (NSTF)-coated glassy carbon disks. The oxygen reduction reaction (ORR) activities of the disks were determined from Rotating Disk Electrode (RDE) measurements. Experiments on the NTSF-coated disks examined both catalytic activities and the effects of high surface area supports in a single measurement. The RDE measurement protocols were designed to examine changes in catalyst properties and performance during de-alloying and thus did not include the typical "electrochemical cleaning" procedure at the beginning. Instead, a continuous CV-ORR measurement protocol was used to monitor the electrochemical performance indicators such as active surface area (SEF) and ORR kinetic current density of the catalysts over the course of 9 h. As an example, the SEF of Pt 25 Ni 75 on the NSTF-support was initially 20 cm 2 P t /cm 2 planar and the SEF increased rapidly at the beginning of the experiment, then stabilized near ~50 cm 2 /cm 2 as Ni de-alloyed. This is compared with sputtered Pt on NSTF support that showed SEF ~15 cm 2 /cm 2 . De-alloying is an effective way to create Pt-transition metal catalysts on NSTF with extremely high active surface area.

Some patients complain of altered sensation in the mouth following nasal surgery. A prospective study of 60 consecutive patients who underwent a total of 83 intranasal procedures revealed that this was a common complication, particularly following submucous resection (SMR) or intranasal antrostomies.The area affected by painlparasthesia appears to be anatomically related to the surgical procedure(s) performed.

One year's experience of otolaryngological indicator operations is presented. Of 59 myringoplasties, 47 (79%) were successful; trainees performed 44 (74%) of the procedures. Seventy patients undergoing septal surgery reported significant improvements in nasal obstruction (P0.001), catarrh and facial pain (P0.005). Seventeen laryngectomies were performed for stage III and IV disease. The median operative time of 3.1 h rose to 5.1 h with a concomitant neck dissection. Eleven complications ensued, and the median stay for an uncomplicated laryngectomy was 16 days and 30 days following complications. Forty-one parotidectomies, 19 submandibular gland excisions and 10 ductal procedures were performed with 5 wound complications and 5 minor temporary facial nerve weaknesses. We have established a baseline for comparison of our practice with others and concluded that septal surgery gives good symptomatic relief, trainees perform reasonable numbers of myringoplasties, and improvements remain to be made in our outpatient septal surgery data collection.

Thin-film combinatorial sputter-deposited Sn-Cu-C alloys for negative electrodes of Li-ion batteries were characterized using electron microprobe (energy-dispersive spectroscopy), X-ray diffraction, electrochemical methods, and 119 Sn Mossbauer effect spectroscopy. Combinatorial libraries with nominal compositions Sn x Cu y C 1―x―y , with x = 0.49, x = 0.39, and x = 0.25 (0 < y < 1 - x) and Sn x Cu y C 1―x―y with y/x = 6/5 (0 < 1 ― x ― y < 0.45) were investigated. The addition of carbon was responsible for a decrease in grain size and an increase in specific capacity, which approached the calculated value (based on 4.4Li/Sn + 0.5Li/C). Mossbauer effect spectra were compared with differential capacity (dQ/dV vs V) and it was determined that the sample with the best capacity retention most closely resembled nanostructured Cu 6 Sn 5 grains embedded in a C matrix, yielding over 90% capacity retention after 30 cycles. However, changes in dQ/dV vs V suggested that regions of Cu 6 Sn 5 were steadily growing or aggregating as Li was cycled, which may be a limiting factor in later cycles.

A series of platinum-coated underlayer materials, alumina, gold, titanium carbide, and titanium disilicide, deposited by a high throughput magnetron sputtering method have been investigated as cathode catalyst supports in fuel cells. Orthogonal thickness gradients of the underlayer materials (0-100 nm planar equivalent) and the platinum top layer (0-75 nm planar equivalent) made up the 76 × 76 mm libraries. The resulting catalyst films were characterized by surface profilometry, X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. The electrochemical properties of the catalyst composition spreads were investigated simultaneously in 64-electrode proton exchange membrane fuel cells with emphasis placed on the determination of the electrochemical surface area (ECSA) as a function of underlayer thickness and chemistry. The present study shows that gold and titanium disilicide used as underlayers on 3M's nanostructured thin film supports lead to a loss of ECSA during operation. Migration and surface accumulation were observed when gold was used as underlayer material. For titanium disilicide, alloying and the generation of platinum silicide phases occurred. Alumina and titanium carbide were found to be potentially acceptable underlayer materials as well as alternative support materials on the basis of their influence on the catalyst surface area.

Layered Pt 1-x Ir x (0 < x < 0.3) and Pt films were sputtered onto 0.05 μm mirror-polished and nanostructured thin film (NSTF)-coated glassy carbon (GC) disks. Rotating disk electrode (RDE) studies of oxygen reduction reaction (ORR) activity were completed for all prepared disks. The Pt 1-x Ir x film was prepared by depositing alternating layers of Pt (constant thickness) and Ir (gradient), finished with a 5 nm Pt top layer. The NSTF-supported catalysts had much higher active surface areas and reached the diffusion-limited current at higher potentials than the bare GC supported catalysts. The surface enhancement factor (SEF) of Pt on NSTF-coated disks was approximately 14. The SEF increased (reaching a maximum of 22 at x = 0.2 in Pt 1-x Ir x ) as the Ir content increased for the Pt 1-x Ir x samples on NSTF. The kinetic ORR current density also increased with increasing Ir content. A similar trend was not observed for the same catalyst coated onto bare GC disks. All of the catalyst/support combinations had identical Tafel slopes and area-specific current densities, suggesting that Pt is the active catalytic ingredient. Catalysts coated on NSTF-coated GC disks can be used to accurately examine both catalytic activities and the effects of high surface area supports in a single measurement.

Sixty patients scheduled for septal surgery were assessed preoperatively with regard to their symptoms of nasal obstruction, catarrh and facial pain. They were scored on a linear analogue scale and then re-assessed two months postoperatively. There was a highly significant improvement in scores for all three symptoms (p less than 0.005).

The reaction of lithium with amorphous Si was studied by 119 Sn Mossbauer effect spectroscopy using small amounts of Sn as probe atoms. Two powder samples, amolphous-Si 87 Sn 13 and amolphous-Si 93 Sn 7 , were prepared by magnetron sputtering and investigated using in situ and ex situ Mossbauer spectroscopy. There are two gently sloping plateaus in the voltage vs capacity of Li/Si cells whose origin has never been explained. There is a clear step between these plateaus at ∼2.3 Li atoms per Si atom, or Li 2.3 Si. The step between the plateaus is found to correlate with dramatic changes in the Mossbauer effect spectra with x in Li x Si at x ≈ 2.3, which suggest the step occurs at the point when each Si atom is surrounded only by Li atom first neighbors. The changes in the Mossbauer spectra during the delithiation of the Li/Si-Sn cells also give clues about electrode failure mechanisms.

The effects of flaring and constricting the alar margins upon nasal airway resistance (NAR) were measured in 24 normal subjects. The median decrease in NAR on flaring was 21% whilst constricting increased NAR by a median of 67%, there being a high inter-subject variation. We feel these movements of the alar margin an important factor in controlling NAR.

Groups of thin-film transistors using a zinc tin oxide semiconductor layer have been fabricated via a combinatorial rf sputtering technique. The ZnO:SnO2 ratio of the film varies as a function of position on the sample, from pure ZnO to SnO2, allowing for a study of zinc tin oxide transistor performance as a function of channel stoichiometry. The devices were found to have mobilities ranging from 2to12cm2∕Vs, with two peaks in mobility in devices at ZnO fractions of 0.80±0.03 and 0.25±0.05, and on/off ratios as high as 107. Transistors composed predominantly of SnO2 were found to exhibit light sensitivity which affected both the on/off ratios and threshold voltages of these devices.

Transition metal oxides have been proposed as negative electrode material candidates for lithium-ion batteries because they can reversibly react with lithium via a displacement reaction to deliver two to three times the specific capacity of graphite. However, the practical application of transition metal oxides has been frustrated by their inconvenient working potential. Here, the impact of the addition of rare earth (RE) elements to transition metal (TM) oxides as negative electrodes was studied. Thin films of pseudobinary misch-metal-Fe-O libraries (misch metal is a mixture of common RE elements) were prepared by combinatorial sputtering methods. Powdered perovskite-structured RE-TM-O 3 samples, including LaFeO 3 , CeFeO 3 , and LaCoO 3 , were synthesized by solid-state methods. The structural and electrochemical characterizations of these samples are presented here. It was found that the addition of RE elements decreases the working potential of TM oxides. However, the specific capacity is undesirably lowered.

A review of recent literature on Si:C composite and nanocomposite electrode materials is first presented emphasizing that most authors do not compare the experimental specific capacity of the composite with that expected based on the phases present. We provide such a comparison and suggest that much of the apparent confusion in the literature, when taken as a whole, can be understood if nanocomposites prepared by "aggressive" methods like high energy milling and high temperature heat-treatment contain significant amounts of amorphous or nanocrystalline SiC. In order to help resolve the confusion, samples of Si 1-x C x were prepared by high-energy mechanical milling for 0.25 < x < 0.5 and by combinatorial co-sputtering for 0 < x < 0.8. X-ray diffraction shows the mechanically milled samples to be a mixture of nanocrystalline SiC and Si. Electrochemical studies of the mechanically milled samples show that the attained specific capacity can be described accurately assuming that the Si is active and can reversibly react with 3.75 Li atoms per Si atom (Li 15 Si 4 ), while the SiC is inactive. The co-sputtered samples are amorphous or extremely nanostructured for all x. For 0 < x < 0.5, the specific capacity decreases with increasing x, from about 3580 mAh/g at x = 0, to about 1000 mAh/g at x = 0.5, presumably due to the formation of inactive regions of a-SiC. The capacity of the co-sputtered samples does not reach small values at x = 0.5, unlike the ballmilled samples, because there are presumably some regions of a-Si and a-C among the inactive a-SiC regions due to the high quenching rate of the sputtering process. Commercially relevant compositions are identified.