Minimalist style boot improves running but not walking economy in trained men.

This study examined movement economy under load with 1000 g minimalist (MIN) vs. 1600 g traditional (TRD) style boots. Fourteen trained, male participants completed a VO2peak test (46.6 ± 7.3 ml/kg/min) while wearing a 16 kg external load. Treadmill speeds for the running economy (RE) trials were determined by the slowest pace in which participants completed a full stage with a running gait pattern during the VO2peak test. Walking economy (WE) pace was 1.6 km/h slower than RE pace. During the second session, participants completed 5-min exercise bouts at WE and RE pace under load wearing MIN and TRD. There were no differences for any measured variables during WE trials. In contrast, RE (MIN = 2.95 ± 0.28 vs. TRD = 3.04 ± 0.30 L/min; p = .003: Cohen's d = 0.32), respiratory exchange ratio (p < .001), and perceptual measures (p < .05) were all improved while wearing MIN. Practitioner summary: In trained men, 1000 g/pair minimalist style boots (MIN) resulted in improvements of approximately 3% and 5% for running economy and respiratory exchange ratio versus 1600 g/pair traditional boots while wearing a 16 kg kit. Perceptual responses, including comfort, also favoured MIN. These effects were not found at walking pace. Abbreviations: MIN: minimalist style boots; TRD: traditional style boots; RE: running economy; WE: walking economy; ES: effect size; RER: respiratory exchange ratio; HR: heart rate.

Intraspecific Root Grafts and Clonal Growth Within Ailanthus altissima Stands Influence Verticillium nonalfalfae Transmission.

Verticillium nonalfalfae, causal agent of Verticillium wilt, is being considered as a biocontrol for the highly invasive Ailanthus altissima in Pennsylvania. This soilborne fungus is extremely virulent on Ailanthus and rapidly transmitted from diseased to healthy trees within Ailanthus stands. The rapid transmission of the fungus could be facilitated by root grafts, but neither root graft formation in Ailanthus nor Verticillium transmission by root grafts in trees has been reported. Here, V. nonalfalfae transmission between diseased and healthy Ailanthus trees via intraspecific root grafts and clonal growth is evaluated. Using air-spade excavation, dye translocation, and root graft inoculations, functional root grafts were detected between Ailanthus trees and transmission of V. nonalfalfae across root grafts demonstrated. Inoculation of one Ailanthus parent stem resulted in 187 root sprouts showing Verticillium wilt symptoms 12 months after inoculation. This study revealed that clonal growth and root grafts, normally advantageous growth habits, leave Ailanthus stands vulnerable to widespread V. nonalfalfae infection. This study also broadens the understanding of the Ailanthus-Verticillium pathosystem, growth strategies of invasive Ailanthus, and epidemiology of Verticillium wilt within trees.

Expanded Host Range Testing for Verticillium nonalfalfae: Potential Biocontrol Agent Against the Invasive Ailanthus altissima.

The naturally occurring Verticillium nonalfalfae has been proposed as a biocontrol agent against the highly invasive Ailanthus altissima in the eastern United States. We tested 71 nontarget woody species for susceptibility to the potential biocontrol agent. In the field, only devil's walkingstick (17% incidence) and striped maple (3%) acquired infections through natural spread from infected A. altissima (100%). Staghorn sumac (16% incidence) also exhibited wilt in close proximity to diseased Ailanthus, although V. nonalfalfae was never recovered. Stem inoculations, which are highly artificial in that they bypass root defenses and flood the xylem with millions of conidia, induced varying levels of wilt and mortality in 10 nontarget species from which V. nonalfalfae was reisolated, although recovery and crown rebuilding occurred following initial wilt in several species including sassafras and northern catalpa. Thirty-seven of the 71 inoculated species exhibited vascular discoloration, although 23 of these species exhibited no outward symptoms (wilt, dieback) for up to 6 years postinoculation. However, V. nonalfalfae was reisolated from three of the 23 species, indicating a tolerant host response. Our results suggest that V. nonalfalfae is generally host-adapted to A. altissima with 78 of 78 A. altissima seed sources from 26 states and Canada showing susceptibility, and offers support for adoption and dissemination of V. nonalfalfae to combat the highly invasive A. altissima.

Comparative pathogenicity, biocontrol efficacy, and multilocus sequence typing of Verticillium nonalfalfae from the invasive Ailanthus altissima and other hosts.

Verticillium wilt, caused by Verticillium nonalfalfae, is currently killing tens of thousands of highly invasive Ailanthus altissima trees within the forests in Pennsylvania, Ohio, and Virginia and is being considered as a biological control agent of Ailanthus. However, little is known about the pathogenicity and virulence of V. nonalfalfae isolates from other hosts on Ailanthus, or the genetic diversity among V. nonalfalfae from confirmed Ailanthus wilt epicenters and from locations and hosts not associated with Ailanthus wilt. Here, we compared the pathogenicity and virulence of several V. nonalfalfae and V. alfalfae isolates, evaluated the efficacy of the virulent V. nonalfalfae isolate VnAa140 as a biocontrol agent of Ailanthus in Pennsylvania, and performed multilocus sequence typing of V. nonalfalfae and V. alfalfae. Inoculations of seven V. nonalfalfae and V. alfalfae isolates from six plant hosts on healthy Ailanthus seedlings revealed that V. nonalfalfae isolates from hosts other than Ailanthus were not pathogenic on Ailanthus. In the field, 100 canopy Ailanthus trees were inoculated across 12 stands with VnAa140 from 2006 to 2009. By 2011, natural spread of the fungus had resulted in the mortality of >14,000 additional canopy Ailanthus trees, 10,000 to 15,000 Ailanthus sprouts, and nearly complete eradication of Ailanthus from several smaller inoculated stands, with the exception of a few scattered vegetative sprouts that persisted in the understory for several years before succumbing. All V. nonalfalfae isolates associated with the lethal wilt of Ailanthus, along with 18 additional isolates from 10 hosts, shared the same multilocus sequence type (MLST), MLST 1, whereas three V. nonalfalfae isolates from kiwifruit shared a second sequence type, MLST 2. All V. alfalfae isolates included in the study shared the same MLST and included the first example of V. alfalfae infecting a non-lucerne host. Our results indicate that V. nonalfalfae is host adapted and highly efficacious against Ailanthus and, thus, is a strong candidate for use as a biocontrol agent.

Effects of caffeine on session ratings of perceived exertion.

This study examined effects of caffeine on session ratings of perceived exertion (RPE) following 30 min constant-load cycling. Individuals (n = 15) of varying aerobic fitness completed a [Formula: see text] max trial and two 30 min cycling bouts (double-blind, counterbalanced) following ingestion of 6 mL/kg of caffeine or matched placebo. RPE overall, legs and breathing were estimated every 5 min and session RPE was estimated 30 min post-exercise using the OMNI pictorial scale. Session RPE for caffeine and placebo trails were compared using paired t test. Between-trial comparisons of HR, RPE overall, RPE legs and RPE breathing were analyzed using an independent 2 (trial) × 6 (time point) repeated measures analysis of variance (ANOVA) for each dependent variable. Caffeine resulted in a significantly lower session RPE (p < 0.05) for caffeine (6.1 ± 2.2) versus placebo (6.8 ± 2.1). Acute perceptual responses were significantly lower for caffeine for RPE overall (15, 20, 25, and 30 min), RPE breathing (15, 20, 25, and 30 min) and RPE legs (20 and 30 min). Survey responses post-exercise revealed greater feelings of nervousness, tremors, restlessness and stomach distress following caffeine versus placebo. Blunted acute RPE and survey responses suggest participants responded to caffeine ingestion. Caffeine decreased acute RPE during exercise which could partially account for lower session RPE responses. However, decreased session RPE could also reveal a latent analgesic affect of caffeine extending into recovery. Extending the understanding of session RPE could benefit coaches in avoiding overtraining when adjusting training programs.

First Report of Verticillium Wilt Caused by Verticillium nonalfalfae on Tree-of-Heaven (Ailanthus altissima) in Ohio.

Verticillium wilt of the highly invasive tree-of-heaven [Ailanthus altissima (Mill.) Swingle], caused by Verticillium nonalfalfae Interbitzin et al. (1), formerly classified as V. albo-atrum Reinke and Berthold, has been reported in the United States from two states: Pennsylvania (2) and Virginia (3). Infected A. altissima in both states exhibited similar symptoms of wilt, premature defoliation, terminal dieback, yellow vascular discoloration, and mortality. In June 2012, the second author observed dead and dying A. altissima trees in southern Ohio (Pike County) that exhibited symptoms similar to those on diseased A. altissima trees in Pennsylvania and Virginia. Samples were collected from stems of three symptomatic A. altissima trees and sent to Penn State for morphological and molecular identification. Immediately upon arrival, samples were surface-disinfected and plated onto plum extract agar (PEA), a semi-selective medium for Verticillium spp., amended with neomycin and streptomycin (2). The samples yielded six isolates, two from each of the three symptomatic trees, all of which were putatively identified as V. nonalfalfae based on the presence of verticillate conidiophores and formation of melanized hyphae. DNA was extracted from three isolates and molecular analyses performed using known primers (1) coding for elongation factor 1-alpha (EF), glyceraldehyde-3-phosphate dehydrogenase (GPD), and tryptophan synthase (TS). A BLAST search generated sequences that revealed 100% similarity to V. nonalfalfae for all three protein coding genes among the three Ohio isolates and reference sequences from Ailanthus, including isolates VnAaPA140 (GenBank Accession Nos. KC307764, KC307766, and KC307768) and VnAaVA2 (KC307758, KC307759, and KC307760), as well as isolate PD592 from potato (JN188227, JN188163, and JN188035), thereby confirming taxonomic placement of the Ohio Ailanthus isolates among those recovered from Ailanthus in Pennsylvania and Virginia. Aligned sequences from one representative isolate, VnAaOH1, were deposited into GenBank as accessions KC307761 (EF), KC307762 (GPD), and KC307763 (TS). In August 2012, the pathogenicity of all six isolates was confirmed by root-dipping 10 healthy 3-week-old A. altissima seedlings (seeds collected in University Park, PA) into conidial suspensions of 1 × 107 cfu/ml, wherein all inoculated seedlings wilted and died within 4 and 9 weeks, respectively. V. nonalfalfae was reisolated from all inoculated seedlings; control seedlings inoculated with distilled water remained asymptomatic. Ohio is the third state from which V. nonalfalfae has been reported to be pathogenic on A. altissima. If V. nonalfalfae proves to be widespread, it may represent a natural biocontrol for the invasive A. altissima. Also, since USDA APHIS evaluates and regulates new potential biocontrol agents on a state-by-state basis, it is important to document each state in which V. nonalfalfae is killing A. altissima, so that in-state inoculum can be used for biocontrol efforts, simplifying the regulatory process. References: (1) P. Inderbitzin et al. 2011 PLoS ONE, 6, e28341, 2011. (2) M. J. Schall and D. D. Davis. Plant Dis. 93:747, 2009. (3) A. L. Snyder et al. Plant Dis. 96:837, 2013.

Hydration profile and influence of beverage contents on fluid intake by women during outdoor recreational walking.

This study examined hydration status, sweat losses, and the effects of flavoring and electrolytes on fluid intake for women (n = 27, age = 24 ± 4 years) walking at a self-selected pace for ~1 h on a 1 km outdoor path during summer mornings or evenings. Over five consecutive days, participants consumed ad libitum one non-caloric beverage containing: (1) water (W), (2) acidified water (AW), (3) acidified water with electrolytes (AWE), (4) acidified water with flavor (AWF), and (5) acidified water with flavor and electrolytes (AWFE) in a counter-balanced order during walks and a 1-h recovery period. Walk Wet bulb globe temperature (26.2 ± 1.8 °C) and pace (6.0 ± 0.5 km/h) did not differ among beverages (P > 0.05). Thirty-four percent of pre-walk urine specific gravity samples exceeded 1.020. Flavoring (AWF 700 ± 393 mL; AWFE 719 ± 405 mL) did not result in greater consumption (P > 0.05) over W (560 ± 315 mL), with all three beverages exceeding grand mean sweat losses (528 ± 208 mL). Addition of electrolytes did not influence (P > 0.05) the intake between AW versus AWE or AWF versus AWFE. The results of this study indicate that the majority of women will consume fluids in excess of their sweat losses within 1 h post-walk. Over half of consumption took place during walks, highlighting the importance of fluid availability during exercise. Great among-subjects variability in sweat losses and fluid intake support the need for promoting individualized hydration strategies based on the changes in body mass for athletic populations.

Familial risk of pancreatic cancer.

BACKGROUND: Pancreatic cancer is the fifth leading cause of cancer-related mortality in the United STATES: Although smoking and age are known risk factors for pancreatic cancer, several case reports and case-control studies have suggested that there is also a familial risk. We evaluated whether a family history of pancreatic cancer increases the risk of pancreatic cancer in first-degree relatives and whether smoking and younger age at cancer diagnosis further increase this risk. METHODS: We conducted in-person interviews with 247 patients ("case probands") with pancreatic cancer and 420 population-based control probands to collect risk factor data and pancreatic cancer family history for 1816 first-degree relatives of the case probands and 3157 first-degree relatives of the control probands. We analyzed the data by unconditional logistic regression models, with adjustment for correlated data by use of generalized estimating equations. All statistical tests were two-sided. RESULTS: A positive family history of pancreatic cancer (i.e., being related to a case proband) or ever-smoking cigarettes approximately doubled the risk of pancreatic cancer (relative risk [RR] = 2.49; 95% confidence interval [CI] = 1.32 to 4.69; RR = 2.04; 95% CI = 1.09 to 3.83, respectively). The RR increased to 8.23 (95% CI = 2.18 to 31.07) for relatives who ever smoked and were related to a case proband who was diagnosed before age 60 years. CONCLUSION: Routine questioning of patients about a family history of pancreatic cancer, the age of onset of this cancer in their relatives, and the patient's smoking status may identify individuals at high risk of pancreatic cancer. Future research exploring the genetic and environmental interactions associated with the risk of pancreatic cancer is critically important.

HIV-related sexual behaviors of college students.

A follow-up study explored the prevalence of behavioral risk factors for HIV infection in a population of college students. Two hundred forty-three single students ranging in age from 17 to 24 years who identified themselves as heterosexual completed questionnaires related to planned and unplanned sexual intercourse and such other factors as alcohol and nonprescription drug use that might increase the risk of HIV infection. Forty-seven percent of the men and 57% of the women stated that they had had sexual intercourse from 1 to 5 times primarily because they were intoxicated, a phenomenon that increased with age until only 19% of those over 21 had never had sex because of intoxication. Seventeen percent of the sexually active men and 21% of the women said that they had used condoms. Nineteen percent of the men and 33% of the women acknowledged consenting to sexual intercourse because they felt awkward in refusing. The dangerous interaction between alcohol use and high-risk sexual activities suggested that college HIV prevention efforts should make the connection between the two risk factors explicit.

Clinical experience with ciprofloxacin: analysis of a multicenter study.

In a multicenter study of 36 patients treated with ciprofloxacin (mean daily dosage, 986 mg per day; mean duration of treatment, 10.8 days) for a variety of infections, 32 were microbiologically proven. Of these, bacteriologic cure and/or improvement resulted in 100% of cases. For all 36 infections clinical cure and/or improvement resulted in 97.1% of cases. A total of 13 infections were classified as chronic. Overall there were six adverse reactions reported in 4/36 (11.1%) patients. Five were considered related definitely to ciprofloxacin therapy, one was not. Therapy with ciprofloxacin was discontinued in two patients (5.5%). Two patients elected to continue ciprofloxacin therapy despite mild side effects.

The perception of an out-group after provocation by one of its members.

How provocation by a single out-group member exacerbates perceptions of out-group dissimilarity was examined. Male American college students provoked by a Latvian college student not only perceived him as dissimilar from their own group of American college students but also perceived other Latvians (but not Senegalans, an irrelevant out-group) as dissimilar from American college students. Drawing negative inferences about the Latvian provocateur was correlated with perceiving other Latvians as dissimilar.

Volition, performance of a boring task and time estimation.

Subjective intervals were obtained from 40 subjects (20 males, 20 females) who were assigned to a group with or without volition in which choice regarding task involvement was varied. Orthogonal to volition, half the subjects engaged in a boring task, half in an interesting task. Subjects assigned to the group with no volition displayed typical temporal behavior (an interesting task was judged as significantly shorter), while subjects in the group with volition showed no difference in protensity as a function of task quality, yielding the predicted interaction.