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1.
Curr Biol ; 18(9): 699-703, 2008 May 06.
Article in English | MEDLINE | ID: mdl-18450445

ABSTRACT

Although there are numerous examples of animals having photoreceptors sensitive to UVA (315-400 nm) [1] and relying on UVA-based mate-choice cues [2-5], here we provide the first evidence of an animal using UVB (280-315 nm) for intraspecific communication. An earlier study showed that Phintella vittata, a jumping spider (Salticidae) from China, reflects UVB [6]. By performing six series of binary mate-choice experiments in which we varied lighting conditions with filters (UVB+ [no filter] versus UVB-, UVB+ versus ND1, UVB+ versus ND2, UVB- versus ND1, UVB- versus ND2, and UVB- versus UVA-), we show that significantly more UVB + males than UVB- males are chosen by females as preferred mates. Female preference for UVB-reflective males is not affected by differences in brightness or by UVA.


Subject(s)
Animal Communication , Mating Preference, Animal/physiology , Spiders/physiology , Ultraviolet Rays , Visual Perception/physiology , Animals , Cues , Female , Male
2.
J Anim Ecol ; 79(5): 937-47, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20487086

ABSTRACT

1. We review the mechanisms behind ecosystem functions, the processes that facilitate energy transfer along food webs, and the major processes that allow the cycling of carbon, oxygen and nitrogen, and use case studies to show how these have already been, and will continue to be, altered by global warming. 2. Increased temperatures will affect the interactions between heterotrophs and autotrophs (e.g. pollination and seed dispersal), and between heterotrophs (e.g. predators-prey, parasites/pathogens-hosts), with generally negative ramifications for important ecosystem services (functions that provide direct benefit to human society such as pollination) and potential for heightened species co-extinction rates. 3. Mitigation of likely impacts of warming will require, in particular, the maintenance of species diversity as insurance for the provision of basic ecosystem services. Key to this will be long-term monitoring and focused research that seek to maintain ecosystem resilience in the face of global warming. 4. We provide guidelines for pursuing research that quantifies the nexus between ecosystem function and global warming. These include documentation of key functional species groups within systems, and understanding the principal outcomes arising from direct and indirect effects of a rapidly warming environment. Localized and targeted research and monitoring, complemented with laboratory work, will determine outcomes for resilience and guide adaptive conservation responses and long-term planning.


Subject(s)
Ecosystem , Global Warming , Animals , Energy Transfer
3.
Proc Biol Sci ; 274(1609): 569-75, 2007 Feb 22.
Article in English | MEDLINE | ID: mdl-17476778

ABSTRACT

Recent studies have shown for birds that females sometimes choose mates on the basis of condition-dependent variation in ultraviolet (UV, less than 400 nm) ornamentation, but there have been few comparable studies on invertebrates. Yet many invertebrates have UV structural coloration. Here, we investigate Cosmophasis umbratica, a jumping spider (Araneae: Salticidae) that has sexually dimorphic UV-iridescent ornamentation, and we provide evidence that male UV coloration is condition dependent in this species. Spectral-reflection patterns change with male age and prior feeding history. The position of the UV band (i.e. UV hue) of the carapaces of younger (field-collected as subadults and matured as adults in laboratory) males shifted, relative to older (field-collected as adults) males, significantly towards longer wavelengths. Food deprivation significantly decreased the spectral intensity of the abdomen, but not the carapace. Questions concerning the mechanisms by which UV ornaments change are highlighted, as are hypotheses concerning the role of condition-dependent UV variation in male-male competition and as a criterion used by females when making mate-choice decisions.


Subject(s)
Animal Communication , Spiders/anatomy & histology , Ultraviolet Rays , Age Factors , Animals , Feeding Behavior , Female , Male , Mating Preference, Animal , Sex Characteristics , Spiders/physiology
4.
Proc Biol Sci ; 274(1618): 1583-9, 2007 Jul 07.
Article in English | MEDLINE | ID: mdl-17456453

ABSTRACT

The jumping spider Cosmophasis umbratica from Singapore is strongly sexually dimorphic. The males, but not the females, reflect ultraviolet as well as green-orange light. The scales responsible for this are composed of a chitin-air-chitin sandwich in which the chitin layers are three-quarters of a wavelength thick and the air gap a quarter wavelength (where lambda=600 nm, the peak wavelength of the principal reflection maximum). It is shown that this configuration produces a second reflectance peak at approximately 385 nm, accounting for the observed reflection in the ultraviolet. Other scales have a similar thickness of chitin but lack the air gap and thus produce a dull purple reflection. This novel mechanism provides the spiders with two colour signals, both of which are important in mating displays.


Subject(s)
Chitin/chemistry , Color , Spiders/anatomy & histology , Ultraviolet Rays , Animals , Chitin/radiation effects , Male , Microscopy, Electron, Transmission , Microscopy, Interference , Models, Theoretical
5.
Mil Med ; 170(4 Suppl): 30-8, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15916281

ABSTRACT

Diarrhea, a scourge upon humanity since preliterate times, has been the particular nemesis of military forces. The Armed Forces of the United States have been in the forefront in the diagnosis, treatment, and prevention of diarrheal illness. U.S. military scientists and physicians implemented the first mandatory typhoid inoculation program, contributed to advances in water chlorination, and pioneered the use of antibiotics for typhoid fever. U.S. Navy physicians refined the intravenous treatment of cholera, reducing the death rate from 20% to less than 1%. Their studies of electrolyte and fluid balance in cholera, and the subsequent development of oral rehydration therapy for cholera and other diarrheal illness, have saved millions of lives worldwide. U.S. Army researchers refuted the desquamation theory of cholera pathogenesis, isolated the cholera exotoxin, and developed improved cholera vaccines. U.S. Army and Navy researchers pioneered the use of antibiotics for the treatment of typhoid fever, made major contributions to the treatment of dysentery, developed algorithms for the treatment of traveler's diarrhea, and continue active development of traveler's diarrhea and dysentery vaccines. U.S. military diarrheal research has directly contributed to the welfare of hundreds of millions of people.


Subject(s)
Diarrhea/history , Military Medicine/history , Biomedical Research/history , History, 18th Century , History, 19th Century , History, 20th Century , Humans , United States
6.
Infect Dis Clin North Am ; 18(2): 261-74, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15145380

ABSTRACT

Throughout history, infectious diarrhea has been associated with crowding, poor sanitation, and war. Although descriptions of infectious diarrhea exist in the earliest records of civilization, effective measures for prevention were not widely or consistently used until the modern era of active public health promotion. Advances in the understanding of etiologies and therapies have revolutionized prognosis; however, constant vigilance against lapses in public health is necessary to prevent outbreaks of disease.


Subject(s)
Dysentery/history , Cholera/history , Dysentery/etiology , Dysentery/therapy , History, 18th Century , History, 19th Century , History, 20th Century , History, Ancient , History, Medieval , Humans , Typhoid Fever/history
7.
Arch Dermatol ; 139(5): 629-34, 2003 May.
Article in English | MEDLINE | ID: mdl-12756100

ABSTRACT

BACKGROUND: Rapidly growing mycobacteria (RGM) can cause a variety of cutaneous and systemic diseases. The causative organisms are typically Mycobacterium fortuitum or Mycobacterium chelonae (also known as Mycobacterium abscessus). Primary cutaneous lesions may develop after a variable latent period, from weeks to several months, and usually result from direct inoculation after trauma, from injections, or during surgery via contaminated medical instruments. Recently, investigators from the Centers for Disease Control and Prevention, Atlanta, Ga, and the California Department of Health Services, Berkeley, documented a large, unprecedented outbreak of community-acquired RGM infection, during which more than 100 patrons of a northern California nail salon contracted furunculosis in their legs as a result of exposure to whirlpool footbaths that were contaminated with M fortuitum. OBSERVATIONS: We report the clinical and epidemiological findings in 3 cases of lower extremity RGM infections that occurred after similar whirlpool footbath exposure at several different nail salons in southern California. These infections typically presented as recurrent furunculosis, causing considerable morbidity as a result of scarring, delayed diagnosis, and the need for long-term polymicrobial therapy. CONCLUSIONS: Rapidly growing mycobacterial infections related to pedicures may continue to occur in a sporadic fashion. Clinicians should consider the possibility of RGM infection and inquire about recent pedicures in a patient with recurrent lower extremity furunculosis and abscesses that are unresponsive to conventional antibiotic therapy.


Subject(s)
Furunculosis/etiology , Hydrotherapy/adverse effects , Mycobacterium Infections, Nontuberculous/etiology , Mycobacterium chelonae/growth & development , Mycobacterium fortuitum/growth & development , Adult , Child , Female , Furunculosis/microbiology , Furunculosis/pathology , Humans , Mycobacterium Infections, Nontuberculous/microbiology , Mycobacterium Infections, Nontuberculous/pathology , Mycobacterium chelonae/isolation & purification , Mycobacterium fortuitum/isolation & purification , Time Factors
8.
Mil Med ; 169(5): 373-5, 2004 May.
Article in English | MEDLINE | ID: mdl-15186002

ABSTRACT

We describe a case series of group A Streptococcus (GAS) necrotizing fasciitis occurring over a 10-week period in military recruits undergoing intense physical training. These cases highlight that GAS may cause life-threatening infections in addition to mild diseases such as pharyngitis. This series suggests that the incidence of severe GAS infections may be increasing in certain populations and it emphasizes the importance of considering prophylactic measures against GAS in high-risk populations.


Subject(s)
Fasciitis, Necrotizing/epidemiology , Military Personnel/statistics & numerical data , Streptococcal Infections/epidemiology , Streptococcus pyogenes/isolation & purification , Adult , California/epidemiology , Fasciitis, Necrotizing/diagnosis , Fasciitis, Necrotizing/microbiology , Humans , Incidence , Male , Risk Factors , Streptococcal Infections/complications , Streptococcal Infections/diagnosis , Teaching
9.
Mil Med ; 168(6): 460-4, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12834136

ABSTRACT

We recently evaluated a cluster of cases of disseminated coccidioidomycosis referred to the Naval Medical Center San Diego. Between March and June of 2002, seven cases were diagnosed and treated. In a 5-year record review (March 1997-February 2002), we found only seven cases of disseminated disease attributable to Coccidioides immitis at the same institution. This report of seven cases over a 3-month period represents a 20-fold increase in the number of complicated C. immitis infections. All cases were non-Caucasians, had disseminated disease to bone and/or skin without meningeal involvement, and had a delay of 1.5 to 6 months from symptom onset until the diagnosis of coccidioidomycosis. Four of our cases occurred in previously healthy, young active duty members, emphasizing the importance of this mycosis in U.S. military personnel.


Subject(s)
Coccidioidomycosis/epidemiology , Adolescent , Adult , California/epidemiology , Coccidioides , Female , Hospitals, Military , Humans , Incidence , Male , Middle Aged , Military Personnel
10.
Chest ; 146(4 Suppl): e87S-e102S, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25144713

ABSTRACT

BACKGROUND: System-level planning involves uniting hospitals and health systems, local/regional government agencies, emergency medical services, and other health-care entities involved in coordinating and enabling care in a major disaster. We reviewed the literature and sought expert opinions concerning system-level planning and engagement for mass critical care due to disasters or pandemics and offer suggestions for system-planning, coordination, communication, and response. The suggestions in this chapter are important for all of those involved in a pandemic or disaster with multiple critically ill or injured patients, including front-line clinicians, hospital administrators, and public health or government officials. METHODS: The American College of Chest Physicians (CHEST) consensus statement development process was followed in developing suggestions. Task Force members met in person to develop nine key questions believed to be most relevant for system-planning, coordination, and communication. A systematic literature review was then performed for relevant articles and documents, reports, and other publications reported since 1993. No studies of sufficient quality were identified upon which to make evidence-based recommendations. Therefore, the panel developed expert opinion-based suggestions using a modified Delphi process. RESULTS: Suggestions were developed and grouped according to the following thematic elements: (1) national government support of health-care coalitions/regional health authorities (HC/RHAs), (2) teamwork within HC/RHAs, (3) system-level communication, (4) system-level surge capacity and capability, (5) pediatric patients and special populations, (6) HC/RHAs and networks, (7) models of advanced regional care systems, and (8) the use of simulation for preparedness and planning. CONCLUSIONS: System-level planning is essential to provide care for large numbers of critically ill patients because of disaster or pandemic. It also entails a departure from the routine, independent system and involves all levels from health-care institutions to regional health authorities. National government support is critical, as are robust communication systems and advanced planning supported by realistic exercises.


Subject(s)
Consensus , Critical Illness/therapy , Disasters , Emergency Medical Services/organization & administration , Health Planning Organizations/organization & administration , Pandemics , Wounds and Injuries/therapy , Critical Care/organization & administration , Humans
11.
Chest ; 146(4 Suppl): e156S-67S, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25144337

ABSTRACT

BACKGROUND: Planning for mass critical care (MCC) in resource-poor or constrained settings has been largely ignored, despite their large populations that are prone to suffer disproportionately from natural disasters. Addressing MCC in these settings has the potential to help vast numbers of people and also to inform planning for better-resourced areas. METHODS: The Resource-Poor Settings panel developed five key question domains; defining the term resource poor and using the traditional phases of disaster (mitigation/preparedness/response/recovery), literature searches were conducted to identify evidence on which to answer the key questions in these areas. Given a lack of data upon which to develop evidence-based recommendations, expert-opinion suggestions were developed, and consensus was achieved using a modified Delphi process. RESULTS: The five key questions were then separated as follows: definition, infrastructure and capacity building, resources, response, and reconstitution/recovery of host nation critical care capabilities and research. Addressing these questions led the panel to offer 33 suggestions. Because of the large number of suggestions, the results have been separated into two sections: part 1, Infrastructure/Capacity in this article, and part 2, Response/Recovery/Research in the accompanying article. CONCLUSIONS: Lack of, or presence of, rudimentary ICU resources and limited capacity to enhance services further challenge resource-poor and constrained settings. Hence, capacity building entails preventative strategies and strengthening of primary health services. Assistance from other countries and organizations is needed to mount a surge response. Moreover, planning should include when to disengage and how the host nation can provide capacity beyond the mass casualty care event.


Subject(s)
Capacity Building/organization & administration , Consensus , Critical Care/organization & administration , Critical Illness/therapy , Health Resources/organization & administration , Pandemics , Wounds and Injuries/therapy , Humans
12.
Chest ; 146(4 Suppl): e168S-77S, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25144410

ABSTRACT

BACKGROUND: Planning for mass critical care in resource-poor and constrained settings has been largely ignored, despite large, densely crowded populations who are prone to suffer disproportionately from natural disasters. As a result, disaster response has been suboptimal and in many instances hampered by lack of planning, education and training, information, and communication. METHODS: The Resource-Poor Settings panel developed five key question domains; defining the term resource poor and using the traditional phases of the disaster cycle (mitigation/preparedness/response/recovery). Literature searches were conducted to identify evidence to answer the key questions in these areas. Given a lack of data on which to develop evidence-based recommendations, expert-opinion suggestions were developed, and consensus was achieved using a modified Delphi process. RESULTS: The five key questions were as follows: definition, capacity building and mitigation, what resources can we bring to bear to assist/surge, response, and reconstitution and recovery of host nation critical care capabilities. Addressing these led the panel to offer 33 suggestions. Because of the large number of suggestions, the results have been separated into two sections: part I, Infrastructure/Capacity in the accompanying article, and part II, Response/Recovery/Research in this article. CONCLUSIONS: A lack of rudimentary ICU resources and capacity to enhance services plagues resource-poor or constrained settings. Capacity building therefore entails preventative strategies and strengthening of primary health services. Assistance from other countries and organizations is often needed to mount a surge response. Moreover, the disengagement of these responding groups and host country recovery require active planning. Future improvements in all phases require active research activities.


Subject(s)
Consensus , Critical Illness/therapy , Disasters , Health Resources/organization & administration , Pandemics , Research/organization & administration , Wounds and Injuries/therapy , Critical Care/standards , Humans
13.
PLoS One ; 8(4): e59774, 2013.
Article in English | MEDLINE | ID: mdl-23573210

ABSTRACT

Animal colour signals used in intraspecies communications can generally be attributed to a composite effect of structural and pigmentary colours. Notably, the functional role of iridescent coloration that is 'purely' structural (i.e., absence of pigments) is poorly understood. Recent studies reveal that iridescent colorations can reliably indicate individual quality, but evidence of iridescence as a pure structural coloration indicative of male quality during contests and relating to an individual's resource-holding potential (RHP) is lacking. In age- and size-controlled pairwise male-male contests that escalate from visual displays of aggression to more costly physical fights, we demonstrate that the ultraviolet-green iridescence of Cosmophasis umbratica predicts individual persistence and relates to RHP. Contest initiating males exhibited significantly narrower carapace band separation (i.e., relative spectral positions of UV and green hues) than non-initiators. Asymmetries in carapace and abdomen brightness influenced overall contest duration and escalation. As losers retreated upon having reached their own persistence limits in contests that escalated to physical fights, losers with narrower carapace band separation were significantly more persistence. We propose that the carapace UV-green iridescence of C. umbratica predicts individual persistence and is indicative of a male's RHP. As the observed UV-green hues of C. umbratica are 'pure' optical products of a multilayer reflector system, we suggest that intrasexual variations in the optical properties of the scales' chitin-air-chitin microstructures are responsible for the observed differences in carapace band separations.


Subject(s)
Competitive Behavior , Pigmentation , Spiders/anatomy & histology , Animals , Male , Regression Analysis , Ultraviolet Rays
15.
Science ; 315(5811): 481, 2007 Jan 26.
Article in English | MEDLINE | ID: mdl-17255504

ABSTRACT

No animals are known to possess both ultraviolet (UV) reflectance and fluorescence that are sex-specific. We provide evidence for this separation in the jumping spider Cosmophasis umbratica, which has UV reflectance and UV-induced green fluorescence restricted to males and females, respectively. During courtship, many of the studied pairs failed to show typical display posturing when UV light was blocked. Occluding the UV component of sunlight to only one of each pair also caused atypical behavior: Females showed no interest in non-UV-reflective courting males, and males either ignored or were lackluster in courting nonfluorescing females. These results demonstrate the importance of both sex-specific hues as sexual signals for effective intraspecific communication.


Subject(s)
Fluorescence , Photoreceptor Cells, Invertebrate/physiology , Sexual Behavior, Animal , Spiders/physiology , Ultraviolet Rays , Animals , Cues , Female , Male , Sex Characteristics , Spectrometry, Fluorescence
16.
Article in English | MEDLINE | ID: mdl-16598507

ABSTRACT

Jumping spiders are known to possess ultraviolet (UV) receptors in the retinas of their large-principal eyes. The existence of UV visual cells, however, does not prove that jumping spiders can see into the UV part of spectrum (300-400 nm) or whether such an ability plays any role in salticid intra-specific interactions. In the study reported herein, we performed behavioural experiments to test whether a UV-reflecting jumping spider, Cosmophasis umbratica, is sensitive to UV wavelengths and whether UV cues are important in intra-specific communication. The absence of UV cues not only affected intra-specific behaviour by significantly reducing the frequency of agonistic displays, but also elicited unprecedented courtship displays in males towards their own mirror images and conspecific opponents. Furthermore, C. umbratica males were able to respond rapidly to changes in UV cues of conspecific mirror images by switching between agonistic and courtship displays. These findings clearly demonstrate that C. umbratica males are capable of seeing UV wavelengths and that UV cues are necessary and sufficient for this species to enable the agonistic displays. Hence, UV light may have an important role to play in intra-specific communication in jumping spiders.


Subject(s)
Animal Communication , Behavior, Animal/radiation effects , Spiders/physiology , Ultraviolet Rays , Animals , Cues , Female , Male , Predatory Behavior/radiation effects , Sex Factors , Sexual Behavior, Animal/radiation effects
17.
Science ; 319(5861): 281, 2008 Jan 18.
Article in English | MEDLINE | ID: mdl-18202272
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