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Objectives: To review the management and outcome of patients with malignant neoplastic disease of the parotid lymph nodes excluding those with primary salivary gland tumors.Study Design: Retrospective review of 14 patients who had malignant parotid lymph nodes from metastatic cutaneous malignancies, direct extension from primary cutaneous malignancies, or lymphoproliferative disorders.Methods: Charts were reviewed from three institutions and tabulated for age, gender, histopathology, treatment, and outcome.Results: Fourteen patients met the criteria for study. Ten patients had neoplastic nodes from cutaneous malignancies. Seven involved squamous cell carcinoma, two were metastatic from melanoma, and one was metastatic from basal cell carcinoma. Four patients had involvement from lymphoproliferative disorders.Conclusions: Metastatic disease to the parotid nodes or direct extension to nodes from primary cutaneous malignancy demonstrates a poor prognosis in this series. Prognosis of lymphoproliferative disorder is more favorable. [ABSTRACT FROM AUTHOR]

The high brightness, low emittance electron beams achieved in modern X-ray free-electron lasers (XFELs) have enabled powerful X-ray imaging tools, allowing molecular systems to be imaged at picosecond time scales and sub-nanometer length scales. One of the most promising directions for increasing the brightness of XFELs is through the development of novel photocathode materials. Whereas past efforts aimed at discovering photocathode materials have typically employed trial-and-error-based iterative approaches, this work represents the first data-driven screening for high brightness photocathode materials. Through screening over 74 000 semiconducting materials, a vast photocathode dataset is generated, resulting in statistically meaningful insights into the nature of high brightness photocathode materials. This screening results in a diverse list of photocathode materials that exhibit intrinsic emittances that are up to 4x lower than currently used photocathodes. In a second effort, multiobjective screening is employed to identify the family of M 2 O (M = Na, K, Rb) that exhibits photoemission properties that are comparable to the current state-of-the-art photocathode materials, but with superior air stability. This family represents perhaps the first intrinsically bright, visible light photocathode materials that are resistant to reactions with oxygen, allowing for their transport and storage in dry air environments., (© 2021 Wiley-VCH GmbH.)

Achieving a low mean transverse energy or temperature of electrons emitted from the photocathode-based electron sources is critical to the development of next-generation and compact x-ray free electron lasers and ultrafast electron diffraction, spectroscopy, and microscopy experiments. In this Letter, we demonstrate a record low mean transverse energy of 5 meV from the cryo-cooled (100) surface of copper using near-threshold photoemission. Further, we also show that the electron energy spread obtained from such a surface is less than 11.5 meV, making it the smallest energy spread electron source known to date: more than an order of magnitude smaller than any existing photoemission, field emission, or thermionic emission based electron source. Our measurements also shed light on the physics of electron emission and show how the energy spread at few meV scale energies is limited by both the temperature and the vacuum density of states.

A theoretical development of prior analyses, together with our solenoid scan measurements on eight planar metal photocathodes (Ag, Be, Cr, Cu, Mo, Sn, Ta, and W) and previous data on Mg [X. J. Wang, M. Babzien, R. Malone, and Z. Wu, in Proceedings of LINAC2002, Gyeongju, Korea, 2002 (Pohang Accelerator Laboratory, Pohang, Korea, 2002), pp. 142-144.] indicate that the transverse momentum (and hence intrinsic emittance) of an electron beam is fundamentally dependent on the electron effective mass in the metal.

We present a characterization of the performance of an ultrashort laser pulse driven DC photoelectron gun based on the thermionic emission gun design of Togawa et al. [Togawa, K., Shintake, T., Inagaki, T., Onoe, K. & Tanaka, T. (2007). Phys Rev Spec Top-AC 10, 020703]. The gun design intrinsically provides adequate optical access and accommodates the generation of approximately 1 mm2 electron beams while contributing negligible divergent effects at the anode aperture. Both single-photon (with up to 20,000 electrons/pulse) and two-photon photoemission are observed from Ta and Cu(100) photocathodes driven by the harmonics (approximately 4 ps pulses at 261 nm and approximately 200 fs pulses at 532 nm, respectively) of a high-power femtosecond Yb:KGW laser. The results, including the dependence of the photoemission efficiency on the polarization state of the drive laser radiation, are consistent with expectations. The implications of these observations and other physical limitations for the development of a dynamic transmission electron microscope with sub-1 nm.ps space-time resolution are discussed.

Thermal lens shaping for astigmatism compensation is extended to a high-power, diode-pumped, Yb:KGW laser by employing a gain crystal geometry designed for efficient polarized pumping. The 63MHz oscillator is soliton mode-locked with the aid of a saturable Bragg reflector to yield 250fs (347fs) pulses at an output power of 3.5W (5W). Frequency doubling of the 250fs pulses with an intrinsic efficiency >60% provides 1.65W of average green power.

A high-resolution, flat-field, plane-grating, f/10 spectrometer based on the novel design proposed by Gil and Simon [Appl. Opt. 22, 152 (1983)] is demonstrated. The spectrometer design employs off-axis parabolic collimation and camera mirrors in a configuration that eliminates spherical aberrations and minimizes astigmatism, coma, and field curvature in the image plane. In accordance with theoretical analysis, the performance of this spectrometer achieves a high spatial resolution over the large detection area, which is shown to be limited only by the quality of its optics and their proper alignment within the spatial resolution of a 13 microm x 13 microm pixelated CCD detector. With a 1500 lines/mm grating in first order, the measured spectral resolving power of lambda/Dlambda = 2.5(+/-0.5) x 10(4) allows the clear resolution of the violet Ar(I) doublet at 419.07 and 419.10 nm.

In order to compare patterns of resistance to inhibition by clavulanic acid with patterns of resistance to inhibition by a beta-lactamase inhibitor protein (BLIP), R164S, R244S, and R164S/R244S mutant forms of TEM beta-lactamase were prepared by site-directed mutagenesis. When kinetic parameters were determined for these mutant and wild-type forms of TEM, the single mutants showed properties that were similar to those in the literature but the double mutant showed properties that were very different. The R164S/R244S double mutant form of TEM retained its resistance to inhibition by clavulanic acid (characteristic of the R244S mutation) but lost all its ability to hydrolyze ceftazidime (characteristic of the R164S mutation). While these characteristics are contrary to those previously reported for an R164S/R244S double mutant, this discrepancy resulted from the use of a defective mutant in the earlier study. Both the single and double mutant forms of TEM remained highly sensitive when tested for inhibition by BLIP, showing only slightly increased resistance compared to that of the wild type; this pattern of resistance is quite different from the pattern of clavulanic acid resistance. The slight increases in resistance to inhibition by BLIP seen in the mutants may have been related to the fact that all of the mutations effected changes in the net charge on the TEM protein that could impede interactions with BLIP.

Extensive fungal infections of the paranasal sinuses are most often associated with immunocompromised patients or poorly controlled diabetics. Seldom do young, otherwise healthy patients present with advanced disease destroying bone and compressing the dura and frontal lobe posteriorly. A case of eosinophilic fungal rhinosinusitis which grew Curvularia lunata in culture is reported. Bone destruction can be common as an expanding inflammatory mass pushes and weakens surrounding bone. The destruction of the frontal sinus with the compression of the dura into the anterior cranial fossa of a 26-year-old requires drainage, reconstruction, and medical management. Our experience with the disease and our approach is reviewed.

Use of a transverse KD?P Pockels cell and novel low-loss sapphire Rochon polarizer to cavity dump a hard-aperture, Kerr-lens mode-locked, Ti:sapphire oscillator is demonstrated. High-quality 90-fs pulses with energies of ~50 nJ at repetition rates of up to 50 kHz were obtained.

We describe the design of a continuously tunable Ti:sapphire regenerative amplifier that is capable of sustaining amplification over a wavelength range from 730 nm to more than 800 nm. The amplifier cavity is tuned with a prism pair in combination with a spherical mirror. It sustains an oscillation bandwidth of 5 nm and produces a chirped output pulse energy of 1.2 mJ compressible to a duration of 140 fs at 745 nm. We present a calculation of the theoretical bandwidth.

Measurements of 160-fs, 248-nm ultrashort pulses are obtained through a two-photon fluorescence measurement based on the two-photon-induced color-center fluorescence in fused-silica crystals. The method proved to be reliable and advantageous in comparison with two-photon fluorescence techniques employing other materials, both solid state and gaseous.

Carotenoids occur universally in photosynthetic organisms but sporadically in nonphotosynthetic bacteria and eukaryotes. The primordial carotenogenic organisms were cyanobacteria and eubacteria that carried out anoxygenic photosynthesis. The phylogeny of carotenogenic organisms is evaluated to describe groups of organisms which could serve as sources of carotenoids. Terrestrial plants, green algae, and red algae acquired stable endosymbionts (probably cyanobacteria) and have a predictable complement of carotenoids compared to prokaryotes, other algae, and higher fungi which have a more diverse array of pigments. Although carotenoids are not synthesized by animals, they are becoming known for their important role in protecting against damage by singlet oxygen and preventing chronic diseases in humans. The growth of aquaculture during the past decade as well as the biological roles of carotenoids in human disease will increase the demand for carotenoids. Microbial synthesis offers a promising method for production of carotenoids.

Tonsillectomy remains one of the most common surgical procedures performed in the world. One of the most significant complications is postoperative hemorrhage. Though most bleeding often can be controlled with local anesthesia in an office or emergency room, some patients require return to the operating room for general anesthesia to control the hemorrhage. A ten-year retrospective study was done to review patients who required return to the operating room for general anesthesia for control of hemorrhage. Variables investigated include age, gender, time of surgery, onset of hemorrhage, season of the year, and the amount of blood loss noted during initial surgery. Seven of the 756 patients (.93%) required a second general anesthesia to control hemorrhage. Seasonal and gender predilictions are noted in this study. Recent trends in tonsillectomy are reviewed. Postoperative hemorrhage creates anxiety, prolongs morbidity, and increases health care cost. Limiting this complication is clearly in the best interest of both patient and surgeon.

Carotenoids have recently received considerable interest because of their potential in delaying or preventing degenerative diseases such as arteriosclerosis, cancer, and aging. In this study we show that the active oxygen species singlet oxygen (1O2) and peroxyl radicals differently affect carotenoid composition and biosynthesis in the yeast Phaffia rhodozyma. Photochemical generation of 1O2 with rose bengal or alpha-terthienyl induced carotenoid accumulation. In contrast, peroxyl radicals derived from t-butylhydroperoxide (tBOOH) or H2O2 decreased the content of astaxanthin and increased beta-carotene by approximately 4-fold, suggesting end product feedback regulation by astaxanthin or inhibition of biosynthetic enzymes. 14C labeling of carotenoids during oxidative stress supported the possibility of end product regulation. Carotenoids were bleached by 8 mM tBOOH within 6 h when carotenogenesis was inhibited by thymol. When treated with peroxides, a previously unreported pigment in P. rhodozyma was formed. The carotenoid had a mass of 580 Da and a molecular formula of C40H52O3. Chemical derivatizations combined with mass and absorbance spectroscopy tentatively identified the carotenoid as dehydroflexixanthin (3,1'-dihydroxy-2,3,3',4'-tetradehydro-1',2'-dihydro-beta,psi-caro tene-4-one). This study provides the first report of induction of astaxanthin biosynthesis by 1O2, probable feedback control by astaxanthin, and the oxidative degradation of astaxanthin to novel pigments in P. rhodozyma.

Background: Conchal defects secondary to surgical procedures or trauma often cannot be closed primarily., Objective: Tissue transfer for closure of defects must be tension free and not create a postauricular sulcus too shallow., Methods: A retroconchal island flap provides such a closure. A rhomboid transposition flap used to provide closure of the donor site retains the depth of the posterior sulcus., Results: The closure of the defect heals well within 4-6 weeks even in presence of scar tissue from multiple prior surgeries., Conclusion: The retronconchal island flap is a simple, reliable technique to close the defect of the concha without sacrificing the natural depth of the posterior sulcus.

Myringotomy with placement of ventilation tubes is the most common pediatric otolaryngologic procedure in the United States. Otorrhea is generally recognized as the most common complication of this procedure. The current study is a three-year prospective evaluation of post tympanostomy otorrhea to determine what variables might be associated with otorrhea. Analysis of patients from a predominantly rural population is presented.

Malignant melanoma is most commonly associated with cutaneous malignancies of sun-exposed skin, but melanoma also occurs in the mucosal surfaces of the head and neck. The symptoms of intranasal melanoma are most often associated with benign conditions that patients often ignore during the early course of the disease. Benign symptoms that persist require thorough evaluation to exclude neoplastic disease in which timely diagnosis and early treatment offers the best prognosis.

We observe an order-of-magnitude enhancement of the photorefractive effect in undoped CdTe on ~1-ps time scales that is caused by an overshoot in the two-photon-produced Dember space-charge field associated with hot-carrier transport.

The photorefractive nonlinearity associated with the Dember space-charge field between electrons and holes produced by two-photon absorption is unambiguously isolated and studied in undoped CdTe by using a nondegenerate, forward-probing, polarization-sensitive, transient-grating technique with a temporal resolution of <5 ps.

A novel transient-grating geometry, which is nondegenerate, copropagating, phase matched, and polarization sensitive, is used to isolate and measure independently the ultrafast dynamics of multiple coexisting gratings in GaAs:EL2 with a temporal resolution of <5 psec. This technique permits the measurement of the evolution of the photorefractive grating in materials with zinc blende symmetry, where the photorefractive grating is usually obscured by the stronger free-carrier and instantaneous bound-electronic gratings.

Restriction endonuclease analysis was used to detect alpha-gene deletions and to determine the haplotypes in the DNA of the beta S-gene-cluster [Benin, Central African Republic (CAR), and Senegal] in 221 patients with sickle cell anemia (SS). The clinical expression of SS was modified by the beta S-gene-cluster polymorphisms and the alpha-gene status (alpha-thalassemia-2). The overall risk of soft tissue organ failure caused by the obliterative sickle vasculopathy (including stroke, renal failure, chronic lung disease with cor pulmonale, leg ulcers, and young adult death) was increased threefold in those with a CAR haplotype and was decreased in those with a Senegalese chromosome (p = 0.003). In the presence of a Senegalese haplotype, the patient's health is better, and with the CAR haplotype it is always worse. With the Benin, it is intermediate. Acute recurrent clinical events including hospitalized sickle cell crisis, bone infarction, and infection are decreased in frequency in those with a Senegalese haplotype. The risk of most acute events including acute chest syndrome is equivalent in those with Benin or CAR haplotypes. In the United States, alpha-thalassemia-2 is co-inherited randomly among the beta S-gene-cluster haplotypes. Acute events occurring during childhood are minimally effected by this co-inheritance. The risk of soft tissue organ failure is decreased. After the age of 20 years, painful episodes of the lumbar dorsal area are increased in patients who had alpha-thalassemia-2 in association with degenerative bone disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Two sons of a previously reported Ghanaian homozygote for the hereditary persistence of fetal hemoglobin (HPFH) (Ringelhann et al., 1970) also are HPFH homozygotes. In addition, another unrelated adult Ghanaian homozygote has been detected. All of these Ghanaian homozygotes as well as three American Black HPFH homozygotes have the G gamma A gamma type of HPFH with a G gamma to A gamma ratio of about 3:2, in contrast to an Asiatic Indian homozygote who has the G gamma type. Globin chain synthesis in HPFH homozygotes is unbalanced, with a gamma/alpha ratio of 0.6 or less, whereas it is balanced in heterozygotes according to most reports.

After a boy of Mexican-American descent became jaundiced during treatment of a serious urinary tract infection with an oxidant drug, an extensive hematological examination was made. The important finding was the presence of Hb-Leiden to the extent of less than 3% or about a tenth of the usual percentage. Although inclusion bodies are present in the erythrocytes at all times, his hematological parameters have remained normal. The genetic basis for the unusually small amount of Hb-Leiden in the propositus may be due to the Hb-Leiden gene in an anti-Lepore configuration, that is, and Hb-Leiden gene in cis to the normal beta and delta genes.

The microchromatographic procedure for the quantitative analysis of the hemoglobin components in a hemolysate uses columns of DEAE-cellulose in a plastic drinking straw with a glycine-KCN-NaCl developer. Not only may the method be used for the quantitative analysis of Hb-F but also for the analysis of the varied components in mixtures of hemoglobins.

The postnatal switch from hemoglobin (Hb) F to Hb A in the baboon (Papio cynocephalus) occurs somewhat more rapidly than in humans. Minor components which are related to Hb F and Hb A are also present and show reciprocal rise and fall. The baboon produces two types of gamma chain presumably from nonallelic genes. These have either an isoleucyl (I gamma) or a valyl (V gamma) residue in position 75. As in the human case with G gamma and A gamma chains, the ratio I gamma to V gamma chains changes during the postnatal switch. Production of Hb F in the baboon may be stimulated by phenylhydrazine or more effectively by 5-azacytidine. With phenylhydrazine, the ratio of I gamma to V gamma chains in the Hb F is the same as in the traces of Hb F in the juvenile or adult baboon. However, with 5-azacytidine, at least some of the Hb F that is produced probably has been synthesized with an I gamma to V gamma ratio that is present prenatally and in the newborn baboon.

A description is given of the nature of column packings for reverse phase high performance liquid chromatography (HPLC) and of the equipment that is available for HPLC procedures. HPLC methods have been applied to the identification of abnormal hemoglobins. In most instances, the variant peptide(s) is easily detected on the chromatogram. The effect of differences in column packings and developer sequences is described; modifications in either provide many means for achieving desired separations. Thus, HPLC separates peptides well and is a rapid, sensitive method for studying hemoglobin. Although the emphasis has been on the examination of peptides of abnormal hemoglobins, the procedure can be extended to other aspects such as the separation of hemoglobin chains themselves.

Accurate specific diagnosis of sickle cell disease can now be made at birth on routinely obtained cord blood samples by microcolumn chromatography. The method uses a small column of a cation ion exchange resin, CM-Sephadex, and a single developer that allows definitive rapid distinction of hemoglobin SS, AS, AC, SC, and CC, within two hours. Seventy-five samples or more per day have been analyzed by one technician in a laboratory without special precautions or equipment. In a program which has been initiated on a large, totally unpredictable obstetrical service in Los Angeles, 10,401 consecutively born infants have been studied for hemoglobin type without regard to racial origin. Three SS infants, 1 SC, 143 AS infants, and 37 AC infants as well as several with other abnormal hemoglobins have been identified without interfering with the routine operation of the delivery rooms of the obstetrical service. The diagnosis of sickle cell disease has been confirmed on subsequent examinations of the infants. The feasibility of using microcolumn chromatography as a rapid, accurate, inexpensive, and easy method for the rapid diagnosis of sickle cell disease in newborns has now been established.

The human gamma-chain variants are discussed in relation to their chemical structures and to the importance that their study has had for our present knowledge of the genetics and biosynthesis of hemoglobin chains.

We evaluate the performance of a novel 10-Hz picosecond Nd:YAG regenerative amplifier configured as a selffiltering unstable resonator. Pulse energies of ~60 mJ in ~100 psec at 1.06 microm are achieved using a single 6-mm-diameter Nd:YAG rod, while mode-matching requirements are minimized.