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This article examines two pairs of North Atlantic Treaty Organization (NATO) exercises--Teamwork/Bonded Item 76 and Northern Wedding/Bold Guard 78--that had a significant impact on the United States Marine Corps of the late Cold War. These exercises reversed the service's previous ineptitude, repairing its reputation in NATO and helping to quiet U.S. critics of the corps. More importantly, they spurred innovation and boosted deterrence, inspiring enduring changes in service training, equipment, and doctrine while also increasing Soviet perceptions of the conventional threat posed to their flanks. This article adds both to the study of peacetime military change and the historiography of the late Cold War. [ABSTRACT FROM AUTHOR]

Musculoskeletal injuries (MSK-I) are a well-documented problem in military populations and a leading contributor to disability across military services. However, only a portion of Service members who sustain an MSK-I report it to medical providers. Although several studies have identified barriers to seeking medical care in military populations, less is known about what motivates Service members to seek care for MSK-I. To describe determinants of medical care-seeking behavior for MSK-I and/or musculoskeletal pain (MSK-P) in recently enlisted US Marines during military training. Qualitative study. School of Infantry-West (SOI-W), Marine Corps Base Camp Pendleton, California. A total of 1097 US Marines entering Infantry Training Battalion or Marine Combat Training at SOI-W. Participants completed written surveys at entry to (baseline) and graduation from SOI-W. Closed-ended question responses were used to calculate MSK-I/MSK-P and care-seeking frequencies. Open-ended responses describing determinants of care-seeking behavior were analyzed using inductive thematic analysis. Ten percent of participants self-reported sustaining MSK-I during basic training, whereas 14% self-reported sustaining an MSK-I in SOI-W training. A greater proportion reported seeking medical care for their MSK-I/MSK-P during basic training than during SOI-W training. The thematic analysis resulted in 3 main themes that describe drivers and barriers for seeking medical care: (1) self-perceived need for medical care, (2) prioritizing military training, and (3) training-specific influences. Understanding determinants of care-seeking behavior is valuable when designing intervention strategies to promote early MSK-I treatment. Our findings add to previous research to elucidate reasons underlying the decisions about care-seeking for MSK-I/MSK-P. Interventions, including educational strategies and direct approaches like embedding medical providers within units, to minimize barriers to seeking medical care in the military may reduce the burden of MSK-I/MSK-P on Service members throughout their military careers. [ABSTRACT FROM AUTHOR]

Background: Arduous military training frequently consists of prolonged physical activity, sleep disturbance, and stress that increases musculoskeletal injury risk and performance decrements. Inflammatory and oxidative stress responses have been reported in response to arduous training, but with inconsistencies across markers and with underrepresentation of women. The purpose of the current report was to measure circulating inflammation and oxidative stress responses to military training and to correlate biomarkers with subjective measures of stress and sleep quality as well as military fitness test performance. Methods: Candidates undergoing the 10-wk Marine Corps Officer Candidate School (OCS; 101 men, 62 women) were monitored, with demographic and questionnaire data collected, and blood drawn before and after OCS. Blood was analyzed for six markers of inflammation and three markers of oxidative stress. Associations between biomarkers and questionnaire and fitness test performance were tested. Results: All measured inflammatory markers as well as plasma antioxidant capacity were elevated following OCS. The inflammatory increase was higher in women for several markers. Sleep disturbance and stress perception were associated with interleukin (IL)-6, IL-10, and C-reactive protein concentrations, suggesting that low sleep disturbance and stress perception were associated with low inflammatory load. In addition, those with the highest inflammation at each time point performed worse on fitness tests than those with low inflammation. Conclusions: Following arduous military training, the circulating environment in a significant portion of officer candidates resembled chronic low-grade inflammation. This circulating inflammatory environment appeared worse with poor sleep, high stress perception, and poor fitness test performance, with utility observed for C-reactive protein, IL-6, and IL-10 as biomarkers of these responses. Because inflammation may contribute to musculoskeletal injury and performance decrements, minimizing chronic inflammation during military training should be explored. [ABSTRACT FROM AUTHOR]

Purpose: Recent Department of Defense policy changes for hearing conservation programs mandate hearing protector fit testing (HPFT) for many noiseexposed populations. However, the implementation of this requirement across various clinical scenarios is not yet defined. This Quality Improvement (QI) study evaluated the efficacy of current educational procedures at a U.S. Marine Corps (USMC) accession point by performing HPFT before and after small-group training. Method: The QI study employed a pre- and postgroup design to evaluate the effectiveness of training. HPFT was conducted on 122 USMC recruits before and after small-group instruction during hearing conservation in-processing. A field microphone-in-real-ear system was used to calculate the personal attenuation rating for each participant. Additionally, 48 recruits returned for a 1-month follow-up to repeat the fit test procedure. Results: Small-group HPD training resulted in a mean personal attenuation rating improvement of 14.6 dB among a cohort of USMC recruits. One month after training, a decrease in PAR was observed, yet outcomes remained notably higher than baseline, indicating sustained training effectiveness. Conclusions: This study highlights the utility of small-group HPD training in improving immediate fit-test outcomes. Implementing these procedures at large-scale in-processing events, such as military accession points, should be considered a viable option. Future research should focus on long-term maintenance strategies, as sustaining these outcomes over time remains a challenge. [ABSTRACT FROM AUTHOR]

Introduction: Overuse musculoskeletal injuries (MSKI) remain a significant medical challenge in military personnel undergoing military training courses; further understanding of the biological process leading to overuse MSKI development and biological signatures for injury risk are warranted. The purpose of this study was to determine the association between overuse MSKI occurrence and physiological characteristics of allostatic load characterized as maladaptive biological responses to chronic stress measured by wearable devices in US Marine Corps officer candidates during a 10-wk training course. Methods: Devices recorded energy expenditure (EE), daytime heart rate (HR), sleeping HR, and sleep architecture (time and percentage of deep, light, rapid eye movement sleep, awake time, total sleep). Flux was calculated as the raw or absolute difference in the average value for that day or night and the day or night beforehand. Linear mixed-effect model analysis accounting for cardiorespiratory fitness assessed the association between overuse MSKI occurrence and device metrics (α = 0.05). Results: Sixty-nine participants (23 females) were included. Twenty-one participants (eight females) sustained overuse MSKI. Overuse MSKI occurrence in male participants was positively associated with daytime HR (β = 5.316, P = 0.008), sleeping HR (β = 2.708, P = 0.032), relative EE (β = 8.968, P = 0.001), absolute flux in relative EE (β = 2.994, P = 0.002), absolute EE (β = 626.830, P = 0.001), and absolute flux in absolute EE (β = 204.062, P = 0.004). Overuse MSKI occurrence in female participants was positively associated with relative EE (β = 5.955, P = 0.026), deep sleep time (β = 0.664, P < 0.001), and percent deep sleep (β = 12.564, P < 0.001) and negatively associated with absolute flux in sleeping HR (β = -0.660, P = 0.009). Conclusions: Overuse MSKI occurrences were associated with physiological characteristics of allostatic load, including chronically elevated HR and EE and greater time in restorative sleep stages, which may serve as biological signatures for overuse MSKI risk. [ABSTRACT FROM AUTHOR]

BACKGROUND: Drinking water at US Marine Corps Base Camp Lejeune, North Carolina, was contaminated with trichloroethylene and other industrial solvents from 1953 to 1985 METHODS: A cohort cancer incidence study was conducted of Marines/Navy personnel who began service and were stationed at Camp Lejeune (푁 = 154,821) or Camp Pendleton, California (푁 = 163,484) between 1975 and 1985 and civilian workers employed at Camp Lejeune (푁 = 6,494) or Camp Pendleton (푁 = 5,797) between October 1972 and December 1985. Camp Pendleton’s drinking water was not contaminated with industrial solvents. Individual-level information on primary invasive cancers and in situ bladder cancer diagnosed between 1996 and 2017 was obtained from 54 US cancer registries. Proportional hazards regression was used to calculate adjusted hazard ratios (aHRs) comparing cancer incidence between the Camp Lejeune and Camp Pendleton cohorts, adjusted for sex, race, education, and rank (or blue-collar work), with age as the time variable. Precision of aHRs was evaluated using the 95% confidence interval (CI) ratio (CIR). RESULTS: Cancers among Camp Lejeune Marines/Navy personnel and civilian workers totaled 12,083 and 1,563, respectively. Cancers among Camp Pendleton Marines/Navy personnel and civilian workers totaled 12,144 and 1,416, respectively. Compared with Camp Pendleton, Camp Lejeune Marines/Navy personnel had aHRs ≥1:20 with CIRs ≤3 for all myeloid cancers (HR = 1:24; 95% CI: 1.03, 1.49), acute myeloid leukemia (HR = 1:38; 95% CI: 1.03, 1.85), myelodysplastic and myeloproliferative syndromes (HR = 1:68; 95% CI: 1.07, 2.62), polycythemia vera (HR = 1:41; 95% CI: 0.94, 2.11), and cancers of the esophagus (HR = 1:27; 95% CI: 1.03, 1.56), larynx (HR = 1:21; 95% CI: 0.98, 1.50), soft tissue (HR = 1:21; 95% CI: 0.92, 1.59), and thyroid (HR = 1:22; 95% CI: 1.03, 1.45). Lymphoma subtypes mantle cell and marginal zone B-cell and lung cancer subtypes adenocarcinoma and non-small cell lung cancer also had aHRs ≥1:20 with CIRs ≤3. Compared with Camp Pendleton, Camp Lejeune civilian workers had aHRs ≥1:20 with CIRs ≤3 for all myeloid cancers (HR = 1:40; 95% CI: 0.83, 2.36), squamous cell lung cancer (HR = 1:63; 95% CI: 1.10, 2.41), and female breast (HR = 1:21; 95% CI: 0.97, 1.52) and ductal cancer (HR = 1:32; 95% CI: 1.02, 1.71). CONCLUSION: Increased risks of several cancers were observed among Marines/Navy personnel and civilian workers exposed to contaminated drinking water at Camp Lejeune compared with Camp Pendleton. [ABSTRACT FROM AUTHOR]

The present study aimed to explore the effect of ultrasound-stimulated microbubble cavitation (USMC) on drug concentration and therapeutic efficacy of oral gefitinib in treating subcutaneously transplanted SKOV3 ovarian cancer tumors in nude mice. The present study employed the VINNO70 ultrasonic diagnostic and treatment integrated machine for USMC therapy. Firstly, the mechanical index was set at 0.25, and the therapeutic efficacy of USMC treatment was assessed at intervals of 5, 10 and 20 min. Briefly, 72 nude mice were randomized into the following four groups (n=18/group): Control group, USMC5 min group, USMC10 min group and USMC20 min group, and the therapeutic response to USMC treatment was evaluated by comparing pre-and post-intervention effects. Additionally, the combined therapeutic efficacy of USMC and gefitinib was investigated by randomly dividing 96 tumor-bearing mice into the following four groups (n=24/group): Control group, USMC group, gefitinib group and USMC + gefitinib group. Contrast-enhanced ultrasound, hematoxylin and eosin staining, western blotting, immunofluorescence staining, TUNEL staining, ELISA and liquid chromatography-mass spectrometry were performed in the present study. The results showed that USMC combined with gefitinib had the best treatment effect; the tumor inhibition rate was higher than that of gefitinib alone and the overall survival time was prolonged. In addition, the drug concentration in the tumor tissue obtained from the USMC + gefitinib group was revealed to be ~1.4 times higher than that detected in the group treated with gefitinib alone. The experimental results also confirmed that the strongest tumor inhibition rate and longest overall survival time was observed in the USMC + gefitinib group, followed by the gefitinib group and USMC group. STAT3 is an important signaling transducer and transcription factor, which, when phosphorylated, can lead to abnormal cell proliferation and malignant transformation. In addition, the upregulation of phosphorylated (p)-STAT3 is consider a reason for the poor efficacy of gefitinib in treating ovarian cancer. The present study revealed that ultrasound microbubble therapy could overcome this side effect. In conclusion, USMC improved the effects of oral gefitinib on subcutaneously transplanted SKOV3 ovarian cancer tumors in nude mice and increased drug penetration. In addition, USMC overcame the gefitinib-induced side effect of upregulated STAT3 phosphorylation and reduced the expression levels of p-STAT3 in the tumor. [ABSTRACT FROM AUTHOR]

Summary: This paper targets to minimize the peak common mode voltage (CMV) in ultra sparse matrix converters (USMC) by applying new zero vectors for the space vector modulation technique (SVM). Conventional zero vectors in the SVM raise the peak CMV by 42.23%. An increased magnitude of CMV is associated with the occurrence of leakage current, hence resulting in insulation degradation. So, the reduction of peak CMV is necessary for USMC. The proposed method offers suitable switching arrangements using auxiliary shoot through (AST) switches to minimize the peak‐to‐peak CMV. This proposed method holds the advantages of the conventional method, like a wide range of modulation index and zero current switching at the rectifier side, and also reduces the CMV problem. This paper also provides a comparative analysis of the existing reported methods and the proposed method. The effectiveness of the proposed method is validated through both simulation and experimental results. [ABSTRACT FROM AUTHOR]

Background: Previous studies have found that unintended pregnancy rates are higher among racial minorities and active duty servicewomen (ADSW), correlating with lower rates of effective contraceptive use. The Military Health System (MHS) provides universal health care benefit coverage for all ADSW, including access to all highly effective contraceptive (HEC) methods. This study investigated the association between race and HEC use among ADSW. Materials and Methods: We conducted a cross-sectional study using fiscal year 2016–2019 data from the MHS Data Repository for all ADSW ages 18–45 years. Statistical analyses included descriptive statistics and logistic regression models, adjusted and unadjusted, determining the odds of HEC use, overall and by method. Results: Of the 729,722 ADSW included in the study, 59.7% used at least one HEC during the study period. The highest proportions of users were aged 20–24 years, White, single, Junior Enlisted, and serving in the Army. Lower odds of HEC use were demonstrated in Black (odds ratio [OR] = 0.94, 95% confidence interval [CI] = 0.92–0.95), American Indian/Alaska Native (OR = 0.85, 95% CI = 0.82–0.89), Asian/Pacific Islander (OR = 0.81, 95% CI = 0.80–0.83), and Other (OR = 0.97, 95% CI = 0.94–0.99) ADSW compared with White ADSW. Conclusions: Universal coverage of this optional preventive service did not guarantee its use. The MHS can serve as a model for monitoring racial disparities in HEC use. [ABSTRACT FROM AUTHOR]

Despite having to carry the same occupational load, female soldiers tend to be lighter than male soldiers. The aim of this study was to determine the differences in cardiovascular load between female and male US Marine recruits during progressive load carriage hikes. United States Marine Corps recruits (565 male recruits; 364 female recruits) completed 6 loaded hikes over 6 weeks (1:10 kg, 30 minutes; 2: 10 kg, 45 minutes; 3: 15 kg, 30 minutes, 4: 15 kg, 45 minutes; 5: 20 kg, 30 minutes; 6: 20 kg, 45 minutes) during which cardiovascular response was measured. Average heart rate (HRavg), HR maximum (HRmax), and pace were measured via a wrist-worn physiological monitor. Independent sample t-tests were conducted to compare between sexes, with significance set at 0.008 after adjusting for multiple comparisons. The average female recruit had significantly lower body mass (BM) compared with the average male recruit (p < 0.001) and thus carried a significantly heavier relative load. (10 kg ~17%, 15 kg ~25%, 20 kg ~33%, p < 0.001). There were no significant differences in pace in any hike, and no significant differences were found in HRavg or HRmax when comparing female and male Marines during Hike 1. For female Marines, HRavg was significantly higher compared with male Marines during Hike 2 (+6.5 b⋅min-1, p < 0.001) and Hike 3 (+7.4 b⋅min-1, p < 0.001), and both HRavg and HRmax were significantly higher in Hike 4 (+11.9 b⋅min-1, +8.4 b⋅min-1, p < 0.001), Hike 5 (+7.7 b⋅min-1, +7.9 b⋅min-1, p < 0.001), and Hike 6 (+6.9 b⋅min-1, +7.1 b⋅min-1, p < 0.001), respectively. Female Marines endured greater cardiovascular demand compared with male Marines during load carriage events when carrying loads greater than 15 kg (~25% BM). [ABSTRACT FROM AUTHOR]

Introduction Musculoskeletal injuries (MSIs) occur frequently in military personnel. U.S. Marine Corps (USMC) recruits participate in an intense 13-week training program designed to transform civilians into basically trained Marines, during which they are susceptible to MSIs. Previous injury epidemiology research with USMC recruits was conducted in a non-gender-integrated training. Data for the current study were derived from a larger study, the USMC Gender-Integrated Recruit Training study, that was initiated to provide data-driven recommendations for gender integration during USMC recruit training. The purpose of the current analysis was to describe the unique profile of MSIs during USMC recruit training and compare MSIs between female and male recruits in gender-integrated training. Materials and Methods Medical record–reviewed MSI data were obtained for recruits in three models of USMC recruit training: two models of gender-integrated recruit training at Marine Corps Recruit Depot (MCRD) Parris Island—the older Series Track (ST) model and the newer Integrated Company (IC) model, and a Male-Only (MO) cohort at MCRD San Diego. Incidence, anatomic region and subregion, event at the time of MSI, MSI type and onset, and disposition following MSI were described for each model. Group comparisons were conducted using Fisher's exact tests or independent samples t tests, as appropriate. Results MSI data were available for 584 recruits (ST: 98 female recruits, 95 male recruits; IC: 85 female recruits, 106 male recruits; MO: 200 male recruits). The cumulative incidence of MSIs was significantly higher among female compared to male recruits in the ST (59.2% vs. 29.5%, P  < .001) and in the IC (25.9% vs. 12.3%, P = .023) cohorts. The most frequent anatomic location for MSIs was the lower extremity (female recruits: ST: 76.5% of MSIs, IC: 88.6%; male recruits: ST: 81.1%, IC: 80.0%, MO: 83.8%). The most frequent body part affected was the hip among female recruits (ST: 26.5% of MSIs, IC: 37.1%). The most frequent body part affected by MSIs among the male recruits was the knee in the ST (32.4%) and IC (53.3%) cohorts and the lower leg (27.0%) in the MO cohort. A significantly greater percentage of female compared to male recruits sustained a hip MSI in the ST (23.5% vs. 2.1%, P  < .001) and IC (12.9% vs. 0.0%, P  < .001) cohorts. There was no significant difference in knee MSI incidence between sexes in the ST (P  = .323) or IC (P  = .757) cohorts. A large percentage of MSIs resulted in light duty (female recruits: ST: 69.4% of MSIs, IC: 74.3%; male recruits: ST: 64.9%, IC: 73.3%, MO: 94.6%). Conclusions This was the first study to assess the burden of MSIs concurrently among female and male USMC recruits in gender-integrated training. MSIs, especially those affecting the lower extremity, continue to occur frequently in this population. Female recruits are more susceptible to MSIs during USMC recruit training compared to male recruits and are especially prone to hip MSIs. Future research should focus on identifying modifiable risk factors for MSIs in this population, with a focus on reducing lower-extremity MSIs in all recruits and hip MSIs in female recruits. [ABSTRACT FROM AUTHOR]

Introduction Recruit training is designed to transform civilians into physically fit military service members, who embody their service's core values and possess military discipline and skills. At the time this research began, the U.S. Marine Corps (USMC) remained the only service that segregated recruits by gender at the lowest unit level (e.g. platoon) and employed gender-segregated drill instructor teams. USMC's Marine Corps Recruit Depots (MCRD) must comply with a 2020 Congressional Mandate to not segregate training by gender in Parris Island by 2025 and San Diego by 2028. In turn, USMC requested an independent scientific study to analyze current approaches to gender integration at recruit training to propose alternate models and other policy recommendations that increase gender integration while maintaining current USMC standards. The Marine Corps is currently evaluating alternate models and recommendations to optimize entry-level training. This article outlines considerations for choosing the optimal research study design, research methods, and types of data collected in a study intended to provide policy recommendations on gender-integrated recruit training for the USMC. Materials and Methods Research data were collected during visits to the MCRDs and selected recruit training locations for the Army, Air Force, Navy, and Coast Guard. Data collection on USMC recruits from three cohorts involved social science assessments (focus groups and surveys) and human performance testing (countermovement jumps and isometric mid-thigh pulls, sleep and activity wearables, and cortisol data) at multiple points in the training cycle. Data on recruits from the sister services were limited to social science assessments. Approximately 600 recruits between the two MCRDs and 160 recruits from the sister services participated in the study during a 7-month timeframe in 2021. The research team conducted extensive ethnographic observations of recruit training at all selected research sites and interviewed training cadre, drill instructors, and service leadership responsible for recruit training (∼90 interviews). Additionally, the research team interviewed 20 experts on gender integration or recruit training who possessed alternate viewpoints from the current USMC practice. Results The mixed methods study was designed to assess the current gender integration practices at recruit training across the services to generate alternative models of gender integration for USMC. The research team developed a set of multidisciplinary objectives and research questions serving as the foundation of the research study design and data collection process. The study was designed to collect qualitative, quantitative, and administrative data informed by social science and human performance disciplines. To ensure that all aspects and implications relevant to gender integration were considered, select data were collected across services and with stakeholders at all levels. Conclusions This multidisciplinary research approach provided a comprehensive picture of the current USMC recruit training models. The research team captured multiple perspectives and data points for analysis through an expansive view on gender integration across all services, by interacting with participants at all levels of the institutions in varied ways. The information and data gathered enabled the research team to establish objective, data-driven alternate models, and recommendations for enhancing gender integration at recruit training for the USMC. [ABSTRACT FROM AUTHOR]

Introduction This article uses recent survey data from a study on gender integration at recruit training across the U.S. Armed Forces to examine service, gender, and training differences in recruit's gender attitudes, beliefs, and cohesion metrics. In addition to providing a descriptive understanding of our recruit sample, this article examines factors germane to gender integration at recruit training such as gender attitudes, sexist beliefs, and unit cohesion. Materials and Methods This article uses data from a survey of U.S. Marine Corps (USMC), U.S. Army, U.S. Air Force, U.S. Navy, and U.S. Coast Guard recruits as part of a USMC-commissioned study to develop alternate models and recommendations for increasing gender integration in USMC recruit training. At all sites but the USMC, recruits completed the survey 1 to 2 weeks before graduation. At the Marine Corps Recruit Depots, recruits participated in the survey at the beginning (week 2) and end (week 11) of their 13-week training cycle. A 19-question survey captured sociodemographic information, perspectives and experiences during recruit training, and gender attitudes and beliefs. Analyses were conducted on the sample with complete data on the measures reported, including those USMC recruits observed at both week 2 and week 11 (n  = 629). Descriptive statistics (percentage) were calculated for all categorical outcome variables. Outcome variables (cohesion, gender, and sexism attitudes) were compared between groups using chi-squared tests or Fisher's exact tests, as appropriate. Results Recruits differed significantly across services in perceptions of unit cohesion on 3 of the 4 indicators: Platoon members are cooperative, know they can depend on each other, and really respect each other (P <  .05). These differences appear to be driven by female recruit difference across service. They reported significant differences in gender role attitudes across the services, with USMC recruits being most likely to endorse traditional gender roles compared to other service recruits. Male USMC recruits were significantly more likely than their female peers to agree that men should achieve outside the home and women should take care of the home and family (21.3% versus 6.3%, P <  .05). The only statistical differences in attitudes about equality of treatment and opportunity among recruits were between male and female USMC recruits. All items capturing sexist attitudes elicited statistically significant differences between male USMC recruits and male recruits in other services (P <  .05). There were significant differences in all sexism measures between male and female USMC recruits (P <  .05). There is a significant decline in some sexist attitudes between weeks 2 and 11 of training among male USMC recruits (P <  .05). Nearly one-half to three-fourths of male USMC recruits hold sexist attitudes, even near the end of recruit training. Conclusions The disparate gender and sexism attitudes of male USMC recruits compared with their peers in other services, and their fellow female USMC recruits suggest efforts to increase gender integration at entry-level training are needed, but also may be challenging since male USMC recruits report the highest levels of sexist attitudes among all recruits. [ABSTRACT FROM AUTHOR]

Introduction Injury epidemiology research with military populations typically utilizes data obtained through medical chart review (MCR) or injury self-reports (ISRs). MCR data will not capture musculoskeletal injury (MSKI) data for which medical care was not sought, which is common during military recruit training. Injury self-report is affected by issues with recall, especially for MSKIs perceived as less severe. U.S. Marine Corps (USMC) recruits participate in an intense 13-week recruit training program during which they are susceptible to MSKIs. The purpose of the current analysis was to utilize a novel statistical method, the capture-recapture (CRC) technique, to account for the undercounting inherent in MSKI data sources and estimate the ascertainment-corrected cumulative incidence of MSKIs during USMC recruit training. Materials and Methods Data for the current study were derived from a larger study, the USMC Gender-Integrated Recruit Training Study, which was initiated to provide data-driven recommendations to increase gender integration in USMC recruit training. The estimated cumulative incidence of MSKIs during 13-weeks of USMC recruit training was calculated from the 2 sources of MSKI data (MCR, ISR) and using CRC analysis. Medical charts were reviewed to extract data about MSKIs that occurred during recruit training. Self-reported MSKI data for the same period were obtained from recruits at the end of recruit training. MSKIs were classified according to their anatomical location and type. The Chapman modification of the Lincoln-Peterson estimator was utilized to conduct the CRC analysis. Results Medical chart review and ISR MSKI data were available for 464 USMC recruits (age: 19.1 ± 1.9 years; gender: men 70.0%). The observed 13-week cumulative incidence of MSKI in the sample was 21.8% in the MCR and 28.4% in the ISR, while the CRC incidence was much higher (62.0%). The MCR and ISR ascertainment were 35.1% and 45.9%, respectively, while the overall ascertainment or completeness of MSKI data when 2 sources were used was moderate (65.0%). When stratified by MSKI anatomical location, the overall ascertainment varied by anatomical location of the MSKI. It was highest for lower extremity MSKIs (64.8%), but lower for upper extremity (38.9%) and spine (33.3%) MSKIs. The overall ascertainment also varied by MSKI type; it was highest for sprain (55.1%), followed by strain (54.8%), and the pain/spasm/ache (43.3%). Conclusions This was the first study to utilize the CRC technique to access the ascertainment-corrected incidence of MSKIs among USMC recruits. There was significant undercounting in both sources of the data analyzed, and the extent of undercounting varied by both MSKI anatomical location and type. When 2 sources of data were utilized simultaneously, the percent of CRC-estimated MSKIs observed from 2 sources of data was more complete. There is a need for further application of the CRC technique to MSKI data in military populations to provide a more complete assessment of MSKIs. Identification of modifiable factors that influence completeness of MSKI data obtained during military recruit training is also warranted. [ABSTRACT FROM AUTHOR]

Introduction Elevated rates of musculoskeletal injuries (MSIs) and attrition are documented in military recruit training. By identifying and addressing modifiable risk factors, the rate of successful training completion and military readiness can be enhanced. Despite their impact, the causes of MSIs and attrition among U.S. Marine Corps (USMC) recruits remain underexplored. This study investigates demographic, psychological, and physiological predictors of MSIs and attrition among USMC recruits. Materials and Methods In this prospective cohort study, we evaluated USMC recruits at Marine Corps Recruit Depot, Parris Island and San Diego. Recruits were briefed and invited to volunteer. All recruits who were medically cleared to participate in recruit training were eligible to participate in the study. We gathered baseline data on potential predictors at the start of training, with follow-up data on MSIs and attrition collected post-training. Analyzed predictors encompassed dynamic and static strength measures from countermovement jumps, isometric mid-thigh pulls; and participant surveys. We employed multiple logistic regression to discern risk factors for MSI and attrition. Results Our study comprised 584 USMC recruits (183 female recruits, 19.49 ± 1.88 years, 160.10 ± 7.17 cm, 61.19 ± 8.05 kg; 401 males, 18.94 ± 1.92 years, 172.97 ± 7.26 cm, 73.86 ± 11.04 kg). We observed 193 MSIs in 135 recruits, with 80.31% affecting the lower extremity (LE). Notably, lower relative peak power (odds ratio [OR] 0.91 [0.89, 0.94], P  < .001) and shorter eccentric deceleration duration (OR 0.99 [0.99, 1.00], P  = .005) were significant predictors of MSIs. Specifically, for LE MSIs, similar trends were noted for relative peak power and eccentric deceleration duration, with additional risks associated with lower body mass index (OR 0.93 [0.86, 0.99], P  = .036) and previous LE MSIs (OR 2.25 [1.18, 4.27], P  = .013). Attrition was more likely with a reduced eccentric deceleration impulse (OR 0.98 [0.97, 0.99], P  < .001) and prolonged time to peak force (OR 1.36 [1.17, 1.59], P  < .001) and cigarette use (OR 2.12 [1.01, 4.43], P  = .046). Conclusions MSIs and attrition during USMC recruit training significantly undermine force readiness and escalate costs. Our research has pinpointed several modifiable risk factors, chiefly reduced muscular power and cigarette smoking. We advocate for neuromuscular training programs to bolster strength and power, integrated nutrition and exercise strategies for optimal body composition, and support for smoking cessation to alleviate the incidence of MSIs and curtail attrition. Initiating training with a gradual increase in activity intensity can provide a critical window to correct pre-existing neuromuscular imbalances and weaknesses, particularly those stemming from prior MSIs. Effectively addressing these risk factors is pivotal for diminishing the rates of MSIs and attrition among recruits, thereby enhancing overall military readiness and operational efficiency. [ABSTRACT FROM AUTHOR]

Introduction United States Marine Corps' (USMC) recruit training is a 13-week program designed to maximize physical and mental performance adaptations. The purpose of this study was to evaluate the training demands and characteristics that are associated with performance outcomes during USMC recruit training. Materials and Methods A total of 196 recruits (M = 97 and W = 99) were monitored and tested throughout training. Laboratory-based performance testing occurred at the start of weeks 2 and 11 and consisted of body mass assessments, countermovement vertical jump, and isometric mid-thigh pull. Military-specific performance testing occurred twice within the first 8 weeks of training and included the physical fitness test (PFT) and combat fitness test (CFT) implemented by the USMC. Resilience data were collected at week 2 using the Connor-Davidson Resilience Scale. Workload, sleep, and stress responses were monitored at weeks 2, 7, and 11. Recruits were provided with a wearable tracking device which utilized heart rate and accelerometry-based technology to determine energy expenditure (EE), distances (DIS), and sleep metrics. Data were averaged over a 3-day period. Salivary cortisol testing occurred at the start of each monitoring week. Change scores were calculated for performance tests, and body mass was calculated from data obtained at week 2 to week 11. Area under the curve was calculated for the workload, sleep metrics, and cortisol responses using the trapezoidal method. Pearson product–moment correlations (r) were used to assess the relationships between training demands and performance. An α level of 0.05 was used to establish significance. Results A moderate positive correlation was found between changes in body mass and peak power (P  < .001; r  = 0.43). Weak positive correlations were found between changes in body mass and peak force (P  = .002; r  = 0.28), as well as body mass and resilience (P  = .03; r  = 0.19). A moderate negative correlation was observed between changes in body mass and PFT (P  < .001; r  = −0.49). A weak negative correlation was found between changes in body mass and EE (P  = .003; r  = −0.24). A weak negative correlation was found between changes in peak power and EE (P  = .001; r  = −0.29). A weak positive correlation was found between changes in peak power and changes in CFT (P  = .05; r  = 0.19) A weak negative correlation was found between changes in sleep continuity and CFT (P  = .02; r  = −0.20). A weak negative correlation was found between cortisol and changes in PFT (P  = .05; r  = −0.20). A weak negative correlation was found between cortisol and both EE (P  = .001; r  = −0.27) and DIS (P  = .045; r  = −0.16). A weak negative correlation was found between EE and sleep continuity (P  < .001; r  = −0.34). Weak negative correlations were found between sleep duration and both DIS (P  = .01; r  = −0.18) and steps (P  = .003; r  = −0.21). Conclusions Increases in body mass throughout training were positively associated with strength and power changes, but negatively related to PFT scores. Changes in peak power related to improvements in CFT scores; however, higher workloads (i.e. EE) were negatively associated with peak power. The identification of the USMC physical and physiological training demands that are associated with performance outcomes may be a valuable resource to guide conditioning efforts to boost military readiness. [ABSTRACT FROM AUTHOR]

Introduction Drill instructors (DIs) are responsible for executing their Services' recruit training programs and for training recruits. DIs assume a variety of roles, including teaching and developing practical skills and knowledge, mentoring, modeling appropriate behavior and attitudes, motivating recruits for success during and after recruit training, applying and instilling discipline, and ensuring the safety and welfare of recruits. This article examines two major research questions at the intersection of gender, gender-integrated training, and the DI role: (1) What differences exist in how DIs experience their role by gender? and (2) how does gender-integrated recruit training affect DIs' approach to training? Materials and Methods This article draws from 87 semistructured interviews conducted with Service leaders, training cadre, and DIs in service of a broader Marine Corps interdisciplinary study on gender integration at recruit training. Interviews were conducted virtually and in-person with Marine Corps, Army, Navy, Air Force, and Coast Guard personnel from June to November 2021. Each interview was coded with initial and secondary codes developed through a flexible coding approach. Data were analyzed across and within relevant categories such as gender and Service to identify themes and patterns. Results Although the DI role was universally described as demanding and difficult, unique challenges for women consistently emerged from the data. The top reported challenges faced by female DIs were personnel shortages, work and family conflict, culture-driven sexism in the training environment from male peers and recruits, and pressure to excel above and beyond their male peers. In recruit training, DIs are responsible for executing gender-integrated practices. Service leaders, training cadre, and DIs described how gender integration practices affect their approach to the role and implementation of training, including addressing and dismantling sexism, shutting down recruit romantic relationships, training all recruits in an equal manner, knowing gender-specific grooming standards, increasing communication among DIs, and working with mixed-gender DI teams. Conclusions Female DIs face additional challenges in and outside the role compared with their male peers, and some of these challenges are preventable. Staffing and personnel issues plague the female DI population and are a persistent and pervasive challenge to gender integration efforts. Women are a necessary and highly desirable population to fill the DI role, particularly as Services aim to expose recruits to leaders of both genders during their critical first training experience. DIs play an important role in ensuring the successful completion of recruit training, ultimately helping to build the future leaders of the military. The success of gender integration efforts depends on DIs' intentional approach to the process. Future research can build on this work by expanding the scope to other military training environments (beyond recruit training) and examining how DIs' own sociodemographic positions (e.g. gender, race, ethnicity, and sexual orientation) inform their perspective on and approach to equity in the training environment. [ABSTRACT FROM AUTHOR]

Introduction The U.S. Marine Corps (USMC) recruit training is a 13-week preparatory period for military service men and women. Differences in absolute performance capabilities between sexes may impact physical and physiological responses to the demands of recruit training. The purpose of this study was to monitor U.S. Marine Corps recruits throughout recruit training to comparatively assess workload, sleep, stress, and performance responses in men and women. Materials and Methods A total of 281 recruits (men = 182 and women = 99; age = 19 ± 2 years) were monitored and tested. Workload, sleep, and stress assessments occurred at week 2, week 7/8, and week 11 of training. Workload (energy expenditure per kg body mass [EEREL], distance [DIS], steps) and sleep (continuity and duration) were tracked over 72-hour periods using wearable accelerometry and heart rate technology. Stress responses were determined through salivary cortisol analyses. Performance testing, consisting of countermovement vertical jump (CMJ) and isometric mid-thigh pull (IMTP) performance relative to body mass, occurred at weeks 2 and 11. Linear mixed models were used to test for sex, time, and sex-by-time interactions (α < .05). Results On average, recruits covered 13.0 ± 2.7 km/day, expended 3,762 ± 765 calories/day, and slept 6.2 ± 1.1 hours/night. Sex-by-time interactions were found for DIS, steps, sleep duration, cortisol, and CMJREL performance (P  < .05). Planned contrasts revealed that men covered more DIS than women at week 7/8 (P  < .001). Women experienced greater step counts compared to men at week 11 (P  = .004). Women experienced no significant change in sleep duration (P  > .05), whereas men increased sleep duration from week 2 to week 7/8 (P  = .03). Women experienced greater sleep duration at week 2 (P  = .03) and week 11 (P  = .02) compared to men. Women exhibited higher cortisol levels than men at week 2 (P  < .001) and week 11 (P  < .001). Women experienced declines in cortisol at week 7 compared to week 2 (P  < .001). Men experienced no changes in cortisol response at any timepoint (P  > .05). Both sexes experienced declines in CMJREL from week 2 to week 11 (P  > .001). Sex main effects were observed for EEREL, DIS, CMJREL, and IMTPREL (P  < .05) with men experiencing greater overall workloads and producing greater strength and power metrics. Sex main effects were also found for sleep continuity and cortisol (P  < .05), for which men experienced lower values compared to women. Time main effects were observed for EEREL, DIS, steps, cortisol, CMJREL, and IMTPREL (P  < .05). Conclusions This study not only highlights the known sex differences between men and women but also sheds light on the different physical and physiological responses of each sex to military training. Interestingly, the greatest physical demands incurred earlier in the training cycle. Despite declining workloads, the stress response was maintained throughout the training, which may have implications for adaptation and performance. In addition, average sleep duration fell notably below recommendations for optimizing health and recovery. Effectively monitoring the demands and performance outcomes during recruit training is essential for determining individual fitness capabilities, as well as establishing the effectiveness of a training program. Individual performance assessments and adequately periodized workloads may help to optimize recruit training for both men and women. [ABSTRACT FROM AUTHOR]

Introduction Recruit training is the initial entry for enlisted personnel in the military. The Services execute gender-integrated recruit training differently. The U.S. Marine Corps (USMC) maintains same-gender platoons led by same-gender drill instructors in integrated companies; further integration occurs at select training events. The other Services train recruits in gender-integrated units with mixed-gender drill instructor teams. We examine recruits' experiences and perceptions of gender integration at recruit training, their desired level of integration, and preferences for increasing gender integration, comparing by Service and gender. Materials and Methods Recruit perspectives and experiences were captured in a 19-question survey (n = 632) and 90-min focus groups (n  = 260) near graduation from recruit training. Data were collected from June to November 2021. Because of the Coronavirus disease (COVID-19) pandemic restrictions, the Navy and Air Force were not conducting gender-integrated recruit training during data collection. Outcome variables were compared cross-Service by gender and within Service by gender using chi-squared tests or Fisher's exact tests, as appropriate; focus group data were analyzed using initial and secondary coding schemes. Three USMC training models, varied by level of integration, were also analyzed (Male-Only, Series Track, and Integrated Company). Results Significant gender differences across and within Service emerged in recruits' experience being trained by an opposite-gender instructor. Male recruits had significant differences by Service (P  < .001), and USMC female recruits reported being trained by male instructors more than their male peers by female instructors (Series Track P  = .002; Integrated Company P  < .001). In the focus groups, recruits described common differences with how men and women embodied being a drill instructor. Significant gender differences across (both male and female P  < .001) and within Service were reported for closeness of training with opposite-gender peers (Air Force P  = .028; U.S. Marine Corps (USMC) Integrated Company P  = .010; Army P  = .048), an expected finding given varied integration during data collection. Male and female recruits had significant differences by Service in their preference for integration at the lowest unit level (both male and female P  < .001), with those who experienced integrated training showing higher levels of endorsement. In the focus groups, recruits articulated benefits and challenges of gender-integrated recruit training. Significant gender differences across Service emerged in preferences for more integration in specific training activities. Within Service, female USMC Integrated Company recruits wanted more integration in tactical/field, physical fitness, and classroom training than their male peers (P  < .001 for all). In the focus groups, USMC recruits of both genders desired more integrated training events, particularly those involving combat and tactical skill development. Conclusions This study provided an opportunity to examine recruit perspectives on gender-integrated training. Services valuing opposite-gender instructor exposure in recruit training must ensure that male recruits are being taught and led by female instructors given disproportionate demographics. Recruits who experienced integrated training were more supportive of integration, indicating that this experience may increase their support for gender-integrated training units and environments. Today's recruits understand that they are entering gender-integrated working environments, and our results indicate that they expect recruit training to mirror that reality. [ABSTRACT FROM AUTHOR]

Introduction This article describes alternate models and policy recommendations created by an interdisciplinary team of researchers to increase gender integration at U.S. Marine Corps (USMC) recruit training. The USMC requested a study to analyze current approaches to gender integration at recruit training and provide alternate models that maximize integration, while continuing to train marines to established standards. USMC remains the only service that segregates recruits by gender at the lowest unit level (e.g. platoon) in recruit training and maintains gender-segregated drill instructor teams (i.e. same-gender teams train platoons of same-gender recruits). Materials and Methods A mixed-method, interdisciplinary approach was used to capture multiple perspectives and informed recommendations and alternate models for gender integration. The team studied select USMC, army, navy, air force, and coast guard recruit training locations, between June and November 2021. At each site, the team collected qualitative, quantitative, and administrative data as well as physical performance metrics and human performance outcomes. Study participants included recruits, drill instructors, training cadre, service leaders, and subject matter experts on gender integration in military services. Each alternate model was designed to maximize the feasibility of implementation within current USMC training conditions. Results The research team developed three alternate models and several policy recommendations. Alternate model 1 proposed a methodology for mixed-gender drill instructor teams within the Integrated Company model, USMC's current integrated training model. Alternate model 2 proposed an Integrated Company Plus model which increases the number and types of gender-integrated training events at or below the platoon level within the Integrated Company model. Alternate model 3 outlined an integrated platoon model where recruits fall out into integrated training platoons after their morning routine, with two options of varying integration based on USMC priorities for integration. The team also proposed a set of policy recommendations independent of the three alternate models to support current and future gender integration efforts at the Marine Corps Recruit Depots. Conclusions Gender-integrated military training has been shown to positively alter perceptions and evaluations of women in military settings over detrimental aspects developed by gender-segregated training. The study team recommended USMC train recruits in the Integrated Company model with mixed-gender drill instructor teams (alternate model 1) and integrate more training events following the priority tiers outlined in the Integrated Company plus model (alternate model 2). The combined execution of these two alternate models would provide USMC recruits increased exposure to direct, sustained training from opposite-gender drill instructors and deliver intentional training opportunities for male and female recruits to work together and interact in meaningful ways. The integrated platoon model (alternate model 3) would offer USMC recruits the most direct exposure to training and working with members of the opposite gender, but it requires substantial changes to current logistics, accountability, and training procedures. [ABSTRACT FROM AUTHOR]

Introduction Several challenges face the U.S. Marine Corps (USMC) and other services in their efforts to design recruit training to augment warfighter mobility and resilience in both male and female recruits as part of an integrated model. Strength and power underpin many of the physical competencies required to meet the occupational demands one might face in military. As the military considers adopting force plate technology to assess indices of strength and power, an opportunity presents itself for the use of machine learning on large datasets to deduce the relevance of variables related to performance and injury risk. The primary aim of this study was to determine whether cluster analysis on baseline strength and power data derived from countermovement jump (CMJ) and isometric mid-thigh pull (IMTP) adequately partitions men and women entering recruit training into distinct performance clusters. The secondary aim of this study is then to assess the between-cluster frequencies of musculoskeletal injury (MSKI). Materials and Methods Five hundred and sixty-five males (n  = 386) and females (n  = 179) at the Marine Corps Recruit Depots located at Parris Island and San Diego were enrolled in the study. Recruits performed CMJ and IMTP tests at the onset of training. Injury data were collected via medical chart review. Combat fitness test (CFT) and physical fitness test (PFT) results were provided to the study team by the USMC. A k -means cluster analysis was performed on CMJ relative peak power, IMTP relative peak force, and dynamic strength index. Independent sample t -tests and Cohen's d effect sizes assessed between-cluster differences in CFT and PFT performance. Differences in cumulative incidence of lower extremity %MSKIs were analyzed using Fisher's exact test. Relative risk and 95% confidence intervals (CIs) were also calculated. Results The overall effects of cluster designation on CMJ and IMTP outcomes ranged from moderate (relative peak power: d  = −0.68, 95% CI, −0.85 to −0.51) to large (relative peak force: d  = −1.69, 95% CI, −1.88 to −1.49; dynamic strength index: d  = 1.20, 95% CI, 1.02-1.38), indicating acceptable k -means cluster partitioning. Independent sample t -tests revealed that both men and women in cluster 2 (C2) significantly outperformed those in cluster 1 (C1) in all events of the CFT and PFT (P  < .05). The overall and within-gender effect of cluster designation on both CFT and PFT performance ranged from small (d  > 0.2) to moderate (d  > 0.5). Men in C2, the high-performing cluster, demonstrated a significantly lower incidence of ankle MSKI (P  = .04, RR = 0.2, 95% CI, 0.1-1.0). No other between-cluster differences in MSKI were statistically significant. Conclusions Our results indicate that strength and power metrics derived from force plate tests effectively partition USMC male and female recruits into distinct performance clusters with relevance to tactical and physical fitness using k -means clustering. These data support the potential for expanded use of force plates in assessing readiness in a cohort of men and women entering USMC recruit training. The ability to pre-emptively identify high and low performers in the CFT and PFT can aid in leadership developing frameworks for tailoring training to enhance combat and physical fitness with benchmark values of strength and power. [ABSTRACT FROM AUTHOR]

Background: Drinking water at U.S. Marine Corps Base (MCB) Camp Lejeune, North Carolina was contaminated with trichloroethylene and other industrial solvents from 1953 to 1985. Methods: A cohort mortality study was conducted of Marines/Navy personnel who, between 1975 and 1985, began service and were stationed at Camp Lejeune (N = 159,128) or MCB Camp Pendleton, California (N = 168,406), and civilian workers employed at Camp Lejeune (N = 7,332) or Camp Pendleton (N = 6,677) between October 1972 and December 1985. Camp Pendleton's drinking water was not contaminated with industrial solvents. Mortality follow-up was between 1979 and 2018. Proportional hazards regression was used to calculate adjusted hazard ratios (aHRs) comparing mortality rates between Camp Lejeune and Camp Pendleton cohorts. The ratio of upper and lower 95% confidence interval (CI) limits, or CIR, was used to evaluate the precision of aHRs. The study focused on underlying causes of death with aHRs ≥ 1.20 and CIRs ≤ 3. Results: Deaths among Camp Lejeune and Camp Pendleton Marines/Navy personnel totaled 19,250 and 21,134, respectively. Deaths among Camp Lejeune and Camp Pendleton civilian workers totaled 3,055 and 3,280, respectively. Compared to Camp Pendleton Marines/Navy personnel, Camp Lejeune had aHRs ≥ 1.20 with CIRs ≤ 3 for cancers of the kidney (aHR = 1.21, 95% CI: 0.95, 1.54), esophagus (aHR = 1.24, 95% CI: 1.00, 1.54) and female breast (aHR = 1.20, 95% CI: 0.73, 1.98). Causes of death with aHRs ≥ 1.20 and CIR > 3, included Parkinson disease, myelodysplastic syndrome and cancers of the testes, cervix and ovary. Compared to Camp Pendleton civilian workers, Camp Lejeune had aHRs ≥ 1.20 with CIRs ≤ 3 for chronic kidney disease (aHR = 1.88, 95% CI: 1.13, 3.11) and Parkinson disease (aHR = 1.21, 95% CI: 0.72, 2.04). Female breast cancer had an aHR of 1.19 (95% CI: 0.76, 1.88), and aHRs ≥ 1.20 with CIRs > 3 were observed for kidney and pharyngeal cancers, melanoma, Hodgkin lymphoma, and chronic myeloid leukemia. Quantitative bias analyses indicated that confounding due to smoking and alcohol consumption would not appreciably impact the findings. Conclusion: Marines/Navy personnel and civilian workers likely exposed to contaminated drinking water at Camp Lejeune had increased hazard ratios for several causes of death compared to Camp Pendleton. [ABSTRACT FROM AUTHOR]

Few US Marines earn perfect 300 scores on both their Physical Fitness Test (PFT) and Combat Fitness Test (CFT). The number 300 invokes the legendary 300 Spartans that fought at the Battle of Thermopylae, which inspired high physical fitness capabilities for elite ground forces ever since. Purpose: Determine distinguishing characteristics of the "300 Marines" (perfect PFT and CFT scores) that may provide insights into the physical and physiological requirements associated with this capability. These tests have been refined over time to reflect physical capabilities associated with Marine Corps basic rifleman performance. Materials and methods: Data were analyzed from US Marines, including 497 women (age, 29 ± 7 years; height 1.63 ± 0.07 m; body mass, 67.4 ± 8.4 kg) and 1,224 men (30 ± 8 years; 1.77 ± 0.07 m; 86.1 ± 11.1 kg). Marines were grouped by whether they earned perfect 300 scores on both the PFT and CFT (300 Marines) or not. We analyzed group differences in individual fitness test events and body composition (dual-energy x-ray absorptiometry). Results: Only 2.5% (n = 43) of this sample earned perfect PFT and CFT scores (n = 21 women; n = 22 men). Compared to sex-matched peers, 300 Marines performed more pull-ups, with faster three-mile run, maneuver-under-fire, and movement-to-contact times (each p < 0.001); 300 Marines of both sexes had lower fat mass, body mass index, and percent body fat (each p < 0.001). The lower percent body fat was explained by greater lean mass (p = 0.041) but similar body mass (p = 0.085) in women, whereas men had similar lean mass (p = 0.618), but lower total body mass (p = 0.025). Conclusion: Marines earning perfect PFT and CFT scores are most distinguished from their peers by their maneuverability, suggesting speed and agility capabilities. While both sexes had considerably lower percent body fat than their peers, 300 Marine women were relatively more muscular while men were lighter. [ABSTRACT FROM AUTHOR]

To explore the effect of ultrasound-stimulated microbubble cavitation (USMC) on enhancing antiangiogenic therapy in clear cell renal cell carcinoma. We explored the effects of USMC with different mechanical indices (MIs) on tumor perfusion, 36 786-O tumor-bearing nude mice were randomly assigned into four groups: (i) control group, (ii) USMC 0.25 group (MI = 0.25), (iii) USMC 1.4 group (MI = 1.4) (iv) US 1.4 group (MI = 1.4). Tumor perfusion was assessed by contrast-enhanced ultrasound (CEUS) before the USMC treatment and 30 min, 4h and 6h after the USMC treatment, respectively. Then we evaluated vascular normalization(VN) induced by low-MI (0.25) USMC treatment, 12 tumor-bearing nude mice were randomly divided into two groups: (i) control group (ii) USMC 0.25 group. USMC treatment was performed, and tumor microvascular imaging and blood perfusion were analyzed by MicroFlow imaging (MFI) and CEUS 30 min after each treatment. In combination therapy, a total of 144 tumor-bearing nude mice were randomly assigned to six groups (n = 24): (i) control group, (ii) USMC 1.4 group, (iii) USMC 0.25 group, (iv) bevacizumab(BEV) group, (v) USMC 1.4 +BEV group, (vi) USMC 0.25 +BEV group. BEV was injected on the 6th, 10th, 14th, and 18th d after the tumors were inoculated, while USMC treatment was performed 24 h before and after every BEV administration. We examined the effects of the combination therapy through a series of experiments. Tumor blood perfusion enhanced by USMC with low MI (0.25)could last for more than 6h, inducing tumor VN and promoting drug delivery. Compared with other groups, USMC 0.25 +BEV combination therapy had the strongest inhibition on tumor growth, led to the longest survival time of the mice. The optimized USMC is a promising therapeutic approach that can be combined with antiangiogenic therapy to combat tumor progression. [ABSTRACT FROM AUTHOR]

One wintry morning in February 1970, Lillian Boyd, a single mother juggling several housecleaning jobs to make a living for her family in Evansville, Indiana, heard a persistent knocking at [...]

After Iraq occupied Kuwait on August 2, 1990, Saddam Hussein exclaimed it as his country's 19th province. The United States and their allies responded quickly and in force, by, among [...]