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From 2014–2019, 8 juvenile black bears ( Ursus americanus) from different geographic regions were presented to the California Department of Fish and Wildlife because of emaciation, alopecia, and exfoliative dermatitis that resulted in death or euthanasia. Autopsy and histopathology revealed that all 8 bears had generalized hyperkeratotic dermatitis, folliculitis, and furunculosis. Skin structures were heavily colonized by fungal hyphae and arthrospores; fungal cultures of skin from 7 bears yielded Trichophyton equinum, a zoophilic dermatophyte reported only rarely in non-equid species. Additional skin conditions included mites (5), ticks (2), and coagulase-negative Staphylococcus sp. infections (2). No other causes of morbidity or mortality were identified. Molecular comparisons performed at the University of Texas Fungal Reference Laboratory determined that all isolates produced identical banding patterns, potentially representing a clonal population. Dermatophytosis is commonly localized and limited to the stratum corneum of the epidermis and hair follicles. Generalized disease with dermal involvement is rare in immunocompetent individuals; illness, malnutrition, age, or immunosuppression may increase susceptibility. Underlying causes for the severe disease impact in these bears were not evident after physical or postmortem examination. The mechanism by which bears from different geographic locations had severe, T. equinum–associated dermatophytosis from a potentially clonal dermatophyte could not be explained and warrants further investigation.

In March 2017, 26 American goldfinches (Spinus tristis) were found dead following a drench application of imidacloprid in California (USA). Identical seed fragments were present in the digestive tracts. Imidacloprid was detected in 4 separate pooled samples from 18 birds, in crop/gizzard contents (4.8 ± 1.3 ppm; range 2.2–8.5 ppm) and liver tissues (3.9 ± 0.6 ppm; range 2.1–4.8 ppm). We suspect that fallen elm (Ulmus sp.) seeds were contaminated with imidacloprid during the drench application and subsequently ingested, resulting in acute toxicity and death. Environ Toxicol Chem 2019;38:1724–1727. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.

The ability to rapidly detect and respond to wildlife morbidity and mortality events is critical for reducing threats to wildlife populations. Surveillance systems that use pre-diagnostic clinical data can contribute to the early detection of wildlife morbidities caused by a multitude of threats, including disease and anthropogenic disturbances. Here, we demonstrate proof of concept for use of a wildlife disease surveillance system, the ‘Wildlife Morbidity and Mortality Event Alert System’, that integrates pre-diagnostic clinical data in near real-time from a network of wildlife rehabilitation organizations, for early and enhanced detection of unusual wildlife morbidity and mortality events. The system classifies clinical pre-diagnostic data into relevant clinical classifications based on a natural language processing algorithm, generating alerts when more than the expected number of cases is recorded across the rehabilitation network. We demonstrated the effectiveness and efficiency of the system in alerting to events associated with both common and emerging diseases. Tapping into this readily available unconventional general surveillance data stream offers added value to existing wildlife disease surveillance programmes through a relatively efficient, low-cost strategy for the early detection of threats.

Purpose: The purpose of this study was to objectively assess the optical vision quality of patients before and after Nd:YAG capsulotomy for posterior capsular opacification using a double-pass retinal imaging system. Methods: We retrospectively analyzed the data from 26 pseudophakic eyes with posterior capsular opacification that underwent Nd:YAG capsulotomy. The objective scatter indices, modulation transfer function cutoff frequencies, Strehl ratios, and logMAR corrected distance visual acuities were assessed before and after YAG capsulotomy with a double-pass retinal imaging system (OQAS II, Visiometrics, Spain). We also analyzed data from a subgroup of 10 patients with pre-YAG corrected distance visual acuity of 0.10 logMAR (20/25) or better. Results: Vision quality indices improved in all 26 eyes, resulting in a statistically significant improvement in the corrected distance visual acuity (p=0.007), objective scatter index (p=0.001), modulation transfer function cutoff frequency (p=0.001), and Strehl ratio (p=0.020). The overall mean improvements included 0.12 ± 0.04 logMAR for corrected distance visual acuity, 2.84 ± 0.76 for objective scatter index, 12.29 ± 2.77 for modulation transfer function cutoff frequency, and 0.06 ± 0.03 for Strehl ratio. Our sub-analysis of 10 eyes with 0.10 logMAR (20/25) corrected distance visual acuity or better also showed a statistically significant improvement in the mean objective scatter index (0.76 ± 16; p=0.001), resulting in approximately 35% decrease in intraocular light scatter. Conclusions: The objective vision quality measurements as assessed by the double-pass retinal imaging system showed a significant improvement after YAG capsulotomy. This suggests that the objective scatter index improves after YAG capsulotomy, even in eyes with pre-YAG 0.10 logMAR (Snellen 20/25) corrected distance visual acuity or better. RESUMO Objetivo: Avaliar objetivamente a qualidade da visão óptica antes e depois da capsulotomia com Nd: YAG, obtida por imagem pelo metodo de dupla passagem de luz em pacientes com opacificação capsular posterior. Método: Análise retrospectiva de 26 olhos pseudofácicos com opacificação capsular posterior visualmente significativa, que foram submetidos à capsulotomia de Nd: YAG. O índice de dispersão objetiva, a função de transferência de modulação, a relação de Strehl e a acuidade visual à distância corrigida foram avaliados antes e após a capsulotomia com YAG usando o dupla passagem de luz (OQAS II, Visiometrics, Espanha). Também foi analisado um subgrupo de pacientes com acuidade visual à distância corrigida pré-YAG de 0,10 logMAR (20/25) ou melhor. Resultados: Os índices de qualidade da visão melhoraram em todos os 26 olhos, resultando em uma melhora estatisticamente significativa na acuidade visual à distância corrigida (p=0,007), índice de dispersão objetiva (p=0,001), função de transferência de modulação (p=0,001) e relação de Strehl (p=0,020). A melhora média na acuidade visual à distância corrigida foi de 0,12 ± 0,04 logMAR, no índice de dispersão objetiva foi de 2,84 ± 0,76, no função de transferência de modulação foi de 12,29 ± 2,77 e na razão de Strehl foi de 0,06 ± 0,03 em todos os olhos. Sub-análise de 10 olhos com 0.10 logMAR (20/25) acuidade visual à distância corrigida ou melhor também mostrou uma melhora estatisticamente significativa no índice de dispersão objetiva (p=0,001). A melhora média no OSI foi de 0,76 ± 16, uma diminuição de 35% na dispersão da luz intraocular. Conclusões: A qualidade da visão avaliada pelo dupla passagem de luz mostra uma melhora significativa nas medidas objetivas da qualidade da visão após a capsulotomia do YAG. O índice de dispersão objetiva melhora após a capsulotomia YAG, mesmo em olhos com acuidade visual à distância corrigida pré-YAG de 0,10 logMAR (Snellen 20/25) ou melhor.

A hatch-year Swainson’s Hawk (Buteo swainsoni) recovered from Modoc County, California, US, on 12 August 2012 had malformations of the rear limbs consisting of bilateral polymelia and syndactyly. We describe the malformations and evaluate potential causes. Postmortem examination revealed varus rotation of both femurs and abnormal appendages originating from the distal medial surface of the tibiotarsi with two nonfunctional digits on the right leg and one digit on the left leg. There was syndactyly between digits III and IV of both feet. Avian pox viral dermatitis was present on the skin of the ventral abdomen. A definitive cause of the skeletal malformations was not identified.

Author(s): Rudd, Jaime L.; McMillin, Stella C.; Kenyon, Marc W., Jr.; Clifford, Deana L.; Poppenga, Robert H. | Abstract: In 2016, the Wildlife Investigations Lab initiated a statewide mountain lion health surveillance study to understand population health and anticoagulant rodenticide (AR) exposure. Exposure to first-generation (FGARs) and second-generation (SGARs) anticoagulant rodenticides are common in predators such as raptors, wild canids (i.e., foxes and coyotes) and bobcats. However, statewide data regarding rodenticide exposure in these species, including mountain lions, have been limited. Our objectives were to determine the statewide prevalence and geographic distribution of AR exposure in necropsied mountain lions. We used liquid chromatography/mass spectroscopy to detect rodenticides in liver samples from 111 (77 male: 34 female) mountain lion carcasses from 37 counties that died between Feb 2016 and Feb 2017. Necropsied carcasses were lions taken on depredation permits, vehicular strike, public safety, or other reasons. Overall, we detected ARs from the liver tissue of mountain lions from 35 counties with 105 of the 111 (94.5%) lions having exposure. We detected FGARs in 81 individuals (73%) from 33 counties and SGARs in 102 individuals (92%) from 35 counties. Seventy-eight individuals (70%) were exposed to both SGARs and FGARs while 6 (5%) individuals had no detectable AR concentration. Of the FGARs detected, diphacinone was the most common and was observed in 67% of sampled individuals. Brodifacoum was the most common SGAR, detected in 90% of sampled individuals. Exposure to FGARs was correlated with exposure to SGARs (χ2 = 5.8, p = 0.01). Exposure to ARs was not associated with lower body condition score. Although our study represents only one year of data, we demonstrate that exposure to both FGARs and SGARs is widespread in California’s mountain lions. We recommend continued AR screening of livers from mountain lion carcasses to further enhance our understanding about the relative contributions they may have on population health. Continued monitoring would also measure the effectiveness of regulatory changes intended to reduce non-target wildlife exposure to rodenticides

Author(s): McMillin, Stella C.; Poppenga, Robert H.; Chandler, Shannon C.; Clifford, Deana L. | Abstract: Anticoagulant rodenticides (ARs) are used to control rodents around homes, buildings, and in agriculture. They have been found widely in predatory and scavenging wildlife as a result of secondary exposure and less commonly in herbivores and omnivores from primary exposure. While predators and scavengers have been monitored for AR exposure, very little information is available about AR residues in edible muscle tissue of game animals. Game animals may be exposed to ARs through direct consumption of bait, ingestion of contaminated food or vegetation, or consumption of contaminated prey items. Carcasses of three species of game animals (black bear, wild pigs, and mule deer) were collected opportunistically for this study from 2013 to 2015. Causes of death were mainly depredation, vehicular trauma, or hunter harvest. Sampling was performed in the field by California Department of Fish and Wildlife and US Department of Agriculture Wildlife Services staff. Tissues were analyzed for 37 deer in 11 counties, 120 wild pigs in 10 counties, and 12 bears in eight counties. The highest prevalence of AR exposure was found in bears, with 83% of tested livers containing ARs. Bear were most likely to be exposed to brodifacoum, a second generation AR used primarily in and around residences. Prevalence of exposure in wild pigs was 8.3%. Pigs were most likely to be exposed to chlorophacinone, used primarily in agriculture. More than half of pigs with AR residues in their liver also had AR residues in their muscle tissue. There were no AR detections in muscle samples tested for bears with AR residues in liver. None of the deer livers tested positive for ARs.

In September 2007, Lake Davis (near Portola, California) was treated by the California Department of Fish and Game with CFT Legumine, a rotenone formulation, to eradicate the invasive northern pike (Esox lucius). The objective of this report is to describe the fate of the five major formulation constituents-rotenone, rotenolone, methyl pyrrolidone (MP), diethylene glycol monethyl ether (DEGEE), and Fennedefo 99-in water, sediment, and brown bullhead catfish (Ameiurus nebulosus; a rotenone-resistant species) by determination of their half-lives (t(1/2)) and pseudo first-order dissipation rate constants (k). The respective t(1/2) values in water for rotenone, rotenolone, MP, DEGEE, and Fennedefo 99 were 5.6, 11.1, 4.6, 7.7, and 13.5 d; in sediments they were 31.1, 31.8, 10.0, not able to calculate, and 48.5 d; and in tissues were 6.1, 12.7, 3.7, 3.2, and 10.4 d, respectively. Components possessing low water solubility values (rotenone and rotenolone) persisted longer in sediments (not detectable after 157 d) and tissues (

This article presents qualitative research exploring how one consumer group, urban teenagers 14–15 years old, in four global cities — Johannesburg (South Africa), Bangalore (India), Munich (Germany), and New York (United States) — articulate and negotiate their identities on the ground. It takes into account the transnational television networks reaching them along with government sponsored national and privately owned local ones. Our comparative analyses of teens talking about their everyday lives and television reveal similarities and differences in their lived realities and in their relationships to and interpretations of television programs and characters. The findings show patterns clustered around the teens' gender, class, and teen identities, but these are complicated by their experiences of family, peers, school, religion, language, and nation, as well as different regional television offerings. Television played a role in their ongoing journeys toward selfhood; these journeys are thoroughly groun...

Author(s): McMillin, Stella; Piazza, Melanie S.; Woods, Leslie W.; Poppenga, Robert H. | Abstract: Bromethalin is being used more widely for commensal rodent control because of increased regulation on second-generation anticoagulant rodenticides. Wildlife losses in California are tracked by the California Department of Fish and Wildlife. Bromethalin is a neurotoxicant which is not thought to cause secondary poisoning. From August 2014 to January 2016, 24 cases of bromethalin intoxication were investigated in California. These include 11 raccoons, 11 striped skunks, one gray fox, and one fox squirrel. Most of these occurred in Marin County, where active surveillance of wildlife for rodenticide exposure is occurring. Bromethalin exposure should be evaluated when a wild animal that may have accessed bait is showing neurological signs. Trauma and distemper should be ruled out. Histological changes may be found in the central nervous system but are not always present. The tissue of choice for toxicological analysis is adipose. It is likely that bromethalin intoxication is under-reported in the rest of the state and may be mistaken for distemper infection or trauma. Primary exposure of wildlife to bromethalin could be prevented by placing baits in tamper-resistant bait stations.

Situated within a critical, feminist approach to development communication, this study examines the role of television advertising among unskilled female factory laborers in Bangalore, India. Ethnographic fieldwork spanning the summers of 1997 and 2000 showed that factory labor awards the female worker a degree of autonomy and purchasing power in the short term, but denies her long-term empowerment because her labor is fragmented and made dispensable by the very nature of capitalist discipline. Through a discussion of gender, labor, and television in the global city, the analysis concludes that participatory communication and further ethnographic analyses are essential for long-lasting policy and social action.

Content analyses of Indian television programmes on the national network Doordarshan in the 1980s have shown that prime-time shows cast women as docile homemakers and as objects of male desire. This paper uses a critical postcolonial theoretical framework and narrative analysis method to detect ideologies of gender from programmes randomly selected from a month's menu of the transnational, national and regional television networks in the country. A broad conclusion is that Indian television in the late 1990s perpetuates, across channels, the 1980s' stereotypical images of women, images that have their roots in Vedic, colonial, and nationalist literature. The status quo is explained through a critical discussion of the framing of 'woman' in colonial and postcolonial nation-building efforts. The paper also points to the emerging genre of hybrid programming, where the greater incidence of female veejays and talk show hosts paves the way for the expression of female leadership and desire, and leads to more positive television portrayals of women in the 21st century.

In this article I examine the cultural role of private and state-controlled television networks in India and their negotiation of identities through profitable hybrid programming. I draw attention to a new emerging power in processes of globalization: indigenous, regional television networks. Ethnography in Bangalore, India, in 1997 and 2000 revealed that regional, private, vernacular language networks indeed played a crucial role in local imaginings and, in the long run, may rise in tremendous political power through their manipulation and reflection of regional identity. The analysis leads to a critique of local media markets and the location of ‘nation’ in global media processes.

Author(s): McMillin, Stella C. | Abstract: The California Department of Fish and Game (DFG) recognizes the need for the availability of a variety of tools for vertebrate pest control and has a strong interest in ensuring that these tools are used in a way that minimizes impacts to nontarget wildlife. From 1992 to 2011, the DFG has investigated 44 cases of wildlife kills caused by vertebrate pesticides, resulting in the loss of 258 animals. While anticoagulant rodenticides were responsible for the loss of the highest number of incidents, incidents involving acute toxicants, such as strychnine and zinc phosphide, typically involved a greater number of animals per incident. Incidents of intentional poisoning of wildlife usually involved strychnine. There were no documented losses due to fumigants; however, such incidents are likely to go unnoticed because the carcasses remain underground.

Artificial disc replacement was performed in six patients with an average age of 55 years and average follow-up of 3.4 years. Four of the six patients had juxtafusion degeneration, one had multilevel disc degeneration, and one patient had isolated disc resorption. The Acroflex disc (Acromed Corporation, Cleveland, OH), which was used in the replacement, is composed of a rubber core vulcanized to two titanium end plates. The latter have superior posts to provide for initial mechanical fixation and porous in-growth surfaces for long-term fixation. Satisfactory results occurred in four of six patients. Poor results occurred in the presence of deformity that resulted in prosthetic failure and isolated disc resorption. There was an average 8 degrees angular and 2.3-mm translational movement and satisfactory in-growth at all interfaces. Design objectives of endurance, biocompatibility, geometry, kinematics, constraint, dynamics, stability, and fail-safe were met; however, this study is preliminary in nature.

Author(s): McMillin, Stella C.; Finlayson, Brian F. | Abstract: In 2008, approximately 70 Canada geese were recovered dead in the Moro Cojo Slough area of Monterey County, California. Birds were necropsied and showed signs of abnormal internal bleeding. A total of 37 livers were analyzed for anticoagulants and 36 of these livers contained chlorophacinone. Death was attributable to chlorophacinone poisoning. Two turkey vultures and a barn owl also died, probably as a result of secondary chlorophacinone poisoning. The source of the chlorophacinone was not obvious, as chlorophacinone is used in several different forms on many different crops and also in commensal use. In addition, there often are several days between exposure and death, allowing the movement of the animal from the site of exposure. The ensuing investigations, which lasted several months, suggested that the exposure was due to expanded use of chlorophacinone pellets on artichokes used to control California voles. Subsequently, the label of the rodenticide product was modified to restrict its use when conditions favor goose presence in artichoke fields. No deaths have occurred since the label modification.

Author(s): McMillin, Stella C.; Hosea, Robert C.; Finlayson, Brian F.; Cypher, Brian L.; Mekebri, Abdou | Abstract: Concerned that San Joaquin kit foxes from urban areas may be exposed to commensal anticoagulants, the California Department of Fish and Game, Pesticide Investigations Unit, in conjunction with the Endangered Species Recovery Program’s Urban Kit Fox Project, began monitoring San Joaquin kit foxes from the Bakersfield, CA population. Necropsies were performed and liver tissue samples collected from kit fox carcasses. Livers from archived kit foxes dating back to 1977 were also analyzed. A non-urban population of San Joaquin kit foxes from Lokern was used as a control. Other predators in the area, including coyotes and red foxes, were also analyzed for comparison. Between 1999 and 2007, tissue samples from 45 animals have been analyzed for residues of anticoagulant rodenticides. Anticoagulant compounds identified included brodifacoum, bromadiolone, pival, and chlorophacinone. Twenty-six of the 30 San Joaquin kit foxes from Bakersfield contained at least one anticoagulant, and the most commonly detected anticoagulant was brodifacoum. None of the 12 Lokern San Joaquin kit foxes contained anticoagulants. Other predators followed the same pattern: both red foxes from Bakersfield contained anticoagulant residues, but the coyote taken from Lokern did not.

B-Raf is an important mediator of cell proliferation and survival signals transduced via the Ras-Raf-MEK-ERK cascade. BRAF mutations have been detected in several tumors, including papillary thyroid carcinoma, but the precise role of B-Raf as a therapeutic target for thyroid carcinoma is still under investigation. We analyzed a panel of 93 specimens and 14 thyroid carcinoma cell lines for the presence of BRAF mutations and activation of the mitogen-activated protein/ERK kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway. We also compared the effect of a B-Raf small inhibitory RNA construct and the B-Raf kinase inhibitor AAL881 on both B-Raf wild-type and mutant thyroid carcinoma cell lines. We found a high prevalence of the T1799A (V600E) mutation in papillary and anaplastic carcinoma specimens and cell lines. There was no difference in patient age, B-Raf expression, Ki67 immunostaining, or clinical stage at presentation between wild-type and BRAFV600E specimens. Immunodetection of phosphorylated and total forms of MEK and ERK revealed no difference in their phosphorylation between wild-type and BRAFV600E patient specimens or cell lines. Furthermore, a small inhibitory RNA construct targeting the expression of both wild-type B-Raf and B-RafV600E induced a comparable reduction of viability in both wild-type and BRAFV600E mutant cancer cells. Interestingly, AAL881 inhibited MEK and ERK phosphorylation and induced apoptosis preferentially in BRAFV600E-harboring cells than wild-type ones, possibly because of better inhibitory activity against B-RafV600E. We conclude that B-Raf is important for the pathophysiology of thyroid carcinomas irrespective of mutational status. Small molecule inhibitors that selectively target B-RafV600E may provide clinical benefit for patients with thyroid cancer. Copyright © 2007 American Association for Cancer Research.

Artificial disc replacement was performed in six patients with an average age of 55 years and average follow-up of 3.4 years. Four of the six patients had juxtafusion degeneration, one had multilevel disc degeneration, and one patient had isolated disc resorption. The Acroflex disc (Acromed Corporation, Cleveland, OH), which was used in the replacement, is composed of a rubber core vulcanized to two titanium end plates. The latter have superior posts to provide for initial mechanical fixation and porous in-growth surfaces for long-term fixation. Satisfactory results occurred in four of six patients. Poor results occurred in the presence of deformity that resulted in prosthetic failure and isolated disc resorption. There was an average 8 degrees angular and 2.3-mm translational movement and satisfactory in-growth at all interfaces. Design objectives of endurance, biocompatibility, geometry, kinematics, constraint, dynamics, stability, and fail-safe were met; however, this study is preliminary in nature.

Ten chlorinated hydrocarbons (tetradifon, Chlorobenzilate, Kepone, lindane, Kelthane, toxaphene, dieldrin, hexachlorobenzene, dienochlor, and Aroclor 1254; see below) were evaluated in rats to assess agents which might selectively elevate high-density lipoprotein cholesterol (C-HDL). Single, nontoxic doses of Aroclor, dieldrin, and Kepone elevated C-HDL at day 7 (31%, 26%, and 24%, respectively, p less than 0.05). The C-HDL elevations were maintained at days 21 and 60 (28% and 31%, p less than 0.01) in the Aroclor group, while C-HDL returned to baseline in the dieldrin and Kepone groups. Liver function tests were unchanged from control, suggesting that the changes in C-HDL were not the consequence of hepatotoxicity. The hepatic microsomal cytochrome P-450 content of animals receiving Aroclor, dieldrin, and Kepone was 67%, 56%, and 44% higher than control values (p less than 0.02), indicating probable hepatic enzyme induction. If HDL (an antiatherogenic lipoprotein) is also selectively elevated by chlorinated hydrocarbons in man, then analogues might potentially be developed as antiatherogenic pharmacologic agents. Alternatively, the implications of man's exposure to halogenated hydrocarbons may be better understood.

Stocks of cloned helper-independent Rous sarcoma virus (RSV) spontaneously segregate transformation-defective ( td ) mutants that appear to have an RNA genome composed of smaller subunits than those of the patent virus. Differential hybridization and competitive hybridization techniques involving reactions between viral RNA and proviral sequences in host cell DNA (under conditions of initial DNA excess) were used to measure the extent of the deletion in a td mutant of Prague strain (Pr) of RSV (Pr RSV-C). Viral 60 to 70 S RNA sequences labeled to 1 to 5 × 10 7 counts per min per μg with 125 I were characterized with respect to their properties in hybridization reactions and used to reinforce data obtained with [ 3 H]RNA of lower specific activity. By these techniques, about 13% ± 3% of the sequences Pr RSV-C that formed hybrids with DNA from virus-induced sarcomas appeared to be deleted from the genome of td Pr RSV-C. Studies comparing hybridization of RNA from Pr RSV-C and td Pr RSV-C with RSV-related sequences in normal cells, and competition experiments with RNA from the endogenous chicken oncornavirus Rous-associated virus type 0 (RAV-0) provided evidence that the majority, if not all, of the RNA sequences of Pr RSV-C deleted from its transformation-defective mutant are not represented in normal chicken DNA. Competition studies with a leukosis virus, RAV-7, indicated this virus also lacks a genome segment of about the same size as the deletion in the td mutant. Finally, the genome of all three “exogenous” viruses was found to lack a small segment (about 12%) of sequences present in the endogenous provirus of RAV-O.

1. The present paper is a study of the growth of a clam ( Siliqua patula ) under natural conditions and over a wide range of latitude. 2. Various constants derived from the growth data are compared for the different localities. For this species, over the range considered, growth in the southern localities as compared with the northern is initially more rapid but less sustained, leads to a smaller total length and is associated with a shorter life span. 3. Reasons are presented for considering the relative growth-rate as a particularly significant constant leading to more sound biological conclusions than the use of the absolute growth-rate. 4. On the basis of the relative growth-rate, current mathematical expressions for the course of growth are discussed and a formula used which emphasises Minot's conception of a growth-rate constantly declining with age. This expression L = Be - ce - ce - kt , in which L = length at time t , e = base of natural logarithms, and B , c and k are constants, is found to graduate the extensive data in clam growth with significant accuracy. Published with the permission of the United States Commissioner of Fisheries.

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In discussing the growth of the razor clam (Siliqua patula, Dixon) we have pointed out a correlation between the absolute growth rate and the variability as measured by “D”, the interdecile range.1 In this work we used samples of clams representing the normal population of the respective beds. For this reason the numbers in the older age groups were small, and it was not possible to determine the presence or extent of selective mortality which might greatly affect the relation between growth and variance.Recently we have selected 2 samples of clams, one from Little River, Humboldt County, California, containing 300 specimens, all 7 years of age, and one from Hallo Bay on the Alaskan Peninsula, containing 76 specimens 13 years old. A complete growth record was obtained for each individual by measuring the consecutive annual rings. The mean length and the variance were calculated for each year for the 2 localities, and the tenth, the fiftieth (median), and the ninetieth percentiles were determined for the d...

The purpose of the study was to characterize flow properties within a clinical pusher plate type artificial heart. Dual camera video tape and synchronized still photographs were used to study flow patterns. Diffused light and a planar laser source provided illumination. The laser light was turned into a plane of light with a thickness varying from 0.1 to 10 mm, and magnesium oxide and Amberlite particles were used as tracers. Qualitative and quantitative analyses were performed by the examination and digitization of flow patterns. Inflow, outflow, pneumatic drive and after-load pressure, diaphragm motion, cardiac output, and heart rate were measured and recorded. An electrical circuit was developed to synchronize pump diaphragm motion with captured images of flow trajectories. Trajectories were then digitized, and velocities, turbulence, and shear stresses were calculated. As the result of these experiments, disturbed, recirculating, and stagnation zones were identified and global and local turbulence values were determined. Simultaneous turbulence, stasis, recirculation, and laminar flow patterns were observed during most phases of the pumping cycle. Velocities obtained varied from 2 cm/sec to 145 cm/sec; total local shear stresses of 12 to 897 dynes/cm2 were seen.